狐尾藻和菖蒲对养猪场废水的净化效果及其根系形态

Purification Efficiency of Swine Wastewater by Myriophyllum spicatum and Acorus calamus and Their Root Morphology Characteristics

为了研究狐尾藻(Myriophyllum spicatum)和菖蒲(Acorus calamus)对养猪场废水的净化效果,开展了为期40 d的温室模拟培养实验。以狐尾藻和菖蒲为供试植物,按照蒸馏水与养猪场废水体积比分别为40:1、20:1、15:1、10:1和5:1,配制了5种实验用水,测定了各种配制水中的化学需氧量、氨氮、总氮和总磷含量,计算了其去除率;测量了两种植物的株高,计算了其生长速率,分析了两种植物植株的生长速率与各污染物去除率的关系,探讨了种植在各种配制水中的两种植物的根系形态特征。研究结果表明,狐尾藻和菖蒲对蒸馏水与废水体积比为40:1的配制水中的化学需氧量、总氮、总磷和氨氮的去除率都相对最大;在实验的第20天和第40天,种植在蒸馏水与废水体积比为20:1的配制水中的狐尾藻和菖蒲植株的生长速率都最大,其值分别为0.98 cm/d和1.17 cm/d(第20天)、1.76 cm/d和2.05 cm/d(第40天);狐尾藻植株的生长速率分别与各种配制水中的氨氮、总氮和总磷含量都显著负相关,而菖蒲植株的生长速率分别与各种配制水中的氨氮和总氮含量都显著负相关;种植在蒸馏水与废水的体积比为15:1的配制水中的狐尾藻和菖蒲植株的主根长、主根直径、根体积、根表面积和根系总长都显著大于种植在其它4种配制水中的狐尾藻和菖蒲;随着配制水中废水体积的增大,狐尾藻通过减少根表面积,菖蒲通过缩短根长,来适应生境。

To explore the purification effect of Myriophyllum spicatum and Acorus calamus on swine wastewater, a greenhouse simulation culture experiment of 40 days was carried out. Myriophyllum spicatum and Acorus calamus were used to carry out the experiments. Five kinds of prepared water were prepared including volume ratios of distilled water and wastewater with 40:1, 20:1, 15:1, 10:1 and 5:1. Contents of chemical oxygen demand, ammonia nitrogen, total nitrogen and total phosphorus in five kinds of prepared water were determined and the removal efficiency was calculated. Growth rates of Myriophyllum spicatum and Acorus calamus were calculated. The root morphology of Myriophyllum spicatum and Acorus calamus including main root length, diameter, volume, surface area and total root length in aquaculture wastewater was compared. The relationship between growth rates and pollutants concentrations was analyzed. The results showed that in the prepared water of volume ratio of distilled water and wastewater with 40:1, the chemical oxygen demand, total nitrogen, total phosphorus and ammonia nitrogen removal efficiency reached maximum.In the prepared water of volume ratio of distilled water and wastewater with 20:1, the growth rates of Myriophyllum spicatum and Acorus calamus were highest on the 20th day and the 40th day, which were 0.98cm/d and 1.17 cm/d, 1.76 cm/d and 2.05 cm/d, respectively. Growth rates of Myriophyllum spicatum were negatively correlated with ammonia nitrogen, total nitrogen and total phosphorus concentrations, while that of Acorus calamus was negatively correlated with ammonia nitrogen and total nitrogen concentrations. In the prepared water of volume ratio of 15:1, the parameters of main root length, main root diameter, root volume,root surface area and total root length of Myriophyllum spicatum and Acorus calamus were significantly higher than those of other four treatments. In order to adapt the environmental stress, Myriophyllum spicatum decreased root surface area while Acorus calamus shortened root length for adaptation strategies.