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Abstract Systemic changes in environmental conditions, such as climate, can have a significant impact on both natural and human systems. This paper provides an improved understanding of the spatio-temporal variations in underlying climate processes, and the potential effects climate change may have on Vietnam's agricultural sector. Statistical methods were combined with geostatistical techniques to test the statistical significance of long-term trends in the climatic variables, graphically representing the distribution of climate patterns, identifying variations and trends of changes over time and their likely effects on agricultural production. By using records of monthly precipitation and temperature for a relatively long-term period (1975–2014) over a high density of 112 meteorological stations across the country, robust statistical and visual evidence of climatic change throughout Vietnam are provided. The Mann-Kendall trend test confirms the statistically significant long-term trends of rainfall and temperature in many regions across the country. The visual analysis shows remarkable changes in the spatio-temporal distribution patterns of those variables and most of the 'hotspot' areas identified by geostatistical mapping are in areas with confirmed long-term trends. The long-term significant trends are also concentrated in areas with very high proportion of agricultural land, particularly land used for rice production in the Red River and Mekong River deltas. The findings deliver a better understanding of underlying climate processes and impacts across regions of Vietnam and provide a basis to develop effective climate-related policies for agricultural production in response to changing climatic conditions. Highlights • We use data from weather stations at high spatial density recorded over a long period. • Robust visual and statistical evidence of climate change across Vietnam is provided. • We identify key rice-growing areas that are affected with pronounced climatic change. • We evaluate the likely effects of the ongoing climatic change on rice production. [ABSTRACT FROM AUTHOR]

While there is considerable interest in understanding the climate–migration relationship, particularly in the context of concerns about global climatic change, little is known about its underlying mechanisms. In the paper, we combine a rich panel data on annual bilateral international migration flows with an extensive data on climate variability across the countries to investigate in-depth the climate–migration link. We find a positive and statistically significant relationship between temperature and international outmigration only in the most agriculture-dependent countries, consistent with the widely documented adverse impact of temperature on agricultural productivity. Further, the temperature–migration relationship is nonlinear and resembles the nonlinear temperature–yield relationship. In addition, migration flows to current major destinations are especially temperature-sensitive. Policies to address issues related to climate-induced international migration would be more efficient if focused on the agriculture-dependent countries and especially people in those countries whose livelihoods depend on agriculture. [ABSTRACT FROM AUTHOR]

Groundwater is a key resource for global agricultural production but is vulnerable to a changing climate. Given significant uncertainty about future impacts, bottom-up approaches for developing adaptive capacity are a more appropriate paradigm than seeking optimal adaptation strategies that assume a high ability to predict future risks or outcomes. This paper analyses the groundwater management practices adopted at multiple scales in East Anglia, UK, to identify wider lessons for developing adaptive capacity within groundwater management. Key elements are (1) horizontal and vertical integration within resource management; (2) making better use of water resources, at all scales, which vary in space and time; (3) embedding adaptation at multiple scales (from farm to national) within an adaptive management framework which allows strategies and management decisions to be updated in the light of changing understanding or conditions; (4) facilitating the ongoing formation through collective action of local Water Abstractor Groups; (5) promoting efficient use of scarce water resources by these groups, so as to increase their power to negotiate over possible short-term license restrictions; (6) controlling abstractions within a sustainable resource management framework, whether at national (regulatory) or at local (Abstractor Group) scales, that takes account of environmental water needs; and (7) reducing non-climate pressures which have the potential to further reduce the availability of usable groundwater. [Copyright &y& Elsevier]

This paper presents an agent-based simulation (ABS) and cellular automata (CA) coupled model to simulate the spatial evolution of the population of China over the past 2000 years. In the model, agents are used to simulate individuals who live in a geographic environment represented by the CA. The choice to migrate is influenced by climate change, potential agricultural productivity change, and waves of mass migrations. Using the simulation, we can observe the spatial evolution of the population, as well as the shift of the population center of gravity, and we can analyze the driving forces of these changing spatial patterns. [ABSTRACT FROM AUTHOR]

Climate change effects on agricultural yields will be uneven over the world. A few countries, mostly in high latitudes, may experience gains, while most will see average yield decrease. This paper aims to quantify the role of market-mediated adjustments in attenuating the effects of climate change by allowing the expression of the new climate-induced pattern of comparative advantages within and between countries. To do this, we develop a quantitative general equilibrium trade model where the representation of land use choice is inspired from modern Ricardian trade models. We use spatially explicit information from the agronomic literature about potential yields before and after climate change for calibration and counterfactual simulations. The results show that the climate-induced yield changes generate large price movements that incentivize adjustments in production and trade. Both production and trade adjustments contribute to reducing welfare losses globally, with production adjustments making the larger contribution. [ABSTRACT FROM AUTHOR]

Nitrogen has a significant contribution to global warming and its reduction in agriculture is expected to reduce N 2 O emissions having however adverse effects on the productivity of agricultural ecosystems. Maintaining systems productivity with alternative N sources i.e manure and composts could be a strategy also to mitigate N 2 O emissions. In this paper, we present the effect of different N sources (organic and chemical) on field N 2 O emissions and how these emissions are associated with soil available N forms (NH 4 + and NO 3 −) in three different rain-fed crops namely barley, pea and vetch grown in Cyprus for two growing seasons. The daily emissions ranged from −3.11 to 12.3 g N–N 2 O/ha/day, while cumulative emissions ranged from 119 g N–N 2 O/ha to 660 g N–N 2 O/ha depending on crop and nitrogen source type. The emissions showed a seasonal pattern and WFPS has been identified as a critical soil parameter controlling daily N 2 O emissions. The daily N 2 O fluxes in the current study derives mainly from nitrification irrespectively crop type or nitrogen source type. Specific emission factors for each crop cultivated under different N source type were calculated and ranged from 0.03% ± 0.02–0.34% ± 0.09. The application of manure and chemical fertilizers cause similar intensity of N 2 O emissions while compost exhibited the lower emission factors. These findings suggest that composts could be integrated in a nutrient management strategy of rain-fed crops with less N 2 O emissions. The high background emissions found suggest also that other factors than external inputs are associated with N 2 O emissions and further studies including the response of microbial community structure and their contribution and association with N 2 O emissions. • Nitrous oxide emissions are very low in rain-fed Mediterranean like climates. • Emission factors from organic N sources ranged from 0.25 to 0.03%. • Organic manure had similar emission factor compared to ammonium nitrate. • Compost exhibited the lowest N 2 O emissions. • N 2 O fluxes had a seasonal variation and were crop depended. [ABSTRACT FROM AUTHOR]