АГРОКЛИМАТИЧЕСКИЕ РАЙОНЫ И УРОЖАЙНОСТЬ СЕЛЬСКОХОЗЯЙСТВЕННЫХ КУЛЬТУР В ИЗМЕНЯЮЩИХСЯ УСЛОВИЯХ РЕГИОНАЛЬНОГО КЛИМАТА

Climate change is a complex and contentious public issue, but the risk-management options available to us are straightforward and have well-characterized strengths and weaknesses.

Climate Change, Sea Level Rise, and Adaptation: A Case Study of Bangladesh

Impact of climate change on sugarcane (Saccharum spp. interspecific hybrids) crop growth, development and productivity remains unclear globally. In China, the per capita available water resource amounts to only 1/4th of the global average. The limited water is one of the most significant constraints for sustainable agriculture development and crop productivity in China, and thus water-saving irrigation technology can reduce the seasonal water shortage in agricultural crop production, improve crop yield and quality, and enhance sustainable agricultural crop development. Keeping this in view, we conducted a field experiment at Guangxi sugarcane-growing hilly dry land with steep slope from 2017 to 2020 in plant and two ratoon crops. Results showed that bud germination (%), tillering rate, plant height and millable cane were not significantly different in spray and drip irrigation treatments. As compared to control, spray irrigation and drip irrigation (DI) remarkably increased the crop growth and yield. Drip irrigation produced a significantly higher cane production, consumed less irrigation water (65%) and provided maximum irrigation water use efficiency. Our study suggested that DI was far more effective in conserving water for irrigation and could be recommended and adopted in Guangxi and similar crop production regions.

The results of many scientific studies prove the impact of climate change on agriculture. However, there is no definitive conclusion about what the future holds for agriculture. The consequences of such changes will most likely be manifested at the regional level, which will require adaptation of agriculture in the relevant territory. The purpose of the study is to assess changes in agroclimatic indicators and analyze their impact on the yield of agricultural crops. The work was carried out by statistical processing of agroclimatic data of ten meteorological stations of Ukraine for the years 2018–2023. and indicators of productivity and gross harvest of agricultural crops for 1923–2023. For a more accurate interpretation of the results, we used a paired regression analysis using the Pearson coefficient and Fisher's F test. The greatest positive effects of climate change in the form of an increase in the duration of the growing season and, accordingly, an increase in the potential productivity of agricultural crops can be expected for the northern territories. These regions themselves were in the war zone, and over the sixty-year period, the tendency to increase climatic parameters related to agriculture was noted. The most significant changes were also noted in the agro-climatic region, the territory of which is mainly located in the Carpathian mountain massif. At the same time, the yield of open ground vegetables increased from 3.6 to 31.4 t/ha, there are positive trends in harvesting potato tubers per unit area. Standardization of drought screening has been shown to increase yield stress heritability to values similar to those obtained for yield under well-wet conditions. Currently, it has been proven that drought-resistant varieties can be bred by direct selection for yield under stressful conditions. Currently, many quantitative trait loci (QTL) for drought tolerance have been identified in rice, but only a few of them are suitable for use in marker breeding. However, the identified genes of high drought tolerance can be effectively used in drought tolerance breeding. The use of molecular markers will increase the effectiveness of selection work.

Agricultural cropping pattern and crop production in the Southwestern coastal region of Bangladesh is affected severely by climate-induced events and climatic variability. This study shows the impacts of climatic-induced events (e.g., cyclone Sidr and Aila) on agricultural cropping patterns and crop production in two disaster-prone Southwestern coastal districts (i.e., Khulna and Satkhira) in Bangladesh. For analyzing the trend of climatic variability (e.g., temperature, rainfall, and relative humidity), 35 years (1980–2014) of climatic data were used. This study shows that the agricultural crop production in the selected Southern coastal region of the country had declined significantly when the two major cyclones (i.e., Sidr and Aila) approached in 2007 and 2009, respectively. A correlation analysis has been performed between annual average crop production and annual average climatic data to identify the influence of climatic variability on crop production.

Climate change poses serious threats to agriculture and food security, and extreme weather events have reduced crop productivity worldwide. Future projections predict that the average global temperature will rise by 2.0 to 6.4 °C and the increase in sea level will be 59 cm by the end of 21st century. The unprecedented rise in temperature has led to an increase in the incidence of heat waves, droughts, floods, and irregular patterns of precipitation. These changes have a dramatic impact on prevailing agricultural cropping systems, productivity, and food security of people regionally and globally. The change in climatic parameters have substantial effects on weeds, diseases, insect, and pests in different ways, and can result in an increase of their geographical distribution, number of generations, and survival during winter. Thus, to sustain the crop production on the eve of climate change is the main challenge. Therefore, adaptation measures are prerequisites to reduce the effects of climatic changes on production of agricultural crops. In this review, a brief insight has been given in the impact of climate change on agriculture and, the future challenges of climate change on the production of crops. In addition, integrated approaches, or recent developments for the improvement of crops such as breeding, transgenic approaches to biotechnology, and functional genomics, agronomic practices, cultivation of climate resilient crops, and nanotechnology for abiotic stress such as drought stress, temperature, heat, and salinity tolerance have also been discussed.

The process of climate warming significantly affects agroclimatic resources and agricultural production. We study the agroclimatic resources and their variability on the territory of the Republic of Bashkortostan (Russia). The Bashkortostan has a high agricultural potential and holds a leading position in the country in the production of grain crops, potatoes, milk, and honey. Currently, no detailed studies have been conducted for this area to assess the effects of global climate change on agro-climatic resources. World experience shows such research becomes strategically important for regions with powerful agricultural production. We used the sums of average daily air temperatures above 0 and 10 °C, the G.T. Selyaninov hydrothermal coefficient, and the Ped aridity (humidification) index as agroclimatic indicators. We used data of long-term meteorological observations of 30 meteorological stations for the period of 1961–2020. We revealed the long-term dynamics of the agroclimatic indicators and the spatial and temporal regularities in their distribution on the territory of Bashkortostan. There is a steady increase in the sums of average daily air temperatures above 0 and 10 °C. Against this background, aridity increases, which is especially manifested in the southern parts of the Republic of Bashkortostan. We assessed the impact of agroclimatic indicators on the main types of agricultural crops in the republic. We revealed that the greatest positive impact on the yield of oilseeds, cereals, and industrial crops is made by precipitation at the beginning (r = 0.50, r = 0.44, and r = 0.52, respectively) and in the middle of the growing season (r = 0.55, r = 0.76, and r = 0.51, respectively). Temperature and precipitation during the growing season have a complex effect on cereals. This is proven by correlations with HCS and the Ped index (r = 0.45 and r = −0.56, respectively). Aridity at the beginning of the growing season affects the yield of oilseeds and potatoes. This is confirmed by correlations with the Ped index (r = −0.49 and r = −0.52, respectively). In general, the aridity of the growing season has a significant impact on the yield of cereals (r = −0.57). Negative relationships have been found between the air temperature growing season and the yield of potatoes (r = −0.50) and cereals (r = −0.53). The results of the study were compared with data from the Copernicus Climate Change Service database. We identified climate trends under RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5 scenarios. These scenarios should be taken into account when developing plans for the adaptation of agriculture in the Republic of Bashkortostan to changes in the regional climate. Maximum decrease in precipitation is established for the RCP 6.0 scenario. This can have an extremely negative impact on crop yields. This problem is especially relevant for the southern part of the Republic of Bashkortostan. The information presented in the study will allow for a more effective adaptation of the agricultural sector to current and future climate changes.

International audience

The burning of fossil fuels in developed nations and the conversion of natural grasslands and forests to intensely managed agricultural production systems are the single most important anthropogenic sources of greenhouse gases (GHGs) contributing to global warming. Such activities do not only contribute to the accumulation of GHGs in the atmosphere, but also lead to the depletion of the global soil organic matter (SOM) pool, further impacting soil fertility and crop productivity. Climate change will likely affect the distribution and productivity of life-sustaining agricultural crops and livestock in different regions of the world, including temperate and tropical biomes. As a result, the United Nations Development Program suggested that millions of people may be facing shortages of food and continued degradation of their agricultural resources. Therefore, one of the challenges is to maintain agricultural productivity to meet current and projected trends in food production, while at the same time minimizing GHG emissions, increasing C (C) sequestration and maintaining soil fertility. This, coupled with large-scale land, soil, and water degradation, will challenge the long-term and sustainable production of agricultural resources that promote food security. Traditional coping mechanisms, such as conventional agroecosystem management practices may not be an economically feasible adaptation strategy, especially for those already experiencing socioeconomic adversity. Therefore, improvement and refinement of ecologically-based land management practices are essential. Soft-path agricultural technologies such as the complex agroecosystems, including agroforestry systems, may make a substantial contribution in the mitigation of GHGs, the sequestration of C, and other ecological services while maintaining a long-term sustainable production of agricultural products. Due to their multipart structure, complex agroecosystems are likely more resilient to climate change and provide a sustainable alternative to conventional land management practices. This special issue of the Agriculture Journal , on the role of complex agroecosystems in climate change mitigation, encapsulates research from temperate and tropical biomes, with a special focus on agroforestry systems. In tropical regions, Chesney et al. investigated the performance of cowpea ( Vigna unguiculata L.) on alley cropping agroforestry systems with Gliricidia sepium (Jacq.) Kunth ex Walp. and Leucaena leucacephala (Lam.) de Wit and a no-tree control on an infertile acidic soil in Guyana. Their goal was to evaluate the ability of fast-growing nitrogen (N 2 )-fixing trees ( G. sepium , L. leucocephala ) on cowpea yield. Such practice would maximize the cowpea crop yield but minimize the need for an external source of N fertilizers. They suggested that such practices provide a sustainable source of food, and conserve soil resources but it will also reduce the potential production of the GHGs over the long-term. They noted that these agroforestry practices would curb N 2 O emissions, which has a global warming potential 296 times greater than that of CO 2 . Smith and Oelbermann used a qualitative approach to evaluate the perception and knowledge of climate change by landowners in a remote Costa Rican agricultural community. They also evaluated the type of sustainable agricultural practices already implemented that could also serve as a strategy to climate change adaptation. Their study showed that community members were aware of climate change and already observed changes in local weather patterns over the past decade that affected the distribution of vegetation and wildlife. As a result, agricultural producers were continually striving to implement agroforestry practices which were viewed as more robust and resilient to climate change by helping to maintain agricultural productivity while also providing economic and socioecological needs. In temperate regions, Evers et al. provided an overview of the potential of tree-based intercropping (agroforestry alley cropping) systems in climate mitigation through the reduction of GHG emissions. They outlined the most recent research results from southern Ontario and Quebec and found that agroforestry systems could lower N2O emissions by 1.2 kg ha -1 y -1 compared to a conventional (monoculture) agroecosystem. They also suggested that the potential of agroforestry systems to sequester C in the soil and tree component was greater than in conventional agroecosystems, especially if fast-growing tree species for bioenergy production were used. Such practices may also provide an opportunity to receive payment for the ecological services provided by the agroforest, making these production systems a better option than conventional systems for agricultural producers in temperate regions. Isaac et al. investigated the internal accumulation and retention of nutrients in nutrient-spiked pine seedlings commonly used in temperate agroforestry systems and hypothesized that nutrient-spiking would lower seedling transplanting stress and reduce pressure on native soil resources and proposed that nutrient spiking would also lead to an increase in nutrient availability for the growing crop and also minimize competition between trees and crops. They found a favorable response in tree and crop root biomass accumulation in nutrient-spiked treatments and found that N, phosphorus (P) and potassium (K) significantly increased in the pine tissue and resulted in a steady or increased uptake of these nutrients by the crop (maize). Isaac et al. suggested that such specialized practices may be required when establishing agroforestry systems for the benefit of nutrient regulation and enhanced capacity to sequester C for the long-term mitigation of climate change. The Argentine Pampa is one of the most fertile regions in the world and natural grasslands and forests continue to be converted to intense agricultural production systems. Such practices have led to large losses in soil organic carbon (SOC) and contributed to the accumulation of GHGs in the atmosphere. The paper by Posse et al. outlines the absence of precise quantitative data on the emission and sequestration of GHG, which impedes a better understanding of the mechanisms driving CO2 emissions from agroecosystems. Although the paper by Posse et al. does not investigate CO2 fluxes from complex agroecosystems, but instead it provides vital information on the emission of this GHG in one of the most rapidly expanding agricultural frontiers in the world, which is also experiencing the effects of global warming on crop productivity. Posse et al. aim to characterize the exchange of CO 2 , using eddy covariance techniques, in a monoculture soybean system during an extreme dry summer which resulted in a high crop loss. They found that the greatest emission of CO2 occurred during premature crop senescence (due to drought) but the field became a CO 2 sink once the soil as covered by weeds. As such, changes in crop phenology and botanical composition (weeds) coincided with changes in the flux of CO 2 . The papers presented in this special issue of the Agriculture Journal provided an important insight into the potential of decreasing GHGs and maximizing C sequestration. These papers have also provided an important stepping stone by outlining the future direction of research to further understand the importance and role of complex agroecosystems in mitigating climate change. This research field is in its infancy but results are favorable by indicating that complex agroecosystems not only enhance the cycling of nutrients and the productivity of agricultural crops and show greater resilience to climate change, but they can also play an important role in the mitigation of climate change.

Climate Change and Health: Strengthening the Evidence Base for Policy

The productivity of agricultural crops depends on an optimal degree of genetic factors, climate, soil and level of agrotechnology. Climate changes have a significant negative impact on the productivity of agricultural crops. The study is focused on a multi-year analysis of the main climate indicators, such as temperature and precipitation. The data collected from hydrometeorological stations in the Korça region of Albania were processed and compared with the corresponding data from two previous 30-year periods. The increase in temperature indicated a trend without significant volatility from one year to the next, and the annual amount of precipitation did not fundamentally change; however, a greater concern was the amount of rain that fell over fewer days but in larger amounts. Moreover, the structure of the diagram which integrated temperature and average monthly rainfall showed that there had been an increase in the periods of drought. The changes in agro-climatic indicators present a challenge for producers in the field of agriculture if they are to meaningfully remodel agricultural areas and determine the most appropriate cultivation technologies for agricultural crops.

Study of Socio-economic Factors Influencing on Adaptation of Smallholder Farmers to Climate Change in Mountainous Areas (Case study: Malavi Dehestan of Poldokhtar County)

Agriculture is one sector of the economy which is highly vulnerable to climate change because of the natural relationship between environment, particularly temperature and water availability, and agricultural productivity. Changing climate is increasingly affecting high-value perennial plantation crops such as tea, rubber, coconut, palm oil, and coffee which generate significant export revenues and provide a major source of employment for rural populations in developing countries. Many studies in the literature have focused on climate change impacts on major annual crops; however, to date, there have been very few assessments of the economic impacts of climate change on perennial plantation agriculture. This thesis therefore seeks to estimate the impacts of climate change on two important aspects of plantation agriculture - crop production and labour demand - for the case of the tea plantation sector in Sri Lanka, as an example of a high-value perennial plantation crop in a developing country. The thesis also aims to identify enablers and barriers of adaptation to climate change for this sector of Sri Lanka’s economy. The impacts of climate change on production in Sri Lanka’s tea plantations are studied at estate-level (the primary decision making production unit) across all of the country’s tea growing regions using monthly resolution primary data for the period 2000-2014. The study employs a novel two-stage panel data approach to analyse weather and climate change effects on tea production and then to estimate production impacts for the short-, medium- and long-term future under three different global emissions scenarios. These analyses indicate that a hotter and wetter climate will have a detrimental effect on production. In high, medium and low emissions futures, the predictions show a negative proportional impact on production from increased rainfall and increased average temperature. On average across the data sample, a 12% decline in annual tea production is predicted under a high emissions scenario by 2050. The impacts of climate change on labour demand in tea plantations in Sri Lanka are investigated by implementing a panel structural model of profit maximisation based on a normalised quadratic functional form. The analysis uses historical primary data on estate profits, input prices and output prices, together with monsoonal rainfall, temperature and wet days for years between 2002-2014 to quantify climate impacts on estates’ demand for labour. Anticipated changes in rainfall are predicted to reduce annual labour demand by 2.6% across the tea plantation sector. This could have considerable social and welfare implications, particularly for the Indian Tamil women who comprise the majority of the sector’s workforce. Plantation agriculture is likely to be highly vulnerable to climate change because of its reliance on rain-fed production, long economic life span and the inability to easily switch crops due to high upfront capital costs. These distinct differences between annual and perennial agriculture, and the important role which plantation cropping plays in developing world agriculture, suggest that it is important to identify factors which affect choice of climate adaptation options in perennial crop production. Comprehensive knowledge of available adaptation options is of utmost importance if Sri Lanka’s tea estate managers are to counteract production losses from climate change and maintain their competitiveness in the international market. This is also vital for efficient and effective channeling of society’s resources to address the consequences of climate change. Employing data derived from face-to-face interviews with 50 tea estate managers in Sri Lanka, this study examines factors affecting choice of preferred adaptation options, barriers to adaptation and associated policy implications for tea production in Sri Lanka, as an example of a perennial tree crop system in a developing country. Tea estate managers are already adapting to a changing climate; however, particular adaptation methods are only adopted in some situations and locations. Multinomial logit analysis of data from estate manager interviews indicates that availability of information on climate change, company size, tea growing elevation, and observed increases in temperature and rainfall are key factors influencing the choice of preferred adaptation option. Analysis also finds that barriers such as a lack capital, inadequate access to near-term and medium-term climate knowledge, and poor governmental and institutional support may prevent estate managers from experimenting with new adaptation options. Policies should, therefore, be aimed at promoting new adaptation options through information exchange between stakeholders and integrating climate change adaptation with Sri Lanka’s national sustainable developmental goals. The primary message of the adaptation analysis in this study is that governmental and institutional support and involvement are critical requirements for facilitating effective adaptation. Findings from the thesis will help inform decision makers of the likely impacts of climate change on plantation cropping systems, and provide insights into barriers to adaptation and potential policy responses to improve the effectiveness of adaptation.

During the past few decades, the basic assumption of agroclimatic zoning, i.e., that agroclimatic conditions remain relatively stable, has been shattered by ongoing climate change. The first aim of this study was to develop a tool that would allow for effective analysis of various agroclimatic indicators and their dynamics under climate change conditions for a particular region. The results of this effort were summarized in the AgriClim software package, which provides users with a wide range of parameters essential for the evaluation of climate-related stress factors in agricultural crop production. The software was then tested over an area of 114,000 km2 in Central Europe. We have found that by 2020, the combination of increased air temperature and changes in the amount and distribution of precipitation will lead to a prolonged growing season and significant shifts in the agroclimatic zones in Central Europe; in particular, the areas that are currently most productive will be reduced and replaced by warmer but drier conditions in the same time the higher elevations will most likely experience improvement in their agroclimatic conditions. This positive effect might be short-lived, as by 2050, even these areas might experience much drier conditions than observed currently. Both the rate and the scale of the shift are amazing as by 2020 (assuming upper range of the climate change projections) only 20–38% of agriculture land in the evaluated region will remain in the same agroclimatic and by 2050 it might be less than 2%. On the other hand farmers will be able to take advantage of an earlier start to the growing season, at least in the lowland areas, as the proportion of days suitable for sowing increases. As all of these changes might occur within less than four decades, these issues could pose serious adaptation challenges for farmers and governmental policies. The presented results also suggest that the rate of change might be so rapid that the concept of static agroclimatic zoning itself might lose relevance due to perpetual change.

Integrating hydrology with climate is essential for a better understanding of the impact of present and future climate on hydrological extremes, which may cause frequent flooding, drought, and shortage of water supply. This study assessed the impact of future climate change on the hydrological extremes (peak and low flows) of the Zenne river basin (Belgium). The objectives were to assess how climate change impacts basin-wide extreme flows and to provide a detailed overview of the impacts of four future climate change scenarios compared to the control (baseline) values. The scenarios are high (wet) summer (projects a future with high storm rain in summer), high (wet) winter (predicts a future with high rainfall in winter), mean (considers a future with intermediate climate conditions), and low (dry) (projects a future with low rainfall during winter and summer). These scenarios were projected by using the Climate Change Impact on HYDRological extremes perturbation tool (CCI-HYDR), which was (primarily) developed for Belgium to study climate change. We used the Soil and Water Assessment Tool (SWAT) model to predict the impact of climate change on hydrological extremes by the 2050s (2036–2065) and the 2080s (2066–2095) by perturbing the historical daily data of 1961–1990. We found that the four climate change scenarios show quite different impacts on extreme peak and low flows. The extreme peak flows are expected to increase by as much as 109% under the wet summer scenario, which could increase adverse effects, such as flooding and disturbance of the riverine ecosystem functioning of the river. On the other hand, the low (dry) scenario is projected to cause a significant decrease in both daily extreme peak and low flows, by as much as 169% when compared to the control values, which would cause problems, such as droughts, reduction in agricultural crop productivity, and increase in drinking water and other water use demands. More importantly, larger negative changes in low flows are predicted in the downstream part of the basin where a higher groundwater contribution is expected, indicating the sensitivity of a basin to the impact of climate change may vary spatially and depend on basin characteristic. Overall, an amplified, as well as an earlier, occurrence of hydrological droughts is expected towards the end of this century, suggesting that water resources managers, planners, and decision makers should prepare appropriate mitigation measures for climate change for the Zenne and similar basins.