辽河流域水质状况及其对土地利用/覆被变化的响应

Water Quality in Liaohe River Basin and Its Response to Land Use and Land Cover Change

为了分析辽河流域水环境物理化学变量与土地利用变化的关系,于2009年8月和2010年6月,对辽河流域内80个点位的水环境物理化学特征进行了调查,并对其理化指标进行了综合评价。结果表明,浑河和太子河上游区域水体污染较小,中下游区域水体指标大多为Ⅴ类和劣Ⅴ类;西拉木伦河和老哈河在水域的西北方,水质总体评价为Ⅳ—Ⅴ类,水质情况较差;东辽河流域区域特征不明显,2009年大部分水体指标为劣Ⅴ类,2010年大部分水体指标为Ⅲ到劣Ⅴ类;西辽河流域内大部分河段长期干涸;大辽河流域的地理位置位于整个流域的中东部,水体各项指标大多为Ⅴ类和劣Ⅴ类。相关分析和回归分析表明流域尺度上林地和农田对水体水质参数的浓度影响最大,是影响化学需氧量(CODMn)、含沙量、总氮和电导率(EC)浓度的主要土地利用类型。草地对2009年水质的综合评价结果具有显著正效应。

A total of 80 sampling sites were selected in the Liaohe River basin. During the period of 2009- 2010, physical-chemical variables were analyzed to facilitate comprehensive water quality assessment and in particular to address its relationship with land use/cover. The results indicated that physical and chemical properties showed apparent spatial heterogeneity in the basin. As located in the southeast, little pollution was imposed on Taizihe River and Hunhe River, where water quality in downstream reaching level of V or slightly lower than V. Xilamulunhe River and Laohahe River, located in the northwest of the basin, had water quality ranging between IV and V. There were no obvious features in the East Liaohe River basin, where water quality in downstream was classified as worse than V level in 2009 and was ranging between ]]I and V in 2010. The majority of West Liaohe River was dry for many years. Big Liaohe River basin was loca- ted in middle and eastern, with water quality varied around V. Correlation and regression analysis indicated that forest and agriculture were the major land use types in the watershed scale affecting water quality variables including CODMn, sediment, conductivity and TN. Grassland showed positive effect significantly on the comprehensive water quality in 2009.