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Climate change vulnerability depends upon various factors and differs between places, sectors and communities. People in developing countries whose subsistence livelihood depends mainly upon agriculture and livestock production are identified as particularly vulnerable. Nepal, where the majority of people are in a mixed agro-livestock system, is identified as the world’s fourth most vulnerable country to climate change. However, there is limited knowledge on how vulnerable mixed agro-livestock smallholders are and how their vulnerability differs across different ecological regions in Nepal. This study aims to test two vulnerability assessment indices, livelihood vulnerability index and IPCC vulnerability index, around the Gandaki River Basin of central Nepal. A total of 543 households practicing mixed agro-livestock were surveyed from three districts, namely Dhading, Syangja and Kapilvastu representing three major ecological zones: mountain, mid-hill and Terai (lowland). Data on socio-demographics, livelihood determinants, social networks, health, food and water security, natural disasters and climate variability were collected and combined into the indices. Both indices differed for mixed agro-livestock smallholders across the three districts, with Dhading scoring as the most vulnerable and Syangja the least. Substantial variation across the districts was observed in components, sub-components and three dimensions (exposure, sensitivity and adaptive capacity) of vulnerability. The findings help in designing site-specific intervention strategies to reduce vulnerability of mixed agro-livestock smallholders to climate change.  相似文献   

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Climate change in Nepal and its impact on Himalayan glaciers   总被引:2,自引:0,他引:2  
Climate change can be particularly hard-hitting for small underdeveloped countries, relying heavily on natural resources for the economy and livelihoods. Nepal is one among these countries, being landlocked, with diverse physiographical characteristics within a relatively small territory and with rugged terrain. Poverty is widespread and the capacity of people and the country to cope with climate change impact is low. The country is dominated by the Asian monsoon system. The main occupation is agriculture, largely based on rain-fed farming practices. Tourism based on high altitude adventures is one of the major sources of income for the country. Nepal has a large hydropower potential. While only 0.75% of the theoretical hydropower potential has been tapped, Nepal can greatly benefit from this natural resource in the future. Climate change can adversely impact upon water resources and other sectors of Nepal. The source of water is mainly summer monsoon precipitation and the melting of the large reserve of snow and glaciers in the Himalayan highlands. Observations show clear evidences of significant warming. The average trend in the country is 0.06°C per year. The warming rates are progressively higher for high elevation locations. The warming climate has resulted in rapid shrinking of majority of glaciers in Nepal. This paper presents state-of-knowledge on the glacial dynamics in the country based on studies conducted in the past in Shorong, Khumbu, Langtang, Dhaulagiri and Kanchenjunga regions of Nepal. We present recent trends in river flow and an overview of studies on expected changes in the hydrological regime due to climate change. Formation, growth and likely outburst of glacial lake are phenomena directly related to climate change and deglaciation. This paper provides a synopsis of past glacial lake outburst floods impacting Nepal. Further, likely impacts of climate change on other sectors such as agriculture, biodiversity, human health and livelihoods are discussed.  相似文献   

4.
The consequences of climate change on smallholder farms are locally specific and difficult to quantify because of variations in farming systems, complexity of agricultural and non-agricultural livelihood activities and climate-related vulnerability. One way to better understand the issues is to learn from the experiences of farmers themselves. Thus, this study aimed to better understand rainfed upland cropping systems in NW Cambodia and to identify practical, social and economic constraints to adoption of known climate adaptation options applicable to local agro-ecosystems. The study also sought to document the climate change perceptions and adaptation options employed by farmers to mitigate the climate risks. A household survey was conducted in the districts of Sala Krau and Samlout in North-west Cambodia in 2013 where 390 representatives of households were randomly selected for interviews, group discussions and field observations. The majority of respondents perceived that changes had occurred in the rainfall pattern such as a later start to the monsoon season, decreasing annual rainfall, increasing frequencies of drought and dry spells, and warmer temperatures. Farmers reported reductions in crop yields of 16–27 % over the five-year period of 2008–2012. However, these reductions were not evident in provincial data for the same period. Farmers claimed climate impacts resulted in significant yield reductions, but they appear not to have an effective strategy to adapt to the changes in climate. Further regional research is required to refine climate change adaptation strategies for rainfed upland cropping systems in Cambodia.  相似文献   

5.
Knowledge of climate change vulnerability and impacts is a prerequisite for formulating locally relevant climate change adaptation policies. A participatory approach has been used in this study to determine climate change vulnerability, impacts and adaptation aspects for the Kangsabati River basin, India. The study approach involved engaging with stakeholders representing state (sub-national), district and community levels, through an interactive brainstorming method, to understand stakeholder perceptions regarding (a) local characteristics which influence vulnerability, (b) climate change impacts and (c) relevant adaptation options. The study reveals that vulnerability varies across upstream, midstream and downstream sections of the river basin. Suggested adaptation options, in this predominantly agricultural basin, are found to be applicable across spatial scales. Stakeholder perceptions, regarding vulnerability and impacts, vary with the level of interaction, academic background and type of experience. Interaction confirms the notion that stakeholders have inherent knowledge regarding adaptation, reveals their preferences and ability to think unconventionally. We discuss limitations of the approach while demonstrating its ability to deliver locally relevant and acceptable adaptation options, which could facilitate implementation. We conclude that engaging stakeholders at multiple levels was highly effective in assessing locally relevant aspects of climate change vulnerability, impacts and applicable adaptation options in the Kangsabati River basin. Based on this assessment, a sub-basin scale is recommended for evaluating these aspects, especially for water resources and agricultural systems, through multi-level stakeholder input.  相似文献   

6.
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes. The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers across the region.  相似文献   

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Factors influencing local people’s attitudes towards conservation of the Koshi Tappu Wildlife Reserve (KTWR) are analyzed using an ordered logit model. The results indicate that households living closer to the KTWR are more likely to reveal negative attitude towards conservation. Similarly, respondents from larger households tend to show negative conservation attitude. Educated respondents and farmers are likely to demonstrate a positive conservation attitude. The results consistently show that households with poor socioeconomic status and greater dependence on the KTWR for firewood, fodder, and raw materials are likely to possess a more negative attitude towards conservation. Poor households may not necessarily be less concerned about conservation, although institutional settings and abject poverty near protected areas appear to affect their attitudes. Sustainable management of protected areas and local support for natural resource conservation would require socioeconomic development.  相似文献   

9.
The objective of this paper is to analyse the impacts of climate change on a pine forest stand in Central Siberia (Zotino) to assess benefits and risks for such forests in the future. We use the regional statistical climate model STARS to develop a set of climate change scenarios assuming a temperature increase by mid-century of 1, 2, 3 and 4 K. The process-based forest growth model 4C is applied to a 200-year-old pine forest to analyse impacts on carbon and water balance as well as the risk of fire under these climate change scenarios. The climate scenarios indicate precipitation increases mainly during winter and decreases during summer with increasing temperature trend. They cause rising forest productivity up to about 20 % in spite of increasing respiration losses. At the same time, the water-use efficiency increases slightly from 2.0 g C l?1 H2O under current climate to 2.1 g C l?1 H2O under 4 K scenario indicating that higher water losses from increasing evapotranspiration do not appear to lead to water limitations for the productivity at this site. The simulated actual evaporation increases by up to 32 %, but the climatic water balance decreases by up to 20 % with increasing temperature trend. In contrast, the risk of fire indicated by the Nesterov index clearly increases. Our analysis confirms increasing productivity of the boreal pine stand but also highlights increasing drought stress and risks from abiotic disturbances which could cancel out productivity gains.  相似文献   

10.
Insurance programmes have been indicated as a tool to reduce the economic risk associated with climate change, and crop growth simulation models can be used effectively to assess future trends in crop insurance payouts. This paper assesses the economic role of increasing weather extremes under future climate change on the expected insurance payouts for durum wheat (Triticum turgidum L. spp. durum) over the Mediterranean basin, focusing attention on the effects of heat stresses (HSs). A crop growth simulation, Sirius Quality version 2 (SQ2), calibrated for three varieties (long, medium and short growth cycle) was applied on seven sites under present (1975–1990) and future climate conditions (2030–2050) obtained from five regional circulation models under SRES scenario A1b. The intensity of HSs at anthesis was included as reducing factor of yield originally simulated by SQ2 calculated according to a specific empirical model. Simulated yields were then fitted to the most appropriate distribution, which was used to calculate the expected payouts according to the probability of yields being below a guaranteed level. We found that the simulated crop yields were, in general, negatively skewed and that Weibull probability density function (PDF), admitting negative skewing, provided the best performances in their fitting. The simulation of HSs modified the original shape of the Weibull PDF by increasing the skewness of the distribution. The results of the insurance model indicated that the modification of crop PDFs induced by HSs led to a general increase in payouts with respect to unstressed conditions, with a marked difference between present (+11 %, on average for the selected sites) and future periods (+25 %). When compared to the present, a general decrease in payouts (?1.1 %) was observed when HSs were not included in the simulations. Conversely, HSs impact resulted in a general increase in payouts (+10.3 %) where the highest increase was detected for the long growth cycle variety (+16.6 %) and the lowest for that with short growth cycle (?1.6 %). These results emphasize the importance of the appropriate characterization of crop yield distribution, the economic implications of HSs in a risk management context and a possible strategy to cope with climate change and variability.  相似文献   

11.
Increasing on-farm crop diversity is one agroecological approach to enhancing food self-sufficiency that helps small-scale farmers keep their food systems stable by reducing risks associated with stressors, such as a pest outbreaks or droughts. But understanding how crop diversity and food self-sufficiency are related is unknown. To explore this complex relation, this study presents household data (n = 1664) from Nepal to test the hypothesis that families with high crop diversity enjoy greater household food self-sufficiency. Data are presented for three districts that are representative of three distinct agroecological regions of the country: (1) Sarlahi, which is affluent, market-oriented, and on the plains; (2) Makwanpur District in the hills, which has well-developed integrated farm production; and (3) the mountainous District of Humla, which has the poorest quality environment and is the most remote. Results show that in the Humla District, families with greater crop diversity were more self-sufficient. In contrast, farmers in Makwanpur, who have already established a high degree of crop diversity based on vegetable production, do not benefit from additional crop diversity in terms of their ability to provide for themselves. Finally, data from Sarlahi show that families’ food self-sufficiency benefits from crop diversification. We conclude that boosting crop diversity is a viable strategy for maintaining stability in food systems, but this varies depending on the accessibility of a farm and, in particular, access to markets.  相似文献   

12.
Forecasting the likely economic losses arising from North Atlantic hurricanes is high on the agenda of both Caribbean and North American stakeholders. This paper develops a general equilibrium framework to conduct an impact assessment of climate change and hurricane formation. General equilibrium analysis accounts for not only primary effects but also feedback effects. The model simulations suggest that output losses occurring due to hurricanes are likely to have economy-wide effects. However, the rural economies of the region are likely to suffer the greatest (relative) effects. The findings of this study suggest that rural livelihoods should be mainstreamed in any adaptation initiatives adopted by the region. Ignoring these neighbourhood features in adaptation plans could negatively impact on poverty and unemployment in rural areas.  相似文献   

13.
Environment, Development and Sustainability - Rainfed farming systems that are prevalent in sub-Saharan Africa are prone to climate change. Most studies have only estimated the impacts of climate...  相似文献   

14.
Forage and more widely grassland systems are difficult to analyze in economic terms because a large proportion of what is produced is not marketed. Economic misestimation of these farm products may dramatically alter projected climate change impacts. This study estimates the economic value of grass and assesses the impact of climatic variations on grassland–livestock systems by taking various environmental and climatic factors into account. Accordingly, grass yield responses to nitrogen inputs (N-yield functions) have been simulated using the grassland biogeochemical PaSim model and then fed into the economic farm-type supply AROPAj model. We developed a computational method to estimate shadow prices of grass production, allowing us to better estimate the effects of climatic variability on grassland and crop systems. This approach has been used on a European scale under two Intergovernmental Panel on Climate Change climate scenarios (AR4 A2 and B1). Results show a significant change in land use over time. Accordingly, due to decreases in feed expenses, farmers may increase livestock, thereby increasing overall greenhouse gas emissions for all scenarios considered. As part of autonomous adaptation by farming systems, N-yield functions extending to pastures and fodders allow us to improve the model and to refine results when marketed and non-marketed crops are considered in a balanced way.  相似文献   

15.
The purpose of this study was to investigate the climate change impacts, vulnerability and adaptive capacity of the electrical energy sector in Cyprus. Spatial vulnerability of the island was assessed using the degree-day indicator to investigate heating and cooling demands in the near future using daily temperature projections from regional climate models (RCMs). Using daily electrical energy consumption data for the present climate, an impact model linking consumption and temperature was constructed and this relationship was projected to the future climate using the data from the RCMs and assuming the same technology use. Our impact model results showed that for the period between November and April (‘cold period’), a decreasing trend in electrical energy consumption is evident due to warmer conditions in the near future, while for the period between May and October (‘warm period’), an increasing trend in electricity consumption is evident as warmer conditions dominate by 2050. Regarding the spatial vulnerability assessment, the cooling degree-day indicator testified that major increases in cooling demand, between 100 and 200 degree-days, are expected in inland and southern regions during the summer in the near future. In addition, increases of about 20–50 degree-days are anticipated during autumn. Conversely, energy demand for heating is projected to decrease during spring and winter, especially in the higher elevation parts of the island. More precisely, reductions of about 30–75 degree-days are projected during spring, while greater reductions of about 60–90 degree-days are expected during winter in heating demand, especially for in the near future. The ability of the energy sector to adapt and follow these changes was deemed to be satisfactory reducing the overall vulnerability of the sector to future climate change.  相似文献   

16.
Despite the low productivity of the extensive agriculture system, Ghana recorded the largest reduction of undernourishment in the past two decades. We used biophysical analysis to determine the efficiency and potentials of the extensive system and its future sustainability. The results indicate that food production in Ghana has increased steadily over the past two decades and correlated highly with cropped area and population (R 2 < 0.85 and 0.82), but not with fertilizer (R 2 = 0.06). Sufficient food production could be sustained in the short term. In the longer term, however, the food situation in Ghana appears precarious if population growth continues while land remains the same.  相似文献   

17.
High population density, inadequate infrastructure and low adaptive capacity have made the urban population of Bangladesh highly vulnerable to climate change. Trends in climate and climate-related extreme events in five major cities have been analyzed in this paper to decipher the variability and ongoing changes in urban Bangladesh. An analysis of 55 years (1958–2012) of daily rainfall and temperature data using nonparametric statistical methods shows a significant increase in annual and seasonal mean daily maximum and minimum temperatures in all five cities. A significant increase in climate-related extreme events, such as heavy rainfall events (>20 mm), hot days (>32 °C) and hot nights (>25 °C), is also observed. Climate model results suggest that these trends will continue through the twenty-first century. Vulnerability of urban livelihoods and physical structures to climate change is estimated by considering certainty and timing of impacts. It has been predicted that public health and urban infrastructures, viz. water and power supply, would be the imminent affected sectors in the urban areas of Bangladesh. Adaptation measures that can be adopted to mitigate the negative impacts of climate change are also discussed.  相似文献   

18.
采用经统计降尺度与偏差订正的4种全球气候模式(GFDL-ESM2M,HadGEM2-ES,IPSL-CM5A-LR和MIROC5)1861 ~ 2005年的历史气候模拟试验和2006 ~ 2018年的RCP4.5情景预估资料,驱动SWAT水文模型,分析了1861~2018年乌江流域气候变化特征及其对径流的影响.同时,采用1861~2018年4种全球气候模式在工业革命前控制试验(piControl)数据,对比分析了"自然"和"人为+自然"强迫下流域气候及径流变化的差异.研究结果表明:(1)1861~2018年乌江流域平均气温呈现显著上升趋势,气温倾向率为0.03℃/10a;降水呈显著下降趋势,降水倾向率为-10.9 mm/10a.流域主要水文控制站武隆站年平均流量呈显著下降趋势,倾向率为-20.8 m3/s/10a;四季平均流量倾向率分别为-10.8、-46.1、-20.1、-5.9 m3/s/10a,均呈显著下降趋势;枯水极值流量倾向率为-7.6 m3/s/10a,丰水极值流量倾向率为-43.5 m3/s/10a,下降趋势显著.(2)"自然"强迫控制试验下,1861~2018年乌江流域年平均气温无明显变化趋势;降水则为不显著上升趋势,倾向率为1.9 mm/10a;年平均流量呈微弱上升趋势,倾向率为0.1 m3/s/10a;四季平均流量倾向率分别为-1.1、-18.6、11.0、8.9 m3/s/10a,春季平均流量不显著下降,夏季显著下降,秋季不显著上升,冬季显著上升;枯水极值流量倾向率为2.5 m3/s/10a,丰水极值流量为-9.5 m3/s/10a,变化趋势均不显著.(3)相对"自然"强迫序列,人类活动引起的气候变化导致1861 ~ 2018年乌江四季平均流量分别减少7.1%、9.7%、8.7%、11.9%;枯水与丰水极值流量分别下降9.3%和5.0%.  相似文献   

19.
A simple model of yield was used along with climate scenarios to assess the impact of climate change on grain maize productivity and associated economic risk in Switzerland. In a first application, changes in the precipitation regime alone were shown to affect the distribution of yield considerably, with shifts not only in the mean but also in the standard deviation and the skewness. Production risk was found to respond more markedly to changes in the long-term mean than in the inter-annual variability of seasonal precipitation amounts. In a further application, yield projections were generated with respect to a full climate scenario, with the emission pathway as specified in the IPCC A2 scenario. Anticipation of the sowing date was found to reduce the negative impact of climate change on yield stability, but was not sufficient to ensure average productivity levels comparable to those observed at present. We argued that this was caused by the reduction in the duration of the growing season, which had a stronger impact than suggested by previous studies. Assuming no change in price relations, the results also revealed a strong increase in production risk with climate change, with more than a doubling in the probability of yield falling short of a critical threshold as compared to today’s situation.  相似文献   

20.
The (137)Cs method was employed to investigate the recent historical rate of sediment deposition on a lowland alluvial floodplain in the Falefa River basin, Upolu Island, Samoa. Caesium stratigraphy in the floodplain sediment profile was clearly defined, with a broad peak at 145-175 cm depth. The measured rate of vertical accretion over the last 40 years is 4.0+/-0.4 cm per year. This rate exceeds observations in humid environments elsewhere, but is similar to that recorded on other tropical Pacific Islands. Available flow data for the Vaisigano River in Samoa give a 'near-catastrophic' index value of 0.6 for flood variability. This is associated with the occurrence of tropical cyclones and storms in the Samoa area. Large floods therefore probably contribute to the high rate of floodplain sedimentation on Upolu Island. A small but growing body of evidence suggests that fluvial sedimentation rates on tropical Pacific islands are some of the highest in the world.  相似文献   

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