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Global climate changes have led to frequent and recurrent heat stress, which has seriously affected the world maize production. The experiment presented in this paper was carried out during the maize‐growing season in 2021 and 2022 at the Huang–Huai–Hai Region Maize Science and Technology Innovation Center (36°09′N, 117°09′E) in Tai'an, Shandong province, China. The test site is located in the semi‐humid warm temperate continental monsoon climate zone, soil is brown loam. We selected different heat‐sensitive maize varieties: heat‐tolerant variety Zhengdan 958 (ZD958) and heat‐sensitive variety Xianyu335 (XY335) to study the stress effects of high temperature on the development of tassel in the key stage of its differentiation (the 12‐leaf stage, V12). We found that exposure to heat stress during the V12 stage significantly reduced the tassel size and the anther dehiscence area, making it difficult to disperse pollen, thus effectively reducing pollen production. In addition, heat stress had significant negative effects on pollen development, resulting in deformed pollen and lower pollen viability and germination rate. Our results also showed that heat stress significantly increased the activities of key reactive oxygen species‐scavenging enzymes including superoxide dismutase, peroxidase and catalase, and that the malondialdehyde and H2O2 content in tassels exposed to heat stress were significantly higher than those control group, where it should be noted that for the XY335, these effects were more pronounced than for the ZD958. The endogenous hormone content of tassels exhibited a variety of responses. After heat stress, the zeatin and salicylic acid content in tassels of both maize varieties were significantly lower than those in the respective control groups, while the abscisic acid and gibberellin acid content were significantly higher. With respect to the jasmonic acid and 3‐indoleacetic acid content, the two maize varieties exhibited opposite responses: in tassels from ZD958 plants subjected to heat stress were higher than those in the respective control group, while in tassels from XY335 plants, they were lower. The observed changes in protective enzyme activities and endogenous hormone contents induced by heat stress significantly affected the development of maize tassels and significantly reduced the amount, activity and germination rate of pollen. [ABSTRACT FROM AUTHOR]

The paper purpose was to assess the impact of climate change on wheat, maize and sunflower yield in the period 2017-2021, using statistical data from National Institute of Statistics (NIS) and National Administration of Meteorology (NAM) and other sources. Comparison method was used to evaluate the deviations between the registered air temperatures and precipitations and the 1981-2010 climatological norm. Graphic method reflected the dynamics of monthly air temperatures and rainfalls in each year. Descriptive statistics for mean, standard deviation and coefficient of variation reflected an more comprehensive image upon air temperature, precipitations and yield. Correlations and regression equations were used to establish the intensity of the kinks between climate factors and yield. The highest average air temperature In Romania was 12.130C in 2019. In the period 2017-2020, the average annual temperatures exceeded the climatological norm 1981-2010 accounting for 9.10C. The lowest rainfalls, 614.2 mm, were recorded in 2019, being below of 633.1 mm the norm for the period 1981-2010. The high temperatures associated with drought and low precipitations have deeply affected yield of many agricultural crops, including maize, wheat and sunflower. The highest wheat yield 4,888 kg/ha was achieved in 2017, and the lowest one, 2,966 kg/ha in 2020. Maize registered the highest performance of 7,644 kg/ha in 2018, and the lowest one, 3,977 kg/ha in 2020. Sunflower carried out the high performance 3,041 kg/ha in 2018, and the lowest one, 1,858 kg/ha in 2020. The worst agricultural years for these three crops was 2020, but 2017 favored wheat, while 2018 favored maize and sunflower. The correlation coefficient had in general small values between average temperature and yield, but a higher link with precipitations level. The multiple correlation between yield, air temperatures and precipitations was: r= 0.817 for wheat, r = 0.116 for maize and r = 0.504 for sunflower. In the South Eastern Dobrogea, the driest area in Romania, the rainfalls declined by 65% in the period 2018-2020 having a deep negative impact on sunflower seeds yield, which decreased from 4,282 kg/ha in 2018, to 1,503 kg/ha in 2020. The correlation between precipitations and sunflower yield positive and very strong (r = 0.737). As a conclusion, the climate conditions should be analyzed in each farm and farmers have to take measure to adapt the technologies for sustaining production. [ABSTRACT FROM AUTHOR]

The paper refers to the soils in Giarmata, Timiș County, the occupied areas and the way of use, presenting the main limiting factors and the classification in quality and fertility classes of the main agricultural crops in the current context of climatic changes. The objectives referred to: description and presentation of the soil and climatic conditions of the area; presentation of the main soil types in the Giamata area and description of those taken in the study; listing the main classes of quality, respectively fertility; determination of limiting factors and description of the processes taking place; description of soil types on which the research has been carried out; classification of land in quality classes according to the credit marks obtained for the main agricultural crops (maize, wheat, barley and sunflower) during 2021-2022. The studied material refers to the identification, presentation and description of the main types of soils identified in this area, namely: preluvosols, alluvials, chernozems, vertosols, pelosols, gleysols and stagnosols. Giarmata commune is located in the central-northern part of Timis County, at a distance of 11 km from Timişoara and 1.3 km from Timişoara International Airport. The locality is situated at an altitude between 100 and 150 m, with a weak fragmentation and low relief energy, occupying a total area of 7150 ha, of which 6292 ha represents agricultural land and 43.5 ha forest. The studies were carried out on 158 ha, divided into 5 plots, with areas between 22 and 43 ha. The main crops were maize (83 ha), wheat (44 ha), sunflower (20 ha and barley (8 ha). The lowest average temperature was recorded in February, 2021, namely -2.0°C. The absolute minimum temperature during the same period was -27.2°C on 16 February 2021. [ABSTRACT FROM AUTHOR]

Due to global climate change, droughts are likely to become more frequent and more severe in many regions such as in South Africa. In Limpopo, observed high climate variability and projected future climate change will likely increase future maize production risks. This paper evaluates drought patterns in Limpopo at two representative sites. We studied how drought patterns are projected to change under future climatic conditions as an important step in identifying adaptation measures (e.g., breeding maize ideotypes resilient to future conditions). Thirty-year time horizons were analyzed, considering three emission scenarios and five global climate models. We applied the WOFOST crop model to simulate maize crop growth and yield formation over South Africa's summer season. We considered three different crop emergence dates. Drought indices indicated that mainly in the scenario SSP5-8.5 (2051–2080), Univen and Syferkuil will experience worsened drought conditions (DC) in the future. Maize yield tends to decline and future changes in the emergence date seem to impact yield significantly. A possible alternative is to delay sowing date to November or December to reduce the potential yield losses. The grain filling period tends to decrease in the future, and a decrease in the duration of the growth cycle is very likely. Combinations of changed sowing time with more drought tolerant maize cultivars having a longer post-anthesis phase will likely reduce the potential negative impact of climate change on maize. [ABSTRACT FROM AUTHOR]

Drought stress is among the significant forms of abiotic stresses that unfavourably affects maize survival as well as the development from germination to maturity. This paper, therefore, reviewed drought stress effects in maize plants and expatiated on the plausible adoptable mitigation measures to employ in curbing these effects as well. Water shortage prompts drought stress that alters the morphological, physiological and biochemical activities in maize plants. The major drought stress implications on the plant's survival are mostly in the area of altered metabolic functions, including nutrient metabolism, cell membrane integrity, water relationships, plant yield, photosynthetic processes, osmotic adjustment, and the pigment content. Mitigating strategies, such as the breeding of drought-tolerant varieties, genomic applications for drought tolerance enhancement in maize plants, as well as the use of rhizobacteria and endophytic bacteria, can be employed in alleviating drought stress and ensuring optimal maize productivity. [ABSTRACT FROM AUTHOR]

Agricultural practices of smallholder farming systems of Latin America can play an important role in reducing their exposure to the risks associated with climate extremes. To date, however, there is no systematic analysis of scientific evidence for the extent to which these practices can provide the multiple benefits needed for smallholders to adapt to climate extremes. In this paper, we searched scientific databases to review scientific evidence of the benefit provided by twenty-six practices in crops commonly farmed by smallholders in the region and highly relevant for their food and nutrition security; namely, coffee, maize and beans. We reviewed scientific documents (n = 304) published in the period 1953–2021 to register evidence of the practices' effects on fifty-five benefits. Our analysis of these documents found measurement records (n = 924) largely based on field experiments (85%). Our results show strong evidence of the multiple benefits that some ecosystem-based practices (e.g., tree-based practices for coffee and no tillage for maize) can provide to support the adaptation to climate extremes of smallholder farming systems and enhance a farm's natural assets (e.g., biodiversity, water, soil). We also found that the majority of research on practices in the region focused more on the socioeconomic dimension (54%) rather than on the capacity of practices to improve the natural assets of a smallholder farmers or reduce the impact of climate extremes. Given these knowledge gaps, we discuss the importance of a renovated investment in research to address existing knowledge gaps. Our concluding suggestions for future research include the need for systematizing existing knowledge from different sources (e.g., peer-reviewed, gray literature, farmers, extension agencies, etc.), and to assess the extent to which these practices can provide multiple benefits for smallholder farming systems by improving their wellbeing, reducing their vulnerability to different hydroclimatic extremes while also contributing to ecosystem services provision at the landscape level. [ABSTRACT FROM AUTHOR]

The article examines the prospects of Ukraine on the world grain market and ways to increase the efficiency of maize cultivation using environmentally safe technologies in the conditions of the negative impact of climate change and other stress factors. The methodological approach takes into account the peculiarities of agrarian production based on the use of data of the Food and Agriculture Organization of the United Nations, United States Department of Agriculture, United Nations, Ministry of Agrarian Policy and Food of Ukraine and State Statistics Service of Ukraine. The dynamics of world production and export of maize grain, sown areas, production and yield of maize in Ukraine are demonstrated, which directly focuses attention on the competitiveness of Ukrainian maize on the world grain market. These arguments are confirmed by analytical results, which show that in 2022, among the world leaders of maize grain producers, Ukraine took fifth place, and among exporters - fourth. In order to mitigate the impact of climate change and other stress factors on the effective production and export of Ukrainian maize, adaptation measures are proposed, which consist in the application of modern technologies, which include: optimization of the structure of sown areas and scientifically based crop rotations with the effective use of competitive varieties and hybrids of agricultural crops, the introduction of organic and mineral fertilizers and plant protection products, the use of soil protective tillage, sideration and mulching, irrigation systems, and also the productive use of plant residues with the application of modern biodestructors. Their comprehensive implementation will contribute to the development of maize yield, grain quality, preservation of biodiversity and the solution of the grain-food problem in the world. [ABSTRACT FROM AUTHOR]

The paper selected Shijin Irrigation District as the study area. Considering the future climate change, the paper studied the effects of climate change on summer maize growth. The effects of climate change on summer maize yield were quantitatively analyzed by combining the climate scenario Representative Concentration Pathway (RCP)4.5 and AquaCrop model. The results showed that under the RCP4.5 scenario, the future yield of summer maize in Shijin Irrigation District was mainly reduced, but the yield change showed an upward trend. When the direct impact of CO2 is not considered, the yield change ranged from − 6.72~− 3.04%, and the deforestation rate of summer maize is 10.795 kg for every 1 °C increase in growth period. The increase of summer maize is 3.35 kg for every 1 mm increase in rainfall. When considering the direct impact of CO2, the yield change ranged from − 4.04~+ 0.11%. It can be seen that CO2 can compensate for the production reduction effect caused by rising temperature. [ABSTRACT FROM AUTHOR]

The geographical area between the Danube and the Black Sea, Dobrogea, represents a region with the highest aridity indices. The average precipitation in the period 1961-2016 was 464 mm. Climate changes in recent years have accentuated this phenomenon and, due to this, low production levels of 1-2 tons/ha were achieved on large areas of corn. In the year 2022/2023, over 40,000 ha cultivated with corn in Constanta county were deeply affected by the lack of rainfalls, high temperatures and long and severe drought. In these particularly dry conditions, sorghum becomes an essential alternative. This study aimed to continue the experiments with sorghum hybrids which have been carried out during the last 15 years at SPORT AGRA Ltd from Amzacea Village, Constanta County, in order to adapt the technologies to climate changes. The novelty of this research is that the adapted technologies include, among other things, the following elements: changing the planting period by approximately 25-30 days compared to the recommendations of classical technologies (planting starting from the first decade of May in order to use the moisture in the soil layer at the depth of seed incorporation 4-5 cm.), the use of early hybrids in order to overcome the periods of heat that in this area start from mid-June, the use of technological means of crop protection that include pre- and post-emergent herbicides, seed treatment prior to planting. In these conditions of development of non-irrigated sorghum technology, we propose planting this crop earlier (25-30 days compared to classic technology). In this way, the sorghum will benefit from the water reserve accumulated during the fall of the previous year. The productions of the sorghum hybrids used in the observation research fields were over 10 to/ha in most of the tested hybrids. [ABSTRACT FROM AUTHOR]

Climate changes are one of the crucial issues of modern agriculture. These changes imply the increase in average temperatures and the frequent occurrence of temperature extremes. Such conditions are stressful to maize concerning the expression of its traits. This paper presents the analysis of the maize yield concerning the yield components, morphological and chemical traits under various agroecological conditions. The objective of the study was to evaluate variability of grain yield (GY) and yield components (ear length, EL and number of kernel rows, NKR), morphological traits (plant height,PH and ear height, EH), as well as chemical traits (the whole plant dry matter, PDM and the ear dry matter, EDM), and the effect of the environment on the intensity of expression of these traits. Fifteen genotypes developed by crossing of six inbred lines were used as a material in the study carried out during the two-year period in one location. Obtained results indicate that traits were more pronounced in maize hybrids than in the parental components including the lower variability of the traits expression. NKR did not affect the yield unlike the EL, whose coefficient of determination was R² = 0.600 in both production years. The environmental effect was high for all traits except NKR. PDM and EDM were closely related to PH and EH, but they also depended on the EL and the NKR. Variations in meteorological conditions have a significant impact on the final goal of the production, the yield. Prevailing agro-ecological conditions should be a major guideline in planning the crop production and selecting the genetic material. [ABSTRACT FROM AUTHOR]

In the face of climate change scenarios, it is important to evaluate the possibility of an increase in the incidence of corn crop diseases and to promote studies aimed at creating mitigation measures. This paper aims to study the impacts that regional climate changes may have on the potential occurrence of corn common rust (Puccinia sorghi), in the region of Castro, Paraná (Brazil). The Eta climate model was driven by the global model CanESM2. We use the Historical simulation of the EtaCanESM2 model from 1981 to 2005, and future projections from 2046 to 2070 to simulate the occurrence of common rust. The criteria was adopted to simulate the common rust disease favored in environments with the minimum temperature lower than 8 °C, the maximum temperature higher than 32 °C, average temperature between 16 and 23 °C, and relative humidity higher than 95%. In Brazil, there are two different seasons for corn crop (Normaland Safrinha). Results show that relative humidity and minimum temperature simulated by the model presented good skills, approaching the observed data. Compared to the Historical simulation, the projections show a tendency to increase of maximum and minimum temperature in the future, and a tendency to decrease relative humidity. There is an increase in the number of days with the potential for the occurrence of the disease. The distribution of days with favorable conditions to rust disease tends to change in the future. In the Normaland Safrinhaseasons, there is a tendency to increase the number of days with favorable conditions to common rust occurrence. The influence of planting time is greater in Historical simulation when compared to future scenarios. The Safrinhaseason may present more days with the potential for the occurrence of common rust in the future than the Normalseason. [ABSTRACT FROM AUTHOR]

This paper presents estimates of the effects of changing climate on crop yields for grain corn and soybeans in Ontario, Canada, for 1959–2013. We were able to use a database that is more comprehensive with respect to explanatory variables than some previous efforts had available. Our model includes climate variables, prices, land quality, groundwater level, CO2 concentration, and a time trend. Our results indicate that trends in temperature and precipitation during our study period have not yet resulted in appreciable threats to crop yields in the region. [ABSTRACT FROM AUTHOR]

This paper projects the race between technologically driven increases in crop yields and changing climatic conditions in the central USA, one of the world's most productive agricultural regions. Using the highest, average, and lowest decadal rates of technologically driven increases in crop yields over the 1980 to 2017 period, we develop spatially explicit yield scenarios to the end of the twenty-first century under RCP4.5 and RCP8.5. We find that with static technological innovation, severe climate change will decrease yields by an average of 22.4% (26.1 bu. ac−1) for maize, 27.9% (8.83 bu. ac−1) for soybeans, and 20% (7.14 bu. ac−1) for winter wheat in the central USA; however, with even the lowest rates of technological yield growth, yields increase by an average of 25.0% (40.5 bu. ac−1) for maize and 30.2% (14.2 bu. ac−1) for soybeans. We conclude that technology has the potential to overcome the negative impacts of climate change on the yields of maize, soybeans, and winter wheat in the central USA, but if these increases are to be environmentally sustainable, technological developments must be information-intensive rather than input-intensive. [ABSTRACT FROM AUTHOR]

Introduction: The climate change consequences have been manifested on the environmental condition's changes (temperature, rainfall, frost, drought, and soil salinity), then, the analysis of maize genetic diversity and their environment interaction is suggested. The objectives of this research were to determine the yield potential, the response to different environments of 63 maize landrace populations representative of the genetic variation in the southeast of Coahuila, Mexico. Method: The agronomic evaluation of native maize populations of eight racial groups was carried out in the spring-summer cycle in 2013 in two contrasted and representative locations of the environmental conditions in the southeast of Coahuila. Blocks were established independently within each location, and, in one location, blocks were different planting date. The blocks × location combinations were considered different environments to explore and make an interpretation of the genotype by environment interaction. In this paper, the response to the environment is analyzed based on grain yield and days to male flowering. Results: Eight populations were identified with an outstanding average yielding potential across environments, with values between 7.4 and 8.5 t ha-1, mainly representative from the Tuxpeño, Raton and Tuxpeño Norteño races. Populations adapted to transition-high altitude areas had an average yield reduction of 4.1 t ha-1 (55.0%) after been exposed to intermediate altitude conditions. Discussion or Conclusion: The graphic interpretation of the genotype x environment interaction allowed to identify and to group the genotypes with specific adaptation in the environments of evaluation, as well as the ones with an average performance across environments. Twenty-two populations were identified with adaptation to transition- high altitude conditions, 14 to intermediate altitude areas and 27 populations with an average performance across environments. [ABSTRACT FROM AUTHOR]

Regional biogeographical models are considered to be important tools for supporting decisions relating to sustainable agricultural planning for climate change. These models are useful for a better understanding of the impact of climate change on individual crop species due to their sensitivity to regional ecological conditions. This paper deals with the application of a regional biogeographical model in order to predict the impact of climate change on growing conditions for grain maize in Central Europe. The model is based on a detailed knowledge of the relationships between the climatic characteristics of vegetation zones in landscapes with ecological growing conditions suitable for grain maize in the region under study. The results gained from using the model indicate a substantial increase in the total area suitable for growing of grain maize in the study region. By 2070, this area is expected to be triple the size it is today. Special maps are used to visualize prediction scenarios in order to support decision-making in regional planning in the study region, where grain maize is an important agricultural crop. This biogeographical model can be used in other European regions, where basic data related to vegetation zones are available. [ABSTRACT FROM AUTHOR]

The The main objective of this paper is to evaluate the impact of climate change on the soil-water regime of the Záhorská lowlands. The consequences of climate change on soil-water storage were analyzed for two crops: spring barley and maize. We analyzed the consequences of climate change on soil-water storage for two crops: spring barley and maize. The soil-water storage was simulated with the GLOBAL mathematical model. The data entered into the model as upper boundary conditions were established by the SRES A2 and SRES B1 climate scenarios and the KNMI regional climate model for the years from 2071 to 2100 (in the text called the time horizon 2085 which is in the middle this period). For the reference period the data from the years 1961-1990 was used. The results of this paper predict soil-water storage until the end of this century for the crops evaluated, as well as a comparison of the soil-water storage predictions with the course of the soil-water storage during the reference period. [ABSTRACT FROM AUTHOR]

The goal of the present paper is to present the dynamic of main foliar diseases of corn caused by the fungus Helminthosporium turcicum. The biologic material consists from an assortment of six corn hybrids. In the experimental field the technology used was the standard technology applied for this location area. The experience was implemented on the meadow soil and climatic conditions from Almajului Valley, near the town of Bozovici. Last three years bring a very significant change of the main climatic factors (temperature and rain water) with a direct influence in dynamic of majority of diseases caused by fungus and bacteria. Taking all this in consideration we try to reveal in the present paper the behavior of six from the most cultivated Dekalb corn hybrids from the western part of Romania, at the fungus Helminthosporium turcicum attack under the last three years climatic changes. The experience results were calculated after normal statistic method for experiences with three factors, where the first factor is the experimental year, the second factor was the hybrid and the third factor the nitrogen amount. The achievements bring by the present work consist from the authors experience in research of the corn diseases under climatic change and in technological conditions of intensive agriculture. Also it is interesting from the point of view of possible reactions of the pathogen relating to local biocoenosis factors. Limits of the research are that data refer strictly to the relation between hybrid, nitrogen amount and fungus Helminthosporium turcicum. Practical implications of the research are that all data presented in the present paper are a part of a complex study of corn diseases protection strategy. This strategy is important for the fungus Helminthosporium turcicum because it can be considered as endemic disease for corn in the western part of Romania. The originality of the work comes from the fact that data are relevant in view of corn hybrids behavior under specific conditions. The relevant data, experimental results give an overview of pathogen behavior in relation to experimental conditions. [ABSTRACT FROM AUTHOR]

This paper is aimed at evaluating the factors affecting the concurrent adoption of two risk coping strategies among hybrid maize farmers, namely income diversification supplemented with off-farm work and contract farming in the wake of changing climatic conditions. Climatic changes and food insecurity at the national level have emerged as key risk elements for hybrid maize production due to varying economic conditions. The present paper addresses these risks by examining various sources of risks faced by hybrid maize farmers and develops ideas to tackle these risks. Bivariate and multinomial probit models were employed to analyze numerous factors that influence farmers' choice of the simultaneous adoption of income diversification (both on and off the farm) and contract farming at the farm level. The results reveal that hybrid maize farmers' socioeconomic attributes significantly affect their adoption of risk coping tools. Similarly, the climatic, economic (price-related), biological, and financial risk perceptions and risk preference significantly influence the utilization of risk coping strategies in maize production. These outcomes extend our understanding of farmers' risk preferences and provide parameters for policymakers to forestall diverse risk sources associated with hybrid maize production. [ABSTRACT FROM AUTHOR]

Increased biofuel production has prompted concerns about the environmental tradeoffs of biofuels compared to petroleum-based fuels. Biofuel production in general, and feedstock production in particular, is under increased scrutiny. Water footprinting (measuring direct and indirect water use) has been proposed as one measure to evaluate water use in the context of concerns about depleting rural water supplies through activities such as irrigation for large-scale agriculture. Water footprinting literature has often been limited in one or more key aspects: complete assessment across multiple water stocks (e.g., vadose zone, surface, and ground water stocks), geographical resolution of data, consistent representation of many feedstocks, and flexibility to perform scenario analysis. We developed a model called BioSpatial H2O using a system dynamics modeling and database framework. BioSpatial H2O could be used to consistently evaluate the complete water footprints of multiple biomass feedstocks at high geospatial resolutions. BioSpatial H2O has the flexibility to perform simultaneous scenario analysis of current and potential future crops under alternative yield and climate conditions. In this proof-of-concept paper, we modeled corn grain (Zea mays L.) and soybeans (Glycine max) under current conditions as illustrative results. BioSpatial H2O links to a unique database that houses annual spatially explicit climate, soil, and plant physiological data. Parameters from the database are used as inputs to our system dynamics model for estimating annual crop water requirements using daily time steps. Based on our review of the literature, estimated green water footprints are comparable to other modeled results, suggesting that BioSpatial H2O is computationally sound for future scenario analysis. Our modeling framework builds on previous water use analyses to provide a platform for scenario-based assessment. BioSpatial H2O's system dynamics is a flexible and user-friendly interface for on-demand, spatially explicit, water use scenario analysis for many US agricultural crops. Built-in controls permit users to quickly make modifications to the model assumptions, such as those affecting yield, and to see the implications of those results in real time. BioSpatial H2O's dynamic capabilities and adjustable climate data allow for analyses of water use and management scenarios to inform current and potential future bioenergy policies. The model could also be adapted for scenario analysis of alternative climatic conditions and comparison of multiple crops. The results of such an analysis would help identify risks associated with water use competition among feedstocks in certain regions. Results could also inform research and development efforts that seek to reduce water-related risks of biofuel pathways. [ABSTRACT FROM AUTHOR]

Global surface temperature is projected to warm over the coming decades, with regional differences expected in temperature change, rainfall and the frequency of extreme events. Temperature is a major determinant of crop growth and development, affecting planting date, growing season length and yield. We investigated the effects of increments of mean global temperature warming from 0.5 °C to 4 °C on soybean and maize development and yield, both globally and for the main producing countries, and simulated adaptation through changing planting date and variety. Increasing temperature resulted in reduced growing season lengths and ultimately reduced yields for both crops. The global yield for maize decreased as temperature increased, although the severity of the decrease was dependent on geographic region. Small temperature increases of 0.5 °C had no effect on soybean yield, although yield decreased as temperature increased. These negative effects, however, were partly compensated for by the implementation of adaptation strategies including planting earlier in the season and changing variety. The degree of compensation was dependent on geographical area and crop, with maize adaptation delaying the negative effects of temperature on yield, compared to soybean adaptation which increased yield in China, India and Korea DPR as well as delaying the effects in the remaining countries. The results of this paper indicate the degree to which farmer-controlled adaptation strategies can alleviate the negative impacts of increasing temperature on two major crop species. [ABSTRACT FROM AUTHOR]

To learn the effects of climate change on cultivation patterns of spring maize and its suitability will benefit the strategic decisions for future agricultural adaptation. In this paper, based on the daily data from 68 meteorological stations and 82 agro-meteorological observation stations in Northeast China between 1961 and 2010, the cultivation pattern of spring maize and its climatic suitability in Northeast China were investigated. The agricultural climatic suitability theory was applied. The specific growth phases of spring maize that were most sensitive to environmental limitations were further divided into four stages: from germination to emergence, from emergence to jointing, from jointing to tasseling, and from tasseling to maturity. The average resource suitability index ( I sr ) was established to evaluate the effects. Higher values of I sr indicate a higher degree of climatic resource suitability. Over the past five decades, the northern planting boundaries of different maturities (late, medium-late, medium, medium-early and early) of spring maize varieties in Northeast China all markedly extended northward and eastward. Of all the varieties, the medium-late maturity variety had the most expanded planting area. This further illustrated the importance of promoting medium-late range heat-tolerant cultivars of spring maize in reducing the unfavorable effect of climate change in the near future in Northeast China. In addition, the most significant extension was found in the early 21st century. Moreover, the southern planting boundaries of unsuitable planting spring maize areas continually compressed northward from the Tonghe County of Heilongjiang Province (128°49′, 46°21′) to the Huma County of Heilongjiang Province (124°11′, 51°26′). Climate change affected not only the planting patterns of spring maize, but also the climatic suitability of spring maize. Significant temporal and spatial changes of I sr from 1961 to 2010 were found. The I sr showed increasing trends, which increased by 0.19 in Heilongjiang Province, 0.16 in Jilin Province and 0.12 in Liaoning Province. Spatial differences of I sr were obvious, with high values shifting northeastward over the past 50 years, indicating more efficient suitability of agricultural climatic resources in Northeast China. [ABSTRACT FROM AUTHOR]

This paper analyzes the meteorological drought events in Paraguay in the period of 1964 to 2011, using the Standardized Precipitation Index (SPI). The objective is to determine if the frequency and/or severity of droughts has increased or decreased in the last years, in response of climate change. They The southernmost parts of the country are affected by severe droughts producing damage to soybean and corn crop during the rainy season (October-March) especially during the summer of 2008-2009. The years of 1967, 1968, 1978, 1979, 2000 and 2008 was identified as severe to extreme drought events and coincides with La Niña event. However, the relationship between all drought events, especially those agricultural droughts and La Niña is not clear, suggesting the necessity of new research, focusing on new drivers to explain the cause of the droughts. The economy of Paraguay, based for good part on agriculture, is clearly vulnerable to droughts. Even though no undeniable increasing trend in drought frequency/severity was detected, contingency plans to diminish drought impacts ought to be elaborated. [ABSTRACT FROM AUTHOR]

Climate change is anticipated to affect European agriculture, including the risk of emerging or re-emerging feed and food hazards. Indirectly, climate change may influence such hazards (e.g. the occurrence of mycotoxins) due to geographic shifts in the distribution of major cereal cropping systems and the consequences this may have for crop rotations. This paper analyses the impact of climate on cropping shares of maize, oat and wheat on a 50-km square grid across Europe (45–65°N) and provides model-based estimates of the changes in cropping shares in response to changes in temperature and precipitation as projected for the time period around 2040 by two regional climate models (RCM) with a moderate and a strong climate change signal, respectively. The projected cropping shares are based on the output from the two RCMs and on algorithms derived for the relation between meteorological data and observed cropping shares of maize, oat and wheat. The observed cropping shares show a south-to-north gradient, where maize had its maximum at 45–55°N, oat had its maximum at 55–65°N, and wheat was more evenly distributed along the latitudes in Europe. Under the projected climate changes, there was a general increase in maize cropping shares, whereas for oat no areas showed distinct increases. For wheat, the projected changes indicated a tendency towards higher cropping shares in the northern parts and lower cropping shares in the southern parts of the study area. The present modelling approach represents a simplification of factors determining the distribution of cereal crops, and also some uncertainties in the data basis were apparent. A promising way of future model improvement could be through a systematic analysis and inclusion of other variables, such as key soil properties and socio-economic conditions, influencing the comparative advantages of specific crops. [ABSTRACT FROM PUBLISHER]

In the North China Plain, the grain yield of irrigated wheat-maize cropping system has been steadily increasing in the past decades under a significant warming climate. This paper combined regional and field data with modeling to analyze the changes in the climate in the last 40 years, and to investigate the influence of changes in crop varieties and management options to crop yield. In particular, we examined the impact of a planned adaptation strategy to climate change -'Double-Delay' technology, i.e., delay both the sowing time of wheat and the harvesting time of maize, on both wheat and maize yield. The results show that improved crop varieties and management options not only compensated some negative impact of reduced crop growth period on crop yield due to the increase in temperature, they have contributed significantly to crop yield increase. The increase in temperature before over-wintering stage enabled late sowing of winter wheat and late harvesting of maize, leading to overall 4-6% increase in total grain yield of the wheat-maize system. Increased use of farming machines and minimum tillage technology also shortened the time for field preparation from harvest time of summer maize to sowing time of winter wheat, which facilitated the later harvest of summer maize. [ABSTRACT FROM AUTHOR]

Abstract: Groundwater irrigation consumes considerable energy as well as water resources across the globe. Using a case study from Iran, this paper explores how enhanced farm water management can help in reducing groundwater exploitation and subsequently limiting energy consumption and the carbon footprint of the groundwater economy. Groundwater use for irrigated agriculture in Iran has increased vastly over the last three decades. We estimate that groundwater pumping consumes 20.5billionkWh electricity and 2 billion liters of diesel and contributes to 3.6% of the total carbon emission of the country. Thus there is an opportunity to reduce energy use and carbon emissions by pumping less water. However, groundwater use remains important for food security. To identify opportunities for water conservation within agricultural fields, the SWAP model was applied to simulate crop growth and field water balance for three major irrigated crops, i.e. wheat, maize, and sugar beet in the Gamasiab River Basin, one of the highest groundwater using irrigated areas of Iran. The model simulations showed that by adopting improved irrigation schedules and improving farm application efficiencies, water productivity will increase, and irrigation water withdrawals from groundwater can be reduced significantly with no reduction in yields. While these improvements may or may not result in water saving and retarding the ground water decline, depending on the fate of excess application, they will have significant water quality, energy, and carbon implications. Such reduction in irrigation application can result in 40% decline in energy consumption and subsequently carbon emission of groundwater use. [Copyright &y& Elsevier]

The North China Plain (NCP) is the most important agricultural production area in China. Crop production in the NCP is sensitive to changes in both climate and management practices. While previous studies showed a negative impact of climatic change on crop yield since 1980s, the confounding effects of climatic and agronomic factors have not been separately investigated. This paper used 25 years of crop data from three locations (Nanyang, Zhengzhou and Luancheng) across the NCP, together with daily weather data and crop modeling, to analyse the contribution of changes in climatic and agronomic factors to changes in grain yields of wheat and maize. The results showed that the changes in climate were not uniform across the NCP and during different crop growth stages. Warming mainly occurred during the vegetative (preflowering) growth stage of wheat and maize, while there was a cooling trend or no significant change in temperatures during the postflowering stage of wheat (spring) or maize (autumn). If varietal effects were excluded, warming during vegetative stages would lead to a reduction in the length of the growing period for both crops, generally leading to a negative impact on crop production. However, autonomous adoption of new crop varieties in the NCP was able to compensate the negative impact of climatic change. For both wheat and maize, the varietal changes helped stabilize the length of preflowering period against the shortening effect of warming and, together with the slightly reduced temperature in the postflowering period, extend the length of the grain-filling period. The combined effect led to increased wheat yield at Zhengzhou and Luancheng; increased maize yield at Nanyang and Luancheng; stabilized wheat yield at Nanyang, and a slight reduction in maize yield at Zhengzhou, compared with the yield change caused entirely by climatic change. [ABSTRACT FROM AUTHOR]

Abstract: Soil carbon sequestration has been recognized as an effective, low-cost technology to mitigate climate change. Simulation models, alone or in combination with soil sampling and other techniques, can help monitor changes in soil carbon levels as affected by climate, soil, and management conditions. The objective of this paper is to test the ability of the Environmental Policy Integrated Climate (EPIC) model to simulate total organic carbon (TOC) dynamics in soils of the central region of the Province of Córdoba (Argentina) and evaluate, through modeling, the capacity of Córdoba''s agricultural soils to act as sources or sinks of atmospheric CO2. We tested EPIC against measurements made in a spatially distributed 40-year chronosequence of a temperate shrubland forest transitioning to agricultural use with conventional practices and in two long-term tillage (moldboard plow, chisel plow, and no till) and crop rotation (maize [Zea mays L.]–soybean [Glycine max L. Merr.]) field studies. Overall, the EPIC model demonstrated a good capability for simulating TOC dynamics. In the chronosequence, the TOC lost during 40 years of cultivation after deforestation was calculated at 38.4Mgha−1 while that simulated by the model was 44.1Mgha−1. These values represented losses of 44% and 45% of the original TOC content, respectively. In the two long-term field experiments, the TOC simulated over the entire depth was close to the observed values and reflected the trends of the various treatments. For the most common conditions of croplands in Córdoba, crops grown in rotation with conservation tillage, particularly no till, would make soils act as sinks of atmospheric CO2. [Copyright &y& Elsevier]

A national assessment (NA) evaluated the potential consequences of climate change and variability on the agriculture, water resources, as well as other economic and natural resource sectors in the United States. As part of this process, we used scenarios of the HadCM2 GCM and the EPIC agroecosystem model to evaluate climate-change impacts on crop yields and ecosystem processes. Baseline climate data were obtained from national records for 1961–1990. The scenario runs for 2025–2034 and 2090–2099 were extracted from a HadCM2 run. EPIC was run on 204 representative farms under current climate and two 10-year periods centered on 2030 and 2095, each at CO2 concentrations of 365 and 560 ppm. Crops were simulated under both dryland and irrigated management, with irrigation water supply estimates taken from the HUMUS simulations in Paper 1. Texas, New Mexico, Colorado, Utah, Arizona, and California are projected to experience significant temperature increases by 2030. Slight cooling is expected by 2030 in Alabama, Florida, Maine, Montana, Idaho, and Utah. Larger areas are projected to experience increased warming by 2095. Uniform precipitation increases are expected by 2030 in the northeast. These increases are predicted to expand to the eastern half of the country by 2095. Regionally, dryland corn yields could increase, decrease or remain unchanged under the two scenarios. EPIC simulated yield increases for the Great Lakes, Corn Belt and Northeast regions. Simulated yields of irrigated corn were predicted to increase in almost all regions. Soybean yields could decrease in the Northern and Southern Plains, the Corn Belt, Delta, Appalachian, and Southeast regions and increase in the Lakes and Northeast regions. Simulated wheat yields exhibited upward trends under scenarios of climate-change. Evapotranspiration in dryland corn is expected to increase in both future periods while water-use efficiency will decrease. National corn production in 2030 and 2095 could be affected by changes in three major producing regions. In 2030, corn production could increase in the Corn Belt and Lakes regions but decrease in the Northern Plains leading to an overall decrease in national production. National wheat production is expected to increase during both future periods. A proxy indicator was developed to provide a sense of where in the country, and when water would be available to satisfy change in irrigation demand for corn and alfalfa production as these are influenced by the HadCM2 scenarios and CO2-fertilization. Irrigation requirement by irrigated crops declines under these scenarios as transpiration is suppressed. [Copyright &y& Elsevier]

One of the consequences of climate change in Sub-Saharan Africa is that farmers would be more exposed to production risk. Therefore, it is imperative to analyse the climate-related risk and maize production in Southwest, Nigeria. Secondary data between 1981 and 2012 were collected on relevant variables and analysed using Growth Function, Co-integration Model (Autoregressive Distributed Lag Approach) and J-P Model. The results confirmed the presence of long-run equilibrium between maize production and temperature, rainfall and relative humidity. The Error Correction Model (ECM) value was -0.0238 for the enterprise. The results of the analysis on the climaterelated risk indicated that temperature increased the production risk of maize farmers. It can be concluded that farmers face climate-related risk as temperature increased the production risk of maize farmers. Therefore, stakeholders should create more awareness on the need to always practice eco-friendly activities and put in place coping strategies against the menace of climate change. [ABSTRACT FROM AUTHOR]

In the context of global climate change, droughts pose a serious threat to agricultural development and food security. Assessing the vulnerability and risk of regions to drought is important for its prevention. In this paper, to understand the vulnerability of maize to drought in different regions of China and quantify its risk, 241 prefecture-level administrative regions (including prefecture-level cities, autonomous prefectures, prefectures, and leagues) in the five main maize-growing regions of China are used as study area. By using a method of global sensitivity analysis, the extended Fourier amplitude sensitivity test (EFAST), we chose two parameters that are most sensitive to maize yield to calibrate the AquaCrop model. We then used it to simulate the water stress of maize in the study area under different irrigation scenarios as well as the corresponding production. We defined the drought hazard index (DHI) as the daily average of the crop water stress indicator during the growing season, and used it to describe the intensity of droughts. Vulnerability curves (the function of the DHI and rate of yield loss) of the entire growth season and various stages of growth were also formulated. These were used to determine the loss of maize yield under four levels of risk (return periods of 5, 10, 20, and 50 years). The results showed the following: 1) the vulnerability curve of maize for the entire growing season was consistent with logistic function, and the coefficient of determination of the equation of regression was R 2 = 0.93. The rate of yield loss began increasing rapidly once the DHI had reached 0.2 and approached its maximum value when the DHI was 0.6. 2) The coefficients of determination of the results of regression in 14 scenarios, in which drought had occurred in different stages of growth, were between 0.28 and 0.92. Drought from the tasseling stage to the milk stage had the most significant negative effect on the maize yield, followed by the seventh leaf stage to the tasseling stage and the sowing stage to the seventh leaf stage. Drought from the milk stage to physiological maturity had the least negative effect on the maize yield. 3) Under all four risk levels, the DHI and the yield loss rate of maize in China decreased from the northwest to the southeast. The Northwest Irrigated Maize Region had the highest drought risk among the five maize-growing regions, followed by the North Spring Maize Region, the Huang-Huai-Hai Summer Maize Region, the South Hilly Maize Region, and the Southwest Mountain Maize Region. 4) The DHI calculated by the average method was more representative than that calculated using the accumulative method. Unlabelled Image • A new drought hazard index was proposed for building drought loss curves. • Drought vulnerability curves were built for five main maize-growing regions in China. • Yield loss curves of maize were built for droughts occurred in various growth stages. • Risk of maize yield loss for return periods of 5, 10, 20, and 50 years were assessed. • The drought risk of maize in China decreases from northwest to southeast. [ABSTRACT FROM AUTHOR]

The impact of climate change on agricultural systems has become a reality that currently threatens food security in numerous regions worldwide. However, concrete consequences of climate change on agricultural yields still remain unknown in many countries around the world, including Romania. This study conducts a first-ever analysis of the impact of climate change on maize productivity in Romania, the European Union's leader in maize harvested production, which holds almost 30% of the European maize production. The paper explores complex statistical relationships between the climatic water balance (CWB)/its constituting parameters precipitation (P) and reference evapotranspiration (ETo) and maize yields (Zea mays L.) recorded nationally from 1990 to 2013, a key-period in Romania in terms of climate and socio-political changes. The analysis of various agro-climatic data, based on well-established methods (linear regression and bootstrapping), showed that the countrywide dependence of maize yields variability to changes in the analyzed climatic variables was considerable and reached peak values of roughly 60% for the CWB-yield relationship and around 50% for the P-yield and ETo-yield relationships. At the same time, a significant sensitivity of maize yield dynamics was found in response to a 1-unit climate change, which, on average, was quantified at 5 kg/ha/yr for a 1-mm variation of the CWB, and at 19 kg/ha/yr and 11 kg/ha/yr for a 1-mm change in P and ETo, respectively. In addition to this agricultural impact, our findings regarding the economic impact associated to concrete climatic trends (CWB decreases and ETo increases over the 24 years, consistent with an overall increase of the humidity deficit, and P increases, consistent with humidity surplus) indicate total costs of approximately 53 mil € (or almost 1% of the national agricultural gross domestic product) for the CWB-yield relationship, and of ~200 mil € (~3%) for ETo-yield. It was found that the separate influence of P in maize dynamics was positive, with net financial gains of up to ~130 mil € (~2%). However, our findings show that only the economic costs associated with the impact of ETo on maize productivity are highly statistically reliable. Our results issue a warning about the urgent measures to fight climate change effects on agriculture in Romania, which are necessary especially in the counties located in the Extra-Carpathian regions, highly vulnerable to climate dynamics. • Investigation of climate change impact on agricultural yields in Romania after 1990. • Analysis between climatic water balance (CWB)/precipitation (P)/reference evapotranspiration (ETo) and maize yields. • Up to ~60% dependence of maize yields variability to climatic changes, for the CWB – maize yields relationship. • Average sensitivity of 5 kg/ha/yr, 19 kg/ha/yr and 11 kg/ha/yr, for a 1-mm variation of the CWB, P and ETo. • Total economic costs of up to 53 mil €/200 mil €, associated with the negative impact of CWB/ETo on maize yields. [ABSTRACT FROM AUTHOR]

Examining the effects of climate change on spring maize, and its suitability under dynamic cultivation patterns, will aid strategic decision-making for future agricultural adaptation. This paper investigates the climate suitability of spring maize, based on daily data from 50 meteorological stations, and statistics on maize yield and area at the county level in Jilin Province, China, between 1986 and 2015. Based on a significant correlation between the cultivation patterns indicator ≥10 °C accumulated temperature (AAT10) and the average yield (R2 = 0.503), the yield data are used to determine suitable thresholds for meteorological factors under the dynamic cultivation pattern, and a fuzzy fitness approach is used to evaluate the climate suitability. The results showed a good agreement between suitability estimates and scaled observed yields (average d = 0.705). Moreover, good consistency between cultivation patterns, climate suitability and yield show that the late-maturing varieties of maize have gradually moved northward and eastward, and the areas of high suitability and high yield have gradually expanded eastward. In addition, drought and chilling hazard factors limit the suitability of climate resources, especially in the eastern and western regions. [ABSTRACT FROM AUTHOR]