五种水生植物生物量及其对生态沟渠氮、磷吸收效果的研究

BIOMASS AND EFFECTS OF FIVE AQUATIC PLANTS UPTAKE OF NITROGEN AND PHOSPHORUS IN ECOLOGICAL DITCH

为明确水生植物对农田排水沟渠中氮、磷吸收效果的影响,本研究以生态沟渠中水生美人蕉、铜钱草、黑三棱、狐尾藻和灯心草为试验植物,对5种水生植物的生物量以及吸收、累积的氮、磷量进行测定。结果表明:不同水生植物生物量有差异,平均总生物量在1.10～2.43kg/m2之间,其中以水生美人蕉的生物量最大,达2.43kg/m2。5种水生植物地上部分的氮、磷浓度分别在8.41～20.67g/kg和1.41～3.40g/kg之间,狐尾藻氮、磷浓度最高;而地下部分的氮、磷浓度分别在4.41～10.47g/kg及1.08～1.90g/kg之间,不同水生植物间差异显著,以狐尾藻氮浓度和铜钱草磷浓度为最高;地上部分氮、磷累积量的变化范围分别7.40～28.23g/m2和1.13～4.49g/m2,其中以水生美人蕉对氮的累积量为最大,狐尾藻对磷的累积量为最大。5种水生植物地上部分氮、磷累积量均高于地下部分。地上部分收割后,5种水生植物单次可带走氮、磷分别在7.40～28.23g/m2和1.13～4.49g/m2,水生美人蕉带走的氮最多;全年可带走的总氮和总磷量分别为20.34～109.12g/m2a和3.41～17.95g/m2a,狐尾藻带走的最多。水生植物地上部分通过收割的方法可有效去除沟渠中的氮磷,还能解决水生植物的二次污染问题。

The objective of this study is to determine the absorption effects of aquatic plants of nitrogen and phosphorus in field drainage ditch.Five aquatic plants of Canna glauca,Hydrocotyle vulgaris,Sparganium stoloniferum,Myriophyllum verticillatum and Juncus effusesin ecological ditch were used to investigate biomass,contents and accumulation of nitrogen and phosphorus.Results indicated that there were some differences in biomass among different aquatic plants with the whole biomass of 1.10~2.43kg/m2,and Canna glauca were the highest,2.43kg/m2 among five aquatic plants.The nitrogen and phosphorus concentrations among five aquatic plants varied in the aboveground ranging between 8.41-20.67g/kg and 1.41-3.40g/kg,respectively,and Myriophyllum verticillatum were the highest.The nitrogen and phosphorus concentrations among five aquatic plants changed in the underground ranging between 4.41-10.47g/kg and 1.08-1.90g/kg,respectively,there was significant difference in different aquatic plants,the underground nitrogen concentrations of Myriophyllum verticillatum and phosphorus concentrations of Hydrocot ylevulgaris were the highest.Aboveground accumulation of nitrogen and phosphorus in aquatic plants were 7.40g/m2-28.23g/m2 and 1.13g/m2-4.49g/m2 respectively.Aboveground accumulation of nitrogen of Canna glauca and accumulation of phosphorus of Myriophyllum verticillatum were the highest,the five aquatic plants aboveground accumulation of nitrogen and phosphorus was higher than underground.After harvesting five aquatic plants aboveground,the_removal amounts of nitrogen and phosphorus were 7.40-28.23 g/m2 and 1.13-4.49g/m2 respectively with Canna glauca the highest.The removal amounts of nitrogen and phosphorus were 20.34~109.12g/m2a1 and 3.41~17.95 g/m2a1 the whole year,respectively,and Myriophyllum verticillatum were the highest.Through harvesting aquatic plants aboveground can efficiently remove nitrogen and phosphorus in ditches and can solve the one more pollution problem of aquatic plants.