摘要
在哈尔滨地区面积6 600 m2、平均水深1.2 m、多年未清淤的泥沙底质典型淡水精养池溏中混养鲤(Cyprinus carpio)、鲇(Silurus asotus)、草鱼(Ctenopharyngodon idella)和鲢(Hypophthalmichthys molitrix),春季(4-5月)、夏季(6-8月)和秋季(9月)不同时间采集池塘水体和表层底泥样品,监测养殖周期内水质总氮(TN)、总磷(TP)、氨氮(NH4+-N)、亚硝酸盐氮(NO2--N)、硝酸盐氮(NO3--N)和总有机碳(TOC)含量及高锰酸盐指数(CODMn)、pH的季节性变化,利用单项污染指数法、综合污染指数法评价水体污染程度,利用主成分分析法解析水质污染的主要驱动因子,并结合底质指标绘制网络关系图.结果表明:池塘水质整体处于严重污染水平,春季优于夏季和秋季.参与评价时池塘水质为Ⅳ类、Ⅴ类和劣Ⅴ类,水质超标数随着养殖时间延长而增加,TN在全养殖周期内均超出警戒水平;TN、TP、NH4+-N和CODMn是池塘水体的主要污染物.因子分析结果表明,池塘水质主要受鱼类的生长代谢、溶解氧和投饵的影响,污染物以N、P营养盐为主.水体TP、TN、NH4+-N和底泥NO2--N呈极显著正相关关系(P＜0.01),与底泥TOC呈显著正相关关系(P＜0.05).池塘水体和底泥中的有机物污染具有共现性,水体TOC和底泥TOC呈极显著正相关关系(P＜0.01).
Abstract
The seasonal changes in contents of total nitrogen(TN),total phosphorus(TP),ammonia nitrogen(NH4+-N),nitrite nitrogen(NO2--N),nitrate nitrogen(NO3--N),total organic carbon(TOC),and permanganate index(CODMn)and pH value were monitored during the culture period,and the degree of water pollution was evaluated in water and sediments in a typical intensive freshwater pond with area of 6 600 m2,average water depth of 1.2 m,many years of uncleared sediment bottom with polyculture of common carp(Cyprinus carpio),catfish(Silurus asotus),grass carp(Ctenopharyngodon idella)and silver carp(Hypophthalmichthys molitrix)in Harbin in spring(April-May),summer(June-August)and autumn(September)by using the single pollution index method and the comprehensive pollution index method.The main drivers of water pollution were analyzed by principal component analysis,and the network relationship diagram was drawn based on substrate indices.The results showed that the pond water quality was found to be at a severe pollution level,with better in spring than in summer and autumn.In the evaluation,the pond water quality was classified as Class Ⅳ,Class Ⅴ and poor Class Ⅴ.The levels of exceeding water quality standard were increased with the extension of breeding time,and TN exceeded the warning level in the whole culture period.The contents of TN,TP,NH4+-N and CODMn were the main pollutants in the pond water.The results of factor analysis revealed that the water quality in the pond was mainly affected by the growth and metabolism of fish,dissolved oxygen level and feeding rate,with the primarily pollutants of N and P nutrients.There was a significant positive correlation between TP,TN,NH4+-N and sediment NO2--N(P＜0.01),and there was a significant positive correlation between TP,TN,NH4+-N and sediment TOC(P＜0.05).There was a co-occurrence of organic pollution in pond water and sediment,and there was a very significant positive correlation between water TOC and sediment TOC(P＜0.01).
基金项目
中央级公益性科研院所基本科研业务费专项(HSY202102M)
国家自然科学基金青年基金(32102855)
中国博士后科学基金(2021MD703899)
维普
万方数据