两种沉水植物分解过程及温度影响的模拟研究

实验室模拟条件下,对采自大明湖的两种沉水植物菹草(Potamogeton crispus L.)和篦齿眼子菜(Potamogeon pectinatus L.)在不同温度和不同生物量密度条件下进行60 d的分解实验,研究沉水植物茎叶分解及C、N、P元素释放过程。实验结果表明:两种沉水植物分解速率很快,并且呈现前期快、后期慢的阶段性特征,菹草的分解速率大于篦齿眼子菜。沉水植物茎叶残留物分解过程中营养元素含量的变化,主要受植物组织化学组成影响。温度影响沉水植物的分解过程,高温加速了两种沉水植物前期分解速率,但并没有增加最终分解比率。

Decomposition processes and simulation of two species of submerged plants under different temperatures

Decomposition experiment of two species of submerged plants collected from Daming Lake under different temperatures was performed under laboratory simulated conditions for 60 days. The objective of this research was to study the decomposition processes and nutrient dynamics of the two submerged plants. The results indicated that the decomposition rates of both submerged plants were very fast. The decomposition process showed that the decomposition rates were faster in early stage than in later stage for two submerged plants. And the decomposition rate of Potamogeton crispus was greater than that of Potamogeon pectinatus. The decomposition efficiency and nutrient dynamics in residues of two submerged plants under different decomposition stages were mainly influenced by the chemical compositions of two submerged plants. The decomposition process was affected by water temperature. The higher temperature significantly accelerated the decomposition rate in the early stage for two submerged plants, but did not increase the final decomposition efficiency for two submerged plants.