风车草和香根草在人工湿地中迁移养分能力的比较研究

为研究风车草(Cyperus alternifolius)和香根草(Vetiveria zizanioides)迁移养分的能力,建立17.0m²风车草潜流式人工湿地和13.3 m²香根草潜流式人工湿地处理猪场废水,在四个季节末测定植物生物量和组织氮、磷、铜、锌含量.结果表明,香根草地下部生物量大于风车草,地上部生物量则是风车草大于香根草.风车草年地上部收获量为3406.47 g·m^-2,比香根草的1483.88 g·m^-2高2.3倍;风车草的氮含量为22.69 mg·g^-1,比香根草的15.44 mg·g^-1高7.25 mg·g^-1;风车草的磷含量为6.09 mg·g^-1,比香根草的5.47 mg·g^-1高0.62 mg·g^-1.植株含铜、锌量风车草略比香根草高.风车草每年迁移N 68.72 g·m^-2和P18.49 g·m^-2,香根草迁移N 8.93 g·m^-2和P 3.69 g·m^-2.风车草人工湿地每年由植物迁移的氮、磷、铜、锌比香根草高4～7倍.

Comparison of nutrient removal ability between Cyperus alternifolius and Vetiveria zizanioides in constructed wetlands

In order to compare the nutrient removal ability of Cyperus alternifolius and Vetiveria zizanioides,a 17.0 m² subsurface flow wetland covered with Cyperus alternifolius and another 13.3 m² one covered with Vetiveria zizanioides were constructed for piggery wastewater treatment,and the biomass as well as the N,P,Cu and Zn contents in the root and shoot of the plants was measured by the end of each season.The results showed that the below-ground biomass of V.zizanioides was greater than that of C.alternifolius.By the contrary,the above-ground biomass of C.alternifolius was greater than that of V.zizanioides.The annual biomass yield of C.alternifolius was 2.3 times higher than that of V.zizanioides,which was 3406.47g·m^-2 and 1483.88 g·m^-2,respectively.The N concentration in C.alternifolius tissue was higher than that in V.zizanioides tissue,being 22.69 mg·g^-1 and 15.44 mg·g^-1 respectively,and similarly,the P concentration in C.alternifolius tissue was higher than that in V.zizanioides tissue,being 6.09 mg·g^-1 and 5.47 mg·g^-1 respectively.The Cu and Zn concentrations in C.alternifolius tissue were a little higher than those in V.zizanioides.68.72 g N·m^-2 and 18.49 g P·m^-2 were removed by harvesting C.alternifolius vegetation,while 8.93 g N·m^-2 and 3.69 g·P m^-2 were removed by harvesting V.zizanioides vegetation.It was concluded that the removals of N,P,Cu and Zn by harvesting vegetation were 4～7 times higher in C.alternifolius wetland than in V.zizanioides wetland.