黑河流域中游水陆交错带湿地芦苇种群动态变化特征

Dynamics changes characteristics of Phragmites australis population in land-lake ecotone wetland in the Heihe River Basin

对自然状态下黑河流域中游水陆交错带湿地芦苇(Phragmites australis)种群生态特征以及地表淹水深度进行调查,分析该区芦苇种群的盖度、高度、密度和地上生物量等生态特征的季节变化和地表水位变化对芦苇种群生态特征的影响。结果表明:黑河中游水陆交错带湿地芦苇种群的生长过程具有明显季节性规律,盖度随着季节的推移呈先升高后下降的趋势,最高值出现在8月下旬,为99.7%;高度则随着季节的推移逐渐升高;密度随着季节的变化具有先升高后下降再升高的特点;地上生物量在5～6月、7～8月间增长较快,6～7月间增长相对较慢,8月下旬达到最大值,随后逐渐减少。淹水深度对芦苇种群的生态特征有显著影响,种群盖度、高度、密度、地上生物量的变化速率与淹水深度变化速率均有显著相关性(p<0.05)。

Phragmites australis population ecology characteristics and the surface inundated depth of the natural state land-lake ecotone wetland of Heihe River Basin were investigated,and the coverage,height,density and ground biomass of P.australis population were analyzed.The results are as follows.The growth process of land-lake ecotone wetland of P.australis population had obvious seasonal rule.P.australis population coverage showed a trend of increasing first but decreasing later with seasons,with its peak of 99.7% in late August.P.australis population height increased with the seasons.P.australis population density had a tendency of increasing,decreasing and increasing with the seasons.P.australis population ground biomass increased rapidly during May to June,and during July to August,but increased slowly during June to July,and it peaked at August,after when it decreased gradually.The flooded depth had a significant effect on P.australis population ecological characteristics.Coverage,height,density and biomass rates of population were significantly related with the change flooded depth（p0.05）.