北京市园林主要灌木单株耗水量比较研究

采用盆栽法分别对6种北京城市常用园林灌木单株的耗水规律进行研究,并对苗木在不同灌溉量处理下的耗水特性及生长表现进行研究与评价。研究结果表明:在相同自然环境条件下,6种灌木的耗水特性划分为三类:高耗水型、低耗水型、中间型。大叶黄杨(Euonymus japonicus)为高耗水型灌木,金银木(Lonicera maackii)、红瑞木(Swida alba)为低耗水型灌木,小叶黄杨(Buxus microphylla)、冬青卫矛(Euonymus kiautschovicus)、棣堂(Kerria ja-ponica)等3种灌木为耗水量适中的灌木类型;不同灌溉处理对6种灌木植物蒸腾耗水量具有显著的影响(P<0.001),随着水分胁迫的加强,6种灌木的蒸腾耗水量表现出依次减少的趋势;选取植物光合速率与单片叶面积作为衡量植物水分匮缺的两项重要指标,其中植物光合速率与灌溉量成线性相关,灌溉量越高植物光合速率越大;不同灌溉处理下的植株基本表现为灌溉量越多,植株外形越好,其中叶面积与灌溉水平之间表现明显的相关性,是体现植株水分匮缺的一个很好的指标。

Contrastive Research on Single Plant Water-consumption Quantity of Main Landscape Shrub in Beijing

Single plant water consumption rules and growth performances under different irrigation conditions of six kinds of landscape shrub in Beijing,namely Euonymus japonicus,Lonicera maacki,Swida alba,Buxus microphylla,Euonymus kiautschovicus and Kerria japonica,were studied by means of potted weighing method.The result showed that according to water consumption quantity,the six kinds could be divided into three categories,namely high water consumption type,low water consumption type and middle water consumption type.Euonymus japonicus was high-water consumption type,Lonicera maackii and Swida alba were low water consumption type,Buxus microphylla,Euonymus kiautschovicus and Kerria japonica were middle water consumption type.Different irrigation treatment had significant influence on the water consumption quantity of the six kinds,as P<0.001.The water consumption quantity of the six kinds showed ordinal decrease tendency with the increase of drought stress.Two indexes,namely plant photosynthesis rate and leaf area,could be selected to evaluate plant water lacking degree.Plant photosynthesis rate had linear relation with irrigation water quantity.The more irrigation water quantity was,the larger plant photosynthesis rate was and the better plant shape was.Leaf area showed significant correlation with irrigation level.So it also was a good index to reflect the plant water lacking degree.