穗花狐尾藻(Myriophyllum spicatum L.)在不同程度富营养化水体中的营养积累特点及营养分配对策

通过对栽培于3个不同程度的富营养化水体(富营养化程度为水体1<水体2<水体3)中的穗花狐尾藻(MyriophyllumspicatumL.)进行研究,测定了不同时期植物体各个器官的氮磷含量及生物量分配,探讨了富营养化水对其营养积累及分配格局的影响。结果表明,重度富营养化的水体3中穗花狐尾藻组织中的氮含量显著高于其它两个水体;而由于水体1和水体2的氨态氮含量无显著差异,植物组织中的氮含量在水体1和水体2间无显著差异。富营养化程度高的水体2中植物磷的含量显著低于富营养化程度低的水体1中的植物,但在重度富营养化的水体3中,叶子的磷含量却远高于其它两个水体,这是由植物不同部位吸收的磷在各器官间分配不同所造成的。由于底泥的营养含量丰富,在3个不同程度的富营养化水体中,穗花狐尾藻的根冠比并未表现出明显差异。

Response of Nutrient Accumulation Characteristics and Nutrient Strategy of Myriophyllum spicatum L. under Different Eutrophication Conditions

From May to September in 2003, Myriophyllum spicatum L.was cultured in three (waters) with different degrees of eutrophication(the eutrophic conditions were water 1M.spicatum contents phosphorus 3).The 24-N content in water 1 and water 2 was similar.Phosphorus content in tissues in low eutrophic water 1 was higher than that in water 2.But in hypereutrophic water 3,phosphorus content in leaves was higher than that in (eutrophic) water 1 and 2,which was due to the absorbed phosphorus by different organs were not allocated to each organ at the same ratio.R∶S ratios of M.spicatum showed no significant difference among different (eutrophic) water 1,2 and 3 for the same rich sediment.