The impact of climate change on global food supply and demand, food prices, and land use

Climate change induced crop yield change affects food production of countries to varying degrees, depending on the location of the farming activities. Differentiated yield changes of crops may lead to reallocation of agricultural land among uses. Key food exporters may reshuffle due to diverse climate change impact on crop farming among countries. We use a multi-region, multi-sector computable general equilibrium (CGE) model, which considers crop suitability of land in the optimal reallocation decision of land between uses, to simulate the impact on global food production, prices, and land use of crop yield change due to climate change as projected under the IPCC SRES scenario A2. Our findings show that developing countries are more adversely affected by climate change than developed countries. Developed countries are mostly located in higher latitudes, and climate change benefits the crop yield of these areas. In contrast, developing countries of the lower latitudes suffer from the reduction in crop yield being induced by climate change. Considering the fast growing population in the developing world, developed countries are expected to serve as the world’s key food exporters by 2020 should the climate change occurs as scenario A2 indicates.     

The Potential Effect of Climate Change and Elevated Air Carbon Dioxide on Agricultural Crop Production in Central and Southeastern Europe

SUMMARY

The vulnerability and adaptation of major agricultural crops to different soils in Austria and Bulgaria under a changing climate and elevated air CO₂ were investigated. Several incremental and transient GCM climate change scenarios were created and applied. Warming will decrease the crop-growing duration of the selected crops in the regions of interest. All GCM scenarios, including the climate change effect only, projected reductions in grain yield of winter wheat and spring barley, caused by a shorter crop-growing period. However, when the direct effect of an increased CO₂ level was assumed, most GCM climate change scenarios projected an increase in wheat and barley yield and especially in soybean yield. An increased level of CO₂ alone had no significant impact on the simulated maize yield reductions under climate change.     

Assessment of agricultural drought vulnerability to climate change at a municipal level in South Korea

This study aimed to analyze the future vulnerability to agricultural drought of the Korean administrative units of cities (Si) and counties (Gun) following the climate change phenomenon. To assess the vulnerability in a quantitative manner and also to deal with different physical and socioeconomic data on the occurrence of agricultural drought, principal component analysis (PCA), a multivariate statistical analysis method, was adopted, and a vulnerability index, regional vulnerability index to agricultural drought (RVI_AD), was suggested. RVI_AD having a range from 0.0 to 1.0 was calculated by rescaling the weighted summation of principal component scores. The analysis was performed with all 21 standardized variables in each administrative unit of Si and Gun: 3 sensitivity variables, 8 exposure variables, and 10 adaptation variables. It resulted in four principal components explaining about 85.7% of the total variance, and the third principal component, comprised of only climate variables, was used for applying future climate data from the RCP 8.5 scenario. The districts of Chungchongnam-Do (M1), Jeollabuk-Do (L1), and Jeollanam-Do (L2) were evaluated as having the highest vulnerability to agricultural drought based on the climate change scenario, not only in the present but also in future. Despite the limitation inherent in the PCA, the approach in this study could reflect different factors other than climate factors on minimizing subjective interruption, and such is expected to contribute to improving the decision-making for diagnosing the drought adaptation capacity in a region and developing measures to mitigate the drought damage.     

Weather-induced economic damage to upland crops and the impact on farmer household income in Northeast Thailand

Paddy and Water Environment - In Thailand, climate change has a direct effect on the export of food and agricultural products, which is one of the main revenue sources of the country. Furthermore,...     

Impact of climate change on paddy field irrigation in southern Taiwan

Climate change can have a serious impact on water resources. The main agricultural product in southern Taiwan is rice, the planting of which consumes far more water than other crops. This makes agriculture in Taiwan especially vulnerable to climate change. In this study, we used the generalized watershed loading functions (GWLF) hydrological model to simulate the discharge of the Kaoping River under climate change scenarios A2 and B2 as released by the Intergovernmental Panel on Climate Change. We discussed the potential impact of climate change on water resources based on the results of GWLF simulations carried out using rainfall and temperature data from five general circulation models (GCMs). The simulation results indicate that river discharge in the wet season increases significantly, and decreases in the dry season. The discharge variations from using the various GCMs as inputs fall within the range of ?26 to +15 % for the dry season and ?10 to +82 % for the wet season. The variation in available water will seriously impact the first period rice farming (the period between the beginning of January and the end of May) in southern Taiwan. Consequently, effective reduction in conveyance loss in the irrigation canal systems and proper fallowing of paddy fields will be the main challenges to Taiwan’s agricultural sector for alleviating the impact of climate change. For further decision making, we show the effects of adapting to climate change by various degrees of the following two methods: fallowing paddy fields to various degrees and reducing conveyance loss in irrigation canal systems.     

Interval number fuzzy linear programming for climate change impact assessments of reservoir active storage

The major uncertainty in the climate change impact study inherits from applying the predictions of General Circulation Models (GCMs). Different results might be obtained by using various GCMs’ predictions, which causes difficulties on the decision making of water resources management. This study proposed an integrated hydrological simulations and optimization framework, consisting of a fuzzy linear programming model with interval numbers, a streamflow simulation model, and agricultural water demand projections, to evaluate the impacts of climate change on reservoir active storage. The reservoir inflows are simulated by the WatBal model, while agricultural water demands are predicted based on the projected change of potential evapotranspiration. Inflows and water demands are used to formulate an interval number fuzzy linear programming model. Fuzzy relationships are used to describe tolerable deficits of water resources, and the interval number is employed to indicate ranges of possible inflows and water demands. This systematic framework is applied to study the Tsengwen reservoir watershed to provide an optimal interval of active storage. The results further indicate the higher tolerable deficit, the smaller difference between superior and inferior active storage.     

Is long-term climate change beneficial or harmful for rice total factor productivity in Japan: evidence from a panel data analysis

Under global warming, influences of heat stress and flooding on rice production are becoming critical in Japan, but it is still under discussion whether future climate change is beneficial or harmful for Japanese rice production. This study aims to evaluate the impacts of long-term climate change on rice total factor productivity (TFP) by a panel data analysis. We estimate a regression model to link rice TFP to climate factors via yield, quality, and flood influence by using crop models, and then project future TFP levels from the results of the high-resolution model for interdisciplinary research on climate (MIROC). The results demonstrate that climate change has a positive effect in the northern regions, such as Hokkaido and Tohoku, but it decreases rice TFP in other regions, especially in the western regions, after the 2050s. Furthermore, climate change increases fluctuations in rice TFP of the western regions. To overcome negative impacts, a forward shift in the rice transplanting time is effective. Second, the potential impacts of climate factors, shown by the elasticity values of rice TFP, are 0.18 (via yield), 0.09 (via quality), and ?0.03 (via flood influence), but these climate impacts are weaker than socio-economic factors, such as economies of scale and research and development capital stocks. Third, regional gaps in rice TFP are enlarged over time because of different impacts of climate factors as well as socio-economic factors. Such fact-findings can be used to reconsider agricultural policy.     

Is long-term climate change beneficial or harmful for rice total factor productivity in Japan: evidence from a panel data analysis

Under global warming, influences of heat stress and flooding on rice production are becoming critical in Japan, but it is still under discussion whether future climate change is beneficial or harmful for Japanese rice production. This study aims to evaluate the impacts of long-term climate change on rice total factor productivity (TFP) by a panel data analysis. We estimate a regression model to link rice TFP to climate factors via yield, quality, and flood influence by using crop models, and then project future TFP levels from the results of the high-resolution model for interdisciplinary research on climate (MIROC). The results demonstrate that climate change has a positive effect in the northern regions, such as Hokkaido and Tohoku, but it decreases rice TFP in other regions, especially in the western regions, after the 2050s. Furthermore, climate change increases fluctuations in rice TFP of the western regions. To overcome negative impacts, a forward shift in the rice transplanting time is effective. Second, the potential impacts of climate factors, shown by the elasticity values of rice TFP, are 0.18 (via yield), 0.09 (via quality), and −0.03 (via flood influence), but these climate impacts are weaker than socio-economic factors, such as economies of scale and research and development capital stocks. Third, regional gaps in rice TFP are enlarged over time because of different impacts of climate factors as well as socio-economic factors. Such fact-findings can be used to reconsider agricultural policy.

     

Methodologies for simulating impacts of climate change on crop production

Ecophysiological models are widely used to forecast potential impacts of climate change on future agricultural productivity and to examine options for adaptation by local stakeholders and policy makers. However, protocols followed in such assessments vary to such an extent that they constrain cross-study syntheses and increase the potential for bias in projected impacts. We reviewed 221 peer-reviewed papers that used crop simulation models to examine diverse aspects of how climate change might affect agricultural systems. Six subject areas were examined: target crops and regions; the crop model(s) used and their characteristics; sources and application of data on [CO₂] and climate; impact parameters evaluated; assessment of variability or risk; and adaptation strategies. Wheat, maize, soybean and rice were considered in approximately 170 papers. The USA (55 papers) and Europe (64 papers) were the dominant regions studied. The most frequent approach used to simulate response to CO₂ involved adjusting daily radiation use efficiency (RUE) and transpiration, precluding consideration of the interacting effects of CO₂, stomatal conductance and canopy temperature, which are expected to exacerbate effects of global warming. The assumed baseline [CO₂] typically corresponded to conditions 10-30 years earlier than the date the paper was accepted, exaggerating the relative impacts of increased [CO₂]. Due in part to the diverse scenarios for increases in greenhouse gas emissions, assumed future [CO₂] also varied greatly, further complicating comparisons among studies. Papers considering adaptation predominantly examined changes in planting dates and cultivars; only 20 papers tested different tillage practices or crop rotations. Risk was quantified in over half the papers, mainly in relation to variability in yield or effects of water deficits, but the limited consideration of other factors affecting risk beside climate change per se suggests that impacts of climate change were overestimated relative to background variability. A coordinated crop, climate and soil data resource would allow researchers to focus on underlying science. More extensive model intercomparison, facilitated by modular software, should strengthen the biological realism of predictions and clarify the limits of our ability to forecast agricultural impacts of climate change on crop production and associated food security as well as to evaluate potential for adaptation.     

RCPs情景下福建省水稻生产的适应性调整模拟研究

【目的】气候变化对农业生产的影响日趋明显。分析未来气候变化所产生的影响,模拟调整作物耕作和栽培措施,为有效减轻未来气候变化带来的负效应提供参考。【方法】根据联合国政府间气候变化专门委员会第5次工作报告中未来可能的温室气体排放情况,以BCC_CSM模式模拟未来的气候变化情景,选取RCP4.5和RCP8.5两种典型浓度路径情景,与作物模型CERES-Rice耦合,筛选出了未来气候变化条件下福建省各稻区可能的最佳品种和播期,并研究分析了品种更替和播期调整后的水稻单产、稳产性以及全省水稻总产的变化。【结果】在RCP4.5和RCP8.5情景下,闽东南双季稻区早稻的模拟产量较未作适应性调整分别增加1.6%和1.9%,晚稻的模拟产量依次增加13.5%和9.8%;闽西北双季稻区早稻的模拟产量依次提高1.4%和1.0%,晚稻的模拟产量依次提高11.5%和7.9%;闽西北山地单季稻区一季稻的模拟产量分别增加14.1%和13.7%。在综合考虑两种适应性措施后,福建省各稻区总产也较当前明显提高,在RCP4.5和RCP8.5两种情景下,分别提高9.3%和10.5%。【结论】未来气候变化对福建省水稻产量有不利影响,可采取一定的适应性措施缓解负效应。     

川滇交界干热河谷地区农业气候资源特征

利用四川攀枝花和云南华坪、元谋等3个时间序列较长的气象站地面观测资料,运用线性趋势法、气候倾向率法、Mann-Kendall非参数统计检验法等方法分析了川滇交界干热河谷地区光能、热量、水分和风能等农业气候资源特征。结果表明：川滇干热河谷地区光能资源丰富,热量资源充足,风能资源良好,但水分资源结构不平衡,易出现干旱。并且在全球气候变化背景下,光能、热量、水分和风能等农业气候资源都发生了明显的变化,对农业会造成一定的影响,如温度升高导致作物生长期延长,生长季热量增加,适宜种植范围扩大。≥10 ℃积温的增加为热量要求较高的热带经济作物种植提供了有利条件,川滇干热河谷地区适宜热带经济作物种植区域将增加。此外,农业气候资源的变化也会带来一定的负面影响,如冬季温度升高,将导致热带作物抗旱能力下降等。     

高温胁迫对玉米关键生育期生理特性和产量的影响研究进展

以气候变暖及极端气候为主要特征的全球气候变化,会对农业生产产生重大影响,甚至威胁全球粮食安全。随着技术进步和社会对粮食需求的改变,玉米已成为中国第一大粮食作物。高温胁迫对玉米生理生化特征及生长发育产生不利影响,导致玉米产量和品质降低。本文对高温胁迫对与产量相关的玉米器官的生理生化影响和不同生育期高温胁迫对玉米生长及产量的影响进行综述。高温胁迫对玉米细胞膜及抗氧化系统、叶片光合作用及相关酶活性、雄穗分支分化及花粉活力、雌穗吐丝及花丝活力、子粒内淀粉合成相关酶活性均有负面影响;不同生育期高温胁迫对产量及产量构成有不同程度影响,玉米生育期对高温胁迫的敏感程度由高到低分别为开花期灌浆期穗期苗期。同一生育期高温胁迫在不同玉米品种间亦有较大差异。     

The Changing Global Environment and World Crop Production

Summary

During a period of a presumed world food crisis, the importance of climate and weather, and the rising level of atmospheric carbon dioxide are highlighted as important changes in the global environment. There is a dual and simultaneous effect of the rising level of atmospheric carbon dioxide on first, global warming and second, on the enhancement of crop productivity as reflected by an increased photosynthetic capacity, greater water use efficiency and alleviation of other crop stresses. Climate variability has a greater impact on agricultural productivity than does climate change. The rising level of atmospheric carbon dioxide is a universally free subsidy, gaining in magnitude with time, on which all can reckon when it comes to crop productivity.     

Impacts of climate change on rice market and production capacity in the Lower Mekong Basin

The supply of water is affected by climate changes. In addition, high economic growth in the lower Mekong River countries including two large rice exporters is expected to reduce the per capita consumption of rice as incomes grow. Consequently, the need exist to investigate changes in supply and demand using econometric models of rice markets in the countries, where water supplies are expected to change. The objective of this research is to clarify impacts of water supply changes on rice producers and consumers using supply and demand models of rice considering changes in the water supply to aid in producing agricultural policies and plans. The following two simulations were conducted in this assessment: (a) baseline and (b) CC_B2. The simulation of the baseline includes the assumption that the evapotranspiration (ET) of each province after 2000 is the average quantity of ET from 1995 to 1999. The simulation of the CC_B2 includes the assumptions that ET of each province after 2010 accords with the IPCC socioeconomic scenario B2. The simulation results suggest that climate change will depress wet season rice production in Cambodia and Mekong River Delta (MRD) region in Vietnam, and that of dry season rice in the MRD region in Vietnam and northeastern region (Isan) Thailand. The simulation results also indicate that climate change will increase farm prices of rice in Cambodia, Vietnam, and Thailand. The results suggest that climate changes will weigh on the livelihood of rice consumers, especially those of poor rural populations.

     

Impacts of climate change on rice market and production capacity in the Lower Mekong Basin

The supply of water is affected by climate changes. In addition, high economic growth in the lower Mekong River countries including two large rice exporters is expected to reduce the per capita consumption of rice as incomes grow. Consequently, the need exist to investigate changes in supply and demand using econometric models of rice markets in the countries, where water supplies are expected to change. The objective of this research is to clarify impacts of water supply changes on rice producers and consumers using supply and demand models of rice considering changes in the water supply to aid in producing agricultural policies and plans. The following two simulations were conducted in this assessment: (a) baseline and (b) CC_B2. The simulation of the baseline includes the assumption that the evapotranspiration (ET) of each province after 2000 is the average quantity of ET from 1995 to 1999. The simulation of the CC_B2 includes the assumptions that ET of each province after 2010 accords with the IPCC socioeconomic scenario B2. The simulation results suggest that climate change will depress wet season rice production in Cambodia and Mekong River Delta (MRD) region in Vietnam, and that of dry season rice in the MRD region in Vietnam and northeastern region (Isan) Thailand. The simulation results also indicate that climate change will increase farm prices of rice in Cambodia, Vietnam, and Thailand. The results suggest that climate changes will weigh on the livelihood of rice consumers, especially those of poor rural populations.     

发展海南低碳高效农业的几点思考

气候变暖已经成为世界生态恶化的首要原因，因此，以低能耗、低排放、低污染为特征的低碳经济是目前人类应对全球气候变化，减缓温室气体排放的根本出路。农业生产与全球气候变化息息相关，低碳农业将成为今后农业发展的方向和目标。在此背景下，探索性地提出海南发展低碳高效农业的一些思考，在分析海南发展低碳高效农业的优势和制约因素的基础上，提出海南发展低碳高效农业的一些建设性的思路和建议。     

Minor components and wheat quality: Perspectives on climate changes

Minor compounds of cereal grains such as lipids and cell wall polysaccharides play an important role in their milling properties, their transformation into baked cereal products and their nutritional properties. These effects are mainly due to their interactive properties, such as their ability to absorb large amounts of water for polysaccharides or to interact with starch polymers and proteins for lipids. Environmental stress induced by climate change and regulations for environmentally friendly agriculture can interfere with the biosynthesis of these minor grain compounds as well as the main compounds starch and protein. Indeed, the metabolic networks of all components of the endosperm of grains are closely associated. Therefore, in the context of climate change and agricultural sustainability, lipids and cell wall polysaccharides may be affected. Contrasting with a plethora of studies reporting the impact of environment and fertilizer on cereal proteins, there is a real lack of information on this particular topic for these minor compounds. However, our knowledge of the physico-chemical properties and biosynthesis of these minor compounds allows us to assess the likely strong impact of environmental and agronomic constraints on the relationships between cell wall polysaccharides, lipids and cereal quality.     

海南省热带农产品营销体系现状及改进建议

海南省作为一个中国热带农产品的重要生产地区,农业资源非常丰富。由于地理和气候的影响,很多热带农产品在整个营销体系中面临着环节多、成本高等问题;同时,岛内的营销模式种类繁多,并无统一标准,而且各种热带农产品在营销过程中的信息化程度不高,因此在管理过程中面临诸多问题。海南省每年易受各种自然灾害和人为因素影响,导致热带农产品会在某些特定时段出现“菜贱伤农”和“菜贵伤农”的情况。基于以上情况,本文明确热带农产品营销体系的概念和目标,分析了海南省农产品营销体系的现状,并与国内外发达的国家与地区进行对比,提出海南省热     

Changing global risk of invading greenbug Schizaphis graminum under climate change

The geographical range, abundance, growth rate, survival and mortality of insects are largely influenced by abiotic factors such as temperature and humidity. When suitable, these factors can positively influence the abundance of insect pests. It is in this light that the influence of climate change, particularly global warming, has direct bearing to crop protection. In this study, we simulated the potential distribution of the greenbug or wheat aphid Schizaphis graminum (Rondani) (Aphididae), a major global pest of wheat, using the climate matching tool CLIMEX (CLIMatic indEX) in global warming scenarios. To predict the potential distribution of the insect on CLIMEX at time periods 2030, 2070 and 2100, we utilize two global climate models (GCMs) at two emission scenarios. The result of CLIMEX modelling shows that the favourable climatic areas for S. graminum are subtropical to temperate at the current time. With global warming, under different scenarios current suitable and highly suitable areas in the northern hemisphere are expected to expand to higher latitudes by 2030 towards 2100; while areas in the southern hemisphere, where the pest’s living areas already have high temperature ranges, the occurrence of the pest will contract by 2030 since temperatures will exceed its heat limits. This study assists in predicting the potential risk areas that may be threatened by this pest in the future, providing supportive information for agricultural management practices and aid in the preparation of strategic plans to avoid possible economic damage posed by future expansion of the pest population due to climate change.     

福建省2008-2009年度冬季气候对农业生产的影响

福建省2008-2009年度冬季总体农业气候特征表现为大部分地区气温偏高,降水量偏少,日照时数正常到一般偏多;发生了3次对农业有影响的寒潮降温过程;出现了时间长、范围广的秋冬气象干旱,尤其是南部地区。对农业生产而言,大部分时段光温条件良好,有利于作物和果树的光合生长,作物长势基本正常;3次主要的寒潮降温过程造成的寒冻害对农牧业造成了较重的经济损失;秋冬气象干旱对缺乏灌溉条件的农作物生长极其不利。