Subjects: Geosciences >> Geography submitted time 2024-07-04 Cooperative journals: 《干旱区研究》
Abstract： Lakes, as integral components of terrestrial ecosystems, are vital for regional economic growth and ecological security. Previous studies have primarily focused on typical or large lakes in the Xinjiang region, with comparatively less attention given to smaller lakes. This study analyzed the areal dynamics of 74 small and medium-sized lakes in Xinjiang from 1991 to 2020, conducting a comprehensive analysis of lakes at varying altitudes and with diverse geographical characteristics. The research uncovered that during 1991-2020, the total area of lakes in Xinjiang expanded from 167.98 km² to 400.51 km², with the most significant growth observed in mountainous lakes. Monthly scale analysis revealed pronounced seasonal characteristics in the areal changes of these mountainous lakes. Statistical analysis indicated divergent responses of lakes at different altitudes to climatic changes. The substantial enlargement of lakes in Xinjiang’s mountainous regions is primarily attributed to climate change, particularly the rise in average annual temperatures. In the plains, human activities, especially irrigation, were identified as the primary drivers of lake area changes, while the impact of climatic factors was relatively minor.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-06-28 Cooperative journals: 《干旱区研究》
Abstract： 胡杨作为塔里木河荒漠河岸林的关键树种，对水土保持、抑制沙漠化等发挥着重要的生态作用。胡杨生物量是研究荒漠河岸林生态系统的功能与服务的重要指标。胡杨是国家二级保护树种，也是扎根沙漠的唯一乔木树种，十分珍贵，难以大规模使用破坏性方法进行测量，因此针对胡杨的生物量计算一直是个难题。通过对胡杨破坏性较低的采样方法，提取不同树干高度下的胡杨树轮信息，实验结果表明 ：①不同高度的树轮生长量之间存在显著的相关性，平均相关性系数为0.878；在树干0~0.5 m、0.5~1 m、1~1.5 m、1.5~2 m和2~2.5 m 高度的树干密度分别为500.2 kgm-3、475.6 kgm-3、502.2 kgm-3、477.2 kgm-3和420.194 kgm-3，平均密度为471.4 kgm-3，标准差为32.7；②在获得树干不同高度下的树轮信息和树干密度基础上，可以准确计算出1株胡杨树干年生物量，在实验中1株胡杨树干的0.5~1.5 m高度处，长为1m的树干在19972013年的年新增生物量为0.61~1.54 kg，年均新增生物量为0.92 kg，在20022003年生物量增幅明显,年均新增生物量为1.54 kg。笔者使用的树干生物量计算方法对林木破坏性小且可操作性强，能计算出树干新增生物量，对研究胡杨新增生物量和生态价值的变化具有重要意义。
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