Revised Universal Soil Loss Equation(RUSLE) model coupled with transport limited sediment delivery(TLSD) function was used to predict the longtime average annual soil loss, and to identify the critical erosion-/deposi...Revised Universal Soil Loss Equation(RUSLE) model coupled with transport limited sediment delivery(TLSD) function was used to predict the longtime average annual soil loss, and to identify the critical erosion-/deposition-prone areas in a tropical mountain river basin, viz., Muthirapuzha River Basin(MRB; area=271.75 km^2), in the southern Western Ghats, India. Mean gross soil erosion in MRB is 14.36 t ha^(-1) yr^(-1), whereas mean net soil erosion(i.e., gross erosion-deposition) is only 3.60 t ha^(-1) yr^(-1)(i.e., roughly 25% of the gross erosion). Majority of the basin area(~86%) experiences only slight erosion(<5 t ha^(-1) yr^(-1)), and nearly 3% of the area functions as depositional environment for the eroded sediments(e.g., the terraces of stream reaches, the gentle plains as well as the foot slopes of the plateau scarps and the terrain with concordant summits). Although mean gross soil erosion rates in the natural vegetation belts are relatively higher, compared to agriculture, settlement/built-up areas and tea plantation, the sediment transport efficiency in agricultural areas and tea plantation is significantly high,reflecting the role of human activities on accelerated soil erosion. In MRB, on a mean basis, 0.42 t of soil organic carbon(SOC) content is being eroded per hectare annually, and SOC loss from the 4th order subbasins shows considerable differences, mainly due to the spatial variability in the gross soil erosion rates among the sub-basins. The quantitative results, on soil erosion and deposition, modelled using RUSLE and TLSD, are expected to be beneficial while formulating comprehensive land management strategies for reducing the extent of soil degradation in tropical mountain river basins.展开更多
Climate change is impacting climate sensitive rural livelihood systems. Exposure, sensitivity, and adaptive capacity of agricultural livelihoods to climate variability and change differ across agro-ecologies and these...Climate change is impacting climate sensitive rural livelihood systems. Exposure, sensitivity, and adaptive capacity of agricultural livelihoods to climate variability and change differ across agro-ecologies and these pose a challenge to climate resilient development strategy. This study assesses agro-ecology specific vulnerability of smallholder farmers to climate change and variability in the Dabus Watershed (North-west Ethiopia), based on a survey of 734 farm households complemented with focus group discussion and key informant interviews. Recognizing the physiographic and climatic diversity that exists across agro-ecologies in the study area, Livelihood Vulnerability Index (LVI) framed within the United Nations Intergovernmental Panel on Climate Change (IPCC) vulnerability framework (LVI-IPCC) is adapted to assess agro-ecology specific vulnerability in two local agro-ecologies, namely wet lowland and dry lowland. For each agro-ecology, exposure, sensitivity and adaptive capacity indices as well as LVI-IPCC vulnerability score was calculated. The result shows that the dry lowland agro-ecology has a relatively higher exposure and sensitivity to climate stresses with a comparatively limited adaptive capability. On the other hand, the wet lowland agro-ecology exhibits intermediate vulnerability with a relatively lower perceived exposure and higher adaptive capacity. Higher exposure relative to adaptive capacity resulted in a positive LVI-IPCC score in the dry lowland agro-ecology and positioned it in more vulnerable level than the wet lowland. A higher adaptive capacity relative to exposure unveils a negative LVI-IPCC score for the wet lowland agro-ecology and positioned it in a moderate vulnerability category. In line with the findings, there is a need to set agro-ecology specific priorities for intervention that is most needed to cop up with the effects of climate variability and change in each agro-ecology. Climate risk exposure levels can be reduced through timely provision of climate specific information and early warning systems aimed at enhancing preparedness of farm households to extreme events. It is also crucial to expand availability of infrastructural facilities such as market, health services, and veterinary services so as to enhance adaptive capacity. Supporting alternative livelihood options and enhancing water harvesting practices for supplementary irrigation also call policy attention.展开更多
The objective of this paper was to determine the factors that influence farmers＇ decision to use two categories of sustainable land management （SLM） practices as adaptation strategy to climate change in the North-W...The objective of this paper was to determine the factors that influence farmers＇ decision to use two categories of sustainable land management （SLM） practices as adaptation strategy to climate change in the North-West Ethiopia. It was based on analysis of data collected from 734 farm household heads and employed probit regression model to analyze the determinants of adaptation to climate change through SLM measures. Based on the model result, factors, like perception of climate change, exposure to adaptation techniques, education, perception of land degradation, slope, land prone to degradation, number of parcels, crop enterprise income, land size, farm distance, economically active family size and agro-ecology are found important in determining farmers＇ decision to use structural land management practices. Likewise, perception of climate change, exposure to adaptation, farming experience, slope, crop enterprise income, land prone to degradation and agro-ecology are found important in affecting farmers＇ decision to use non-structural land management practices as adaptation measure. Therefore, in line with the findings of the analysis, any intervention that promotes use of land management practices as adaptation strategy should take into account agro-ecology specific factors that are relevant to the nature of the land management practices. Moreover, since scaling up of SLM practices as adaptation strategy is resource intensive, it requires both public and non-public investment for providing technological support and raising awareness. Failure to do so would adversely affect crop productivity and exacerbate food insecurity problems at farm household level.展开更多
The establishment of the environmental management system in the financial sector can be effectively promoted through the introduction of the environmental protection concept and its implementation by the financial sec...The establishment of the environmental management system in the financial sector can be effectively promoted through the introduction of the environmental protection concept and its implementation by the financial sector.The impact of a sustainable development system on the sector is analyzed in this article from three aspects:environmental risk assessment,financing support for environmental protection projects,and financial services to environmentally friendly corporations and individuals.Influential factors on the development of the environmental management system in China’s financial sector are discussed from the perspective of various entities such as financial institutions,financial regulation authorities,environmental protection departments,corporations,and the public.It is pointed out that China’s financial sector is now in the transitional phase from a defensive attitude to a preventive attitude.Strengthening governmental guidance,the supervision of regulators as well as public awareness of environmental protection should be used to enhance the initiative in the development of the environmental management system in the Chinese financial sector.展开更多
Awareness of how soil properties vary over agroecosystems(AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study exam...Awareness of how soil properties vary over agroecosystems(AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study examined the characteristics of soil quality attributes and implications for agriculture in the Choke Mountain watershed in Ethiopia. Forty-seven composite soil samples(0–20 cm deep) were collected from lowland and valley fragmented(AES 1),midland plain with black soil(AES 2), midland plain with brown soil(AES 3),sloppy midland land(AES 4), and hilly and mountainous highlands(AES 5).Ten of 15 soil quality properties were significant(P < 0.05 or 0.01), including silt, exchangeable bases, cation exchange capacity, percent base saturation,p H, organic matter, total nitrogen and available phosphorous(P) across the five AES. However, all properties were variable with coefficients of variation from 7%(total porosity) to 169%(available P) across the AES. Although AES 2and 3 are affected by waterlogging and acidity, these two have better prospects for agriculture, but AES 1, 4, and 5 are unsuitable for agriculture because of soil erosion. Therefore, appropriate and applicable soil management strategies, particularly lime application and organic fertilizer, are fundamental to reversing soil acidity and improving soil fertility.展开更多
This study aims to measure how well China's green,low-carbon,and circulardevelopment economic system(theGLCCD Economic System)is being developed.By establishing the indicator system and indicators,the spatiotempor...This study aims to measure how well China's green,low-carbon,and circulardevelopment economic system(theGLCCD Economic System)is being developed.By establishing the indicator system and indicators,the spatiotemporal range entropy weight method,Gini coefficient,Theil index,convergence model,and national and provincial data from 2012 to 2017 are employed.The construction level of almost all GLCCD Economic Systems at national and provincial levels has shown improvement during the study period.Among them,a significant boost is only observed in the development power indicator;improvement in the production system indicator and development benefit indicatorismild,andthelifesystemindicator sees a decline year by year.The construction level of the GLCCD Economic System throughout China is generally balanced but tends to expand in scale.However,the inter-regional developmenttbenefit indicator showsaconvergence trend.Based on the analysis of the similarities and differences between greenandlow-carboncircular development,the development power and development benefit,production system,and life system are incorporated into a unified logical framework.The construction level of the GLCCD Economic System is measured as a whole in a holistic manner.This study finds out the scientific connotation oftheGLCCD Economic System.The changing trends and regional differences in the construction level of the GLCCD Economic System are revealed.These findings provide a clear and reliable decision-making basis for the construction of the GLCCD Economic System.展开更多
Introduction:This study is aimed at analyzing farmers’perception and adaptation to climate change in the Dabus watershed.It is based on analysis of data collected from 734 randomly selected farm household heads subst...Introduction:This study is aimed at analyzing farmers’perception and adaptation to climate change in the Dabus watershed.It is based on analysis of data collected from 734 randomly selected farm household heads substantiated with Focus Group Discussions and field observations.Methods:The study employed descriptive methods to assess farmers’perception of climate change,local indicators of climate change and types of adaptation measures exercised to cope up with the risk of the change in climate.The study also employed the Heckman sample selection model to analyze the two-step process of adaptation to climate change which initially requires farmers’perception that climate is changing prior to responding to the changes through adaptation measures.Results:Based on the model result educational attainment,the age of the head of the household,the number of crop failures in the past,changes in temperature and precipitation significantly influenced farmers’perception of climate change in wet lowland parts of the study area.In dry lowland condition,farming experience,climate information,duration of food shortage,and the number of crop failures experienced determined farmers’perception of climate change.Farmers’adaptation decision in both the wet and dry lowland conditions is influenced by household size,the gender of household head,cultivated land size,education,farm experience,non-farm income,income from livestock,climate information,extension advice,farm-home distance and number of parcels.However,the direction of influence and significance level of most of the explanatory variables vary between the two parts of the study area.Conclusions:In line with the results,any intervention that promotes the use of adaptation measures to climate change may account for location-specific factors that determine farmers'perception of climate change and adaptive responses thereof.展开更多
Soil erosion and deposition in a tropical mountainous river basin, viz., Pambar River Basin (PRB), in a rain shadow region of the southern Western Ghats (India) were modelled using Revised Universal Soil Loss Equation...Soil erosion and deposition in a tropical mountainous river basin, viz., Pambar River Basin (PRB), in a rain shadow region of the southern Western Ghats (India) were modelled using Revised Universal Soil Loss Equation (RUSLE) and transport limited sediment delivery (TLSD) function in GIS. Mean gross soil erosion in the basin is 11.70 t ha-1 yr-1, and is comparable with the results of previous soil erosion studies from the region. However, mean net soil erosion from the basin is 2.92 t ha-1 yr-1 only, which is roughly 25%of the gross soil erosion. Although natural vegetation belts show relatively higher gross- and net-soil erosion rates (mainly due to high LS and C factors), their sediment transport efficiency is remarkably less, compared to the land use/ land cover types with anthropogenic signatures (i.e., plantations and crop-lands). Despite the lesser amount of annual rainfall, the high rates of soil loss from the semi-arid areas of the basin might be the result of the poor protective vegetation cover as well as isolated high intensity rainfall events. The study highlights the significance of climate-specific plans for soil erosion manage-ment and conservation of the soil resources of the basins developed in rain shadow regions.展开更多
Background:Ethiopia is frequently cited as a country that is highly vulnerable to climate variability and change.The country’s high vulnerability arises mostly from climate-sensitive agricultural sector that suffers ...Background:Ethiopia is frequently cited as a country that is highly vulnerable to climate variability and change.The country’s high vulnerability arises mostly from climate-sensitive agricultural sector that suffers a lot from risks associated with rainfall variability.The vulnerability factors(exposure,sensitivity,and adaptive capacity)of the agricultural livelihoods to climate variability and change differ across agro-ecological systems(AESs).Therefore,the aim of this study was to analyze AES-specific vulnerability of smallholder farmers to climate variability and change in the Fincha’a sub-basin.We surveyed 380 respondents from 4 AESs(highland,midland,wetland,and lowland)randomly selected.Furthermore,focus group discussion and key informant interviews were also performed to supplement and substantiate the quantitative data.Livelihood vulnerability index was employed to analyze the levels of smallholders’agriculture vulnerability to climate variability and change.Data on socioeconomic and biophysical attribute were collected and combined into the indices and vulnerability score was calculated for each agro-ecological system.Results:Considerable variation was observed across the agro-ecological systems in profile,indicator,and the three livelihood vulnerability indices-Intergovernmental Panel on Climate Change dimensions(exposure,sensitivity,and adaptive capacity)of vulnerability.The lowland AES exhibited higher exposure,low adaptive capacity,and high vulnerability,while the midland AES demonstrated lower exposure,higher adaptive capacity,and lower vulnerability.The wetland and highland AESs scored intermediate results.Conclusion:Our results suggest that resilience-building adaptation strategies are vital to reduce the vulnerability of smallholder farmers.The measures taken should consider site-specific agro-ecological system requirements to reduce the vulnerability of smallholder mixed crop-livestock agriculture system.Since the approach based on the long-term realization of the community,any strategy designed based on such assessments is applicable to local condition.展开更多
Watershed management practices have been implemented to avert land degradation and to enhance people's livelihoods in the highlands of Ethiopia for several years.However,the successes of these practices have been ...Watershed management practices have been implemented to avert land degradation and to enhance people's livelihoods in the highlands of Ethiopia for several years.However,the successes of these practices have been quite limited and the main factors affecting these practices have not been examined in detail.This study intended to investigate rates and intensities of adoption of watershed management practices and to determine the main factors affecting farmers' adoption decisions in the upper Gibe basin.Data were collected from 304 household heads in six sub catchments across different topographic settings using household interview.Focus groups discussions,key informant interviews and transect walk observations were also used.Descriptive statistics and econometric models such as,multivariate and ordered probit were used to analyze the data.The results revealed that the majority of households (82.6 percent) used at least one of the six practices considered in this study.Soil bund,grass strip cultivation with soil bund and compost were the major watershed management practices adopted by farmers.Adoption rate and intensity of adoption were better for program participants and in upper and middle topographic settings.The results of the multivariate and ordered probit analysis indicated that household size,extension services,credit services,training services and perception of soil erosion had positive significant relationship with both rate and intensity of adoption of most practices.Hence,policy makers and planners need to consider labor,knowledge and awareness,and capital intensive nature of the practices for the up scaling planning and implementations of watershed intervention technologies.展开更多
The Clouds and the Earth's Radiant Energy System program,which uses the Moderate Resolution Imaging Spectroradiometer(CM),has been updated with the launch of new satellites and the availability of newly upgraded r...The Clouds and the Earth's Radiant Energy System program,which uses the Moderate Resolution Imaging Spectroradiometer(CM),has been updated with the launch of new satellites and the availability of newly upgraded radiation data.The spatial and temporal variability of daily averaged synoptic 1-degree CM version 3(CMv3)(old)and version 4(CMv4)(new)downwelling shortwave(QS)and longwave radiation(QL)data in the global tropical oceans spanning 30°S-30°N from 2000 to 2017 is investigated.Daily in situ data from the Global Tropical Moored Buoy Array were used to validate the CM data from 2000 to 2015.When compared to CMv3,both QS and QL in CMv4 show significant improvements in bias,root-mean-square error,and standard deviations.Furthermore,a long-term trend analysis shows that QS has been increasing by 1 W m^(−2) per year in the Southern Hemisphere.In contrast,the Northern Hemisphere has a−0.7 W m^(−2) annual decreasing trend.QS and QL exhibit similar spatial trend patterns.However,in the Indian Ocean,Indo-Pacific warm pool region,and Southern Hemisphere,QL spatial patterns in CMv3 and CMv4 differ with an opposite trend(0.5 W m^(−2)).These annual trends in QS and QL could cause the sea surface temperature to change by−0.2 to 0.3℃per year in the tropical oceans.These results stress the importance of accurate radiative flux data,and CMv4 can be an alternative to reanalysis or other model-simulated data.展开更多
基金Financial support from Kerala State Council for Science, Technology, and Environment (004/FSHP/05KSCSTE)
文摘Revised Universal Soil Loss Equation(RUSLE) model coupled with transport limited sediment delivery(TLSD) function was used to predict the longtime average annual soil loss, and to identify the critical erosion-/deposition-prone areas in a tropical mountain river basin, viz., Muthirapuzha River Basin(MRB; area=271.75 km^2), in the southern Western Ghats, India. Mean gross soil erosion in MRB is 14.36 t ha^(-1) yr^(-1), whereas mean net soil erosion(i.e., gross erosion-deposition) is only 3.60 t ha^(-1) yr^(-1)(i.e., roughly 25% of the gross erosion). Majority of the basin area(~86%) experiences only slight erosion(<5 t ha^(-1) yr^(-1)), and nearly 3% of the area functions as depositional environment for the eroded sediments(e.g., the terraces of stream reaches, the gentle plains as well as the foot slopes of the plateau scarps and the terrain with concordant summits). Although mean gross soil erosion rates in the natural vegetation belts are relatively higher, compared to agriculture, settlement/built-up areas and tea plantation, the sediment transport efficiency in agricultural areas and tea plantation is significantly high,reflecting the role of human activities on accelerated soil erosion. In MRB, on a mean basis, 0.42 t of soil organic carbon(SOC) content is being eroded per hectare annually, and SOC loss from the 4th order subbasins shows considerable differences, mainly due to the spatial variability in the gross soil erosion rates among the sub-basins. The quantitative results, on soil erosion and deposition, modelled using RUSLE and TLSD, are expected to be beneficial while formulating comprehensive land management strategies for reducing the extent of soil degradation in tropical mountain river basins.
文摘Climate change is impacting climate sensitive rural livelihood systems. Exposure, sensitivity, and adaptive capacity of agricultural livelihoods to climate variability and change differ across agro-ecologies and these pose a challenge to climate resilient development strategy. This study assesses agro-ecology specific vulnerability of smallholder farmers to climate change and variability in the Dabus Watershed (North-west Ethiopia), based on a survey of 734 farm households complemented with focus group discussion and key informant interviews. Recognizing the physiographic and climatic diversity that exists across agro-ecologies in the study area, Livelihood Vulnerability Index (LVI) framed within the United Nations Intergovernmental Panel on Climate Change (IPCC) vulnerability framework (LVI-IPCC) is adapted to assess agro-ecology specific vulnerability in two local agro-ecologies, namely wet lowland and dry lowland. For each agro-ecology, exposure, sensitivity and adaptive capacity indices as well as LVI-IPCC vulnerability score was calculated. The result shows that the dry lowland agro-ecology has a relatively higher exposure and sensitivity to climate stresses with a comparatively limited adaptive capability. On the other hand, the wet lowland agro-ecology exhibits intermediate vulnerability with a relatively lower perceived exposure and higher adaptive capacity. Higher exposure relative to adaptive capacity resulted in a positive LVI-IPCC score in the dry lowland agro-ecology and positioned it in more vulnerable level than the wet lowland. A higher adaptive capacity relative to exposure unveils a negative LVI-IPCC score for the wet lowland agro-ecology and positioned it in a moderate vulnerability category. In line with the findings, there is a need to set agro-ecology specific priorities for intervention that is most needed to cop up with the effects of climate variability and change in each agro-ecology. Climate risk exposure levels can be reduced through timely provision of climate specific information and early warning systems aimed at enhancing preparedness of farm households to extreme events. It is also crucial to expand availability of infrastructural facilities such as market, health services, and veterinary services so as to enhance adaptive capacity. Supporting alternative livelihood options and enhancing water harvesting practices for supplementary irrigation also call policy attention.
文摘The objective of this paper was to determine the factors that influence farmers＇ decision to use two categories of sustainable land management （SLM） practices as adaptation strategy to climate change in the North-West Ethiopia. It was based on analysis of data collected from 734 farm household heads and employed probit regression model to analyze the determinants of adaptation to climate change through SLM measures. Based on the model result, factors, like perception of climate change, exposure to adaptation techniques, education, perception of land degradation, slope, land prone to degradation, number of parcels, crop enterprise income, land size, farm distance, economically active family size and agro-ecology are found important in determining farmers＇ decision to use structural land management practices. Likewise, perception of climate change, exposure to adaptation, farming experience, slope, crop enterprise income, land prone to degradation and agro-ecology are found important in affecting farmers＇ decision to use non-structural land management practices as adaptation measure. Therefore, in line with the findings of the analysis, any intervention that promotes use of land management practices as adaptation strategy should take into account agro-ecology specific factors that are relevant to the nature of the land management practices. Moreover, since scaling up of SLM practices as adaptation strategy is resource intensive, it requires both public and non-public investment for providing technological support and raising awareness. Failure to do so would adversely affect crop productivity and exacerbate food insecurity problems at farm household level.
基金This work was supported by the National Natural Science Foundation of China(Grant No.70773068)。
文摘The establishment of the environmental management system in the financial sector can be effectively promoted through the introduction of the environmental protection concept and its implementation by the financial sector.The impact of a sustainable development system on the sector is analyzed in this article from three aspects:environmental risk assessment,financing support for environmental protection projects,and financial services to environmentally friendly corporations and individuals.Influential factors on the development of the environmental management system in China’s financial sector are discussed from the perspective of various entities such as financial institutions,financial regulation authorities,environmental protection departments,corporations,and the public.It is pointed out that China’s financial sector is now in the transitional phase from a defensive attitude to a preventive attitude.Strengthening governmental guidance,the supervision of regulators as well as public awareness of environmental protection should be used to enhance the initiative in the development of the environmental management system in the Chinese financial sector.
文摘Awareness of how soil properties vary over agroecosystems(AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study examined the characteristics of soil quality attributes and implications for agriculture in the Choke Mountain watershed in Ethiopia. Forty-seven composite soil samples(0–20 cm deep) were collected from lowland and valley fragmented(AES 1),midland plain with black soil(AES 2), midland plain with brown soil(AES 3),sloppy midland land(AES 4), and hilly and mountainous highlands(AES 5).Ten of 15 soil quality properties were significant(P < 0.05 or 0.01), including silt, exchangeable bases, cation exchange capacity, percent base saturation,p H, organic matter, total nitrogen and available phosphorous(P) across the five AES. However, all properties were variable with coefficients of variation from 7%(total porosity) to 169%(available P) across the AES. Although AES 2and 3 are affected by waterlogging and acidity, these two have better prospects for agriculture, but AES 1, 4, and 5 are unsuitable for agriculture because of soil erosion. Therefore, appropriate and applicable soil management strategies, particularly lime application and organic fertilizer, are fundamental to reversing soil acidity and improving soil fertility.
基金This paper is a phased research result of the National Natural Science Foundation of China(No.71873143)the key discipline construction program of the Summit Plan of the ChineseAcademyof Social Sciences.
文摘This study aims to measure how well China's green,low-carbon,and circulardevelopment economic system(theGLCCD Economic System)is being developed.By establishing the indicator system and indicators,the spatiotemporal range entropy weight method,Gini coefficient,Theil index,convergence model,and national and provincial data from 2012 to 2017 are employed.The construction level of almost all GLCCD Economic Systems at national and provincial levels has shown improvement during the study period.Among them,a significant boost is only observed in the development power indicator;improvement in the production system indicator and development benefit indicatorismild,andthelifesystemindicator sees a decline year by year.The construction level of the GLCCD Economic System throughout China is generally balanced but tends to expand in scale.However,the inter-regional developmenttbenefit indicator showsaconvergence trend.Based on the analysis of the similarities and differences between greenandlow-carboncircular development,the development power and development benefit,production system,and life system are incorporated into a unified logical framework.The construction level of the GLCCD Economic System is measured as a whole in a holistic manner.This study finds out the scientific connotation oftheGLCCD Economic System.The changing trends and regional differences in the construction level of the GLCCD Economic System are revealed.These findings provide a clear and reliable decision-making basis for the construction of the GLCCD Economic System.
基金The authors would like to thank Addis Ababa University(AAU)and Dire-Dawa University(DDU)for providing financial support for the data collection and write-up of the manuscript.
文摘Introduction:This study is aimed at analyzing farmers’perception and adaptation to climate change in the Dabus watershed.It is based on analysis of data collected from 734 randomly selected farm household heads substantiated with Focus Group Discussions and field observations.Methods:The study employed descriptive methods to assess farmers’perception of climate change,local indicators of climate change and types of adaptation measures exercised to cope up with the risk of the change in climate.The study also employed the Heckman sample selection model to analyze the two-step process of adaptation to climate change which initially requires farmers’perception that climate is changing prior to responding to the changes through adaptation measures.Results:Based on the model result educational attainment,the age of the head of the household,the number of crop failures in the past,changes in temperature and precipitation significantly influenced farmers’perception of climate change in wet lowland parts of the study area.In dry lowland condition,farming experience,climate information,duration of food shortage,and the number of crop failures experienced determined farmers’perception of climate change.Farmers’adaptation decision in both the wet and dry lowland conditions is influenced by household size,the gender of household head,cultivated land size,education,farm experience,non-farm income,income from livestock,climate information,extension advice,farm-home distance and number of parcels.However,the direction of influence and significance level of most of the explanatory variables vary between the two parts of the study area.Conclusions:In line with the results,any intervention that promotes the use of adaptation measures to climate change may account for location-specific factors that determine farmers'perception of climate change and adaptive responses thereof.
文摘Soil erosion and deposition in a tropical mountainous river basin, viz., Pambar River Basin (PRB), in a rain shadow region of the southern Western Ghats (India) were modelled using Revised Universal Soil Loss Equation (RUSLE) and transport limited sediment delivery (TLSD) function in GIS. Mean gross soil erosion in the basin is 11.70 t ha-1 yr-1, and is comparable with the results of previous soil erosion studies from the region. However, mean net soil erosion from the basin is 2.92 t ha-1 yr-1 only, which is roughly 25%of the gross soil erosion. Although natural vegetation belts show relatively higher gross- and net-soil erosion rates (mainly due to high LS and C factors), their sediment transport efficiency is remarkably less, compared to the land use/ land cover types with anthropogenic signatures (i.e., plantations and crop-lands). Despite the lesser amount of annual rainfall, the high rates of soil loss from the semi-arid areas of the basin might be the result of the poor protective vegetation cover as well as isolated high intensity rainfall events. The study highlights the significance of climate-specific plans for soil erosion manage-ment and conservation of the soil resources of the basins developed in rain shadow regions.
文摘Background:Ethiopia is frequently cited as a country that is highly vulnerable to climate variability and change.The country’s high vulnerability arises mostly from climate-sensitive agricultural sector that suffers a lot from risks associated with rainfall variability.The vulnerability factors(exposure,sensitivity,and adaptive capacity)of the agricultural livelihoods to climate variability and change differ across agro-ecological systems(AESs).Therefore,the aim of this study was to analyze AES-specific vulnerability of smallholder farmers to climate variability and change in the Fincha’a sub-basin.We surveyed 380 respondents from 4 AESs(highland,midland,wetland,and lowland)randomly selected.Furthermore,focus group discussion and key informant interviews were also performed to supplement and substantiate the quantitative data.Livelihood vulnerability index was employed to analyze the levels of smallholders’agriculture vulnerability to climate variability and change.Data on socioeconomic and biophysical attribute were collected and combined into the indices and vulnerability score was calculated for each agro-ecological system.Results:Considerable variation was observed across the agro-ecological systems in profile,indicator,and the three livelihood vulnerability indices-Intergovernmental Panel on Climate Change dimensions(exposure,sensitivity,and adaptive capacity)of vulnerability.The lowland AES exhibited higher exposure,low adaptive capacity,and high vulnerability,while the midland AES demonstrated lower exposure,higher adaptive capacity,and lower vulnerability.The wetland and highland AESs scored intermediate results.Conclusion:Our results suggest that resilience-building adaptation strategies are vital to reduce the vulnerability of smallholder farmers.The measures taken should consider site-specific agro-ecological system requirements to reduce the vulnerability of smallholder mixed crop-livestock agriculture system.Since the approach based on the long-term realization of the community,any strategy designed based on such assessments is applicable to local condition.
文摘Watershed management practices have been implemented to avert land degradation and to enhance people's livelihoods in the highlands of Ethiopia for several years.However,the successes of these practices have been quite limited and the main factors affecting these practices have not been examined in detail.This study intended to investigate rates and intensities of adoption of watershed management practices and to determine the main factors affecting farmers' adoption decisions in the upper Gibe basin.Data were collected from 304 household heads in six sub catchments across different topographic settings using household interview.Focus groups discussions,key informant interviews and transect walk observations were also used.Descriptive statistics and econometric models such as,multivariate and ordered probit were used to analyze the data.The results revealed that the majority of households (82.6 percent) used at least one of the six practices considered in this study.Soil bund,grass strip cultivation with soil bund and compost were the major watershed management practices adopted by farmers.Adoption rate and intensity of adoption were better for program participants and in upper and middle topographic settings.The results of the multivariate and ordered probit analysis indicated that household size,extension services,credit services,training services and perception of soil erosion had positive significant relationship with both rate and intensity of adoption of most practices.Hence,policy makers and planners need to consider labor,knowledge and awareness,and capital intensive nature of the practices for the up scaling planning and implementations of watershed intervention technologies.
基金We acknowledge the Department of Earth Sciences,Uppsala University,and the Swedish Research Council(VR)nr 2017-03988 for supporting this study.
文摘The Clouds and the Earth's Radiant Energy System program,which uses the Moderate Resolution Imaging Spectroradiometer(CM),has been updated with the launch of new satellites and the availability of newly upgraded radiation data.The spatial and temporal variability of daily averaged synoptic 1-degree CM version 3(CMv3)(old)and version 4(CMv4)(new)downwelling shortwave(QS)and longwave radiation(QL)data in the global tropical oceans spanning 30°S-30°N from 2000 to 2017 is investigated.Daily in situ data from the Global Tropical Moored Buoy Array were used to validate the CM data from 2000 to 2015.When compared to CMv3,both QS and QL in CMv4 show significant improvements in bias,root-mean-square error,and standard deviations.Furthermore,a long-term trend analysis shows that QS has been increasing by 1 W m^(−2) per year in the Southern Hemisphere.In contrast,the Northern Hemisphere has a−0.7 W m^(−2) annual decreasing trend.QS and QL exhibit similar spatial trend patterns.However,in the Indian Ocean,Indo-Pacific warm pool region,and Southern Hemisphere,QL spatial patterns in CMv3 and CMv4 differ with an opposite trend(0.5 W m^(−2)).These annual trends in QS and QL could cause the sea surface temperature to change by−0.2 to 0.3℃per year in the tropical oceans.These results stress the importance of accurate radiative flux data,and CMv4 can be an alternative to reanalysis or other model-simulated data.
