关键词： adaptation   agricultural system   climate change   irrigation   crop model   hydrologic model  

摘要： Replacing a rainfed cropping system with an irrigated one is widely assumed to be an effective measure for climate change adaptation. However, many agricultural impact studies have not necessarily accounted for the space-time variations in the water availability under changing climate and land use. Moreover, many hydrologic and agricultural assessments of climate change impacts are not fully integrated. To overcome this shortcoming, a tool that can simultaneously simulate the dynamic interactions between crop production and water resources in a watershed is essential. Here we propose the regional production and circulation coupled model (CROVER) by embedding the PRYSBI-2 (Process-based Regional Yield Simulator with Bayesian Inference version 2) large-area crop model into the global water resources model (called H08), and apply this model to the Songhua River watershed in Northeast China. The evaluation reveals that the model's performance in capturing the major characteristics of historical change in surface soil moisture, river discharge, actual crop evapotranspiration, and soybean yield relative to the reference data during the interval 1979-2010 is satisfactory accurate. The simulation experiments using the model demonstrated that subregional irrigation management, such as designating the area to which irrigation is primarily applied, has measurable influences on the regional crop production in a drought year. This finding suggests that reassessing climate change risk in agriculture using this type of modeling is crucial not to overestimate potential of irrigation-based adaptation.

关键词： climate change impacts   agricultural modeling   forestry modeling   mitigation scenarios   EPIC   MC1   FASOM-GHG  

摘要： Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been numerous studies of climate change impacts on agriculture or forestry, but relatively little research examining the long-term net impacts of a stabilization scenario relative to a case with unabated climate change. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from $32.7 billion to $54.5 billion over the period 2015-2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative mitigation and adaptation actions.

关键词： Greenhouse gas mitigation   Domestic policy   Trade policy  

摘要： Using a mathematical programming model of Norwegian agriculture, we explore interconnections between trade liberalization and reductions in greenhouse gas (GHG) emissions. We show that the Doha Round proposals for a new agreement on agriculture through the World Trade Organization would not generate significant reductions in emissions. Further trade liberalization would reduce emissions by cutting agricultural production but would not change production methods. Imposing a carbon tax would lead both to a reduction in output and the extensification of production. In contrast, if farmers are allowed to claim a credit for carbon sequestration the effect is to intensify agricultural production.

关键词： agriculture   Chachapoya   charcoal   fossil pollen   human impacts   late Holocene   montane forest   northern Peru   paleoecology  

摘要： The steep, wet, forested, slopes of the mid-elevation Andes have often been dismissed as inimical to human occupation. A lack of ancient lakes in these habitats has limited the availability of paleoecologists to contribute to this discussion. Here, we present fossil pollen and charcoal data from Lake Pomacochas in northern Peru, which is a 70-m-deep lake lying at 2100m a.s.l. We present a c. 3500-year history of both significant climate change and site occupancy by humans. Maize pollen is present in sediments throughout much of this record, though there are times when its cultivation is either abandoned, or moves back from the shoreline, for example, between c. 3500 and 2700 cal. yr BP and post 1200 cal. yr BP. By comparing our record with isotopic data derived from cave calcite we are able to show that dry times favored maize cultivation in this setting. In the last 1200years, large-scale social changes in the Andes, such as the emergence of the Chachapoya culture and the invasion of Europeans, appear to be reflected in the fossil pollen and charcoal record.

关键词： Climate change   food and nutrition security   science for sustainable agriculture  

摘要： At the time of India's independence in 1947, India's food production for national food security was highly insufficient. Malthusian scourge in the backdrop of Bengal famine of 1943 was looming. It was at a time of critical food shortage in the 1960s, commodity-centric exploitative agriculture, miscalled as Green Revolution, was ushered in by Swaminathan-Borlaug partnership. It changed India's image then as begging bowl to bread basket! As had been foreseen and forewarned, the Green Revolution resulted in environmental degradation, enhanced social inequities and had little to do with sustainable agriculture and rural development. With the lessons learnt, Swaminathan developed a systems approach-based evergreen revolution to achieve productivity in perpetuity without accompanying environmental and social harm. It is also designed to fight both the famines of food and rural livelihoods with the help of ecotechnologies having pro-nature, pro-poor, pro-women and pro-livelihood orientation. The present article elaborates these aspects.

关键词： Knowledge brokering   Climate change   Landuse   Agriculture   Computer modelling  

摘要： This article applies a 'knowledge brokering' approach to contextualise the development of an integrated computer modelling tool into the real world policy context of adaptation of agriculture to climate change at the EU level. In particular, the article tests a number of knowledge brokering strategies described and theorised in the literature, but seldom empirically tested. The article finds that while the policy context can be used to identify a theoretically informed knowledge brokering strategy, in practice a strategy's 'success' is more informed by practical considerations, such as whether the tool development process is knowledge or demand driven. In addition, in practice the knowledge brokering process is found to be dynamic and messy, which is not always apparent in the literature. The article goes on to question the perception that there is always a need (or a desire) to bridge the gap between researchers and policy makers in the tool development process. Rather than a problem of design and communication, the science policy interface may be characterised more by a high level of competition between researchers and research organisations to have their tool legitimised by its use in the policy making process. (C) 2014 Elsevier Ltd. All rights reserved.

摘要： Climate change is expected to have numerous and complex impacts on water resources, with consequences for agricultural production through changes in crop water requirements;the availability and quality of water;and increases in the frequency and severity of extreme weather events such as droughts and floods. Although there is substantial uncertainty about the magnitude of impacts, especially at the local level, this does not call for inaction. On the basis of the recent work undertaken by OECD in this area, we identify and discuss three main dimensions for a comprehensive adaptation strategy for agricultural water management: i) creating an enabling environment to foster on-farm adaptive capacities through policies targeted at innovation, education, and advisory and extension services;ii) improving agricultural water management through the development of flexible and robust instruments, such as water pricing and water markets, to deal with both short-run water shortages and long-run water stress;iii) developing and improving risk management tools for droughts and floods to ensure that the true cost of risks is signalled to farmers while at the same time improving the efficiency of risk allocation. We highlight the importance of policy coherence in recognising the linkages between climate change adaptation and mitigation.

关键词： climate   agriculture   economics   yields   prices   trade  

摘要： Previous studies have combined climate, crop and economic models to examine the impact of climate change on agricultural production and food security, but results have varied widely due to differences in models, scenarios and input data. Recent work has examined (and narrowed) these differences through systematic model intercomparison using a high-emissions pathway to highlight the differences. This paper extends that analysis to explore a range of plausible socioeconomic scenarios and emission pathways. Results from multiple climate and economic models are combined to examine the global and regional impacts of climate change on agricultural yields, area, production, consumption, prices and trade for coarse grains, rice, wheat, oilseeds and sugar crops to 2050. Wefind that climate impacts on global average yields, area, production and consumption are similar across shared socioeconomic pathways (SSP 1, 2 and 3, as we implement them based on population, income and productivity drivers), except when changes in trade policies are included. Impacts on trade and prices are higher for SSP 3 than SSP 2, and higher for SSP 2 than for SSP 1. Climate impacts for all variables are similar across low to moderate emissions pathways (RCP 4.5 and RCP 6.0), but increase for a higher emissions pathway (RCP 8.5). It is important to note that these global averages may hide regional variations. Projected reductions in agricultural yields due to climate change by 2050 are larger for some crops than those estimated for the past half century, but smaller than projected increases to 2050 due to rising demand and intrinsic productivity growth. Results illustrate the sensitivity of climate change impacts to differences in socioeconomic and emissions pathways. Yield impacts increase at high emissions levels and vary with changes in population, income and technology, but are reduced in all cases by endogenous changes in prices and other variables.