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Past years have witnessed the transformation of land use at a high frequency and a warmer and drier climate in the Eastern Tibetan Plateau region
. To fully understand the spatial-temporal variation of ecosystem services against the changing global backdrop and to provide scientific ecosystem management measures for decision-making, a study was conducted to investigate the major ecosystem services: water yield, soil conservation and crop production from 1990 to 2015 in the Eastern Tibetan Plateau region. Three scenarios—climate change only, land use change only and both land use and climate change—were included in this study to analyze the response of ES to the above-mentioned global changes. The results show that (1) the total quantity of ES reduced in all the three scenarios, the annual ES change was scenarioII < scenarioIII < scenarioI and the periodical characteristics are present in this region; (2) the ES change in spatial distribution varied with different climate change patterns and land use transfer directions; (3) the ES composition of each ecosystem varied with different driving scenarios and different responses of the forest and wetland on climate change and land use changes were observed. Moreover, the trade-off under land use change and climate change respectively was observed in this study. Based on the results, we recommend that the local government take this trade-off and climate change into account when making decisions, continue with desertification control and improve the quality of grassland as well as forests—these efforts should enable us to achieve sustainable development of human beings and the natural ecosystem
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Wang, J.; Li, H.; Hao, X.; Huang, X.; Hou, J.; Che, T.; Dai, L.; Liang, T.; Huang, C.; Li, H.; Tang, Z.; Wang, Z.
Abstract
. Snow is one of the most important components of the cryosphere. Remote sensing of snow focuses on the retrieval of snow parameters and monitoring of variations in snow using satellite data. These parameters are key inputs for hydrological and atmospheric models. Over the past 30 years, the field of snow remote sensing has grown dramatically in China. The 30-year achievements of research in different aspects of snow remote sensing in China, especially in (1) methods of retrieving snow cover, snow depth/snow water equivalent, and grain size and (2) applications to snowmelt runoff modeling, snow response on climate change, and remote sensing monitoring of snow-caused disasters are reviewed/summarized. The importance of the first remote sensing experiment on snow parameters at the upper reaches of the Heihe River Basin, in 2008, is also highlighted. A series of experiments, referred to as the Cooperative Observation Series for Snow (COSS), focus on some key topics on remote sensing of snow. COSS has been implemented for 3 years and will continue in different snow pattern regions of China. The snow assimilation system has been established in some regions using advanced ensemble Kalman filters. Finally, an outlook for the future of remote sensing of snow in China is given
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Alpine vegetation and timberline development were investigated on 4 high mountains in North China: Mt
. Taibai (34°N, 108°E; 3767 m), Mt. Guandi (38°N, 111.5°E; 2831 m), Mt. Wutai (39°N, 113.6°E; 3058 m), and Mt. Xiaowutai (40°N, 115°E; 2882 m). The relationships between distribution of tree species and climatic factors on the uppermost parts of these mountains were established. As a result of the continental climate, their timberlines are composed of larch species, such as Larix chinensis on Mt. Taibai and Larix principis-rupprechtii on the other mountains. Two climatic indices, a warmth index (WI) and a humidity index (HI), were calculated for a differentiation of tree species near the timberline. A WI of 15°C mo has been commonly regarded as the limit for the timberline in East Asia. In addition, we suggest that the Larix timberline is formed when the HI is lower than 210. The understorey species of the forest patches inside the timberline and the L chinensis forest are similar on Mt. Taibai. These species are also distributed mostly in subalpine scrubs and meadows rather than in the Abies fargesii forest. This implies greater resistance to cold and drought in L chinensis than in A fargesii. Timberline movements were roughly reconstructed through analysis of sediments from the alpine zone of Mt. Taibai. A drier climate during 1830–1450 14C years BP resulted in a lower Abies timberline and was favorable for distribution of Larix, reflected by pollen diagrams and palaeolimnological evidence, such as grain size and total organic carbon. Percentages of Abies/Picea pollen recurred from 1450 to 680 14C years BP, implying an upward movement of Abies/Picea. Abies/Picea then moved downward, and the timberline was possibly replaced by Larix. In recent centuries, Picea/Abies has tended to move upward again
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