Comparison of regional climate scenario data by a spatial resolution for the impact assessment of the uncertainty associated with meteorological inputs data on crop yield simulations in Korea

Uncertainty of crop yield simulation would be affected by weather input data prepared from different sources of climate datasets. Although regional climate data at a high spatial resolution would be useful for the impact assessment of climate change on crop production, little effort has been made to characterize the uncertainty associated with such climate data in terms of crop yield simulations. The objectives of this study were to compare climate scenario data products obtained from a series of downscaling processes and to identify an overall pattern of uncertainty in these climate data in terms of crop yield simulation. Regional climate scenario data from 2011 to 2014 had a spatiotemporal pattern of uncertainty, which differed by meteorological variables and spatial resolution. Overall, the uncertainty of daily minimum temperature was greater than that of maximum temperature. Daily minimum temperature also had relatively greater uncertainty in an early season of crop production, which could result in the cumulative impact on the uncertainty of crop yield simulations. For the uncertainty of climate data at different spatial resolution, climate data at higher spatial resolution, e.g. 1 km, tended to have lower uncertainty than data at resolution of 12.5 km did. Still, the uncertainty of regional climate data was relatively similar between data at resolution of 12.5 km and 1 km in major rice production areas in Korea except in areas near Seosan. This merits further studies to examine actual differences in projected crop yields using regional climate scenario data in the future and to assess the impact of uncertainty associated with regional climate data on crop yield simulation.     

近48年来渭北旱塬气候变化对苹果生长的影响

通过咸阳、渭南、宝鸡及铜川渭北地区1960-2007年月平均气温和月平均降水资料,及陕西渭北旱塬地区苹果生长期的相关气象资料。运用Excel分析近48年来苹果生长物候期：萌芽期（2-3月）、开花期（4月）、果实膨大期（5-8月）、果实着色期（9月）、果实成熟期（10月）的平均气温及降水量变化。研究表明：陕西渭北旱塬气温的变化趋势基本上同全国气温的变化趋势一致。近48年来渭北旱塬地区气温总体呈上升趋势,而降水量减少。这种气候变化趋势使得同一时期不同年份的平均气温和降水量对苹果生长期的影响有所不同。（1）萌芽期低温少水,使得果树解除休眠期、叶芽、花芽萌动和开花等物候期有了明显的不同。（2）开花期气温的变化影响最大。（3）果实膨大期气温和降水量的变化直接影响苹果数量。（4）果实着色期低温,天气晴好,降水量少有利于果实着色。（5）果实成熟期气温高,降水量少有利于果实成熟采收。     

山西中北部春玉米生长季土壤水分动态及对产量的影响

为了掌握土壤水分与玉米生长发育内在关系,提高土壤水分利用率,统筹调配水资源和防灾减灾提供理论依据,利用1994—2010年山西省忻州市忻府区农业气象观测站春玉米生长季0~50 cm土壤水分和玉米产量观测资料,分析了玉米生长季土壤水分变化规律及对玉米产量的影响。结果表明：春玉米生长季土壤水分年际变化振荡明显,呈多波动变化,与年降水量相关显著;一年中土壤水分变化分为水分消耗期、水分补给期和水分平稳期3个阶段;土壤水分的垂直变化明显,在20~30 cm层含水量最大,0~20 cm为多变层,20~50 cm为缓变层,雨季土壤水分变化较干季复杂;玉米拔节—乳熟期土壤贮水量与气候产量呈正相关,抽雄期是需水临界期,此时0~50 cm土壤贮水量每增加10 mm,产量增加200~250 kg/hm²。     

Application of the CSM-CERES-Maize model for planting date evaluation and yield forecasting for maize grown off-season in a subtropical environment

In recent years, maize has become one of the main alternative crops for the Autumn–Winter growing season (off-season) in several regions of Brazil. Water deficits, sub-optimum temperatures and low solar radiation levels are some of the more common problems that are experienced during this growing season. However, the impact of variable weather conditions on crop production can be analyzed with crop simulation models. The objectives of this study were to evaluate the Cropping System Model (CSM)-CERES-Maize for its ability to simulate growth, development, grain yield for four different maturity maize hybrids grown off-season in a subtropical region of Brazil, to study the impact of different planting dates on maize performance under rainfed and irrigated conditions, and for yield forecasting for the most common off-season production system. The CSM-CERES-Maize model was evaluated with experimental data collected during three field experiments conducted in Piracicaba, SP, Brazil. The experiments were completely randomized with three replications for the 2001 experiment and four replications for the 2002 experiments. For the yield forecasting application, daily weather data for 2002 were used until the forecast date, complemented with 25 years of historical daily weather data for the remainder of the growing season. Six planting dates were simulated, starting on February 1 and repeated every 15 days until April 15. The evaluation of the CSM-CERES-Maize showed that the model was able to simulate phenology and grain yield for the four hybrids accurately, with normalized RMSE (expressed in percentage) less than 15%. The planting date analysis showed that a delayed planting date from February 1 to April 15 caused a decrease in average yield of 55% for the rainfed and 21% for the irrigated conditions for all hybrids. The yield forecasting analysis demonstrated that an accurate yield forecast could be provided at approximately 45 days prior to the harvest date for all four maize hybrids. These results are promising for farmers and decision makers, as they could have access to accurate yield forecasts prior to final harvest. However, to be able to make practical decisions for stock management of maize grains, it is necessary to develop this methodology for different locations. Future model evaluations might also be needed due to the release of new cultivars by breeders.     

Application of the CSM-CERES-Maize model for planting date evaluation and yield forecasting for maize grown off-season in a subtropical environment

In recent years, maize has become one of the main alternative crops for the Autumn–Winter growing season (off-season) in several regions of Brazil. Water deficits, sub-optimum temperatures and low solar radiation levels are some of the more common problems that are experienced during this growing season. However, the impact of variable weather conditions on crop production can be analyzed with crop simulation models. The objectives of this study were to evaluate the Cropping System Model (CSM)-CERES-Maize for its ability to simulate growth, development, grain yield for four different maturity maize hybrids grown off-season in a subtropical region of Brazil, to study the impact of different planting dates on maize performance under rainfed and irrigated conditions, and for yield forecasting for the most common off-season production system. The CSM-CERES-Maize model was evaluated with experimental data collected during three field experiments conducted in Piracicaba, SP, Brazil. The experiments were completely randomized with three replications for the 2001 experiment and four replications for the 2002 experiments. For the yield forecasting application, daily weather data for 2002 were used until the forecast date, complemented with 25 years of historical daily weather data for the remainder of the growing season. Six planting dates were simulated, starting on February 1 and repeated every 15 days until April 15. The evaluation of the CSM-CERES-Maize showed that the model was able to simulate phenology and grain yield for the four hybrids accurately, with normalized RMSE (expressed in percentage) less than 15%. The planting date analysis showed that a delayed planting date from February 1 to April 15 caused a decrease in average yield of 55% for the rainfed and 21% for the irrigated conditions for all hybrids. The yield forecasting analysis demonstrated that an accurate yield forecast could be provided at approximately 45 days prior to the harvest date for all four maize hybrids. These results are promising for farmers and decision makers, as they could have access to accurate yield forecasts prior to final harvest. However, to be able to make practical decisions for stock management of maize grains, it is necessary to develop this methodology for different locations. Future model evaluations might also be needed due to the release of new cultivars by breeders.     

大兴安岭蓝莓生长气候条件分析

为了解1971—2014年大兴安岭地区蓝莓生长季平均气温的分布规律和变化趋势及对气候变化响应,利用大兴安岭地区6个气象站气温资料,采用EOF、小波分析和文献综述等方法,研究蓝莓生长季平均气温时空变化,主要气象灾害及其对气候变化响应。结果表明:大兴安岭地区蓝莓生长季平均气温呈增加趋势,周期变化存在28年和8年尺度;空间分布展现为第1特征向量正变化,第2和第3特征向量正、负相间变化;特征向量东南与西北变化相反,东与西也相反;气候变化将对蓝莓产生一定的影响,利弊均有。热量条件影响下蓝莓的气象灾害主要有寒害、霜冻和春季低温阴雨寡照天气并阐述发生情况及影响。研究结果可为确保蓝莓优质高产、避免灾害损失和科学规划提供理论参考。     

Effect of intermittent drought on grain yield and quality of rice (Oryza sativa L.) grown in Rwanda

The climate change will contribute drought and temperature extremes to rice growing systems, especially when cultivated in equatorial regions. To evaluate opportunities to cultivate and breed drought-tolerant rice, seven rice cultivars were evaluated in Rwanda for recurring morphological drought scores, grain yield and components, and quality characteristics. The cultivation conditions, that is site and drought treatment, impacted morphological drought scores, growth and yield attributes, while cultivar affected quality attributes. Thus, site showed a higher impact on grain yield and components than drought and cultivar, with generally a reduced grain yield at the low-temperature site, as a result of low spikelet fertility. Morphological drought scores were generally increased by drought, while drought at the reproductive stage at the high-temperature site was negative for yield and its components. The cultivars “Intsindagirabigega” and “Jyambere” were adapted to high-temperature site conditions. The cultivar “Intsindagirabigega” had the highest amylose content, and “Mpembuke,” the highest antioxidant capacity. Thus, climate change with increased temperature and drought extremes may increase rice productivity in cool areas, while especially drought at reproductive stage will be detrimental in low altitude areas with high temperature. Cultivar variation indicated opportunities for selection and breeding of climate change tolerant rice cultivars which should be of immediate priority.     

湿地气候对周边区域粮食生产的影响—黑龙江省七星河湿地国家自然保护区为例

为了研究湿地气候对粮食生产的影响,达到增产目的。以七星河湿地国家自然保护区为例,利用1961—2008年湿地年平均气温、降水和周边3乡1场粮食总产、单产资料。采用趋势分析,粮产分解,相关系数计算等方法分析粮产趋势变化和湿地气候对周边场、乡粮食生产影响。结果表明：五九七农场在粮食总产、单产和增速方面排在第一位,第二位是青原镇,第三位是尖山子乡,最后一位是七星河乡。说明距离湿地远近对粮产有一定影响,四地粮产特别是五九七粮食增减变化对湿地降水变化有着较好的响应,旱年、降水偏少年粮食增产,反之,大涝、降水偏多的年份减产。同时气温变化对当年粮食产量影响较大,对粮产的趋势Y_w增加或减少影响弱一些,而降水变化对Y_w产量增加或减少的影响是主要的。由此可见,湿地气候冷湿性对周边粮食生产影响是不利的。尤其是通过近10年气候及粮产实际监测表明,实验结果与上述结论是一致的。应采取治涝措施,加强农田基本建设,发展生态农业,做到旱涝保收。     

Impacts and adaptation of the cropping systems to climate change in the Northeast Farming Region of China

The Northeast Farming Region of China (NFR) is a very important crop growing area, comprising seven sub-regions: Xing’anling (XA), Sanjiang (SJ), Northwest Songliao (NSL), Central Songliao (CSL), Southwest Songliao (SSL), Changbaishan (CB) and Liaodong (LD), which has been severely affected by extreme climate events and climatic change. Therefore, a set of expert survey has been done to identify current and project future climate limitations to crop production and explore appropriate adaptation measures in NFR. Droughts have been the largest limitation for maize (Zea mays L.) in NSL and SSL, and for soybean (Glycine max L. Merr.) in SSL. Chilling damage has been the largest limitation for rice (Oryza sativa L.) production in XA, SJ and CB. Projected climate change is expected to be beneficial for expanding the crop growing season, and to provide more suitable conditions for sowing and harvest. Autumn frost will occur later in most parts of NFR, and chilling damage will also decrease, particularly for rice production in XA and SJ. Drought and heat stress are expected to become more severe for maize and soybean production in most parts of NFR. Also, plant diseases, pests and weeds are considered to become more severe for crop production under climate change. Adaptation measures that have already been implemented in recent decades to cope with current climatic limitations include changes in timing of cultivation, variety choice, soil tillage practices, crop protection, irrigation and use of plastic film for soil cover. With the projected climate change and increasing risk of climatic extremes, additional adaptation measures will become relevant for sustaining and improving productivity of crops in NFR to ensure food security in China.     

内蒙古西部地区自然灾害对玉米产量影响及气象因子分析

为明确内蒙古自治区玉米产量受灾害性天气影响情况,根据内蒙古自治区2005-2017年自然灾害情况、玉米播种面积、单产和总产情况,分析气象灾害影响和减产情况.结果表明:旱灾造成的内蒙古受灾面积占到70％以上,灾害发生频率最多、产生影响最大,且旱灾导致2009年玉米单产水平为近年最低.分析内蒙古自治区西部地区4个地市的23...     

基于作物模型的冬小麦气候适宜度算法研究

为了定量分析气象条件对作物生长的综合影响,利用WOFOST作物生长模型分析冬小麦各生育期的气候适宜度。通过对华北地区3个代表站点2007—2009年生长季的冬小麦进行生长模拟,并选取2007—2008年生长季的模拟结果作为标准,以其他年份同一生育期的生物量与标准的比值作为该生育期的气候适宜度,并与统计方法的结果进行对比。结果表明,用作物模型计算得到的适宜度与产量之间呈现出较好的正相关性,决定系数为0.603,且通过了0.05置信水平检验,可用该方法对冬小麦气候适宜度进行估算。     

1951—2012年河南省气候变化对冬小麦和玉米产量的影响

在分析河南省1951—2012 年历史气候变化背景下,对冬小麦和玉米不同生长时期对应的气候要素变化对其产量的影响进行定量研究。利用国家气象局网站提供的历史气象数据,基于Matlab 和Surfer 8.0 绘制年平均气温和降水量的小波系数实部等值线图。通过用二次函数拟合趋势产量,将冬小麦和玉米的历年气象产量分离出来。之后利用SPSS进行逐步回归分析,建立以气候产量为因变量,不同生长时期的气候要素为自变量的回归模型。结果表明：（1）河南省年降水量在其变化过程中存在多时间尺度特征,小波波幅中心在36~58 年、15~35 年以及8~14 年这3 类时间尺度上正负交替出现,存在周期性的变化规律。在18 年尺度上,年均气温到2012 年处于升高状态。（2）冬小麦全生育期内,在其他自变量不变的情况下,越冬期降水量每增加1 mm,气象产量将减少0.221 万t;越冬期平均温度每增加1℃,气象产量将减少13.277万t;在冬小麦生长期第二阶段中,降水量每增加1 mm,气象产量将减少0.149万t。（3）在玉米全生育期内,保持其他自变量不变的前提下,营养生长期内降水量每增加1 mm,气象产量将减少0.003 万t;营养生长期平均温度每增加1℃,气象产量将减少6.389 万t;玉米生殖生长期间,降水量每增加1 mm,气象产量将减少0.159 万t。从总体上来看,温度和降水变化对气象产量的影响皆为负面影响,并且温度变化对粮食产量的影响比降水变化产生的影响显著得多。通过对2 个回归模型进行对比发现冬小麦比玉米具有更强的气候变化敏感性。     

2001—2012年河南省夏玉米产量变化及生长季气象因子分析

为明确近年来河南省夏玉米产量变化及其与生长季（6—9月）灾害性天气发生规律的关系,统计了2001—2012年河南省农作物受灾面积,夏玉米总产、单产和种植面积,同时利用河南省不同纬度18个台站2001—2013年地面气候资料日值数据,分析了夏玉米生长季6—9月不同气象因子变化规律。结果表明,河南省近年来主要的灾害性天气为干旱、渍涝和风灾;玉米总产的增加主要在于近年来玉米种植面积的增加,单产水平一直处于5550 kg/hm²;玉米生长期,特别是灌浆期（8月）遭受阴雨寡照（低温）、高温干旱是造成玉米单产降低的主要原因之一;倒伏导致减产主要是在玉米灌浆中后期（8—9月）遇到大风灾害性天气。加强在玉米抵御自然灾害性天气能力方面的研究,是提高玉米单产和全面提升玉米生产能力的重要举措。     

Trade-off between wheat yield and drainage under current and climate change conditions in northeast Germany

In the temperate climate of northeast Germany, a trade-off exists between water use in agricultural crop production and groundwater recharge which is important for urban water supply, irrigation, forestry and peat protection. The APSIM-Nwheat model was used to analyze the impact of climate change scenarios on deep drainage (DD), the water loss below the maximum root zone as the main source of groundwater recharge, and wheat production for two main soil types. A linear and a nonlinear climate scenario were used in this study: The linear scenario for 2001–2050 was based on a simple linearly modified historical climate record from 1951 to 2000. The nonlinear scenario used the same 1951–2000 historical climate record but combined it nonlinearly with a Global Circulation Model climate scenario for 2001–2050. Simulation results showed different distributions of deep drainage and grain yield with the linear and nonlinear scenarios, but no difference in the 50-year averages. Hence, a linear manipulation of climate records can be as effective for climate change impact studies on deep drainage and grain yield as nonlinearly manipulated climate data, if long-term average changes are of main interest. The simulation results indicated that a trade-off between deep drainage and grain yields can be potentially controlled through N management. However, such control mechanism was more effective under current climate conditions than under future climate and on a better water-holding silt soil compared to a poorer water-holding loamy sand. It is suggested that areas with poor water-holding soils should be managed extensively for groundwater recharge harvesting while better water-holding soils should be used for high input grain production.     

气候变化对中国水稻生产的影响研究进展

水稻生产系统是响应气候变化最敏感的农业生态系统之一,本文综述了当前和未来气候变化对我国水稻生产的影响。气候变化背景下,我国水稻生长季的热量资源增多,辐射资源减少,降水不均一性加大。高温热害、干旱、暴雨和洪涝灾害发生更频繁,这可能降低水、热资源的有效性。气候变化使我国单季稻和双季稻潜在种植边界显著北移,导致单季稻、早稻和晚稻的主要生育期缩短。基于统计模型和水稻生长模型的研究结果表明,如果不考虑品种改良和栽培技术的进步,气候变化使单季稻、早稻和晚稻产量下降,但不同稻作区和方法间存在差异。我国水稻生产重心北移、实测生育期延长和产量增加的变化趋势,反映了水稻生产系统通过种植分布调整、品种改良和技术改进来适应气候变化的能力。未来气候变化将进一步导致水稻生育期缩短和产量下降,对我国水稻生产和粮食安全带来严峻挑战。仍需加强气候变化影响机制的研究及其在影响评估中的应用,减小影响评估的不确定性并增加其系统性,为制定有效的应对策略提供可靠的理论支持。     

Climate impacts on palm oil yields in the Nigerian Niger Delta

Palm oil production has increased in recent decades and is estimated to increase further globally. The optimal role of palm oil production, however, is controversial because of conflicts with other important land uses and ecosystem services. Local conditions and climate change affect resource competition and the desirability of palm oil production in the Niger Delta, Nigeria.The objectives of this study are to (1) establish a better understanding of the existing yield potentials of oil palm areas that could be used for integrated assessment models, (2) quantify for the first time uncertainties in yield potentials arising from the use of climate output data from different Global Circulation Models (GCM’s) with varied West African Monsoon (WAM) system representations forced to the same Regional Climate Models (RCM’s). We use the biophysical simulation model APSIM (Agricultural Production Systems Simulator) to simulate spatially variable impacts of climate change on oil palm yield over the Nigerian Niger Delta. Our results show that the impact of climate change on oil palm yield is considerable across our study region. The yield differences between the IPCC RCPs were small. The net impact of climate change on oil palm is positive and is dynamically inconsistent. There is no significant change in the simulated yield arising from the differences in the forcing’s data. We found the most effective strategy for oil palm yield optimization under climate change to be shifting of sowing dates and introduction of irrigation.     

Climate change impact on corn suitability in Isabela province,Philippines

Climate change is expected to affect agricultural crop production in the Philippines. Several studies were already done to quantify the effect of climate change on agricultural crop production in the country. Most of these studies focus only on the effect of climate change on crop yield. This study estimated the effect of climate change on the area (suitable area) for corn production. Using the Land Use Suitability Evaluation Tool (LUSET), change in corn suitability in the province of Isabela was estimated for the years 2050, 2060, and 2070. Based on the results, climate change will negatively impact corn suitability in the province. Decreasing trend in corn suitability rating was observed due to increasing temperature resulting to loss of highly suitable areas for corn production. For example, during the first cropping season the estimated average decreases in suitability scores due to an increase in temperature were 6.7, 11.4, and 20.7% in the years 2050, 2060, and 2070, respectively. These decreases in suitability resulted in the loss of 6,777 ha highly suitable areas for corn production.     

移栽期对红土晒烟生长发育和产质量的影响

为探索红土晒烟适宜的种植期和收获期,初步了解红土晒烟适宜的气候环境,设置不同的移栽时间,通过比较不同移栽期烟株的生长发育情况和产量、品质表现,结果表明,不同移栽期对红土晒烟的生长速度、生育期、产量、产值、内在化学成分以及香气品质都有影响。通过调整不同移栽时间,可以使烟株生长发育在较适宜的气候条件下,使其特点得以充分展现,从而为生产优质红土晒烟营造良好客观条件。试验认为在云南保山潞江坝的自然气候环境下,选择在1月上旬移栽,烟株大田生育期适中,烟叶成熟时间较集中,利于调制,不仅产量、产值高,香气品质也表现较好     

Potential impact of future climate change on sugarcane under dryland conditions in Mexico

Assessments of impacts of future climate change on widely grown sugarcane varieties can guide decision‐making and help ensure the economic stability of numerous rural households. This study assessed the potential impact of future climatic change on sugarcane grown under dryland conditions in Mexico and identified key climate factors influencing yield. The Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model was used to simulate sugarcane growth and yield under current and future climate conditions. Management, soil and climate data from farm sites in Jalisco (Pacific Mexico) and San Luis Potosi (Northeastern Mexico) were used to simulate baseline yields. Baseline climate was developed with 30‐year historical data from weather stations close to the sites. Future climate for three decadal periods (2021–2050) was constructed by adding forecasted climate values from downscaled outputs of global circulation models to baseline values. Climate change impacts were assessed by comparing baseline yields with those in future decades under the A2 scenario. Results indicate positive impacts of future climate change on sugarcane yields in the two regions, with increases of 1%–13% (0.6–8.0 Mg/ha). As seen in the multiple correlation analysis, evapotranspiration explains 77% of the future sugarcane yield in the Pacific Region, while evapotranspiration and number of water and temperature stress days account for 97% of the future yield in the Northeastern Region. The midsummer drought (canicula) in the Pacific Region is expected to be more intense and will reduce above‐ground biomass by 5%–13% (0.5–1.7 Mg/ha) in July–August. Harvest may be advanced by 1–2 months in the two regions to achieve increases in yield and avoid early flowering that could cause sucrose loss of 0.49 Mg ha^?1 month^?1. Integrating the simulation of pest and diseases under climate change in crop modelling may help fine‐tune yield forecasting.     

Consequences of climate change for European agricultural productivity, land use and policy

This paper reviews the knowledge on effects of climate change on agricultural productivity in Europe and the consequences for policy and research. Warming is expected to lead to a northward expansion of suitable cropping areas and a reduction of the growing period of determinate crops (e.g. cereals), but an increase for indeterminate crops (e.g. root crops). Increasing atmospheric CO₂ concentrations will directly enhance plant productivity and also increase resource use efficiencies.

In northern areas climate change may produce positive effects on agriculture through introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. Disadvantages may be an increase in the need for plant protection, the risk of nutrient leaching and the turnover of soil organic matter. In southern areas the disadvantages will predominate. The possible increase in water shortage and extreme weather events may cause lower harvestable yields, higher yield variability and a reduction in suitable areas for traditional crops. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification in the Mediterranean and southeastern parts of Europe.

Policy will have to support the adaptation of European agriculture to climate change by encouraging the flexibility of land use, crop production, farming systems etc. In doing so, it is necessary to consider the multifunctional role of agriculture, and to strike a variable balance between economic, environmental and social functions in different European regions. Policy will also need to be concerned with agricultural strategies to mitigate climate change through a reduction in emissions of methane and nitrous oxide, an increase in carbon sequestration in agricultural soils and the growing of energy crops to substitute fossil energy use. The policies to support adaptation and mitigation to climate change will need to be linked closely to the development of agri-environmental schemes in the European Union Common Agricultural Policy.

Research will have further to deal with the effect on secondary factors of agricultural production, on the quality of crop and animal production, of changes in frequency of isolated and extreme weather events on agricultural production, and the interaction with the surrounding natural ecosystems. There is also a need to study combined effects of adaptation and mitigation strategies, and include assessments of the consequences on current efforts in agricultural policy to develop a sustainable agriculture that also preserves environmental and social values in the rural society.