制浆造纸废水排放对水生态系统影响研究

Study on Effects of Pulp and Paper Wastewater Discharge on Water Ecosystem

关键词:  制浆造纸废水  河口  底栖动物  群落结构  环境因子

Key Words:pulp and paper wastewater  estuary  macrobenthos  community structure  environmental factors

摘要:本研究通过理化分析和底栖动物群落调查，评估了制浆造纸废水排放对流域生态环境的影响，并通过相关性分析，识别了干扰底栖动物群落结构的环境因子。结果显示，受制浆造纸废水排放影响，沉积物样品总氮（TN）、总磷（TP）及有机碳（OC）呈现排污口处高，上、下游低的趋势；排污口S4处的UV₂₅₄值（波长254 nm处吸光度，用于表征芳香类污染物）最高，是上游S1处的4.25倍。各采样点Shannon-wiener多样性指数范围为0.47~1.8，Pielou均匀度指数范围为0.47~0.92，均处于较低水平；排污口S4处底栖动物类群仅有2种，密度（56.00 ind/m²）及生物量（4.18 g/m²）均低于上游，且耐污能力较强的多毛纲是单一的底栖动物类群；pH值、TP、UV₂₅₄及荧光区域II的积分标准体积（Φ_2,5）是影响生物群落结构的主要环境因子。以上结果表明，制浆造纸废水排放不仅改变了河口沉积物的化学组分，甚至会破坏底栖动物的栖息环境，降低生物多样性。

Abstract:In this study， physicochemical analysis and investigations into the benthic community were used to assess the environmental impacts of pulp and paper wastewater discharge on watershed ecosystem. Correlation analysis was conducted to identify the environmental factors influencing the structure of benthic community. The results showed that the concentrations of total nitrogen （TN）， total phosphorus （TP）， and organic carbon （OC） in the sediment samples were notably higher at the discharge point， decreasing towards the upstream and downstream areas affected by the discharge of pulp and paper wastewater. The absorbance at 254 nm（UV₂₅₄ value） that characterized aromatic pollutants， was the highest at sewer outfall S4， being 4.25 times that of upstream S1. The Shannon-wiener diversity index ranged from 0.47 to 1.8 and the Pielou evenness index ranged from 0.47 to 0.92 at each sampling point. Both indexes were at a relatively low level. Only two benthic species were subsisted at sewer outfall S4， the densities （56.00 ind/m²） and biomass of benthic organisms （4.18 g/m²） were lower at the discharge point compared to upstream， and the exception of the polychaetes， were more tolerant to pollution， being the predominant group. Correlation analysis indicated that pH value， TP， UV₂₅₄ and normalized integral volume of fluorescence region II （Φ_2，5） were the main factors influencing biome structure. Pulp and paper wastewater discharge not only changed the chemical composition of river sediments， but also disrupted the habitat of benthic organisms， leading to a reduction in biodiversity.