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The increasingly inter-connected global food system is becoming more vulnerable to production shocks owing to increasing global mean temperatures and more frequent climate extremes. Little is known, however, about the actual risks of multiple breadbasket failure due to extreme weather events. Motivated by the Paris Climate Agreement, this paper quantifies spatial risks to global agriculture in 1.5 and 2 °C warmer worlds. This paper focuses on climate risks posed to three major crops - wheat, soybean and maize - in five major global food producing areas. Climate data from the atmosphere-only HadAM3P model as part of the "Half a degree Additional warming, Prognosis and Projected Impacts" (HAPPI) experiment are used to analyse the risks of climatic extreme events. Using the copula methodology, the risks of simultaneous crop failure in multiple breadbaskets are investigated. Projected losses do not scale linearly with global warming increases between 1.5 and 2 °C Global Mean Temperature (GMT). In general, whilst the differences in yield at 1.5 versus 2 °C are significant they are not as large as the difference between 1.5 °C and the historical baseline which corresponds to 0.85 °C above pre-industrial GMT. Risks of simultaneous crop failure, however, do increase disproportionately between 1.5 and 2 °C, so surpassing the 1.5 °C threshold will represent a threat to global food security. For maize, risks of multiple breadbasket failures increase the most, from 6% to 40% at 1.5 to 54% at 2 °C warming. In relative terms, the highest simultaneous climate risk increase between the two warming scenarios was found for wheat (40%), followed by maize (35%) and soybean (23%). Looking at the impacts on agricultural production, we show that limiting global warming to 1.5 °C would avoid production losses of up to 2753 million (161,000, 265,000) tonnes maize (wheat, soybean) in the global breadbaskets and would reduce the risk of simultaneous crop failure by 26%, 28% and 19% respectively. • Climate data from the atmosphere-only HadAM3P model were used to estimate the risks of climatic extreme events in the global breadbaskets. • To analyse the risks of simultaneous breadbasket failure, the copula methodology was applied. • Projected wheat, maize and soybean yield losses in the global breadbaskets increase disproportionately between 1.5 and 2 °C global warming. • The highest simultaneous climate risk increase in the breadbaskets between the two warming scenarios was found for wheat, followed by maize and soybean. [ABSTRACT FROM AUTHOR]

Production of pork, the most consumed meat globally, is estimated to emit 668 m tonnes CO 2 -eq of greenhouse gases each year. Amongst various production systems that comprise the pig industry, grain-based intensive production is widely regarded as the largest polluter of the environment, and thus it is imperative to develop alternative systems that can provide the right balance between sustainability and food security. Using an original dataset from the Republic of Ireland, this paper examines the life-cycle environmental impacts of representative pig farms operating under varying production efficiencies. For the baseline farm with an average production efficiency, global warming potential (GWP), acidification potential (AP) and eutrophication potential (EP) per kg carcass weight departing the slaughterhouse were estimated to be 3.5 kg CO 2 -eq, 43.8 g SO 2 -eq and 32.1 g PO 4 -eq, respectively. For herds with a higher production efficiency, a 9% improvement in feed conversion ratio was met by 6%, 15% and 12% decreases in GWP, EP, AP, respectively. Scenario and sensitivity analyses also revealed that (a) a switch to high-protein diets results in lower GWP and higher AP and EP, and (b) reducing transportation distances by sourcing domestically produced wheat and barley does not lower environmental impacts in any notable manner. To improve cross-study comparability of these findings, results based on an auxiliary functional unit, kg liveweight departing the farm gate, are also reported. [ABSTRACT FROM AUTHOR]

Food production is one of the main contributors to climate change, but is also vulnerable to the resulting stressors, which is well documented for agriculture and fisheries. Attention is now turning to the rapidly growing aquaculture sector and its vulnerability to a changing climate. Here we explore the extent to which climate stressors and aquaculture, and concomitant adaptation strategies, are studied in science and addressed in public media (news) to assess focus and attribution of climate change. We reviewed 553 scientific publications and 228 news media articles on climate stressors, impacts, and adaptation approaches with respect to aquaculture. Results indicate that coverage in the scientific community of climate stressors on aquaculture have not kept pace with growth of production in the sector, especially compared to agriculture and fisheries. Temperature, sea level rise, and ocean acidification were most often the focus in science (44%) and news (42%), suggesting some alignment. Combined coverage tended to revolve around Asia, Europe, and North/Central America (70%) and at least 10 countries' science and news linked current impacts on aquaculture to climate change. The majority of scientific articles addressing adaptation were regional rather than global, and emphasized governance and institutional strategies over technological solutions. In all, this research highlights the comparatively nascent focus of climate change implications for aquaculture, narrow emphasis of stressors, but fairly representative coverage of regions with more aquaculture. Our work highlights the need for more research and public awareness of the social and ecological climate change threats and impacts on, and adaptive strategies for aquaculture. • Temp & sea level rise threats to aquaculture were the main focus in science & news. • Focus on Asia, Europe, & N./C. America accounted for 70% of studies. • At least 10 countries linked current impacts on aquaculture to climate change. • Global papers cited technology for adaption, while regional papers cited governance. [ABSTRACT FROM AUTHOR]

The co-culture of rice and poultry/aquatic animals has become a popular strategy to ensure the critical ecological functions and economic benefits of this ecosystem in recent years. Yet, quantitative synthetic effects of co-culture models on ecological functions and economic benefits in paddy fields are poorly understood. This study conducted a meta-analysis of 4707 observations from 224 published papers on the outcomes of co-culture models in paddy fields. On aggregate, co-culture models significantly reduced CH 4 emissions by 14.8 % as compared with rice monoculture, but did not affect rice yields, N 2 O emissions, and greenhouse gas intensity (GHGI). However, significant differences in rice yields, CH 4 emissions, GHGI, and economic benefits were observed among various co-culture models and rice-growing regions. Particularly, the co-culture models in East Asia significantly increased rice yields (+2.2 %), reduced CH 4 emissions (–22.1 %), and GHGI (–9.4 %). Importantly, co-culture models improved rice grain quality. Furthermore, co-culture models increased soil fertility (7.8–16.2 %), nutrients content in paddy water (26.2–87.0 %), and net ecological and economic benefits (31.7–71.1 %), while decreasing diseases, pests, and weeds (37.0–84.6 %) in paddy fields. Additionally, we suggest that the production of poultry or aquatic animals that alters input and output would increase net income, and it is necessary to develop co-culture models in paddy fields according to regional differences in the agricultural environment. Therefore, our study provides a reference for maximizing ecological and economic benefits of suitable co-culture models in rice-planted areas. • Compared with rice monoculture, co-culture models significantly reduced CH 4 emissions by 14.8 %. • Co-culture models improved rice grain quality. • Co-culture models reduced water quality, though they improved soil fertility, controlled diseases, pests, and weeds, and generated economic benefits. • It is necessary to develop co-culture models in paddy fields according to regional differences in the agricultural environment. [ABSTRACT FROM AUTHOR]

Abstract: Recently increasing studies suggest that a comprehensive assessment of cropping practices impacts on greenhouse gas (GHG) emissions at yield-scale will benefit cropping technique innovation and policy selection for higher-yield with less-emissions. In this paper, we conducted a meta-analysis to quantify the impacts of rice cropping practices on the global warming potential (GWP) of GHG emissions at yield-scale rather than area-scale in China. The results showed that the yield-scaled GWP of Chinese major rice cropping systems during rice growing season was in the order: double rice cropping system (1188.9kg CO2 equiv.Mg−1)>rice-upland crop rotation system (777.0kg CO2 equiv.Mg−1)>single rice cropping system (346.7kg CO2 equiv.Mg−1). Nitrogen fertilization (50–300kgNha−1) significantly increased rice yield with slight increments in the GWP of CH4 and N2O emissions, resulting in significant reductions in the yield-scaled GWP. The greatest reduction occurred at the application rate of 150–200kgNha−1 by 37% as compared to the non-fertilization control. For organic amendments, biogas residue application had no significant effect on the yield-scaled GWP, while manure application and straw recycling significantly increased the yield-scaled GWP by 54% and 154%, respectively. Intermittent irrigation significantly reduced yield-scaled GWP by 59% largely because of a significant reduction in CH4 emission and a significant increment in rice yield. No-tillage showed lower CH4 emission with similar rice yield in comparison with the conventional tillage, resulting in a reduction in yield-scaled GWP by 20%. These results indicate that there is a great potential to meet the new objective of higher-yield with less-GHG emissions through innovating rice cropping technique. More efforts should be paid on the field observations of GHG emissions during non-rice growing season, so as to perform a life-cycling assessment of GHG emissions from rice fields at yield scale under different cropping systems. [Copyright &y& Elsevier]

Abstract: This paper provides an introduction to the Special Issue on “Climate Change and Coupling of Macronutrient Cycles along the Atmospheric, Terrestrial, Freshwater and Estuarine Continuum”, dedicated to Colin Neal on his retirement. It is not intended to be a review of this vast subject, but an attempt to synthesize some of the major findings from the 22 contributions to the Special Issue in the context of what is already known. The major research challenges involved in understanding coupled macronutrient cycles in these environmental media are highlighted, and the difficulties of making credible predictions of the effects of climate change are discussed. Of particular concern is the possibility of interactions which will enhance greenhouse gas concentrations and provide positive feedback to global warming. [Copyright &y& Elsevier]

Abstract: To learn the historical response of cropping system to climate change will benefit the strategy decision of future cropping adaptation. In this paper, we conducted an integrated analysis of the climate records of seventy-two meteorological stations and the records of crop yields over the period 1970–2009 in Northeast China. It was found that over these forty years, the daily mean, maximum and minimum temperatures during crop growing season increased on average by 0.34°C, 0.28°C, 0.43°C every ten years, respectively. No significant change in the precipitation was found, although the differences between years were large. After de-trending the agronomic technique contributions to the increments of crop yields, the historical warming had led to great annually increments of 16.6kgha−1, 15.5kgha−1 and 3.2kgha−1 in rice, corn and soybean yields, respectively. According to the historical warming level, present cropping boundaries can be theoretically extended northward about 80km with a prolonged growing period by 10 days compared to the 1970s. Actually, the growth durations of newly approved varieties of rice, corn and soybean have really prolonged by 14.0 days, 7.0 days and 2.7 days since the 1950s, respectively. The actual growing periods of rice and corn have also respectively prolonged by 6 days and 4 days due to the adjustment of sown and harvest dates by the farmer since 1990s. The existing rice cropping region has been extended northward 80km in the 2006 compared to the 1970. These actual responses were consistent with the theoretical calculation according to the historical warming trends. Our results demonstrate that cropping system owns the potential to progressively and actively adapt to the global warming for high yield through a comprehensive strategy. [Copyright &y& Elsevier]

Abstract: China is one of the most important rice production countries in the world, and maintaining high rice productivity in China is very important for world food security. While previous studies showed that rice production in China has been and will be negatively impacted by global warming, the confounding effects of climatic change, variety improvement and agronomic managements have not been separately investigated. In this paper we combine an analysis of climate and rice growth data with crop modeling to investigate the impact of changes in climate, rice varieties, and agronomic management on rice productivity at four sites (Wuchang, Xinyang, Zhenjiang and Hanyuan) in China. The results showed a significant increase in minimum temperature during all rice growth stages at Wuchang and Zhenjiang, and from heading to maturity at Xinyang, but little change at Hanyuan. Global warming would have led to a reduction in the length of rice growing period and a reduction in grain yield at all study sites, if no varietal changes had occurred. However, the adoption of new rice varieties stabilized growing duration, increased harvest index and grain yield at three of the four sites. In the face of future warming, a planned breeding effort may be needed to offset the negative impact of future climate change. [Copyright &y& Elsevier]