基于SHAW模型对拉萨河谷冬小麦农田生态系统水分传输特征的模拟研究  

Simulation of the water transfer processes of winter wheat field ecosystem using SHAW in Lhasa river valley

作　　者：尹志芳[1,2] 欧阳华[1] 徐兴良[1] 张宪洲[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院研究生院,北京100049

出　　处：《生态学报》2009年第4期2010-2019,共10页Acta Ecologica Sinica

基　　金：国家重点基础研究发展计划(973)资助项目(2005CB422005);国家重大基础研究前期研究专项资助项目(2005CCA05500)

摘　　要：以青藏高原的拉萨河谷下游的农田为研究对象,利用中国科学院拉萨高原生态试验站的观测数据,通过模型模拟的方法分析了高原冬小麦农田生态系统水分传输的主要特征并结合当地的气象条件和灌溉情况对当地制定适宜的冬小麦农田灌溉制度进行了初步探讨。采用2004年5～10月的土壤水分观测数据对SHAW模型进行参数率定,然后,利用2004年10月～2005年10月的土壤水分观测数据对率定的参数进行验证并评价SHAW模型的在该地区的模拟性能。通过分析2004～2005年冬小麦农田水分传输过程的模拟结果,得出该地区农田生态系统水分传输的主要特征:①拔节-灌浆期是冬小麦耗水旺期,水分主要在土壤-植物间传输。②冬小麦生长期间耗水量为826mm,是华北平原的1.7～1.9倍,其中土壤蒸发占了37.5%。③冬小麦根系吸水主要集中于10～40cm土层,在浅层土壤水分供应不足时,冬小麦才倾向于利用深层土壤水分(40cm以下)。④整个冬小麦生长期间农田的总深层渗漏量达到约占总灌溉量的50%。其中,播种-返青期间灌溉量的72%渗漏到70cm土层以下。最后,基于研究得出的冬小麦农田生态系统水分传输特征,对该地区适宜的灌溉制度进行了分析探讨。Water transfer among atmosphere,vegetation,and soil ecosystems is very important in hydrology and ecology;However,there is very few study on this aspect for high land.Based on the experiments and climatic data of Lhasa Plateau Ecosystem Research Station,this paper used SHAW model to investigate the mechanism and characteristic of water transfer in Lhasa river valley on the Tibetan Plateau.The data from May to Oct.in 2004 were used to calibrate the parameters of SHAW model.Then,the calibrated parameters were used to validate the model.Finally,the model was evaluated by estimating soil moisture using the data from Oct.2004 to Oct.2005.Seasonal variations of evaporation,transpiration,soil water content,root extraction and deep percolation during the whole winter wheat growth period of 2004-2005 were analyzed.Major results are reported as follows：①Shooting-Grain filling is the key water consumed stage during the course of winter wheat growth.Water transfer mainly occurred between soil and roots.②The total water-consumption of winter wheat is estimated to be 826 mm,it is about 1.7-1.9 times more than those reported in North China Plain.Hereinto,soil evaporation accounts for 37.5%.③ The roots of winter wheat in this region mainly extract water from 10 to 40cm soil depth,only when 10-40cm soil water is deficiency,winter wheat tends to extract water from deeper soil water（below 40cm）.④During the course of winter wheat growth,total water seepage accounts for 50% of the total irrigation.In particular,two times irrigation in seed-Reviving stage,about 72% irrigation seeped down to 70cm soil.At the end,this paper also discussed the prospective of the suitable irrigation scheduling based on the results of this research on water transfer character.

关 键 词：拉萨河谷 冬小麦 水分传输 SHAW模型 

分 类 号：S512.11[农业科学—作物学]