黄土高原旱塬区土壤贮水量对冬小麦产量的影响  

Influence of water storage capacity on yield of winter wheat in dry farming area in the Loess Plateau

作　　者：邓振镛[1] 张强[2] 王强[2] 张谋草 王润元[1] 倾继祖[1] 王鹤龄[1] 徐金芳 

机构地区：[1]中国气象局兰州干旱气象研究所甘肃省(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]甘肃省气象局,兰州730020 [3]西峰农业气象试验站,西峰745000 [4]甘肃省气象信息中心,兰州730020

出　　处：《生态学报》2011年第18期5281-5290,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金重点资助项目(40830957);国家科技部公益行业专项资助项目(GYHY200806021;GYHY201106029);2009年中国气象局气候变化专项资助项目(CCSF-09-14);甘肃省科技支撑计划资助项目(090NKCA118);甘肃省科学基金项目(0803RJZA092)

摘　　要：选择黄土高原旱塬区最具代表性的董志塬所在地西峰站冬小麦2 m土层20 a土壤贮水量与产量资料,从大气降水-土壤水-作物循环系统的理论观点出发,研究土壤贮水量对冬小麦产量的影响。结果表明:土壤贮水量减少是旱塬区现代气候暖干化的重要特征,冬小麦生长年度2 m土层土壤贮水量历年平均值为351 mm,总体变化呈下降趋势,每10 a约减少21.4 mm,生长关键阶段的拔节期和孕穗-开花期变化最大,每10 a约减少32.1 mm和54.2 mm;而秋季底墒和返青期变化较平缓,每10 a约减少12.2 mm和7.6 mm,愈往生殖生长阶段干旱出现频率愈大。土壤贮水量突变年与气候产量突变年均发生在1994—1995年。不孕小穗率和千粒重与产量的相关性非常密切,是影响产量的主要要素。不孕小穗率对土壤贮水量的反应尤为敏感,其次是千粒重,最小是穗粒数。不同生育期2 m土壤贮水量与千粒重均呈正相关,其中拔节期与千粒重呈极显著直线相关,每增加10 mm千粒重提高0.8 g,当土壤贮水量在320—500 mm时,千粒重≥30 g,出现频率为80%。土壤贮水量是影响产量最重要的因素,拔节期2 m土壤贮水量与气候产量关系最密切。苗期主要利用浅层土壤水,营养生长中后期至生殖生长阶段主要利用中层和深层土壤水,而且愈往生长后期所利用的土层愈有加深的趋势。在产量形成过程中,不同深度土壤贮水量均起到重要作用,但浅中层(50 cm至1 m)具有突出作用;生殖生长阶段深层(2 m)土壤水向浅中层输送,对产量形成起重要的"补偿作用"。秋季底墒和返青至拔节期土壤贮水量是冬小麦需水和供水矛盾最突出的时期,对产量影响最显著。土壤贮水量对冬小麦产量贡献非常显著,产量年际波动主要受土壤贮水量的影响,气候变干前后的土壤贮水对产量的贡献不同,变干前平均气候产量为604.4 kg/hm2,变干后平均气候产量为-154.2 kg/hm2,下降The Dongzhi loess tableland where the Xifeng Agrometeorological Experimental Station is situated was considered the most representative site of Loess Plateau.By using the data of water storage capacity in 200 cm soil and wheat yield collected by that station during the recent 20 years,we analyzed the influence of water storage capacity in deep soil layers on yield based on the air precipitation-soil moisture-plant（ASP） recycle system theory.The results showed that the reducing trend of soil water storage capacity was linked to climate drying and warming.The average soil water storage capacity was 351mm and was reduced by 21.4 mm every ten years.During critical wheat growth periods such as jointing,and booting to flowering,the soil water storage reduced further by 32.1 mm and 54.2 mm respectively.During autumn and reviving period,the soil water slightly reduced by 12.2 mm and 7.6 mm respectively.The frequency of drought increased when approaching and during reproductive period.The turning point year of climate drying and abnormal climatic yield was from 1994 to 1995.Spike sterility rate and thousand kernel weight（TKW） are the main factors affecting yield.A close relationship among these factors was found.Spike sterility rate was most sensitive to soil water storage,followed by TKW,and grain number per spike is the least.The soil water storage and TKW showed positive correlation in every growth period.A linear correlation was found during bolting period and an increase of storage capacity by 10mm in 200cm soil was correlated with a 0.8g increase in TKW.When the soil water storage was maintained between 320 mm and 500 mm,the frequency of TKW≥30g was 80%.Soil water storage is the most important factor affecting yield.The water storage of 200 cm soil at jointing stage is closely related to climate yield.Wheat plants utilized water from shallow soil layer at seedling stage,and middle to deep layer water at vegetative to reproductive growth stage.The later the growth period,the deeper the soil water was utiliz

关 键 词：黄土高原 旱塬区 土壤贮水量 冬小麦产量 影响 

分 类 号：S512.11[农业科学—作物学]