石羊河流域中下游湿地–荒漠芦苇种群生长特征研究

A Research on Growth Characteristics of Phragmites australis Population from Wetland to Desert in Middle and Lower Reaches of Shiyang River Water-Shed Area

摘要: 芦苇是石羊河流域荒漠区主要建群植物种群，从湿地到雨养荒漠区均有分布，并随水文、土壤、气候、植被等生境因子变化而形成了不同的生态型。研究表明：荒漠湿地芦苇密集分布，生长最为旺盛，地下水位在2 m以内多芦苇优势植物群落，并随着离湿地水面距离增加，地下水位下降，芦苇种群密度、生长量减低，植被覆盖度也逐渐降低，直至雨养荒漠区都有稀疏或零星的芦苇生长；同时，土壤盐分、pH值也抑制着芦苇种群的生长发育，其水、盐、干旱三大因素显著影响着芦苇的分布与生长发育。

Abstract: Phragmites australis is the dominant population of desert vegetation communities in Shiyang River water-shed area, it is distributed extensively from wetland to rain-fed desert areas, changed with habitat factors of hydrology, soil, climate and vegetation and formed some different eco-types. The research showed that Phragmites australis communities are densely distributed, growth is the best in the wetland and more its communities when groundwater table is less than 2 m, with the distance increasing to the water area, groundwater table declines, its population density, growth and vegetation coverage are reduced; in the meanwhile, soil salt content, pH value are also limited its distribution and growth, the three key factors of habitat hydrology, salt and drought limited the distribution and growth obviously.