灌溉对退化草地的恢复作用

Study on Effect of Irrigation for Degraded Grassland Recovery

由于气候干旱加之超载过牧使得草地退化严重，不仅限制了当地的经济发展，而且也威胁京津地区生态安全。因此，治理退化草地以及防止草地进一步退化迫在眉睫。然而光靠环境自身的修复能力，不但耗时较长，而且受环境因素影响较大，因此有必要通过人工干预措施加速退化草地的恢复。通过在希拉穆仁草原的灌溉实验，对测试的实验地内进行植被调查、土壤肥力化验和土壤种子库发芽试验，结果表明：灌溉可以提高建群种高度、植被盖度、地上生物量；土壤0～5cm细粒物质增加，0～20cm N、P和有机质含量不同程度增加；土壤种子库得到改善。灌溉对退化草地的恢复作用明显。

Due to the drought climate and over grazing, the grassland degrades severely. This is not only restricts local economy, but also threatens ecology safety of areas around Beijing and Tianjin City. Urgently control of degraded grassland and preventing farther deterioration are needed. Self-recovery of grassland spends long time and is significantly affected by the environment. So it is necessary to help the nature by artificial approaches. Through irrigation experiment in Xilamuren grassland, the vegetation, soil fertility and soil seed bank are analyzed. The result shows that irrigation can enhance the constructive specie, coverage and aboveground biomass, fine grains in the soil layer of 0-5 cm depth is increased due to vegetation improvement, the content of N, P and organic matter in the soil layer of 0-20 cm depth are increased, and the soil seed bank is improved. So irrigation plays a vital role in recovery of degraded grassland.