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1. A Novel Method for Testing Automatic Boom Height Control Systems for Field Sprayers

Author:
Herbst, Andreas; Osteroth, Hans-Jürgen
Source:
Gesunde Pflanzen 2019 v.71 no.Supplement 1 pp. 17-24
ISSN:
0367-4223
Subject:
canopy,   etc   ; liquids; plant protection; sprayers;     Show all 4 Subjects
Abstract:
... Automatic boom height control systems for sprayers have become more common in recent years. These systems shall maintain a set boom height above the target area (canopy or ground) as an important factor for an accurate distribution of the spray liquid and sufficient drift control. At the Institute for Application Techniques in Plant Protection in cooperation with CheckTec a novel procedure was dev ...
DOI:
10.1007/s10343-019-00445-x

2. Canopy height recovery after selective logging in a lowland tropical rain forest

Author:
Okuda, Toshinori; Yamada, Toshiro; Hosaka, Tetsuro; Miyasaku, Naohiro; Hashim, Mazlan; Lau, Alivin Meng Shin; Saw, Leng Guan
Source:
Forest ecology and management 2019 v.442 pp. 117-123
ISSN:
0378-1127
Subject:
canopy; canopy height,   etc   ; forest reserves; lidar; logging; simulation models; tropical rain forests; Malaysia;     Show all 8 Subjects
Abstract:
... The effects of selective logging on canopy height were studied in a lowland tropical rain forest in Pasoh Forest Reserve, Peninsular Malaysia. Canopy height was measured in 2003 and 2011 by using an airborne light detection and ranging system and mapped on a 2.5-m grid over logged and primary forest plots. The logged forest plot was in an area where a selective logging operation had been conducted ...
DOI:
10.1016/j.foreco.2019.03.045

3. Boreal canopy surfaces from spaceborne stereogrammetry

Author:
Montesano, Paul M.; Neigh, Christopher S.R.; Wagner, William; Wooten, Margaret; Cook, Bruce D.
Source:
Remote sensing of environment 2019 v.225 pp. 148-159
ISSN:
0034-4257
Subject:
canopy gaps; forest canopy,   etc   ; boreal forests; lidar; models; remote sensing; snow; Alaska;     Show all 8 Subjects
Abstract:
... Surface elevation estimates from high resolution spaceborne image (HRSI) stereogrammetry are used to examine fine-scaled structure of boreal forest canopies. These data can depict detailed spatial patterns of vertical forest structure at remote sites across the circumpolar domain where these estimates would otherwise be unavailable. This work examines where these estimates are most effective at de ...
DOI:
10.1016/j.rse.2019.02.012

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. Mapping vegetation community types in a highly disturbed landscape: integrating hierarchical object-based image analysis with lidar-derived canopy height data

Author:
Snavely, Rachel A.; Uyeda, Kellie A.; Stow, Douglas A.; O’Leary, John F.; Lambert, Julie
Source:
International journal of remote sensing 2019 v.40 no.11 pp. 4384-4400
ISSN:
1366-5901
Subject:
canopy; canopy height,   etc   ; image analysis; landscapes; lidar; near infrared photography; plant communities; remote sensing; shrubs; vegetation; California;     Show all 11 Subjects
Abstract:
... Focusing on the semi-arid and highly disturbed landscape of San Clemente Island (SCI), California, we test the effectiveness of incorporating a hierarchical object-based image analysis (OBIA) approach with high-spatial resolution imagery and canopy height surfaces derived from light detection and ranging (lidar) data for mapping vegetation communities. The hierarchical approach entailed segmentati ...
DOI:
10.1080/01431161.2018.1562588

12. Modelling forest canopy gaps using LiDAR-derived variables

Author:
Lombard, Leighton; Ismail, Riyad; Poona, Nitesh
Source:
Geocarto international 2019 v.34 no.2 pp. 179-193
ISSN:
1752-0762
Subject:
canopy gaps; canopy height,   etc   ; Eucalyptus grandis; data collection; forest management; forests; image analysis; lidar; models; remote sensing;     Show all 10 Subjects
Abstract:
... Remote sensing has revolutionized forest management and has been widely employed to model canopy gaps. In this study, a canopy height model (CHM) and an intensity raster (IR) derived from light detection and ranging (LiDAR) data were used to model canopy gaps within a four-year-old Eucalyptus grandis forest using an object-based image analysis (OBIA) approach. Model thematic accuracies using the C ...
DOI:
10.1080/10106049.2017.1377775

13. Canopy penetration depth estimation with TanDEM-X and its compensation in temperate forests

Author:
Schlund, Michael; Baron, Daniel; Magdon, Paul; Erasmi, Stefan
Source:
ISPRS journal of photogrammetry and remote sensing 2019 v.147 pp. 232-241
ISSN:
0924-2716
Subject:
canopy; canopy height,   etc   ; deforestation; forest growth; geometry; image analysis; lidar; models; monitoring; synthetic aperture radar; temperate forests;     Show all 11 Subjects
Abstract:
... The potential of X-band interferometric synthetic aperture radar (InSAR) heights (e.g. from the TanDEM-X mission) for vegetation canopy height estimation has long been recognized. However, the penetration of the X-band into the canopy results in a height bias and substantially affects this estimation. The aim of the study was to apply a physical model to compensate the penetration depth (i.e. heig ...
DOI:
10.1016/j.isprsjprs.2018.11.021

14. 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

15. 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

16. A novel framework to detect conventional tillage and no-tillage cropping system effect on cotton growth and development using multi-temporal UAS data

Author:
Ashapure, Akash; Jung, Jinha; Yeom, Junho; Chang, Anjin; Maeda, Murilo; Maeda, Andrea; Landivar, Juan
Source:
ISPRS journal of photogrammetry and remote sensing 2019 v.152 pp. 49-64
ISSN:
0924-2716
Subject:
canopy; canopy height,   etc   ; biomass; confidence interval; conventional tillage; cotton; cropping systems; growing season; growth and development; no-tillage; normalized difference vegetation index; precision agriculture;     Show all 12 Subjects
Abstract:
... Recent years have witnessed enormous interest in the application of Unmanned Aerial Systems (UAS) for precision agriculture. This study presents a novel approach to use multi-temporal UAS data for comparison of two management practices in cotton, conventional tillage (CT) and no-tillage (NT). The plant parameters considered for the comparison are: canopy height (CH), canopy cover (CC), canopy volu ...
DOI:
10.1016/j.isprsjprs.2019.04.003

17. Vegetation Index Weighted Canopy Volume Model (CVMVI) for soybean biomass estimation from Unmanned Aerial System-based RGB imagery

Author:
Maimaitijiang, Maitiniyazi; Sagan, Vasit; Sidike, Paheding; Maimaitiyiming, Matthew; Hartling, Sean; Peterson, Kyle T.; Maw, Michael J.W.; Shakoor, Nadia; Mockler, Todd; Fritschi, Felix B.
Source:
ISPRS journal of photogrammetry and remote sensing 2019 v.151 pp. 27-41
ISSN:
0924-2716
Subject:
canopy; canopy height,   etc   ; Glycine max; aboveground biomass; agroecology; basal area; data collection; genotype; growing season; least squares; models; phenotype; photogrammetry; precision agriculture; prediction; soybeans; vegetation index; Missouri;     Show all 18 Subjects
Abstract:
... Crop biomass estimation with high accuracy at low-cost is valuable for precision agriculture and high-throughput phenotyping. Recent technological advances in Unmanned Aerial Systems (UAS) significantly facilitate data acquisition at low-cost along with high spatial, spectral, and temporal resolution. The objective of this study was to explore the potential of UAS RGB imagery-derived spectral, str ...
DOI:
10.1016/j.isprsjprs.2019.03.003

18. 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

19. Object-based forest gaps classification using airborne LiDAR data

Author:
Mao, Xuegang; Hou, Jiyu
Source:
Journal of forestry research 2019 v.30 no.2 pp. 617-627
ISSN:
1007-662X
Subject:
canopy gaps; canopy height,   etc   ; data collection; decision support systems; equations; lidar; models; secondary forests; spatial data; support vector machines; topography; trees; China;     Show all 13 Subjects
Abstract:
... Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data. To study the segmentation and classification processes of object-based forest gaps classification at a regional scale, we sampled a natural secondary forest in northeast China at Maoershan Experimental Forest Farm. Airborne light detection and ranging (LiDAR; 3.7 points/m²) da ...
DOI:
10.1007/s11676-018-0652-3

20. 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