TY - BOOK
T1 - Earth Observation of Vegetation Dynamics in Global Drylands
T2 - Evaluating Long-Term Optical and Microwave Datasets and Analyzing Woody Vegetation Trends
AU - Tian, Feng
PY - 2016
Y1 - 2016
N2 - Land degradation in global drylands has been a concern related to both the local livelihoods and the changes in terrestrial biosphere, especially in the context of substantial global environmental changes. Earth Observation (EO) provides a unique way to assess the vegetation dynamics over the past decades, which are keys to understanding the changes in global drylands. However, there are still large uncertainties and unknowns in the quality and capabilities of remote sensing data. This thesis contributes to an improved EO based assessment of dryland vegetation dynamics by 1) evaluating and exploring the widely used long-term datasets and 2) mapping trends in woody vegetation.
A highlight of the thesis is the mapping of trends in the non-green woody vegetation component in global tropical drylands, which is obtained for the first time from combing satellite optical and passive microwave observations. Trends in the woody component are found to be significant (p < 0.05) in 35% of the areas characterized by a non-significant trend in the leaf component, indicating a pronounced gradual growth/decline in woody vegetation not captured by traditional assessments. The thesis also reveals contrasting trends in the woody cover between humid areas and drylands in Africa, which are explained by human activities and climate changes, respectively.
AB - Land degradation in global drylands has been a concern related to both the local livelihoods and the changes in terrestrial biosphere, especially in the context of substantial global environmental changes. Earth Observation (EO) provides a unique way to assess the vegetation dynamics over the past decades, which are keys to understanding the changes in global drylands. However, there are still large uncertainties and unknowns in the quality and capabilities of remote sensing data. This thesis contributes to an improved EO based assessment of dryland vegetation dynamics by 1) evaluating and exploring the widely used long-term datasets and 2) mapping trends in woody vegetation.
A highlight of the thesis is the mapping of trends in the non-green woody vegetation component in global tropical drylands, which is obtained for the first time from combing satellite optical and passive microwave observations. Trends in the woody component are found to be significant (p < 0.05) in 35% of the areas characterized by a non-significant trend in the leaf component, indicating a pronounced gradual growth/decline in woody vegetation not captured by traditional assessments. The thesis also reveals contrasting trends in the woody cover between humid areas and drylands in Africa, which are explained by human activities and climate changes, respectively.
UR - https://soeg.kb.dk/permalink/45KBDK_KGL/fbp0ps/alma99122559513105763
M3 - Ph.D. thesis
BT - Earth Observation of Vegetation Dynamics in Global Drylands
PB - Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen
ER -
