玛纳斯河流域荒漠植被单株茎干液流及光合蒸腾特性研究

Study of Liquid Flow and the Characteristics of Photosynthesis and Transpiration of Vegetation Plant Stems in Manasi River Basin

植物茎干液流量可表征其蒸腾耗水量,反映植被水分传输状况,可用于计算植被生态需水量。以玛纳斯河流域古尔班通古特沙漠南缘典型荒漠植被梭梭、柽柳为研究对象,通过数据监测,研究植被茎干液流及光合蒸腾特性,分析气象因子及土壤含水率对茎干液流的影响。结果表明:梭梭、柽柳茎干液流速率呈明显的昼夜变化规律,白天液流速率远高于夜间;梭梭的净光合速率日变化模式为双峰型,柽柳为单峰型;梭梭蒸腾速率的日变化有明显上升和下降过程,柽柳趋势不明显,呈小幅震荡;液流速率变化与相对空气湿度呈负相关,空气湿度高时液流速率低;气温、总辐射与液流速率的变化趋势基本一致,液流速率随着气温或总辐射的增强而增大;随着土壤含水率降低,液流速率降低。

Plant stem sap flow of water consumption ,that reflects the status of vegetation water transmission ,and determines the vegetation ecological water requirement .Research＇s study objectn is Haloxylon ammodendron and Tamarix vegetation that in the southern Gurbantunggut Desert of Manasi River Basin ,Through the data monitoring to research the liquid flow and the characteris-tics of photosynthesis and transpiration of vegetation stem ,and analysis of the effect on the stem sap flow of meteorological factors and soil moisture content .The results show that ：Haloxylon ammodendron and Tamarix stem sap flow rate showed a significant di-urnal variation ,the flow rate is much higher than the night .Changes in net photosynthetic rate of Haloxylon ammodendron mode light of day is shuangfeng type and Tamarix chinensis belong to Single peak type .Diurnal changes of transpiration rate of Haloxylon ammodendron had the obvious rise and fall ,but Tamarix tendency is not obviously .The liquid flow rate was negatively correlated with relative humidity of the air ,and the change trend of temperature ,radiation and the liquid flow rate is basically the same .Along with the soil water content decreased ,the liquid flow rate decreased .