油蒿群落不同演替阶段某些群落特征的研究

STUDY ON SOME FEATURES OF ARTEMISIA ORDOSICA COMMUNITY AT THE DIFFERENT SUCCESSIONAL STAGES

本文就鄂尔多斯高原毛乌素沙地油蒿群落不同演替阶段的特征进行了研究。结果表明：流动沙地质地疏松，植物种类少、稀疏，群落冠层温度变化剧烈，相对湿度低，油蒿生长旺盛，其叶的含水量、水势、蒸腾强度高；固定沙地，植物种类增多、覆盖度大、生物量高，缓冲气象因子的能力强。但蒸腾失水量大，致使土壤含水量低，在某种程度上限制了油蒿生长；具结皮的固定沙地，植物种类最多，密度最大，但土壤紧实，油蒿生长微弱，其叶的含水量、水势最低，但蒸腾最大，加速失水。其演替趋势为流动沙地→流动沙地油蒿群落→固定沙地油蒿群落→具结皮的固定沙地油蒿＋本氏针茅群落→本氏针茅群落。

Artemisia ordosica community in Maowusu sandland of China showed different features at the successional stages.The stage of shifting sandland was of loose soil,few plants,the lowest relative humidity,drastically changing temperature,and of vigorous growth of A.ordosica with its high leaf water content,water potential and transpiration rate.The stage of fixing sandland was of more plants,the highest plant coverage,biomass and loosing water,the highest relative humidity,and the lowest soil water.The stage of fixed sandland with A.ordosica+Stipa bungeana and crust of mosses and algae was of the most plants,the highest soil water content,and of tight soil preventing the growth of A.ordosica with the lowest leaf water content and water potential,and with the highest leaf transpiration rate.The successional series of A.ordosica community were:shifting sandland,A.ordosica community of fixed sandland,A.ordosica+S.bungeana community,and S.bungeana community.