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1.前言过去的十多年里,在环境一作物模式的研究方面,不同学科的科学家们均给予了足够的重视。这种状况是由世界粮食危机的局面造成的。其触发条件有两个:一是由于世界人口的迅速增长导致人类对粮食需要量的增 相似文献
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沙奕卓 《中国气象科学研究院年报》2001,(1)
项目背景:中国是世界上的农业大国,也是人口大国,每年都有大量农产品进出口。我国有关单位为了做好每年的粮食进出口工作,迫切需要预先掌握世界各国(主要供需国)的农产品产量情况,以便选择合理的粮食进出口时机,提前安排储运、远洋运输、资金调配等。 相似文献
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NCAR的Dai等人关于全球河流流量的研究表明,全球人口密集地区的一些河流水位正在下降,其原因与气候变化有关。这种变化可能对全球粮食和水供应造成潜在威胁。该研究结果刊登在美国气象学会2009年5月15日的Journal of Climate杂志上。 相似文献
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1引言干旱是一种严重的自然灾害,是一种因无降水或降水异常偏少造成空气干燥、土壤缺水的气候现象。它的直接危害是造成农牧业减产,人畜饮水发生困难,生态平衡受到破坏。我国是一个人口大国,粮食问题始终是关系国家安全、社会稳定的重大战略问题,与其它自然灾害相比,旱灾是影响我国粮食生产的主要因素,因为旱灾造成的粮食损失要占全部自然灾害粮食损失的一半以上。黑龙江省是全国产粮大省,粮食基地,干旱监测和影响评估服务一直是农业气象服务和决策气象服务的主要内容。目前常见的干旱指数有降水量(P)和降水量距平百分率、标准化降水指数(SPI或Z)、相对湿润指数、综合干旱指数、土壤墒情干旱指数、Palmer干旱指数等。 相似文献
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粮食作物产量的形成与光温水等气象条件关系密切。我们通过对全省粮食作物产量的时空分布、产量与气象条件相关关系的统计计算,初步分析了我省粮食作物产量划区、增减产年型和影响我省粮食作物产量形成的主要相关时段与气象因子。 相似文献
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国外农业气象概况和水平 总被引:1,自引:0,他引:1
随着整个科学技术的迅速发展,农业气象学也有了很大发展。世界各国和有关国际组织也愈来愈重视农业气象工作了。前世界气象组织主席塔哈在《世界气象组织未来》一文中指出,“为了满足世界人口迅速增加所需要的粮食增产的要求,该组织应在农业气象方面做出极大的努力……”。1975年召开的第七届世界气象大会,也将“农业气象支援粮食生产计划”列为大会的新计划。会议要求世界各国加强农业气象组 相似文献
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粮食生产是个综合性的系统工程,制约的因素很多,有政策问题,也有土壤条件、农业技术措施、种子、肥料、农药、水利等,还有受自然气候的直接影响。气象因子对粮食生产的影响,笔者曾在1977年作了研究。本文就厄尼诺与金华市粮食生产的关系作一初步分析。 相似文献
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哲里木地区近40年气温、降水变化特征分析 总被引:1,自引:0,他引:1
哲里木地区近40年气温、降水变化特征分析申广立(哲盟气象处)引言气候变化对社会进步和经济发展有重要影响。当今,干旱、洪涝和低温冷害等灾害破坏着人类赖以生存的粮食、水和能源等条件,全球约有35%的土地和20%的人口受到持续干旱和沙漠化的威胁,气候异常给... 相似文献
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三江地区位于我国东北端,包括三江平原、兴凯湖平原及其毗邻地带,面积约10万余平方公里,是我国重要的商品粮基地和垦区之一。本文分析计算了三江地区的光、热资源,着重探讨了光温潜力。考虑温度对不同作物生产力的影响,我们提出一种计算C_4作物、C_2喜凉作物和C_3喜温作物的温度影响参数的经验公式。据此,估算了三江地区春小麦、大豆、玉米和水稻等四种主要农作物的生产潜力;并与实际高产值作了比较。最后,就三江地区光、热资源的开发利用问题进行了讨论。 相似文献
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山东省主要粮食作物气候生产潜力时空变化特征 总被引:2,自引:0,他引:2
根据山东省1961-2008年的气象资料,利用逐级订正法计算了山东省冬小麦和夏玉米等主要粮食作物的气候生产潜力,并进一步采用经验正交函数分解方法,探讨了其时空变化特征.结果表明:山东省冬小麦及夏玉米的气候生产潜力存在有明显的年际波动和空间差异,其中冬小麦优、劣年景气候生产潜力相差3~9倍,夏玉米相对较小,为2~3倍;全省冬小麦、夏玉米气候生产潜力的高值区位于水热条件匹配较好的鲁南地区,低值区在半岛东部沿海地区;冬小麦、夏玉米气候生产潜力与实际单产的年际变化基本一致,山东省粮食产量,特别是夏玉米产量的年际波动受作物生长期间气候条件影响较大;全省冬小麦、夏玉米气候生产潜力在空间上具有较好的一致性,区域互补性较差. 相似文献
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海南岛农业气候生产力的估算 总被引:1,自引:0,他引:1
发挥气候资源的生产潜力,是农作物增产的有效途径。本文用Lieth法估算海南岛的农业气候生产力。光、热、水资源丰富的海南岛,植物的气候产量高,农作物的增产潜力至少为现在生产水平的一倍以上。水分是海南岛(尤其是西南部)农业产量的主要限制性因子。通过灌溉来补充所欠缺的水分(全岛平均每公顷需灌溉1778吨水),可期望达到最大气候产量。 相似文献
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In this article the theoretical method to determine the optimum seeding time of wheat and maize isestablished.For wheat,it is based on the close relationship between accumulated temperature and numberof leaves on the main stalk as well as number of stalks per plant of wheat,and for maize,based on theclimatic potential productivity model of maize.Using these models,we found that the optimum seeding time should be,for winter wheat,decided byaccumulated temperature from seeding date to the beginning of dormancy,and for maize,postponed forabout 30 days for medium variety and about 50 days for early variety in contrast with traditional seedingtime.Besides,through analysing climatic data the agroclimatic pattern of optimum seeding time for bothcrops in Beijing area has been found as well. 相似文献
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Russian agriculture sensitivity to changes in climate, soil and atmosphere chemistry were analyzed. Calculated data are presented on crop productivity of grain crops and grasses (C3) under arid and humid scenarios of climate taking account of one-, two-, three and four-factor natural environment impacts. All four factors under studies (climatic parameters, CO2 and tropospheric ozone concentrations, soil degradation extent) greatly impact agriculture productivity. The effect of interaction between all considered factors on agroecosystem productivity is studied. It is established that a simple additive scheme for explaining the complex effect of some factors can be much violated. In this case, not only variations in the mean crop yield levels but also variations in the degree of crop stability have been assessed in some regions, that may be more important for determining the social-economic consequences. It turned out that the recurrence of critically very low yields in steppe regions may increase two fold as a result of global warming. 相似文献
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Sensitivity of agricultural production to climatic change 总被引:2,自引:0,他引:2
P. A. Oram 《Climatic change》1985,7(1):129-152
Although the range of cultivated species is relatively restricted, domestic plants and animals exhibit considerable resilience to stochastic shocks, and the study of their ecological adaptability and critical physiological and phenological requirements is a valuable first step in determining their possible response to climatic change. Methods of assessing agroclimatic suitability and their limitations are discussed, and suggestions are made for simulating the probable impact of shifts in the main climatic parameters on the productivity and spatial distribution of key crops and livestock. Some regions and crops are climatically more vulnerable than others: some regions (in particular North America) are strategically more critical to the stability of world food supplies, while in others resources for agricultural production are under more severe pressure.As well as attempts to forecast long-term climatic trends and their effects on agriculture, combating climatic variability merits high priority. This is an ever-present source of instability in production and could be enhanced in association with changing climate. Its magnitude differs widely among crops and geographical regions, but its impact from year to year is often greater than that predicted from climatic change even in extreme scenarios. The paper indicates a number of potentially desirable areas for action and suggests that several of these would be beneficial both as a buffer against short-term effects of variability and as a means of combating climatic change. 相似文献
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泡桐林生产潜力估算及气候影响 总被引:2,自引:0,他引:2
根据泡桐生理生态特性和分布区20个站点辐射,温度,降水等气候资料,得出泡桐在不同地理区的气候生产潜力和分布规律。分析了未来气候变化对我国泡桐生产影响的一般情形和相应对策,为更好地开发利用泡桐林生态系统提供依据。 相似文献
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Andrew Challinor Tim Wheeler Chris Garforth Peter Craufurd Amir Kassam 《Climatic change》2007,83(3):381-399
Africa is thought to be the region most vulnerable to the impacts of climate variability and change. Agriculture plays a dominant
role in supporting rural livelihoods and economic growth over most of Africa. Three aspects of the vulnerability of food crop
systems to climate change in Africa are discussed: the assessment of the sensitivity of crops to variability in climate, the
adaptive capacity of farmers, and the role of institutions in adapting to climate change. The magnitude of projected impacts
of climate change on food crops in Africa varies widely among different studies. These differences arise from the variety
of climate and crop models used, and the different techniques used to match the scale of climate model output to that needed
by crop models. Most studies show a negative impact of climate change on crop productivity in Africa. Farmers have proved
highly adaptable in the past to short- and long-term variations in climate and in their environment. Key to the ability of
farmers to adapt to climate variability and change will be access to relevant knowledge and information. It is important that
governments put in place institutional and macro-economic conditions that support and facilitate adaptation and resilience
to climate change at local, national and transnational level. 相似文献