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1.
全球气候变化直接影响作物生产。玉米是中国种植面积最大的粮食作物，系统探究未来气候变化对其生产力的影响对保障玉米高产稳产和粮食安全具有重要意义。为探究未来气候变化对中国玉米生产力影响，该研究基于SSP1-2.6和SSP5-8.5 共2种气候情景（shared socioeconomic pathways，SSP）1981-2100年逐日气象资料以及中国气象局农业气象观测站玉米生育期数据和土壤数据，使用调参验证后的农业生产系统模拟模型（agricultural production systems simulator，APSIM-Maize）解析了气候变化对中国玉米主产区高产性和稳产性的影响。结果表明：1）未来气候情景下，中国玉米主产区生育期内气温和≥10 ℃有效积温总体呈增加趋势，SSP5-8.5气候情景下升温幅度高于SSP1-2.6气候情景；降水量年际波动大，变化趋势不显著；太阳总辐射呈先增加后减少趋势。2）若不采取适应措施，未来气候变化使玉米全生育期、营养生长期和生殖生长期总体呈缩短趋势，且SSP5-8.5情景下缩短幅度大于SSP1-2.6情景，2080 s缩短幅度大于2030 s和2050 s。3）无适应措施条件下，未来气候变化下研究区域玉米光温潜在产量和雨养潜在产量总体呈下降趋势，SSP5-8.5情景下较SSP1-2.6情景下减产效应更大，2个情景光温潜在产量减产率平均值分别为13.8%和11.9%，雨养潜在产量减产率平均值分别为17.5%和14.0%。玉米潜在产量的稳定性略有提高，但区域间存在差异。因此，未来气候变化使中国玉米生产力总体下降，稳定性略有提高。研究为未来玉米高产稳产和中国玉米种植区划提供理论依据。 相似文献
2.
基于CERES模型的临沂小麦生产的适应措施研究 总被引：6，自引：0，他引：6
采用英国Had ley中心的区域气候模式PREC IS结合CERES-W heat模型,对2071-2100年（2080 s）SRES A2、B2两种排放情景下山东临沂地区小麦生产进行模拟。结果表明：在PREC IS预测的2080 s气候变化情景下,不考虑CO2的肥效作用,临沂地区小麦的生育期明显缩短,产量有所下降,且A2情景下产量下降更明显;考虑CO2肥效作用时,能够补偿温度升高带来的负面影响,两种情景下的小麦产量均显著增加。未来如果保持品种和管理措施不变,A2、B2情景下分别将小麦的播期推迟15d、10d后,小麦的生育期将延长,产量将增加;通过品种参数对产量的影响分析,得出未来气候变化情景下应尽量培育穗粒数较多的品种以提高产量;根据现有品种的表现,未来气候变化情景下,临沂地区适当引进偏春性的冬小麦品种,将可能提高产量。总之,将播期推迟,培育穗粒数较大的小麦新品种或引进偏春性的小麦品种可以减小未来气候变化对临沂小麦生产的不利影响。 相似文献
3.
未来气候变化对中国东北三省玉米需水量的影响预测 总被引：14，自引：5，他引：14
为了预测未来气候变化对中国东北三省玉米需水量的影响,该文在对中国东北三省近26 a来玉米生育期内参考作物蒸散量变化及玉米需水量分析的基础上,结合《排放情景特别报告》（Special Report on Emissions Scenarios, SRES）的两种排放情景A2（强调经济发展）和B2（强调可持续发展）预估的未来气候情景,研究探讨了未来气候情景下中国东北三省玉米需水量的变化趋势。结果表明,未来气候变化情景下,东北三省玉米需水量距平百分率大多表现为增加的趋势,最高可增加77.8%,而且不同地理环境及气候差异下,各地空间分布上也不尽相同。A2情景下,到2040年玉米需水量距平百分率平均增加27.2%,到2070年玉米需水量距平百分率平均增加34.5%,到2100年玉米需水量距平百分率平均增加42.9%;B2情景下,到2040年玉米需水量距平百分率平均增加28.6%,到2070年玉米需水量距平百分率平均增加33.3%,到2100年玉米需水量距平百分率平均增加37.3%。可见,未来中国东北三省水资源可能更趋于短缺状况。 相似文献
4.
气候变化对我国主要粮食作物产量的影响及适应措施 总被引：7，自引：0，他引：7
过去几十年气候变化对我国主要粮食作物产量产生了重要影响,为了研究作物产量对气候变化的响应和适应,保障粮食安全,基于国内相关研究文献,分析归纳了研究方法,综述了国内小麦、玉米和水稻等主要粮食作物产量对气候变化的响应和适应,得出如下结论:（1）作物产量对气候变化响应的研究方法主要包括田间试验观测、统计分析和作物模型模拟等方法,其中田间观测法最直观,统计分析法可操作性强、应用最为普遍,作物模型模拟机理性强,可以定量描述气候因子对作物产量的影响,外推效果好;（2）近几十年来,小麦生育期内气温升高和辐射变化使我国北方小麦增产0.9%~12.9%,南方小麦减产1.2%~10.2%;气候变暖对玉米产量贡献率为-41.4%~0.4%;水稻生育期内气温升高和辐射增强有利于东北地区水稻产量增加,增产贡献率为1.01%~3.29%,而辐射减弱对长江流域等南方主要水稻种植区的水稻产量（长江流域晚熟稻除外）产生不利影响;（3）未来气候变化情境下小麦应从延长生殖生长期、增加籽粒数量和提高收获指数等方面培育新品种应对气候变暖对作物产量的不利影响;耐高温和长生殖生长期的玉米品种可以用来应对气温、降水等气候因子的变化;水稻则应选育耐高温品种应对气温和辐射等因子的变化所带来的作物生产上的风险。 相似文献
5.
气候变化条件下中国灌溉面积变化的产量效应 总被引：7，自引：7，他引：0
灌溉可以有效缓解气候变化对粮食生产的不利影响。采用中国不同区域2006-2019年实际灌溉用水量,对4个气候模式(GFDL-ESM2M,Had GEM2-ES,IPSL-CAM5-LR,MIROC5)驱动下的3种作物模型(GEPIC、PEPIC和LPJml)的灌溉用水量进行评估,优选模拟结果较好的前5个模式组合,分析RCP2.6和RCP6.0情景下,2021-2050年中国玉米、水稻、大豆和小麦产量变化,评估灌溉面积扩张的增产效应。结果显示:未来气候变化下,2021-2050年降水量的增加使得中国水稻和大豆以及北方地区玉米和小麦产量均呈现增长趋势,其中东北80%左右的地区和西北70%左右的地区玉米产量将提高0.2～0.8 t/hm~2,东北85%左右的地区水稻和大豆增产幅度分别超过1.0、0.5 t/hm~2,东北90%左右的地区和西北75%左右的地区小麦产量增幅分别介于1.0～2.0、0.5～1.0 t/hm~2之间。降水量的减少使得西南南部地区的玉米和小麦产量均下降0.2 t/hm~2左右。不同区域玉米和小麦的增产效应差异明显,由于北部地区光热条件较差、小麦基础产量较低,使得小麦灌溉增产潜力(1%～11%)以及增产效率((0.12±0.06)kg/m~3)均较高,北部地区小麦的灌溉面积扩张可有效应对气候变化的不利影响。 相似文献
6.
未来气候情景下农牧交错带不同灌溉水平马铃薯产量和水分利用效率 总被引：1，自引：1，他引：0
未来气候变化对农牧交错带不同灌溉水平马铃薯产量和水分利用的影响鲜有研究。该研究基于农牧交错带张北和武川站不同灌溉条件下大田试验数据评估了APSIM-Potato模型的适应性;基于33个全球气候模式(global climate model,GCM)通过统计降尺度方法获得的未来2个气候情景(RCP4.5和RCP8.5)逐日气候数据驱动APSIM-Potato模型,模拟未来气候变化对不同灌溉水平(灌1水、灌2水、灌3水和灌4水)马铃薯产量和水分利用的影响。结果表明:APSIM-Potato模型能够较好地模拟2个站点马铃薯产量和土壤水分动态。2个站点实测产量和模拟产量的相对误差均小于22.6%,实测土壤水分和模拟土壤水分相对均方根误差均小于18.1%。基于33个GCM模拟结果,2030 s、2060 s和2090 s马铃薯生育期温度、CO2浓度、总降水量和总辐射量相比于基准期(1981-2010)均呈增加趋势。相比于基准期灌1水、灌2水、灌3水和灌4水马铃薯产量,张北站和武川站在RCP4.5情景下均有提升,张北站为4.1%~36.2%,武川站为2.5%~13.6%。RCP8.5情景下,2个站点分别提升3.1%~36.8%和3.1%~38.5%。且2个气候情景下均是灌1水情景下马铃薯产量提升最高。2个气候情景下,马铃薯水分利用效率在2030 s-2090 s均呈增加趋势。研究结果表明未来气候变化对农牧交错带地区马铃薯产量和水分利用效率具有积极影响,未来气候情景下该地区更适宜灌溉马铃薯的生产。 相似文献
7.
从柑橘木虱适宜分布的生理机制、气候特性出发,基于1970−2000年气候环境数据和柑橘木虱分布资料,利用最大熵模型（MaxEnt）筛选得到影响柑橘木虱分布的七个关键气候环境因子,包括温度季节性变化标准差、最干月降水量、最冷季降水量、1月平均最高气温、9月平均最高气温、10月平均最高气温和8月平均最低气温。基于关键气候环境因子重构MaxEnt模型,结合CMIP6多模式气候变化情景数据,预估气候变化对柑橘木虱在中国的潜在分布影响。结果表明：CMIP6不同气候预测模式数据对预测柑橘木虱分布结果具有明显影响,其中CanESM5模式下柑橘木虱适生区面积整体最大,BCC-CSM2-MR模式下整体最小,表明单一模式具有较大的不确定性。多模式集合预测显示,2081−2100年柑橘木虱潜在适生区面积将较1970−2000年呈显著增加趋势,增幅从18.8%（SSP126情景）到55.7%（SSP585情景）,与辐射强迫等级呈明显正相关;尤其是潜在高适生区增幅最大,从78.3%（SSP126情景）到177%（SSP585情景）。柑橘木虱适宜分布北界将不断北移,至2081−2100年,北界将到达32°N（SSP126情景下）−37°N（SSP585情景下）,较目前实际发生北界（30°N）向北偏移2°～7°。研究结果表明气候变暖将对柑橘木虱在中国的扩散十分有利,严重威胁中国柑橘产区生态安全,各地特别是目前尚未发现柑橘木虱的地区需提高警惕,加强柑橘黄龙病检疫和防控。 相似文献
8.
为了预测未来气候变化对石羊河流域棉花生产和耗水的影响,该文采用英国Hadley中心的区域气候模式PRECIS并结合COSIM棉花模型,对SRES A2（强调经济发展）和B2（强调可持续发展）2种排放情景下民勤地区的棉花生产和耗水情况进行模拟,并对石羊河流域扩大棉花种植范围的可能性进行了探讨,最后通过调整播期、引进新品种和改变灌溉量等适应措施的提出分析了石羊河流域棉花生产对未来气候变化的响应。结果表明,在PRECIS预测的未来气候变化情景下,到2080s（2071－2100年）民勤地区棉花的生长期明显延长,产量升高,且A2情景下产量高于B2情景,但B2情景下产量的增长速度更快。棉花产量的变异系数减小,种植棉花的风险降低;到2080s民勤棉花的参考作物蒸散量、耗水量和水分利用效率明显提高,棉花生长的用水需求提高,单位水分生产力上升。参考作物蒸散量和耗水量的变异系数增大,棉花受干旱影响的风险加大,水分利用效率变异系数减小,棉花生长的用水效率更稳定;在A2和B2的未来气候情景下,到2080s武威能满足棉花的正常生长,且在A2情景下获得了较高产量,仅从气候变化方面来考虑,未来石羊河流域棉花适宜种植区将扩大, 棉花生产存在一定潜力;当假设其他条件不变时,到2080s,A2情景下适当推迟播期,B2情景下适当提前播期有利于棉花增产。选择早中熟品种替换早熟品种, A2情景下产量明显增加,而B2情景下产量下降,品种的替换存在一定风险。到2080s随着灌溉量的减少棉花产量明显下降,未来如果灌溉量不足、生产用水让位于生态用水将增加石羊河流域棉花生产的风险。 相似文献
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研究气候变更的空间敏感性,将提高对大规模预测水土流失量的精度。2006年美国学者X.C.Zhang在3个温室、3种耕作措施下,模拟2070~2099年气候变化对水土流失的影响。研究结果表明:在种植季节,温度每增长1℃,导致小麦减产10%;CO2累积量每增长50%,产量增加26%;降雨量每减少1%,产量降低0.9%;传统耕作和保土耕作的土壤流失减少了3.8%。根据全部预测结果得知,径流介于-33%~3%,土壤流失介于-33%~0%。来自不同空间的气候预测的平均水土流失的多样性与气候模拟的多样性一致。当全球气候模型具有预测功能时,应在空间分布规律下评估气候的影响;当分布规律未知时,应在多个空间分布下评估气候的影响。由于空间分布的不确定性,预测的影响随之不确定。 相似文献
10.
基于CMIP5模式和SDSM的赣江流域未来气候变化情景预估 总被引：2，自引：0，他引：2
赣江流域未来气候变化预估,对于了解该流域未来水资源的变化、指导流域防洪抗旱和水资源的合理开发利用具有重要意义。为预估该流域未来气候变化,利用1961—2005年赣江流域6个气象站数据、NCEP再分析数据并选择了CMIP5中CanESM2模式下3种排放情景RCP2.6,RCP4.5,RCP8.5,采用SDSM模型研究了赣江流域未来气候变化。结果表明:（1）赣江流域未来温度和降水总体均呈上升趋势。（2）在RCP2.6,RCP4.5,RCP8.5这3种排放情景下赣江流域未来最高气温分别增加1.8,2.1,2.8℃;未来最低气温分别增加1,1.2,1.9℃;未来平均气温分别增加1.5,1.6,2.3℃;3种排放情景下未来温度空间分布都是南高北低,西高东低,并在南北方向呈带状和环状分布。（3）在未来3个时期（2020s,2050s,2080s）、3种排放情景下赣江流域气温呈上升趋势,且6月份增幅最大,2月份增幅最小。（4）在未来3个时期、3种排放情景下,赣江流域未来降水均呈增加的趋势;5—10月降水量均呈现下降趋势,1—4月、11—12月降水量呈现增加趋势;3种情景下的未来降水空间分布基本呈南低北高,在南北方向呈递增趋势。对赣江流域气候要素模拟与预估表明,赣江流域未来气候变化存在降水增加及极端天气事件发生的危险,分析结果可为赣江流域气候变化的水文响应及气候变化的适应性研究提供科学依据。 相似文献
11.
多模式集合模拟气候变化对玉米产量的影响 总被引：2，自引：1，他引：1
气候模式驱动作物模型是气候变化影响评估的主要手段。但是,单一气候模式输出和作物模型的结构差异使得研究结果存在不确定性。多模式集合的概率预估可以有效减少研究结果的不确定性。为此,本文利用1981—2009年东北地区海伦、长岭、本溪3地区农业气象站的历史气象资料和玉米作物数据,分别建立了作物统计模型并验证了APSIM机理模型在研究区域的适用性。在此基础上,与CMIP5在RCP4.5情景下的8个全球模式结合,尝试基于多模式集合评估了未来2010—2039年时段和2040—2069年时段气候变化对玉米产量的可能影响(相对于1976—2005年基准时段)。研究结果表明,APSIM模型对玉米生长发育和产量形成有很好的模拟能力。玉米生育期的模拟误差(RMSE)为3~4 d,产量的RMSE为0.6~0.8 t?hm~(-2)。建立的产量统计模型表明,玉米出苗阶段(5月中旬)的温度增加对产量增加有积极作用,而开花到成熟阶段(7月中旬到9月上旬)的温度和降水的增加、光照的不足均不利于产量增加。与1976—2005年基准时段相比,气候因素影响下2010—2039年玉米产量减少3.8%(海伦)~7.4%(本溪),减产的概率为64%(长岭)~73%(本溪);2040—2069年时段减产6.4%(海伦)~10.5%(本溪),减产的概率为74%(海伦)~83%(本溪)。未来2010—2039年时段和2040—2069年时段基于机理模型模拟的产量降低分别为6.6%(海伦)~8.9%(本溪)和9.7%(海伦)~13.7%(本溪),均高于相应时段基于统计模型得到的0.9%(海伦)~6.0%(本溪)和2.0%(长岭)~7.3%(本溪)减产结果。 相似文献
12.
Thomas Gaiser Michael JudexAttanda Mouinou Igué Heiko PaethClaudia Hiepe 《Agricultural and Forest Meteorology》2011,151(8):1120-1130
In this century climate change is assumed to be the major driver for changes in agricultural systems and crop productivity at the global scale. However, due to spatial differences in cropping systems and in the magnitude of climatic change regional variations of climate change impact are expected. Furthermore, the recent climate projections are highly uncertain for large parts of West Africa. In particular with respect to annual precipitation and variability the projections vary between trends with decreasing precipitation and trends with slightly increasing precipitation within the next decades. On the other hand, the extensive fallow systems in this region suffer from increasing population pressure, which compromises soil fertility restoration. In the Republic of Benin, the demographic projections for the first half of this century indicate a continuous growth of the population with a narrow interval of confidence. Thus, in the absence of an adequate soil fertility management with judicious use of mineral fertilizers, the soil degradation process with decreasing crop yields is expected to continue. The objective of this paper was, therefore, to quantify the regional effect of future population growth on crop yields in West Africa and to compare it with the potential effects of climate change scenarios. Three land use scenarios (L1, L2 and L3) for the Upper Ouémé catchment where derived from different demographic projections combined with assumptions regarding future road networks and legal frameworks for forest protection using the CLUE-S modeling approach. The fallow-cropland ratio decreased in the three scenarios from 0.87 in the year 2000 to 0.66, 0.48 and 0.68 for L1, L2 and L3, respectively in 2050. Based on the projected ratio of fallow and cropland, trends of maize yield for the three land use scenarios were calculated using the EPIC (Environmental Policy Integrated Climate) model coupled with a spatial database. Maize yields followed the decreasing trend of the fallow-cropland ratio and estimated yield reductions amounted to up to 24% in the period 2021-2050. This trend was compared with the impact of the SRES climate scenarios A1B and B1 based on the output of the GCM ECHAM5 downscaled with the REMO model and the A1B scenario output of the GCM HADC3Q0 downscaled with the RCMs SMHIRCA and HADRM3P. The yield reductions due to the projected climate change in the three models accounted for a yield decrease of up to 18% (REMO A1B scenario) in the same period. Taking into account the smaller uncertainties in the scenario assumptions and in the model output of the land use scenarios, it is concluded that, in low input fallow systems in West Africa, land use effects will be at least as important as climate effects within the next decades. 相似文献
13.
气候模拟数据订正方法在作物气候生产潜力预估中的应用 ——以江苏冬小麦为例 总被引：1，自引：0，他引：1
利用全球气候模式BCC_CSM1.1（Beijing Climate Center Climate System Model version 1.1）,耦合区域气候模式RegCM4（Regional Climate Model version 4）输出的1961-1990年（基准时段）气候模拟数据,并根据同期实测资料,确定模拟值和实测值之间的非线性传递函数与方差订正参数,构建气候模拟数据的误差订正模型。利用1991-2005年（验证时段）模拟数据与实测资料验证该模型的有效性,并对RCP（Representative Concentration Pathway）情景下2021-2050年（未来时段）气候模拟数据进行订正,同时通过潜力衰减方法预估未来江苏冬小麦气候生产潜力格局。结果表明：将气候模拟数据订正方法应用到作物气候生产潜力预估是有效的。以均值传递函数和方差信息建立的模型可以较好订正江苏逐日气候模拟数据。订正后的秋冬季气温、辐射量、蒸散量和冬春季降水量模拟偏差明显减小。在此基础上研究发现,冬小麦的成熟期在RCP4.5和RCP8.5情景下介于153~175和153~174,较基准时段均明显提前。两种情景下冬小麦气候生产潜力分别介于10335~14368kg·hm-2和9991~13708kg·hm-2,较基准时段呈下降趋势。其变异系数分别介于7.6%~14.6%和7.5%~13.6%,较基准时段呈增大趋势,表明江苏冬小麦气候生产潜力总体趋于不稳定。未来时段,徐州中北部、连云港东北部、宿迁西部以及盐城东南部冬小麦在RCP4.5和RCP8.5情景下可以保持相对较高的生产潜力（≥12501kg·hm-2）,该省应确保这些地区的冬小麦种植用地。研究建议,作物气候生产潜力预估应考虑利用研究区实测资料对气候模拟数据进行订正,以提高预估可信度。 相似文献
14.
干旱是影响华北地区冬小麦产量的主要农业气象灾害之一,作物生长模型是评估干旱对作物产量影响主要方法之一,但作物生长模型对极端天气气候条件下（如干旱）作物产量模拟效果仍存在不确定性。为提高作物模型在干旱条件下对作物产量模拟的精准性,该研究利用调参验证后的农业生产系统模型（agricultural production systems simulator,APSIM）,通过查阅与华北地区冬小麦相关的186篇大田试验文献获得1 876对观测数据,以作物水分亏缺指数为干旱指标,评估APSIM模型在冬小麦拔节-开花和开花-成熟阶段干旱对产量影响的模拟效果,提出APSIM在拔节-开花和开花-成熟阶段干旱对小麦产量影响的修正系数。基于历史气候条件、SSP245和SSP585未来气候情景资料,分析了冬小麦拔节-开花和开花-成熟阶段干旱时空分布特征,并采用修正系数校正后的APSIM模型评估华北地区冬小麦拔节-开花和开花-成熟阶段不同等级干旱对其产量的影响。结果表明,APSIM模型低估了拔节-开花阶段干旱对冬小麦产量影响程度,轻旱、中旱和重旱校正系数分别为0.85、0.91和0.85;APSIM模型可准确模... 相似文献
15.
Proper spatial and temporal treatments of climate change scenarios projected by General Circulation Models (GCMs) are critical to accurate assessment of climatic impacts on natural resources and ecosystems. The objective of this study was to evaluate the site-specific impacts of climate change on soil erosion and surface hydrology at the Changwu station of Shaanxi, China using a new spatiotemporal downscaling method. The Water Erosion Prediction Project (WEPP) model and climate change scenarios projected by the U.K. Hadley Centre's GCM (HadCM3) under the A2, B2, and GGa emissions scenarios were used in this study. The monthly precipitation and temperature projections were downloaded for the periods of 1900–1999 and 2010–2039 for the grid box containing the Changwu station. Univariate transfer functions were derived by matching probability distributions between station-measured and GCM-projected monthly precipitation and temperature for the 1950–1999 period. The derived functions were used to spatially downscale the GCM monthly projections of 2010–2039 in the grid box to the Changwu station. The downscaled monthly data were further disaggregated to daily weather series using a stochastic weather generator (CLIGEN). The HadCM3 projected that average annual precipitation during 2010–2039 would increase by 4 to 18% at Changwu and that frequency and intensity of large storms would also increase. Under the conventional tillage, simulated percent increases during 2010–2039, compared with the present climate, would be 49–112% for runoff and 31–167% for soil loss. However, simulated soil losses under the conservation tillage during 2010–2039 would be reduced by 39–51% compared with those under the conventional tillage in the present climate. The considerable reduction in soil loss in the conservation tillage indicates the importance of adopting conservation tillage in the region to control soil erosion under climate change. 相似文献
16.
Abstract Mean monthly weather data values from 1968 – 2000 for 12 major rainfed wheat production areas in north-west and western Iran were used with a climate model, United Kingdom Meteorological Organization (UKMO), to predict the impact of climate change on rainfed wheat production for years 2025 and 2050. The crop simulation model, World Food Study (WOFOST, v 7.1), at CO2 concentrations of 425 and 500 ppm and rising air temperature of 2.7 – 4.7°C, projected a significant rainfed wheat yield reduction in 2025 and 2050. Average yield reduction was 18 and 24% for 2025 and 2050, respectively. The yield reduction was related to a rainfall deficit (8.3 – 17.7%) and shortening of the wheat growth period (8 – 36 d). Cultivated land used for rainfed wheat production under the climate change scenarios may be reduced by 15 – 40%. Potential improvements in wheat adaptation for climate change in Iran may include breeding new cultivars and changing agronomic practices like sowing dates. 相似文献
17.
Nasrin Azad Vahid Rezaverdinejad Heydar Tayfeh Rezaie 《Archives of Agronomy and Soil Science》2018,64(5):731-746
In this research, impact of climate change on wheat yield was simulated using SWAP in Myandoab, Iran. Field data of wheat in 2004–2005 and 2005–2006 periods were used for calibration and validation of the SWAP, respectively. The HadCM3 outputs, for A1B, A2 and B1 scenarios and 2046–2065 periods, were used in SWAP and wheat yield in mentioned period was compared with base period. Three irrigation levels, based on meeting 100, 70 and 50% of the crop ET demand, were used to study the climate change effects on wheat yield in full and deficit irrigation conditions. The results showed that temperature and reference evapotranspiration will increase in 2055s. Temperature increase cause to decrease crop growing period and crop evapotranspiration. The results showed that the negative impact of temperature increase has dominated to the positive impact of CO2 concentration and the yield is reduced. For full irrigation situation, the reduction will be 24.1, 22.4 and 20.8% in A1B, A2 and B1, respectively. Reduction in yield can be related to the shorter maturity period of the crop. The results showed that under deficit irrigation, the yield is also decreased but this decrease rate of yield is higher in full irrigation. 相似文献
18.
《CATENA》2010,80(3):237-242
Proper spatial and temporal treatments of climate change scenarios projected by General Circulation Models (GCMs) are critical to accurate assessment of climatic impacts on natural resources and ecosystems. The objective of this study was to evaluate the site-specific impacts of climate change on soil erosion and surface hydrology at the Changwu station of Shaanxi, China using a new spatiotemporal downscaling method. The Water Erosion Prediction Project (WEPP) model and climate change scenarios projected by the U.K. Hadley Centre's GCM (HadCM3) under the A2, B2, and GGa emissions scenarios were used in this study. The monthly precipitation and temperature projections were downloaded for the periods of 1900–1999 and 2010–2039 for the grid box containing the Changwu station. Univariate transfer functions were derived by matching probability distributions between station-measured and GCM-projected monthly precipitation and temperature for the 1950–1999 period. The derived functions were used to spatially downscale the GCM monthly projections of 2010–2039 in the grid box to the Changwu station. The downscaled monthly data were further disaggregated to daily weather series using a stochastic weather generator (CLIGEN). The HadCM3 projected that average annual precipitation during 2010–2039 would increase by 4 to 18% at Changwu and that frequency and intensity of large storms would also increase. Under the conventional tillage, simulated percent increases during 2010–2039, compared with the present climate, would be 49–112% for runoff and 31–167% for soil loss. However, simulated soil losses under the conservation tillage during 2010–2039 would be reduced by 39–51% compared with those under the conventional tillage in the present climate. The considerable reduction in soil loss in the conservation tillage indicates the importance of adopting conservation tillage in the region to control soil erosion under climate change. 相似文献
19.
《Agricultural and Forest Meteorology》2004,121(1-2):113-125
Field experiments with soybean were conducted over a period of 1990–1998 in diverse Indian locations ranging in latitude, longitude, and elevation. These locations provided a wide range of environments for testing and validation of the crop growth (CROPGRO) model considered in this study with observed changes in soils, rainfall and other weather parameters. Model predicted satisfactorily the trends of days to flowering, maturity and grain yields. The deviations of simulated results were within ±15% of the measurements.Validated CROPGRO model has been used to simulate the impact of climate change on soybean production in India. The projected scenarios for the Indian subcontinent as inferred from three state-of-the-art global climate models (GCMs) have been used in the present study. There was a decrease (ranging between about 10 and 20%) in soybean yield in all the three future scenarios when the effect of rise in surface air temperature at the time of the doubling of CO2 concentration was considered. The results obtained on the mitigatory option for reducing the negative impacts of temperature increases indicate that delaying the sowing dates would be favorable for increased soybean yields at all the locations in India. Sowing in the second season would also be able to mitigate the detrimental effects of future increases in surface temperature due to global warming at some locations. 相似文献