极端干旱区3种植物液流特征及其对环境因子的响应  

Sap Flow Characteristics of Three Plant Species and Their Responses to Environmental Factors in an Extremely Arid Region

作　　者：张利刚[1,2,3] 曾凡江[1,3] 刘镇[1,2,3] 刘波[1,2,3] 安桂香[1,2,3] 袁娜[4] 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]中国科学院研究生院,北京100049 [3]新疆策勒荒漠草地生态系统国家野外科学观测研究站,新疆策勒848300 [4]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《干旱区研究》2013年第1期115-121,共7页Arid Zone Research

基　　金：自治区科技重大专项(201130106-1);国家科技支撑计划项目(2009BAC54B05)资助

摘　　要：运用热平衡法包裹式茎流计,对塔克拉玛干沙漠南缘地区优势植物种梭梭(Haloxylon ammodendron)、头状沙拐枣(Calligonum caput-medusae)和疏叶骆驼刺(Alhagi sparsifolia)(以下简称骆驼刺)生长季茎干液流速率变化规律进行持续观测。利用自动气象站对气象因子如太阳辐射(Rs)、气温(Ta)、相对湿度(RH)以及风速进行同步观测,并对气象因子与不同植物液流速率之间的相关关系进行分析。结果表明:①梭梭液流速率日变化趋势为双峰或多峰型,表现出明显的"午休"现象,而头状沙拐枣呈单峰或多峰型,骆驼刺则表现为单峰型,两者均没有明显的"午休"现象;头状沙拐枣与骆驼刺液流启动时间比梭梭延后1 h左右,却提前1 h左右到达液流峰值,液流速率下降时间基本一致;②整个生长季中,梭梭单枝液流量均保持较高水平,在7月达到最大值,而头状沙拐枣和骆驼刺则在8月时达到最大值;③3种植物在不同天气条件下液流速率大小依次为:晴天>沙尘暴>阴天>雨天;④3种植物液流速率与太阳辐射(Rs)、空气温度(Ta)和空气水汽压差(VPD)呈极显著的正相关(P<0.01),与空气相对湿度的关系则表现为极显著的负相关(P<0.01)。Haloxylon ammodendron,Calligonum caput-medusae and Alhagi sparsifolia Shap.are all the dominant species in extremely arid region in the south marginal zone of the Taklimakan Desert in northwest China.These species can be planted in wind break and sand-fixation forest at the desert-oasis ecotone.In this extremely arid region,the mean annual precipitation is 35.1 mm only,the mean annual evaporation is as high as 2 595.3 mm,and average wind speed is 1.9 m·s-1.Growth of H.ammodendron,C.caput-medusae and A.sparsifolia depends highly on snowmelt from the Kunlun Mountains or/and groundwater.In order to explore the water consumption of these three plant species,the values of their sap flow were measured every 10 minutes during the period from June to November with a heat balance Dynamax packaged sap flow measuring system.Moreover,some meteorological factors including solar radiation（Rs）,air temperature（Ta）,air relative humidity（RH） and wind speed were synchronously measured by an automatic weather station.The correlations between sap flow rate and meteorological factors were analyzed.The result are as follows：（1） The data of sap flow under sunny weather were calculated every 30 minutes during July 13-18,the daily curve of sap flow of H.ammodendron was bimodal or multi-peaked,and there was a significant noon depression of sap flow;that of C.caput-medusae was unimodal or multi-peaked,that of A.sparsifolia Shap was unimodal,and there was no obvious noon depression of sap flow neither for C.caput-medusae nor for A.sparsifolia Shap.The starting time and peak value occurrence of sap flow of C.caput-medusae and A.sparsifolia Shap were delayed about 1 hour than that of H.ammodendron,and the time of sap flow rate reduction of the three plant species was similar;（2） In whole growing season,the average monthly values of sap flow flux during the period from June to November were calculated.The result are that the value of H.ammodendron was high all along,and it reached its peak in July,the values of C.caput-me

关 键 词：热平衡法 气象因子 植物茎干液流 液流速率 策勒 塔克拉玛干沙漠 

分 类 号：Q945[生物学—植物学]