贡嘎山海螺沟典型植被带总磷分布特征

Characteristic of Total Phosphorus Distribution in Typical Vegetation Zones Along Hailuogou of Gongga Mountain

由于独特的生物地球化学循环方式,磷已成为影响山地生态系统发育和安全的重要元素。为了了解贡嘎山磷的生物地球化学循环,对贡嘎山海螺沟坡地典型植被带土壤、植物根际土壤、植物不同部位总磷在生长季(9月)和非生长季或生长季初期(5月)的分布特征进行调查。结果表明:土壤总磷的分布在垂直梯度上的差异以及同一土壤剖面不同土壤层总磷的差异均较明显,同时还呈现明显的季节性差异,这些差异的形成与土壤发育程度、温度变化及植物生长有关;不同根际土壤在非生长季或生长季初期总磷的差异非常大,而在生长季较为接近,进一步说明植物对山地磷的生物地球化学循环存在较大影响;杜鹃、冬瓜杨、柳的叶较幼枝更富集磷,而峨眉冷杉、麦吊杉、竹的幼枝较叶所含磷略高。

Phosphorus is an essential nutrient for mountain ecosystem development and security because of the special biogeochemical cycle. In order to understand the biogeochemical cycle of phosphorus in Gongga Mountain, the distributions of total phosphorus in soil from typical vegetation zone, rhizospheric soil and different parts of plants at growing season （September） and non-growing season or the beginning of growing season （May） were investigated. The results showed that the difference of distribution of total phosphorus in vertical gradient and that in different soil horizons from the same soil profile were significant, and the seasonal difference was remarkable; the above differences were related with the degree of soil development, temperature change and plant growing; the difference of total phosphorus in different rhizospheric soils at non-growing season or the beginning of growing season was large, but the difference at growing season was close, so that the plant had significant impact on the biogeochemical cycle of phosphorus in mountain; phosphorus in leaf was more than that in young shoot for rhododendron, populus purdomii and willow, while phosphorus in young shoot was a little more than that in leaf for abies fabric, picea brachytyla and bamboo.