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Changes in the agriculture sector are essential to mitigate and adapt to climate change, meet growing food demands, and improve the livelihoods of poor smallholder producers. What agricultural strategies are needed to meet these challenges? To what extent are there synergies among these strategies? This paper examines these issues for smallholder producers in Kenya across several agroecological zones. Several practices emerge as triple wins, supporting climate adaptation, greenhouse gas mitigation, and profitability goals. In particular, integrated soil fertility management and improved livestock feeding are shown to provide multiple benefits across all agroecological zones examined. Triple wins of other agricultural practices are limited to specific agroecological zones. Irrigation and soil and water conservation, for example, are essential for adaptation, mitigation, and profitability in arid areas. The results suggest that agricultural investments targeted toward these triple-win strategies will have the greatest payoff in terms of increased resilience of farm and pastoralist households and global climate change mitigation. To reap the benefits of triple-win strategies will require that policymakers, researchers, and practitioners move away from isolated approaches focused on either adaptation or mitigation or rural income generation toward a more holistic assessment of joint strategies as well as their tradeoffs and synergies. [ABSTRACT FROM AUTHOR]

urate simulation of soil organic carbon (SOC) dynamics is vitally important in researching the carbon cycle in terrestrial ecosystems. Especially, the application of SOC model at the regional scale has major implications for regional and global carbon cycling. This paper addresses the regional simulation for SOC in the surface layer (0~15 cm) of paddy soils in Wuxi and Changzhou, Jiangsu Province, China from 1982~2000 by linking a model of agro-ecosystem SOC dynamic simulation with GIS data on the basis of 100 × 100 m grids. The dataset includes soil profile descriptions and chemical data of 187 paddy soil samples in the Second National Soil Survey of China in 1982 and 352 paddy soil samples taken in 2000. Soil maps at a scale of 1:50,000 were used for the simulation. Results showed that the area of differences between simulated and observed SOC in 2000 (in the range of −3.6 to 3.6 Mg C ha) accounted for 50.6% of the total area. Also, when a 10% and 20% simulated increase, and a 10%, 20% and 30% simulated decrease in harvested crop straw and manure amendments were simulated to test the sensitivity of the model, simulated SOC would range from 10.26 to 50.40 Mg C ha with a standard deviation of 1.6 and 2.5, respectively. It is indicated that a key factor controlling SOC is the amount of residue and manure inputs. As for the assessment model suitability based on soil textures, soil types, and parent materials, the model seemed to perform better for clayey soils, groundwater-related paddy soils and soils derived from alluvial parent material than for loamy soils, surface water-related paddy soils and soil derived from loess material. [ABSTRACT FROM AUTHOR]

The aim of this paper is to improve understanding of the adaptive capacity of European agriculture to climate change. Extensive data on farm characteristics of individual farms from the Farm Accountancy Data Network (FADN) have been combined with climatic and socio-economic data to analyze the influence of climate and management on crop yields and income and to identify factors that determine adaptive capacity. A multilevel analysis was performed to account for regional differences in the studied relationships. Our results suggest that socio-economic conditions and farmcharacteristics should be considered when analyzing effects of climate conditions on farm yields and income. Next to climate, input intensity, economic size and the type of land use were identified as important factors influencing spatial variability in crop yields and income. Generally, crop yields and income are increasing with farm size and farm intensity. However, effects differed among crops and high crop yields were not always related to high incomes, suggesting that impacts of climate and management differ by impact variable. As farm characteristics influence climate impacts on crop yields and income, they are good indicators of adaptive capacity at farm level and should be considered in impact assessment models. Different farm types with different management strategies will adapt differently. [ABSTRACT FROM AUTHOR]

This paper assesses the impact of climate change on irrigated rice yield using B2 climate change scenario from the Regional Climate Model (RCM) and CERES-rice model during 2071-2090. Eight typical rice stations ranging in latitude, longitude, and elevation that are located in the main rice ecological zones of China are selected for impact assessment. First, Crop Estimation through Resource and Environment Synthesis (CERES)-rice model is validated using farm experiment data in selected stations. The simulated results represent satisfactorily the trend of flowering duration and yields. The deviation of simulation within ±10% of observed flowering duration and ±15% of observed yield. Second, the errors of the outputs of RCM due to the difference of topography between station point and grid point is corrected. The corrected output of the RCM used for simulating rice flowering duration and yield is more reliable than the not corrected. Without CO2 direct effect on crop, the results from the assessment explore that B2 climate change scenario would have a negative impact on rice yield at most rice stations and have little impacts at Fuzhou and Kunming. To find the change of inter-annual rice yield, a preliminary assessment is made based on comparative cumulative probability at low and high yield and the coefficient variable of yield between the B2 scenario and baseline. Without the CO2 direct effect on rice yield, the result indicates that frequency for low yield would increase and it reverses for high yield, and the variance for rice yield would increase. It is concluded that high frequency at low yield and high variances [ABSTRACT FROM AUTHOR]

There is growing evidence that, as a result of global climate change, some of the most severe weather events could become more frequent in Europe over the next 50 to 100 years. The paper aims to (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from simulations with global circulation models, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts on agricultural systems and forests in Switzerland. Trends and scenarios project more frequent heavy precipitation during winter corresponding, for example, to a three-fold increase in the exceedance of today's 15-year extreme values by the end of the 21st century. This increases the risk of large-scale flooding and loss of topsoil due to erosion. In contrast, constraints in agricultural practice due to waterlogged soils may become less in a warmer climate. In summer, the most remarkable trend is a decrease in the frequency of wet days, and shorter return times of heat waves and droughts. This increases the risk of losses of crop yield and forage quality. In forests, the more frequent occurrence of dry years may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Some possible measures to maintain goods and services of agricultural and forest ecosystems are mentioned, but it is suggested that more frequent extremes may have more severe consequences than progressive changes in means. In order to effectively decrease the risk for social and economic impacts, long-term adaptive strategies in agriculture and silviculture, investments for prevention, and new insurance concepts seem necessary. [ABSTRACT FROM AUTHOR]

During the recent decade, with the growing recognition of the possibility of climate change and clear evidence of observed changes in climate during 20th century, an increasing emphasis on food security and its regional impacts has come to forefront of the scientific community. In recent times, the crop simulation models have been used extensively to study the impact of climate change on agricultural production and food security. The output provided by the simulation models can be used to make appropriate crop management decisions and to provide farmers and others with alternative options for their farming system. It is expected that in the coming decades with the increased use of computers, the use of simulation models by farmers and professionals as well as policy and decision makers will increase. In India, substantial work has been done in last decade aimed at understanding the nature and magnitude of change in yield of different crops due to projected climate change. This paper presents an overview of the state of the knowledge of possible effect of the climate variability and change on food grain production in India. [ABSTRACT FROM AUTHOR]

Abstract PNNLs Agriculture and Land Use is used to demonstrate the impact of potential changes in climate on agricultural production and land use in the United States. AgLU simulates production of four crop types in several world regions, in 15-yr time steps from 1990 to 2095. Changes in yield of major field crops in the United States, for 12 climate scenarios, are obtained from simulations of the EPIC crop growth model. Results from the HUMUS model are used to constrain crop irrigation, and BIOME3 model is used to simulate productivity of unmanaged ecosystems. Assumptions about changes in agricultural productivity outside the United States are treated on a scenario basis, either responding in the same way as in the United States, or not responding to climate. [ABSTRACT FROM AUTHOR]

Analyzes the potential impacts of climate change on an important negative externality from agriculture, water quality. Construction of a simulation model of maize production within the U.S. Chesapeake Bay Region; Agricultural importance of maize to the region; Carbon dioxide enrichment effects on maize production.

Smallholder farmers in Sub-Saharan Africa are most susceptible to the impacts of climate change, including longer duration dry-spells and more frequent drought. There is a growing literature examining the psychological determinants of various climate adaptation strategies among smallholder farmers but little attention to how psychological factors vary across adaptation decisions and the underlying motivations for these decisions. We assess climate adaptation in terms of five risk management categories outlined by Agrawal (2009). Using a sample of farming households in Kenya (N = 494), we find that while 98% of smallholders believe that various dimensions of climate change pose a significant threat to their livelihood, these beliefs do not necessarily translate into climate actions. Results show that environmental concerns are not salient motivators for or against adaptation strategies, but food insecurity and household expenses are, suggesting a disconnect between climate beliefs and actions. Future research on decision-making related to climate adaptation within semi-arid agroecosystems should consider that while perceptions of climate change are important in shaping climate adaptive actions, they are not necessarily a salient motivator. Climate change is predicted to have significant negative impacts on food security but concerns about food security are what motivate farmers to adopt practices that will prepare them for climate change. [ABSTRACT FROM AUTHOR]

Coastal areas of the Mekong Delta in Vietnam are increasingly experiencing salinity intrusion in freshwater systems, in part due to climate change induced sea-level rise, compromising agricultural production and domestic water supply. In order to determine which development trajectories could result in resilient agro-ecosystems, a study area in Thanh Phu district, Ben Tre province was selected where the influence of salinity intrusion on agro-ecosystem can be studied along spatial and temporal salinity gradients. The district is divided in three sub-regions: sub-region 3, closest to the coastline, is principally dedicated to brackish-water shrimp farming; more inland, sub-region 2 has a mix of rice-shrimp farming; and further inland, sub-region 1, which is protected from salinity intrusion by a system of dykes, is dedicated principally to rice farming. Household and expert interviews, focus group discussions and a review of policy documents were used to capture historical salinity problems as well as shifts in farming systems. Agricultural activities have changed in the last decades, mainly driven by national-level policies. At present, the development of engineered infrastructures is favoured whereas complementary or alternative solutions to increase the resilience of social-ecological systems with respect to salinity intrusion exist. These include regeneration of coastal ecosystems, agronomic measures, upstream flow control and shifts in agro-ecosystems. The latter would increasingly enable farmers to work under the influence of both saline and freshwater systems allowing income diversification. National authorities have an opportunity to change the business as usual mode of tackling water-related problems including extreme events in the Mekong Delta through infrastructure development by looking at these alternative solutions. [ABSTRACT FROM AUTHOR]

Climate change has the potential to be a source of increased variability if crops are more frequently exposed to damaging weather conditions. Yield variability could respond to a shift in the frequency of extreme events to which crops are susceptible, or if weather becomes more variable. Here we focus on the United States, which produces about 40% of the world's maize, much of it in areas that are expected to see increased interannual variability in temperature. We combine a statistical crop model based on historical climate and yield data for 1950-2005 with temperature and precipitation projections from 15 different global circulation models. Holding current growing area constant, aggregate yields are projected to decrease by an average of 18% by 2030-2050 relative to 1980-2000 while the coefficient of variation of yield increases by an average of 47%. Projections from 13 out of 15 climate models result in an aggregate increase in national yield coefficient of variation, indicating that maize yields are likely to become more volatile in this key growing region without effective adaptation responses. Rising CO could partially dampen this increase in variability through improved water use efficiency in dry years, but we expect any interactions between CO and temperature or precipitation to have little effect on mean yield changes. [ABSTRACT FROM AUTHOR]

The effects of climate change will be felt by most farmers in Europe over the next decades. This study provides consistent results of the impact of climate change on arable agriculture in Europe by using high resolution climate data, socio-economic data, and impact assessment models, including farmer adaptation. All scenarios are consistent with the spatial distribution of effects, exacerbating regional disparities and current vulnerability to climate. Since the results assume no restrictions on the use of water for irrigation or on the application of agrochemicals, they may be considered optimistic from the production point of view and somewhat pessimistic from the environmental point of view. The results provide an estimate of the regional economic impact of climate change, as well as insights into the importance of mitigation and adaptation policies. [ABSTRACT FROM AUTHOR]

Many studies reported the coexisting trends of decreasing and increasing pan evaporation in some large scale regions. This study proved that the coexisting trends also occurred in small scale region as well as in large scale region. To discover the important factors governing the incompatible trends of annual pan evaporation, annual climatic data of ten meteorological stations at the Liaohe Delta over recent 45 years were analyzed by the partial correlation analysis, and the results showed the strongest statistically correlation between annual relative humidity and annual pan evaporation. Researches on two extreme cases suggested there was obvious contrary trend between annual relative humidity and annual pan evaporation for one case, in despite of slight contrary trend for another case. Generally, annual relative humidity most likely was an important factor relating to the trend of annual pan evaporation. At the same time, an expanded urbanization and irrigation were seen around these meteorological stations. Urbanization and irrigation exerted opposite effects on pan evaporation, they therefore were speculated to be the ultimately inducements causing unbalanced relative humidity, and led to incompatible pan evaporation. [ABSTRACT FROM AUTHOR]

In the Arkansas River Basin in southeastern Colorado, surface irrigation provides most of the water required for agriculture. Consequently, the region's future could be significantly affected if climate change impacts the amount of water available for irrigation. A methodology to model the expected impacts of climate change on irrigation water demand in the region is described. The Integrated Decision Support Consumptive Use model, which accounts for spatial and temporal variability in evapotranspiration and precipitation, is used in conjunction with two climate scenarios from the Vegetation- Ecosystem Modeling and Analysis Project. The two scenarios were extracted and scaled down from two general circulation models (GCMs), the HAD from the Hadley Centre for Climate Prediction and Research and the CCC from the Canadian Climate Centre. The results show significant changes in the water demands of crops due to climate change. The HAD and CCC climate change scenarios both predict an increase in water demand. However, the projections of the two GCMs concerning the water available for irrigation differ significantly, reflecting the large degree of uncertainty concerning what the future impacts of climate change might be in the study region. As new or updated predictions become available, the methodology described here can be used to estimate the impacts of climate change. [ABSTRACT FROM AUTHOR]