Assessing land use and ecosystem carbon stock from space - from a case study in slash/burn ecosystems in Laos -

In the tropical mountain of Southeast Asia, slash-and-burn (S/B) agriculture is an important food production system and widely practiced in many countries. The ecosystem carbon stock in this land use is linked not only to the carbon exchange with the atmosphere but also to the food and resource security. In this study, we revealed the land use and ecosystem carbon stock in the northern part of Laos at a regional scale based on the synergy of satellite remote sensing and in situ measurements. Chronosequential change of S/B land use and community age of fallow vegetation were derived successfully from the time-series satellite imagery, and combined with simple carbon models to assess the ecosystem carbon stock. Results suggested the carbonsequestration potential of ecosystems is strongly affected by land-use and ecosystem management scenarios. Alternative land use and ecosystem management scenarios with higher carbon stock and productivity were also proposed. These quantitative estimates would be useful to better understand and manage the land use and ecosystem carbon stock in the slash-and-burn regions of tropical mountains in Southeast Asia. This case study clearly shows that the use of geoinformation technology (remote sensing, GIS and modeling) is crucial for a wide range of agro-environmental issues. Timely, regional, and systematic monitoring is essential for "agro-ecosystems intelligence", i.e., to analyze, understand, and predict the dynamics of agro-ecosystem resources, and to assist the strategies for both domestic and international food and environmental security. It is necessary to foster an international collaboration scheme for agro-ecosystems intelligence based on satellite sensor networks.