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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]

Extreme events of climate change are increasing, such as droughts and heat waves, causing limitations on growth and yield in relevant food crops, as well as threatening global food security. Brassinosteroids (BRs) are natural or synthetic steroids with significant properties that promote plant growth and development. In the current world scenario, research and solutions that can improve plant tolerance to climate change are strategic to ensure food security. The distinctiveness and novelty of this review lie in its comprehensive and detailed approach to the role of BRs in plants under biotic and abiotic stresses. We consolidate information on the action mechanisms on specific organs, providing detailed experimental conclusions of these plant growth regulators, including also commercial products and concentrations tested aiming to mitigate the adverse effects of the stresses. This practical approach highlights the potential of BRs in agriculture and plant protection against stresses. Additionally, our review presents results with plant models and essential food crops, focusing on multidisciplinary approaches and using physiological, biochemical, nutritional, anatomical and agronomic tools to explain the mechanisms of action of brassinosteroids in plants exposed to abiotic and biotic stresses. [ABSTRACT FROM AUTHOR]

The synchronicity of rain and heat in the summer of China's monsoon region provides sufficient water and heat resources for maize growth. However, the intra-annual distribution of precipitation and the probability of extreme precipitation have been inevitably altered by the ongoing climate change, thus affecting the matching degree between precipitation and crop water requirements (MDPCWR). Evaluating the extent to which the MDPCWR will change in the future is of great importance for food security and the sustainable management of water resources. In this study, considering that different growth stages of crops have different sensitivities to water stress, the AquaCrop model was used to calculate the MDPCWR more accurately. In addition, a cumulative distribution function-transform (CDF-t) method was used to remove the bias of 11 global climate models (GCMs) under two typical emission scenarios (SSP2-4.5 and SSP5-8.5) from phase six of the Coupled Model Intercomparison Project (CMIP6). A comprehensive investigation was conducted on how maize growth, water consumption, and the MDPCWR will respond to future climate change with CO2 concentration enrichment in the Huang–Huai–Hai (3H) region in China by driving a well-tested AquaCrop model with the bias-corrected GCMs outputs. The results indicate the following: (1) The CDF-t method can effectively remove seasonal bias, and it also performs well in eliminating the bias of extreme climate events. (2) Under the SSP2-4.5 scenario, the average maximum temperature will increase by 1.31 °C and 2.44 °C in 2021–2050 and 2051–2080, respectively. The average annual precipitation will increase up to 96.8 mm/year, but it will mainly occur in the form of heavy rain. (3) The increased maize evapotranspiration rate does not compensate for the decreased crop water requirement (up to −32 mm/year), due to a shorter growth cycle. (4) The farmland cultivation layer is not able to hold a significant amount of precipitation, due to the increased frequency of heavy rains, resulting in increased irrigation water requirements for maize over the next two periods, with the maximum value of 12 mm/year. (5) Under different scenarios, the projected future MDPCWR will decrease by 9.3–11.6% due to changes in precipitation patterns and crop water requirements, indicating that it will be more difficult for precipitation to meet the water demand of maize growing in the 3H region. The results can provide comprehensive information to understand the impact of climate change on the agricultural water balance and improve the regional strategy for water resource utilization in the 3H region. [ABSTRACT FROM AUTHOR]

Legume-based livestock forage systems are widespread and socially relevant agroecosystems that are essential for delivering high-quality forage. Therefore, it is critical to determine how climate change and management might affect the functioning of forage agroecosystems. The objective of this study was to explore the potential of sainfoin swards under different management regimes by combining results from an experiment on species diversity effects on yield developed under extreme climatic conditions and a survey of sainfoin (Onobrychis viciifolia Scop.) swards and nutritive value in mountain regions in Catalonia, Western Mediterranean. Our results show that 12–59% of the variability in forage nutritive value parameters was accounted for by management. Young cattle-grazed swards showed higher nutrition quality that decreased faster than sheep-grazed or only mown swards. Mixing sainfoin with orchardgrass increased fiber content (e.g., +22% neutral detergent fiber) and decreased protein (−26%) and lignin (−11%) compared to sainfoin monocultures. However, under the extreme climatic conditions of the last three years, the only diversity effect found on yield was the identity of the species present. We propose that a combination of different sainfoin management regimes might be beneficial regionally for both quality forage production and overall biodiversity conservation, whereas traditional systems may be vulnerable to changing climatic conditions. [ABSTRACT FROM AUTHOR]

The increased frequency of climate extremes associated with ongoing climate change has the potential for significant impacts on maize grain yield in maize-producing regions worldwide. In this study, we used a modeling approach to investigate the effects of different types of climatic extremes on maize grain yield in Northeast China. We combined annual mean air temperature and accumulated precipitation data and divided the climate years into 9 categories, using the 10th and 90th percentiles as extreme thresholds. The climate data were represented by 1 normal climate type, 4 individual climate extremes, and 4 combined climate extremes. Changes in the frequencies of climate extremes and their impacts on maize grain yields were analyzed for two 30-year periods (period I: 1960–1989; period II: 1990–2019) using the Agricultural Production Systems sIMulator (APSIM-Maize). Compared with period I, the occurrences of the normal climate and all 3 cold-related climate extremes (i.e., cold-normal, cold-humid, and cold-dry) decreased during period II, while occurrences of the other climate extremes increased. Moreover, according to the APSIM-Maize model, the estimated yield in the years with a normal climate decreased by 4.01%; the 3 cold-related climate extremes increased yields by 26.56%, 12.10%, and 6.68%, respectively; the 2 warm-related climate extremes (warm-normal and warm-dry) and normal-humid years decreased estimated yields by 6.39%, 24.12%, and 5.10%, respectively. The increase in the occurrence of warm-humid years increased the estimated yield by 11.69%. This work confirms the adverse effects of warmer temperatures in the absence of excess rainfall on grain yield and highlights the importance of extremely dry or wet conditions under normal temperature conditions. [ABSTRACT FROM AUTHOR]

The climate alters pest populations and in turn, pesticide use and cost as well as use of other pest treatments. This paper analyzes the effect of the climate on pesticide expenditures by category, namely: fungicides, herbicides, and insecticides. This is done by econometrically estimating the effects of climate variables such as mean temperature and precipitation as well as the number of hot days, cold days, and wet days on the mean and variance of expenditures by category. The estimates are performed for corn, soybeans, spring and winter wheat, and potatoes. We find that climate factors influence fungicide, herbicide, and insecticide expenditures and that this influence is heterogeneous, varying in nature across crops and pesticide categories. Moreover, we find that climate extremes are more important in determining pesticide expenditures than climate averages in several cases. [ABSTRACT FROM AUTHOR]

Many scholars have conducted in-depth studies on the research area of black soil conservation (BSC) and produced fruitful research results, but there is still a lack of scientific quantitative analysis and objective comprehensive evaluation of the research results. In order to grasp and clarify the current status of BSC research, we explored the trending topics and frontier issues in this research field, as well as the overall evolution trend from 1983 to 2022. Based on the publication information of BSC topics in the core database of Web of Science (WOS), this study utilized the superior tools in two major bibliometric software; they are the VOSviewer and CiteSpace to draw visual maps, such as collaboration networks and keyword co-occurrence maps, to further analyze the research progress and frontiers. The results are as follows: First, research on BSC began in 1983 and can be divided into three phases: the period of nascent research, steady development, and rapid growth. The subject increasingly became an area of research focus in academia, but gradually produced signs of intersection with other disciplines, such as agronomy, biology, and economics. Second, the distribution of research institutions and countries has become more concentrated, forming geographically small research clusters in typical black soil area countries, such as Russia and China, where the centrality of research institutions is higher than 0.20. Research networks have also been initially established between developed and developing countries, such as the United States and China, with a high centrality close to 0.50. Third, the research content is increasingly cross-cutting and systematic, and the research focus can be divided into five major areas, such as black soil distribution and physical and chemical characteristics. Fourth, the research areas cover agronomy, chemistry, geography and other levels, and a more systematic research system has been formed. In the future, it is still necessary to strengthen the establishment of data monitoring systems in black soil areas, the improvement of black soil information database, the assertion of conservation tillage technology and the strengthening of extreme climate early warning network to maintain the soil nutrient content and to guarantee the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Climate change-induced extreme changes are making phytomass yields of extensive grasslands in continental areas increasingly dependent on the season. This situation is exacerbated, inter alia, by the decline in grazing livestock production due to a lack of quality labour, and thus by an increase in the proportion of unused or under-utilised grassland. In our experiments, we have refined the effects of a decade of unused/abandonment, mulch, mowing and meadow utilisation on carbon emissions, soil moisture and soil temperature during two different types of years. We found that unused/abandonment grassland with accumulated duff in the absence of utilization had the highest carbon dioxide emission values in different years, even at lower soil moisture values. Our results confirm the fact that fallow grasslands can be considered a source of risk due to their increased greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

In Ghana, most of the farmers are engaged in small-scale rainfed farming where the success is influenced by the prevailing weather conditions. Current Climate Information Services (CISs) only provide information on rainfall conditions to reduce their farming vulnerability to climate extremes. Access to other practical knowledge, such as soil moisture content would benefit farmers further in the decision-making process. This study aims to assess the role of soil moisture information in farmers' agricultural decision-making and to understand how this information is being perceived, assessed, and applied. Exploratory research, combined with field visits and farmer interviews, was carried out in Gbulung, Napakzoo, and Yapalsi communities in the outskirts of Tamale, northern Ghana in October–December 2021. Results show that soil moisture information is highly important for activities, such as fertilizer application and sowing. Soil moisture information, however, is not readily available to the farmers, causing them to rely solely on their indigenous knowledge to monitor the soil moisture conditions. Our study reveals that developing a CIS embedded with soil moisture advisory module (CIS-SM) will help farmers in conducting strategic and tactical decision-making in their daily farming activities. [ABSTRACT FROM AUTHOR]