The Dajiu Lake is an important subtropical alpine wetland in central China.In May of 2019,an ecological investigation was conducted on water quality and aquatic organisms(phytoplankton,zooplankton and zoobenthos)of th...The Dajiu Lake is an important subtropical alpine wetland in central China.In May of 2019,an ecological investigation was conducted on water quality and aquatic organisms(phytoplankton,zooplankton and zoobenthos)of the Dajiu Lake in Shennongjia forest region.The results showed that parameters of water quality in No.5 and No.9 sub lakes of the Dajiu Lake corresponded with standard of class II water of the Environmental Quality Standards for Surface Water(GB 3838-2002),while other sub lakes corresponded with standard of class III water.Diversity indexes of phytoplankton and zooplankton ranged from 2.0 to 3.0,and there were two families(Chironomidae and Libellulidae Rambur)of one phylum(Arthropoda)in zoobenthos.Comprehensive health index of entropy weight was used to evaluate water ecological status of the Dajiu Lake,and water quality of No.5,No.8 and No.9 sub lakes was in a healthy status,while other sub lakes were in sub-health status.Finally,corresponding countermeasures were proposed according to protection needs of the Dajiu Lake.展开更多
This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCC...This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCCI in China 1949-2013 are analyzed using empirical mode decomposition(EMD). Nonlinear models of per capita EFCI and BCCI in China 1949-2013 are presented and their cycles and predictions from 2014 to 2023 are analyzed. The results over the last 65 years show:(1) EFCI in China has increased constantly with fluctuations, while BCCI has slowly decreased. Their annual change rates are 2.81% and-1.26%, respectively. The increasing EFCI indicates a gradual improvement in China's sustainable development potential; the decreasing BCCI indicates severe environmental and population challenges.(2) The cycles of per capita EFCI have periods of 5.4 and 16.3 years, while cycles of per capita BCCI have periods of 3.6, 13,and 21.7 years. The predictive models indicate that EFCI will first decrease, reaching 0.02725 in2014, and will subsequently increase to 0.03261 in 2021. BCCI will increase, reaching 0.01365 in2014 and 0.01541 in 2022. EFCI and BCCI will reach 0.03037 and 0.01537, respectively, in 2023.Policymakers should ensure that the EFCI and BCCI increase in 2023.展开更多
Globally,shallow aquifer groundwater(GW)has been severely affected in recent decades for both geogenic and anthropogenic reasons.The hydro-geochemical characteristics of the GW change inconsistently with the addition ...Globally,shallow aquifer groundwater(GW)has been severely affected in recent decades for both geogenic and anthropogenic reasons.The hydro-geochemical characteristics of the GW change inconsistently with the addition of unwanted inorganic trace elements into the GW aquifer of the Indo-Bangladesh delta region(IBDR),such as arsenic(As)along with fluoride(F-)contamination.Contaminated GW can have a negative impact on drinking water supplies and agricultural output.GW pollution can have serious adverse effects on the environment and human health.Thus,the GW quality of this region is deteriorating progressively,and human health threatening by various life-threatening disorders.Hence,the current study concentrated on the GW quality evaluation and prediction of possible health issues in the IBDR due to elevated contamination of As along with F-within GW aquifers by considering sixteen causative.Field survey-based statistical methods such as entropy quality index(EWQI)combined with health risk index(HRI)was implemented for evaluating the As and F-sensitivity with the help of correlation testing and principal component analysis.The study's outcome explains that a substantial portion of the IBDR has been vastly experiencing inferior GW quality,environmental issues,and health-related problems in dry and wet seasons,correspondingly for As and F-exposure.Piper diagram verified the suitability of water that almost 55%of GW across the study area’s aquifers are unfit for drinking as well as cultivation of crops.Sensitivity analysis and the Monte Carlo simulation method were also applied to assess the contaminant's concentration level and probable health risk appraisal.The present study concludes that the elevated exposure of As and F-pollution has to be monitored regularly and prevent unwanted GW contamination through implementing sustainable approaches and policies to fulfil the sustainable development goal 6(SDG-6)till 2030,ensuring the most basic human right of clean,safe,and hygienic water.展开更多
Rapid conversion of conserved land and cropland to non-agricultural purposes is threatening the ecological areas and dominant agricultural activities that are the main sources of livelihood in urban fringe areas of Ad...Rapid conversion of conserved land and cropland to non-agricultural purposes is threatening the ecological areas and dominant agricultural activities that are the main sources of livelihood in urban fringe areas of Addis Ababa City.The combinations of government policy,socioeconomic,demographic dynamics,and biophysical triggers have driven such transformation.However,the recent fast urban expansion and infrastructural development could have accelerated the severity and rate at which urban growth impacts the ecosystem and fertile agricultural land.Yet,little attention is given about their impacts on forest and farming communities in the western fringe areas of Addis Ababa during the recent past.This study,therefore,aimed at quantifying and analyzing the trends of the urban growth and its impacts on flora and agricultural land in Sebeta-Awas town using an integrated GIS tool,remote sensing technique,and Shannon entropy method.Landsat TM of 1986,ETM+of 2002,and OLI of 2019 were used to produce land use/land cover(LULC)classes.Object-based classification technique was carried out to generate the LULC and to measure the changes in the urban land-use class within the satellite town in the year 1986,2002,and 2019.Shannon entropy method was applied to model study area’s urban sprawl,growth trend,and spatial change.Over the past three decades(1986-2019),Sebeta-Awas town has experienced severe urban sprawl following lack of proper development control and management.The annual urban growth rates of 1.2,5.5,and~15%for the periods of 1986,2002,and 2019,respectively were obtained mainly at the expenses of agricultural land(25.48%)and forest land(16.6%),catalyzed urban sprawl which finally led to serious deforestation and reduction in rural farmland.The findings indicate that the average of entropy index increased from 0.02 in the year 1986 to 0.996 in the year 2019,indicating more dispersed urban growth to the outskirts,and spatially indicating anticlockwise shifting.In this regard,more than 90.2%of forest loss due to agricultural encroachment,built-up area expansion,and construction was widely observed in Sebeta and Alem Gena areas,of course,Northeast zone in this study.It is concluded that deforestation and continual evacuation of farming communities in the urban fringe areas due to rapid urban expansion in the name of investment and infrastructural development is expected to be worsened in the near future unless strong policy revision and management actions are undertaken.展开更多
Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are re...Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species.The present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss Alps.Methods Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss Alps.Important Findings Our study highlights two main points.First,climate and land-use factors play an important role in mountain plant community turnover.Second,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community assembly.Overall,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.展开更多
Using the 2007 input-output data and 2012 household survey data,this paper estimated the overall VAT and business tax burden of urban households in China on basis of the statutory tax rates,and then studied the redist...Using the 2007 input-output data and 2012 household survey data,this paper estimated the overall VAT and business tax burden of urban households in China on basis of the statutory tax rates,and then studied the redistribution effects of China’s recent VAT enlargement reform.We found that this reform improved the redistribution effects of VAT and business tax mainly through lowering the average tax burden and reducing the inequality within the bottom-income group,but the inequality among different income groups was not reduced considerably.Based on a simulation analysis,we finally suggested the reduction of applicable rates on necessities to improve the redistribution effects of VAT more effectively.展开更多
基金Supported by Key Scientific Research Project of Hubei Department of Water Resources in 2017(HBSLKY201719).
文摘The Dajiu Lake is an important subtropical alpine wetland in central China.In May of 2019,an ecological investigation was conducted on water quality and aquatic organisms(phytoplankton,zooplankton and zoobenthos)of the Dajiu Lake in Shennongjia forest region.The results showed that parameters of water quality in No.5 and No.9 sub lakes of the Dajiu Lake corresponded with standard of class II water of the Environmental Quality Standards for Surface Water(GB 3838-2002),while other sub lakes corresponded with standard of class III water.Diversity indexes of phytoplankton and zooplankton ranged from 2.0 to 3.0,and there were two families(Chironomidae and Libellulidae Rambur)of one phylum(Arthropoda)in zoobenthos.Comprehensive health index of entropy weight was used to evaluate water ecological status of the Dajiu Lake,and water quality of No.5,No.8 and No.9 sub lakes was in a healthy status,while other sub lakes were in sub-health status.Finally,corresponding countermeasures were proposed according to protection needs of the Dajiu Lake.
基金supported by the Opening Foundation of Jiangsu Key Laboratory of Environment Change&Ecological ConstructionNational Natural Science Foundation of China:[Grant Number 41372182]Research Center of Resource-exhausted Cities Transformation and Development:[Grant Number Kf2013y08]
文摘This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCCI in China 1949-2013 are analyzed using empirical mode decomposition(EMD). Nonlinear models of per capita EFCI and BCCI in China 1949-2013 are presented and their cycles and predictions from 2014 to 2023 are analyzed. The results over the last 65 years show:(1) EFCI in China has increased constantly with fluctuations, while BCCI has slowly decreased. Their annual change rates are 2.81% and-1.26%, respectively. The increasing EFCI indicates a gradual improvement in China's sustainable development potential; the decreasing BCCI indicates severe environmental and population challenges.(2) The cycles of per capita EFCI have periods of 5.4 and 16.3 years, while cycles of per capita BCCI have periods of 3.6, 13,and 21.7 years. The predictive models indicate that EFCI will first decrease, reaching 0.02725 in2014, and will subsequently increase to 0.03261 in 2021. BCCI will increase, reaching 0.01365 in2014 and 0.01541 in 2022. EFCI and BCCI will reach 0.03037 and 0.01537, respectively, in 2023.Policymakers should ensure that the EFCI and BCCI increase in 2023.
文摘Globally,shallow aquifer groundwater(GW)has been severely affected in recent decades for both geogenic and anthropogenic reasons.The hydro-geochemical characteristics of the GW change inconsistently with the addition of unwanted inorganic trace elements into the GW aquifer of the Indo-Bangladesh delta region(IBDR),such as arsenic(As)along with fluoride(F-)contamination.Contaminated GW can have a negative impact on drinking water supplies and agricultural output.GW pollution can have serious adverse effects on the environment and human health.Thus,the GW quality of this region is deteriorating progressively,and human health threatening by various life-threatening disorders.Hence,the current study concentrated on the GW quality evaluation and prediction of possible health issues in the IBDR due to elevated contamination of As along with F-within GW aquifers by considering sixteen causative.Field survey-based statistical methods such as entropy quality index(EWQI)combined with health risk index(HRI)was implemented for evaluating the As and F-sensitivity with the help of correlation testing and principal component analysis.The study's outcome explains that a substantial portion of the IBDR has been vastly experiencing inferior GW quality,environmental issues,and health-related problems in dry and wet seasons,correspondingly for As and F-exposure.Piper diagram verified the suitability of water that almost 55%of GW across the study area’s aquifers are unfit for drinking as well as cultivation of crops.Sensitivity analysis and the Monte Carlo simulation method were also applied to assess the contaminant's concentration level and probable health risk appraisal.The present study concludes that the elevated exposure of As and F-pollution has to be monitored regularly and prevent unwanted GW contamination through implementing sustainable approaches and policies to fulfil the sustainable development goal 6(SDG-6)till 2030,ensuring the most basic human right of clean,safe,and hygienic water.
文摘Rapid conversion of conserved land and cropland to non-agricultural purposes is threatening the ecological areas and dominant agricultural activities that are the main sources of livelihood in urban fringe areas of Addis Ababa City.The combinations of government policy,socioeconomic,demographic dynamics,and biophysical triggers have driven such transformation.However,the recent fast urban expansion and infrastructural development could have accelerated the severity and rate at which urban growth impacts the ecosystem and fertile agricultural land.Yet,little attention is given about their impacts on forest and farming communities in the western fringe areas of Addis Ababa during the recent past.This study,therefore,aimed at quantifying and analyzing the trends of the urban growth and its impacts on flora and agricultural land in Sebeta-Awas town using an integrated GIS tool,remote sensing technique,and Shannon entropy method.Landsat TM of 1986,ETM+of 2002,and OLI of 2019 were used to produce land use/land cover(LULC)classes.Object-based classification technique was carried out to generate the LULC and to measure the changes in the urban land-use class within the satellite town in the year 1986,2002,and 2019.Shannon entropy method was applied to model study area’s urban sprawl,growth trend,and spatial change.Over the past three decades(1986-2019),Sebeta-Awas town has experienced severe urban sprawl following lack of proper development control and management.The annual urban growth rates of 1.2,5.5,and~15%for the periods of 1986,2002,and 2019,respectively were obtained mainly at the expenses of agricultural land(25.48%)and forest land(16.6%),catalyzed urban sprawl which finally led to serious deforestation and reduction in rural farmland.The findings indicate that the average of entropy index increased from 0.02 in the year 1986 to 0.996 in the year 2019,indicating more dispersed urban growth to the outskirts,and spatially indicating anticlockwise shifting.In this regard,more than 90.2%of forest loss due to agricultural encroachment,built-up area expansion,and construction was widely observed in Sebeta and Alem Gena areas,of course,Northeast zone in this study.It is concluded that deforestation and continual evacuation of farming communities in the urban fringe areas due to rapid urban expansion in the name of investment and infrastructural development is expected to be worsened in the near future unless strong policy revision and management actions are undertaken.
基金Fellowship grant from the Faculty of Biology and Medicine University of Lausanne,Switzerland.
文摘Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species.The present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss Alps.Methods Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss Alps.Important Findings Our study highlights two main points.First,climate and land-use factors play an important role in mountain plant community turnover.Second,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community assembly.Overall,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.
文摘Using the 2007 input-output data and 2012 household survey data,this paper estimated the overall VAT and business tax burden of urban households in China on basis of the statutory tax rates,and then studied the redistribution effects of China’s recent VAT enlargement reform.We found that this reform improved the redistribution effects of VAT and business tax mainly through lowering the average tax burden and reducing the inequality within the bottom-income group,but the inequality among different income groups was not reduced considerably.Based on a simulation analysis,we finally suggested the reduction of applicable rates on necessities to improve the redistribution effects of VAT more effectively.
