西溪国家湿地公园水质时空分异特征研究

西溪湿地公园作为第一个国家湿地公园和城市湿地公园的代表,具有特殊的功能特征.利用2009年春夏两季对西溪湿地水质的月监测数据,揭示城市湿地公园水质时空分异和污染特征.结果表明,①湿地水质空间分异与公园功能特征密切相关.其中,自然水塘的TN、TP平均值分别为0.78 mg/L和0.07 mg/L;观赏水塘TN、TP平均值分别为1.37 mg/L和0.17 mg/L;自然河溪水质TN、TP的平均值分别为2.91 mg/L和0.18 mg/L;游览水道TN、TP平均值分别为1.91 mg/L和0.09 mg/L;②湿地水体富营养化程度时间变化显著.西溪湿地水质的春季富营养化程度小于夏季,总体处于中度富营养化状态;③不同功能湿地水体富营养化程度差异明显.水塘水体富营养化程度低于河溪富营养化程度,其中,自然水塘水质的富营养化程度低于观赏水塘的水质,相反,游览河溪水质富营养化程度低于自然河溪的水质.因此,加强对观赏水塘和自然河溪的管理,是提高西溪湿地水质的有效方法.

Characteristics of Temporal and Spatial Distribution of Water Quality in Urban Wetland of the Xixi National Wetland Park, China

As the first national wetland park and the representatively urban wetland, Xixi wetland must provide the services of tourism and recreation especially. Based on the data which had been collected monthly from March to August in 2009, the objectives of this paper were to describe the characteristics of water quality in temporally and spatially. The results indicated that: (1) the characteristics of water quality in spatially are significantly corrected with the function of wetland. Total nitrogen (TN) and total phosphorus (TP) average concentrations are 0.78 mg/L and 0.07 mg/L respectively in natural ponds, while the concentrations of TN and TP in ornamental ponds are 1.37 mg/L and 0.17 mg/L respectively. The concentrations of TN and TP are 2.91 mg/L and 0.18 mg/L in natural streams and 1.91 mg/L and 0.09 mg/L in sight-seeing streams; (2) the nutrition in Xixi wetland is different in temporally. The nutrition in Xixi is at the level of moderate eutrophication, while the nutrition is higher in summer than it in spring; (3) the level of eutrophication in pounds is lower than it in streams, of which the level of eutrophication in natural ponds is lower than it in ornamental ponds and the level of eutrophication in natural streams is higher than it in sight-seeing streams by contraries. In order to improve water quality in Xixi wetland, the valid measure is to strengthen the management of ornamental ponds and natural streams.