黄土高原西部兰州市郊植被的水环境响应

Response to Soil Water Environment of Vegetation in Lanzhou Suburb on Western Loess Plateau

通过调查兰州南北两山及周边地区的植被类型、生长状况以及土壤水分等因子,分析了植被的生长与气候环境的关系,对在兰州地区造林绿化的适应性以及各地植被分布的类型、特征进行了深入的分析。结果表明,年降水量是决定植被生长状况最关键的因子,兰州市周边地区的植被分布状况基本是东部稍好于南部,南部显著好于北部。东部和南部植被以乔木为主,北部以耐旱灌木为主。不论乔木和灌木,保障土壤含水量常年处于5%以上是人工造林可持续发展的底线。

By investigating vegetation types and growth status, soil water and other factors of southern and northern mountains of Lanzhou and surrounding areas, we analyzed the relation between vegetation growth and climate environment, then deeply analyzed the afforestation adaptation, types and characters of vegetation distribution in Lanzhou. The results showed that annual rainfall was an important factor to determining vegetation growth status; the vegetation distribution status of eastern areas was better than that in southern areas, and that in southern areas was better than that in northern areas. Arbores were the predominant in eastern and southern areas, whereas drought-tolerant shrubs were the predominant in northern areas. Whether arbores or shrubs, the soil water content of 5 % is the lowest threshold to keep the sustainable development of planted forest.