The Experts below are selected from a list of 11058 Experts worldwide ranked by ideXlab platform
W J Ripple - One of the best experts on this subject based on the ideXlab platform.
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assessing wildfire effects with Landsat Thematic Mapper data
International Journal of Remote Sensing, 1998Co-Authors: J D Kushla, W J RippleAbstract:We evaluated Landsat Thematic Mapper (TM) imagery to map forest survival after a wildfire using single-date and multi-date TM imagery. In addition, landscape patterns were measured to describe the wildfire effects on successional stage patterns, and their impacts on wildlife habitat. The study site was the 1991 Warner Creek Burn, covering 3669 ha, on the Willamette National Forest in western Oregon, USA. Regressions of TM band transformations were used to estimate forest survival. Single-date TM 4/5 accounted for 73% (P 0.0001) of the variation in post-burn canopy cover, whereas the TM difference (by ratio) imagery with stratification by pre-fire tasseled cap (TC) wetness explained 78% (P 0.0001). Verification of the best models using additional data in observed versus predicted post-burn canopy cover confirmed these results. The pre-fire landscape had a matrix of closed mature/old-growth stands comprising 77% of the area. After the burn, the early seral/rock stage expanded, the open mature/old-growth sta...
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analysis of conifer forest regeneration using Landsat Thematic Mapper data
Geographic Information Analysis: An Ecological Approach for the Management of Wildlife on theForest Landscape, 1995Co-Authors: Maria Fiorella, W J RippleAbstract:Landsat Thematic Mapper (TM) data were used to evaluate young conifer stands in the western Cascade Mountains of Oregon. Regression and correlation analyses were used to describe the relationships between TM band values and age of young Douglas-fir stands (2 to 35 years old). Spectral data from well regenerated Douglas-fir stands were compared to those of poorly regenerated conifer stands. TM bands 1, 2, 3, 5, 6, and 7 were inversely correlated with the age (r greater than or equal to -0.80) of well regenerated Douglas-fir stands. Overall, the 'structural index' (TM 4/5 ratio) had the highest correlation to age of Douglas-fir stands (r = 0.96). Poorly regenerated stands were spectrally distinct from well regenerated Douglas-fir stands after the stands reached an age of approximately 15 years.
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a preliminary comparison of Landsat Thematic Mapper and spot 1 hrv multispectral data for estimating coniferous forest volume
Geographic Information Analysis: An Ecological Approach for the Management of Wildlife on theForest Landscape, 1994Co-Authors: W J Ripple, S Wang, Dennis L Isaacson, D P PaineAbstract:Digital Landsat Thematic Mapper (TM) and Satellite Probatoire d'Observation de la Terre (SPOT) High Resolution Visible (HRV) images of coniferous forest canopies were compared in their relationship to forest wood volume using correlation and regression analyses. Significant inverse relationships were found between softwood volume and the spectral bands from both sensors (P less than 0.01). The highest correlations were between the log of softwood volume and the near-infrared bands (HRV band 3, r = -0.89; TM band 4, r = -0.83).
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analysis of conifer forest regeneration using Landsat Thematic Mapper data
Photogrammetric Engineering and Remote Sensing, 1993Co-Authors: Maria Fiorella, W J RippleAbstract:Landsat Thematic Mapper (TM) data were used to evaluate young conifer stands in the western Cascade Mountains of Oregon. Regression and correlation analyses were used to describe the relationships between TM band values and age of young Douglas-fir stands (2 to 35 years old). Spectral data from well regenerated Douglas-fir stands were compared to those of poorly regenerated conifer stands. TM bands 1, 2, 3, 5, 6, and 7 were inversely correlated with the age (r >_ -0.80) of well regenerated Douglas-fir stands. Overall, the "structural index" (TM 4/5 ratio) had the highest correlation to age of Douglas-fir stands (r = 0.96). Poorly regenerated stands were spectrally distinct from well regenerated Douglas-fir stands after the stands reached an age of approximately 15 years.
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a preliminary comparison of Landsat Thematic Mapper and spot 1 hrv multispectral data for estimating coniferous forest volume
International Journal of Remote Sensing, 1991Co-Authors: W J Ripple, S Wang, Dennis L Isaacson, D P PaineAbstract:Digital Landsat Thematic Mapper (TM) and SPOT high-resolution visible (HRV) images of coniferous forest canopies were compared in their relationship to forest wood volume using correlation and regression analyses. Significant inverse relationships were found between softwood volume and the spectral bands from both sensors (P less than 0.01). The highest correlations were between the log of softwood volume and the near-infrared bands.
Alireza Hajian - One of the best experts on this subject based on the ideXlab platform.
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change detection through four techniques using multi temporal Landsat Thematic Mapper data a case study on falavarjan area isfahan iran
Journal of Environmental Informatics, 2014Co-Authors: Maliheh Madanian, Alireza Soffianian, Alireza HajianAbstract:The present study was aimed to assess the applicability of four techniques for detecting changed and unchanged areas in terms of land cover in Falavarjan area, (Isfahan, Iran). The images of the multi-temporal Landsat Thematic Mapper (TM) data acquired on 17 September, 1990 and 13 August, 2010 were used to apply land cover change analysis. The Images were respectively radiometrically and geometrically corrected. The root mean square errors were less than 0.5 pixels for each image. Finally, the image differencing method was used to produce the change image. To separate out the changed and unchanged areas in the difference image, four techniques including Metternicht's method, statistical method, Liu's method and Kapur's method were employed. Among them, the Metternicht's method followed by statistical thresholding technique yielded more accurate binary images.
Maliheh Madanian - One of the best experts on this subject based on the ideXlab platform.
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change detection through four techniques using multi temporal Landsat Thematic Mapper data a case study on falavarjan area isfahan iran
Journal of Environmental Informatics, 2014Co-Authors: Maliheh Madanian, Alireza Soffianian, Alireza HajianAbstract:The present study was aimed to assess the applicability of four techniques for detecting changed and unchanged areas in terms of land cover in Falavarjan area, (Isfahan, Iran). The images of the multi-temporal Landsat Thematic Mapper (TM) data acquired on 17 September, 1990 and 13 August, 2010 were used to apply land cover change analysis. The Images were respectively radiometrically and geometrically corrected. The root mean square errors were less than 0.5 pixels for each image. Finally, the image differencing method was used to produce the change image. To separate out the changed and unchanged areas in the difference image, four techniques including Metternicht's method, statistical method, Liu's method and Kapur's method were employed. Among them, the Metternicht's method followed by statistical thresholding technique yielded more accurate binary images.
D P Paine - One of the best experts on this subject based on the ideXlab platform.
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a preliminary comparison of Landsat Thematic Mapper and spot 1 hrv multispectral data for estimating coniferous forest volume
Geographic Information Analysis: An Ecological Approach for the Management of Wildlife on theForest Landscape, 1994Co-Authors: W J Ripple, S Wang, Dennis L Isaacson, D P PaineAbstract:Digital Landsat Thematic Mapper (TM) and Satellite Probatoire d'Observation de la Terre (SPOT) High Resolution Visible (HRV) images of coniferous forest canopies were compared in their relationship to forest wood volume using correlation and regression analyses. Significant inverse relationships were found between softwood volume and the spectral bands from both sensors (P less than 0.01). The highest correlations were between the log of softwood volume and the near-infrared bands (HRV band 3, r = -0.89; TM band 4, r = -0.83).
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a preliminary comparison of Landsat Thematic Mapper and spot 1 hrv multispectral data for estimating coniferous forest volume
International Journal of Remote Sensing, 1991Co-Authors: W J Ripple, S Wang, Dennis L Isaacson, D P PaineAbstract:Digital Landsat Thematic Mapper (TM) and SPOT high-resolution visible (HRV) images of coniferous forest canopies were compared in their relationship to forest wood volume using correlation and regression analyses. Significant inverse relationships were found between softwood volume and the spectral bands from both sensors (P less than 0.01). The highest correlations were between the log of softwood volume and the near-infrared bands.
Peng Gong - One of the best experts on this subject based on the ideXlab platform.
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land cover mapping and data availability in critical terrestrial ecoregions a global perspective with Landsat Thematic Mapper and enhanced Thematic Mapper plus data
Biological Conservation, 2015Co-Authors: Peng Gong, Yichuan ShiAbstract:Abstract Land cover provides objective and multi scale information on the extent and conditions of habitats both currently and retrospectively. Over four decades since the launch of the first land-observation satellite – Landsat-1 in 1972, a tremendous number of earth observation images have been acquired and archived. Here we examined land cover mapping in 142 critical terrestrial ecoregions (identified by WWF Global 200) from three aspects: Landsat Thematic Mapper and Enhanced Thematic Mapper Plus (TM/ETM+) data availability, literature and existing global land cover map. We found that: (1) the availability of Landsat TM/ETM+ for historical land-cover change analysis in those ecoregions is poor. Only 17 ecoregions and 38 ecoregions have sufficient number of seasonal images in the Landsat archive for change analysis at 10-year and 5-year intervals, respectively. (2) Only 26 of 142 ecoregions belong to research hotspots of land cover mapping based on a spatialized literature database. (3) From a 30 m global land cover map (which is FROM-GLC, Finer Resolution Observation and Monitoring – Global Land Cover), only 28 ecoregions have greater than 80% map accuracy while 36 ecoregions have poorer than 50% map accuracy. Our finding suggests a significant gap of observation and understanding of these critical ecoregions from space, and an urgent need to meet the requirement of the conservation science community, in order for land cover data to fulfil its potential to timely monitor the loss of biodiversity from space, improve our knowledge of the state of conservation, and inform better decision making.
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Comparison of classification algorithms and training sample sizes in urban land classification with Landsat Thematic Mapper imagery
Remote Sensing, 2014Co-Authors: Congcong Li, Luanyun Hu, Jie Wang, Lei Wang, Peng GongAbstract:Although a large number of new image classification algorithms have been developed, they are rarely tested with the same classification task. In this research, with the same Landsat Thematic Mapper (TM) data set and the same classification scheme over Guangzhou City, China, we tested two unsupervised and 13 supervised classification algorithms, including a number of machine learning algorithms that became popular in remote sensing during the past 20 years. Our analysis focused primarily on the spectral information provided by the TM data. We assessed all algorithms in a per-pixel classification decision experiment and all supervised algorithms in a segment-based experiment. We found that when sufficiently representative training samples were used, most algorithms performed reasonably well. Lack of training samples led to greater classification accuracy discrepancies than classification algorithms themselves. Some algorithms were more tolerable to insufficient (less representative) training samples than others. Many algorithms improved the overall accuracy marginally with per-segment decision making.
