Results 251 to 260 of about 31,615 (293)

Retrieving forest canopy clumping index using terrestrial laser scanning data

Remote Sensing of Environment, 2018
Abstract Quantitatively characterizing the non-random spatial distributions of foliage elements including coniferous needles is critical to map the radiation regime and retrieve the biophysical parameters of a given forest canopy from three-dimensional (3-D) perspective.
Lixia Ma, Guang Zheng, Xiaofei Wang, Shiming Li, Yi Lin, Weimin Ju   +5 more
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Global clumping index map derived from the MODIS BRDF product

Remote Sensing of Environment, 2012
Abstract Clumping index (CI), quantifying the level of foliage grouping within distinct canopy structures relative to a random distribution, is a key structural parameter of plant canopies and very useful in ecological and meteorological models.
Liming He, Jing M. Chen, Jan Pisek, Crystal B. Schaaf, Alan H. Strahler   +4 more
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Research on the Directional Dependence of the Sampling Scale of Canopy Clumping Index

2021 IEEE International Geoscience and Remote Sensing Symposium IGARSS, 2021
Clumping index (CI) characterizes the clumping degree of vegetation canopy foliage relative to the random distribution, which is an important vegetation structure parameter. Digital Hemispherical Photography (DHP) is widely used in ground CI measurement and one of the key steps using this method is to determine the sampling resolution.
Yidong Tong, Ziti Jiao, Lei Cui, Siyang Yin, Xiaoning Zhang, Jing Guo, Rui Xie, ZiDong Zhu, SiJie Li   +8 more
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Leaf area index estimates obtained for clumped canopies using hemispherical photography

Agricultural and Forest Meteorology, 1999
A method has been developed to improve estimates of leaf area index determined from hemispherical images of plant canopies. The approach used has been to modify existing techniques for analysis of gap fraction at a range of zenith angles. Conventional analytical techniques determine the gap fraction for a number of concentric annuli and then calculate ...
P.R van Gardingen, G.E Jackson, S Hernandez-Daumas, G Russell, L Sharp   +4 more
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Global mapping of foliage clumping index using multi-angular satellite data

Remote Sensing of Environment, 2005
Global mapping of the vegetation clumping index is attempted for the first time using multi-angular POLDER 1 data based on a methodology that has been demonstrated to be applicable to Canada’s landmass. The clumping index quantified the level of foliage grouping within distinct canopy structures, such as tree crowns, shrubs, and row crops, relative to ...
J.M. Chen, C.H. Menges, S.G. Leblanc
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Canopy clumping index (CI): A review of methods, characteristics, and applications

Agricultural and Forest Meteorology, 2021
Abstract Canopy clumping index (CI) characterizes the spatial distribution of leaves or needles within a vegetation canopy. CI is critical in determining the canopy radiation transfer, photosynthesis, and hydrological processes. This paper reviews the field measurement and remote sensing estimation methods, characteristics, and applications of CI. CI
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[Foliage clumping index of main vegetation types in Daxing'an Mountains, Northeast China].

Ying yong sheng tai xue bao = The journal of applied ecology, 2018
The foliage clumping index quantifies the cluster degree of the leaf spatial distribution under random canopy. It is of comparable importance for establishment of ecological models. MODIS BRDF model parameter products (MCD43A1 data) and land cover types (MCD12Q1 data) were used in this study to simulate the reflectivity of the hot spots and dark spots,
Ting, Huang, Wen Yi, Fan, Xue Gang, Mao, Ying, Yu   +3 more
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Modeling and validation of the angular clumping index of forest canopy

2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2017
The clumping index (CI) is an important factor for deriving forest leaf area index (LAI) at both pixel and point scale. Due to the non-uniform distribution of leaves within trees and random layout of trees under natural conditions, the CI varies with view zenith angle (VZA) as well as the gap fraction. The variation tendency of gap fraction and CI with
Jingjing Peng, Wenjie Fan, Lizhao Wang, Jvcai Li, Dingfang Tian, Xiru Xu   +5 more
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Estimation of clumping index and LAI from Terrestrial LiDAR data

2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2016
In this study, clumping index and effective leaf area index (LAI) are estimated from Terrestrial Laser Scanner (TLS) data. Integrating vertical and tilt scanning from Terrestrial laser scanner, accounting zenith angle and path length two factors, discrete directional canopy gap fraction could be calculated and effective LAI could be estimated from ...
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The relationship between vegetation clumping index angular distribution and canopy spatial pattern

2012 IEEE International Geoscience and Remote Sensing Symposium, 2012
Vegetation clumping index is required for canopy reflectance modeling and leaf area index (LAI) retrieval. Frequently used is the average clumping index. The angle effect is normalized in the definition of average clumping index. Clumping index angular distribution with different canopy spatial pattern and the same architectural features of single ...
Biao Cao, Qinhuo Liu, Yongming Du, Hua Li, Li Li   +4 more
openaire   +1 more source