水源涵养林林木耗水称重法试验研究

Experiment of Water Consumption of Water Conservation Forest by Weighing Methods

为在水源涵养林林木培育中选择耗水量较低的树种 ,在北京密云水库水源涵养林集水区 ,采用小型蒸渗系统测定仪和TDR等仪器 ,用称重法研究了 6个野外水源涵养林树种的耗水特性 ,对 6个树种的日平均耗水进行了比较 ,对不同天气情况下各树种的耗水特性进行了比较。在正常水分条件下 ,各树种的日耗水量 ,从小到大依次为荆条 (Vitexnegundovar.heterophylla)、油松 (Pinustabulaeformis)、臭椿 (Ailanthusaltissima)、侧柏 (Platycladusoriental is)、杨树 (Populussp .)、刺槐 (Robiniapseudoacacia) ;6年生荆条在 7— 9月份平均日耗水量为 0 2 8kg,7年生油松在7— 9月份平均日耗水量为 0 5 7kg,3年生臭椿在 7— 9月份平均日耗水量为 0 5 5kg ,7年生侧柏在 7— 9月份平均日耗水量为 0 7kg,3年生杨树在 7— 9月份平均日耗水量为 0 77kg ,5年生刺槐在 7— 9月份平均日耗水量为 0 78kg。结果表明 ,荆条、臭椿和油松是耗水较少树种 ,适合在水源涵养林中应用。

In order to select low water consumption vegetation species in cultivating the water conservation forest, the apparatus of lysimeter and TDR etc. are used in basin of water conservation in MiYun reservoir in Beijing. The water consumption characteristics are studied through comparison of average water consumption per day and consumption characteristics in different weather of six species with weighing methods. The results showed that in natural moisture condition, the water consumption per day of different species from min to max is Vitex negundovar, Pinus tabulaeformis, Ailanthus altissima, Platycladus orientalis , Poplar, Robinia pseudoacacia . In terms of average water consumption per day from July to September, Vitex negundo var. heterophylla living six years is 0 28?kg, Pinus tabulaeformis living seven years is 0 57?kg, Ailanthus altissima of living years is 0 55?kg, Platycladus orientalis living seven years is 0 7?kg, Poplar living three years is 0 77?kg, Robinia pseudoacacia living five years is 0 78?kg. The results indicated that Vitex negundo var. heterophylla and Pinus tabulaeformis are adapt to be cultivated in water conservation forest because of low water consumption.