【作者】 车文瑞；

【导师】 马履一；

【作者基本信息】 北京林业大学 ， 森林培育， 2008， 硕士

【摘要】 本文着眼于北京市水资源短缺但绿地养护需要消耗大量水分的热点问题,在研究和掌握了北京市35种常用园林植物耗水规律的基础上,首次将其耗水量进行时间和空间尺度的扩展,对北京城区绿地(东城区、西城区、朝阳区、海淀区、崇文区、丰台区、宣武区、石景山区)主要植被的年耗水量进行了估算,为制定科学合理的城市绿地灌溉制度、提高城市绿地水分利用效率提供了理论依据。论文按照树种(草种)对绿地耗水量进行估算,分三大类进行:乔木、灌木、草坪。乔木详细估算了13个树种,油松、侧柏2个常绿乔木和国槐等11个落叶乔木,其余常绿和落叶树种采用同类树种耗水量的平均值。通过将树种不同径阶单株年耗水量扩展到北京城区各树种实有植株,实现乔木树种耗水量估算。其中,不同径阶单株年耗水量求算分两种方法进行:①胸径–耗水量模型,②树种单位叶面积年耗水量结合叶面积回归模型。而树种实有植株径阶分布状况,则通过抽样调查、统计分析得到样本径阶分布规律,再将该规律扩展到北京城区乔木实有植株。将不同径阶单株年耗水量,扩展到径阶内所有植株,再将各径阶实有植株年耗水量逐一累加,可实现树种年耗水量的估算,通过计算可得北京城区实有乔木树种年耗水量为3.3亿吨。灌木详细估算了17个树种,分三部分进行:常绿灌木、落叶灌木和绿篱色块。然而,灌木树种耗水量估算需要解决2个核心问题:单位叶面积年耗水量和实有植株叶面积的求算。单位叶面积的年耗水量可通过盆栽试验测定和查阅参考文献获得,实有植株叶面积的求算则需将单株灌木的叶面积扩展到该灌木树种的实有植株。其中,单株叶面积求算分两种情况:①丁香等12个落叶灌木树种,采用叶面积回归模型,②绿球和绿篱,绿面面积(冠表面积)通过几何体表面积计算公式求算,叶面积则通过引入绿面叶面积指数进行转换。叶面积的扩展通过调查灌木不同栽植方式的株型分布规律实现,首先求算某一株型内单株的叶面积,再将单株叶面积扩展到该株型内实有植株的叶面积,最后对树种各株型的叶面积进行累加,就可将灌木树种的实有植株数转换成实有总叶面积。通过上述方法,对常绿灌木、落叶灌木和绿篱色块的实有植株年耗水量分别进行了计算,最后将这3种类型灌木的计算结果进行累加,可知北京城区主要灌木树种年耗水量为23,191,407吨,约0.23亿吨。草坪通过测定高羊茅、草地早熟禾、黑麦草、结缕草、野牛草等5个北京常见草种单位草坪面积年耗水量,再将其扩展到各草种草坪的实有面积,则可求算出北京城区草坪年耗水量为0.36亿吨。结合乔木、灌木、草坪各自的年耗水量,可知北京城区绿地主要植被年耗水量为3.89亿吨,论文所估算的植被包括北京城区99.98%的乔灌木植株和89.98%的草坪面积。北京市年总用水量为34.8亿吨,其中,环境用水4.7亿吨,论文所估算的绿地植被年需水总量,为全市水资源总量的12.4%,全市环境总用水量的82.77%,可见,北京城区绿地每年需消耗大量的水资源。本课题对北京城区绿地主要乔灌草的年耗水量进行了估算,可用于指导园林绿地水分管理,在掌握年度气象信息、乔木树种径阶分布规律和灌木株型分布规律的基础上,可用于预测未来绿地需水情况。更多还原

【Abstract】 This study focused on the outstanding problem between the water scarcity and consuming in greenland maintaining of Beijing. The method used in space and time scaling up was firstly adopted in water utilization which was based on the research of 35 commonly used planting species in Beijing, mainly included 8 districts: Dongcheng District, Xicheng District, Chaoyang District, Haidian District, Chongwen District, Fengtai District, Xuanwu District, Shijingshan District. The estimate of annual water utilization by the mainly vegetation in Beijing provided a theory for establishing the scientific irrigation system and improving the efficiency of water using. Vegetation has divided into 3 types when estimated the water utilization, arbor, shrub, grass.Arbor2 evergreen tree species (Pinus tabulaeformis, Platycladus orientalis) and 11 broad-leaved species has estimated in detail. Other arbors’estimating were used the mean value with their own homologous species. The method for calculated total arbor water utilization was that expanded each species individual tree’s water utilization in different diametric class into the actual numbers. There are two methods to calculated the individual tree water utilization, 1) DBH-water utilization model, 2) regression model used water utilization per unit leaf area. Distribution rule of the arbor in different diametric class was investigated by sampling survey and statistical analysis, then expanded to the whole area in Beijing. Different species’amount of the annual water utilization was cumulated according to this rule: individual tree in different diametric class, all trees in same diametric class, all diametric class. 0.33 billion tons water was consumed by all arbores in each year.ShrubThere shrub was divided into three types in estimating water utilization: evergreen-shrub, deciduous shrub, hedge. Two primary problems should been solved in the estimation: annual water utilization per unit leaf area and the amount of the leaf area in each shrub. Method to solved the first problem was used pot cultivation experiment and referring to some others’research. The second problem was solved by calculated each shrub’s leaf area and then expanded to the whole amount of the shrub species. Two way were used to compute the leaf area, 1) leaf area regression model for deciduous shrub, 2) geometrical equations for global shrub and hedge to calculated the surface area, then convert the area to unit leaf area used leaf area index. Ways of leaf area extension was investigated the different planting methods which shrub commonly used. Firstly, leaf area of individual shrub was calculated, then expanded to all shrubs used the same planting method, at last cumulated all shrub’s leaf in all planting methods. In this way, all the three types shrub’s annual water utilization could be calculated separately. 23 million tons water was consumed by all shrubs in each year.GrassFive grass species’water utilization were measured in per unit area and expanded to the whole area in Beijing. 36 million tons water was consumed by the grass.At last, the amount of water utilization by arbor, shrub and grass could be calculated. 0.389 billion tons water were consumed by these three vegetations, all arbores except ancient trees, all shrubs and all lawn except ground cover plant. Tolally amount of annual water utilization in Beijing are 34.8 billion tons and the amount of environmental water is 4.7 billion tons. Predictive amount of water utilization in this study was 12.4% of tolally amount of annual water utilization, 82.77% of environmental water. So, the Greenland irrigation consumed large numbers of waters.This subject mainly estimated the annual water utilization of Beijing which could be guided the water management and projected the water demand in future which was based on the meteorological information, DBH distribution of ever-green arbors and plant type classification of deciduous shrubs.By reason of not all amount plants were utilized in this study, not involved.更多还原