黄河首曲流域草地生态与自然环境退化成因及对策研究

Study on causes and strategy of grassland ecology and natural environment degeneration in the first meander of Yellow River

近50年来黄河首曲流域草场退化、沙化,水土流失,生物多样性减少,生态系统功能弱化。分析了黄河首曲流域气候、生态观测资料及统计资料,结果表明:造成生态与自然环境退化的主要原因是气候变化和环境蠕变。黄河首曲大部分区域降水量年际变化呈下降趋势,气温年际变化呈上升趋势,增温速度均大于全国增温速度。草地年干燥指数呈显著上升趋势,20世纪80年代末至2004年明显趋于干旱化,气候变化是草地生态退化的自然诱发因素。超载过牧、滥采乱挖、人为破坏、生物链失衡等环境蠕变是造成生态退化的人为因素。二者共同作用导致黄河首曲流域草地与湿地生态与自然环境退化。控制放牧、防止滥采乱挖、建立自然生态保护区是维护该区域生态系统平衡的措施。

Grassland eco-system in the first meander of Yellow River was weakened in the recent 50 years due to grassland deterioration, desertification, water and soil erosion and biodiversity reduction. Analysis of climate and ecological data and information indicated that the main cause of this degradation was climate and environment change. Most area of the first meander had decreasing precipitation and increasing air temperature, which was greater than average national increase. Annual drought index went up significantly from 1980s to 2004. Climate change was the natural inducing factor of grassland eco-degradation. Artificial factors included over grazing, excessive digging, and bio-chain imbalance, etc. Both caused deterioration of the grassland and wetland in the first meander of Yellow River. Measures should be taken to keep local eco-system balance such as controlling grazing, preventing excessive digging and establishing natural reserve.