CO_2浓度增加对半干旱区春小麦生产和水分利用效率的影响  

Effects of elevated CO_2 concentration on production and water use efficiency of spring wheat in semi-arid area

作　　者：张凯[1,2] 王润元[1] 李巧珍[3] 王鹤龄 赵鸿[1] 阳伏林[1] 赵福年[1] 齐月[1] ZHANG Kai;WANG Run-yuan;LI Qiao-zhen;WANG He-ling;ZHAO Hong;YANG Fu-lin;ZHAO Fu-nian;QI Yue(Institute of Arid Meteorology,China Meteorological Administration/Gansu Province Key Laboratory of Arid Climatic Change and Disaster Reduction/China Meteorological Administration Key Open Laboratory of Arid Climatic Change and Disaster Reduction,Lanzhou 730020,China;Dingxi Arid Meteorology and Ecological Environment Field Experimental Station,China Meteorological Administration,Dingxi 743000,Gansu,China;Dingxi Bureau of Meteorology,Dingxi 743000,Gansu,China）.)

机构地区：[1]中国气象局兰州干旱气象研究所/甘肃省干旱气候变化与减灾重点实验室/中国气象局干旱气候变化与减灾重点开放实验室,兰州730020 [2]中国气象局定西干旱气象与生态环境野外试验基地,甘肃定西743000 [3]甘肃省定西市气象局,甘肃定西743000

出　　处：《应用生态学报》2018年第9期2959-2969,共11页Chinese Journal of Applied Ecology

基　　金：国家公益性行业(气象)科研专项(GYHY201106029;GYHY201506001-2);甘肃省气象局气象科研项目(GSMAMs2016-14);国家自然科学基金项目(41775107;41775105;41575149);干旱气象科学研究基金项目(IAM201505)资助~~

摘　　要：为了解CO_2浓度升高条件下春小麦生产和水分利用效率(WUE)的响应特征,在典型半干旱区定西,利用开顶式气室(OTC)试验平台开展了CO_2浓度增加模拟试验.试验设对照(390μmol·mol^(-1))、480μmol·mol^(-1)和570μmol·mol^(-1)3个CO_2浓度.结果表明:CO_2浓度升高使春小麦冠层空气温度小幅上升,10 cm深处的土壤环境温度下降;CO_2浓度增加对春小麦各器官生物量和总生物量都有明显促进作用,在480和570μmol·mol^(-1)浓度下,地上干物质量平均增长20.6%和41.5%,总干物质量平均增长19.3%和39.6%.生物量增加主要是由茎叶干物质量增加所致,与生育中期物质生产能力明显增强有关;在两种CO_2浓度处理下,植株根冠比分别降低7.3%和11.8%,CO_2浓度增加对春小麦地上部分干物质积累的贡献大于地下部分;CO_2浓度升高主要通过影响穗粒数来影响最终产量,在480和570μmol·mol^(-1)浓度下,小麦产量分别增加了8.9%和19.9%;大气CO_2浓度升高对春小麦光合作用影响的长期效应不明显,随CO_2浓度升高,光合速率显著提高,蒸腾速率降低,蒸发蒸腾量减小.随CO_2浓度升高,叶片、群体和产量3个水平的WUE都增加,其中群体水平的WUE增幅最大,产量水平的WUE增幅最小.In the present study, the response of spring wheat production and water use efficiency（WUE） to the elevated CO2 concentrations was investigated based on the open-top chamber（OTC） experiment platform in Dingxi, a typical semi-arid area. Three different CO2 concentrations（390 μmol·mol^-1, 480 μmol·mol^-1 and 570 μmol·mol^-1） were involved. The results showed that theair temperature above plant canopy increased and the soil temperature at depth of 10 cm decreasedby elevated CO2. The increased CO2 concentration substantially enhanced the total and each component biomass. The aboveground dry mass under the increased CO2 concentrations（480 and 570 μmol·mol^-1） was increased by 20. 6% and 41. 5%, respectively, and the total dry mass was increased by 19. 3% and 39. 6%, respectively. The biomass enhacement was mainly due to the increases of dry mass of stems and leaves, which was strongly related to the material production capacity during the middle growth stage. The root/shoot ratio under the increased CO2 concentrations（480 and 570 μmol·mol^-1） was decreased by 7.3% and 11.8%, respectively, indicating that the elevated CO2 affected the dry matter accumulation of aboveground more than that of below-ground. The yields of spring wheat under the increased CO2 concentrations（ 480 and 570μmol·mol^-1） were higher than that of the control by 8.9% and 19.9%, respectively, mainly dueto the increase of grains per spike. The long-term effect of elevated CO2 concentration on the photo-synthesis of spring wheat was not obvious. The photosynthetic rate significantly increased, the transpiration rate decreased and the evapotranspiration reduced with the increases of CO2 concentration.WUE at the leaf, population, and yield levels increased under elevated CO2 concentration, with the increase range of WUE being the largest at the population level and the lowest at the yield level.

关 键 词：CO2浓度增加 春小麦 生产 水分利用效率 半干旱区 

分 类 号：S512.12[农业科学—作物学]