不同湿地模型净水效果与基质酶活性相关性的比较研究

为了研究不同植物和基质组合的小型湿地模型净水效果及其与基质酶活性(脲酶和磷酸酶)之间的相关性, 并选出净水效果最佳的模型, 通过对两种植物(茭白和慈姑)和两种基质(石榴石和磁铁矿)进行组合构建不同的湿地模型, 对不同湿地模型进出水口水质和基质酶活性进行测定并加以分析进行优化选择。结果表明: 湿地模型对亚硝态氮的去除率最高, 最高能达到98.87%, 最低也能达到58.06%, 对高锰酸盐的去除率最低, 最高37.91%, 最低2.51%; 湿地模型X5-X6对各污染物的去除率基本上都比X1-X4高, 总氮去除率平均高3%, 氨氮去除率平均高10%, 亚硝态氮去除率平均高10%, 总磷去除率平均高15%, 正磷酸盐去除率平均高20%, 高锰酸盐去除率平均高8%; 在相同种植数量的情况下, 茭白和慈姑混合种植的湿地模型总体上比茭白和慈姑单一种植的湿地模型具有更好的净水效果, 是实验中的最佳湿地模型; 湿地模型的脲酶活性与总氮去除率具有显著的相关性(相关系数为0.903—0.980), 脲酶可作为判定人工湿地去除养殖水体中总氮效能的指标, 湿地模型磷酸酶活性与高锰酸盐去除率总体上具有显著相关性(相关系数为0.821—0.992), 磷酸酶可作为判定人工湿地去除养殖水体中高锰酸盐效能的指标。研究为人工湿地植物和基质优化选择和基质酶活性评价净水效果提供了理论依据。

THE COMPARATIVE ANALYSIS OF THE SUBSTRATE ENZYME ACTIVITY AND WATER PURIFICATION EFFECT IN DIFFERENT WETLAND MICROCOSM

The aim of current research was to determine the most efficient model for water purification, by studying dif-ferent combinations of plants and matrixes and related enzyme activities (urease and phosphatase) in small wetland models. Two types of plants:Zizania latifolia and Sagittaria graminea, and two types of matrixes: garnet and mag-netite were used to construct six different wetland models. Within a wetland system, the quality of inflow and outflow water and the matrix enzyme activities were measured. The results indicated the wetland models have the highest re-moval rate of nitrite nitrogen, ranging between 98.87% and 58.06%, and the lowest removal rate of CODMn, ranging between 37.91% and 2.51%. Compared with the single plantation model, combination of both plant species yielded a synergy effect in improving water quality, evident by the increased average removal rates of total nitrogen (by 3%), am-monia nitrogen (by 10%), nitrite (10%), total phosphorus (15%), orthophosphate (20%), and CODMn (8%). This effect was independent of the use of matrix. The filter material urease activity was highly correlated with the total nitrogen re-moval rate (r2: 0.903—0.980), whereas phosphatase activity was highly correlated with the CODMn removal rate (r2:0.821—0.992). Hence, urease and phosphatase can be used as predictors of the total content of nitrogen and CODMn, re-spectively, in a wetland system. This research provides a theoretical basis in optimal selection of wetland plants and matrixes and in evaluation of water purification effect by assessing substrate enzyme activities.