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Aboveground net primary productivity (ANPP) and rain-use efficiency (RUE) are important indicators in assessing the response of ecosystems to climate change. In this paper, the Changtang Plateau in the Tibetan Autonomous Region was selected as the study area to analyze the spatial and temporal changes of ANPP and RUE in grassland communities and their response to climate change. The results showed the following:(1) The spatial pattern of ANPP was closely related to rainfall on the Changtang Plateau. The average ANPP over the past 15 years increased gradually from the arid west to the humid east. A consistent pattern was exhibited in different grassland types and climate zones. (2) The RUE was higher at the east and west edges of the Changtang Plateau, especially in the arid west, but was lower in the center. From the perspective of different climatic zones, the average RUE in the southern Tibetan semiarid climate zone and the Ngari arid climate zone was significantly higher than that in other climate zones. However, the average RUE in different grassland types only varied from 0.07 to 0.09 g·m−2·mm−1. The spatial variation in RUE was more distinct in different climatic zones than in different grassland types. (3) Climate change influenced the interannual variation of ANPP and RUE, but the response of ANPP to rainfall showed a significant lag. The interannual change in RUE was negatively correlated with changes in precipitation. (4) In general, a greater area showed a significant increase rather than a decrease in ANPP on the Changtang Plateau, which meant that the grassland condition is improving. The temporal variation patterns of ANPP and RUE in different climate zones were consistent with the overall patterns on the Changtang Plateau, while the variation was not significant in different grassland types. [ABSTRACT FROM AUTHOR]

A catchment is the basic unit for studying hydrologic cycle processes and associated climate change impacts. Accurate catchment delineation is essential in the field of hydrology, environment, and meteorology. Traditionally, catchment delineation is most easily carried out where the outflow area can be easily determined because of a well-defined outlet. The obstacle of the current study is to determine accurately the catchment boundary of lakes that are internally draining and, therefore, lack a well-defined outflow (i.e. inland lakes). This study describes a catchment delineation method which demarcated all the catchments of the lakes in the Qiangtang Plateau, especially for the inland lakes and their closed catchments. Lake catchment boundaries determined for the Qiangtang Plateau provide a significant advancement for water resource and climate change evaluation and agriculture production in the area. Design Type(s) modeling and simulation objective • data transformation objective • image processing objective Measurement Type(s) drainage basin Technology Type(s) computational modeling technique Factor Type(s) Classification Sample Characteristic(s) Tibetan Plateau • lake Machine-accessible metadata file describing the reported data (ISA-Tab format) [ABSTRACT FROM AUTHOR]