Mapping tree species composition in South African savannas using an integrated airborne spectral and LiDAR system

被引:179
作者
Cho, Moses Azong [1 ]
Mathieu, Renaud [1 ]
Asner, Gregory P. [2 ]
Naidoo, Laven [1 ]
van Aardt, Jan [3 ]
Ramoelo, Abel [1 ]
Debba, Pravesh
Wessels, Konrad [4 ,7 ]
Main, Russell [1 ]
Smit, Izak P. J. [5 ]
Erasmus, Barend [6 ]
机构
[1] CSIR, Earth Observat Grp, Nat Resources & Environm NRE, ZA-0001 Pretoria, South Africa
[2] Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
[3] RIT Ctr Imaging Sci, Digital Imaging & Remote Sensing Grp, Rochester, NY 14623 USA
[4] CSIR, Meraka Inst, African Adv Inst Informat & Commun Technol, ZA-0001 Pretoria, South Africa
[5] Sci Serv, S African Natl Pk, ZA-1350 Skukuza, South Africa
[6] Univ Witwatersrand, Sch Anim Plant & Environm Sci, Johannesburg, South Africa
[7] Univ Pretoria, Ctr Geoinformat Sci, Dept Geog Geoinformat & Meteorol, ZA-0002 Pretoria, South Africa
基金
美国安德鲁·梅隆基金会;
关键词
Carnegie Airborne Observatory; Hyperspectral remote sensing; LiDAR WorldView-2; Savanna tree species; Land use; HYPERSPECTRAL DISCRIMINATION; INVASIVE PLANTS; LAND-USE; FOREST; IMPACT; VARIABILITY; LEAF; CLASSIFICATION; IDENTIFICATION; DELINEATION;
D O I
10.1016/j.rse.2012.07.010
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Mapping savanna tree species is of broad interest for savanna ecology and rural resource inventory. We investigated the utility of (i) the Carnegie Airborne Observatory (CAO) hyperspectral data, and WorldView-2 and Quickbird multispectral spectral data and (ii) a combined spectral + tree height dataset (derived from the CAO LiDAR system) for mapping seven common savanna tree species or genera in the Sabi Sands Reserve and communal lands adjacent to Kruger National Park, South Africa. We convolved the 72 spectral bands of the CAO imagery to eight and four multispectral channels available in the WorldView-2 and Quickbird satellite sensors, respectively. A combination of the simulated WorldView-2 data and LiDAR tree height imagery was also assessed for species classification. First, the simulated WorldView-2 imagery provided a higher classification accuracy (77% +/- 3.1 (mean +/- standard deviation)) when compared to the simulated Quickbird (65% +/- 1.9) and CAO (65% +/- 1.2) data. Secondly, the combined spectral + height dataset provided a slightly higher overall classification accuracy (79% +/- 1.8) when compared to the WorldView-2 spectral only dataset. The difference was however, statistically significant (p<0.001; one-way analysis of variance for 30 bootstrapped replicates (n = 100) of the independent validation dataset). Higher classification accuracies were observed for trees with large crowns such as S. birrea, S. africana and A. nigrescens as compared to trees with small crowns. Species composition and diversity maps of trees with large crowns were consistent with established knowledge in the area. For example, the results showed higher tree diversity (number of different species per ha) in the Sabi Sands game reserve than in the communal areas. This study highlights the feasibility of remote sensing of tree species at the landscape scale in African savannas and the potential applicability of WorldView-2 sensor in mapping savanna tree species with a large crown. (c) 2012 Elsevier Inc. All rights reserved.
引用
收藏
页码:214 / 226
页数:13
相关论文
共 72 条
[1]   The role of environmental context in mapping invasive plants with hyperspectral image data [J].
Andrew, Margaret E. ;
Ustin, Susan L. .
REMOTE SENSING OF ENVIRONMENT, 2008, 112 (12) :4301-4317
[2]   Markov-random-field-based super-resolution mapping for identification of urban trees in VHR images [J].
Ardila, Juan P. ;
Tolpekin, Valentyn A. ;
Bijker, Wietske ;
Stein, Alfred .
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING, 2011, 66 (06) :762-775
[3]  
Asner G. P, 2009, LONG TERM LOSS RECOV
[4]   Carnegie Airborne Observatory: in-flight fusion of hyperspectral imaging and waveform light detection and ranging (wLiDAR) for three-dimensional studies of ecosystems [J].
Asner, Gregory P. ;
Knapp, David E. ;
Kennedy-Bowdoin, Ty ;
Jones, Matthew O. ;
Martin, Roberta E. ;
Boardman, Joseph ;
Field, Christopher B. .
JOURNAL OF APPLIED REMOTE SENSING, 2007, 1 (01)
[5]   Airborne spectranomics: mapping canopy chemical and taxonomic diversity in tropical forests [J].
Asner, Gregory P. ;
Martin, Roberta E. .
FRONTIERS IN ECOLOGY AND THE ENVIRONMENT, 2009, 7 (05) :269-276
[6]   Invasive species detection in Hawaiian rainforests using airborne imaging spectroscopy and LiDAR [J].
Asner, Gregory P. ;
Knapp, David E. ;
Kennedy-Bowdoin, Ty ;
Jones, Matthew O. ;
Martin, Roberta E. ;
Boardman, Joseph ;
Hughes, R. Flint .
REMOTE SENSING OF ENVIRONMENT, 2008, 112 (05) :1942-1955
[7]   Invasive plants transform the three-dimensional structure of rain forests [J].
Asner, Gregory P. ;
Hughes, R. Flint ;
Vitousek, Peter M. ;
Knapp, David E. ;
Kennedy-Bowdoin, Ty ;
Boardman, Joseph ;
Martin, Roberta E. ;
Eastwood, Michael ;
Green, Robert O. .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2008, 105 (11) :4519-4523
[8]   Forest canopy height and carbon estimation at Monks Wood National Nature Reserve, UK, using dual-wavelength SAR interferometry [J].
Balzter, H. ;
Rowland, C. S. ;
Saich, P. .
REMOTE SENSING OF ENVIRONMENT, 2007, 108 (03) :224-239
[9]  
Barnard E, 2010, P 21 ANN S PATT REC
[10]   FOREST GAPS AND ISOLATED SAVANNA TREES - AN APPLICATION OF PATCH DYNAMICS IN 2 ECOSYSTEMS [J].
BELSKY, AJ ;
CANHAM, CD .
BIOSCIENCE, 1994, 44 (02) :77-84