The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collect...The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006.Results showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of coliforms.Seasonally,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season.Spatially,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote areas.Correlation analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in water.Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.展开更多
The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such ...The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such as debris flows, often impact forest stands where they cause damage to individual trees, thereby generating growth disturbances(GD) in the tree-ring records. The identification and dating of GD enables reconstruction of the age of trees colonizing bare surfaces after major events, but also allows the assessment of the frequency or spatial distribution of past geomorphic process activity. Here we used increment cores from 65 Pinus leiophylla, Abies religiosa, and Alnus jorullensis trees growing in the Axal gorge, on the southern slopes of La Malinche volcano, to unravel past debris-flow activity both temporally and spatially. Based on the combination of GD records, a weighted tree response index(Wit), field evidence and hydrometeorological records, we reconstructed 23 debris flows since 1933.Interestingly, almost two-thirds of the reconstructed years with debris-flow activity in Axal gorge match with events recorded in Axaltzintle gorge located on the NE slopes of La Malinche. These findings suggest a regional triggering mechanism, most likely related to the occurrence of hurricanes. This research could be useful for disaster risk management of the La Malinche National Park.展开更多
There is growing interest in the correlation between working time and environmental pressures,but prior empirical studies mostly focused on static methodologies.This article used dynamic panel regression approaches to...There is growing interest in the correlation between working time and environmental pressures,but prior empirical studies mostly focused on static methodologies.This article used dynamic panel regression approaches to examine and compare the relationship among western,southern,and northern European countries over the period 1970-2010,and proved the existence of strongly significant relationships in all models.Furthermore,this article detected the relationship between working hours and environmental indicators(carbon emission and energy use) at different phases.We contribute to a further understanding of the environmental effects of the working time reduction policy by comparing the differences among various periods and country groups in a system generalized method of moments(GMM) dynamic framework.展开更多
A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cu...A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cultivation. Furthermore, no oxalic acid, tartaric acid, malic acid or citric acid, all possible factors in acidification, was detected in the nutrient solution of a growing plant. A proton pump inhibitor suppressed the acidification of the solution. Soil acidification might have been accelerated with a proton released from ammoniacal nitrogen preferentially for the growth, suggesting the specific mechanism of tea plant as a functional food.展开更多
In accordance with a revision of the Containers and Packaging Recycling Law, there is an accelerating trend towards charging for plastic shopping bags （PSBs） in Japan for the purpose of reducing their discharge. The...In accordance with a revision of the Containers and Packaging Recycling Law, there is an accelerating trend towards charging for plastic shopping bags （PSBs） in Japan for the purpose of reducing their discharge. The objectives of this research were to gauge, by means of a questionnaire survey, the opinions of retailers with regard to charging for PSBs, and to consider future directions for reducing the quantity of waste discharged. A questionnaire survey on charging for PSBs was conducted for retail stores in Shizuoka City. The survey was carried out in two phases. The results of the first phase （August to October 2008） showed that supermarkets were generally positive, while conversely other retailer types were negative. The results of the second phase （November to December, 2010）, targeting only supermarkets that had introduced charging after the first survey, showed that there was no major confusion and the shift proceeded relatively smoothly. In addition, the number of customers did not decline on account of charging, and the ratio of shoppers bringing their own reusable ＂eco bags＂ jumped dramatically. On these accounts, it is evident that charging for PSBs is an effective means of reducing usage of PSBs. The authors view it as important for the relevant governmental agencies to work towards promoting charging at retailers and simultaneously repeatedly explaining to consumers the necessity for charging.展开更多
In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a s...In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a small facility. However, a large facility which can run continuously at high temperature with stability would be preferable if the dioxin generation mechanism is to be considered. Accordingly, municipalities in contiguous areas should cooperate mutually by using a large facility. To evaluate the effect of the concentration of large facilities, the authors created a GIS （Geographic Information System） based database of combustible waste generation at town level in Shizuoka Prefecture. Focusing on large facilities in Shizuoka City and superannuated facilities in Shida area, the authors evaluated the effect of the concentration of large facilities in Shizuoka city on utilization rate of facilities, energy balance and CO2 emissions. Our results showed the amount of light oil consumption and CO2 emissions increased because the mileage distance of garbage collection trucks becomes longer. However, the utilization rates of facilities and the amount of energy recovery from waste are improved. From these standpoints, the authors conclude that the concentration of large facilities is better compared to a single municipality based facility.展开更多
National-level climate action plans are often formulated broadly. Spatially disaggregating these plans to individual municipalities can offer substantial benefits, such as enabling regional climate action strategies a...National-level climate action plans are often formulated broadly. Spatially disaggregating these plans to individual municipalities can offer substantial benefits, such as enabling regional climate action strategies and for assessing the feasibility of national objectives. Numerous spatial disaggregation approaches can be found in the literature. This study reviews and categorizes these. The review is followed by a discussion of the relevant methods for the disaggregation of climate action plans. It is seen that methods employing proxy data, machine learning models, and geostatistical ones are the most relevant methods for the spatial disaggregation of national energy and climate plans. The analysis offers guidance for selecting appropriate methods based on factors such as data availability at the municipal level and the presence of spatial autocorrelation in the data.As the urgency of addressing climate change escalates, understanding the spatial aspects of national energy and climate strategies becomes increasingly important. This review will serve as a valuable guide for researchers and practitioners applying spatial disaggregation in this crucial field.展开更多
The transitional path towards a highly renewable power system based on wind and solar energy sources is investigated considering their intermittent and spatially distributed characteristics. Using an extensive weather...The transitional path towards a highly renewable power system based on wind and solar energy sources is investigated considering their intermittent and spatially distributed characteristics. Using an extensive weather-driven simulation of hourly power mismatches between generation and load, we explore the interplay between geographical resource complementarity and energy storage strategies. Solar and wind resources are considered at variable spatial scales across Europe and related to the Swiss load curve, which serve as a typical demand side reference. The optimal spatial distribution of renewable units is further assessed through a parameterized optimization method based on a genetic algorithm. It allows us to explore systematically the effective potential of combined integration strategies depending on the sizing of the system, with a focus on how overall performance is affected by the definition of network boundaries. Upper bounds on integration schemes are provided considering both renewable penetration and needed reserve power capacity. The quantitative trade-off between grid extension, storage and optimal wind-solar mix is highlighted.This paper also brings insights on how optimal geographical distribution of renewable units evolves as a function of renewable penetration and grid extent.展开更多
Spatial and temporal distribution of octylphenol （OP） and nonylphenol （NP） in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from ...Spatial and temporal distribution of octylphenol （OP） and nonylphenol （NP） in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from 11 sites during the period of September- December 2004. Concentrations of OP and NP ranged from 11.3 to 348 ng/L and from 29 to 2591 ng/L, respectively. The high levels of NP and OP were found in November and December than in September and October. The levels of OP and NP have no significant spatial differences except September. Total organic matter in the sediments appeared to be an important factor in controlling the fate of these compounds in the aquatic environment.展开更多
In order to understand the mechanisms on the variation between rice cultivars in Cd uptake and accumulation, two pot soil experiments were conducted with typical rice cultivars that varied greatly in soil Cd uptake. T...In order to understand the mechanisms on the variation between rice cultivars in Cd uptake and accumulation, two pot soil experiments were conducted with typical rice cultivars that varied greatly in soil Cd uptake. The experiments with six rice cultivars showed that the root oxidation abilities of rice differed with rice cultivars and also with types of the cultivars, the cultivars with indica consanguinity were significantly higher than the cultivars with japonica consanguinity. Root oxidation abilities of the rice cultivars correlated positively and significantly （P〈0.01） with their Cd concentrations and Cd quantity accumulations in rice plants. The experiments with two rice cultivars showed that significant differences also existed between the two cultivars in pot soil redox potentials, which of Shan you 63 （higher soil Cd accumulator） were significantly higher than that of Wu yun jing 7 （lower soil Cd accumulator） under different soil Cd levels, but the degrees of the differences varied with soil Cd levels. The differences were larger under soil Cd treatments than the control. The results indicate that root oxidation ability, especially in Cd contaminated soil, is one of the main mechanisms which dominate Cd uptake and accumulation by rice plant.展开更多
The purpose of this paper was to assess the impact of urbanization on the groundwater level(GWL)in aquifers of Binh Duong(BD)Province.The research method is to analyze the trend of GWL,the recharge capacity of surface...The purpose of this paper was to assess the impact of urbanization on the groundwater level(GWL)in aquifers of Binh Duong(BD)Province.The research method is to analyze the trend of GWL,the recharge capacity of surface over time and the relationship between them.The data of the GWL used in the study are the average values in the dry and rainy seasons of 35 observation wells from 2011 to 2018,which are in Pleistocene and Pliocene aquifers.The ability to recharge groundwater from the surface in this study was represented by the curve number(CN),a parameter used in hydrology for calculating direct runoff or infiltration from rainfall.The land use data to identify the CN was analyzed from the Landsat images.The results show that besides over-exploitation,the change of surface characteristic due to the urbanization development process is also the cause of the GWL decline.The analysis of seasonal GWL data shows that the increase in impervious surface area is the cause of GWL decline in the Pleistocene aquifer,which is more evident in the rainy season than in the dry season.The statistical results also show that in the rainy season and in shallow aquifers,a higher CN change can be found with the wells that had a remarkable GWL decline compared to the remaining wells.展开更多
This paper presents the results of an experimental study on the influences of floodplain impermeable groynes on flow structure, velocity, and water depth around the groyne（s）. A wooden symmetrical compound channel w...This paper presents the results of an experimental study on the influences of floodplain impermeable groynes on flow structure, velocity, and water depth around the groyne（s）. A wooden symmetrical compound channel was used. Groyne models with three different groyne relative lengths, 0.5, 0.75, and 1.0, were used on one floodplain with single and series arrangements. Analysis of the experimental results using the measured flow velocity and water depth values showed that flow structure, velocity, and water depth mainly depend on groyne relative length and the relative distance between series groynes. The flow velocity at the main channel centerline increased by about 40%, 60%, and 85%, and in other parts on the horizontal plane at the floodplain mid-water, depth by about 75%, 125%, and 175% of its original value in eases of one-side floodplain groyne（s） with relative lengths of 0.5, 0.75, and 1.0, respectively. The effective distance between two groynes in series arrangement ranges from 3 to 4 times the groyne length. Using an impermeable groyne with a large relative length in river floodplains increases the generation of eddy and roller zones downstream of the groyne, leading to more scouring and deposition. To avoid that, the groyne relative length must be kept below half the floodplain width,展开更多
We have arrived at a critical juncture when it comes to understanding the numerous ways in which trade interacts with climate change and energy(trade-climate-energy nexus).Trade remains crucial for the sustainable dev...We have arrived at a critical juncture when it comes to understanding the numerous ways in which trade interacts with climate change and energy(trade-climate-energy nexus).Trade remains crucial for the sustainable development of the world's greatest trading nation:China.After clarifying the linkages within the trade,climate change and energy nexus,this article delves into China's specific needs and interests related to trade,climate change and energy.Then it explores the ways in which trade can contribute to China's needs,to sustainable energy development and to the goals of the global climate agreement that is under negotiation.One main findings are China is a key participant in negotiations on trade liberalization of environmental technologies and services.These negotiations are in China's interests in terms of innovative industries,technological upgrading,employment and public health.China could stand up for the interests of other emerging and developing countries and serve as an example in terms of transitioning to a low-carbon economy.Beyond trade barriers issues of domestic(energy)regulation such as fossil-fuel subsidies as well as investment,competition-policy,tradefacilitation and transit issues related to clean energy need to be addressed.Building trust between relevant actors across sectors and national borders will be of the essence in order to foster long-term cooperation on technological innovation.As a way forward,different approaches towards the governance of trade and climate change will be highlighted.Besides discussing the specific aspects of Chinese participation in global trade and climate change governance,this paper aims at offering broader insights into the nexus between trade,energy and climate governance in China.展开更多
Neurotoxicity induced by stress,radiation,chemicals,or metabolic diseases,is commonly associated with excitotoxicity,oxidative stress,and neuroinflammation.The pathological process of neurotoxicity induces neuronal de...Neurotoxicity induced by stress,radiation,chemicals,or metabolic diseases,is commonly associated with excitotoxicity,oxidative stress,and neuroinflammation.The pathological process of neurotoxicity induces neuronal death,interrupts synaptic plasticity in the brain,and is similar to that of diverse neurodegenerative diseases.Animal models of neurotoxicity have revealed that clinical symptoms and brain lesions can recover over time via neuroregenerative processes.Specifically,brain-derived neurotropic factor（BDNF） and gamma-aminobutyric acid（GABA）-ergic transmission are related to both neurodegeneration and neuroregeneration.This review summarizes the accumulating evidences that suggest a pathogenic role of BDNF and GABAergic transmission,their underlying mechanisms,and the relationship between BDNF and GABA in neurodegeneration and neuroregeneration.This review will provide a comprehensive overview of the underlying mechanisms of neuroregeneration that may help in developing potential strategies for pharmacotherapeutic approaches to treat neurotoxicity and neurodegenerative disease.展开更多
基金supported by the Scientific Research Foundation for the Doctor of Zhejiang Normal University (No. ZC304009166)
文摘The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006.Results showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of coliforms.Seasonally,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season.Spatially,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote areas.Correlation analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in water.Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.
文摘The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such as debris flows, often impact forest stands where they cause damage to individual trees, thereby generating growth disturbances(GD) in the tree-ring records. The identification and dating of GD enables reconstruction of the age of trees colonizing bare surfaces after major events, but also allows the assessment of the frequency or spatial distribution of past geomorphic process activity. Here we used increment cores from 65 Pinus leiophylla, Abies religiosa, and Alnus jorullensis trees growing in the Axal gorge, on the southern slopes of La Malinche volcano, to unravel past debris-flow activity both temporally and spatially. Based on the combination of GD records, a weighted tree response index(Wit), field evidence and hydrometeorological records, we reconstructed 23 debris flows since 1933.Interestingly, almost two-thirds of the reconstructed years with debris-flow activity in Axal gorge match with events recorded in Axaltzintle gorge located on the NE slopes of La Malinche. These findings suggest a regional triggering mechanism, most likely related to the occurrence of hurricanes. This research could be useful for disaster risk management of the La Malinche National Park.
基金supported by the State Scholarship Fund under the China Scholarship Council[grant number 201306240017]
文摘There is growing interest in the correlation between working time and environmental pressures,but prior empirical studies mostly focused on static methodologies.This article used dynamic panel regression approaches to examine and compare the relationship among western,southern,and northern European countries over the period 1970-2010,and proved the existence of strongly significant relationships in all models.Furthermore,this article detected the relationship between working hours and environmental indicators(carbon emission and energy use) at different phases.We contribute to a further understanding of the environmental effects of the working time reduction policy by comparing the differences among various periods and country groups in a system generalized method of moments(GMM) dynamic framework.
文摘A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cultivation. Furthermore, no oxalic acid, tartaric acid, malic acid or citric acid, all possible factors in acidification, was detected in the nutrient solution of a growing plant. A proton pump inhibitor suppressed the acidification of the solution. Soil acidification might have been accelerated with a proton released from ammoniacal nitrogen preferentially for the growth, suggesting the specific mechanism of tea plant as a functional food.
文摘In accordance with a revision of the Containers and Packaging Recycling Law, there is an accelerating trend towards charging for plastic shopping bags （PSBs） in Japan for the purpose of reducing their discharge. The objectives of this research were to gauge, by means of a questionnaire survey, the opinions of retailers with regard to charging for PSBs, and to consider future directions for reducing the quantity of waste discharged. A questionnaire survey on charging for PSBs was conducted for retail stores in Shizuoka City. The survey was carried out in two phases. The results of the first phase （August to October 2008） showed that supermarkets were generally positive, while conversely other retailer types were negative. The results of the second phase （November to December, 2010）, targeting only supermarkets that had introduced charging after the first survey, showed that there was no major confusion and the shift proceeded relatively smoothly. In addition, the number of customers did not decline on account of charging, and the ratio of shoppers bringing their own reusable ＂eco bags＂ jumped dramatically. On these accounts, it is evident that charging for PSBs is an effective means of reducing usage of PSBs. The authors view it as important for the relevant governmental agencies to work towards promoting charging at retailers and simultaneously repeatedly explaining to consumers the necessity for charging.
文摘In Japan, each municipality generally has its own municipal solid waste incineration facilities because of the principle of self-management in the respective territories. Typically, a small municipality often owns a small facility. However, a large facility which can run continuously at high temperature with stability would be preferable if the dioxin generation mechanism is to be considered. Accordingly, municipalities in contiguous areas should cooperate mutually by using a large facility. To evaluate the effect of the concentration of large facilities, the authors created a GIS （Geographic Information System） based database of combustible waste generation at town level in Shizuoka Prefecture. Focusing on large facilities in Shizuoka City and superannuated facilities in Shida area, the authors evaluated the effect of the concentration of large facilities in Shizuoka city on utilization rate of facilities, energy balance and CO2 emissions. Our results showed the amount of light oil consumption and CO2 emissions increased because the mileage distance of garbage collection trucks becomes longer. However, the utilization rates of facilities and the amount of energy recovery from waste are improved. From these standpoints, the authors conclude that the concentration of large facilities is better compared to a single municipality based facility.
基金funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No.101036458.
文摘National-level climate action plans are often formulated broadly. Spatially disaggregating these plans to individual municipalities can offer substantial benefits, such as enabling regional climate action strategies and for assessing the feasibility of national objectives. Numerous spatial disaggregation approaches can be found in the literature. This study reviews and categorizes these. The review is followed by a discussion of the relevant methods for the disaggregation of climate action plans. It is seen that methods employing proxy data, machine learning models, and geostatistical ones are the most relevant methods for the spatial disaggregation of national energy and climate plans. The analysis offers guidance for selecting appropriate methods based on factors such as data availability at the municipal level and the presence of spatial autocorrelation in the data.As the urgency of addressing climate change escalates, understanding the spatial aspects of national energy and climate strategies becomes increasingly important. This review will serve as a valuable guide for researchers and practitioners applying spatial disaggregation in this crucial field.
基金国家重点基础发展规划项目 [G1 9990 436 0 1 ( 973) ] WaterEnvironment and Food Security :Integrating Economic and EnvironmentalObjective-ACase Study of the Haihe River Basin in China资助
文摘The transitional path towards a highly renewable power system based on wind and solar energy sources is investigated considering their intermittent and spatially distributed characteristics. Using an extensive weather-driven simulation of hourly power mismatches between generation and load, we explore the interplay between geographical resource complementarity and energy storage strategies. Solar and wind resources are considered at variable spatial scales across Europe and related to the Swiss load curve, which serve as a typical demand side reference. The optimal spatial distribution of renewable units is further assessed through a parameterized optimization method based on a genetic algorithm. It allows us to explore systematically the effective potential of combined integration strategies depending on the sizing of the system, with a focus on how overall performance is affected by the definition of network boundaries. Upper bounds on integration schemes are provided considering both renewable penetration and needed reserve power capacity. The quantitative trade-off between grid extension, storage and optimal wind-solar mix is highlighted.This paper also brings insights on how optimal geographical distribution of renewable units evolves as a function of renewable penetration and grid extent.
基金Project supported by the Science Faculty Strategic Research of HongKong Baptist University(No.FRG/03-04/II-51)the Environment and Conservation Fund of Hong Kong Environmental Protection Department(No.16/2003)the National Natural Science Foundation of China(No.20307012).
文摘Spatial and temporal distribution of octylphenol （OP） and nonylphenol （NP） in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from 11 sites during the period of September- December 2004. Concentrations of OP and NP ranged from 11.3 to 348 ng/L and from 29 to 2591 ng/L, respectively. The high levels of NP and OP were found in November and December than in September and October. The levels of OP and NP have no significant spatial differences except September. Total organic matter in the sediments appeared to be an important factor in controlling the fate of these compounds in the aquatic environment.
文摘In order to understand the mechanisms on the variation between rice cultivars in Cd uptake and accumulation, two pot soil experiments were conducted with typical rice cultivars that varied greatly in soil Cd uptake. The experiments with six rice cultivars showed that the root oxidation abilities of rice differed with rice cultivars and also with types of the cultivars, the cultivars with indica consanguinity were significantly higher than the cultivars with japonica consanguinity. Root oxidation abilities of the rice cultivars correlated positively and significantly （P〈0.01） with their Cd concentrations and Cd quantity accumulations in rice plants. The experiments with two rice cultivars showed that significant differences also existed between the two cultivars in pot soil redox potentials, which of Shan you 63 （higher soil Cd accumulator） were significantly higher than that of Wu yun jing 7 （lower soil Cd accumulator） under different soil Cd levels, but the degrees of the differences varied with soil Cd levels. The differences were larger under soil Cd treatments than the control. The results indicate that root oxidation ability, especially in Cd contaminated soil, is one of the main mechanisms which dominate Cd uptake and accumulation by rice plant.
基金This research used data and documents from the project“Planning the ground level and urban surface water drainage in Binh Duong Province”.We sincerely thank the organizations related to this project.
文摘The purpose of this paper was to assess the impact of urbanization on the groundwater level(GWL)in aquifers of Binh Duong(BD)Province.The research method is to analyze the trend of GWL,the recharge capacity of surface over time and the relationship between them.The data of the GWL used in the study are the average values in the dry and rainy seasons of 35 observation wells from 2011 to 2018,which are in Pleistocene and Pliocene aquifers.The ability to recharge groundwater from the surface in this study was represented by the curve number(CN),a parameter used in hydrology for calculating direct runoff or infiltration from rainfall.The land use data to identify the CN was analyzed from the Landsat images.The results show that besides over-exploitation,the change of surface characteristic due to the urbanization development process is also the cause of the GWL decline.The analysis of seasonal GWL data shows that the increase in impervious surface area is the cause of GWL decline in the Pleistocene aquifer,which is more evident in the rainy season than in the dry season.The statistical results also show that in the rainy season and in shallow aquifers,a higher CN change can be found with the wells that had a remarkable GWL decline compared to the remaining wells.
文摘This paper presents the results of an experimental study on the influences of floodplain impermeable groynes on flow structure, velocity, and water depth around the groyne（s）. A wooden symmetrical compound channel was used. Groyne models with three different groyne relative lengths, 0.5, 0.75, and 1.0, were used on one floodplain with single and series arrangements. Analysis of the experimental results using the measured flow velocity and water depth values showed that flow structure, velocity, and water depth mainly depend on groyne relative length and the relative distance between series groynes. The flow velocity at the main channel centerline increased by about 40%, 60%, and 85%, and in other parts on the horizontal plane at the floodplain mid-water, depth by about 75%, 125%, and 175% of its original value in eases of one-side floodplain groyne（s） with relative lengths of 0.5, 0.75, and 1.0, respectively. The effective distance between two groynes in series arrangement ranges from 3 to 4 times the groyne length. Using an impermeable groyne with a large relative length in river floodplains increases the generation of eddy and roller zones downstream of the groyne, leading to more scouring and deposition. To avoid that, the groyne relative length must be kept below half the floodplain width,
文摘We have arrived at a critical juncture when it comes to understanding the numerous ways in which trade interacts with climate change and energy(trade-climate-energy nexus).Trade remains crucial for the sustainable development of the world's greatest trading nation:China.After clarifying the linkages within the trade,climate change and energy nexus,this article delves into China's specific needs and interests related to trade,climate change and energy.Then it explores the ways in which trade can contribute to China's needs,to sustainable energy development and to the goals of the global climate agreement that is under negotiation.One main findings are China is a key participant in negotiations on trade liberalization of environmental technologies and services.These negotiations are in China's interests in terms of innovative industries,technological upgrading,employment and public health.China could stand up for the interests of other emerging and developing countries and serve as an example in terms of transitioning to a low-carbon economy.Beyond trade barriers issues of domestic(energy)regulation such as fossil-fuel subsidies as well as investment,competition-policy,tradefacilitation and transit issues related to clean energy need to be addressed.Building trust between relevant actors across sectors and national borders will be of the essence in order to foster long-term cooperation on technological innovation.As a way forward,different approaches towards the governance of trade and climate change will be highlighted.Besides discussing the specific aspects of Chinese participation in global trade and climate change governance,this paper aims at offering broader insights into the nexus between trade,energy and climate governance in China.
基金supported by a grant from Wonkwang University in 2017
文摘Neurotoxicity induced by stress,radiation,chemicals,or metabolic diseases,is commonly associated with excitotoxicity,oxidative stress,and neuroinflammation.The pathological process of neurotoxicity induces neuronal death,interrupts synaptic plasticity in the brain,and is similar to that of diverse neurodegenerative diseases.Animal models of neurotoxicity have revealed that clinical symptoms and brain lesions can recover over time via neuroregenerative processes.Specifically,brain-derived neurotropic factor（BDNF） and gamma-aminobutyric acid（GABA）-ergic transmission are related to both neurodegeneration and neuroregeneration.This review summarizes the accumulating evidences that suggest a pathogenic role of BDNF and GABAergic transmission,their underlying mechanisms,and the relationship between BDNF and GABA in neurodegeneration and neuroregeneration.This review will provide a comprehensive overview of the underlying mechanisms of neuroregeneration that may help in developing potential strategies for pharmacotherapeutic approaches to treat neurotoxicity and neurodegenerative disease.
