沙漠-绿洲过渡带2种典型灌丛滞尘能力研究

Evaluation of Dust-retention Ability of Two Typical Shrubs in Ulanbuh Desert-oasis Ecotone

【目的】开展沙漠-绿洲过渡带天然灌丛滞尘研究,为区域防风固沙树种选择与配置和绿洲防护体系建设提供依据。【方法】通过野外调查、采集叶片和室内水洗过滤,对乌兰布和沙漠-绿洲过渡带2种阔叶灌木(白刺和沙冬青)的叶片滞尘量进行了研究。【结果】结果表明:从绿洲到沙漠,2种灌丛变小、植株变矮、枝条和叶片数量减少、叶面积变小。同一样地中,白刺单叶和单位叶面积滞尘量均显著低于沙冬青(P<0.01),而白刺灌丛单丛叶片滞尘量与单个样方内灌丛总滞尘量均显著高于沙冬青灌丛(P<0.01)。从绿洲到沙漠,2种灌丛的单叶滞尘量和单位叶面积滞尘量均表现出明显增加趋势。【结论】不同样地条件影响灌丛滞尘量;同一样地条件下由于2种灌丛植物体特征、叶片特征存在差异而使2者的滞尘能力差异显著。

【Objective】Research on dust-retention of natural shrub in desert-oasis ecotone was carried out,which provided basis for selection and allocation of regional wind-proof and sand-fixing tree species and construction of oasis protection system.【Method】The amount of dust-retention of two species of broadleaf shrubs(Nitraria tangutorum and Ammopiptanthus mongolicus)were tested and analyzed using field sampling and water filtering method in Ulanbuh desert-oasis ecotone.【Result】Plant growth gradually weakened from oasis to desert.In the same field,the dust-retention ability of single leaf and unit leaf area of N.tangutorum were significantly lower than that of A.mongolicus.However,the dust-retention ability per tree of A.mongolicus were significantly higher than N.tangutorum.The dust-retention ability of single leaf and unit leaf area of N.tangutorum and A.mongolicus gradually increased from oasis to desert.【Conclusion】The natural shrubs have the strong ability to reduce dust content.The dust-retention of shrub was affected by environmental conditions,and two different shrubs have distinctly different dust detaining abilities when in the same dust environment.