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Tea (Camellia sinensis L.), as one of the most important cash crops in China, plays an important role in increasing farmers' incomes and guaranteeing a high quality of life. Tea production has been greatly influenced by both climate change and economic development in China. However, without a scientific understanding of the interaction mechanism of climate change and the impetus from rapid economic development on tea production practices in China, it is difficult to take adaptive actions to meet the climate change challenges for the tea industry. In this paper, we firstly assessed the potential impacts of climate change on tea climate suitability by empirical formula calculation using meteorological data; then, the effects from the additional climatic stress due to warming on tea production were detected with the annual statistical tea yield record on a municipal level. The contribution of socioeconomic development to the tea industry was evaluated with the comparison of the movement of China's national economy's and tea industry's gravity center during the period of 1987–2017. Finally, a conceptual adaptation framework was built to demonstrate the interaction mechanisms between climate change, tea production, and the economic development. The results showed that there was a negative impact of climate change on tea production in mainland China, with the percentage of high tea climate suitability (>0.9) areas dropping by 45% to 32%, while opportunities of enlarging the tea cultivating area emerged in the north tea production region where the tea climate suitability increased. We found that the tea planting area expanded northwards from 33° N in 1987 to 35° N in 2017 to take advantage of the favorable climatic resources due to warming, and tea planting decreased at an altitude of 100–400 m while increasing to higher altitude of 400–2000 m to avoid hot temperature damage and seek the optimum environment in high mountainous areas for tea production. In addition, the tea production moved westward along the longitude, decreasing obviously at 117–121° E while increasing significantly at 98–104° E and 107–110° E. Meanwhile, the tea production gravity center showed a westward movement consistent with the national economic gravity center moving trend, which means that tea industry development was driven by multiple socioeconomic factors and climatic forcings. A conceptual framework was built in this paper, aiming to show a robust adaptation mechanism for the tea system to maximize the benefits and minimize the damages from the altered climatic resources under rapid economic development in mainland China. The results in this study would help deepen the understanding of the adaptation process and practices for tea production in mainland China. [ABSTRACT FROM AUTHOR]

Climate change is estimated to substantially reduce crop yields in Sub-Saharan West Africa by 2050. Yet, a limited number of studies also suggest that several adaptation measures may mitigate the effects of climate change induced yield loss. In this paper, we used AquaCrop, a process-based model developed by the FAO (The Food and Agriculture Organization, Rome, Italy), to quantify the risk of climate change on several key cereal crops in the Niger Basin. The crops analyzed include maize, millet, and sorghum under rain fed cultivation systems in various agro-ecological zones within the Niger Basin. We also investigated several adaptation strategies, including changes in the sowing dates, soil nutrient status, and cultivar. Future climate change is estimated using nine ensemble bias-corrected climate model projection results under RCP4.5 and RCP8.5 (RCP--Representative Concentration Pathway) emissions scenario at mid future time period, 2021/25-2050. The results show that on average, temperature had a larger effect on crop yields so that the increase in precipitation could still be a net loss of crop yield. Our simulated results showed that climate change effects on maize and sorghum yield would be mostly positive (2% to 6% increase) in the Southern Guinea savanna zone while at the Northern Guinea savanna zone it is mostly negative (2% to 20% decrease). The results show that at the Sahelian zone the projected changes in temperature and precipitation have little to no impact on millet yield for the future time period, 2021/25-2050. In all agro-ecological zones, increasing soil fertility from poor fertility to moderate, near optimal and optimal level significantly reversed the negative yield change respectively by over 20%, 70% and 180% for moderate fertility, near optimal fertility, and optimal fertility. Thus, management or adaptation factors, such as soil fertility, had a much larger effect on crop yield than the climatic change factors. These results provide actionable guidance on effective climate change adaptation strategies for rain fed agriculture in the region. [ABSTRACT FROM AUTHOR]

Climate-smart agriculture is one of the most important actions for agricultural climate change adaptation, especially in Togo, a sub-Saharan African country with a fragile ecology and where agriculture is profoundly impacted by climate change. Using a multinomial endogenous switching regression (MESR) and a multinomial endogenous treatment effect (METE) approach, we conducted empirical research to identify the factors influencing the adoption decisions of climate-smart agricultural practices (CSAPs) and their impact on household food security among smallholder farmers in Togo. The findings of this study revealed that the adoption of CSAPs by farmers is influenced by a range of factors, such as age, marital status, the household head's gender, engagement in off-farm activities, level of education, farm size, agroecological zone, regional location, land ownership, distance between homestead and farm, access to credit, the presence of agricultural associations and cooperatives, and access to extension agents. On the one hand, the MESR analysis demonstrated a positive correlation between the number of adopted CSAPs and households' food consumption score. Similarly, greater adoption of CSAPs resulted in a significant reduction in the food insecurity experience scale. On the other hand, the METE model portrayed an increase in acceptable food consumption when households adopted up to three CSAPs. Likewise, it significantly alleviated severe food insecurity. Further results based on the propensity score matching technique showed that the adoption of a crop rotation system, utilization of improved varieties of seeds, plant protection products, inorganic fertilizer, organic fertilizer, and irrigation improved adopters' food consumption scores while reducing their level of food insecurity. [ABSTRACT FROM AUTHOR]

The challenge of maintaining sufficient food, feed, fiber, and forests, for a projected end of century population of between 9-10 billion in the context of a climate averaging 2-4 °C warmer, is a global imperative. However, climate change is likely to alter the geographic ranges and impacts for a variety of insect pests, plant pathogens, and weeds, and the consequences for managed systems, particularly agriculture, remain uncertain. That uncertainty is related, in part, to whether pest management practices (e.g., biological, chemical, cultural, etc.) can adapt to climate/CO2 induced changes in pest biology to minimize potential loss. The ongoing and projected changes in CO2, environment, managed plant systems, and pest interactions, necessitates an assessment of current management practices and, if warranted, development of viable alternative strategies to counter damage from invasive alien species and evolving native pest populations. We provide an overview of the interactions regarding pest biology and climate/CO2; assess these interactions currently using coffee as a case study; identify the potential vulnerabilities regarding future pest impacts; and discuss possible adaptive strategies, including early detection and rapid response via EDDMapS (Early Detection & Distribution Mapping System), and integrated pest management (IPM), as adaptive means to improve monitoring pest movements and minimizing biotic losses while improving the efficacy of pest control. [ABSTRACT FROM AUTHOR]

Economic risks for livestock production are caused by volatile commodities and market conditions, but also by environmental drivers such as increasing uncertainties due to weather anomalies and global warming. These risks impact the gross margin of farmers and can stimulate investment decisions. For confined pig and poultry production, farmers can reduce the environmental impact by implementing specific adaptation measures (AMs) to reduce heat stress. A simulation model driven by meteorological data was used to calculate indoor climate for 1981 to 2017. This dataset was extrapolated for a projection in the year 2030. The heat stress was calculated for a business-as-usual livestock building and for several AMs. For 2030, the expected value of the reduction of the gross margin was calculated by EUR 3.98 a−1 per animal place for the business-as-usual scenario. The results show that only energy-saving adaptation measures to reduce the inlet air temperature are appropriate to reduce the economic risk to the level of the year 1980 between EUR 0.03 a−1 and EUR 1.02 a−1 per animal place. The efficiency of other AMs to reduce heat stress is distinctly lower (between EUR 2.62 a−1 and EUR 3.80 a−1 per animal place). The results in this study can support the decision making of farmers concerning adaptation management and investments. It can inform agricultural policy design as well as technological development. [ABSTRACT FROM AUTHOR]

Every decade, a suite of standardized climatological metrics known as climate normals are updated, providing averages of temperature and precipitation data over the previous 30-year period. Although some of these climate normals are directly applicable to agricultural producers, there are additional agroclimate metrics calculated from meteorological data that provide physiologically relevant information for on-farm management decisions. In this study, we identified a suite of energy-based agroclimate metrics and calculated changes over the two most recent normal periods (1981–2010 and 1991–2020), focusing on specialty crop production regions in California. Observed changes in agroclimate metrics were largely consistent with broader global warming trends. While most metrics showed small changes between the two periods, during the 1991–2020 period, the last spring freeze occurred ~5 days earlier as compared to the 1981–2010 period, contributing to a >6 day longer frost-free period in the Sacramento and Salinas Valleys; likewise an additional 6.4 tropical nights (Tn > 20 °C) occurred in the Coachella Valley during the 1991–2020 period. A complementary trend analysis of the agroclimate metrics over the 1981–2020 period showed significant increases in growing degree days across all agricultural regions, while significant increases in heat exposure were found for the Salinas and Imperial Valleys and over the Central Coast region. Moreover, summer reference evapotranspiration increased approximately 40 mm in California's Central Valley during 1981–2020, with implications for agricultural water resources. Quantifying the shifts in these agroclimate metrics between the two most recent 30-year normal periods and the accompanying 40-year trends provides context for understanding and communicating around changing climatic baselines and underscores the need for adaptation to meet the challenge that climate change poses to agriculture both in the future and in the present. [ABSTRACT FROM AUTHOR]

Climate change creates challenges for wild species, but plants have survived and adapted to similar changes in their evolutionary past. Most plants were originally outcrossing, one theoretical genetic reason being that self-fertilization does not create novel recombinants that allow adaptation. Thus selfing seems an evolutionary "dead end". Nevertheless, self-fertilizing plants make up 14% of seed plant species. We offer a new interpretation of a response by self-fertilizing wild species to extreme existential threats, which creates novel recombinant progeny. This proposed mechanism goes beyond reproductive assurance, the usual explanation of selfing. Extreme stress, such as excessive heat within a specific window, first makes plants male-sterile, while female organs remain functional and can receive wind-borne pollen from any of the few nearby stress-tolerant individuals. Thus stress-induced male sterility enables and/or enhances outcrossing in selfing plants. Although in practice this proposed mechanism requires very special circumstances and operates only in certain species with conducive floral traits, we posit that over evolutionary time even such rare events can make a significant lasting impact on a species' survival in changing conditions. This proposed mechanism, which we call Diversity Assurance, allows a population subject to severe stress to sample preferentially those genes that underpin tolerance to that specific stress. These genes are then recombined in subsequent generations, along with the male-sterility-under-stress trait of the female parent. This contributes in part to explain the effective evolution and hence persistence of self-fertilizing species. Diversity Assurance, we propose, is an adaptive mechanism that has been selected under extreme stress, underpinned by a simple loss-of-function of the male reproductive system. It may be triggered not only by heat, but also by other stressors. This proposed mechanism helps to explain why even highly self-fertilizing plant species remain able to respond to environmental changes through triggered outcrossing. [ABSTRACT FROM AUTHOR]