关键词： 气候变化   农业可持续发展   适应技术   应对措施  

摘要： 气候变化对全球农业发展带来挑战。在气候变暖的趋势下,极端天气不断出现。气候变化增加了我国农业环境的敏感性和脆弱性。局部干旱高温加重,农作物胁迫现象严重、农业气象灾害频发、农业生态环境恶化,粮食安全问题明显,对农业可持续发展造成严重影响。本文提出从适应气候变化的视角选择合理农业技术,从缓和气候变化影响上提出应对建议措施。

关键词： 气候变化   生长度日   低温度日   高温度日   双季稻   时空特征  

摘要： 基于江西省地面气象资料和农业气象试验站数据,分析了江西省双季稻生育期的变化趋势,并利用生长度日(GDD)、低温度日(CDD)和高温度日(HDD)对1981—2007年江西省水稻各生育期热量资源的变化趋势进行分析.结果表明:气候变暖背景下,江西省水稻生长季平均气温、平均最低气温和平均最高气温均呈升高趋势,引起双季稻生长季缩短,其中,营养生长期日数减少最明显,而生殖生长期延长;生长度日和高温度日均增加,低温度日减少.研究期间,江西省双季稻有效热量资源增加,低温风险减少,但高温风险增多;江西省水稻有效热量资源的空间变化特征表现为东北部的增幅大于西南部,南部的低温风险大于北部,中部的高温风险最大.

关键词： 气候变化   农业生产   影响   措施  

摘要： 通过分析近50年来巴彦的气温、降水、积温资料,得出气温呈明显的增温趋势、积温增加、降水略有下降,气候向干暖方向发展,并着重分析了这些变化对巴彦作物种植结构、作物生长发育及农业生态环境的有利和不利影响,提出了为适应这种变化,达到农业增产增收的应对措施。

关键词： 气候变化   农业气候资源   开发应用   研究  

摘要： 应用开封市近60年的气象、作物生育期、粮食产量和农业气象试验数据,采用数理统计分析研究全球气候变暖背景下的区域气候、农业气候资源、粮食产量、作物生育期变化及其相互关系,结果表明:区域气候以冬半年为主整体变暖,近二十多年变暖加速;农业气候资源量增加,农业气候产量提高;作物生长发育加快,春季开始生长发育时间提前,秋冬季停止生长时间延后,全年作物有效生长时间延长;粮食产量在气候变暖和农业科技进步、生产方式改进等因素的共同作用下不断增长.结合田间农业气象试验和生产实践调查,提出了农业生产主动适应气候变暖,趋利避害,开发利用气候资源五项措施:调整农业结构,提高复种指数;延长作物生长发育和农业生产时间;扩大种植面积;提高农业科技水平;改善农业生产条件.最后通过讨论,提出了农业生产主动适应气候变暖,趋利避害,利大于弊的观点.

摘要： The present paper provides a geographically scaled analysis of adaptation to climate change using adoption of agricultural systems observed across Africa. Using c. 9000 farm surveys, spatial logit models were applied to explain observed agricultural system choices by climate variables after accounting for soils, geography and other household characteristics. The results reveal that strong neighbourhood effects exist and a spatial re-sampling and bootstrapping approach can remove them. The crops-only system is adopted most frequently in the lowland humid forest, lowland sub-humid, mid-elevation sub-humid Agro-Ecological Zones (AEZs) and in the highlands in the east and in southern Africa. Integrated farming is favoured in the lowland dry savannah, moist savannah and semi-arid zones in West Africa and eastern coastal zones. A livestock-only system is favoured most in the mid/high-elevation moist savannahs located in southern Africa. Under a hot and dry Canadian Climate Centre (CCC) scenario, the crops-only system should move out from the currently favoured regions of humid zones in the lowlands towards the mid-/high elevations. It declines by more than 5% in the lowland savannahs. Integrated farming should increase across all the AEZs by as much as 5%, but less so in the deserts or in the humid forest zones in the mid-/high elevations. A livestock-only system should increase by 2-5% in the lowland semi-arid, dry savannah and moist savannah zones in the lowlands. Adaptation measures should be carefully scaled, up or down, considering geographic and ecological differentials as well as household characteristics, as proposed in the present study.

关键词： Agricultural innovation systems   climate change   food security  

摘要： Climate change and variability present new challenges for agriculture, particularly for smallholder farmers who continue to be the mainstay of food production in developing countries. Recent global food crises have exposed the structural vulnerability of globalized agri-food systems, highlighting climate change as just one of a complex set of environmental, demographic, social and economic drivers generating instability and food insecurity, the impacts of which disproportionately affect poorer groups in marginal environments. Rather than search for single causes, there is a need to understand these changes at a systemic level. Improved understanding of and engagement with the adaptive strategies and innovations of communities living in conditions of rapid change provides an appropriate starting point for those seeking to shape agricultural innovation systems responsive to food insecurity and climate change. This paper draws lessons from selected country experiences of adaptation and innovation in pursuit of food security goals. It reviews three cases of systems of innovation operating in contrasting regional, socio-economic and agro-ecological contexts, in terms of four features of innovation systems more likely to build, sustain or enhance food security in situations of rapid change: (i) recognition of the multifunctionality of agriculture and opportunities to realize multiple benefits;(ii) access to diversity as the basis for flexibility and resilience;(iii) concern for enhancing capacity of decision makers at all levels;and (iv) continuity of effort aimed at securing the well-being of those who depend on agriculture. Finally, implications for policymakers and other stakeholders in agricultural innovation systems are presented.

关键词： soil respiration   spring barley   soil tillage   pasture   DNDC  

摘要： Simulation models can be valuable to investigate potential effects of climate change on greenhouse gas emissions from terrestrial ecosystems. DNDC (the DeNitrification-DeComposition model) was tested against observed soil respiration data from adjacent pasture and arable fields in the Irish midlands. The arable field was converted from grassland approximately 50 years ago and managed since 2003 under two different tillage systems;conventional and reduced tillage. Both fields were located on the same soil type, classified as a free draining sandy loam soil derived from fluvial glacial gravels with low soil moisture holding capacity. Soil respiration measurements were made from January 2003 to August 2005. Three climate scenarios were investigated, a baseline of measured climatic data from a weather station at the field site, and high and low temperature sensitivity scenarios predicted by the Community Climate Change Consortium for Ireland (C4I) based on the Hadley Centre Global Climate Model (HadCM(3)) and the Intergovernment Panel on Climate Change (IPCC) A1B emission scenario. The aims of this study were to use measured soil respiration rates to validate the DNDC model for estimating CO2 efflux from these key Irish soils, investigate the effects of future climate change on CO2 efflux and estimate the efflux uncertainties due to using different future climate projections. The results indicate that the DNDC model can reliably estimate soil respiration from the two fields examined. The model underestimated annual measured CO2 efflux from the pasture by only13% (model efficiency: ME = 0.6;root mean square error: RMSE = 1.9 and mean absolute error: MAE = 6.3) and that from the arable conventional and reduced tillage by 9% (ME = 0.6;RMSE = 1.6 and MAE = 2.4) and 8% (ME = 0.23;RMSE = 1.8 and MAE = 2.9), respectively. Short-term land use change had no significant effects on CO2 effluxes from soil. Using the high temperature sensitivity scenario, future C effluxes would inc

关键词： 气候变化   适应性措施   绩效评估   粮食产量   DID模型  

摘要： 本文基于对江苏省GEF项目区的调研,采用倍差法(D ifference inD ifference)对农业适应气候变化措施的绩效进行分析和评估。研究表明,GEF项目中农业适应气候变化措施的绩效集中体现在粮食产量上,适应性措施的实施显著地提高了项目区粮食单产水平,尤其是水稻的单产水平;适应性措施对水稻单产的净效应为42.41公斤/亩,对小麦单产的净效应为5.96公斤/亩。GEF项目的适应性措施体系可以为全国未来适应气候变化农业综合开发项目提供参考。

关键词： 全球气候变化背景   青藏高原   农业气候资源   气候倾向率  

摘要： 基于青藏高原干旱半干旱区1961—2007年55个气象站点地面观测资料,利用五日滑动平均法及GIS软件的IDW模块进行栅格处理,对比分析了研究区1961—1980年(时段Ⅰ)和1981—2007年(时段Ⅱ)各气候要素的时空变化特征及其气候倾向率.结果表明:1961—2007年,研究区喜凉作物生长季内日照时数的变化不明显,喜温作物生长季内日照时数呈增加趋势,但空间分布的变化较小;与时段Ⅰ相比,时段Ⅱ喜温作物生长季内积温值≥1500℃.d的地区面积扩大33.9%;降水量的空间分布总体表现为由东南低地向西北内陆逐渐递减,研究期间青藏高原东南部喜凉作物生长季内降水量均达到800 mm,其他地区喜凉作物生长季内降水量的气候倾向率有正有负,变幅相对较小,与时段Ⅰ相比,时段Ⅱ喜温作物生长季内降水量≥400 mm的分布面积扩大了40%;参考作物蒸散量(ET0)总体略有增加,其空间分布格局与日照时数和积温的分布相似,时段Ⅱ较时段Ⅰ喜温作物生长季内ET0≥400 mm的分布面积扩大了35.7%.研究期间,青藏高原作物生长季内的热量与降水资源有一定幅度增加,这对农牧业生产非常有利,但ET0的增大表明潜在蒸发增大,需进一步加强研究气候变化对该区域农牧业生产带来的可能影响.

关键词： 气候变化   农业   影响   对策  

摘要： 文章从近年来中国气候变化的事实和未来发展趋势入手进行分析,详细阐述了气候变化对农业生产的影响,包括对农业生产条件的影响和对农作物的影响,最后针对上述影响提出了农业开发应采取的措施。