不同CO_2浓度变化下干旱对冬小麦叶面积指数的影响差异  

The difference of drought impacts on winter wheat leaf area index under different CO_2 concentration

作　　者：李小涵[1,2] 武建军[1,2] 吕爱锋[3] 刘明[1,2] 

机构地区：[1]北京师范大学减灾与应急管理研究院,北京100875 [2]地表过程与资源生态国家重点实验室,北京100875 [3]中国科学院地理科学与资源研究所,北京100101

出　　处：《生态学报》2013年第9期2936-2943,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(NSFC41171403);国家科技支撑计划课题(2012BAH29B02);长江学者和创新团队发展计划资助(PCSIRT)

摘　　要：叶面积指数是作物生长状况的一个重要表征参数,也是研究陆地生态系统的一个重要的参数。当今世界温室气体排放逐年上升,气候变暖趋势明显,对气候变化敏感的农业将受到影响。在全球变化的背景下,采用农业技术转移决策支持系统(DSSAT)系统,通过在黄淮海平原典型站点模拟3种CO2浓度条件下冬小麦在水分充足和水分亏缺2种情境下的生长过程,分析不同CO2浓度下水分亏缺对冬小麦叶面积指数的影响差异。研究发现,CO2浓度升高对叶面积指数增长有促进作用,且在干旱情况下对叶面积指数的正效应比湿润情况下更为明显,在CO2浓度倍增条件下,发生水分亏缺的作物叶面积指数数倍增长。研究结论有助于分析CO2浓度变化对农作物生长过程的影响,为农田水分管理提供依据,又为估算叶面积指数提出了一种模型的方法。The leaf area index(LAI) controls a variety of biophysical and physiological processes of vegetation canopy,such as photosynthesis,respiration,transpiration,carbon cycle,precipitation interception and energy exchange,thus it is an important parameter for characterizing crop growth as well as studying terrestrial ecosystems.In recent years,with the continuous increase of greenhouse gas emissions,the whole globe has gone through an intensifying warming trend.Up to now,a large number of agricultural experiments,such as Free Air CO2 Enrichment,(FACE) and Open-Top-Chamber(OTC),show that elevated CO2 concentration will cause reduced plant transpiration rate,strengthened stomatal resistance and a significant increase in water use efficiency.Agriculture,which is quite sensitive to climate change,will be significantly affected under the context of global warming.In this paper,the Decision Support System for Agrotechnology Transfer(DSSAT) developed by the U.S.Department of Agriculture is used to simulate the growth process of winter wheat under three different CO2 concentrations combined with water deficiency and adequacy status.The observed experimental data over 2007—2008 is from Gucheng Ecology and Agricultural Experiment Station,Chinese Academy of Meteorological Sciences.Using DSSAT,the impacts of environmental CO2 concentration change on crop LAI are analyzed.The results indicate that elevated CO2 concentration will strengthen the leaf area index growth,with more significant positive effects on LAI under drought condition(water supply:150mm) than under the wet condition(water supply: 620mm),At current CO2 level,crop LAI under water deficiency condition is significantly less than that under wet condition;when the CO2 concentration is increased by 20%,the difference of LAI under dry and wet conditions declined slightly;when the CO2 concentration is doubled,the maximum of LAI under wet conditions increased by 0.31 and LAI under the water deficiency increased by 0.82,which leads to the conclusion that crop LAI under wat

关 键 词：CO2浓度 叶面积指数 冬小麦 干旱 DSSAT 

分 类 号：S512.11[农业科学—作物学]