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1.
为探明气候变化对商丘地区冬小麦产量的影响,根据1991~2010商丘市气候资料和小麦产量资料,利用数学统计与Thornthwaite Memoriae模型,结合未来气候预测结果定量分析了气候变化对冬小麦产量的影响。结果表明,冬小麦产量整体上呈波动上升趋势;主成分分析表明,气温、降水量、蒸发量与极端温度为影响冬小麦产量的主要气候因子,蒸发量过大及极端低温对冬小麦生产不利。商丘地区"暖湿型"气候有利于冬小麦生产力的提高,"冷干型"气候对冬小麦生产最为不利;未来几十年内气候可能将向"暖湿型"变化,对商丘地区粮食作物产量的提升较为有利。  相似文献   

2.
Most scenarios of greenhouse-gas climatic change predict a warmer drier Great Plains environment. The goal of this research was to determine the resulting change in soil moisture and to relate this to changes in agricultural productivity. Soil moisture was used in regression-based models to predict yields for the four major grain crops: wheat, corn, soybeans, and grain sorghum. The results indicate that a warmer drier climate would reduce yields for the summer crops throughout the state. The yield for winter wheat also decreased in the western part of the state but actually increased in eastern Kansas. Corn and soybeans could decline in the dry land crop mix in eastern Kansas as wheat becomes a more viable alternative. Thus, the results imply possible geographic shifts in the crop belts in Kansas. [Key words: climatic change, agricultural production, soil moisture.]  相似文献   

3.
In this contribution a linear first‐order differential equation is used to model glacier length fluctuations. This equation has two parameters describing the physical characteristics of a glacier: the climate sensitivity, expressing how the equilibrium glacier length depends on the climatic state, and the response time, indicating how fast a glacier approaches a new equilibrium state after a stepwise change in the climatic forcing. A prerequisite for the application of a linear model to a particular glacier is that length fluctuations over the period of interest are significantly smaller than the average length. The linear model is used to define and illustrate some concepts relevant to the study of glacier fluctuations. It is shown that glaciers are never in equilibrium with climate, and that a constant time lag between forcing and response cannot be expected. Next the linear glacier model is applied to real glaciers, showing how information on response times and a reconstruction of the climatic forcing can be extracted from length records. In the first application, two adjacent glaciers in the Oetztal Alps (Austria) are considered: Hintereisferner and Kesselwandferner. By optimizing the response times with a control method, reconstructed equilibrium‐line histories for these glaciers are almost identical. The corresponding response times are 31 years for Hintereisferner, and only 2.1 years for Kesselwandferner. In the second application, four glacier length records from the Oberengadin (Switzerland) are used to reconstruct equilibrium‐line histories. These appear to be mutually consistent, and the mean rise of the equilibrium line over the period 1894–2007 appears to be 1.4 m yr?1. An equilibrium‐line history derived from data of a nearby climate station yields about the same trend over this period, but shows significant differences on the decadal time scale.  相似文献   

4.
Over the past few decades, demand for wheat in tropical and less developed countries has outweighed local production capacity. Increasing wheat production requires prior investigation of the crop's requirements. In places with relatively low technology a naturally favourable environment is paramount for optimum production. In a tropical country such as Nigeria, climate appears to be the most critical factor for wheat growth. A new technique (or model) of delineating the savanna region of Nigeria based on its agroclimatic potential for wheat production is proposed in this study. Analytical techniques of multiple regression, hierarchical clustering and suitability rating were employed in determining the crop production potentials. Five suitability zones were identified. The study shows that the Jos Plateau and the adjacent high plains of Kaduna and Zaria have the best climate for wheat production in Nigeria. It also observes that the climatic potential for wheat production generally decreases equatorwards due to the consistently high temperatures and humidity.  相似文献   

5.
基于MODIS-NDVI的河南省冬小麦产量遥感估测   总被引:12,自引:0,他引:12  
赵文亮  贺振  贺俊平  朱连奇 《地理研究》2012,31(12):2310-2320
粮食产量估测对于国家粮食生产宏观调控具有重要意义。以河南省为例, 利用区域 NDVI数据进行冬小麦产量监测研究。基于2000~2010年冬小麦生长关键期3~5月的MODIS~ NDVI数据集, 结合河南省18地市冬小麦生产数据, 分析了研究区小麦产量和播种面 积的时间动态变化特征, 建立了基于区域NDVI的冬小麦产量估算模型。结果表明:自2000 至2010年, 研究区冬小麦产量呈上升趋势, 播种面积基本保持稳定;利用单月NDVI建立的 冬小麦产量线性模型, 平均相对误差分别为12.02%、10.70%和9.27%;利用不同月份组合 的NDVI累积和建立的冬小麦产量模型, 平均相对误差分别为11.13%、10.38%、8.37%和 9.41%;利用多个月份组合的NDVI建立的多元线性回归模型, 平均相对误差分别为 11.00%、9.32%、9.04%和9.58%;将小麦播种面积作为限制因素引入多元线性模型后, 估 算精度得到了很大提升, 平均相对误差分别为5.65%、5.34%、6.76%和5.47%.通过误差 对比后发现, 在模型中引入播种面积后, 利用区域NDVI可以有效、快速、准确地对冬小麦 进行估产。  相似文献   

6.
沿海淤泥质滩涂是中国重要的耕地后备资源之一,滩涂围垦新增的大量耕地资源的生产潜力能反映滩涂土壤粮食安全保障能力大小。本文以江苏省如东县滩涂围垦区为例,在现有的光温水气候生产潜力模型的基础上,引进基础地力贡献率和盐分限制因子作为土壤有效性系数,构建沿海地区土地生产潜力模型,并通过水稻和小麦产量对模型结果进行初步验证。研究表明:该模型具有一定可行性。滩涂围垦区水稻产量土壤基础地力贡献率为55%~59%;小麦基础地力贡献率为50%~80%。未脱盐的1982年滩涂围垦区水稻和小麦产量受到盐分阻碍的系数分别为0.73和1.00。2007年垦区由于盐分太高不能种植水稻,小麦产量受到盐分阻碍系数为0.35。未脱盐的1982年滩涂垦区土壤基础地力修正后的水稻和小麦土地生产潜力分别为12235.84和6502.23 kg/hm2;土壤盐分修正后的土地生产潜力分别为15677.42和10329.39 kg/hm2;土壤基础地力和盐分共同修正后的土地水稻和小麦生产潜力分别为8934.97和6502.23 kg/hm2。与实地调查的水稻产量(9750 kg/hm2)和小麦生产潜力(6000 kg/hm2)相比,目前土地生产力远小于盐分限制下的土地生产潜力,与基础地力和盐分双重限制下的土地生产潜力接近,改善土壤施肥技术可以进一步提高土地生产力。  相似文献   

7.
Impacts of climatic change on agriculture and adaptation are of key concern of scientific research. However, vast uncertainties exist among global climates model output, emission scenarios, scale transformation and crop model parameterization. In order to reduce these uncertainties, we integrate output results of four IPCC emission scenarios of A1FI, A2, B1 and B2, and five global climatic patterns of HadCM3, PCM, CGCM2, CSIRO2 and ECHAM4 in this study. Based on 20 databases of future climatic change scenarios from the Climatic Research Unit (CRU) , the scenario data of the climatic daily median values are generated on research sites with the global mean temperature increase of 1 ℃(GMT+1D), 2 ℃ (GMT+2D) and 3 ℃(GMT+3D). The impact of CO2 fertilization effect on wheat biomass for GMT+1D, GMT+2D and GMT+3D in China’s wheat-producing areas is studied in the process model, CERES-Wheat and probabilistic forecasting method. The research results show the CO2 fertilization effect can compensate reduction of wheat biomass with warming temperature in a strong compensating effect. Under the CO2 fertilization effect, the rain-fed and irrigated wheat biomasses increase respectively, and the increment of biomass goes up with temperature rising. The rain-fed wheat biomass increase is greater than the irrigated wheat biomass. Without consideration of CO2 fertilization effect, both irrigated and rain-fed wheat biomasses reduce, and there is a higher probability for the irrigated wheat biomass than that of the rain-fed wheat biomass.  相似文献   

8.
LIU Yujie  YUAN Guofu 《地理学报》2010,20(6):861-875
Global climate change has significant impacts on agricultural production. Future climate change will bring important influences to the food security. The CERES-Wheat model was used to simulate the winter wheat growing process and production in Panzhuang Irrigation District (PID) during 2011–2040 under B2 climate scenario based on the Special Report on Emissions Scenarios (SRES) assumptions with the result of RCMs (Regional Climate Models) projections by PRECIS (Providing Regional Climates for Impacts Studies) system introduced to China from the Hadley Centre for Climate Prediction and Research. The CERES-Wheat model was calibrated and validated with independent field-measured growth data in 2002–2003 and 2007–2008 growing season under current climatic conditions at Yucheng Comprehensive Experimental Station (YCES), Chinese Academy of Sciences (CAS). The results show that a significant impact of climate change on crop growth and yield was noted in the PID study area. Average temperature at Yucheng Station rose by 0.86℃ for 1961–2008 in general. Under the B2 climate scenario, average temperature rose by 0.55℃ for 2011–2040 compared with the baseline period (1998–2008), which drastically shortened the growth period of winter-wheat. However, as the temperature keep increasing after 2030, the top-weight and yield of the winter wheat will turn to decrease. The simulated evapotranspiration shows an increasing trend, although it is not very significant, during 2011–2040. Water use efficiency will increase during 2011–2031, but decrease during 2031–2040. The results indicate that climate change enhances agricultural production in the short-term, whereas continuous increase in temperature limits crop production in the long-term.  相似文献   

9.
One of the aims of the recently initiated land fallow policy is to encourage winter wheat abandonment in order to recover the groundwater environment of the North China Plain (NCP); although this also threatens a national secure supply of this crop, as the NCP is the major wheat producing area in China. It is therefore necessary to consider regional wheat reallocation in order to meet the twin challenges of production and water conservation. An evaluation of spatiotemporal changes in wheat area and production across China in recent years may shed light on the regions that have the potential for reallocation; such trends are analyzed in this study using agricultural statistical data. Three over-arching principles are proposed that reallocation must be naturally suitable, economically feasible, and socially acceptable, and together with the result of the spatiotemporal analysis, two continuous areas are recommended as potentially suitable for wheat reallocation—alongside the Huai River and the cold region of northeastern China. We also present strategies to improve wheat yields as well as policies for farmers, aiming to encourage the reallocation of wheat to the regions highlighted in this study.  相似文献   

10.
赵学勇  崔建垣  张铜会 《中国沙漠》1999,19(Z1):103-106
为了揭示沙化农田小麦在不同施肥条件下凋落物的产量特征和变化规律,对科尔沁沙地农田生态系统小麦凋落物产量动态与分解量进行了测定和分析。结果表明,随着施肥量由225kg·hm-2增加到300kg·hm-2和450kg·hm-2,沙地小麦凋落物总产量也由34.39g·m-2增加到了39.97g·m-2和51.58g·m-2。处理1中凋落物产量随着小麦的生长由6月1日的13.18g·m-2减少到了8.65g·m-2。处理2和处理3的凋落物的变化趋势则是中间一次(6月15日)取样测得的产量高于第一次和第三次取样的测定结果。对照则与处理1的变化趋势相反,随着时间而增加。灰分校正对准确地估测小麦的凋落物产量及其数学模型分析有着重要的意义。  相似文献   

11.
气候变化对山东省潘庄灌区冬小麦生长的影响(英文)   总被引:2,自引:1,他引:1  
Global climate change has significant impacts on agricultural production.Future climate change will bring important influences to the food security.The CERES-Wheat model was used to simulate the winter wheat growing process and production in Panzhuang Irrigation District(PID) during 2011-2040 under B2 climate scenario based on the Special Report on Emissions Scenarios(SRES) assumptions with the result of RCMs(Regional Climate Models) projections by PRECIS(Providing Regional Climates for Impacts Studies) system introduced to China from the Hadley Centre for Climate Prediction and Research.The CERES-Wheat model was calibrated and validated with independent field-measured growth data in 2002-2003 and 2007-2008 growing season under current climatic conditions at Yucheng Comprehensive Experimental Station(YCES),Chinese Academy of Sciences(CAS).The results show that a significant impact of climate change on crop growth and yield was noted in the PID study area.Average temperature at Yucheng Station rose by 0.86℃ for 1961-2008 in general.Under the B2 climate scenario,average temperature rose by 0.55℃ for 2011-2040 compared with the baseline period(1998-2008),which drastically shortened the growth period of winter-wheat.However,as the temperature keep increasing after 2030,the top-weight and yield of the winter wheat will turn to decrease.The simulated evapotranspiration shows an increasing trend,although it is not very significant,during 2011-2040.Water use efficiency will increase during 2011-2031,but decrease during 2031-2040.The results indicate that climate change enhances agricultural production in the short-term,whereas continuous increase in temperature limits crop production in the long-term.  相似文献   

12.
A critical examination of Hubbert’s model proves that it does not account for several factors that have significantly influenced the production of petroleum and other fossil fuels. The effect of these factors comes into the price of the fossil fuels, and the latter has a significant influence on the demand and rate of production of energy resources as well as on the long-term rate of production growth at both the regional and global levels. Based on several observations of historical production data, a simple mathematical model is constructed and presented in this paper for the lifetime of a fossil fuel resource. The recent data of global petroleum and natural gas production show that a very important period in the life of energy resources is a period when the demand of these resources increases almost linearly. The linear part of the production curve makes the entire lifetime production of the resource asymmetric. Information on the total available quantity of a resource at any time and of the average slope during this linear period yields an estimate of the timescale, T 2, when peak production is reached and depletion follows. The total available quantity of the energy resource is laden with significant uncertainty, which propagates in the estimates of the timescale of the peak production in any resource model. The time asymmetry of the current model leads to a delay of the timescale, when the onset of the resource production commences (e.g., peak oil). However, the rate of the resource production decline is significantly higher than that predicted by other models that use a symmetrical curve-fitting method.  相似文献   

13.
民勤春小麦NDVI与产量的关系及其对气候变暖的响应   总被引:3,自引:0,他引:3  
应用1982—2003年的GIMMS NDVI时间序列遥感数据集和民勤站气象资料以及1985—2000年民勤作物物候期观测和产量资料,借助于GIS技术,在识别春小麦种植区的基础上,分析了其生长季平均NDVI与产量的相关关系,并采用时滞互相关法对月际尺度的平均气温、最高气温、最低气温、降水和日照时数与春小麦NDVI的相互关系进行研究,建立了春小麦生长季平均NDVI对气候因子的响应关系模型。结果显示,民勤县春小麦生长季平均NDVI与单产产量极度相关;月际尺度上,春小麦NDVI与平均气温、最高气温、最低气温和降水相互作用同步,而滞后于日照时数1个月,且气温和降水对春小麦NDVI影响时效为1个月,日照时数为2个月;近年来,日照时数延长和降水增多有利于春小麦NDVI的增加及产量的提高。  相似文献   

14.
The aim of this study was to evaluate four metrics to define the spatially variable (regionalised) hillslope sediment delivery ratio (HSDR). A catchment model that accounted for gully and streambank erosion and floodplain deposition was used to isolate the effects of hillslope gross erosion and hillslope delivery from other landscape processes. The analysis was carried out at the subcatchment (~ 40 km2) and the cell scale (400 m2) in the Avon-Richardson catchment (3300 km2), south-east Australia. The four landscape metrics selected for the study were based on sediment travel time, sediment transport capacity, flux connectivity, and residence time. Model configurations with spatially-constant or regionalised HSDR were calibrated against sediment yield measured at five gauging stations. The impact of using regionalised HSDR was evaluated in terms of improved model performance against measured sediment yields in a nested monitoring network, the complexity and data requirements of the metric, and the resulting spatial relationship between hillslope erosion and landscape factors in the catchment and along hillslope transects. The introduction of a regionalised HSDR generally improved model predictions of specific sediment yields at the subcatchment scale, increasing model efficiency from 0.48 to > 0.6 in the best cases. However, the introduction of regionalised HSDR metrics at the cell scale did not improve model performance. The flux connectivity was the most promising metric because it showed the largest improvement in predicting specific sediment yields, was easy to implement, was scale-independent and its formulation was consistent with sedimentological connectivity concepts. These properties make the flux connectivity metric preferable for applications to catchments where climatic conditions can be considered homogeneous, i.e. in small-medium sized basins (up to approximately 3000 km2 for Australian conditions, with the Avon-Richardson catchment being at the upper boundary). The residence time metric improved model assessment of sediment yields and enabled accounting for climatic variability on sediment delivery, but at the cost of greater complexity and data requirements; this metric might be more suitable for application in catchments with important climatic gradients, i.e. large basins and at the regional scale. The application of a regionalised HSDR metric did not increase data or computational requirements substantially, and is recommended to improve assessment of hillslope erosion in empirical, semi-lumped erosion modelling applications. However, more research is needed to assess the quality of spatial patterns of erosion depicted by the different landscape metrics.  相似文献   

15.
1961-2011年山东气候资源及气候生产力时空变化特征   总被引:7,自引:0,他引:7  
基于山东省21个气象站1961-2011年的气象资料,利用线性趋势、IDW空间插值、Mann-Kendall检验、Fisher最优分割等方法分析了气温和降水的时空变化特征;在此基础上采用Thornthwaite Memorial模型对植被气候生产力的时空演变进行了研究,并探讨了气候生产力对气温和降水的敏感性。结果表明:近51年来山东省普遍增温,倾向率为0.359℃/10a,中部地区升温明显;年降水量在剧烈波动中略呈下降趋势,20世纪80年代降水量的变率较大,山东北部、东部、东南部降水量减少幅度较大。近51年来气候生产力存在较明显波动,总体呈增加趋势,但递增速度不显著,1981-1989年气候生产力最低,2003-2011年达到最高水平;气候生产力由北向南,由西向东逐渐增加,山东西南部气候生产力增加较多。“暖湿型”气候对作物气候生产力有利,气候变暖有利于气候生产力的提高,但降水量少是限制气候生产力的主要因素。  相似文献   

16.
Climate change has the potential to affect terrestrial ecosystems and, thereby, the carbon cycle. Various vegetation biomes are likely to respond differently to changes in climatic factors. The purpose of this study was to analyse the trends of the terrestrial vegetation productivity and climate drivers on regional levels and relations between ones. The gross primary productivity from the global satellite-based terrestrial production efficiency model (PEM) MOD17 as the vegetation productivity indicator and meteorological data from the weather station network as climatic indicators were used. The analysis covered a period from 2000 to 2012. Correlation analysis was used to quantify the association between the vegetation productivity and climatic indicators for different growing seasons and landscape-climatic zones of Ukraine. The Mann–Kendall trend test was applied to take into account seasonal features. Multiple linear regression models for corresponding seasons and zones have been simulated using the principal component analysis. The results showed no detectable limiting effect of the climatic drivers on plant productivity for forest areas. The limiting effect of the temperature increasing and precipitation amount decreasing for the steppe zone and eastern forest-steppe subzone of Ukraine for summer was observed.  相似文献   

17.
气候变化对甘肃定西、安徽合肥小麦生产影响研究   总被引:5,自引:0,他引:5  
由于大气中温室气体的不断增加, 全球气候发生了巨大变化。据最新气候模式模拟研究表 明未来全球气候将发生更为剧烈的变化, 这必将对很多部门产生显著的影响特别是对气候变化 十分敏感的农业。尤其对于中国这样的人口大国, 农业作为社会最基本也是最重要生产部门之 一, 气候变化将对中国的农业生产带来巨大的影响。小麦是中国的第二大作物, 其中冬小麦占全 国小麦总产量近90%, 因此评价气候变化对中国小麦生产影响是十分必要的。为了分析在未来气 候变化情景下中国小麦生产可能遇到的风险, 以15 年ECMWF 再分析实验数据(1979~1993)作为 边界条件驱动PRECIS 区域气候模式模拟产生作物模型所需要的气候资料并输入CERES-Wheat 模型, 验证CERES-Wheat 模型与区域气候模式PRECIS 结合的模拟能力。在以上验证工作的基 础上, 将区域气候模式PRECIS 的模拟结果与作物模型CERES-Wheat 相连接, 同时考虑到CO2 对小麦的直接施肥作用, 模拟了两个小麦站点(定西和合肥)在IPCC SRES A2 和B2 情景下雨养 和灌溉小麦的变化趋势。得到如下结论: 无论是在A2 情景还是B2 情景, 定西和合肥的小麦产量 都会有所增加, 但增加的幅度相差很大。A2 情景的增产效应一般要大于B2 情景的增产效应, 灌 溉小麦比雨养小麦更加受益于气候变化, 冬小麦(合肥) 产量的增长幅度要大于春小麦(定西) 增 长幅度。CO2 对小麦生长的肥效作用十分明显, 产量增幅很大。以上结果说明未来气候变化可能 会对我国的小麦生产带来益处, 但由于未来气候情景模拟的不确定性以及CO2 肥效作用通常是 在作物过程中的水肥条件完全满足的情况下才充分体现, 这都给研究结果带来了不确定性, 但本 项研究为评价未来气候变化对中国小麦生产影响提供了一种全面的评价方法。  相似文献   

18.
气候变暖背景下中原腹地冬小麦气候适宜度变化   总被引:6,自引:0,他引:6  
朱新玉  刘杰  史本林  张怡 《地理研究》2012,31(8):1479-1489
通过构建冬小麦光照、温度、降水及综合气候适宜度计算模型,探讨气候变化对冬小麦气候适宜性的影响。结果表明:冬小麦全生育期温度、光照、降水及综合气候适宜度均值分别为0.54、0.64、0.37及0.50;冬小麦对光照适宜性较好,降水是限制冬小麦生长发育的主要因子;温度和降水适宜度以0.001·a-1线性趋势下降,光照适宜度以0.002·a-1线性趋势下降,气候因子匹配效果变差对冬小麦的生长不利。冬前生长阶段温度、光照和降水适宜性较弱,各气候因子匹配效果较差。出苗-拔节期降水适宜性较强,各气候因子组合效果较差;拔节-抽穗期和抽穗-乳熟期温度与光照适宜性较强,水分胁迫较大,气候因子组合效果趋好。乳熟-成熟期光照和降水适宜性较强,综合气候适宜性变差。光照、温度和降水适宜度在全生育期的中后期与冬小麦产量的相关性比较显著。  相似文献   

19.
This article contributes to research on how climate change will impact crops in China by moving from ex-post empirical analysis to forecasting. We construct a multiple regression model, using agricultural observations and meteorological simulations by GCMs, to simulate the possible planting boundaries and suitable planting regions of spring wheat under RCP4.5 scenario for the base period 2040s and 2070s. We find that the south boundary of possible planting region for spring wheat spreads along the belt: south Shandong-north Jiangsu-north Anhui-central Henan-north Hubei-southeast Sichuan-north Yunnan provinces, and will likely move northward under RCP4.5 scenario in 2040s and 2070s, resulting in the decrease of possible planting area in China. Moreover, the sowing and harvest date of spring wheat in the base period shows a gradually delayed phenomenon from the belt: south Xinjiang - Gansu, to the Tibet Plateau. As a result, the growth period of spring wheat in China will shorten because of the impacts of climate change. These results imply that a variety of adaptations measures should be set up in response to changing climatic conditions, including developing the planting base for spring wheat, restricting the planting area of spring wheat in sub-suitable areas at risk while expanding the planting area of optimal crops.  相似文献   

20.
鲁西北地区土地现实生产力调查与估算   总被引:3,自引:0,他引:3  
以鲁西北地区县级1∶5万土壤类型图图斑作为基础评价单元,根据农户现有的投入水平,采用“调查法”模拟分析农业土地资源的现实生产力,并与统计资料和“机制法”模型模拟结果进行对比分析。研究结果表明,现实投入水平下鲁西北地区夏玉米单产略高于冬小麦单产,对冬小麦的投入从整体上来看相当于中等投入,但又存在着区域差异。对夏玉米的投入具有南北向的差异,由南到北投入水平逐渐降低。鲁西北地区土地现实生产力以宁津县最高,庆云县最低,与“机制法”模型模拟结果比较,各县市之间土地生产潜力差距较大。由此可以说明,各县市土壤质量本身对土地年生产力的大小起着重要作用,进一步证明“调查法”能充分反映土壤在土地综合性质中的主要作用。  相似文献   

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