不同修复模式下湿地水质变化的短期效应分析

A Short-Term Effect Analysis on the Change of Wetland Water Quality through Different Remediation Processes

为探讨不同修复模式对水质的影响,从2009-03-2010-03跟踪监测了精养鱼塘、人工修复水域以及自然修复区3种不同水环境的NO3--N、NH4--N,Chl a、DO、EC、TP、TN和COD等指标,从空间和时间的角度分析了人工修复和自然修复对水质的影响情况。结果表明：在修复研究期间,与精养鱼塘相比,人工修复区水体中TN、NO3--N、TP、Chl a、COD等指标经过修复中期的短暂上升后均有显著下降（P〈0.05）,水质有显著改善;自然修复区水质中TP、Chl a、COD等指标均有下降,而TN呈现显著上升（P〈0.05）,水质总体有小幅改善趋势。在适当的人为干扰下,人工修复区能够在短期内对水质产生显著的改善效果。因此,积极且适当的人为干扰的湿地修复比自然恢复对水质的改良效果更加显著。

From March 2009 till March 2010, water samples in three habitats （intensive fishponds, constructed wetlands and natural restoration area） were collected seasonally to monitor the water quality and analyse the restoration effects chronologically and spatially under different remediation processes. Parameters of the water quality included nitrate-N, ammonium-N, chlorophyll a, DO, EC, total phosphorus, total nitrogen, and COD. The monitoring data showed that, during the remediation study period, the parameters of total nitrogen, nitrate-N, total phosphorus, chlorophyll a and COD had short-term increases and then declined significantly （P 〈 0.05） in the constructed wetlands comparing with those in intensive fishponds. In the natural restoration area, contents of total phosphorus, chlorophyll a and COD in water decreased in some degree whilst total nitrogen evidently increased （P 〈 0.05） so as to indicate that the water quality there tended to be somewhat improved in general. The constructed wetlands under appropriate man-made intervention could improve the water quality efficiently in a short time. It was therefore concluded that constructed wetlands where appropriate intervention was exerted actively could have a better effect on the water quality improvement with comparison of the cases of natural restoration.