South and Southeast Asia (SSEA) region has experienced unprecedented land cover and land use change (LCLUC) in the past few decades and is likely to undergo further rapid development in the coming years. A great deal of concern has been raised regarding to what extent such rapid changes in LCLUC have affected major biogeochemical cycles and climate change, which are essential to ecosystem sustainability in this region. Due to these concerns, there has been a concomitant rapid expansion in the availability of data and research studies related to LCLUC for the SSEA. While a great amount of research has focused on individual LCLUC-related efforts in ground-based measurements, remotely-sensed observations, land change processes, and modeling assessment of LCLUC impacts on terrestrial biogeochemical cycles, a little effort has been made to systematically synthesize these efforts, despite the fact that different LCLUC- related efforts are interconnected. The overall goal of this proposed research is to synthesize existing research efforts on LCLUC to detect and quantify LCLUC and their impacts on biogeochemical cycles in SSEA region over the past 32 years (1981-2012). The specific objectives include: (1) Understanding the major land cover and land use (LCLU) transition activities in the study region. This will be achieved by synthesizing existing studies and the remote sensing data sets for LCLUC. (2) Advancing our understanding of the causes of land cover and land use change. In order to achieve this objective we propose to hold one workshop to systematically examine the causes of land cover change for different types of changes. The workshop will be used as the basis to develop a statistical diagnostic tool of LCLUC through the use of information of LCLUC that we developed in objective 1 and the measured biophysical, socio-economic and technological drivers of LCLUCs. (3) Improving our understanding of the historical effects of land cover change dynamics on the quantities and pathways of terrestrial carbon and nitrogen fluxes. This objective will be achieved by systematically synthesizing existing terrestrial ecosystem model results for LCLUC CO2 emissions. A second workshop will be held to develop a strategy to understand and reduce uncertainty in the estimates of the historic land use activities and resultant C emissions. These objectives and related tasks are closely aligned with NASA’s LCLUC program. The proposed research responds to one of the two major themes of this solicited research - Synthesis of LCLUC studies In addition, we will identify and quantify the likely uncertainties caused by input LCLUC and its driver data sets and model structure and assumptions. This research will be conducted in a fully collaborative manner with interdisciplinary research team members from the US and from the study region, who are experts in remote sensing of LCLUC, social-economic analysis of LCLUC and the terrestrial ecosystem model calculations of LCLUC CO2 emissions.