The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role...The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production（EDSP） model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors（favorable spawning habitat areas with sea surface temperature of 16–18°C） were assumed to be closely associated with carrying capacity（K） in the EDSP model. Deviance Information Criterion（DIC） values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield（MSY） from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F（0.1） and F（MSY）. Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management.展开更多
In this study, the horizontal and vertical distribution of primary production(PP) and its monthly variations were described based on field data collected from the Daya Bay in January–December of 2016. The relationshi...In this study, the horizontal and vertical distribution of primary production(PP) and its monthly variations were described based on field data collected from the Daya Bay in January–December of 2016. The relationships between PP and environmental factors were analyzed using a general additive model(GAM). Significant seasonal differences were observed in the horizontal distribution of PP, while vertical distribution showed a relatively consistent unimodal pattern. The monthly average PP(calculated by carbon) ranged from 48.03 to 390.56 mg/(m~2·h),with an annual average of 182.77 mg/(m~2·h). The highest PP was observed in May and the lowest in November.Additionally, the overall trend in PP was spring>summer>winter>autumn, and spring PP was approximately three times that of autumn PP. GAM analysis revealed that temperature, bottom salinity, phytoplankton, and photosynthetically active radiation(PAR) had no significant relationships with PP, while longitude, depth, surface salinity, chlorophyll a(Chl a) and transparency were significantly correlated with PP. Overall, the results presented herein indicate that monsoonal changes and terrestrial and offshore water systems have crucial effects on environmental factors that are associated with PP changes.展开更多
Tritium release is one of the most concerning topics in nuclear power plants. Here, the tritium production in a 2 MW liquid-fueled molten salt experimental reactor(TMSR-LF1) was calculated by ORIGEN-S with an updated ...Tritium release is one of the most concerning topics in nuclear power plants. Here, the tritium production in a 2 MW liquid-fueled molten salt experimental reactor(TMSR-LF1) was calculated by ORIGEN-S with an updated cross-section library generated by TRITON in SCALE 6.1.3 code system. The results show that the tritium production rate and normalized tritium production rate of TMSR-LF1 are 8.90x10^(11)Bq/day and4.45x10^(11)Bq/(MW day), respectively. The environmental impact of tritium was analyzed via PC-CREAM 08 with an assumed 36 % release rate of tritium referring to the molten salt reactor experiment. During normal operations, the maximum tritium concentration is 1.4 Bq/m^3 under normal condition, and the corresponding individual dose to the public is about 1 μSv/a; under extreme conditions, the maximum concentration and corresponding individual doses are 11.8 Bq/m^3 and 9 μSv/a, respectively.Ingestion is the main exposure pathway and accounts for62 % of the total dose. Of this, 35 % is from organically bound tritium.展开更多
Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consum...Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consumption and environmental impacts of machining processes greatly focuses on design and planning activities, but is reasonably sparse for production operation activities. This paper explores a systematic methodology that incorporates energy consumption and environmental impact considerations into the production operation of machining processes. Firstly, the framework of the methodology is proposed to establish the generic procedures for integrating the above considerations in production operation activities. As the two key issues of the framework, the profile index value matrix is determined by valuing the individual quantity of energy consumption and environmental impacts of machining each job on each machine, and the multi-criteria models are constructed by the operational methods. Furthermore, with the guideline of the framework, the specific formulations are modeled by two sub-models for the parallel machine scheduling problem, in which makespan and energy consumption are the optimizing objectives as well as the constraints of environmental impact considerations. The specific formulations provide a practical method to integrate energy consumption and environmental impact considerations into the scheduling activity, and also can serve as a reference to other activities in the production operation. The case study for a batch of jobs, including seven kinds of gears in the machining shop floor, is presented to demonstrate the application of the specific formulations of the methodology. The proposed methodology provides potential opportunities for reducing energy consumption and environmental impacts in machining processes, and helps production managers in decision-making on the issues of energy consumption and environmental impacts in the production operation.展开更多
To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on...To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on the estimated frontier and technical inefficiency levels, we used the method developed by Reinhard, et al.[1] to estimate the environmental efficiency. Pesticide and chemical fertilizer inputs were treated as environmentally detrimental inputs. Results From estimated results, the mean environmental efficiency for pesticide input was 69.7%, indicating a great potential for reducing pesticide use in China’s vegetable production. In addition, substitution and output elasticities for vegetable farms were estimated to provide farmers with helpful information on how to reallocate input resources and improve efficiency. Conclusion There exists a great potential for reducing pesticide use in China’s vegetable production.展开更多
Tanzanian forests are excessively threatened by increased charcoal production fuelled by increased demand crucially in Dar es Salaam city which consumes nearly 70% of all the charcoal produced in the country. Through ...Tanzanian forests are excessively threatened by increased charcoal production fuelled by increased demand crucially in Dar es Salaam city which consumes nearly 70% of all the charcoal produced in the country. Through use of ecological modeling software STELLA? the environmental burden of charcoal production and use in Tanzania has been established. The study has revealed that the country losses 150,433 ha of forest per year. Due to increase in population by year 2030 almost 2.8 million ha of forests will have been lost. This is equivalent to 8.5% of the total forest cover the country had in 2009. The environmental burden includes air pollution characterized by a total emission of 49, 1.0, and 9.0, 12 million tonnes of CO2, SO2, NOx, and CH4, respectively by 2030. Other adverse impacts include loss of forest cover which ultimately causes degradation of soil quality by increased soil erosion, degradation of water sources and disruption of rainfall pattern including inducing draught. Taking into account that the agriculture in Tanzania is primarily rain fed, this has an adverse impact in agricultural production. In the current exploitation of this important natural resource, its sustainability is severely challenged and the whole concept of the forest being renewable is put into question. From these findings, it is recommended that concrete and deliberate efforts be made to reduce and eventually prohibit the use of charcoal in cities and towns.展开更多
[ Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production, the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied...[ Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production, the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. [ Method ] Three kinds of pyrethroids （permethrin, cyfluthrin and c/s-cypermethrin） were adminis- trated to two media （cut tobacco and iron sheet surface） in cigarette production environment at MRLs concentration, and the first sampling was conducted at 24 d post administration. Afterwards, sampling was performed once every 7 d, with a total of six times. The degradation rates of insecticides in different media were cal- culated, and degradation models were established. [ Result ] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and degradation rates presented the trend of fast-slow-fast ; the degradation rates of permethrin, cyfluthrin and c/s-cypermethrin in cut tobacco at 36 d post ad- ministration were 97.14%, 88.89% and 95.38%, respectively; the degradation rates on iron sheet surface were 29.95%, 48.99% and 40. 24%, respectively. The half lives of three kinds of insecticides in cut tobacco were 1 -2 d, while those on iron sheet surface were 6 - 10 d. [ Conclusion] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and their degradation regularity accorded with first order kinetic equation.展开更多
The biodiversity-productivity relationship is an important topic in the research of biodiversity and ecosystem function. The plant diversity productivity pattern is commonly unimodal and positively correlated. This pa...The biodiversity-productivity relationship is an important topic in the research of biodiversity and ecosystem function. The plant diversity productivity pattern is commonly unimodal and positively correlated. This paper researches the characteristics of plant diversity-productivity patterns in the Bayanbuluk alpine steppe in the central Tianshan Mountains, Xinjiang, China, and analyzes the effects of environmental factors on the distribution of plant communities, species composition, plant diversity and productivity in the steppe. The results show a positive correlation between plant diversity and productivity. DCCA (detrended canonical correspondence analysis) ordination reveals a significant relationship between the effects of air temperature, soil moisture content, available soil nitrogen, relative humidity and pH value on the distribution and composition of plant communities. There are significant correlations between the soil moisture content, relative humidity, pH value, air temperature and species richness and the aboveground biomass of Gramineae and Cyperaceae, and also significant correlations between the relative humidity, pH values and the total aboveground biomass of plant communities.展开更多
Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the...Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon （20.2 ±3.88） g kg^-1, total nitrogen （2.09±0.55） g kg^-1, and available phosphorus （42.7 ±32.7） mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil （0-10 cm） of highly productive paddy fields were （142.7 ~ 41.1） mg kg-~ and （36.2~ 10.4）% of added P, and CEC （7.93 ~ 1.32） cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.展开更多
Environmental protection products and equipment are important substance basis and insurance which provide supporting for to the realization of the strategic objective of reduced energy use and emissions while improvin...Environmental protection products and equipment are important substance basis and insurance which provide supporting for to the realization of the strategic objective of reduced energy use and emissions while improving the resource economy ＆ environmental kindly society building, as well as the sustainable development economy and environment in a sustainable fashion. Here, the framework of the standards system and evaluation indicators system for environmental protection products are described based on the present deficiencies in independent innovation, lower levels of standardization, and poor operating effectiveness of such equipment in China with a goal of forcing the development of standardization, seriation and currency used in the environmental protection industry. The results presented here should serve as a reference for the promotion of quality and effectiveness in environmental protection products and equipments.展开更多
The Ecological-living-productive land(ELPL)classification system was proposed in an effort to steer China's land pattern to an ecological-centered path,with the development model shifting from a single function in...The Ecological-living-productive land(ELPL)classification system was proposed in an effort to steer China's land pattern to an ecological-centered path,with the development model shifting from a single function into more integrated multifunction land use.The focus is coordinating the man-land contradictions and developing an intensive,efficient and sustainable land use policy in an increasingly tense relationship between humans and nature.Driven by socioeconomic change and rapid population growth,many cities are undergoing urban sprawl,which involves the consumption of cropland and ecological land and threatens the ecological balance.This paper aims to quantitatively analyze the critical effects of ELPL changes on eco-environmental quality according to land use classification based on leading function of ecology,living and production from 1990 to 2015 with a case study of Xining City.Also,four future land use scenarios were simulated for 2030 using the Future Land Use Simulation(FLUS)model that couples human and natural effects.Our results show a decrease in productive land(PL)and an increase in ecological land(EL)and living land(LL)in Xining City.Forestry ecological land(FEL)covered the top largest proportion;agriculture productive land(APL)showed the greatest reduction and urban and rural living land(U-RLL)presented a dramatic increase.The eco-environmental quality improved in 1990-2010,mainly affected by the conversion of APL to FEL and GEL.However,the encroachment of U-RLL into APL,other ecological land(OEL)and FEL was the main contributor to the decline in eco-environmental quality in 2010-2015 as well as the primary reason for the increase area of lower-quality.The Harmonious Development(HD)-Scenario,characterized by a rational allocation of LL and PL and a better eco-environment,would have implications for planning and monitoring future management of ELPL,and may represent a valuable reference for local policy-makers.展开更多
The aim of this survey?was to identify the active ingredients of phytosanitary products generally used in the market-gardening, to evaluate the behavior of market gardeners, environmental and sanitary risks link to th...The aim of this survey?was to identify the active ingredients of phytosanitary products generally used in the market-gardening, to evaluate the behavior of market gardeners, environmental and sanitary risks link to the use of phytosanitary products. Results revealed that 8 actives ingredients are regularly used: paraquat, atrazine, glyphosate, chlorpyrifos-éthyl, cypermethrin, maneb, mancozeb and diuron. The contamination of running water and rivers is caused by the fact that 81.25% of them are washing their pulverization equipments in these last ones. Moreover, 72.90% release empty packages of pesticides in the farm which will be carried away by running water. 59.09% adopt the overdose strategy in case of insufficient treatment. The inadequate equipment of protection and the consumption of surrounding water by 51.10% represent a danger for the health of market gardeners. Thus, headache and stomachache are the most recorded intoxications.展开更多
This study assessed the effectiveness of mitigation measures adopted to address the environmental effects of oil and gas industries from the perspective of compliance, cost of production, and community awareness. The ...This study assessed the effectiveness of mitigation measures adopted to address the environmental effects of oil and gas industries from the perspective of compliance, cost of production, and community awareness. The research applied a case study through multi-method-qualitative and quantitative approaches. The target population of 547,368 people involved people in Takoradi, Shama and Newtown communities. A sample size of </span><span style="font-family:Verdana;">150</span><span style="font-family:Verdana;"> was selected and categorised under 36% for Shama, 30% for Newtown and 34% for Takoradi. A combination of probability (simple random) and non-probability (cluster and convenience) sampling frames were used to access the respondents for the study. Data collection tools were limited to questionnaires and interview sessions. The descriptive statistics, Relative Importance Index (RII) and significance testing using a one-sample t-test module guided the analysis. Interview sessions were compiled into transcripts and later categorized into themes that directly reflected the patterns of the questions on the questionnaire. The conclusion rated major decisions in mitigating oil and gas impacts on the environment as first for conscious effort to package fuel and other chemicals in safe storages, followed by the use of best road systems to reduce the risk of accidents, then application of strict rules and regulations to curb impacts and lastly capacity building for participants in the oil and gas production industry. While significant measures have been adopted to mitigate the effects of oil and gas exploration, there remain challenges with effectiveness as a result of weakness in community involvement efforts, lack of motivation, weak laws and regulations and loss of respect. For effectiveness in reducing the challenges to mitigate the environmental impacts of the oil and gas production activity, policymakers, as well as the practitioners in the oil production industry, are advised to motivate people into buying into their policy to reduce such impacts.展开更多
Using input, output and pollution data of industrial enterprises in 30 Chinese provinces and municipalities from 1998 to 2005, this paper creates an environmental production frontier function model to assess China'...Using input, output and pollution data of industrial enterprises in 30 Chinese provinces and municipalities from 1998 to 2005, this paper creates an environmental production frontier function model to assess China's industrial growth sources, particularly environmental control and changes in the industrial environmental structure's impact on industrial productivity. It found that (1) at its current stage, China's rapid industrial growth is accompanied by a slow increase in pollution; (2) environmental total factor productivity has become a primary driver of rapid growth with less pollution; (3) environmental control didn't cause any substantial restraint on China's industrial growth; (4) improvement in industrial environmental structure contributes an increasingly large share to economic growth with less pollution. China's industrial productivity is increasing, its growth model is being transformed, and the environment is exerting a diminishing constraint on economic growth.展开更多
目的通过量化分析马口铁奶粉罐在从“摇篮到大门”生命周期内的环境足迹,识别其生产过程中的关键环境影响类别和最相关生命周期阶段,并提出降低环境负担的建议。方法基于欧盟产品环境足迹方法,利用SimaPro生命周期评价软件和Ecoinvent...目的通过量化分析马口铁奶粉罐在从“摇篮到大门”生命周期内的环境足迹,识别其生产过程中的关键环境影响类别和最相关生命周期阶段,并提出降低环境负担的建议。方法基于欧盟产品环境足迹方法,利用SimaPro生命周期评价软件和Ecoinvent数据库对奶粉罐进行生命周期建模,随后采用环境足迹(Environmental footprint,EF)3.1方法对16类环境足迹指标进行评估,并进一步对关键参数和数据库进行敏感性分析。结果气候变化、矿物与金属资源消耗、化石资源利用、颗粒物形成、人类毒性-癌症和酸化是奶粉罐生产过程中值得重点关注的最相关环境影响类别。生产1个奶粉罐的碳足迹为0.34 kg CO_(2) eq.,主要归因于马口铁原料造成的能源和资源消耗,其贡献率达61.76%。能源结构由传统火电向清洁能源的转型可以减少奶粉罐生产过程中2.94%~11.84%的温室气体排放。结论提高原辅料利用效率、减少废料产生、降低电能消耗并加速清洁能源替代,是降低奶粉罐生命周期内环境足迹的有效路径。展开更多
基金The National Natural Science Foundation of China under contract No.NSFC31702343the Science Foundation of Shanghai under contract No.13ZR1419700+4 种基金the Innovation Program of Shanghai Municipal Education Commission under contract No.13YZ091the National High-tech R&D Program of China(863 Program)under contract No.2012AA092303the Funding Program for Outstanding Dissertations in Shanghai Ocean Universitythe Funding Scheme for Training Young Teachers in Shanghai Colleges and the Shanghai Leading Academic Discipline Project(Fisheries Discipline)Involvement of Chen Yong was supported by SHOU International Center for Marine Studies and Shanghai 1000 Talent Program
文摘The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production（EDSP） model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors（favorable spawning habitat areas with sea surface temperature of 16–18°C） were assumed to be closely associated with carrying capacity（K） in the EDSP model. Deviance Information Criterion（DIC） values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield（MSY） from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F（0.1） and F（MSY）. Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management.
基金The National Natural Science Foundation of China under contract No.41506136the Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2015005
文摘In this study, the horizontal and vertical distribution of primary production(PP) and its monthly variations were described based on field data collected from the Daya Bay in January–December of 2016. The relationships between PP and environmental factors were analyzed using a general additive model(GAM). Significant seasonal differences were observed in the horizontal distribution of PP, while vertical distribution showed a relatively consistent unimodal pattern. The monthly average PP(calculated by carbon) ranged from 48.03 to 390.56 mg/(m~2·h),with an annual average of 182.77 mg/(m~2·h). The highest PP was observed in May and the lowest in November.Additionally, the overall trend in PP was spring>summer>winter>autumn, and spring PP was approximately three times that of autumn PP. GAM analysis revealed that temperature, bottom salinity, phytoplankton, and photosynthetically active radiation(PAR) had no significant relationships with PP, while longitude, depth, surface salinity, chlorophyll a(Chl a) and transparency were significantly correlated with PP. Overall, the results presented herein indicate that monsoonal changes and terrestrial and offshore water systems have crucial effects on environmental factors that are associated with PP changes.
文摘Tritium release is one of the most concerning topics in nuclear power plants. Here, the tritium production in a 2 MW liquid-fueled molten salt experimental reactor(TMSR-LF1) was calculated by ORIGEN-S with an updated cross-section library generated by TRITON in SCALE 6.1.3 code system. The results show that the tritium production rate and normalized tritium production rate of TMSR-LF1 are 8.90x10^(11)Bq/day and4.45x10^(11)Bq/(MW day), respectively. The environmental impact of tritium was analyzed via PC-CREAM 08 with an assumed 36 % release rate of tritium referring to the molten salt reactor experiment. During normal operations, the maximum tritium concentration is 1.4 Bq/m^3 under normal condition, and the corresponding individual dose to the public is about 1 μSv/a; under extreme conditions, the maximum concentration and corresponding individual doses are 11.8 Bq/m^3 and 9 μSv/a, respectively.Ingestion is the main exposure pathway and accounts for62 % of the total dose. Of this, 35 % is from organically bound tritium.
基金supported by National Natural Science Foundation of China (Grant No. 50775228)Program for New Century Excellent Talents in University of Ministry of Education, China (Grant No. NCET-07-0907)Chongqing Provincal Natural Science Foundation of China (Grant No. 2010BB0055)
文摘Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consumption and environmental impacts of machining processes greatly focuses on design and planning activities, but is reasonably sparse for production operation activities. This paper explores a systematic methodology that incorporates energy consumption and environmental impact considerations into the production operation of machining processes. Firstly, the framework of the methodology is proposed to establish the generic procedures for integrating the above considerations in production operation activities. As the two key issues of the framework, the profile index value matrix is determined by valuing the individual quantity of energy consumption and environmental impacts of machining each job on each machine, and the multi-criteria models are constructed by the operational methods. Furthermore, with the guideline of the framework, the specific formulations are modeled by two sub-models for the parallel machine scheduling problem, in which makespan and energy consumption are the optimizing objectives as well as the constraints of environmental impact considerations. The specific formulations provide a practical method to integrate energy consumption and environmental impact considerations into the scheduling activity, and also can serve as a reference to other activities in the production operation. The case study for a batch of jobs, including seven kinds of gears in the machining shop floor, is presented to demonstrate the application of the specific formulations of the methodology. The proposed methodology provides potential opportunities for reducing energy consumption and environmental impacts in machining processes, and helps production managers in decision-making on the issues of energy consumption and environmental impacts in the production operation.
文摘To analyze and estimate the environmental efficiency of China’s vegetable production. Methods The stochastic translog frontier model was used to estimate the technical efficiency of vegetable production. Based on the estimated frontier and technical inefficiency levels, we used the method developed by Reinhard, et al.[1] to estimate the environmental efficiency. Pesticide and chemical fertilizer inputs were treated as environmentally detrimental inputs. Results From estimated results, the mean environmental efficiency for pesticide input was 69.7%, indicating a great potential for reducing pesticide use in China’s vegetable production. In addition, substitution and output elasticities for vegetable farms were estimated to provide farmers with helpful information on how to reallocate input resources and improve efficiency. Conclusion There exists a great potential for reducing pesticide use in China’s vegetable production.
文摘Tanzanian forests are excessively threatened by increased charcoal production fuelled by increased demand crucially in Dar es Salaam city which consumes nearly 70% of all the charcoal produced in the country. Through use of ecological modeling software STELLA? the environmental burden of charcoal production and use in Tanzania has been established. The study has revealed that the country losses 150,433 ha of forest per year. Due to increase in population by year 2030 almost 2.8 million ha of forests will have been lost. This is equivalent to 8.5% of the total forest cover the country had in 2009. The environmental burden includes air pollution characterized by a total emission of 49, 1.0, and 9.0, 12 million tonnes of CO2, SO2, NOx, and CH4, respectively by 2030. Other adverse impacts include loss of forest cover which ultimately causes degradation of soil quality by increased soil erosion, degradation of water sources and disruption of rainfall pattern including inducing draught. Taking into account that the agriculture in Tanzania is primarily rain fed, this has an adverse impact in agricultural production. In the current exploitation of this important natural resource, its sustainability is severely challenged and the whole concept of the forest being renewable is put into question. From these findings, it is recommended that concrete and deliberate efforts be made to reduce and eventually prohibit the use of charcoal in cities and towns.
基金Supported by Standard Project of State Tobacco Monopoly Administration(2014B023)
文摘[ Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production, the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. [ Method ] Three kinds of pyrethroids （permethrin, cyfluthrin and c/s-cypermethrin） were adminis- trated to two media （cut tobacco and iron sheet surface） in cigarette production environment at MRLs concentration, and the first sampling was conducted at 24 d post administration. Afterwards, sampling was performed once every 7 d, with a total of six times. The degradation rates of insecticides in different media were cal- culated, and degradation models were established. [ Result ] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and degradation rates presented the trend of fast-slow-fast ; the degradation rates of permethrin, cyfluthrin and c/s-cypermethrin in cut tobacco at 36 d post ad- ministration were 97.14%, 88.89% and 95.38%, respectively; the degradation rates on iron sheet surface were 29.95%, 48.99% and 40. 24%, respectively. The half lives of three kinds of insecticides in cut tobacco were 1 -2 d, while those on iron sheet surface were 6 - 10 d. [ Conclusion] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and their degradation regularity accorded with first order kinetic equation.
基金supported by the Global Environmental Foundation (The grassland program of Xinjiang province,China)
文摘The biodiversity-productivity relationship is an important topic in the research of biodiversity and ecosystem function. The plant diversity productivity pattern is commonly unimodal and positively correlated. This paper researches the characteristics of plant diversity-productivity patterns in the Bayanbuluk alpine steppe in the central Tianshan Mountains, Xinjiang, China, and analyzes the effects of environmental factors on the distribution of plant communities, species composition, plant diversity and productivity in the steppe. The results show a positive correlation between plant diversity and productivity. DCCA (detrended canonical correspondence analysis) ordination reveals a significant relationship between the effects of air temperature, soil moisture content, available soil nitrogen, relative humidity and pH value on the distribution and composition of plant communities. There are significant correlations between the soil moisture content, relative humidity, pH value, air temperature and species richness and the aboveground biomass of Gramineae and Cyperaceae, and also significant correlations between the relative humidity, pH values and the total aboveground biomass of plant communities.
基金supported by the National Natural Science Foundation of China(40471066)the Knowledge Innovation Program of the Chinese Academy of Sciences(KZCX1-SW-01-05).
文摘Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon （20.2 ±3.88） g kg^-1, total nitrogen （2.09±0.55） g kg^-1, and available phosphorus （42.7 ±32.7） mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil （0-10 cm） of highly productive paddy fields were （142.7 ~ 41.1） mg kg-~ and （36.2~ 10.4）% of added P, and CEC （7.93 ~ 1.32） cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.
文摘Environmental protection products and equipment are important substance basis and insurance which provide supporting for to the realization of the strategic objective of reduced energy use and emissions while improving the resource economy ＆ environmental kindly society building, as well as the sustainable development economy and environment in a sustainable fashion. Here, the framework of the standards system and evaluation indicators system for environmental protection products are described based on the present deficiencies in independent innovation, lower levels of standardization, and poor operating effectiveness of such equipment in China with a goal of forcing the development of standardization, seriation and currency used in the environmental protection industry. The results presented here should serve as a reference for the promotion of quality and effectiveness in environmental protection products and equipments.
基金the support of the National Natural Science Foundation of China(No.41661038)Soft Science Research Project of Science and Technology Department of Qinghai province(No.2015-ZJ-602)
文摘The Ecological-living-productive land(ELPL)classification system was proposed in an effort to steer China's land pattern to an ecological-centered path,with the development model shifting from a single function into more integrated multifunction land use.The focus is coordinating the man-land contradictions and developing an intensive,efficient and sustainable land use policy in an increasingly tense relationship between humans and nature.Driven by socioeconomic change and rapid population growth,many cities are undergoing urban sprawl,which involves the consumption of cropland and ecological land and threatens the ecological balance.This paper aims to quantitatively analyze the critical effects of ELPL changes on eco-environmental quality according to land use classification based on leading function of ecology,living and production from 1990 to 2015 with a case study of Xining City.Also,four future land use scenarios were simulated for 2030 using the Future Land Use Simulation(FLUS)model that couples human and natural effects.Our results show a decrease in productive land(PL)and an increase in ecological land(EL)and living land(LL)in Xining City.Forestry ecological land(FEL)covered the top largest proportion;agriculture productive land(APL)showed the greatest reduction and urban and rural living land(U-RLL)presented a dramatic increase.The eco-environmental quality improved in 1990-2010,mainly affected by the conversion of APL to FEL and GEL.However,the encroachment of U-RLL into APL,other ecological land(OEL)and FEL was the main contributor to the decline in eco-environmental quality in 2010-2015 as well as the primary reason for the increase area of lower-quality.The Harmonious Development(HD)-Scenario,characterized by a rational allocation of LL and PL and a better eco-environment,would have implications for planning and monitoring future management of ELPL,and may represent a valuable reference for local policy-makers.
文摘The aim of this survey?was to identify the active ingredients of phytosanitary products generally used in the market-gardening, to evaluate the behavior of market gardeners, environmental and sanitary risks link to the use of phytosanitary products. Results revealed that 8 actives ingredients are regularly used: paraquat, atrazine, glyphosate, chlorpyrifos-éthyl, cypermethrin, maneb, mancozeb and diuron. The contamination of running water and rivers is caused by the fact that 81.25% of them are washing their pulverization equipments in these last ones. Moreover, 72.90% release empty packages of pesticides in the farm which will be carried away by running water. 59.09% adopt the overdose strategy in case of insufficient treatment. The inadequate equipment of protection and the consumption of surrounding water by 51.10% represent a danger for the health of market gardeners. Thus, headache and stomachache are the most recorded intoxications.
文摘This study assessed the effectiveness of mitigation measures adopted to address the environmental effects of oil and gas industries from the perspective of compliance, cost of production, and community awareness. The research applied a case study through multi-method-qualitative and quantitative approaches. The target population of 547,368 people involved people in Takoradi, Shama and Newtown communities. A sample size of </span><span style="font-family:Verdana;">150</span><span style="font-family:Verdana;"> was selected and categorised under 36% for Shama, 30% for Newtown and 34% for Takoradi. A combination of probability (simple random) and non-probability (cluster and convenience) sampling frames were used to access the respondents for the study. Data collection tools were limited to questionnaires and interview sessions. The descriptive statistics, Relative Importance Index (RII) and significance testing using a one-sample t-test module guided the analysis. Interview sessions were compiled into transcripts and later categorized into themes that directly reflected the patterns of the questions on the questionnaire. The conclusion rated major decisions in mitigating oil and gas impacts on the environment as first for conscious effort to package fuel and other chemicals in safe storages, followed by the use of best road systems to reduce the risk of accidents, then application of strict rules and regulations to curb impacts and lastly capacity building for participants in the oil and gas production industry. While significant measures have been adopted to mitigate the effects of oil and gas exploration, there remain challenges with effectiveness as a result of weakness in community involvement efforts, lack of motivation, weak laws and regulations and loss of respect. For effectiveness in reducing the challenges to mitigate the environmental impacts of the oil and gas production activity, policymakers, as well as the practitioners in the oil production industry, are advised to motivate people into buying into their policy to reduce such impacts.
基金support by National Fund for Social Sciences (Project Number: 07BJY019 and 2008AJY032)Cultural and Social Sciences Fund of the Ministry of Education (Project Number: 2008JYJ059)the financial support by New Century Talent Support Program of the Ministry of Education
文摘Using input, output and pollution data of industrial enterprises in 30 Chinese provinces and municipalities from 1998 to 2005, this paper creates an environmental production frontier function model to assess China's industrial growth sources, particularly environmental control and changes in the industrial environmental structure's impact on industrial productivity. It found that (1) at its current stage, China's rapid industrial growth is accompanied by a slow increase in pollution; (2) environmental total factor productivity has become a primary driver of rapid growth with less pollution; (3) environmental control didn't cause any substantial restraint on China's industrial growth; (4) improvement in industrial environmental structure contributes an increasingly large share to economic growth with less pollution. China's industrial productivity is increasing, its growth model is being transformed, and the environment is exerting a diminishing constraint on economic growth.
文摘目的通过量化分析马口铁奶粉罐在从“摇篮到大门”生命周期内的环境足迹,识别其生产过程中的关键环境影响类别和最相关生命周期阶段,并提出降低环境负担的建议。方法基于欧盟产品环境足迹方法,利用SimaPro生命周期评价软件和Ecoinvent数据库对奶粉罐进行生命周期建模,随后采用环境足迹(Environmental footprint,EF)3.1方法对16类环境足迹指标进行评估,并进一步对关键参数和数据库进行敏感性分析。结果气候变化、矿物与金属资源消耗、化石资源利用、颗粒物形成、人类毒性-癌症和酸化是奶粉罐生产过程中值得重点关注的最相关环境影响类别。生产1个奶粉罐的碳足迹为0.34 kg CO_(2) eq.,主要归因于马口铁原料造成的能源和资源消耗,其贡献率达61.76%。能源结构由传统火电向清洁能源的转型可以减少奶粉罐生产过程中2.94%~11.84%的温室气体排放。结论提高原辅料利用效率、减少废料产生、降低电能消耗并加速清洁能源替代,是降低奶粉罐生命周期内环境足迹的有效路径。
