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冰川冻土 ›› 2000, Vol. 22 ›› Issue (3): 200-205.

• 研究论文 • 上一篇    下一篇

黄河源区生态环境变化与成因分析

王根绪1,2, 沈永平1, 程国栋1   

  1. 1. 中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室, 甘肃兰州730000;
    2. 兰州大学资源环境学院, 甘肃兰州730000
  • 收稿日期:2000-03-21 修回日期:2000-05-09 出版日期:2000-08-25 发布日期:2012-04-26
  • 基金资助:
    中国科学院寒区旱区环境与工程研究所创新项目(210042);中国科学院"西部之光"支持项目;中国科学院特别支持项目"冰冻圈动态变化基础研究(三)"资助

Eco-environmental Changes and Causal Analysis in the Source Regions of the Yellow River

WANG Gen-xu1,2, SHEN Yong-ping1, CHENG Guo-dong1   

  1. 1. State Key Laboratory of Frozen Soil Engineering, CAREERI, CAS, Lanzhou Gansu 730000, China;
    2. Resource and Environment College of Lanzhou University Lanzhou Gansu 730000, China
  • Received:2000-03-21 Revised:2000-05-09 Online:2000-08-25 Published:2012-04-26

摘要: 以70年代、80年代和90年代3个时期的卫星影像资料为基础.结合野外调查.对70年代以来黄河源区生态环境演变过程及趋势进行了对比分析,并依据相同时期的气候变化、人为活动强度分析,对该区域生态环境变化的产生原因进行了探讨.研究结果表明,与70年代相比,80年代和90年代以高寒沼泽草甸、高寒草甸和高山草原化草甸为代表的主要生态体系均呈现明显退化,尤其是90年代中期以来,高寒草原与高寒草甸植被退化剧烈,荒漠化发展迅速,其主要原因在于区域气候干暖化及其引起的多年冻土退化.

关键词: 黄河源区, 生态环境演变, 过程, 气候变化:冻土退化

Abstract: Based on three phases of satellite image data and field investigation, the eco-environmental evolution processes since the 1970s were analyzed. Analyses and discussions were made in this paper aimed at the understanding of the trend and causes of eco-environment changes in the regions over the last 20 a. The causes responsible for the environmental changes in the regions were explored in accordance with climate change and human activity. It is found that the eco-environment in the source regions of the Yellow River markedly degraded during the period of the 1980s-1990s compared with the 1970s. Especially from the mid-1990s, high-cold grassland and high-cold meadow vegetations seriously degraded, together with rapid desertification. The area of vegetation degradation increased from 24.5% in the 1980s to 34.5% of the total area of grassland and high-cold meadow in the 1990s. The expanding rate of desertification increased from 3.96% in the 1980s to 34.72% in the 1990s. Climate in the regions is becoming dry and warm, and permafrost is gradually degrading. Air temperature in the source regions of the Yellow River has been rising since 1954. Permafrost environment of the regions altered markedly, with an expansion of thawed.area and an increase in seasona thawing depth. Degradation of Permafrost led to a decrease of soil moisture content in root zone and surface soil desertification. In spite of this, summer precipitation in the regions also showed a decreasing tendency. Such regional climate change is not favorable for the normal growth of vegetation and thus will be causing extensive vegetation degradation. At the statuse of present the seasonal distribution of rangelands is unbalanced and irrational use. Consequently, cold-season rangelands are seriously overgrazed and thus causing pasture degradation. In addition, rodent and insect damages in the headwaiers are serious, covering 6%~21 % of the total rangeland area.

Key words: source regions of the Yellow River, eco-environmental evolution, processes, climate change, permafrost degradation

中图分类号: 

  • P642.14