共查询到20条相似文献，搜索用时 31 毫秒
1.
利用随机天气模型, 将气候模式对大气中CO2倍增时预测的气候情景与CERES-小麦模式相连接, 研究了气候变化对我国冬小麦和春小麦生产的可能影响.结果表明, 气候变化后小麦发育将加快, 生育期缩短, 冬小麦平均缩短7.3天, 春小麦平均缩短10.5天, 春小麦生育期缩短的绝对数和相对数均大于冬小麦.籽粒产量呈下降趋势, 冬小麦平均减产7%~8%, 雨养条件下比水分适宜时减产幅度略大.春小麦的减产幅度大于冬小麦, 水分适宜时平均减产17.7%, 雨养时平均减产31.4%. 相似文献
2.
Climate change impact assessment: the role of climate extremes in crop yield simulation 总被引：6，自引：2，他引：4
This work was aimed at assessing the role of climate extremes in climate change impact assessment of typical winter and summer Mediterranean crops by using Regional Circulation Model (RCM) outputs as drivers of a modified version of the CropSyst model. More specifically, climate change effects were investigated on sunflower (Helianthus annuus L.) and winter wheat (Triticum aestivum L.) development and yield under the A2 and B2 scenarios of the IPCC Special Report on Emissions Scenarios (SRES). The direct impact of extreme climate events (i.e. heat stress at anthesis stage) was also included. The increase in both mean temperatures and temperature extremes under A2 and B2 scenarios (2071?C2100) resulted in: a general advancement of the main phenological stages, shortening of the growing season and an increase in the frequency of heat stress during anthesis with respect to the baseline (1961?C1990). The potential impact of these changes on crop yields was evaluated. It was found that winter and summer crops may possess a different fitting capacity to climate change. Sunflower, cultivated in the southern regions of the Mediterranean countries, was more prone to the direct effect of heat stress at anthesis and drought during its growing cycle. These factors resulted in severe yield reduction. In contrast, the lower frequency of heat stress and drought allowed the winter wheat crop to attain increased yields with respect to the baseline period. It can be concluded that the impact of extreme events should be included in crop-modelling approaches, otherwise there is the risk of underestimating crop yield losses, which in turn would result in the application of incorrect policies for coping with climate change. 相似文献
3.
The water deficits in different development stages and the whole growing season of winterwheat in North China under climate change scenarios are analyzed based on the meteorological da-ta,crop phenomenon and soil hydrological data of 30 weather stations.The results show that ifthe temperature rises,the potential evapotranspiration and crop maximum transpiration will in-crease 8%-10%;the actual evapotranspiration in whole growing season will increase about 1%-2%;and it seems to decrease in spring.Therefore the water deficit status would deteriorate.Theamount of water deficit in whole growing season would increase 14%-30%,and the water deficitisolines might shift southward with maximum shift distance being 190 km.As a result the climaticsuitability of winter wheat would change,and the variation rate of yield reduction will be 8%-20% of the present value which results in the declining output values.The irrigation amountwould increase 25%-33%,and the agriculture cost might increase owing to additional irrigation. 相似文献
4.
Ellen J. Cooter Michael B. Richman Peter J. Lamb David A. Sampson 《Climatic change》2000,44(1-2):89-121
A regional database containing historical time series and climate change scenarios for the Southeastern United States was developed for the U.S.D.A. Forest Service Southern Global Change Program (SGCP). Daily historical values of maximum temperature, minimum temperature and precipitation and empirically derived estimates of vapor pressure deficit and solar radiation across a uniform 1° latitude × 1° longitude grid were obtained. Climate change scenarios of temperature, precipitation, vapor pressure deficit and solar radiation were generated using semi-empirical techniques which combined historical time series and simulation field summaries from GISS, GFDL, OSU and UKMO General Circulation Model (GCM) experiments. An internally consistent 1° latitude × 1° longitude climate change scenario database was produced in which vapor pressure deficit and solar radiation conditions were driven by the GCM temperature projections, but were not constrained to agree with GCM calculated radiation and humidity fields. Some of the unique characteristics of the database were illustrated through a case study featuring growing season and annual potential evapotranspiration (ETp) estimates. Overall, the unconstrained scenarios produced smaller median ETp changes from historical baseline conditions, with a smaller range of outcomes than those driven by GCM-directed scenarios. Collectively, the range of annual and growing season ET changes from baseline estimates in response to the unconstrained climate scenarios was +10% to +40%. No outlier responses were identified. ETp changes driven by GCM-directed (constrained) UKMO radiation and humidity scenarios were on the order of +100%, resulting in the identification of some ETp responses as statistical outliers. These response differences were attributed to differences between the constrained and unconstrained humidity scenarios. 相似文献
5.
气候变化可能不会引起我国北方冬小麦营养品质下降 总被引：1，自引：0，他引：1
为了探索未来气候变化对冬小麦营养品质的影响,采用开顶式气室与红外辐射器相结合的方法开展了冬小麦生长季增温和CO2浓度升高的复合影响试验,在6个小麦生长季模拟了21世纪中后期两种可能的增温和CO2浓度升高情景。结果表明,在生长季增温与CO2浓度升高情景下,冬小麦冬后发育期前移,生育期平均气温较对照的增加幅度远小于生长季增温幅度,灌浆期遭遇的高温日数减少,主要生育阶段的平均太阳辐射强度减弱。在增温与CO2浓度升高复合影响下,冬小麦籽粒蛋白质含量略有增加,籽粒淀粉与脂肪含量未显示规律性的变化趋势,增温对小麦蛋白质含量的综合影响弥补了CO2浓度升高对籽粒蛋白质含量的负效应。如果不考虑小麦品种变化影响,预计未来气候变化可能不会导致我国北方冬小麦籽粒营养品质下降。 相似文献
6.
Vulnerability and adaptation assessments of agriculturalcrops under climate change in the Southeastern USA 总被引：1，自引：0，他引：1
Summary It is expected that a change in climatic conditions due to global warming will directly impact agricultural production. Most
climate change studies have been applied at very large scales, in which regions were represented by only one or two weather
stations, which were mainly located at airports of major cities. The objective of this study was to determine the potential
impact of climate change at a local level, taking into account weather data recorded at remote locations. Daily weather data
for a 30-year period were obtained for more than 500 sites, representing the southeastern region of the USA. Climate change
scenarios, using transient and equilibrium global circulation models (GCM), were defined, created and applied to the daily
historical weather data. The modified temperature, precipitation and solar radiation databases corresponding to each of the
climate change scenarios were used to run the CERES v.3.5 simulation model for maize and winter wheat and the CROPGRO v.3.5
model for soybean and peanut. The GCM scenarios projected a shorter duration of the crop-growing season. Under the current
level of CO2, the GCM scenarios projected a decrease of crop yields in the 2020s. When the direct effects of CO2 were assumed in the study, the scenarios resulted in an increase in soybean and peanut yield. Under equilibrium , the GCM climate change scenarios projected a decrease of maize and winter wheat yield. The indirect effects of climate change
also tended to decrease soybean and peanut yield. However, when the direct effects of CO2 were included, most of the scenarios resulted in an increase in legume yields. Possible changes in sowing data, hybrids and
cultivar selection, and fertilization were considered as adaptation options to mitigate the potential negative impact of potential
warming.
Received July 20, 1999/Revised April 18, 2000 相似文献
7.
Assessing Winter Wheat Responses to Climate Change Scenarios: A Simulation Study in the U.S. Great Plains 总被引：3，自引：0，他引：3
Hard red winter wheat (Triticum aestivum L.) is a major crop in the Great Plains region of the U.S. The goal of this assessment effort was to investigate the influence of two contrasting global climate change projections (U.K. Hadley Center for Climate Prediction and Research and Canadian Centre for Climate Modelling and Analysis) on the yield and percent kernel nitrogen content of winter wheat at three locations in Nebraska. These three locations represent sub-humid and semi arid areas and the transition between these areas and are also representative of major portions of the winter wheat growing areas of the central Great Plains. Climate scenarios based on each of the projections for each location were developed using the LARS-WG weather generator along with data from automated weather stations. CERES-Wheat was used to simulate the responses for two contrasting cultivars of wheat using two sowing dates. The first sowing date represented current sowing dates appropriate for each location. The second sowing date was later and represents the approximate date when the mean air temperature from the climate scenarios is the same as the mean air temperature from the actual climate data at the current sowing dates. The yield and percent kernel nitrogen content using the two climate scenarios generally decrease going from the sub-humid eastern to the semi arid western parts of Nebraska. Results from these simulations indicate that yield and percent kernel nitrogen content using the two climate scenarios could not both be maintained at levels currently simulated. Protein content (directly related to kernel nitrogen content) and end-use quality are the primary determinants for the use of hard red winter wheat in baked goods. Nitrogen management and new cultivars, which can enhance the uptake and translocation of nitrogen, will be proactive steps to meet the challenges of global climate change as represented by these climate scenarios. 相似文献
8.
Climate Change Impacts on the Potential Productivity of Corn and Winter Wheat in Their Primary United States Growing Regions 总被引：2，自引：0，他引：2
We calculate the impacts of climate effects inferred from three atmospheric general circulation models (GCMs) at three levels of climate change severity associated with change in global mean temperature (GMT) of 1.0, 2.5 and 5.0 °C and three levels of atmospheric CO2 concentration ([CO2]) – 365 (no CO2 fertilization effect), 560 and 750 ppm – on the potential production of dryland winter wheat (Triticum aestivum L.) and corn (Zea mays L.) for the primary (current) U.S. growing regions of each crop. This analysis is a subset of the Global Change Assessment Model (GCAM) which has the goal of integrating the linkages and feedbacks among human activities and resulting greenhouse gas emissions, changes in atmospheric composition and resulting climate change, and impacts on terrestrial systems. A set of representative farms was designed for each of the primary production regions studied and the Erosion Productivity Impact Calculator (EPIC) was used to simulate crop response to climate change. The GCMs applied were the Goddard Institute of Space Studies (GISS), the United Kingdom Meteorological Transient (UKTR) and the Australian Bureau of Meteorological Research Center (BMRC), each regionalized by means of a scenario generator (SCENGEN). The GISS scenarios have the least impact on corn and wheat production, reducing national potential production for corn by 6% and wheat by 7% at a GMT of 2.5 °C and no CO2 fertilization effect; the UKTR scenario had the most severe impact on wheat, reducing production by 18% under the same conditions; BMRC had the greatest negative impact on corn, reducing production by 20%. A GMT increase of 1.0°C marginally decreased corn and wheat production. Increasing GMT had a detrimental impact on both corn and wheat production, with wheat production suffering the greatest losses. Decreases for wheat production at GMT 5.0 and [CO2] = 365 ppm range from 36% for the GISS to 76% for the UKTR scenario. Increases in atmospheric [CO2] had a positive impact on both corn and wheat production. AT GMT 1.0, an increase in [CO2] to 560 ppm resulted in a net increase in corn and wheat production above baseline levels (from 18 to 29% for wheat and 2 to 5% for corn). Increases in [CO2] help to offset yield reductions at higher GMT levels; in most cases, however, these increases are not sufficient to return crop production to baseline levels. 相似文献
9.
基于温度、降水、光照等指标,通过利用区域气候模式所预估的分辨率为1°(纬度)×1°(经度)的未来气候预估数据,对1981~2005年的基准期和RCP4.5、RCP8.5两排放情景下2069~2098年中国热量资源以及冬小麦种植界限、理论生育期和气候适宜种植分区的空间分布特征进行了对比分析。研究主要结论为:与基准期相比,两未来气候变化情景下我国热量资源、冬小麦种植条件与气候适宜性差异显著。且相比于RCP4.5情景,在RCP8.5情景下中国2069~2098年多数地区热量资源增加、冬小麦种植北界和南界北移东扩、可种植面积扩大,多数区域理论适宜播种期推迟、理论成熟期提前、潜在生长季缩短,且潜在生长季内的光—温—水配置使得冬小麦气候适宜性有所提高。但由于冬小麦为喜凉作物,对高温胁迫非常敏感,RCP8.5情景下更多的极端高温天气和不对称增温等因素带来的负面影响很可能抵消前述光—温—水配置所带来的有利影响,从而降低冬小麦的种植适宜性。因此,未来研究工作仍应致力于减缓气候变化,以保障我国粮食生产的安全。 相似文献
10.
11.
The study used a daily step conceptual hydrological model to examine the effects of climate change on snowfall accumulation and on snow cover melting in the Broye catchment (moderate relief- altitude from 400 to 1500 m a.s.l.). Five elevation bands representing a range of climatic conditions were used together with three realistic climate change scenarios based loosely on GCM's predictions and which reflect feasible changes by extending time periods. For a very moderate climate change (rise in air temperature of ca 1 °C), possibly in a near future, the reduction of snow cover duration, mean water equivalent and monthly maximum water equivalent is the most sensitive in the lower part of the catchment and during the first and last months of the snow season. In the higher part of the basin and during the colder months January and February, similar reduction rates can be expected in case of larger climate changes. The floods due to the melting of snow cover are lower. Sometimes rainfall, considered as snow in the present day conditions, generates additional floods during the winter season. For winter sports resorts below 1500 m a.s.l., even the very moderate climatic change scenario (temperature rise around 1 °C) leads to economically very difficult conditions. Finally, a climatic change detection index based on snow cover duration is proposed. 相似文献
12.
J. E. Olesen T. R. Carter C. H. Díaz-Ambrona S. Fronzek T. Heidmann T. Hickler T. Holt M. I. Minguez P. Morales J. P. Palutikof M. Quemada M. Ruiz-Ramos G. H. Rubæk F. Sau B. Smith M. T. Sykes 《Climatic change》2007,81(1):123-143
The uncertainties and sources of variation in projected impacts of climate change on agriculture and terrestrial ecosystems depend not only on the emission scenarios and climate models used for projecting future climates, but also on the impact models used, and the local soil and climatic conditions of the managed or unmanaged ecosystems under study. We addressed these uncertainties by applying different impact models at site, regional and continental scales, and by separating the variation in simulated relative changes in ecosystem performance into the different sources of uncertainty and variation using analyses of variance. The crop and ecosystem models used output from a range of global and regional climate models (GCMs and RCMs) projecting climate change over Europe between 1961–1990 and 2071–2100 under the IPCC SRES scenarios. The projected impacts on productivity of crops and ecosystems included the direct effects of increased CO2 concentration on photosynthesis. The variation in simulated results attributed to differences between the climate models were, in all cases, smaller than the variation attributed to either emission scenarios or local conditions. The methods used for applying the climate model outputs played a larger role than the choice of the GCM or RCM. The thermal suitability for grain maize cultivation in Europe was estimated to expand by 30–50% across all SRES emissions scenarios. Strong increases in net primary productivity (NPP) (35–54%) were projected in northern European ecosystems as a result of a longer growing season and higher CO2 concentrations. Changing water balance dominated the projected responses of southern European ecosystems, with NPP declining or increasing only slightly relative to present-day conditions. Both site and continental scale models showed large increases in yield of rain-fed winter wheat for northern Europe, with smaller increases or even decreases in southern Europe. Site-based, regional and continental scale models showed large spatial variations in the response of nitrate leaching from winter wheat cultivation to projected climate change due to strong interactions with soils and climate. The variation in simulated impacts was smaller between scenarios based on RCMs nested within the same GCM than between scenarios based on different GCMs or between emission scenarios. 相似文献
13.
Winter wheat is one of China’s most important staple food crops, and its production is strongly influenced by weather, especially droughts. As a result, the impact of drought on the production of winter wheat is associated with the food security of China. Simulations of future climate for scenarios A2 and A1B provided by GFDL-CM2, MPI_ECHAM5, MRI_CGCM2, NCAR_CCSM3, and UKMO_HADCM3 during 2001-2100 are used to project the influence of drought on winter wheat yields in North China. Winter wheat yields are simulated using the crop model WOFOST (WOrld FOod STudies). Future changes in temperature and precipitation are analyzed. Temperature is projected to increase by 3.9-5.5 for scenario A2 and by 2.9-5.1 for scenario A1B, with fairly large interannual variability. Mean precipitation during the growing season is projected to increase by 16.7 and 8.6 mm (10 yr)-1 , with spring precipitation increasing by 9.3 and 4.8 mm (10 yr)-1 from 2012-2100 for scenarios A2 and A1B, respectively. For the next 10-30 years (2012-2040), neither the growing season precipitation nor the spring precipitation over North China is projected to increase by either scenario. Assuming constant winter wheat varieties and agricultural practices, the influence of drought induced by short rain on winter wheat yields in North China is simulated using the WOFOST crop model. The drought index is projected to decrease by 9.7% according to scenario A2 and by 10.3% according to scenario A1B during 2012-2100. This indicates that the drought influence on winter wheat yields may be relieved over that period by projected increases in rain and temperature as well as changes in the growth stage of winter wheat. However, drought may be more severe in the near future, as indicated by the results for the next 10-30 years. 相似文献
14.
灌溉是河南省冬小麦最重要的种植管理模式。在DSSAT-CERES小麦模型参数调试和区域适用性验证的基础上,利用区域气候模式PRECIS输出的未来气候情景资料,量化分析了2021—2050年河南省灌溉条件下冬小麦产量的可能变化,结果表明:若不采取其他措施,未来A2,B2两种温室气体排放情景下,河南省冬小麦产量平均减少5%左右,A2情景减产率略高于B2;随着产量降低,产量波动区间略有缩小,但25%~75%的稳产区间也相应缩小,且B2情景下更容易出现极端低产的年份;冬小麦水分利用效率相应降低。采取适当应对措施,如延迟播种期、减小种植密度等有利于提高产量或缓解减产趋势。 相似文献
15.
Climate changes, associated with accumulation of greenhouse gases, are expected to have a profound influence on agricultural
sustainability in Israel, a semi-arid area characterized by a cold wet winter and a dry warm summer. Accordingly this study
explored economic aspects of agricultural production under projected climate-change scenarios by the “production function”
approach, as applied to two representative crops: wheat, as the major crop grown in Israel’s dry southern region, and cotton,
representing the more humid climate in the north. Adjusting outputs of the global climate model HadCM3 to the specific research
locations, we generated projections for 2070–2100 temperatures and precipitations for two climate change scenarios. Results
for wheat vary among climate scenarios; net revenues become negative under the severe scenario (change from −145 to −273%),
but may increase under the moderate one (−43 to +35%), depending on nitrogen applied to the crop. Distribution of rain events
was found to play a major role in determining yields. By contrast, under both scenarios cotton experiences a considerable
decrease in yield with significant economic losses (−240 and −173% in A2 and B2 scenarios, respectively). Additional irrigation
and nitrogen may reduce farming losses, unlike changes in seeding dates. 相似文献
16.
17.
Precipitation extremes in a karst region: a case study in the Guizhou province, southwest China 总被引：3，自引：2，他引：1
Qiang Zhang Chong-Yu Xu Zengxin Zhang Xi Chen Zhaoqing Han 《Theoretical and Applied Climatology》2010,99(1-2):53-65
The topography of hilly landscapes modifies crop environment changing the fluxes of water and energy, increasing risk in these vulnerable agriculture systems, which could become more accentuated under climate change (drought, increased variability of rainfall). In order to quantify how wheat production in hilly terrain will be affected by future climate, a newly developed and calibrated micro-meteorological model for hilly terrain was linked to a crop growth simulation model to analyse impact scenarios for different European regions. Distributions of yield and growing length of rainfed winter wheat and durum wheat were generated as probabilistic indices from baseline and low (B2) and high (A2) emission climate scenarios provided from the Hadley Centre Regional Climate Model (HadRM3). We used site-specific terrain parameters for two sample catchments in Europe, ranging from humid temperate (southeast UK) to semi-arid Mediterranean (southern Italy). Results for baseline scenario show that UK winter wheat is mainly affected by annual differences in precipitation and yield distributions do not change with terrain, whilst in the southern Mediterranean climate yield variability is significantly related to a slope × elevation index. For future climate, our simulations confirm earlier predictions of yield increase in the UK, even under the high emission scenario. In the southern Mediterranean, yield reduction is significantly related to slope × elevation index increasing crop failure in drier elevated spots but not in wet years under baseline weather. In scenarios for the future, the likelihood of crop failure rises sharply to more than 60%, and even in wet years, yields are likely to decrease in elevated spots. 相似文献
18.
本文分析了黄淮海地区小麦生育期内不同时段的温度、降水与产量的关系,分别得到了不同类型的偏回归系数曲线。在此基础上,进行了不同季节温度升高对小麦产量的影响及温度、降水同时变化综合影响的模拟试验。结果表明,各地不同季节气候变暖对小麦产量的影响不同:北部、中部地区秋季、冬季变暖将导致增产,春季减产;而南部地区则秋季、春季将减产,冬季增产(河南南部略有不同)。降水量变化对各地各季气候变暖产量效应的迭加作用不同:北部、中部地区秋、冬季降水有利于增产,春季降水对减产略起缓解作用;南方各季降水过多均对小麦不利。总的说来,大部分地区若小麦生育期内气候变暖变湿,将有利于增产,但南部地区降水过多有不容忽视的负作用。 相似文献
19.
Jaak Jaagus 《Climatic change》1997,36(1-2):65-77
The paper deals with problems of temporal and spatial variability of snow cover duration, of correlation between snow cover and winter mean air temperature patterns and of the impact of climate change on the snow cover pattern in Estonia. Snow cover fields are presented in form of IDRISI raster images. Snow cover duration measured at ca 100 stations and observation points have been interpolated into raster cells. On the base of time series of raster images, a map of mean territorial distribution of snow cover duration is calculated. Estonia is characterized by a great spatial variability of snow cover mostly caused by the influence of the Baltic Sea. General regularities of snow cover pattern are determined. A 104-year time series of spatial mean values of snow cover duration is composed and analyzed. A decreasing trend and periodical fluctuations have detected. Standardized principal component analysis is used for the time series of IDRISI raster images. It enables to study the influence of different factors on the formation of snow cover fields and territorial extent of coherent fluctuations. Correlation between snow cover duration and winter mean air temperature fields is analyzed. A spatial regression model is created for estimation of the influence of climate change on snow cover pattern in Estonia. Using incremental climate change scenarios (2 °C, 4 °C and 6 °C of warming in winter) mean decrease of snow cover duration in different regions in Estonia is calculated. According to results of model calculation, the highest decrease of snow cover duration will be take place on islands and in the coastal region of West Estonia. A permanent snow cover may not form at all. In the areas with maximum snow cover duration in North-East and South-East Estonia, that decrease should be much lower. 相似文献
20.
V. Alexandrov M. Schneider E. Koleva J.-M. Moisselin 《Theoretical and Applied Climatology》2004,79(3-4):133-149
Summary Climate data used for climate variability and change analyses, must be homogeneous, to be accurate. The data currently used in the Météo-France homogenization procedure, which does not require computation of regional reference series, was applied to precipitation and average air temperature series in Bulgaria. The Caussinus-Mestre method, with a double-step procedure, was used to detect multiple breaks and outliers in the long-term series of precipitation and average air temperature. A two factor linear model was applied for break correction. The homogenization procedure was run till all or most break risk was gone. Analysis of climate variability and change in Bulgaria during the 20th century was done on already homogenized precipitation and average air temperature series. The statistical significance of the trends obtained was evaluated by the coefficient of Spearman rank correlation. The variations of annual precipitation in Bulgaria showed an overall decrease. The country has experienced several drought episodes during the 20th century, most notably in the 1940s and 1980s. Seasonal precipitation in spring shows a positive trend at most weather stations across the country. The trend for summer and autumn precipitation is negative. A statistically significant increasing trend of winter precipitation in north Bulgaria was detected. No significant warming trend in the country was found during the last century inspite of the warming observed during the last two decades. Summer in Bulgaria tends to be warmer from the beginning of the 1980s. There is a statistically significant increasing trend of average air temperature during the winter season at the weather stations near the Danube river (north Bulgaria) during the periods 1901–2000 and 1931–2000. 相似文献