滇中城市水源地水源涵养能力研究

Study on the Water Conservation Capacity of Urban Catchment Areas in Central Yunnan

水源涵养能力是水源地保护研究的主要内容。基于昆明、玉溪、楚雄3个城市水源地内的中和、大矣资、马家庄和凤屯(二)站1982—2011年实测流量数据,通过总径流和基流的变化来揭示水源涵养能力的时空变化规律,并依据MODIS,Landsat遥感影像分析其主要影响因素。结果显示:总径流和基流均为凤屯(二)站最大,马家庄站最小,两站分别相差48%,70%;1982—2011年,总径流和基流除大矣资站呈显著下降趋势(α≥99.6%)外,其余站变化趋势不显著;总径流和基流与降水量、林地面积比率呈较好正相关(R2≥0.814 4),与园地面积比率呈负相关(R2=0.687 7),与植被覆盖率、耕地面积比率相关性不明显(R2≤0.379 8)。可见九龙甸水库的水源涵养能力最强,东风水库最弱;松华坝水库、九龙甸水库和东风水库的九溪河流域的水源涵养能力无显著的变化趋势,东风水库的董炳河流域呈显著减弱的趋势;水源涵养能力随降水量、林地面积增大而增强,随园地面积增大而减弱,植被覆盖率的大小不能反映水源涵养能力的强弱。

Water conservation capacity is the main aspect of water source area protect.Therefore,based on the precipitation and runoff date of Zhonghe,Dayizi,Majiazhuang and Fengtun（Ⅱ）from 1982 to 2011in Kunming,Yuxi and Chuxiong,MODIS and Landsat remote sensing image,the space-time characteristics and the influence of precipitation,vegetation coverage and land use type were analyzed.The results showed that the total runoff and base flow in Fengtun（Ⅱ）were maximum,and were minimum in Majiazhuang,the different of the two stations were 48% and 70%,respectively.The total runoff and base flow in Dayizi declined significantly（α≥99.6%）,the trend of the other station was not significant from 1982 to 2011.The total runoff and base flow had positive linear correlation with precipitation,forest land area ratio（R^2≥0.814 4）,had negative with garden area ratio（R^2=0.687 7）,but had no correlation with vegetation coverage,the cultivated land area ratio（R^2≤0.379 8）.The study showed that the water conservation capacity was the strongest in Jiulongdian and the weakest in Dongfeng.The ability of water conservation had not significant change in Jiulongdian,Songhuaba and Jiuxihe of Dongfeng,but had significantly declined in Dongbinghe of Dongfeng.The increase of precipitation and forest area will be conducive to source self-restraint ability enhancement,the increase of the future area will lead to a drop in water conservation ability,but the vegetation coverage can not reflect the level of water conservation capacity.