Subjects: Geosciences >> Atmospheric Sciences submitted time 2023-03-15 Cooperative journals: 《干旱区地理》
Abstract： As the main carrier of alpine freshwater ecosystems, alpine lakes are currently experiencing rapid climate change that has profound and complex effects on their ecosystems. In this study, we systematically analyze the effects of altitude-dependent warming on the thermal properties, dissolved oxygen stratification, and biological processes of alpine lakes in the context of climate change, describe the adaptation measures of alpine aquatic organisms and changes in underwater radiation characteristics in the context of radiation enhancement, and reveal the effects of precipitation changes on the cross-ecosystem material subsidies and biogeochemical cycles in alpine lakes, as well as the mechanism of the impact of precipitation changes on these cross-ecosystem material subsidies and biogeochemical cycles in mountain lakes. In the future research, we must improve the integrated response experiments of lake habitats under the changes of multiple climate factors, strengthen the systematic monitoring and integration of the whole elements of alpine lake ecosystems, and change the research type (i.e., static and qualitative research to process, dynamic, and quantitative research) to enhance knowledge on the response mechanism of alpine lake ecosystems to global climate change.
Subjects: Geosciences >> Hydrology submitted time 2022-12-20 Cooperative journals: 《干旱区研究》
Abstract：
Based on the satellite data, the water level and area information of Lake Issyk-Kul was extracted, and the water volume was reconstruct; combined with CRU meteorological data from 1960-2020, the temperature and precipitation observation data from 1960- 2000 at the Cholpon- Ata meteorological station and the water volume observation data into the lake, the lake water balance model was established to analyze the changing characteristics of each element of the water balance and to explore its influencing factors. The results indicated that: (1) Since 1960, the water volume of Issyk-Kul Lake has undergone a process of continuous decrease and fluctuating increase, with 1998 being the inflection point of the change; from the 1960s to the mid-1980s, the water volume into the lake decreased continuously mainly due to the influence of irrigation diversions, and then turned to an increasing trend after 1986 with the decrease of irrigation water and the increase of precipitation and glacial meltwater; precipitation in the lake area increased at a rate of 9.1 mm·(10a)-1 , and the evapotranspiration tends to increase significantly with increasing temperature and lake area. (2) Before the mid-1980s, Issyk-Kul had a negative water balance in most years, and groundwater continued to recharge the lake; since 1986, the water balance deficit of the lake gradually decreased, and since 1998, the positive balance has been dominated. (3) The interaction of water balance components such as runoff, precipitation and evaporation determines the changes in lake water volume, while climate change in the flow-producing areas and irrigation diversions in irrigation areas indirectly drive the changes in lake water volume by changing runoff; from 1960 to 1986, human activities, mainly irrigation diversions, were the dominant factor driving the changes in Issyk- Kul water volume, with a contribution of 71.6%, and since 1987 the cumulative contribution of climate change factors to changes in lake water volume exceeds 80%.
Subjects: Geosciences >> Geography submitted time 2022-03-28 Cooperative journals: 《干旱区研究》
Abstract：本文基于水文观测和遥感监测数据，获取近60 a巴尔喀什湖面积、水位变化信息，重建湖泊水量变化时间序列，探明巴尔喀什湖水量变化特征；依据湖泊水量收入（入湖径流、降水）支出（湖面蒸发）建立巴尔喀什湖水量平衡模型，分析巴尔喀什湖水量平衡要素变化特征，定量解析气候变化和人类活动对巴湖水量变化的影响。结果表明：（1）19612020年，巴尔喀什湖水量以1987年为拐点先急剧减少后波动增加；入湖径流变化与湖泊水量变化过程基本一致，年均入湖径流量约为14.04 km3a-1；湖区降水以0.28 mma-1的速率波动增加；水体年均蒸发量约17.95km3a-1，其中，1987年最小为16.10 km3，2008年最高达20.30 km3。（2）过去60 a年，地下水与湖泊互为补充，其中20世纪70年代和80年代地下水补给湖泊水量较多，补给量约为1.91 km3。（3）在湖区尺度上，入湖流量与巴尔喀什湖水量显著相关，是影响湖泊水量变化的主导因素；在流域尺度上，气候波动对入湖流量长期变化的贡献率为71.67%，人类活动耗水的贡献率为28.33%；19701985年卡普恰盖水库蓄水及周边耕地扩张对入湖水量锐减的贡献率达47.47%，人类活动明显加剧了这一时期湖泊水位下降的进程。
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