中文摘要：

在全面调查内蒙古锡林河流域植被分布格局的基础上,采用国际上广泛使用的In VEST模型对锡林河流域草地生态系统水源涵养功能的空间特征进行研究。结果表明：全流域多年平均水源涵养总量为3.98×107m3·a（-1）,单位面积水源涵养量为40.68 m3·hm（-2）;流域水源涵养功能从上游至下游呈递减趋势;在各草地植被类型中,草甸草原的水源涵养功能最强,沙地植被和农田次之,草甸等其他类型最差;流域草地生态系统的水源涵养功能差异明显,其中,典型草原的水源涵养功能是草甸草原的50%。在典型草原内部,克氏针茅草原的水源涵养功能分别是羊草草原和大针茅草原的44.69%和56.06%。因此,在提高典型草原水源涵养功能的同时,应提高克氏针茅草原的水源涵养能力,这也是今后锡林河流域水土防治的重点。

英文摘要：

Based on the comprehensive survey of the vegetation pattern in the Xilin River Basin,Inner Mongolia,China,in this study the water conservation function in grassland ecosystem in the basin was assessed using the InVEST（ Integrated Value and Tradeoff of Ecosystem Service Tools） model,and the spatial pattern of water conservation function was analyzed. The results showed that the water conservation capacity per unit area was 40. 68 m~3·hm~（-2）,and the annual water conservation capacity in the whole drainage basin was 3. 98 × 107m~3. Spatially,the water conservation function decreased from the upper reaches to the lower reaches. The water conservation capability of meadow steppe was the highest,than that of sand vegetation and farmland,and that of meadow and others was the poorest. There were obvious differences in water conservation capability among the grassland types. The water conservation capability of typical steppe was about 50% of meadow steppe. Within the typical steppe,the water conservation capability of Stipa krylovii steppe was 44. 69% and 56. 06% of that of Leymus chinensis steppe and S.grandis steppe respectively. Therefore,the water conservation capability of both typical steppe and S. krylovii steppe should be improved,which should also be the emphasis in water and soil conservation in the Xilin River Basin.