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1. Spatial distribution and growth association of regeneration in gaps of Chinese pine (Pinus tabuliformis Carr.) plantation in northern China

Author:
Wang, Zhibin; Yang, Haijiao; Wang, Dihai; Zhao, Zhong
Source:
Forest ecology and management 2019 v.432 pp. 387-399
ISSN:
0378-1127
Subject:
canopy; canopy height,   etc   ; Pinus tabuliformis; afforestation; autocorrelation; clearcutting; monitoring; natural regeneration; plantations; soil; trees; vegetation; China;     Show all 13 Subjects
Abstract:
... Chinese pine is one of the major afforestation species in North China, and plantations of this species are of great significance for improving the ecological environment and for conserving soil and water. However, most of the Chinese pine plantations established by the government in the 1970s are mature or nearly mature. Therefore, how to successfully promote natural regeneration has become a majo ...
DOI:
10.1016/j.foreco.2018.09.032

2. The impact of ancient tree form on modern landscape preferences

Author:
Townsend, Joseph B.; Barton, Susan
Source:
Urban forestry & urban greening 2018 v.34 pp. 205-216
ISSN:
1618-8667
Subject:
canopy,   etc   ; emotions; landscapes; trees;     Show all 4 Subjects
Abstract:
... Empirical studies of the relationship between aspects of the landscape and human emotions have been fruitful over the last few decades. In fact, we are awash in data that describes a correlation between natural landscapes and positive human feelings. While this plethora of data has been useful to various disciplines, it has not lead to an explanatory theory as to why and how the landscape should h ...
DOI:
10.1016/j.ufug.2018.06.004

3. An Exponential Model of Urban Geometry for Use in Radiative Transfer Applications

Author:
Hogan, Robin J.
Source:
Boundary-layer meteorology 2019 v.170 no.3 pp. 357-372
ISSN:
0006-8314
Subject:
canopy,   etc   ; geometry; models; probability distribution; radiative transfer; urban areas;     Show all 6 Subjects
Abstract:
... In radiative transfer schemes for urban areas it is common to approximate urban geometry by infinitely long streets of constant width, or other very idealized forms. For solar and thermal-infrared radiative transfer applications, we argue that horizontal urban geometry is described uniquely by the probability distribution of wall-to-wall separation distances. The analysis of building layout from c ...
DOI:
10.1007/s10546-018-0409-8

4. No resonant response of Scots pine trees to wind excitation

Author:
Schindler, Dirk; Mohr, Manuel
Source:
Agricultural and forest meteorology 2019 v.265 pp. 227-244
ISSN:
0168-1923
Subject:
canopy,   etc   ; Pinus sylvestris; air flow; energy; roots; trees; wavelet; wind;     Show all 8 Subjects
Abstract:
... The response of four Scots pine trees to wind excitation was measured and analyzed. We investigated whether wind-induced tree sway in the fundamental mode is affected and enhanced by resonance effects between cyclic wind loading and oscillatory tree response. By combining results from wavelet analysis and analysis of phase-amplitude coupling, we demonstrate that the response in the fundamental mod ...
DOI:
10.1016/j.agrformet.2018.11.021

5. Review of indirect optical measurements of leaf area index: Recent advances, challenges, and perspectives

Author:
Yan, Guangjian; Hu, Ronghai; Luo, Jinghui; Weiss, Marie; Jiang, Hailan; Mu, Xihan; Xie, Donghui; Zhang, Wuming
Source:
Agricultural and forest meteorology 2019 v.265 pp. 390-411
ISSN:
0168-1923
Subject:
canopy,   etc   ; forestry; leaf angle; leaf area index; leaves;     Show all 5 Subjects
Abstract:
... Leaf area index (LAI) is a key parameter of vegetation structure in the fields of agriculture, forestry, and ecology. Optical indirect methods based on the Beer-Lambert law are widely adopted in numerous fields given their high efficiency and feasibility for LAI estimation. These methods have undergone considerable progress in the past decades, thereby making them operational in ground-based LAI m ...
DOI:
10.1016/j.agrformet.2018.11.033

6. Spatial correlation of pit and mound topography with canopy gaps in a virgin mixed beech forest, northern Iran

Author:
Habashi, Hashem
Source:
Journal of forestry research 2019 v.30 no.1 pp. 295-303
ISSN:
1007-662X
Subject:
canopy gaps,   etc   ; Fagus; dead wood; forests; statistics; topography; trees; Iran;     Show all 8 Subjects
Abstract:
... In a reserved forest parcel in a virgin eastern Hyrcanian mixed beech forest, 80 ha was surveyed to determine the pit and mound topography, canopy gaps and dead trees. The aim was to investigate the spatial patterns and correlation of pit and mound features with canopy gaps. Seventy-five canopy gaps and 61 pit and mound features were identified. The univariate first order nearest neighbor (RCE) an ...
DOI:
10.1007/s11676-018-0604-y

7. The Atmospheric Boundary Layer Over Urban-Like Terrain: Influence of the Plan Density on Roughness Sublayer Dynamics

Author:
Perret, Laurent; Basley, Jérémy; Mathis, Romain; Piquet, Thibaud
Source:
Boundary-layer meteorology 2019 v.170 no.2 pp. 205-234
ISSN:
0006-8314
Subject:
canopy,   etc   ; energy; landscapes; roughness; spectral analysis; statistics; troposphere; urban areas;     Show all 8 Subjects
Abstract:
... We investigate the effect of the packing density of cubical roughness elements on the characteristics of both the roughness sublayer and the overlying turbulent boundary layer, in the context of atmospheric flow over urban areas. This is based on detailed wind-tunnel hot-wire measurements of the streamwise velocity component with three wall-roughness configurations and two freestream flow speeds. ...
DOI:
10.1007/s10546-018-0396-9

8. A novel method for testing automatic systems for controlling the spray boom height

Author:
Herbst, Andreas; Osteroth, Hans-Jürgen; Stendel, Hartje
Source:
Biosystems engineering 2018 v.174 pp. 115-125
ISSN:
1537-5110
Subject:
canopy,   etc   ; algorithms; sprayers; statistical analysis;     Show all 4 Subjects
Abstract:
... Automatic boom height control (BHC) systems for sprayers have become more common in recent years. The accuracy of the BHC is dependent on the quality of the height measurement as well as on the control algorithm that should be tailored to the dynamic behaviour of the spray boom and its suspension. There is a need for evaluating BHC performance but there is no objective test method available. A pro ...
DOI:
10.1016/j.biosystemseng.2018.06.003

9. Dispersion of a Passive Scalar Within and Above an Urban Street Network

Author:
Goulart, E.V.; Coceal, O.; Belcher, S.E.
Source:
Boundary-layer meteorology 2018 v.166 no.3 pp. 351-366
ISSN:
0006-8314
Subject:
canopy,   etc   ; advection; mathematical models; prediction;     Show all 4 Subjects
Abstract:
... The transport of a passive scalar from a continuous point-source release in an urban street network is studied using direct numerical simulation (DNS). Dispersion through the network is characterized by evaluating horizontal fluxes of scalar within and above the urban canopy and vertical exchange fluxes through the canopy top. The relative magnitude and balance of these fluxes are used to distingu ...
DOI:
10.1007/s10546-017-0315-5

10. The effectiveness of lidar remote sensing for monitoring forest cover attributes and landscape restoration

Author:
Almeida, D.R.A.; Stark, S.C.; Chazdon, R.; Nelson, B.W.; Cesar, R.G.; Meli, P.; Gorgens, E.B.; Duarte, M.M.; Valbuena, R.; Moreno, V.S.; Mendes, A.F.; Amazonas, N.; Gonçalves, N.B.; Silva, C.A.; Schietti, J.; Brancalion, P.H.S.
Source:
Forest ecology and management 2019 v.438 pp. 34-43
ISSN:
0378-1127
Subject:
canopy height; forest canopy,   etc   ; biomass; compliance; forest restoration; land degradation; landscape management; landscapes; leaf area; lidar; monitoring; remote sensing; scanners; secondary forests; species richness; trees; Brazil;     Show all 17 Subjects
Abstract:
... Ambitious pledges to restore over 400 million hectares of degraded lands by 2030 have been made by several countries within the Global Partnership for Forest Landscape Restoration (FLR). Monitoring restoration outcomes at this scale requires cost-effective methods to quantify not only forest cover, but also forest structure and the diversity of useful species. Here we obtain and analyze structural ...
DOI:
10.1016/j.foreco.2019.02.002

11. Proximity to canopy mediates changes in the defensive chemistry and herbivore loads of an understory tropical shrub, Piper kelleyi

Author:
Glassmire, Andrea E.; Philbin, Casey; Richards, Lora A.; Jeffrey, Christopher S.; Snook, Joshua S.; Dyer, Lee A.
Source:
Ecology letters 2019 v.22 no.2 pp. 332-341
ISSN:
1461-023X
Subject:
canopy; canopy height,   etc   ; Piper; biochemical pathways; chemical constituents of plants; chemical defenses; chemical ecology; field experimentation; forests; herbivores; landscapes; metabolites; shrubs; transmittance; understory;     Show all 15 Subjects
Abstract:
... Phytochemical traits are a key component of plant defense theory. Chemical ecology has been biased towards studying effects of individual metabolites even though effective plant defenses are comprised of diverse mixtures of metabolites. We tested the phytochemical landscape hypothesis, positing that trophic interactions are contingent upon their spatial location across a phytochemically diverse la ...
DOI:
10.1111/ele.13194

12. Variation of leaf angle distribution quantified by terrestrial LiDAR in natural European beech forest

Author:
Liu, Jing; Skidmore, Andrew K.; Wang, Tiejun; Zhu, Xi; Premier, Joe; Heurich, Marco; Beudert, Burkhard; Jones, Simon
Source:
ISPRS journal of photogrammetry and remote sensing 2019 v.148 pp. 208-220
ISSN:
0924-2716
Subject:
canopy; canopy height,   etc   ; Fagus sylvatica subsp. sylvatica; carbon; data collection; forests; leaf angle; leaf area index; leaves; lidar; models; photosynthesis; statistical analysis;     Show all 13 Subjects
Abstract:
... Leaf inclination angle and leaf angle distribution (LAD) are important plant structural traits, influencing the flux of radiation, carbon and water. Although leaf angle distribution may vary spatially and temporally, its variation is often neglected in ecological models, due to difficulty in quantification.In this study, terrestrial LiDAR (TLS) was used to quantify the LAD variation in natural Eur ...
DOI:
10.1016/j.isprsjprs.2019.01.005

13. Different representations of canopy structure—A large source of uncertainty in global land surface modeling

Author:
Dai, Yongjiu; Yuan, Hua; Xin, Qinchuan; Wang, Dagang; Shangguan, Wei; Zhang, Shupeng; Liu, Shaofeng; Wei, Nan
Source:
Agricultural and forest meteorology 2019 v.269-270 pp. 119-135
ISSN:
0168-1923
Subject:
canopy,   etc   ; absorption; botanical composition; ecosystems; geometry; land cover; models; shortwave radiation; uncertainty; vegetation cover;     Show all 10 Subjects
Abstract:
... Land surface models generally use a “mosaic” approach to represent subgrid variation in canopy structure within a given land cell in two ways: one is based on vegetation cover types (VCT) (e.g., biomes or land cover classes); the other uses plant functional types (PFT)—a further breakdown of VCTs. The two representations largely differ in their representations of vegetation composition and canopy ...
DOI:
10.1016/j.agrformet.2019.02.006

14. Real-Time Monitoring of Spray Drift from Three Different Orchard Sprayers

Author:
Blanco, Magali N.; Fenske, Richard A.; Kasner, Edward J.; Yost, Michael G.; Seto, Edmund; Austin, Elena
Source:
Chemosphere 2019 v.222 pp. 46-55
ISSN:
0045-6535
Subject:
canopy,   etc   ; air; confidence interval; farms; geometry; monitoring; orchards; particulates; pesticides; sprayers; wind speed; Washington (state);     Show all 12 Subjects
Abstract:
... In Washington State, half of all pesticide-related illnesses in agriculture result from drift, the off-target movement of pesticides. Of these, a significant proportion involve workers on another farm and orchard airblast applications. We compared the spray drift exposure reduction potential of two modern tower sprayers – directed air tower (DAT) and multi-headed fan tower (MFT), in relation to a ...
DOI:
10.1016/j.chemosphere.2019.01.092

15. Quantifying 3D structure and occlusion in dense tropical and temperate forests using close-range LiDAR

Author:
Schneider, Fabian D.; Kükenbrink, Daniel; Schaepman, Michael E.; Schimel, David S.; Morsdorf, Felix
Source:
Agricultural and forest meteorology 2019 v.268 pp. 249-257
ISSN:
0168-1923
Subject:
forest canopy,   etc   ; algorithms; branches; leaves; lidar; micrometeorology; models; temperate forests; understory; unmanned aerial vehicles;     Show all 10 Subjects
Abstract:
... Terrestrial laser scanning (TLS) has emerged as a reference for three-dimensional measurements of forest structure as well as forest reconstruction and modeling. Ground-based measurements can be complemented by new light-weight sensors on unmanned aerial vehicles (UAVs) or laser scans from canopy cranes or towers. However, it is still largely unknown how much of the forest canopy volume can be sam ...
DOI:
10.1016/j.agrformet.2019.01.033

16. Ephemeral temporal partitioning may facilitate coexistence in competing species

Author:
Sovie, Adia R.; Greene, Daniel U.; Frock, Catherine F.; Potash, Alex D.; McCleery, Robert A.
Source:
Animal behaviour 2019 v.150 pp. 87-96
ISSN:
0003-3472
Subject:
canopy,   etc   ; Sciurus carolinensis; Sciurus niger; allopatry; animal behavior; cameras; food availability; seeds; squirrels; sympatry; Florida;     Show all 11 Subjects
Abstract:
... Animals change their daily activity patterns in response to season, food availability and the presence of competitors. Competition may be an important driver of a species’ daily activity pattern, as animals manage conflict by avoiding each other temporally. We evaluated how vegetation structure and the presence of competitors changed the daily activity patterns of closely related fox squirrels, Sc ...
DOI:
10.1016/j.anbehav.2019.01.020

17. Neottia cordata (Orchidaceae) at its southernmost distribution border in Europe: Threat status and effectiveness of Natura 2000 Network for its conservation

Author:
Tsiftsis, Spyros; Djordjević, Vladan; Tsiripidis, Ioannis
Source:
Journal for nature conservation 2019 v.48 pp. 27-35
ISSN:
1617-1381
Subject:
canopy,   etc   ; Neottia; Picea abies; Pinus sylvestris; forests; habitats; models; trees; Greece;     Show all 9 Subjects
Abstract:
... Neottia cordata is an orchid species that exclusively occurs in Picea abies subsp. abies and Pinus sylvestris stands and forms its southernmost distribution limits in Greece. Over the last decade, it has been recorded in numerous sites, in which it forms small colonies, both in terms of population and area. This research re-evaluates the threat status of Neottia cordata based on updated chorologic ...
DOI:
10.1016/j.jnc.2019.01.006

18. Green firebreaks as a management tool for wildfires: Lessons from China

Author:
Cui, Xinglei; Alam, Md Azharul; Perry, George LW.; Paterson, Adrian M.; Wyse, Sarah V.; Curran, Timothy J.
Source:
Journal of environmental management 2019 v.233 pp. 329-336
ISSN:
0301-4797
Subject:
canopy,   etc   ; climate; fire break; fire suppression; guidelines; land use; landscapes; vegetation; wildfires; wildland fire management; China;     Show all 11 Subjects
Abstract:
... Wildfire is a widespread natural hazard that is expected to increase in areal extent, severity and frequency with ongoing changes in climate and land-use. One tool that has been used in an effort to reduce the damage caused by wildfires is green firebreaks: strips of low-flammability vegetation grown at strategic locations in the landscape. Green firebreaks are increasingly being recommended for w ...
DOI:
10.1016/j.jenvman.2018.12.043

19. Feasibility of a Solid set canopy delivery system for efficient agrochemical delivery in vertical shoot position trained vineyards

Author:
Sinha, Rajeev; Khot, Lav R.; Hoheisel, Gwen-Alyn; Grieshop, Matthew J.; Bahlol, Haitham
Source:
Biosystems engineering 2019 v.179 pp. 59-70
ISSN:
1537-5110
Subject:
canopy,   etc   ; Vitis; agrochemicals; air-assisted sprayers; developmental stages; humans; leaves; spray deposition; vines; vineyards;     Show all 10 Subjects
Abstract:
... Solid set canopy delivery systems (SSCDS) offer advantages such as reduced off–target drift and human exposure to chemicals compared to conventional axial–fan airblast sprayers. In this study, six different SSCDS configurations (C1–C6) with two different emitter types (E1 and E2) were installed in a vertical shoot position (VSP) trained grapevine and evaluated for spray deposition and coverage dur ...
DOI:
10.1016/j.biosystemseng.2018.12.011

20. Nature abhors a vacuum: Deciphering the vegetative reaction of the mango tree to pruning

Author:
Persello, Séverine; Grechi, Isabelle; Boudon, Frédéric; Normand, Frédéric
Source:
European journal of agronomy 2019 v.104 pp. 85-96
ISSN:
1161-0301
Subject:
canopy,   etc   ; Mangifera indica; biomass; evergreen trees; horticulture; leaf area; mangoes; pruning; vegetative growth;     Show all 9 Subjects
Abstract:
... Pruning is an important horticultural practice that generally promotes vegetative growth. However, the precise characterization of vegetative growth after pruning and of the factors affecting it are little known. The objective of this study was to decipher the vegetative response to pruning in a tropical evergreen species, the mango tree. Pruning was characterized by two factors: pruning intensity ...
DOI:
10.1016/j.eja.2019.01.007