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平凉地区气候变化对粮食作物产量的影响 总被引：1，自引：0，他引：1
引 言2 0世纪 80年代以来 ,全球气候发生了较为显著的变化 ,气候变化给农业生产带来了各种影响 ,文中以本区主栽的冬小麦、玉米为例 ,探讨了近几十年来气候变化对作物产量所产生的影响。1 作物气象产量逐年变化分析粮食产量 ( ｙ)一般由时间趋势产量 ( ｙｔ)、气候产量 ( ｙｗ)和随机误差 ( ｙε) 3项构成 ,一般随机误差( ｙε)可忽略不计 ,因此作物实际产量用下式表示 :ｙ =ｙｔ+ ｙｗ以平凉市的冬小麦和玉米为例 ,应用正交多项式分别将冬小麦和玉米的实际产量分解为时间趋势产量和气候产量 ,分别作出两种作物气候产量随时间变化图 (图 1… 相似文献
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气候变化对作物产量影响的动态统计评价模式，是将积分回归原理引进到气候影响评价服务中来，建立了以旬为时间单位的气温、降水、日照的旬值变化对作物产量形成的最佳定量影响关系，可使气候影响评价工作直接为农业生产进行及时连续的跟踪服务。气候动态影响规律实质是正常气候条件与作物生长的供需规律，因此该模式还有多种用途可供开发利用。 相似文献
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IPCC第五次评估报告（AR5）第二工作组（WGII）报告认为,气候变化对世界上大部分区域的自然和人类系统的影响将进一步加剧,其对非洲最大的影响预计发生在半干旱的环境,增加现有的水资源可利用量和农业系统的压力;气候变化已导致北欧地区的谷物产量增加而南欧地区的产量降低,未来的变化将增加欧洲的灌溉需求;在亚洲的许多地区,气候变化将导致农业生产率下降;气候、大气CO2和海洋酸化的进一步变化预计将对大洋洲的水资源、海岸生态系统、基础设施、健康、农业和生物多样性产生实质性的影响;在北美,许多带来风险的气候压迫力的频率和强度将在未来几十年增加;中美洲和南美洲许多国家的持续高水平贫困导致了对气候变率和变化的高脆弱性;在北极,气候变化与非气候相关驱动在确定的物理、生物和社会经济风险上交互作用,变化率可能超过了社会系统适应的速率;在气候和非气候因素的影响下,小岛屿具有高度的脆弱性,同时,气候变暖将增加海洋生态系统的风险。 相似文献
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近30年我国气候变化的不稳定性及其与农业生产的关系 总被引：6，自引：0，他引：6
引入信息论中熵值分析方法，利用全国七大区１９６１－１９９０年的气象和产量资料，讨论了近年平均气温，最高气温，最低气温和降水量的熵值时空变化类型。详细分析了我国气候变化的不稳定性，在此基础上，定性讨论了气候波动与农业气象灾害的关系及其对农业产量的影响，并分区建立了产量与气象要素熵的回归模型。 相似文献
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陇中黄土高原气候生产潜力时空变化及水热因子驱动分析 总被引：1，自引：0，他引：1
《干旱气象》2015,(5)
根据陇中黄土高原27个气象台站1971~2013年气象资料,采用Thornthwaite Memorial模型计算气候生产潜力,通过经验正交函数(EOF)方法分析其变化特征。研究表明:研究区域升温明显,降水以及气候生产潜力呈波动性变化,实际产量占气候生产潜力的43.8%(2000~2013年),农业开发力度还待大幅提升。气候生产潜力南高北低,纬向分布差异明显;在热量驱动下温度每降低1℃,气候生产潜力减产22 kg·hm-2·a-1;温度每增加1℃,气候生产潜力增产18 kg·hm-2·a-1,热量不足对农业产量有明显抑制作用;在水分驱动下每减少10 mm降水,气候生产潜力将减产11 kg·hm-2·a-1;降水每增加10 mm时,气候生产潜力将增加10 kg·hm-2·a-1。在热量、水分双驱动时气候生产潜力同步叠加了水热条件的共同影响,加大水热供应量将会有效提升农业产量,并且使气候生产潜力差异性变化趋缓。驱动效益分析将陇中黄土高原划分为4个区域,在不同区域农业发展需要因地制宜,区别对待。 相似文献
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随着农作物产量的逐步提高,气候因素在农业生产上的影响越显突出。土壤水份的变化不但直接影响着农作物的生长,而且与气候因素之间有着密切联系。这里就柳州沙塘地区旱地浅层土壤水份变化的若干特征与气候因素的联系方面,试作一些初 相似文献
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小麦是甘肃省主要粮食作物之一,近年来播种面积已接近粮食作物的59％。但是产量受气候影响大,各地单产高低差异显著,产量波动形成明显的时空分布。众所周知,农业收成年景好坏与气候条件联系密切,而且一般研究认为,农业产量形成中气候影响 相似文献
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In recent years,a large number of papers on the climatic sudden change have been presented.From the viewpoint ofclimatic sudden change,two methods of studying climatic sudden change are applied in this paper.The Northern Hemi-sphere land temperature(NHLT)during 1851—1984,China temperature(CT)during 1873—1990 and the NorthernHemisphere sea-level pressure(NHSLP)at each grid point during 1899—1987 are analyzed by the moving T-test.Theresults show that there exist two climatic sudden changes in the 1920s and the 1950s during the past 100 years,and thenfeatures of circulation for the two sudden changes are discussed by the NHSLP data. 相似文献
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T. C. Whitmore 《Climatic change》1998,39(2-3):429-438
Tropical rain forests are dynamic and continually regenerating by growth of seedlings up from the forest floor into canopy gaps that form on a cycle of usually a century of more in length. Changes in seedling establishment, survival, and release in gaps could thus change canopy species composition for a long time. Of likely climatic changes, evidence is presented that cyclone occurrence and increased rainfall seasonality could have important effects on seedling ecology. These forests and their species have lived through big Pleistocene and Holocene climatic changes, but today they are fragmented by human impact and so have less resilience to future climatic change. Management to accommodate climatic change should aim to reduce fragmentation and also canopy opening during logging operations. These are the same practices as advocated for biodiversity conservation. Tropical seasonal forests are also likely to be altered by expected climatic change, and also mainly at their regeneration stage. 相似文献
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Benjamin Santer 《Climatic change》1985,7(1):71-93
An investigation is made of the possible impacts of a climatic change (induced by a doubling of atmospheric carbon dioxide concentration) on the European agricultural sector. Two general circulation models have been used to develop climatic change scenarios for the European study area. From the scenarios, information was obtained concerning the possible behavior of temperature, precipitation, solar radiation, and relative humidity in the altered climatic state. This meteorological information was then employed in two separate crop-weather models - an empirical/statistical model (for winter wheat) and a simple simulation model (for biomass potential). This type of approach represents a considerable departure from that employed by previous large-scale climate impact studies. Both the seasonal and regional components of a possible climatic change are incorporated directly in the two crop-weather models. The results of this investigation demonstrate that a simple crop-weather simulation model may be more suitable for the purposes of agricultural impact analysis than the linear regression models frequently used in such studies. In order for such an impact analysis to be accepted as a valid scientific experiment, a full presentation of the underlying assumptions and uncertainties is essential. 相似文献
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选取参与东北地区短期气候预测业务质量评估的53个气象站的月平均气温、降水资料,NCEP/NCAR再分析的月平均500 hPa位势高度场资料,以及由NOAA重构的海温场资料,对比了新、旧气候平均态下,冬、夏季东北地区气温、降水及全球500 hPa位势高度场及海温场差异, 并分析了气候平均值改变对气候变化、影响评价和预测业务的影响。结果表明：就东北大部分地区而言,新气候态（1981-2010年）表征的气候较旧气候态（1971-2000年）更暖湿;新气候态的全球500 hPa位势高度值和海温值较旧气候态均有所增大;新气候态下东亚大槽强度和西伯利亚高压强度变弱是造成东北冬季气温升高的主要原因;西太副高和鄂霍次克海阻塞高压强度增强,是造成东北地区大部分月份降水量增加的主要原因;而东北冷涡强度减弱是造成东北地区6月降水量减少的主要原因;9月和10月降水量减少可能与海温的变化有关。气候平均值的改变会对气候业务产生影响,如需对冷冬事件和ENSO事件重新评估,对极端事件重新分析,及对要素预报量级和趋势产生影响。 相似文献
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本文分析了近500年黄河流域旱涝的演变特征，并且利用几个较著名的全球三维环流模式的模拟结果分析了各种物理因子对华北地区旱涝影响的大小，同时利用观测资料亦分析了这些物理因子与黄河流域旱涝的相关。 相似文献
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There is unequivocal evidence of increased air temperatures in Spain as a result of climate change. Using organic matter, nitrate and soluble reactive phosphorus concentrations, we reconstructed changes in water quality in 15 montane, pristine streams between 1973 and 2005 in Spain. We also measured how loading rates of these variables change as a function of shifting temperatures. Almost half of tested variables were related with hypothesized trends of climatic change for air temperature. Concerning extreme events, the hypothesis of climatic change matched in 33% of all relationships, which mostly occurred in Northern Spain. Regional gradients of population change and soil degradation, however, did not explain the geographical distribution of climatic change effects. The main reason that effects on water quality are not ubiquitous and that constraining factors are hardly detected may be that long-term signals are the outcome of several interacting processes. These are still poorly known and may act at different spatial and temporal scales. Hence, a case-by-case approach might prove more fruitful than a regional one when studying water quality responses to climatic change. Consideration of the balance between extreme and normal events (storm- vs baseflow), catchment effects (land use and its effects on evapotranspiration and runoff) and in-stream processes (outgassing, mineralization, burial) could help increase our understanding of the responses of water quality to climatic change. 相似文献
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Christopher R. Bryant Barry Smit Michael Brklacich Thomas R. Johnston John Smithers Quentin Chjotti Bhawan Singh 《Climatic change》2000,45(1):181-201
The effects of climatic variability and change on Canadian agriculture have become an important research field since the early 1980s. In this paper, we seek to synthesize this research, focusing on agricultural adaptation, a purposeful proactive or reactive response to changes associated with climate, and influenced by many factors. A distinctive feature of methods used in research on adaptation in Canadian agriculture is the focus on the important role of human agency. Many individual farmers perceive they are well adapted to climate, because of their extensive 'technological' tool-kit, giving them confidence in dealing with climatic change. In many regions, little concern is expressed over climatic change, except where there are particular types of climatic vulnerability. Farmers respond to biophysical factors, including climate, as they interact with a complex of human factors. Several of these, notably institutional and political ones, have tended to diminish the farm-level risks stemming from climatic variability and change, but may well increase the long term vulnerability of Canadian agriculture. Notwithstanding the technological and management adaptation measures available to producers, Canadian agriculture remains vulnerable to climatic variability and to climate change. 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