北方城市森林建设典型灌木树种蒸腾耗水特征

Transpiration characters of five typical shrubs for unban forestation

节水型城市森林绿化建设是水资源短缺地区城市生态建设必须重视的问题之一。文中以位于我国北方大连市中心劳动公园内五种主要灌木树种大叶黄杨、连翘、木槿、丁香及女贞为研究对象采用渗漏式蒸渗仪法对其耗水量进行研究,根据水量平衡的原理,分析蒸渗仪中土壤储水量、渗水量和植物蒸散量的水分动态变化。同时对比了不同季节各灌木树种的日耗水量从而确定其耗水类型。结果表明:各种植物对土壤水分都有不同程度的消耗,其中连翘和丁香的土壤储水变化较小,空白较大;土壤渗水量与降雨量关系密切,较大的降雨,使土壤瞬时的持水力下降,造成较多的水分渗漏,渗漏量最大的为空白池,其余依次为丁香、大叶黄杨、连翘、木槿、女贞;对不同季节各灌木日耗水量的比较对其进行耗水类型的分类,可以将各种植物分为3类:女贞为春季耗水型植物,大叶黄杨和丁香为夏季耗水型植物,连翘和木槿为秋季耗水型植物。

Water - efficient urban aforestation is one of the issues that should be pay more attention for the cities located in the water resources shortage area. This research took 5 main species Euonymus japonicus, Forsythia suspense, Hibiscus syriacus ,Ligustrum lucidum and Syringa oblate as the subjects. They are growing in the Labor Park, Dalian city. Drainage lysimeters were used to study the plant water consumption. According to the principle that water balance, the soil water content, leakage and the plant evaporation in the drainage lysimeters were analyzed. Meanwhile, the daily water consumption and its consumption type of the shrubs in different seasons were compared too. The results were as follows： different plants have different water consumption. The soil water storage diversification of Forsythia suspense and Ligustrum lucidum are less than others, and the check plot is more. There is a strong relationship between the rainfall and the leakage. The check plot has the biggest leakage and the following sequences are Ligustrum lucidum, Euonymus japonicus, Forsythia suspense, Hibiscus syriacus, Syringa oblate. According to the shrubs daily water consumption, the consumption of these plants can be divided into 3 types： Syringa oblate is the Spring water consumption type, Euonymus japonicus and Ligustrum lucidum are the Summer water consumption type, Forsythia suspens and Hibiscus syriacus are the Autumn water consumption type.