U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PubAg

Main content area

You searched for: Publication Year 2008 Remove constraint Publication Year: 2008 Subject canopy Remove constraint Subject: canopy
Start Over

Search

624  Search Results

« Previous | 1 - 100 of 624 |
Number of results to display per page

Search Results

1. Abiotic factors influencing abundance and microhabitat use of stream salamanders in southern Appalachian forests

Author:
Crawford, John A.; Semlitsch, Raymond D.
Source:
Forest ecology and management 2008 v.255 no.5-6 pp. 1841-1847
ISSN:
0378-1127
Subject:
salamanders and newts; Caudata; microhabitats; habitat preferences; soil water; canopy; soil temperature; environmental factors; streams; riparian forests; statistical models; regression analysis; habitat conservation; plant litter; Appalachian region; North Carolina
Abstract:
... In order to evaluate the effects of habitat loss and degradation on amphibian populations it is necessary to determine species-specific habitat use and how this influences abundance. While a number of studies have examined the influence of competition and predation in stream salamander assemblages in the southern Appalachian Mountains, there remains a relative lack of knowledge on the microhabitat ...
DOI:
10.1016/j.foreco.2007.12.005

2. Acclimation of photosynthesis and growth of banana (musa sp.) to natural shade in the humid tropics

Author:
Senevirathna, A.M.W.K.; Stirling, C.M.; Rodrigo, V.H.L.
Source:
Experimental agriculture 2008 v.44 no.3 pp. 301-312
ISSN:
0014-4797
Subject:
tropics; Musa; bananas; shade tolerance; light intensity; acclimation; plant growth; photosynthesis; chlorophyll; leaf area; gas exchange; carbon dioxide; net assimilation rate; dry matter partitioning; intercropping; Hevea brasiliensis; canopy; plantations; Sri Lanka
Abstract:
... Growth and photosynthetic performance of banana (Musa sp.) grown in three levels of natural shade (33, 55 and 77% reduction in incoming radiation) were compared to an unshaded control treatment. Net CO2 assimilation rates generally decreased with increasing shade. Chlorophyll fluorescence revealed short-term dynamic photoinhibition under high light conditions but no evidence of sustained photoinhi ...
DOI:
10.1017/S0014479708006364

3. Actual and potential transpiration and carbon assimilation in an irrigated poplar plantation

Author:
Kim, H.S.; Oren, R.; Hinckley, T.M.
Source:
Tree physiology 2008 v.28 no.4 pp. 559-577
ISSN:
0829-318X
Subject:
primary productivity; gas exchange; Populus deltoides; leaf area index; sap flow; carbon; carbon dioxide; hybrids; stomatal conductance; nutrient uptake; Populus trichocarpa; mathematical models; forest trees; photorespiration; equations; irrigated conditions; leaf water potential; canopy; water use efficiency; forest plantations; light; Northwestern United States
Abstract:
... We examined the tradeoffs between stand-level water use and carbon uptake that result when biomass production of trees in plantations is maximized by removing nutrient and water limitations. A Populus trichocarpa Torr. x P. deltoides Bartr. & Marsh. plantation was irrigated and received frequent additions of nutrients to optimize biomass production. Sap flux density was measured continuously over ...
DOI:
10.1093/treephys/28.4.559
PubMed:
18244943

4. Adaptation and Validation of a Dynamic Plant Surface Microclimate Model (PSCLIMATE) for Greenhouse Tomatoes

Author:
Hao, X.; Zhang, Y.; Shipp, L.; Borhan, M.S.
Source:
Transactions of the ASABE 2008 v.51 no.5 pp. 1715-1725
Subject:
Solanum lycopersicum var. lycopersicum; tomatoes; greenhouse production; microclimate; climate models; model validation; canopy; leaves; heating systems; relative humidity; air temperature; solar radiation; air flow
Abstract:
... The microclimate within a canopy and at the plant surface has a significant influence on the physiological processes of plants and the epidemiology of pathogens. However, it is usually not measured in routine greenhouse climate monitoring and control. We have developed a plant surface climate model for greenhouse cucumbers (PSCLIMATE-CUCUMBER) to predict the vertical microclimate profile within cr ...

5. Adjusting count period strategies to improve the accuracy of forest bird abundance estimates from point transect distance sampling surveys

Author:
LEE, DAVID C.; MARSDEN, STUART J.
Source:
Ibis 2008 v.150 no.2 pp. 315-325
ISSN:
0019-1019
Subject:
birds; canopy; forest surveys; frugivores; insectivores; nectar feeding; omnivores; probability; tropical forests; understory
Abstract:
... Although point transect distance sampling methods have become widely used in surveys of forest birds, there has been no attempt to tailor field methods to maximize the accuracy of abundance estimates by minimizing the effects of violations of the method's critical assumptions, which are: (1) birds at distance 0 m are detected with certainty, (2) birds are detected at their initial location and (3) ...
DOI:
10.1111/j.1474-919X.2007.00790.x

6. Adult butterfly communities in coffee plantations around a protected area in the Western Ghats, India

Author:
Dolia, J.; Devy, M.S.; Aravind, N.A.; Kumar, A.
Source:
Animal conservation 2008 v.11 no.1 pp. 26-34
ISSN:
1367-9430
Subject:
Grevillea robusta; adults; adverse effects; agroforestry; bait traps; butterflies; canopy; fauna; forests; habitats; humidity; landscapes; light intensity; modernization; plantations; species diversity; temperature; trees; India
Abstract:
... Although large areas of relatively undisturbed forests are essential for preserving biodiversity, opportunities for conservation in human-dominated landscapes must not be overlooked. Agroforestry systems such as shaded coffee plantations are known to be more compatible with biodiversity conservation than other, more drastic, land transformations. In recent times, however, modernization of coffee c ...
DOI:
10.1111/j.1469-1795.2007.00143.x

7. Aerodynamic Scaling for Estimating the Mean Height of Dense Canopies

Author:
Nakai, Taro; Sumida, Akihiro; Matsumoto, Kazuho; Daikoku, Ken'ichi; Iida, Shin'ichi; Park, Hotaek; Miyahara, Mie; Kodama, Yuji; Kononov, Alexander V.; Maximov, Trofim C.; Yabuki, Hironori; Hara, Toshihiko; Ohta, Takeshi
Source:
Boundary-layer meteorology 2008 v.128 no.3 pp. 423-443
ISSN:
0006-8314
Subject:
canopy; forest inventory; forests; linear models; roughness; trees; wind speed
Abstract:
... We used an aerodynamic method to objectively determine a representative canopy height, using standard meteorological measurements. The canopy height may change if the tree height is used to represent the actual canopy, but little work to date has focused on creating a standard for determining the representative canopy height. Here we propose the 'aerodynamic canopy height' h a as the most effectiv ...
DOI:
10.1007/s10546-008-9299-5

8. Age-size-habitat relationships for Polylepis australis: dealing with endangered forest ecosystems

Author:
Suarez, Ma. Laura; Renison, Daniel; Marcora, Paula; Hensen, Isabell
Source:
Biodiversity and conservation 2008 v.17 no.11 pp. 2617-2625
ISSN:
0960-3115
Subject:
tree growth; growth rings; canopy; endangered species; montane forests; tree age; rocks; subtropics; models; soil; tree and stand measurements; trees; watersheds; forest ecosystems; tree damage; Argentina
Abstract:
... Assessing tree ages is important for the understanding of forest recruitment patterns and tree growth. However, little experience exists in the subtropics and accurate aging usually involves potentially damaging techniques such as tree coring or even the use of entire cross sections, which is not recommendable in endangered species or ecosystems. We provide an example of how age may be predicted o ...
DOI:
10.1007/s10531-008-9336-1

9. Agricultural applications of a low-cost infrared thermometer

Author:
Mahan, James R.; Yeater, Kathleen M.
Source:
Computers and electronics in agriculture 2008 v.64 no.2 pp. 262-267
ISSN:
0168-1699
Subject:
canopy; agricultural research; radiometry; thermometers; cost effectiveness; agricultural machinery and equipment
Abstract:
... Plant canopy temperature is used in many studies of plant/environment interactions and non-contact measurement is often made with radiometric surface thermometers commonly referred to as infrared thermometers. Industrial-quality infrared thermocouples are widely available and often used in agricultural research. While research on canopy temperature has provided management tools for production agri ...
Handle:
10113/32440
DOI:
10.1016/j.compag.2008.05.017

10. Algal response to nutrient enrichment in forested oligotrophic stream

Author:
Veraart, Annelies J.; Romaní, Anna M.; Tornés, Elisabet; Sabater, Sergi
Source:
Journal of phycology 2008 v.44 no.3 pp. 564-572
ISSN:
0022-3646
Subject:
Achnanthes; Amphora; Cyanobacteria; Gomphonema; Rhoicosphenia; biofilm; biomass; canopy; ceramics; community structure; epiphytes; nitrogen; nutrient content; nutrients; phosphorus; physicochemical properties; seasonal variation; species diversity; spring; stream channels; tiles; trees; water flow
Abstract:
... Nutrient input in streams alters the density and species composition of attached algal communities in open systems. However, in forested streams, the light reaching the streambed (rather than the local nutrient levels) may limit the growth of these communities. A nutrient-enrichment experiment in a forested oligotrophic stream was performed to test the hypothesis that nutrient addition has only mi ...
DOI:
10.1111/j.1529-8817.2008.00503.x

11. Alien species importance in native vegetation along wadeable streams, John Day River basin, Oregon, USA

Author:
Magee, Teresa K.; Ringold, Paul L.; Bollman, Michael A.
Source:
Plant ecology 2008 v.195 no.2 pp. 287-307
ISSN:
1385-0237
Subject:
canopy; dry forests; environmental factors; floodplains; grazing intensity; indigenous species; introduced species; meadows; monitoring; multidimensional scaling; roads; shrublands; species diversity; streams; trees; watersheds; Oregon
Abstract:
... We evaluated the importance of alien species in existing vegetation along wadeable streams of a large, topographically diverse river basin in eastern Oregon, USA; sampling 165 plots (30 x 30 m) across 29 randomly selected 1-km stream reaches. Plots represented eight streamside community types associated with varying elevation, precipitation, and landform. Mantel comparisons, non-metric multidimens ...
DOI:
10.1007/s11258-007-9330-9

12. Ambient UV-B radiation decreases photosynthesis in high arctic Vaccinium uliginosum

Author:
Albert, Kristian R.; Mikkelsen, Teis N.; Ro-Poulsen, Helge
Source:
Physiologia plantarum 2008 v.133 no.2 pp. 199-210
ISSN:
0031-9317
Subject:
harvest date; canopy; energy; Calvin cycle; fluorescence; gas exchange; leaf area; light intensity; carbon; Vaccinium uliginosum; growing season; photosystem II; biomass; ultraviolet radiation; Greenland
Abstract:
... An UV-B-exclusion experiment was established in high arctic Zackenberg, Northeast Greenland, to investigate the possible effects of ambient UV-B on plant performance. During almost a whole growing season, canopy gas exchange and Chl fluorescence were measured on Vaccinium uliginosum (bog blueberry). Leaf area, biomass, carbon, nitrogen and UV-B-absorbing compounds were determined from a late seaso ...
DOI:
10.1111/j.1399-3054.2008.01065.x
PubMed:
18312501

13. Ammonia Emissions from Surface Flow and Subsurface Flow Constructed Wetlands Treating Dairy Wastewater

Author:
A. C. VanderZaag; R. J. Gordon; D. L. Burton; R. C. Jamieson; G. W. Stratton
Source:
Journal of environmental quality 2008 v.37 no.6 pp. 2028-2036
ISSN:
1537-2537
Subject:
gas emissions; ammonia; subsurface flow; overland flow; constructed wetlands; dairy cattle; wastewater treatment; volatilization; pollution load; ammonium nitrogen; canopy; Typha latifolia; vegetation; temperature; Nova Scotia
Abstract:
... Agricultural wastewater treatment is important for maintaining water quality, and constructed wetlands (CW) can be an effective treatment option. However, some of the N that is removed during treatment can be volatilized to the atmosphere as ammonia (NH₃). This removal pathway is not preferred because it negatively impacts air quality. The objective of this study was to assess NH₃ volatilization f ...
DOI:
10.2134/jeq2008.0021
PubMed:
18948455

14. Ammonia volatilization following application of pig slurry increases with slurry interception by grass foliage

Author:
Rochette, P.; Guilmette, D.; Chantigny, M.H.; Angers, D.A.; MacDonald, J.D.; Bertrand, N.; Parent, L.E.; Cote, D.; Gasser, M.O.
Source:
Canadian journal of soil science 2008 v.88 no.4 pp. 585-593
ISSN:
0008-4271
Subject:
ammonia; application timing; canopy; nitrogen content; soil surface sealing; slurries; volatilization; animal manure management; foliar application; infiltration (hydrology); soil air; forage grasses; liquid manure; gas emissions; odor emissions; pig manure; Quebec
DOI:
10.4141/CJSS07083

15. Analysis of long-term dynamics of crowns of sessile oaks at the stand level by means of spatial statistics

Author:
Longuetaud, Fleur; Seifert, Thomas; Leban, Jean-Michel; Pretzsch, Hans
Source:
Forest ecology and management 2008 v.255 no.5-6 pp. 2007-2019
ISSN:
0378-1127
Subject:
Quercus petraea; forest trees; canopy; stems; tree crown; spatial distribution; equations; vegetation cover; forest stands; spatial data; forest thinning; statistical analysis
Abstract:
... We analysed crown dynamics at the stand level in three plots of an even-aged sessile oak stand (one unthinned reference plot and two plots of different thinning intensities) of a long-term experiment in Rhineland Palatinate, Germany. Crown projections and stem locations were recorded in 1977, 1994 and 2004. Spatial structures of stems and crowns were analysed using the index of Clark and Evans and ...
DOI:
10.1016/j.foreco.2008.01.003

16. Analysis of maize canopy development under water stress and incorporation into the ADEL-Maize model

Author:
Song, Youhong; Birch, Colin; Hanan, Jim
Source:
Functional plant biology 2008 v.35 no.9-10 pp. 925-935
ISSN:
1445-4408
Subject:
crop models; Zea mays; canopy; plant growth; simulation models; plant architecture; corn; drought; water stress; dry matter accumulation; model validation; duration; field experimentation; leaves; Queensland
Abstract:
... Substantial progress in modelling crop architecture has been made under optimal watering conditions; however, crop production is often exposed to water stress. In this research, we develop methods for implementing the simulation of maize (Zea mays L.) canopy architectural development under water stress using data from a maize field trial in 2006-07. Data of leaf number, leaf and internode extensio ...
DOI:
10.1071/FP08055

17. Analysis of vegetation indices derived from hyperspectral reflection measurements for estimating crop canopy parameters of oilseed rape (Brassica napus L.)

Author:
Muller, Karla; Bottcher, Ulf; Meyer-Schatz, Franziska; Kage, Henning
Source:
Biosystems engineering 2008 v.101 no.2 pp. 172-182
ISSN:
1537-5110
Subject:
Brassica napus; canopy; estimation; vegetation; winter; precision agriculture; field experimentation; reflectance; oilseed crops; Germany
Abstract:
... Vegetation indices (VIs), which are derived from hyperspectral measurements, may be useful non-destructive measures to estimate crop canopy parameters. A systematic analysis of the reflectance spectrum of winter oilseed rape (OSR) for the derivation of VIs has not been conducted yet. We therefore derived in our study VIs from 61 available wavebands of the spectral range from 400 nm to 1000 nm syst ...
DOI:
10.1016/j.biosystemseng.2008.07.004

18. Application of SEBAL Model for Mapping Evapotranspiration and Estimating Surface Energy Fluxes in South-Central Nebraska

Author:
Singh, R.K.; Irmak, A.; Irmak, S.; Martin, D.L.
Source:
Journal of irrigation and drainage engineering 2008 v.134 no.3 pp. 273-285
ISSN:
0733-9437
Subject:
estimation; harvest date; simulation models; prediction; evapotranspiration; canopy; calibration; spatial distribution; soil physical properties; growing season; seasonal variation; remote sensing; Landsat; algorithms; crops; Nebraska
DOI:
10.1061/(ASCE)0733-9437(2008)134:3(273)

19. Application of Spectral Remote Sensing for Agronomic Decisions

Author:
J. L. Hatfield; A. A. Gitelson; J. S. Schepers; C. L. Walthall
Source:
Agronomy journal 2008 v.100 no.Supplement_3 pp. S-117
ISSN:
0002-1962
Subject:
hyperspectral imagery; vegetation cover; crop yield; remote sensing; reflectance; decision making; interspecific variation; agronomy; plant-water relations; agricultural history; shape; leaves; image analysis; plant nutrition; temperature; crop management; satellites; canopy; nutritional status; chlorophyll; crops
Abstract:
... Remote sensing has provided valuable insights into agronomic management over the past 40 yr. The contributions of individuals to remote sensing methods have lead to understanding of how leaf reflectance and leaf emittance changes in response to leaf thickness, species, canopy shape, leaf age, nutrient status, and water status. Leaf chlorophyll and the preferential absorption at different wavelengt ...
Handle:
10113/43013
DOI:
10.2134/agronj2006.0370c

20. Application of narrow-band TBVI in estimating fruit yield in citrus

Author:
Ye, X.; Sakai, K.; Asada, S.; Sasao, A.
Source:
Biosystems engineering 2008 v.99 no.2 pp. 179-189
ISSN:
1537-5110
Subject:
vegetation; estimation; Citrus; yield monitoring; hyperspectral imagery; canopy; agricultural forecasts; correlation; band placement; simulation models; remote sensing; tree fruits; citrus fruits
Abstract:
... Recently, the two-band vegetation index (TBVI) has been developed as an alternative to the conventional normalised difference vegetation index (NDVI) for assessing various agricultural crop characteristics. The potential of the narrow-band TBVI derived from airborne hyperspectral imagery to predict fruit yield in citrus was examined in this paper. Hyperspectral images in 72 visible and near-infrar ...
DOI:
10.1016/j.biosystemseng.2007.09.016

21. Application of species richness estimators for the assessment of fungal diversity

Author:
Unterseher, Martin; Schnittler, Martin; Dormann, Carsten; Sickert, Andreas
Source:
FEMS microbiology letters 2008 v.282 no.2 pp. 205-213
ISSN:
0378-1097
Subject:
canopy; deciduous forests; fungal communities; fungi; multidimensional scaling; multivariate analysis; species diversity; surveys; trees
Abstract:
... Species richness and distribution patterns of wood-inhabiting fungi and mycetozoans (slime moulds) were investigated in the canopy of a Central European temperate mixed deciduous forest. Species richness was described with diversity indices and species-accumulation curves. Nonmetrical multidimensional scaling was used to assess fungal species composition on different tree species. Different specie ...
DOI:
10.1111/j.1574-6968.2008.01128.x

22. Arboreal Ant Abundance and Leaf Miner Damage in Coffee Agroecosystems in Mexico

Author:
De la Mora, Aldo; Livingston, George; Philpott, Stacy M.
Source:
Biotropica 2008 v.40 no.6 pp. 742-746
ISSN:
0006-3606
Subject:
Azteca; agrochemicals; agroecosystems; canopy; ecosystem services; environmental factors; herbivores; leaves; nests; parasitic wasps; plantations; predators; pruning; shade trees; vegetation; Mexico
Abstract:
... Shaded coffee agroecosystems traditionally have few pest problems potentially due to higher abundance and diversity of predators of herbivores. However, with coffee intensification (e.g., shade tree removal or pruning), some pest problems increase. For example, coffee leaf miner outbreaks have been linked to more intensive management and increased use of agrochemicals. Parasitic wasps control the ...
DOI:
10.1111/j.1744-7429.2008.00444.x

23. Architectural modelling of maize under water stress

Author:
Birch, Colin J.; Thornby, David; Adkins, Steve; Andrieu, Bruno; Hanan, Jim
Source:
Animal production science 2008 v.48 no.3 pp. 335-341
ISSN:
0816-1089
Subject:
Zea mays; corn; field experimentation; irrigated farming; dryland farming; plant development; plant architecture; water stress; drought; canopy; leaf area; ontogeny; growth models; dry matter accumulation; grain yield; Queensland
Abstract:
... Two field experiments using maize (Pioneer 31H50) and three watering regimes [(i) irrigated for the whole crop cycle, until anthesis, (ii) not at all (experiment 1) and (iii) fully irrigated and rain grown for the whole crop cycle (experiment 2)] were conducted at Gatton, Australia, during the 2003-04 season. Data on crop ontogeny, leaf, sheath and internode lengths and leaf width, and senescence ...
DOI:
10.1071/EA06105

24. Are small sedentary species affected by habitat fragmentation? Local vs. landscape factors predicting species richness and composition of land molluscs in Swedish conservation forests

Author:
Götmark, Frank; von Proschwitz, Ted; Franc, Niklas
Source:
Journal of biogeography 2008 v.35 no.6 pp. 1062-1076
ISSN:
0305-0270
Subject:
altitude; canopy; climate; forests; habitat fragmentation; landscapes; microhabitats; pH; plant litter; prediction; slugs; snails; space and time; species diversity; temperature; trees; woodlands; Sweden
Abstract:
... To investigate the relative role of local versus landscape factors for local species diversity of snails and slugs in conservation forests. In landscapes with small, isolated patches of semi-natural habitats, many species that require large habitat areas have disappeared or are threatened. We asked whether small sedentary taxa that depend on local conditions, such as molluscs, are affected if tota ...
DOI:
10.1111/j.1365-2699.2008.01882.x

25. Arthropod community diversity and trophic structure: a comparison between extremes of plant stress

Author:
Trotter, R.T. III; Cobb, N.S.; Whitham, T.G.
Source:
Ecological entomology 2008 v.33 no.1 pp. 1-11
ISSN:
0307-6946
Subject:
arthropod communities; species diversity; population density; community structure; trophic relationships; Pinus edulis; canopy; plant stress; water stress; drought; Arizona
Abstract:
... 1. Previous studies have shown that plant stress and plant vigour impact the preference and performance of many insect species. Global climate-change scenarios suggest that some regions such as continental interiors may become increasingly subject to severe drought. In combination, these two issues suggest that drought-driven plant stress may impact insect communities on a landscape scale. While t ...
Handle:
10113/14236
DOI:
10.1111/j.1365-2311.2007.00941.x

26. Assessing effects of laser point density, ground sampling intensity, and field sample plot size on biophysical stand properties derived from airborne laser scanner data

Author:
Gobakken, T.; Naesset, E.
Source:
Canadian journal of forest research = 2008 v.38 no.5 pp. 1095-1109
ISSN:
0045-5067
Subject:
Monte Carlo method; canopy; lasers; volume; tree and stand measurements; height; forest stands; forest inventory; remote sensing; density; stand basal area; accuracy
Abstract:
... Canopy height distributions were created from small-footprint airborne laser scanner data with an average sampling density of 1.13 points·m-2 collected over 132 sample plots and 61 forest stands. Field measurements of each plot were carried out within two concentric circles corresponding to fixed areas of 200 m2 and 300 or 400 m2. The laser point clouds were thinned to approximately 0.25, 0.13, an ...
DOI:
10.1139/X07-219

27. Assessing factors that influence spatial variations in duff moisture

Author:
Raaflaub, L.D.; Valeo, C.
Source:
Hydrological processes 2008 v.22 no.15 pp. 2874-2883
ISSN:
0885-6087
Subject:
canopy; forest litter; montane forests; organic matter; trees
Abstract:
... Patterns and spatial variations in the moisture of the decomposing organic matter on the forest floor (the duff) of a montane forest were analysed in an effort to determine the primary factors shaping these patterns. Above and below canopy meteorological conditions were monitored to determine the influence of canopy cover on duff moisture. The spatial and temporal distributions of duff moisture we ...
DOI:
10.1002/hyp.7075

28. Assessing the relationships between stand development and understory vegetation using a 420-year chronosequence

Author:
Jules, Maureen J.; Sawyer, John O.; Jules, Erik S.
Source:
Forest ecology and management 2008 v.255 no.7 pp. 2384-2393
ISSN:
0378-1127
Subject:
land use change; logging; correlation; canopy; age structure; botanical composition; forest stands; stand characteristics; forest plantations; understory; Oregon
Abstract:
... The large-scale conversion of old forests to tree plantations has made it increasingly important to understand how understory vegetation responds to such landscape changes. For instance, in some forest types a reduction in understory richness and cover is thought to result from the development of canopy closure in plantations, although there is a paucity of empirical data demonstrating this relati ...
DOI:
10.1016/j.foreco.2007.12.042

29. Assessing the vulnerability of riparian vegetation to invasion by Mimulus guttatus: relative importance of biotic and abiotic variables in determining species occurrence and abundance

Author:
Truscott, A.-M.; Palmer, S.C.F.; Soulsby, C.; Hulme, P.E.
Source:
Diversity & distributions 2008 v.14 no.2 pp. 412-421
ISSN:
1366-9516
Subject:
sediments; canopy; rivers; stems; ecological invasion; grazing; habitats; environmental factors; trees; vegetation; soil water; watersheds; ecosystems; colonizing ability; Erythranthe guttata; introduced plants; Scotland
Abstract:
... Riparian habitats are particularly susceptible to invasion by non-native plants. At present, attempts to build consensus as to what the primary drivers of plant invasion in riparian ecosystems might be is hindered by the absence of common standards for data collected on plant species (e.g. occurrence, or relative abundance). Mimulus guttatus L., a non-native riparian plant species, was used as a m ...
DOI:
10.1111/j.1472-4642.2007.00449.x

30. Assessment of environmental impacts of a colony of free-ranging rhesus monkeys (Macca mulatta) on Morgan Island, South Carolina

Author:
Klopchin, Jeanette L.; Stewart, Jill R.; Webster, Laura F.; Sandifer, Paul A.
Source:
Environmental monitoring and assessment 2008 v.137 no.1-3 pp. 301-313
ISSN:
0167-6369
Subject:
DNA fingerprinting; Escherichia coli; Macaca mulatta; ammonia; basins; canopy; coliform bacteria; dissolved oxygen; environmental assessment; environmental impact; geographic information systems; monkeys; nutrients; orthophosphates; remote sensing; salinity; streams; temperature; vegetation; water quality; South Carolina
Abstract:
... Morgan Island, located within the ACE Basin National Estuarine Research Reserve in South Carolina, is home to the only free-ranging colony of rhesus monkeys (Macca mulatta) in the continental United States. The purpose of this study was to assess environmental impacts of the monkey colony on water quality in adjacent tidal creeks and on island vegetation. Three tidal creeks were sampled: Morgan Cr ...
DOI:
10.1007/s10661-007-9766-3

31. Assessment of the V45 Blueberry Harvester on Rabbiteye Blueberry and Southern Highbush Blueberry Pruned to V-Shaped Canopy

Author:
Takeda, F.; Krewer, G.; Andrews, E.L.; Mullinix, B. Jr.; Peterson, D.L.
Source:
HortTechnology 2008 v.18 no.1 pp. 130-138
ISSN:
1063-0198
Subject:
cultivars; canopy; Vaccinium virgatum; fruit quality; crop yield; Vaccinium darrowii; fruit harvesters; postharvest injuries; pruning; mechanical harvesting; crop management; blueberries; Vaccinium corymbosum; Georgia
Abstract:
... Mechanical harvesting systems for processed blueberries (Vaccinium spp.) are available. However, low harvest efficiency and high fruit damage have limited the use of mechanical harvesters for picking blueberries for fresh market to specific cultivars under good weather conditions. New harvesting technology for fresh-market blueberries is needed. The V45 harvester was developed by the U.S. Departme ...
Handle:
10113/15767

32. Assessment of the water status of mandarin and peach canopies using visible multispectral imagery

Author:
Kriston-Vizi, Janos; Umeda, Mikio; Miyamoto, Kumi
Source:
Biosystems engineering 2008 v.100 no.3 pp. 338-345
ISSN:
1537-5110
Subject:
Citrus unshiu; mandarins; canopy; fruit trees; peaches; water stress; plant stress; leaves; image analysis; orchards; near-infrared spectroscopy; leaf water potential; precision agriculture; irrigation management; simulation models; Prunus persica; Japan
Abstract:
... The production of high-quality mandarin or peach fruits depends on the ability to maintain an optimal level of water stress in the plant during the sugar accumulation period. This study investigates the use of visible imaging for monitoring water stress. Experiments were conducted on satsuma mandarin (Citrus unshiu Marc. var. Satsuma) and peach (Persica vulgaris Mill.) in south-western Japan. Wate ...
DOI:
10.1016/j.biosystemseng.2008.04.001

33. Association of reduced riparian vegetation cover in agricultural landscapes with coarse detritus dynamics in lowland streams

Author:
Reid, D.J.; Lake, P.S.; Quinn, G.P.; Reich, P.
Source:
Marine & freshwater research 2008 v.59 no.11 pp. 998-1014
ISSN:
1323-1650
Subject:
agricultural land; aquatic ecosystems; aquatic habitat; canopy; floodplains; overstory; streams; traps; trees; vegetation cover; Australia
Abstract:
... Studies were conducted on streams flowing through agricultural floodplains in south-eastern Australia to quantify whether reductions in riparian canopy cover were associated with alterations to the input and benthic standing stocks of coarse allochthonous detritus. Comparisons were made among three farmland reaches and three reaches within reserves with intact cover of remnant overstorey trees. De ...
DOI:
10.1071/MF08012

34. Automation of a Center Pivot Using the Temperature-Time-Threshold Method of Irrigation Scheduling

Author:
Peters, R.T.; Evett, S.R.
Source:
Journal of irrigation and drainage engineering 2008 v.134 no.3 pp. 286-291
ISSN:
0733-9437
Subject:
irrigation scheduling; automation; temperature; duration; thermometers; remote sensing; leaves; crops; canopy; growing season; water content; soybeans; Glycine max; water use efficiency; Texas
Abstract:
... A center pivot was completely automated using the temperature-time-threshold method of irrigation scheduling. An array of infrared thermometers was mounted on the center pivot, and these were used to remotely determine the crop leaf temperature as an indicator of crop water stress. We describe methods used to automatically collect and analyze the canopy temperature data and control the moving irri ...
Handle:
10113/18197
DOI:
10.1061/(ASCE)0733-9437(2008)134:3(286)

35. Avian life-history determinants of local extinction risk in a hyper-fragmented neotropical forest landscape

Author:
Lees, A.C.; Peres, C.A.
Source:
Animal conservation 2008 v.11 no.2 pp. 128-137
ISSN:
1367-9430
Subject:
anthropogenic activities; birds; canopy; deforestation; extinction; frugivores; habitat destruction; habitat fragmentation; insectivores; landscapes; life history; risk; species diversity; territoriality; tropical forests; Amazonia
Abstract:
... The fact that species vary in their vulnerability to extinction is well documented, but the reasons for these differences remain poorly understood. Why should some species/families/guilds decline rapidly with increasing anthropogenic disturbance, while others either tolerate or proliferate in disturbed habitats? We investigated the bird species composition in 31 primary forest patches of varying s ...
DOI:
10.1111/j.1469-1795.2008.00162.x

36. Baseline assessment for environmental services payments from satellite imagery: A case study from Costa Rica and Mexico

Author:
Kalacska, M.; Sanchez-Azofeifa, G.A.; Rivard, B.; Calvo-Alvarado, J.C.; Quesada, M.
Source:
Journal of environmental management 2008 v.88 no.2 pp. 348-359
ISSN:
0301-4797
Subject:
ecosystems; public services and goods; satellites; remote sensing; tropical forests; vegetation cover; canopy; accuracy; cartography; deciduous forests; deforestation; forest policy; environmental policy; ecosystem services; Costa Rica; Mexico
DOI:
10.1016/j.jenvman.2007.03.015

37. Belowground net primary productivity and biomass allocation of a grassland in Inner Mongolia is affected by grazing intensity

Author:
Gao, Ying Zhi; Giese, Marcus; Lin, Shan; Sattelmacher, Burkhard; Zhao, Ying; Brueck, Holger
Source:
Plant and soil 2008 v.307 no.1-2 pp. 41-50
ISSN:
0032-079X
Subject:
belowground biomass; biogeochemical cycles; biomass production; canopy; carbon; dry matter partitioning; grazing intensity; leaves; models; nutrients; permanent grasslands; primary productivity; root systems; semiarid zones; soil; steppes; China
Abstract:
... The root system of permanent grasslands is of outstanding importance for resource acquisition. Particularly under semi-arid conditions, the acquisition of water and nutrients is highly variable during the vegetation growth period and between years. Additionally, grazing is repeatedly disturbing the functional equilibrium between the root system and the transpiring leaf canopy. However, very few da ...
DOI:
10.1007/s11104-008-9579-3

38. Benthic metabolism on a sheltered rocky shore: role of the canopy in the carbon budget

Author:
Golléty, Claire; Migné, Aline; Davoult, Dominique
Source:
Journal of phycology 2008 v.44 no.5 pp. 1146-1153
ISSN:
0022-3646
Subject:
Ascophyllum nodosum; canopy; carbon; ecosystems; heterotrophs; metabolism; primary productivity; seasonal variation; temperature; understory; France
Abstract:
... While the importance of canopy-forming algae in structuring ecosystems is recognized, their role in the carbon budget is still not well understood. To our knowledge, no measurements of rocky shores primary production and respiration under emersion periods have been carried out in situ. A benthic chamber coupled to a CO₂-infrared gas analyzer was used to measure gross primary production and respira ...
DOI:
10.1111/j.1529-8817.2008.00569.x

39. Biodiversity and spatial distribution of vascular epiphytes in two biotopes of the Cameroonian semi-deciduous rain forest

Author:
Zapfack, Louis; Engwald, Stefan
Source:
Plant ecology 2008 v.195 no.1 pp. 117-130
ISSN:
1385-0237
Subject:
Orchidaceae; arid lands; biodiversity; biotopes; canopy; epiphytes; ferns and fern allies; forest types; laws and regulations; rain forests; trees; Cameroon
Abstract:
... The diversity and spatial distribution of vascular epiphytes were surveyed in two biotopes (dryland forest and swamp-inundated forest) of the semi-deciduous rain forest area in Cameroon. Eight sites in each biotope were selected, which included 530 individuals of phorophytes in dryland forest and 460 in swamp-inundated forest. A total of 148 epiphyte species were recorded, which showed that semi-d ...
DOI:
10.1007/s11258-007-9308-7

40. Biology and behaviour of reintroduced gibbons

Author:
Cheyne, Susan M.; Chivers, David J.; Sugardjito, Jito
Source:
Biodiversity and conservation 2008 v.17 no.7 pp. 1741-1751
ISSN:
0960-3115
Subject:
Hylobates; canopy; diet; human resources; humans; posture; social change; Borneo; Indonesia
Abstract:
... We observed and recorded the behaviours of gibbons undergoing rehabilitation, before and after release, to document the behavioural and social changes of gibbons in the rehabilitation program and develop criteria for determining the suitability of a pair of gibbons for release. Hylobates albibarbis were observed at the Kalaweit Gibbon Rehabilitation Project in Kalimantan, Indonesia. Data were coll ...
DOI:
10.1007/s10531-008-9378-4

41. Biomass allocation and leaf life span in relation to light interception by tropical forest plants during the first years of secondary succession

Author:
Galia Selaya, N.; Oomen, Roelof J.; Netten, Jordie J.C.; Werger, Marinus J.A.; Anten, Niels P.R.
Source:
Journal of ecology 2008 v.96 no.6 pp. 1211-1221
ISSN:
0022-0477
Subject:
Ochroma pyramidale; Trema; aboveground biomass; canopy; dry matter partitioning; forest litter; forest stands; leaf angle; leaf area index; leaves; lianas; longevity; models; secondary forests; secondary succession; shifting cultivation; trees; tropical rain forests
Abstract:
... 1. We related above-ground biomass allocation to light interception by trees and lianas growing in three tropical rain forest stands that were 0.5, 2 and 3-year-old regeneration stages after slash and burn agriculture. 2. Stem height and diameter, leaf angle, the vertical distribution of total above-ground biomass and leaf longevity were measured in individuals of three short-lived pioneers (SLP), ...
DOI:
10.1111/j.1365-2745.2008.01441.x

42. Biophysical controls on surface fuel litterfall and decomposition in the northern Rocky Mountains, USA

Author:
Keane, R.E.
Source:
Canadian journal of forest research = 2008 v.38 no.6 pp. 1431-1445
ISSN:
0045-5067
Subject:
leaf area index; height; correlation; stand basal area; forest fires; leaves; forest trees; relative humidity; soil organic matter; equations; fuels (fire ecology); temperature; branches; prediction; fire hazard reduction; canopy; forest litter; environmental factors; biodegradation; overstory; Rocky Mountain region; Idaho; Montana
Abstract:
... Litterfall and decomposition rates of the organic matter that comprise forest fuels are important to fire management, because they define fuel treatment longevity and provide parameters to design, test, and validate ecosystem models. This study explores the environmental factors that control litterfall and decomposition in the context of fuel management for several major forest types in the northe ...
Handle:
10113/18026
DOI:
10.1139/X08-003

43. Bird richness and composition along an agricultural gradient in New Guinea: The influence of land use, habitat heterogeneity and proximity to intact forest

Author:
MARSDEN, STUART J.; SYMES, CRAIG T.
Source:
Austral ecology 2008 v.33 no.6 pp. 784-793
ISSN:
1442-9985
Subject:
birds; canopy; correlation; forests; frugivores; habitat destruction; habitats; insectivores; land use; nectar feeding; principal component analysis; species diversity; surveys; trees; New Guinea
Abstract:
... We examined variation in bird species richness, abundance and guild composition along an agricultural gradient in New Guinea, and looked for any additive influence of habitat heterogeneity on these variables. The study was based on a grid of survey plots, six plots wide and 24 plots long with the long axis running from a settlement 2.4 km through active and abandoned agricultural plots towards a l ...
DOI:
10.1111/j.1442-9993.2008.01850.x

44. Boron deficiency and toxicity in young persimmon (Diospyrus kaki L.)

Author:
A. Bar-Tal; U. Yermiyahu; M. Keinan; I. Faingold; A. Ben-Gal
Source:
Journal of horticultural science & biotechnology 2008 v.83 no.4 pp. 469-473
ISSN:
2380-4084
Subject:
biomass production; biotechnology; boron; canopy; chlorosis; exposure duration; horticulture; irrigation; leaves; necrosis; nutrient solutions; persimmons; toxicity; trees
Abstract:
... Little information exists regarding boron (B) deficiency and toxicity in persimmon. The objective of this study was to quantify the response of young persimmon trees to a wide range of B concentrations – from deficiency to excess. Persimmon trees (Diospyrus kaki L. ‘Triumph’ on D. virginiana) were exposed to nutrient solutions containing B concentrations of 0.15, 0.33, 0.59, 1.01, 1.75, 2.75, 3.67 ...
DOI:
10.1080/14620316.2008.11512408

45. A Bowen Ratio Technique for Partitioning Energy Fluxes between Maize Transpiration and Soil Surface Evaporation

Author:
Adel T. Zeggaf; Shinichi Takeuchi; Hossein Dehghanisanij; Hisao Anyoji; Tomohisa Yano
Source:
Agronomy journal 2008 v.100 no.4 pp. 988-996
ISSN:
0002-1962
Subject:
Zea mays; evapotranspiration; canopy; correlation; soil water content; simulation models; accuracy; corn; transpiration; lysimeters; field experimentation; heat transfer; energy transfer; Japan
Abstract:
... A field experiment was conducted in 2005 at the experimental station of the Arid Land Research Center, Tottori University, Japan, for comparing latent heat fluxes from a maize (Zea mays L.) field, maize transpiration, and soil surface evaporation by two different methods. The Bowen ratio energy balance method (Method 1) was used to measure latent heat fluxes above the maize canopy as well as betwe ...
DOI:
10.2134/agronj2007.0201

46. Bundle Sheath Leakiness and Light Limitation during C₄ Leaf and Canopy CO₂ Uptake

Author:
Kromdijk, Johannes; Schepers, Hans E.; Albanito, Fabrizio; Fitton, Nuala; Carroll, Faye; Jones, Michael B.; Finnan, John; Lanigan, Gary J.; Griffiths, Howard
Source:
Plant physiology 2008 v.148 no.4 pp. 2144-2155
ISSN:
0032-0889
Subject:
Miscanthus; bundle sheath cells; canopy; carbon; crops; ecosystems; eddy covariance; energy; hybrids; isotopes; leaf area index; leaves; photosynthesis; temperate zones
Abstract:
... Perennial species with the C₄ pathway hold promise for biomass-based energy sources. We have explored the extent that CO₂ uptake of such species may be limited by light in a temperate climate. One energetic cost of the C₄ pathway is the leakiness ({phi}) of bundle sheath tissues, whereby a variable proportion of the CO₂, concentrated in bundle sheath cells, retrodiffuses back to the mesophyll. In ...
DOI:
10.1104/pp.108.129890
PubMed:
18971428
PubMed Central:
PMC2593657

47. CO₂ exchange of a tropical rainforest at Pasoh in Peninsular Malaysia

Author:
Kosugi, Yoshiko; Takanashi, Satoru; Ohkubo, Shinjiro; Matsuo, Naoko; Tani, Makoto; Mitani, Tomonori; Tsutsumi, Daizo; Nik, Abdul Rahim
Source:
Agricultural and forest meteorology 2008 v.148 no.3 pp. 439-452
ISSN:
0168-1923
Subject:
tropical rain forests; carbon dioxide; gas exchange; diurnal variation; soil respiration; leaf conductance; soil water content; canopy; solar radiation; air temperature; vapor pressure; water vapor; photosynthesis; dry season; seasonal variation; wet season; net ecosystem exchange; Malaysia
Abstract:
... The eddy covariance method was used to observe carbon dioxide flux (F c) for 3 years over an old-growth tropical rainforest at Pasoh in Peninsular Malaysia. The average nighttime F c and NEE were 3.6 and 4.7μmolm⁻² s⁻¹, respectively, when friction velocity (u * )>=0.2, while the average soil respiration rate measured occasionally with the chamber method was estimated to be 4.1μmolm⁻² s⁻¹ if we use ...
DOI:
10.1016/j.agrformet.2007.10.007

48. Calculating Dry Deposition and Canopy Exchange with the Canopy Budget Model: Review of Assumptions and Application to Two Deciduous Forests

Author:
Jeroen Staelens; Daniel Houle; An De Schrijver; Johan Neirynck; Kris Verheyen
Source:
Water, air, and soil pollution 2008 v.191 no.1-4 pp. 149-169
ISSN:
0049-6979
Subject:
labeling techniques; deciduous forests; canopy; simulation models; throughfall; ions; stemflow; dry deposition; Acer saccharum; Fagus sylvatica; Belgium; Quebec
Abstract:
... The canopy budget model simulates the interaction of major ions within forest canopies based on throughfall and precipitation measurements. The model has been used for estimating dry deposition and canopy exchange fluxes in a wide range of forest ecosystems, but different approaches have been reported. We give an overview of model variations with respect to the time step, type of open-field precip ...
DOI:
10.1007/s11270-008-9614-2

49. Calibration of an integrated land surface process and radiobrightness (LSP/R) model during summertime

Author:
Judge, J.; England, A.W.; Metcalfe, J.R.; McNichol, D.; Goodison, B.E.
Source:
Advances in water resources 2008 v.31 no.1 pp. 189-202
ISSN:
0309-1708
Subject:
Soil Vegetation Atmosphere Transfer models; summer; soil temperature; soil water; reflectance; vegetation; canopy; microwave radiation; remote sensing; South Dakota
DOI:
10.1016/j.advwatres.2007.08.006

50. Can complementarity in water use help to explain diversity-productivity relationships in experimental grassland plots

Author:
Verheyen, Kris; Bulteel, Hugo; Palmborg, Cecilia; Olivié, Bert; Nijs, Ivan; Raes, Dirk; Muys, Bart
Source:
Oecologia 2008 v.156 no.2 pp. 351-361
ISSN:
0029-8549
Subject:
biomass production; canopy; drought; evapotranspiration; grasslands; heat sums; soil resources; soil water; soil water balance; summer; surface temperature; water stress
Abstract:
... Positive diversity-productivity relationships have repeatedly been found in experimental grassland plots, but mechanistic explanations are still under debate. We tested whether complementarity for the exploitation of the soil water resource helps to explain these relationships. In the dry summer of 2003, evapotranspiration (ET) was assessed at the Swedish BIODEPTH site using two different approach ...
DOI:
10.1007/s00442-008-0998-x
PubMed:
18305961

51. Can spatial variation in epiphyte diversity and community structure be predicted from sampling vascular epiphytes alone?

Author:
Affeld, K.; Sullivan, J.; Worner, S.P.; Didham, R.K.
Source:
Journal of biogeography 2008 v.35 no.12 pp. 2274-2288
ISSN:
0305-0270
Subject:
Metrosideros; biomass; branches; canopy; coasts; community structure; environmental factors; epiphytes; flora; lichens; mosses and liverworts; non-vascular plants; roots; seedlings; species diversity; spores; surface area; trees; tropical rain forests; vascular plants; New Zealand
Abstract:
... Non-vascular epiphytes have been largely ignored in studies examining the biotic and abiotic determinants of spatial variation in epiphyte diversity. Our aim was to test whether the spatial patterning of species richness, biomass and community composition across geographic regions, among trees within regions, and among branches within trees is consistent between the vascular and non-vascular compo ...
DOI:
10.1111/j.1365-2699.2008.01949.x

52. A Canopy Architectural Model to Study the Competitive Ability of Chickpea with Sowthistle

Author:
Cici, S. Zahra-Hosseini; Adkins, Steve; Hanan, Jim
Source:
Annals of botany 2008 v.101 no.9 pp. 1311-1318
ISSN:
0305-7364
Subject:
Cicer arietinum; Sonchus oleraceus; canopy; chickpeas; cultivars; greenhouse experimentation; growth and development; models; plant architecture; plant competition; plant development; plant response; weed control
Abstract:
... BACKGROUND AND AIMS: Improving the competitive ability of crops is a sustainable method of weed management. This paper shows how a virtual plant model of competition between chickpea (Cicer arietinum) and sowthistle (Sonchus oleraceus) can be used as a framework for discovering and/or developing more competitive chickpea cultivars. METHODS: The virtual plant models were developed using the L-syste ...
DOI:
10.1093/aob/mcn040
PubMed:
18375962
PubMed Central:
PMC2710251

53. Canopy Characteristics and their Ability to Predict Peanut Maturity

Author:
Rowland, D.L.; Sorensen, R.B.; Butts, C.L.; Faircloth, W.H.; Sullivan, D.G.
Source:
Peanut science 2008 v.35 no.1 pp. 43-54
ISSN:
0095-3679
Subject:
Arachis hypogaea; peanuts; canopy; plant growth; harvest date; developmental stages; hulls; color; chlorophyll; chemical constituents of plants; solutes; nutrient content; plant nutrition; reflectance; brix; mathematical models; remote sensing; osmolality; Georgia
Abstract:
... To ensure maximum economic return, a peanut producer must accurately predict harvest time, delaying as long as possible to reach optimal crop maturity without risking losses through mechanical damage due to deteriorating peg attachments. Currently utilized methods for predicting peanut maturity are based on hull color determination and are labor-intensive and subject to the observer's ability to f ...
Handle:
10113/20170
DOI:
10.3146/PS06-052.1

54. Canopy assessment of biochemical features by ground-based hyperspectral data for an invasive species, giant reed (Arundo donax)

Author:
Ge, Shaokui; Carruthers, Raymond I.; Spencer, David F.; Yu, Qian
Source:
Environmental monitoring and assessment 2008 v.147 no.1-3 pp. 271-278
ISSN:
0167-6369
Subject:
image analysis; aquatic weeds; plant nutrition; canopy; nitrogen; Arundo donax; hyperspectral imagery; carbon; reflectance; remote sensing; invasive species; nutrients; chlorophyll; noxious weeds; nondestructive methods; Southwestern United States
Abstract:
... This study explored the potential use of hyperspectral data in the non-destructive assessment of chlorophyll, carbon, and nitrogen content of giant reed at the canopy level. We found that pseudoabsorption and derivatives of original hyperspectral data were able to describe the relationship between spectral data and measured biochemical characteristics. Based on correlogram analyses of ground-based ...
Handle:
10113/23065
DOI:
10.1007/s10661-007-0119-z

55. Canopy compass in nocturnal homing of the subsocial shield bug, Parastrachia japonensis (Heteroptera: Parastrachiidae)

Author:
Hironaka, Mantaro; Inadomi, Koichi; Nomakuchi, Shintaro; Filippi, Lisa; Hariyama, Takahiko
Source:
Naturwissenschaften 2008 v.95 no.4 pp. 343-346
ISSN:
0028-1042
Subject:
Heteroptera; canopy; foraging; habitats; insects; philopatry
Abstract:
... In contrast to an open environment where a specific celestial cue is predominantly used, visual contrast of canopies against the sky through the gap, known as canopy cues, is known to play a major role for visually guided insect navigators in woodland habitats. In this paper, we investigated whether a subsocial shield bug, Parastrachia japonensis, could gauge direction using canopy cues on a moonl ...
DOI:
10.1007/s00114-007-0324-1

56. Canopy effects of the invasive shrub Pyracantha angustifolia on seed bank composition, richness and density in a montane shrubland (Córdoba, Argentina)

Author:
GIANTOMASI, ALEJANDRA; TECCO, PAULA A.; FUNES, GUILLERMO; GURVICH, DIEGO E.; CABIDO, MARCELO
Source:
Austral ecology 2008 v.33 no.1 pp. 68-77
ISSN:
1442-9985
Subject:
Condalia montana; Pyracantha angustifolia; botanical composition; buried seeds; canopy; forbs; introduced species; invasive species; shrublands; shrubs; soil properties; woody plants; Argentina
Abstract:
... Invasive woody species frequently change the composition of the established vegetation and the properties of the soil under their canopies. Accordingly, invasion may well affect regenerative phases of the community, especially at the seed bank level, likely influencing community restoration. Pyracantha angustifolia (Rosaceae) is an invasive shrub in central Argentina that affects woody recruitment ...
DOI:
10.1111/j.1442-9993.2007.01791.x

57. Canopy nitrogen, carbon assimilation, and albedo in temperate and boreal forests: Functional relations and potential climate feedbacks

Author:
Ollinger, S.V.; Richardson, A.D.; Martin, M.E.; Hollinger, D.Y.; Frolking, S.E.; Reich, P.B.; Plourde, L.C.; Katul, G.G.; Munger, J.W.; Oren, R.; Smith, M.-L.; Paw U, K.T.; Bolstad, P.V.; Cook, B.D.; Day, M.C.; Martin, T.A.; Monson, R.K.; Schmid, H.P.
Source:
Proceedings of the National Academy of Sciences of the United States of America 2008 v.105 no.49 pp. 19336-19341
ISSN:
0027-8424
Subject:
canopy; nitrogen content; boreal forests; temperate forests; albedo (reflectance); conifer needles; spatial variation; remote sensing; photosynthesis; overstory; climatic factors; United States
Abstract:
... The availability of nitrogen represents a key constraint on carbon cycling in terrestrial ecosystems, and it is largely in this capacity that the role of N in the Earth's climate system has been considered. Despite this, few studies have included continuous variation in plant N status as a driver of broad-scale carbon cycle analyses. This is partly because of uncertainties in how leaf-level physio ...
Handle:
10113/22086
DOI:
10.1073/pnas.0810021105
PubMed:
19052233
PubMed Central:
PMC2593617

58. Canopy shade and the successional replacement of tamarisk by native box elder

Author:
Dewine, J.M.; Cooper, D.J.
Source:
Journal of applied ecology 2008 v.45 no.2 pp. 505-514
ISSN:
0021-8901
Subject:
tree growth; juvenility; canopy; shade tolerance; ecological succession; Acer negundo; shade; Tamarix; floodplains; canyons; invasive species; ecological invasion; tree mortality; Colorado
Abstract:
... 1. Tamarisk species (Tamarix ramosissima Ledeb., T. chinensis Lour., T. gallica L. and hybrids) have invaded riparian areas throughout western North America, resulting in expansive control efforts. Tamarisk is a relatively recent addition to North American plant communities, and competitive and successional processes are still developing. Box elder (Acer negundo L. var. interius (Britt.) Sarg.) is ...
DOI:
10.1111/j.1365-2664.2007.01440.x

59. Canopy snow influence on water and energy balances in a coniferous forest plantation in northern Japan

Author:
Suzuki, Kazuyoshi; Nakai, Yuichiro
Source:
Journal of hydrology 2008 v.352 no.1-2 pp. 126-138
ISSN:
0022-1694
Subject:
Abies sachalinensis; canopy; coniferous forests; snow; energy balance; evaporation; watershed hydrology; forest plantations; temperature; reflectance; Japan
Abstract:
... Snowfall captured by the forest canopy is an important component of the water and energy balances in forests that are seasonally covered with snow. In the present study, we examined the influence of canopy snow on water and energy balances above a coniferous forest in the Hitsujigaoka Experimental Forest of Japan during winter 1997-1998. Measured data comprised eddy covariance fluxes above the for ...
DOI:
10.1016/j.jhydrol.2008.01.007

60. Capturing diversity and interspecific variability in allometries: A hierarchical approach

Author:
Dietze, Michael C.; Wolosin, Michael S.; Clark, James S.
Source:
Forest ecology and management 2008 v.256 no.11 pp. 1939-1948
ISSN:
0378-1127
Subject:
allometry; statistical models; temperate forests; forest trees; tree crown; shape; height; canopy; tree and stand measurements; equations
Abstract:
... There is growing recognition of the role of mechanistic scaling laws in shaping ecological pattern and process. While such theoretical relationships explain much of the variation across large scales, at any particular scale there is important residual variation that is left unexplained among species, among individuals within a species, and within individuals themselves. Key questions remain on wha ...
DOI:
10.1016/j.foreco.2008.07.034

61. Carbon Isotope Fractionation during Photorespiration and Carboxylation in Senecio

Author:
Lanigan, Gary J.; Betson, Nicholas; Griffiths, Howard; Seibt, Ulli
Source:
Plant physiology 2008 v.148 no.4 pp. 2013-2020
ISSN:
0032-0889
Subject:
Senecio; air; canopy; carbon; carboxylation; diurnal variation; gas exchange; isotope fractionation; leaves; mesophyll; net ecosystem exchange; phosphoenolpyruvate carboxylase; photorespiration; ribulose-bisphosphate carboxylase
Abstract:
... The magnitude of fractionation during photorespiration and the effect on net photosynthetic ¹³C discrimination (Δ) were investigated for three Senecio species, S. squalidus, S. cineraria, and S. greyii. We determined the contributions of different processes during photosynthesis to Δ by comparing observations (Δobs) with discrimination predicted from gas-exchange measurements (Δpred). Photorespira ...
DOI:
10.1104/pp.108.130153
PubMed:
18923019
PubMed Central:
PMC2593675

62. Carbon dioxide exchange above a Mediterranean C3/C4 grassland during two climatologically contrasting years

Author:
AIRES, LUIS MIGUEL IGREJA; PIO, CASIMIRO ADRIÃO; PEREIRA, JOÃO SANTOS
Source:
Global change biology 2008 v.14 no.3 pp. 539-555
ISSN:
1354-1013
Subject:
C3 plants; C4 plants; Cynodon dactylon; canopy; carbon; carbon dioxide; carbon sequestration; carbon sinks; drought; ecosystem respiration; ecosystems; eddy covariance; grasses; grasslands; grazing; hydrology; leaf area index; net ecosystem exchange; photosynthesis; primary productivity; rain; spring; summer; warm season; winter; Portugal
Abstract:
... Eddy-covariance measurements of net ecosystem carbon exchange (NEE) were carried out above a grazed Mediterranean C3/C4 grassland in southern Portugal, during two hydrological years, 2004-2005 and 2005-2006, of contrasting rainfall. Here, we examine the seasonal and interannual variation in NEE and its major components, gross primary production (GPP) and ecosystem respiration (Reco), in terms of t ...
DOI:
10.1111/j.1365-2486.2007.01507.x

63. Carbon exchange and water use efficiency of a growing, irrigated olive orchard

Author:
Testi, Luca; Orgaz, Francisco; Villalobos, Francisco
Source:
Environmental and experimental botany 2008 v.63 no.1-3 pp. 168-177
ISSN:
0098-8472
Subject:
Olea europaea; olives; orchards; irrigated farming; carbon dioxide; gas exchange; carbon sequestration; water use efficiency; water vapor; leaf area index; soil respiration; solar radiation; cell respiration; diurnal variation; primary productivity; canopy; vapor pressure; photosynthesis; leaf conductance; microirrigation; net ecosystem exchange; Spain
Abstract:
... We measured eddy covariance fluxes of CO₂ and H₂O over a flat irrigated olive orchard during growth, in different periods from Leaf Area Index (LAI) of 0.3-1.9; measurements of soil respiration were also collected. The daily net ecosystem exchange flux (F NEE) was practically zero at LAI around 0.4 or when the orchard intercepted 11% of the incoming daily radiation; at the end of the experiment, w ...
DOI:
10.1016/j.envexpbot.2007.11.006

64. Carbon isotopes and water use efficiency: sense and sensitivity

Author:
Seibt, Ulli; Rajabi, Abazar; Griffiths, Howard; Berry, Joseph A.
Source:
Oecologia 2008 v.155 no.3 pp. 441-454
ISSN:
0029-8549
Subject:
canopy; carbon; climate change; environmental factors; gas exchange; growth rings; isotopes; leaves; mesophyll; models; prediction; trees; water use efficiency
Abstract:
... We revisit the relationship between plant water use efficiency and carbon isotope signatures (δ¹³C) of plant material. Based on the definitions of intrinsic, instantaneous and integrated water use efficiency, we discuss the implications for interpreting δ¹³C data from leaf to landscape levels, and across diurnal to decadal timescales. Previous studies have often applied a simplified, linear relati ...
DOI:
10.1007/s00442-007-0932-7
PubMed:
18224341

65. Changes in composition, structure and aboveground biomass over seventy-six years (1930-2006) in the Black Rock Forest, Hudson Highlands, southeastern New York State

Author:
Schuster, W.S.F.; Griffin, K.L.; Roth, H.; Turnbull, M.H.; Whitehead, D.; Tissue, D.T.
Source:
Tree physiology 2008 v.28 no.4 pp. 537-549
ISSN:
0829-318X
Subject:
temporal variation; deciduous forests; canopy; forest trees; forest succession; montane forests; stand basal area; forest stands; carbon sequestration; climate change; species diversity; forest inventory; stand composition; environmental factors; density; overstory; tree mortality; stand structure; understory; New York
Abstract:
... We sought to quantify changes in tree species composition, forest structure and aboveground forest biomass (AGB) over 76 years (1930-2006) in the deciduous Black Rock Forest in southeastern New York, USA. We used data from periodic forest inventories, published floras and a set of eight long-term plots, along with species-specific allometric equations to estimate AGB and carbon content. Between th ...
DOI:
10.1093/treephys/28.4.537
PubMed:
18244941

66. Changes in the field-layer of Wytham Woods –– assessment of the impacts of a range of environmental factors controlling change

Author:
Corney P. M.; Kirby K. J.; Le Duc M. G.; Smart S. M.; McAllister H. A.; Marrs R. H.
Source:
Journal of vegetation science 2008 v.19 no.3 pp. 287-298
ISSN:
1100-9233
Subject:
atmospheric deposition; botanical composition; canopy; climate change; data collection; deer; environmental factors; grasses; habitats; herbs; models; multivariate analysis; nitrogen; pollution load; synergism; woodlands; England
Abstract:
... Question: What are the impacts of factors controlling patterns of change in woodland field-layer vegetation, through time?Location: Wytham Woods, Oxford, UK (51°°41′′ N, 1°°19′′ W).Methods: Species occurrence was monitored in 163 permanent plots three times between 1973 and 2002 and related to management compartment and history. The dataset was analysed using a combination of ordination methods, u ...
DOI:
10.3170/2008-8-18383

67. Changes of dominant ground beetles in black pine forests with fire severity and successional age

Author:
Anselm Rodrigo; Francesc Sardà-Palomera; Jordi Bosch; Javier Retana
Source:
Écoscience 2008 v.15 no.4 pp. 442-452
ISSN:
2376-7626
Subject:
Carabidae; Pinus nigra; canopy; chronosequences; coniferous forests; fire intensity; fire severity; pitfall traps; shrubs; species diversity; vegetation cover; Spain
Abstract:
... This study analyzes the effect of fire on the composition and abundance of ground beetles in Pinus nigra forests. We used pitfall traps to sample beetles in burned P nigra forests in Catalonia (Spain). Since fire dramatically alters forest structure and composition and beetles follow vegetation changes, we expected drastic changes in beetle composition and abundance immediately after fire. Because ...
DOI:
10.2980/15-4-3117

68. Changes with seasonal flooding in sap flow of the tropical flood-tolerant tree species, Campsiandra laurifolia

Author:
Herrera, Ana; Tezara, Wilmer; Rengifo, Elizabeth; Flores, Saúl
Source:
Trees 2008 v.22 no.4 pp. 551-558
ISSN:
0931-1890
Subject:
Campsiandra; absorption; acclimation; adventitious roots; aeration; air; canopy; drainage; dry season; flooding tolerance; floods; forest trees; forests; hydraulic conductivity; leaf conductance; leaves; root hydraulic conductivity; sap flow; seasonal variation; stomatal conductance; water vapor; xylem water potential; Venezuela
Abstract:
... In order to determine how flooding affects sap flow and hydraulic conductivity of the tolerant species, Campsiandra laurifolia, trees growing in a tropical seasonally flooded forest in Venezuela were studied. We hypothesized that trees respond to rising-waters with a decrease in root-water absorption, caused by hypoxia, and stomatal conductance, and that this is reverted later on through a process ...
DOI:
10.1007/s00468-008-0215-x

69. Characteristics of canopy evapotranspiration from a small heterogeneous grassland using thermal imaging

Author:
Shimoda, Seiji; Oikawa, Takehisa
Source:
Environmental and experimental botany 2008 v.63 no.1-3 pp. 102-112
ISSN:
0098-8472
Subject:
grasslands; spatial variation; canopy; evapotranspiration; thermal analysis; image analysis; soil-plant-atmosphere interactions; landscapes; habitats; leaf area index; stomatal conductance; wind speed; solar radiation; soil water content; simulation models
Abstract:
... We used thermal imaging in conjunction with the eddy covariance technique to characterize canopy evapotranspiration (ET) from a small heterogeneous grassland. We compared ET estimated by a simple soil-vegetation-atmosphere transfer (SVAT) at field scale (a few 100m²) with that estimated by the eddy covariance method. These two independent estimates of ET showed a good correlation when the flux sou ...
DOI:
10.1016/j.envexpbot.2007.12.006

70. Climbing strategies determine light availability for both vines and associated structural hosts

Author:
Llorens, Anna-Maria; Leishman, Michelle R.
Source:
Australian journal of botany 2008 v.56 no.6 pp. 527-534
ISSN:
0067-1924
Subject:
height; roots; forests; shoots; interspecific variation; stems; growth habit; petioles; introduced plants; vines; host plants; leaf area; biomass; forest communities; understory; canopy; plant architecture; shade; indigenous species; light; New South Wales
Abstract:
... This study investigated biomass allocation traits and shading impact of vines (ground-rooted climbing plants) on their hosts in a tall open forest understorey community (Blue Gum High Forest) in Sydney, Australia. Eighty-six vine individuals from 11 species (7 natives and 4 exotics) were recorded and sampled on 26 individuals from 5 host species. All host species sampled were <3m in height. Each r ...
DOI:
10.1071/BT07019

71. Clonal Plasticity of Aquatic Plant Species Submitted to Mechanical Stress: Escape versus Resistance Strategy

Author:
Puijalon, Sara; Bouma, Tjeerd J.; Van Groenendael, Jan; Bornette, Gudrun
Source:
Annals of botany 2008 v.102 no.6 pp. 989-996
ISSN:
0305-7364
Subject:
Mentha aquatica; Potamogeton; aquatic plants; biomass; canopy; clonal variation; clones; mechanical stress; plant stress; stemflow; stems; water currents
Abstract:
... BACKGROUND AND AIMS: The plastic alterations of clonal architecture are likely to have functional consequences, as they affect the spatial distribution of ramets over patchy environments. However, little is known about the effect of mechanical stresses on the clonal growth. The aim of the present study was to investigate the clonal plasticity induced by mechanical stress consisting of continuous w ...
DOI:
10.1093/aob/mcn190
PubMed:
18854376
PubMed Central:
PMC2712407

72. Co-ordinated expression of amino acid metabolism in response to N and S deficiency during wheat grain filling

Author:
Howarth, Jonathan R.; Parmar, Saroj; Jones, Janina; Shepherd, Caroline E.; Corol, Delia-Irina; Galster, Aimee M.; Hawkins, Nathan D.; Miller, Sonia J.; Baker, John M.; Verrier, Paul J.; Ward, Jane L.; Beale, Michael H.; Barraclough, Peter B.; Hawkesford, Malcolm J.
Source:
Journal of experimental botany 2008 v.59 no.13 pp. 3675-3689
ISSN:
0022-0957
Subject:
filling period; proteins; canopy; biosynthesis; flowering; nitrogen content; nuclear magnetic resonance spectroscopy; glutamine; nitrogen; sulfur; fertilizers; biochemical pathways; Triticum aestivum; transcriptome; winter wheat; amino acid metabolism; sustainable agriculture; leaves; crops
Abstract:
... Increasing demands for productivity together with environmental concerns about fertilizer use dictate that the future sustainability of agricultural systems will depend on improving fertilizer use efficiency. Characterization of the biological processes responsible for efficient fertilizer use will provide tools for crop improvement under reduced inputs. Transcriptomic and metabolomic approaches w ...
DOI:
10.1093/jxb/ern218
PubMed:
18791197
PubMed Central:
PMC2561146

73. Comment on: Shukla, M.K. et al., 2006: Physical and chemical properties of soils under some pinon-juniper-oak canopies in a semi-arid ecosystem in New Mexico. J. Arid Environ. 66, 673-685

Author:
Mollerup, M.; Jensen, J.R.
Source:
Journal of arid environments 2008 v.72 no.4 pp. 579-580
ISSN:
0140-1963
Subject:
woodlands; semiarid zones; soil physical properties; soil chemical properties; canopy; plant available water; infiltration (hydrology); hydrologic models; mathematical models; equations
DOI:
10.1016/j.jaridenv.2007.08.009

74. Common Broomweed Growth Characteristics in Cleared and Woody Landscapes

Author:
Stanford Roy L.; Ansley R. James; Ransom Dean
Source:
Rangeland ecology & management 2008 v.61 no.5 pp. 561-565
ISSN:
1551-5028
Subject:
Colinus virginianus; height; plant density; vegetation cover; plant competition; woody weeds; forbs; perennials; wild plants; stems; wildlife habitats; ecological invasion; annuals; grasses; diameter; livestock; Prosopis glandulosa; canopy; Gutierrezia; Texas
Abstract:
... Common broomweed (Amphiachyris dracunculoides [[DC]] Nutt. Ex Rydb.) is an annual forb that occurs throughout the southern Great Plains, USA. During years of abundant growth, broomweed is problematic because it can reduce grass production and interfere with livestock foraging. In contrast, the canopy structure of broomweed may provide habitat cover for wildlife, including the northern bobwhite qua ...
DOI:
10.2111/08-012.1

75. Comparative demography of three coexisting Acer species in gaps and under closed canopy

Author:
Tanaka H.; Shibata M.; Masaki T.; Iida S.; Niiyama K.; Abe S.; Kominami Y.; Nakashizuka T.
Source:
Journal of vegetation science 2008 v.19 no.1 pp. 127-138
ISSN:
1100-9233
Subject:
Acer; canopy; deciduous forests; demography; fecundity; forest reserves; light requirement; models; population dynamics; seedlings; shade tolerance; survival rate; trees; Japan
Abstract:
... Questions: 1. Is there a trade-off between gap dependency and shade tolerance in each of the life-history stages of three closely related, coexisting species, Acer amoenum (Aa), A. mono (Am) and A. rufinerve (Ar)? 2. If not, what differences in life-history traits contribute to the coexistence of these non-pioneer species?Location: Ogawa Forest Reserve, a remnant (98 ha), species-rich, temperate d ...
DOI:
10.3170/2007-8-18342

76. Comparative measurements of transpiration and canopy conductance in two mixed deciduous woodlands differing in structure and species composition

Author:
Herbst, M.; Rosier, P.T.W.; Morecroft, M.D.; Gowing, D.J.
Source:
Tree physiology 2008 v.28 no.6 pp. 959-970
ISSN:
0829-318X
Subject:
deciduous forests; canopy; soil-plant-atmosphere interactions; stomatal conductance; soil water content; equations; microclimate; leaf area index; leaf area; sap flow; forest stands; weather; seasonal variation; stand composition; woodlands; stand structure; England
Abstract:
... Transpiration of two heterogeneous broad-leaved woodlands in southern England was monitored by the sap flux technique throughout the 2006 growing season. Grimsbury Wood, which had a leaf area index (LAI) of 3.9, was dominated by oak (Quercus robur L.) and birch (Betula pubescens L.) and had a continuous hazel (Corylus avellana L.) understory. Wytham Woods, which had an LAI of 3.6, was dominated by ...
DOI:
10.1093/treephys/28.6.959
PubMed:
18381276

77. Comparing Greenhouse Handgun Delivery to Poinsettias by Spray Volume and Quality

Author:
Derksen, Richard C.; Frantz, Jonathan; Ranger, Christopher M.; Locke, James C.; Zhu, Heping; Krause, Charles R.
Source:
Transactions of the ASABE 2008 v.51 no.1 pp. 27-35
Subject:
Euphorbia pulcherrima; greenhouse production; foliar spraying; spray deposition; canopy; leaves; spatial variation; droplet studies; pesticide application; insecticides; fungicides; sprayers
Abstract:
... Insecticide and fungicide labels often lack specific recommendations on the spray volume and spray droplet sizes that will provide the most efficacious pest management of ornamental pest problems. A greenhouse trial was established to determine differences in spray retention in a poinsettia canopy between single-nozzle, handgun applications made using three different spray volumes and three differ ...
Handle:
10113/19578

78. Comparing PLFA and amino sugars for microbial analysis in an Upper Michigan old growth forest

Author:
Liang, C.; Fujinuma, R.; Balser, T.C.
Source:
Soil biology & biochemistry 2008 v.40 no.8 pp. 2063-2065
ISSN:
0038-0717
Subject:
fatty acids; soil fungi; primary forests; soil bacteria; canopy; community structure; fatty acid composition; biomarkers; amino sugars; carbon sequestration; forest soils; biomass; phospholipids; Michigan
Abstract:
... Phospholipid fatty acid (PLFA) analysis and amino sugars analysis were compared with respect to their capacity to reliably indicate microbial biomass and gross community structure (e.g. fungi to bacteria ratio). We sampled three sets of soils beneath dominant canopy-tree species in an old growth forest and extracted them using both PLFA and amino sugars procedures. Amino sugars data had a lower co ...
DOI:
10.1016/j.soilbio.2008.01.022

79. Comparing geographic boundaries in songbird demography data with vegetation boundaries: a new approach to evaluating habitat quality

Author:
Hall, Kimberly R.
Source:
Environmental and ecological statistics 2008 v.15 no.4 pp. 491-521
ISSN:
1352-8505
Subject:
canopy; conifers; habitats; hardwood forests; males; managers; planning; sociodemographic characteristics; songbirds; understory; yearlings; Michigan
Abstract:
... To plan for the habitat needs of forest songbirds of conservation concern, managers need to understand how spatial heterogeneity in forest conditions influences habitat quality. I used difference boundary detection (wombling) and spatially constrained clustering to delineate boundaries in various combinations of four forest vegetation variables (understory height, understory density, percent decid ...
DOI:
10.1007/s10651-007-0065-5

80. Comparison of architecture among different cultivars of hybrid rice using a spatial light model based on 3-D digitising

Author:
Zheng, Bangyou; Shi, Lijuan; Ma, Yuntao; Deng, Qiyun; Li, Baoguo; Guo, Yan
Source:
Functional plant biology 2008 v.35 no.9-10 pp. 900-910
ISSN:
1445-4408
Subject:
cultivars; rice; plant development; canopy; simulation models; plant architecture; Oryza sativa; developmental stages; leaf area index; radiation use efficiency; shade; leaf angle; photosynthesis
Abstract:
... Modification of plant types (i.e. plant architecture) is an important strategy to enhance the yield potential of crops. The aims of this study were to specify rice plant types using 3-D modelling methodology. The architecture of three typical hybrid rice cultivars were measured in situ in a paddy field using a 3-D digitiser at four development stages from the panicle initiation to the filling stag ...
DOI:
10.1071/FP08060

81. Comparison of carbon and water vapor exchange of forest and grassland in permafrost regions, Central Yakutia, Russia

Author:
Lopez C., M.L.; Gerasimov, E.; Machimura, T.; Takakai, F.; Iwahana, G.; Fedorov, A.N.; Fukuda, M.
Source:
Agricultural and forest meteorology 2008 v.148 no.12 pp. 1968-1977
ISSN:
0168-1923
Subject:
carbon dioxide; simulation models; evapotranspiration; permafrost; boreal forests; water vapor; lakes; canopy; gas exchange; climate change; carbon sequestration; carbon; seasonal variation; surface water; overstory; grasslands; leaf conductance; Siberia
Abstract:
... Boreal grasslands have been largely neglected in carbon and water vapor flux models despite being originated by past global climate changes. Therefore in this study, meteorological conditions, water vapor and CO₂ fluxes were measured by the eddy correlation technique simultaneously in a larch forest and alas ecosystem (grassland thermokarst depression) in Central Yakutia, eastern Siberia, during t ...
DOI:
10.1016/j.agrformet.2008.09.013

82. Comparison of eddy covariance, chamber, and gradient methods of measuring soil CO₂ efflux in an annual semi-arid grass, Bromus tectorum

Author:
Myklebust, M.C.; Hipps, L.E.; Ryel, R.J.
Source:
Agricultural and forest meteorology 2008 v.148 no.11 pp. 1894-1907
ISSN:
0168-1923
Subject:
gas exchange; leaf area index; soil respiration; measurement; estimation; carbon dioxide; leaves; surface roughness; forage grasses; straw; accuracy; forage crops; canopy; Bromus tectorum; semiarid zones; net ecosystem exchange; snow; diurnal variation; vegetation; Idaho
Abstract:
... Eddy covariance measures net ecosystem exchange of CO₂ (NEE) at a scale between chamber-based measurements of CO₂ exchange processes and large-scale models of CO₂ flux dynamics. As the intermediate, it represents a link between small and large-scale estimates of NEE. Accuracy is therefore critical. However, estimates of nighttime ecosystem respiration based on scaled-up measurements of soil and le ...
DOI:
10.1016/j.agrformet.2008.06.016

83. Conservation value of timber quality versus associated non-timber quality stands for understory diversity in Nothofagus forests

Author:
Lencinas, María Vanessa; Martínez Pastur, Guillermo; Rivero, Paola; Busso, Carlos
Source:
Biodiversity and conservation 2008 v.17 no.11 pp. 2579-2597
ISSN:
0960-3115
Subject:
Nothofagus; biomass; canopy; forest types; landscape management; landscapes; lowland forests; multivariate analysis; overstory; species diversity; spring; stand management; summer; trees; understory; wetlands
Abstract:
... Conservation strategies of forested landscapes must consider biodiversity of the included site types, i.e. timber-quality forests and associated non-timber-quality stands. The objectives were to characterize forest overstory structure in timber-quality versus associated non-timber-quality stands; and to compare their understory communities. Six forest types were sampled in Nothofagus forests of Ti ...
DOI:
10.1007/s10531-008-9323-6

84. Constraints on transpiration of Eucalyptus globulus in southern Tasmania, Australia

Author:
O'Grady, Anthony P.; Worledge, Dale; Battaglia, Michael
Source:
Agricultural and forest meteorology 2008 v.148 no.3 pp. 453-465
ISSN:
0168-1923
Subject:
canopy; forest trees; stomatal conductance; soil water content; irrigation; Eucalyptus globulus; water use efficiency; leaf water potential; diurnal variation; rain; seasonal variation; summer; soil matric potential; forest plantations; hysteresis; leaf conductance; Tasmania
Abstract:
... The constraints on transpiration were studied in plantation grown Eucalyptus globulus trees over the summer of 2004/2005 at a research site in southern Tasmania. Diurnal patterns of leaf water potential and tree water use, measured using heat pulse techniques, were examined monthly in rain-fed and irrigated trees growing under similar atmospheric conditions. Soil matric potential declined during t ...
DOI:
10.1016/j.agrformet.2007.10.006

85. Contributions of woody and herbaceous vegetation to tropical savanna ecosystem productivity: a quasi-global estimate

Author:
Lloyd, J.; Bird, M.I.; Vellen, L.; Miranda, A.C.; Veenendaal, E.M.; Djagbletey, G.; Miranda, H.S.; Cook, G.; Farquhar, G.D.
Source:
Tree physiology 2008 v.28 no.3 pp. 451-468
ISSN:
0829-318X
Subject:
primary productivity; soil organic carbon; model validation; vegetation cover; C3 plants; forbs; interspecific variation; calibration; tropics; dry matter accumulation; savannas; soil fertility; woodlands; leaves; grasses; simulation models; C4 plants; botanical composition; woody plants; canopy; rain; Australia; Ghana; Brazil
DOI:
10.1093/treephys/28.3.451
PubMed:
18171668

86. Correlations of biotic and abiotic variables with ground surface temperature: An ectothermic perspective

Author:
Glenn M. Cunnington; James Schaefer; Joseph E. Cebek; Dennis Murray
Source:
Écoscience 2008 v.15 no.4 pp. 472-477
ISSN:
2376-7626
Subject:
canopy; correspondence analysis; forests; habitats; microprocessors; overstory; physiology; plant litter; roads; surface temperature; understory; urban areas; Ontario
Abstract:
... Temperature is often an important determinant of species presence and activity patterns, but observations of temperature at fine resolution and broad extents—scales relevant to individual organisms—are rare. We analyzed how biotic and abiotic variables influence ground surface temperature (GST) using high-resolution thermal data for a 1900–ha area of forest and field near Wasaga Beach, Ontario, Ca ...
DOI:
10.2980/15-4-3140

87. Coupling a 3D virtual wheat (Triticum aestivum) plant model with a Septoria tritici epidemic model (Septo3D): a new approach to investigate plant-pathogen interactions linked to canopy architecture

Author:
Robert, Corinne; Fournier, Christian; Andrieu, Bruno; Ney, Bertrand
Source:
Functional plant biology 2008 v.35 no.9-10 pp. 997-1013
ISSN:
1445-4408
Subject:
simulation models; Mycosphaerella graminicola; canopy; disease models; plant architecture; spore dispersal; fungal diseases of plants; spatial distribution; wheat; disease transmission; disease outbreaks; rain; plant pathogenic fungi; Triticum aestivum; climatic factors; leaves
Abstract:
... This work initiates a modelling approach that allows us to investigate the effects of canopy architecture on foliar epidemics development. It combines a virtual plant model of wheat (Triticum aestivum L.) with an epidemic model of Septoria tritici which is caused by Mycosphaerella graminicola, a hemi-biotrophic, splashed-dispersed fungus. Our model simulates the development of the lesions from the ...
DOI:
10.1071/FP08066

88. Coupling of canopy and understory food webs by ground-dwelling predators

Author:
Pringle, Robert M.; Fox-Dobbs, Kena
Source:
Ecology letters 2008 v.11 no.12 pp. 1328-1337
ISSN:
1461-023X
Subject:
arthropods; canopy; diet; ecosystems; energy; food webs; grasses; grasslands; habitats; insects; predators; shrubs; subsidies; trees; understory
Abstract:
... Understanding food-web dynamics requires knowing whether species assemblages are compartmentalized into distinct energy channels, and, if so, how these channels are structured in space. We used isotopic analyses to reconstruct the food web of a Kenyan wooded grassland. Insect prey were relatively specialized consumers of either C₃ (trees and shrubs) or C₄ (grasses) plants. Arboreal predators (arth ...
DOI:
10.1111/j.1461-0248.2008.01252.x
PubMed:
19046361

89. Crop growth and yield prediction using canopy reflectance – A review

Author:
M. Leelamathi; K.P. Rajendran; C. Gailce Leo Justin
Source:
Agricultural reviews 2008 v.29 no.4 pp. 290-297
ISSN:
0253-1496
Subject:
biomass; canopy; chlorophyll; crop yield; exports; imports; leaf area index; leaf reflectance; leaves; reflectance; soil salinity; toxicity; yield forecasting
Abstract:
... The reflecting power of crop canopy gets changed with plant species. The reflection from leaves increases with increasing soil salinity, leaf moisture deficit and chlorophyll content. Environmental factors such as soil salinity, moisture availability and nutrient toxicity or its deficiency affects the optical and radiation properties of plants. The reflection in the red spectral region from plant ...

90. Crop rotation effects on Cyperus rotundus and C. esculentus population dynamics in southern California vegetable production

Author:
WANG, G.; McGIFFEN Jr, M.E.; OGBUCHIEKWE, E.J.
Source:
Weed research 2008 v.48 no.5 pp. 420-428
ISSN:
0043-1737
Subject:
Brassica oleracea; Cucumis melo; Cyperus esculentus; Cyperus rotundus; Sorghum bicolor subsp. drummondii; Triticum aestivum; Zea mays; broccoli; canopy; cantaloupes; cover crops; crop rotation; crop yield; fallow; growing season; halosulfuron; planting; population dynamics; shade; soil; spring; spring wheat; summer; tubers; vegetable crops; vegetable growing; weeds; California
Abstract:
... Control options for Cyperus rotundus and Cyperus esculentus (purple and yellow nutsedge) were evaluated within three cropping systems in the low desert of southern California: (1) standard vegetable crop rotation (weed-free, uncontrolled nutsedge and cultivation) with spring cantaloupe (Cucumis melo) - summer fallow - winter broccoli (Brassica oleracea), (2) cover crop rotation (halosulfuron and s ...
DOI:
10.1111/j.1365-3180.2008.00649.x

91. Crop water stress index is a sensitive water stress indicator in pistachio trees

Author:
Testi, L.; Goldhamer, D. A.; Iniesta, F.; Salinas, M.
Source:
Irrigation science 2008 v.26 no.5 pp. 395-405
ISSN:
0342-7188
Subject:
canopy; deficit irrigation; diurnal variation; equations; evapotranspiration; field crops; fruit growing; irrigation rates; leaf water potential; orchards; pistachios; solar radiation; temperature; thermometers; transpiration; trees; vapor pressure; water stress; California
Abstract:
... Regulated deficit irrigation (RDI) strategies, often applied in tree crops, require precise monitoring methods of water stress. Crop water stress index (CWSI), based on canopy temperature measurements, has shown to be a good indicator of water deficits in field crops but has seldom been used in trees. CWSI was measured on a continuous basis in a Central California mature pistachio orchard, under f ...
DOI:
10.1007/s00271-008-0104-5

92. Cross-validating Sun-shade and 3D models of light absorption by a tree-crop canopy

Author:
Roupsard, Olivier; Dauzat, Jean; Nouvellon, Yann; Deveau, Aurélie; Feintrenie, Laurène; Saint-André, Laurent; Mialet-Serra, Isabelle; Braconnier, Serge; Bonnefond, Jean-Marc; Berbigier, Paul; Epron, Daniel; Jourdan, Christophe; Navarro, Muriel; Bouillet, Jean-Pierre
Source:
Agricultural and forest meteorology 2008 v.148 no.4 pp. 549-564
ISSN:
0168-1923
Subject:
simulation models; canopy; solar radiation; photosynthetically active radiation; tree crown; Cocos nucifera; plant architecture; leaf area index; leaf area; plant density; shade; coconuts; fruit crops; photosynthesis; leaves; Vanuatu
Abstract:
... Sun-shade models proved to be simple, fast and reliable tools for estimating the fraction of absorbed PAR (fAPAR) and the photosynthesis of low and simple canopies (e.g. wheat). Applications on tall canopies, or non-ideal canopies (e.g. row-planting, azimuthal heterogeneity, clumping, non-spherical leaf angle distribution, large proportion of non-green elements) were limited so far. We attempted t ...
DOI:
10.1016/j.agrformet.2007.11.002

93. Cultivar and rootstock response to drip irrigation in sweet cherry tree vigour and start of bearing during the first three years after planting

Author:
J. Blažková; I. Hlušičková
Source:
Zahradnictví v.35 no.2 pp. 72-82
ISSN:
0862-867X
Subject:
Prunus avium; Vanda; autumn; canopy; cultivars; flowers; fruits; microirrigation; rain; rootstocks; tree growth; vigor
Abstract:
... Fifteen sweet cherry cultivars and three rootstocks were evaluated within three years in two experimental orchards established in the same location in the autumn 2004. In one of them drip irrigation was applied in the periods of insufficient rainfall, i.e. from mid-April to mid-August. This irrigation distinctly increased the vigour of trees that was jointly expressed by trunk-cross-section area, ...
DOI:
10.17221/641-hortsci

94. Cyclone damage to tropical rain forests: Species- and community-level impacts

Author:
METCALFE, DANIEL J.; BRADFORD, MATT G.; FORD, ANDREW J.
Source:
Austral ecology 2008 v.33 no.4 pp. 432-441
ISSN:
1442-9985
Subject:
canopy; coasts; correlation; highlands; hurricanes; monitoring; storm damage; trees; tropical rain forests; tropics; wind speed; Queensland
Abstract:
... Severe Tropical Cyclone 'Larry' caused damage to 10 long-term 0.5 ha monitoring plots in the rain forests of Queensland's Wet Tropics on 20 March 2006. We assessed the community-level damage and the impact of the cyclone on the most abundant tree species in each plot. Damage was positively correlated with distance from the cyclone eye, though some plots received less damage than predicted owing to ...
DOI:
10.1111/j.1442-9993.2008.01898.x

95. Day roost characteristics of northern long-eared bats (Myotis septentrionalis) in relation to female reproductive status

Author:
Colin J. Garroway; Hugh G. Broders
Source:
Écoscience 2008 v.15 no.1 pp. 89-93
ISSN:
2376-7626
Subject:
Myotis septentrionalis; canopy; females; progeny; reproduction; resting periods; summer; trees
Abstract:
... In summer, females of most temperate bat species aggregate at maternity roosts, during which time females gestate, give birth, and wean offspring. These activities make the presence of suitable roosts critical for population persistence. Many studies have identified important roost tree characteristics by comparing roost trees to random trees. However, if bats select trees that facilitate either t ...
DOI:
10.2980/1195-6860(2008)15%5B89:DRCONL%5D2.0.CO;2

96. Decline of Cornus florida and forest succession in a Quercus-Carya forest

Author:
Pierce, Aaron R.; Bromer, William R.; Rabenold, Kerry N.
Source:
Plant ecology 2008 v.195 no.1 pp. 45-53
ISSN:
1385-0237
Subject:
Acer saccharum; Armillaria; Carya; Cornus florida; Discula destructiva; Quercus; anthropogenic activities; biogeochemical cycles; birds; canopy; decline; forest succession; forest surveys; fungi; hardwood forests; migratory behavior; pathogens; population dynamics; root rot; shade; survival rate; understory; Indiana
Abstract:
... Cornus florida is a common understory species in many hardwood forests in eastern North America. It plays an important role in nutrient cycling and is an important food resource for many vertebrate species, especially migratory birds. We used data collected over a 16-year period to examine population dynamics of a tagged population of C. florida in a 6.4 ha area in the context of change in the pro ...
DOI:
10.1007/s11258-007-9297-6

97. Deer density affects ground-layer vegetation differently in conifer plantations and hardwood forests on the Boso Peninsula, Japan

Author:
Suzuki, Maki; Miyashita, Tadashi; Kabaya, Hajime; Ochiai, Keiji; Asada, Masahiko; Tange, Takeshi
Source:
Ecological research 2008 v.23 no.1 pp. 151-158
ISSN:
0912-3814
Subject:
Cedrus; canopy; conifers; deer; forest ecosystems; forest management; forest plantations; hardwood; hardwood forests; herbivores; population density; soil water content; species diversity; vegetation cover; Japan
Abstract:
... Deer overabundance reduces forest ground-layer vegetation and can cause cascading impacts on a forest ecosystem. To predict these effects, we must elucidate the relationship between deer density and the status of ground-layer vegetation. This relationship was studied in the Boso Peninsula, where the deer population density exhibits a clear geographical gradient. We examined species richness and co ...
DOI:
10.1007/s11284-007-0348-1

98. The Demise of Fire and “Mesophication” of Forests in the Eastern United States

Author:
Nowacki, G.J.; Abrams, M.D.
Source:
BioScience 2008 v.58 no.2 pp. 123-138
ISSN:
0006-3568
Subject:
Pinus; Quercus; canopy; geospatial technology; shade tolerance; plant communities; hardwood forests; prescribed burning; savannas; forest ecosystems; forest fires; prairies; Eastern United States
Abstract:
... A diverse array of fire-adapted plant communities once covered the eastern United States. European settlement greatly altered fire regimes, often increasing fire occurrence (e.g., in northern hardwoods) or substantially decreasing it (e.g., in tallgrass prairies). Notwithstanding these changes, fire suppression policies, beginning around the 1920s, greatly reduced fire throughout the East, with pr ...
Handle:
10113/16509
DOI:
10.1641/B580207

99. Demographic variation in cycad populations inhabiting contrasting forest fragments

Author:
López-Gallego, Cristina
Source:
Biodiversity and conservation 2008 v.17 no.5 pp. 1213-1225
ISSN:
0960-3115
Subject:
canopy; fecundity; plant establishment; landscape management; Zamia; environmental factors; secondary forests; soil water; population density; conservation programs; habitat fragmentation; plant reproduction; population size; habitats
Abstract:
... Reduced habitat quality after fragmentation can significantly affect population viability, but the effects of differing quality of the remaining habitat on population fitness are rarely evaluated. Here, I compared fragmented populations of the cycad Zamia melanorrhachis from habitats with different history and subject to contrasting levels of disturbance to explore potential demographic difference ...
DOI:
10.1007/s10531-007-9263-6

100. Derivation of plant growth coefficients for the use in wind erosion models in argentina

Author:
Mariano J. Mendez; Daniel E. Buschiazzo
Source:
Soil science 2008 v.173 no.7 pp. 468-479
ISSN:
0038-075X
Subject:
wind erosion; soil erosion models; plant growth; crop models; Helianthus annuus; Zea mays; corn; crop residues; wind speed; mathematical models; equations; developmental stages; canopy; Argentina
Abstract:
... Relationships between wind erosion soil loss ratio (SLR, the quotient between the soil loss in a ground cover and a bare and smooth soil) and the percent of soil coverage with plant residues or canopy have been mostly obtained by means of wind tunnel experiments where fluid-dynamic parameters, driven in the nature by climatic conditions, can be maintained constant. To test the behavior of SLR unde ...
DOI:
10.1097/SS.0b013e31817b666c