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- Author:
- Roesch, Francis A.
- Source:
- Proceedings of the eighth annual Forest Inventory and Analysis Symposium : Monterey, CA, October 16-19, 2006 / edited by Ronald E. McRoberts ... [et al.] pp. -
- Subject:
- mercury; spatial distribution; soil organic matter; forest soils; soil pollution; chemical concentration; atmospheric deposition; forest litter; geographical distribution; ecoregions; spatial data; United States
- Abstract:
- ... The sample unit and its implications for the Forest Service, U.S. Department of Agriculture's Forest Inventory and Analysis program are discussed in light of a generalized three-dimensional concept of continuous forest inventories. The concept views the sampled population as a spatial-temporal cube and the sample as a finite partitioning of the cube. The sample serves to cut the volume of the cube ...
- Handle:
- 10113/42018
- Author:
- Bailey, Robert G.
- Source:
- Proceedings of the eighth annual Forest Inventory and Analysis Symposium : Monterey, CA, October 16-19, 2006 / edited by Ronald E. McRoberts ... [et al.] pp. -
- Subject:
- ecosystems; land management; vegetation structure; landscapes; landscape ecology; spatial data; climatic factors; landforms; geographical distribution; ecoregions; USDA Forest Service; research; models
- Abstract:
- ... This article discusses the origins of natural ecosystem patterns from global to local scales. It describes how understanding these patterns can help scientists and managers in two ways. First, the local systems are shown within the context of larger systems. This perspective can be applied in assessing the connections between action at one scale and effect at another, the spatial transferability o ...
- Handle:
- 10113/42020
- Author:
- A. W. Kuchler
- Source:
- Ecology 1973 v.54 no.3 pp. 512-523
- ISSN:
- 0012-9658
- Subject:
- biotopes; ecoregions; environmental factors; geographical distribution; humid tropics; plant communities; vegetation types; New South Wales
- Abstract:
- ... Important research carried on currently in ecological regionalization calls for a close look at the role of classifying and mapping vegetation, as both these activities can be of fundamental significance in regionalization. A correlation of classifying and mapping vegetation with ecological regions requires an analysis of vegetation, classifications, regions, and maps. The analysis of vegetation r ...
- DOI:
- 10.2307/1935336
- https://doi.org/10.2307/1935336
- Author:
- Gary W. Ferguson; Charles H. Bohlen; H. Patrick Woolley
- Source:
- Ecology 1980 v.61 no.2 pp. 313-322
- ISSN:
- 0012-9658
- Subject:
- Sceloporus undulatus; adults; autumn; clutch size; demography; ecoregions; females; grasslands; juveniles; life history; lizards; mortality; population size; predation; woodlands; Kansas
- Abstract:
- ... The demography of a small, isolated population of the lizard, Sceloporus undulatus garmani from eastern Kansas, USA was studied for 5 yr. Growth rates were relatively rapid; age of maturity, relatively low; clutch size was small and decreased in successive clutches of the same females; juvenile survival, while low, was high for the species; adult survival was relatively low. The population size wa ...
- DOI:
- 10.2307/1935190
- https://doi.org/10.2307/1935190
- Author:
- Source:
- Hydrological sciences journal 1985 v.30 no.2 pp. 239-256
- ISSN:
- 0262-6667
- Subject:
- Universal Soil Loss Equation; deforestation; economics; ecoregions; erodibility; grazing; landforms; pollution load; research and development; rivers; sediment transport; sediment yield; soil erosion; watersheds; Africa
- Abstract:
- ... This paper reviews the magnitude of soil erosion in tropical Africa and relates it to erodibility, erosivity and landform in different ecological regions There are few direct measurements of erosivity and erodibility in tropical Africa and the relevance of using the Universal Soil Loss Equation in estimating these parameters is reviewed. Soil erodibility is not a fixed parameter and changes with t ...
- DOI:
- 10.1080/02626668509490987
- https://doi.org/10.1080/02626668509490987
6. Reduced Postfire Tree Regeneration Along A Boreal Forest‐Forest‐Tundra Transect in Northern Quebec
- Author:
- Luc Sirois; Serge Payette
- Source:
- Ecology 1991 v.72 no.2 pp. 619-627
- ISSN:
- 0012-9658
- Subject:
- Picea mariana; boreal forests; deforestation; ecoregions; environmental impact; forest ecosystems; forest stands; global warming; highlands; lowlands; paleoecology; population density; shrubs; species recruitment; trees; tundra; wildfires; Quebec
- Abstract:
- ... The large 1950s fires that burned >5500 km² of land across a south—to—north climatic gradient in northern Quebec provide an opportunity to evaluate the role of fire in forest—tundra development on a demographic basis. The tree population density before and ° 30 yr after fire was estimated by censusing trees in plots of 400 m² located in upland and lowland within four representative ecoregions of n ...
- DOI:
- 10.2307/2937202
- https://doi.org/10.2307/2937202
- Author:
- B. L. Kerans; James R. Karr
- Source:
- Ecological applications 1994 v.4 no.4 pp. 768-785
- ISSN:
- 1051-0761
- Subject:
- Chironomidae; Corbicula; Ephemeroptera; Oligochaeta; Plecoptera; Trichoptera; analysis of variance; correlation; data collection; detritivores; ecoregions; fish; habitats; humans; industrial effluents; monitoring; mussels; omnivores; predators; quantitative analysis; rivers; snails; society; streams; water quality analysis; Tennessee
- Abstract:
- ... Invertebrate data from rivers in the Tennessee Valley were used to: (1) evaluate the utility of 18 characteristics of invertebrate assemblages (attributes) to assess the biological condition of streams and (2) develop a comprehensive benthic invertebrate index that reflects important aspects stream biology and responds to the effects of human society in detectable ways. We used data from the Tenne ...
- DOI:
- 10.2307/1942007
- https://doi.org/10.2307/1942007
8. A Laboratory Model for Studying Environmently Dependent Chemical Modifications in Textile Cellulose
- Author:
- Dmitri A. Kouznetsov; Andrey A. Ivanov; Pavel R. Veletsky; Vyacheslav L. Charsky; Oleg S. Beklemishev
- Source:
- Textile research journal 1996 v.66 no.2 pp. 111-114
- ISSN:
- 0040-5175
- Subject:
- acetylation; air; air flow; antibacterial properties; bacteria; carbon; cellulose; ecoregions; electrophoresis; enzyme activity; fabrics; filtration; forensic sciences; glucose; hydrolysates; methylation; microbial growth; models; radionuclides; sodium azide; stable isotopes; textile fibers; urea
- Abstract:
- ... We have developed a laboratory model to evaluate possible microbial impact on cellulose during long-term contact with air microorganisms. This model is based on the capillary zone electrophoretic /mass spectrometric estimation of modified glucose residues in cellulose enzymatic hydrolysates isolated from linen samples. We subjected these samples to a pump-directed air flow line for 8 days and 10 w ...
- DOI:
- 10.1177/004051759606600208
- https://doi.org/10.1177/004051759606600208
- Author:
- George E. Host; Philip L. Polzer; David J. Mladenoff; Mark A. White; Thomas R. Crow
- Source:
- Ecological applications 1996 v.6 no.2 pp. 608-618
- ISSN:
- 1051-0761
- Subject:
- Landsat; algorithms; analytical methods; data collection; databases; ecoregions; ecosystems; forest management; forests; geographic information systems; geology; land classification; landscapes; multivariate analysis; principal component analysis; soil; temperature; thematic maps; Wisconsin
- Abstract:
- ... Ecological land classification systems have recently been developed at continental, regional, state, and landscape scales. In most cases, the map units of these systems result from subjectively drawn boundaries, often derived by consensus and with unclear choice and weighting of input data. Such classifications are of variable accuracy and are not reliably repeatable. We combined geographic inform ...
- DOI:
- 10.2307/2269395
- https://doi.org/10.2307/2269395
- Author:
- Rubio-Palis, Y.; Zimmerman, R.H.
- Source:
- Journal of medical entomology 1997 v.34 no.5 pp. 499-510
- ISSN:
- 0022-2585
- Subject:
- Anopheles; disease vectors; malaria; classification; environmental factors; geographical distribution; vector control; ecoregions; Central America; South America
- Abstract:
- ... An ecoregional approach to the classification of malaria in the neotropics region can give health personnel a new perspective on how to manage malaria control programs. We propose an ecoregional classification based on vector distribution and important environmental determinants, including vegetation type, rainfall patterns, mean temperatures, elevation, and geomorphology. The following 5 ecoregio ...
- DOI:
- 10.1093/jmedent/34.5.499
- PubMed:
- 9379453
- https://doi.org/10.1093/jmedent/34.5.499
- Author:
- Arachchi L P Vidhana
- Source:
- CORD. Coconut research & development 1998 v.14 no.02 pp. 1-9
- ISSN:
- 0215-1162
- Subject:
- Brachiaria; Cocos nucifera; Pueraria; coconuts; cover crops; defoliation; ecoregions; evapotranspiration; leaf water potential; mulches; neutrons; rain; research; soil water; Sri Lanka
- Abstract:
- ... An investigation on the ability ofdifferent types of mulches to conserve soil moisture and their effect on coconutpalm (Dwarfx Tall; CRIC 65) was carried out in Madampe soil series at Bandirripuwa Estate, Lunuwila located in agro ecological region of IL3 of Sri Lanka. Different types ofmulches compared in this study were dried coconut fronds and leaves, cover crop with Pueraria phasioloides and Br ...
- DOI:
- https://doi.org/10.37833/cord.v14i02.317
- https://doi.org/https://doi.org/10.37833/cord.v14i02.317
- Author:
- Janet Franklin
- Source:
- Journal of vegetation science 1998 v.9 no.5 pp. 733-748
- ISSN:
- 1100-9233
- Subject:
- atmospheric precipitation; bioclimatic indexes; chaparral; climate; ecoregions; forest land; geographical coordinates; geographical distribution; growing season; models; national forests; prediction; sage; shrubs; soil depth; solar radiation; spring; temperature; winter; California
- Abstract:
- ... Generalized additive, generalized linear, and classification tree models were developed to predict the distribution of 20 species of chaparral and coastal sage shrubs within the southwest ecoregion of California. Mapped explanatory variables included bioclimatic attributes related to primary environmental regimes: averages of annual precipitation, minimum temperature of the coldest month, maximum ...
- DOI:
- 10.2307/3237291
- https://doi.org/10.2307/3237291
- Author:
- Sushil S Dixit; John P Smol; Donald F Charles; Robert M Hughes; Steven G Paulsen; Gary B Collins
- Source:
- Canadian journal of fisheries and aquatic sciences 1999 v.56 no.1 pp. 131-152
- ISSN:
- 1205-7533
- Subject:
- Bacillariophyceae; acid deposition; chlorides; ecoregions; environmental factors; eutrophication; highlands; lakes; lowlands; models; pH; phosphorus; plateaus; sediments; water quality; Adirondacks; New England region; Northeastern United States
- Abstract:
- ... Diatom assemblages were selected as indicators of lake condition and to assess historical lake water quality changes in 257 lakes in the northeastern United States. The "top" (surface sediments, present-day) and "bottom" (generally from >30 cm deep, representing historical conditions) samples from sediment cores collected from lakes and reservoirs were analyzed for diatom assemblages. The distribu ...
- DOI:
- 10.1139/f98-148
- https://doi.org/10.1139/f98-148
- Author:
- Nagendra, H.; Gadgil, M.
- Source:
- Proceedings of the National Academy of Sciences of the United States of America 1999 v.96 no.16 pp. 9154-9158
- ISSN:
- 0027-8424
- Subject:
- forest trees; ecoregions; botanical composition; Angiospermae; remote sensing; forests; India
- Abstract:
- ... We examine the efficacy of a scheme of multiscale assessment of biodiversity linking remote sensing on larger spatial scales with localized field sampling. A classification of ecological entities from biosphere to individual organisms in the form of a nested hierarchy is employed, such that entities at any level are differentiated in terms of their composition/configuration involving entities at t ...
- DOI:
- 10.1073/pnas.96.16.9154
- PubMed:
- 10430911
- PubMed Central:
- PMC17748
- https://doi.org/10.1073/pnas.96.16.9154
- Author:
- Naomi E. Detenbeck; Susan M. Galatowitsch; Jim Atkinson; Helen Ball
- Source:
- Wetlands 1999 v.19 no.4 pp. 789-820
- ISSN:
- 0277-5212
- Subject:
- wetlands; land use; environmental assessment; disturbed soils; ecoregions; United States; Canada
- Abstract:
- ... Wetland coverage and type distributions vary systematically by ecoregion across the Great Lakes Basin. Land use and subsequent changes in wetland type distributions also vary among ecoregions. Incidence of wetland disturbance varies significantly within ecoregions but tends to increase from north to south with intensity of land use. Although the nature of disturbance activities varies by predomina ...
- DOI:
- 10.1007/BF03161785
- https://doi.org/10.1007/BF03161785
16. Development and evaluation of predictive models for measuring the biological integrity of streams
- Author:
- Charles P. Hawkins; Richard H. Norris; James N. Hogue; Jack W. Feminella
- Source:
- Ecological applications 2000 v.10 no.5 pp. 1456-1477
- ISSN:
- 1051-0761
- Subject:
- aquatic invertebrates; ecoregions; land use; logging; models; prediction; streams; watersheds; California
- Abstract:
- ... The ratio of the number of observed taxa to that expected to occur in the absence of human‐caused stress (O/E) is an intuitive and ecologically meaningful measure of biological integrity. We examined how O/E ratios derived from stream invertebrate data varied among 234 unimpaired reference sites and 254 test sites potentially impaired by past logging. Data were collected from streams in three mont ...
- DOI:
- 10.1890/1051-0761(2000)010[1456:DAEOPM]2.0.CO;2
- https://doi.org/10.1890/1051-0761(2000)010[1456:DAEOPM]2.0.CO;2
- Author:
- McMaster D. Glen; Davis Stephen K.
- Source:
- Journal of field ornithology 2001 v.72 no.2 pp. 195-210
- ISSN:
- 0273-8570
- Subject:
- birds; community structure; cropland; ecoregions; grasslands; habitats; models; regression analysis; species diversity; surveys; wildlife; Alberta; Manitoba; Saskatchewan
- Abstract:
- ... In the early 1990s Agriculture Canada's Permanent Cover Program (PCP) converted over 445,000 ha of cropland to perennial vegetative cover. The wildlife benefits of the PCP have not been the subject of previous research. We conducted grassland bird surveys on 629 PCP sites and 564 cropland sites across Alberta, Saskatchewan, and Manitoba between 25 May and 3 July 1998. PCP sites showed higher avian ...
- DOI:
- 10.1648/0273-8570(2001)072[0195:AEOCSP]2.0.CO;2
- https://doi.org/10.1648/0273-8570(2001)072[0195:AEOCSP]2.0.CO;2
- Author:
- Matthew MacLeod; David G. Woodfine; Donald Mackay; Tom McKone; Deborah Bennett; Randy Maddalena
- Source:
- Environmental science and pollution research international 2001 v.8 no.3 pp. 156
- ISSN:
- 0944-1344
- Subject:
- basins; case studies; coastal water; databases; ecoregions; environmental fate; equations; freshwater; geographic information systems; meteorological data; models; pollutants; sediments; soil; toxaphene; vegetation; Great Lakes; Southeastern United States
- Abstract:
- ... We present the Berkeley-Trent North American contaminant fate model (BETR North America), a regionally segmented multimedia contaminant fate model based on the fugacity concept. The model is built on a framework that links contaminant fate models of individual regions, and is generally applicable to large, spatially heterogeneous areas. The North American environment is modeled as 24 ecological re ...
- DOI:
- 10.1007/BF02987379
- https://doi.org/10.1007/BF02987379
- Author:
- Charles F. Rabeni; Ning Wang
- Source:
- Environmental monitoring and assessment 2001 v.71 no.2 pp. 177-185
- ISSN:
- 0167-6369
- Subject:
- Chironomidae; biological assessment; data collection; ecoregions; macroinvertebrates; streams; Missouri
- Abstract:
- ... We compared the sensitivity of commonly usedbioassessment metrics to detect organic impairment ofstreams using data sets that varied only in the inclusion orexclusion of Chironomidae identified to genus. We evaluatedsituations in two contrasting ecoregions of Missouri, U.S.A.,the Ozark ecoregion and the Prairie ecoregion whereChironomidae comprise an average of 32 and 42%,respectively, of the tota ...
- DOI:
- 10.1023/A:1017523115381
- https://doi.org/10.1023/A:1017523115381
- Author:
- Erica Fleishman; Robert B. Blair; Dennis D. Murphy
- Source:
- Ecological applications 2001 v.11 no.5 pp. 1489-1501
- ISSN:
- 1051-0761
- Subject:
- conservation areas; ecoregions; indicator species; sampling; taxonomy
- Abstract:
- ... Empirical validation that putative umbrella species protect many co‐occurring species is rare. Using 10 sets of data, representing two taxonomic groups and three ecoregions, we tested the effectiveness of a recently developed index for selection of umbrella species. We also tested whether species identified with the index were more effective umbrellas than species selected at random, evaluated whe ...
- DOI:
- 10.1890/1051-0761(2001)011[1489:EVOAMF]2.0.CO;2
- https://doi.org/10.1890/1051-0761(2001)011[1489:EVOAMF]2.0.CO;2