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1.
Using seasonal climate forecasts to improve maize production decision support in Zimbabwe 总被引：1，自引：0，他引：1
N. ZinyengereT. Mhizha E. MashonjowaB. Chipindu S. GeertsD. Raes 《Agricultural and Forest Meteorology》2011,151(12):1792-1799
Maize production in marginal tropical regions is at great risk due to rainfall variability and climate change. Climate change is set to increase the variability and uncertainty of inter-annual rainfall. Farmers who depend on rainfed maize production for their livelihoods would therefore benefit from improved climate based forecasting of production likelihood. In this study we developed a simple maize production decision support tool for Masvingo by using seasonal climate forecasts and a crop model to forecast maize yields likelihood prior to the season. We follow up on earlier studies carried out in Zimbabwe which show that the El Nino Southern Oscillation (ENSO) can be used to forecast rainfall and maize yields in Zimbabwe. An ENSO based seasonal climate analysis tool (RAINMAN) was used to produce probabilistic monthly climate forecasts for Masvingo corresponding to the phases of the Southern Oscillation Index (SOI). The climate forecasts were used to run a crop model (AquaCrop) for a variety of scenarios relevant to maize production (monthly rainfall, cultivar selection, planting date, and fertility level). The results of the simulations were similar to those observed by Phillips et al. (1997) and formed the basis for the development of an operational decision support tool. Simulated maize yields varied from 1.2 t/ha to 5.8 t/ha. The simulated yields were higher than expected average yields in a marginal region like Masvingo especially under small holder farming. The work suggested that optimal use of forecasts may lead to improved maize production in Masvingo. The study set a platform for the development of operational climate based maize production decision support tools in Zimbabwe. 相似文献
2.
Global warming due to an anticipated doubling of carbon dioxide concentration in the atmosphere is expected to alter the earth's climate system within the next century. The potential changes in the climate system could affect hydrological cycles and processes. Possible impacts of climate change on water resources should be assessed to evaluate probable adaptation measures. In the Philippines, a preliminary assessment of the vulnerability of water resources to climate change and variability was undertaken. For this particular study, the Angat Reservoir was chosen as the study area. Because of its socioeconomic importance, it is useful to assess its vulnerability to climate change. A rainfall-runoff simulation model, WATBAL, was used to determine the effect of temperature and rainfall changes, based on CO2 doubling, on inflow to the reservoir. Climate change scenarios developed from results from three general circulation models and incremental changes were used. The results showed that changes in temperature and rainfall could affect runoff either positively or negatively. Using the temperature and rainfall changes from the Geophysical Fluid Dynamics Laboratory model there was a 32% increase in runoff, and with the Canadian Climate Centre Model, there was a 15% decrease in runoff. Under a climate scenario generated by the United Kingdom Meteorological Office model, runoff is estimated to increase by 5%. The use of incremental scenarios revealed the strong sensitivity of runoff to changes in rainfall as compared with changes in temperature. 相似文献
3.
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
4.
1962-2010年潜在干旱对中国冬小麦产量影响的模拟分析 总被引：5，自引：3，他引：2
旱灾是冬小麦生产中常见的气象灾害,该研究旨在了解气候变化背景下中国冬小麦小麦受干旱的历史影响及变化情况,这对合理指导冬小麦生产的减灾、防灾,稳定冬小麦产量有重要的指导意义和作用。该研究采用CERES-Wheat模型,模拟了1962-2010年潜在干旱对中国冬小麦产量影响的时空变化趋势,并分析其与大气环流因子间的关系,以期了解中国近50a来冬小麦受旱程度的变化情况。结果表明:1)1962-2010年中国冬小麦因干旱造成的潜在产量损失总体呈上升的趋势,但不同时期表现不同,其中20世纪60年代、20世纪80年代表现为下降趋势。2)在过去近50a里,中国冬小麦潜在旱灾产量损失中心有向西北移动的趋势,这主要是受黄土高原和河西走廊地区受旱程度增强的影响。3)中国冬小麦潜在旱灾产量损失中心的经纬度和影响中国降水的副热带高压、北极涡系统的部分指数具有显著的负相关关系。冬小麦生长季同期(前一年10月-当年5月)的副热带高压系列指数与中心的相关关系表现显著,而生长季同期和生长季前期(前一年6月-前一年9月)的北极涡系列指数与中心都具有显著的相关关系。当冬小麦生长季同期北半球的西太平洋副高、印度副高和南海副高的强度偏强、范围偏大时,潜在旱灾产量损失中心的位置将会偏西;当北极涡在冬小麦生长季前期或同期偏大偏强时,中国冬小麦潜在产量损失中心将偏南,反之亦然。 相似文献
5.
气候变化背景下播期对东北三省春玉米产量的影响 总被引：1，自引：0，他引：1
为探究气候变化背景下东北三省(黑龙江省、吉林省和辽宁省)春玉米适宜播期的变化程度,本文以东北三省春玉米潜在种植区为研究区域,基于1981—2015年气象资料,1981—2012年农业气象观测站玉米生育期、产量资料以及土壤资料,分气侯区对农业生产系统模型(APSIM)进行调参和验证,建立适用于东北三省10个不同气候区的模型相关参数,在各气候区利用调参验证后的APSIM-Maize模型设置不同播期,模拟各年代不同播期下春玉米潜在产量和气候生产潜力,综合高产和稳产性指标,明确了不同区域各年代不同条件下适宜播期范围。研究结果表明,APSIM模型对于东北三省7个春玉米品种开花和成熟两个关键生育期以及产量模拟结果与实测结果具有较好的一致性,表明APSIM模型能够较好地模拟研究区域春玉米生育期和产量。充分灌溉条件下,研究区域内适宜播期范围从4月16日至5月19日,空间上呈纬向分布南早北迟的特征; 20世纪90年代和21世纪00年代玉米适宜播期较20世纪80年代有提前趋势,其中20世纪90年代提前趋势更明显;第1、第3、第5、第7和第9气候区雨养条件下较充分灌溉条件下适宜播期有推迟趋势,推迟天数为3～6 d。雨养条件下各年代不同气候区理论上的适宜播期较目前生产中实际播期下的产量提高2.84%～9.96%。以上结果为进行未来气候变化对东北三省春玉米影响及其适宜播期等研究提供了技术支撑。 相似文献
6.
1961—2010年气候变化对西南冬小麦潜在和
雨养产量影响的模拟分析 总被引：3，自引：3，他引：3
利用农业气象试验站作物资料及土壤资料,评价 APSIM-Wheat 模型在西南地区的适应性,应用该模型分析该地区1961—2010年冬小麦潜在和雨养产量的时空变化特征,通过逐步回归分析揭示小麦生长季主要气象因子对潜在产量和雨养产量的影响及相对贡献率。研究结果表明： APSIM 模型对该区5个常用小麦品种的模拟效果较好,模拟与实测生育期的均方根误差(RMSE)在7.0 d 以内,地上部分生物量和产量模拟值与实测值的归一化均方根误差(NRMSE)均低于25%,模型在西南地区具有较好的适应性。1961—2010年研究区域36%的站点冬小麦生长季总辐射显著降低,其中北部、东南部和南部中区最显著;68%的站点生长季≥0℃有效积温显著增加,西部增温显著;30%的站点生长季平均气温日较差显著减小,南部中区最显著;全区生长季总降水大面积减少但不显著,减少区主要位于最南端和东南部。模拟的冬小麦潜在产量在65%的站点呈显著减产趋势,南部中区和北部变化最明显;雨养产量在25%的站点显著降低,北部地区较明显,全区减产趋势较弱。减产显著的站点中,生长季辐射降低、温度升高、气温日较差减小对潜在产量降低的贡献率分别为45%、36%和2%,对雨养产量降低的贡献率分别为36%、39%和－8%,而降水减少对雨养产量降低的贡献率为7%。西南冬小麦生长季辐射降低、温度升高及降水减少共同导致了冬小麦潜在和雨养产量的显著下降,而气温日较差的降低对冬小麦潜在和雨养产量的影响分别表现为负作用和正作用,整体上辐射和温度的影响程度最大。 相似文献
7.
8.
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
9.
不同时间尺度太阳辐射数据对作物生长模型的影响(英) 总被引：2，自引：1，他引：1
逐日太阳辐射数据是作物模拟模型的重要输入参数之一。然而,在很多情况下,候、旬、月尺度的辐射信息相对容易获取。该文利用长时间序列(1961-2000)逐日太阳辐射数据,分别建立研究区候、旬、月不同时间尺度太阳辐射数据库,利用两个常用的作物生长模型(CERES-Maize和CGOPGRO-Soybean),以逐日数据(太阳辐射和模拟结果)为基准,分别探讨在雨养和灌溉条件下,不同时间尺度太阳辐射数据对作物生长模型的影响。结果表明:在不同时间尺度下,模型的输出(花期和作物产量)都接近于基准值。总体来看,两个模型模拟的花期平均误差和平均相对误差均接近于0,均方根误差为3.5d;CERES-Maize模型的模拟产量低于基准值,而CGOPGRO-Soybean的模拟结果高于基准值。在雨养和灌溉条件下,CERES-Maize的平均相对误差和均方根误差分别为-0.59%,120kg/hm2和-0.52%,129kg/hm2,CGOPGRO-Soybean的平均相对误差和均方根误差分别为5%,152kg/hm2和4.7%,165kg/hm2。短期数据误差(RMSE)是影响模型精度的主要因素。CGOPGRO-Soybean模型对不同时间尺度太阳辐射数据和水情信息比CERES-Maize模型敏感。当缺少逐日太阳辐射数据时,在雨养和灌溉条件下,候、旬、月尺度的太阳辐射数据都可以用于作物生长模型。 相似文献
10.
气温、降水和辐射是农作物生长发育必需的基本气候要素，其大小、波动及空间分布决定局部地区的种植结构和农产品产量增减，具有喜温喜水特性的玉米其生长发育对气候变化的响应更为敏感。本研究基于辽宁省新民和朝阳地区近40a气象数据分析各气候要素变化特征，根据局地气候暖干化趋势耦合气温、降水、辐射三要素构建不同气候情景，利用田间实测数据对WOFOST模型进行校准和适用性检验，并将该模型用于模拟不同气候情景下辽宁典型雨养春玉米产量变化。结果表明：（1）验证后的WOFOST模型能较好地模拟两站点春玉米产量，其模拟值与实测值的相对均方根误差分别为8.78%和5.96%，一致性系数分别为0.82和0.96。（2）新民和朝阳两地在设定的气候要素变化范围内春玉米产量与气温呈负相关，与降水呈正相关。在气温增加，降水减少，辐射增强的不同梯度气候情景下，新民（气温+1.2℃，降水量−25%，辐射+4%）和朝阳（气温+1.4℃，降水量−25%，辐射+3%）减产幅度分别达92.5%和85.9%，接近雨养春玉米绝产的警戒气候情景。（3）新民春玉米产量受降水影响显著，朝阳则对气温变化响应敏感，而两地产量对给定比例的辐射变化均未表现出明显波动。 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.
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
13.
The forest cover of Thailand has been characterized according to the Holdridge Life Zone Classification, a model that correlates climatic features with vegetation distribution. Six Holdridge life zone types of forest cover are found in Thailand: subtropical dry forest, subtropical moist forest, subtropical wet forest, tropical dry forest, tropical moist forest, and tropical wet forest. Climate change scenarios were simulated by three general circulation models: two United Kingdom Meteorological Office models (the low and high resolution versions) and the Goddard Institute for Space Studies model. These scenarios were used to simulate the effects of future climate change on Thai forests. The ratios of precipitation and the absolute values of temperature changes were incorporated into a baseline climate scenario from the International Institute of Applied Systems Analysis. Under the climate change scenarios simulated by the three general circulation models, the subtropical dry forest could potentially disappear, and areas of tropical very dry forest would appear. In general, the area of subtropical life zone would decline from about 50% to 20%–12% of total cover, whereas the tropical life zone would expand its cover from 45% to 80%. All three general circulation model scenarios suggest that the tropical dry forest has the greatest potential to extend into the subtropical moist forest. This analysis suggests that global climate change would have a profound effect on the future distribution and health of Thai forests. 相似文献
14.
利用黄土高原地区西安、兰州、太原、银川、呼和浩特和延安6个气象站1951—1990年的日序列的降雨量、最高温度、最低温度及日照时间,用LARS-WG天气发生器模拟1991—2000年的日气象资料,并用1991—2000年的实际观测值与之比较,对LARS-WG天气发生器适应性进行了检验。通过线性回归、平方根误差和平均偏差评价表明:通过长序列日气象资料,LARS-WG天气发生器能准确地模拟黄土高原6个站点的日最高温度、日最低温度的月分布和年辐射总量。年降水及其月分布值普遍高于实际降水值。 相似文献
15.
《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
16.
A. DaccacheE.K. Weatherhead M.A. StalhamJ.W. Knox 《Agricultural and Forest Meteorology》2011,151(12):1641-1653
The impacts of climate change on the irrigation water requirements and yield of potatoes (Solanum tuberosum L.) grown in England have been assessed, by combining the downscaled outputs from an ensemble of general circulation models (GCM) with a potato crop growth model. The SUBSTOR-Potato model (embedded within the DSSAT program) was used to simulate the baseline and future irrigation needs (mm) and yield (t ha−1) for selected emissions scenario (SRES A1FI and B1) for the 2050s, including CO2 fertilisation effects. The simulated baseline yields were validated against independent experimental and field data using four reference sites. Probabilistic distribution functions and histograms were derived to assess GCM modelling uncertainty on future irrigation needs. Assuming crop husbandry factors are unchanged, farm yields would show only marginal increases (3-6%) due to climate change owing to limitations in nitrogen availability. In contrast, future potential yields, without restrictions in water or fertiliser, are expected to increase by 13-16%. Future average irrigation needs, assuming unconstrained water availability, are predicted to increase by 14-30%, depending on emissions scenario. The present ‘design’ capacity for irrigation infrastructure would fail to meet future peak irrigation needs in nearly 50% of years. Adaptation options for growers to cope with these impacts are discussed. 相似文献
17.
Henrik Eckersten Antje Herrmann Alois Kornher Magnus Halling Erik Sindhøj Elisabet Lewan 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):151-165
Abstract In recent decades European silage maize production has extended northwards, into Scandinavia, and the importance of maize in fodder production has increased substantially. For the northward expansion of maize production it is of interest to evaluate both the role of climate change that has occurred already, and scenarios for possible future climate change. The aim of this study was to assess for Swedish climatic conditions, the annual variation in silage maize yield and quality (dry weight and starch contents) of cultivars currently grown in Germany. The MAISPROQ simulation model currently used in German maize production was applied to evaluate the effects of (i) cultivar differences (four cultivars; four sites; 2003–2009), (ii) intra-regional variation among ten sites representing three regions (two cultivars; 2003–2009), and (iii) climatic variability among two historical periods during 1961–2009 and three future periods during 2011–2100 using A2-emission climate scenarios and the Delta-method (two cultivars; four sites). Forage quality assessments strongly influenced the assessments of harvest time and thereby the yield. Changes in simulated yield of the tested cultivars were high for the past climate, but relatively small under future climatic conditions due to earlier harvest caused by improved forage quality. By the end of the 21st century an appropriate fodder quality would be achieved every year in the south of Sweden, whereas in the middle of Sweden (60°N) about 30% of the years would not be successful, even for the earliest cultivar. In the east, increased water stress counteracted the positive effect of a prolonged growing season. It was concluded that adaptation of field experiments to model calibration requirements remains to be done, in order to enable extrapolation of observations from Swedish field trials to a changing future climate. 相似文献
18.
Impact of climate change on soil erosion, runoff, and wheat productivity in central Oklahoma 总被引：3，自引：1，他引：3
The potential for global climate changes to increase the risk of soil erosion is clear, but the actual damage is not. The objectives of this study were to evaluate the potential impacts of climate change on soil erosion, surface runoff, and wheat productivity in central Oklahoma. Monthly projections were used from the Hadley Centre's general circulation model, HadCM3, using scenarios A2a, B2a, and GGa1 for the periods of 1950–1999 and 2070–2099. Projected changes in monthly precipitation and temperature distributions between the two periods were incorporated into daily weather series by means of a stochastic weather generator (CLIGEN) with its input parameters adjusted to each scenario. The Water Erosion Prediction Project (WEPP) model was run for four climate scenarios including a recent historical climate and three tillage systems (conventional tillage, conservation tillage, and no-till). HadCM3-projected mean annual precipitation during 2070–2099 at El Reno, Oklahoma decreased by 13.6%, 7.2%, and 6.2% for A2a, B2a, and GGa1, respectively; and mean annual temperature increased by 5.7, 4.0, and 4.7 °C, respectively. Predicted average annual soil loss in the tillage systems other than no-till, compared with historical climate (1950–1999), increased by 18–30% for A2a, remained similar for B2a, and increased by 67–82% for GGa1. Predicted soil loss in no-till did not increase in the three scenarios. Predicted mean annual runoff in all three tillage systems increased by 16–25% for A2a, remained similar for B2a, and increased by 6–19% for GGa1. The greater increases in soil loss and runoff in GGa1 were attributed to greater variability in monthly precipitation as projected by HadCM3. The increased variability led to increased frequency of large storms. Small changes in wheat yield, which ranged from a 5% decrease in B2a to a 5% increase in GGa1, were because the adverse effects of the temperature increase on winter wheat growth were largely offset by CO2 rise as well as the bulky decrease in precipitation occurred outside the growing season. The overall results indicate that no-till and conservation tillage systems will be effective in combating soil erosion under projected climates in central Oklahoma. 相似文献
19.
Daniel R. Chavas R. César Izaurralde Allison M. Thomson Xuejie Gao 《Agricultural and Forest Meteorology》2009,149(6-7):1118-1128
Increasing atmospheric greenhouse gas concentrations are expected to induce significant climate change over the next century and beyond, but the impacts on society remain highly uncertain. This work examines potential climate change impacts on the productivity of five major crops in eastern China: canola, corn, potato, rice, and winter wheat. In addition to determining domain-wide trends, the objective is to identify vulnerable and emergent regions under future climate conditions, defined as having a greater than 10% decrease and increase in productivity, respectively. Data from the ICTP RegCM3 regional climate model for baseline (1961–1990) and future (2071–2100) periods under A2 scenario conditions are used as input for the EPIC agro-ecosystem simulation model in the domain [30°N, 108°E] to [42°N, 123°E]. Simulations are performed with and without the enhanced CO2-fertilization effect. Results indicate that aggregate potential productivity (i.e. if the crop is grown everywhere) increases 6.5% for rice, 8.3% for canola, 18.6% for corn, 22.9% for potato, and 24.9% for winter wheat, although with significant spatial variability for each crop. However, without the enhanced CO2-fertilization effect, potential productivity declines in all cases ranging from 2.5 to 12%. Interannual yield variability remains constant or declines in all cases except rice. Climate variables are found to be more significant drivers of simulated yield changes than changes in soil properties, except in the case of potato production in the northwest where the effects of wind erosion are more significant. Overall, in the future period corn and winter wheat benefit significantly in the North China Plain, rice remains dominant in the southeast and emerges in the northeast, potato and corn yields become viable in the northwest, and potato yields suffer in the southwest with no other crop emerging as a clear beneficiary from among those simulated in this study. 相似文献
20.
春季干旱对旱地冬小麦生产的影响及施肥和灌溉的应对效果——以2003年和2009年山西垣曲县冬小麦生产的调查和试验观察为例 总被引：1，自引：0，他引：1
旱灾多发是气候变化中农业生产面临的日益严重的挑战。而干旱半干旱区农业对旱灾表现出明显的脆弱性。本文收集了2009年和2003年山西省垣曲县农业生产调查资料和山西省农业科学院在该县的肥料试验示范地小麦生产试验资料,统计分析了2009年干旱下小麦产量与正常气候年（2003年）对比的变化,表明气候变化下小麦生长期干旱导致大田小麦减产超过30％,并田块间产量变率由正常气候年的10％左右提高到22％-42％。在雨养旱地,施肥技术试验示范地减产幅度在6％以下;干旱年水浇地的增产效果达到48％-64％,而施肥技术的增产效果达到30％-44％。而水浇地优化施肥示范地产量甚至比正常气候年产量提高36％～77％。肥水协调技术大幅度减缓了干旱下产量损失,同时大大降低了田块间产量变率,达到有效抵御干旱对小麦产量的影响。因此,发展优化施肥及肥水协调技术在应对气候变化的影响中具有显著的减缓潜力,而水资源的有效供应可能成为北方气候变化下干旱对旱地作物生产的主要挑战。 相似文献