The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-carotane.Abundant β-carotane has been well...The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-carotane.Abundant β-carotane has been well acknowledged as an effective indicator of biological sources or depositional environments.However,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng Fm.remains obscure.Based on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng Fm.The results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng Fm.The haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline lakes.The enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a threshold.The paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and precipitation.While it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.展开更多
Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessmen...Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario is conducted using SimaPro Ver. 8.1. The results of energy consumption and potential environmental impact of biochar-based bioenergy production system are compared with those of conventional coal-based system. Results show that biocbar land application consumes 4847.61 MJ per tonne dry feedstock more energy than conventional system, but reduces the GHG emissions by 68.19 kg CO2e per tonne of dry feed- stock in its life cycle. Biochar land application improves ecosystem quality by 18 %, reduces climate change by 15 %, and resource use by 13 % but may adversely impact on human health by increasing disability adjusted life years by 1.7 % if biomass availability is low to medium. Replacing fossil fuel with woody biomass has a positiveimpact on the environment, as one tonne of dry biomass feedstock when converted to biochar reduces up to 38 kg CO2e with biochar land application despite using more energy. These results will help understand a comprehensive picture of the new interventions in forestry businesses, which are promoting biochar-based bioenergy production.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
At the normal pool level of 175 m, the inundated areas of the Three Gorges Reservoir involve 2 cities, 11 county seats and 140 towns. The population of the cities and towns under the inundated line totals 393 000 peop...At the normal pool level of 175 m, the inundated areas of the Three Gorges Reservoir involve 2 cities, 11 county seats and 140 towns. The population of the cities and towns under the inundated line totals 393 000 people(1985). These affected cities and towns will be rebuilt by means of moving backward to a higher elevation or to other places.The cities and towns to be relocated are the regional political, economic and cultural centres, and serve as traffic complexes and places of goods gathering and distributing. They are also the seats containing some important cultural relics and historic sites, landscaping and scenic spots. The relocation of the cities and towns will generate far-reaching impacts on regional socio-economy and environment. The unreasonable excavation and fill or the improper protective measures adopted may induce land slide,collapse and soil loss. The ruins and wastes will affect the water quality in the early period of impoundment of the Three Gorges Reservoir. A large demand of timber may result in forest fall excessively in the local area of the reservoir region, and lower forest and vegetation coverage rate may lead to soil loss. The relocation of the cities and towns will increase urbanization in reservoir, improve the infrastructure, enhance their location function and economic radiation capacity. The negative impact will reach its maximum during relocation peak period, and the environmental quality will be progressively improved with the recovery of the functions of the relocated cities and towns and the implementation of environmental protection measures. Finally, the negative impact will be offset, and the negative impact will be changed into positive environmental elements.展开更多
Assessment system of implicit environmental impacts was established including environmental impact indicator, resources consumption indicator and energy consumption indicator. The quantification of environmental impac...Assessment system of implicit environmental impacts was established including environmental impact indicator, resources consumption indicator and energy consumption indicator. The quantification of environmental impact indicators is based on the life cycle assessment system of the Society of Environmental Toxicology and Chemistry (SETAC) and the evaluation software BEES. Normalization reference values and weights of 12 categories of environmental impacts were identified, and the environmental impact indicators in the phases of raw material extraction, transportation, manufacturing, use and end of life were analyzed. By analyzing the environmental performance of a university refectory as a case study, it is demonstrated that human health, global wanning and acidification are the first three environmental impacts in 12 categories. The total implicit environmental impact load per square meter of this project is 18.448 × 10 ^-2 standard human equivalent weight. Moreover, 97.3% of total environmental impacts occur in the phase of raw material extraction.展开更多
Substituted plan in the environmental impact assessment (EIA) mainly means the treatment technology and the substituted site of plant, and it also includes the many kinds of environment protection measures. This paper...Substituted plan in the environmental impact assessment (EIA) mainly means the treatment technology and the substituted site of plant, and it also includes the many kinds of environment protection measures. This paper will make detailed analysis on the treatment technology, the substituted site of plant, the purpose of discharged water and the dispose of sludge in the Yongchuan wastewater treatment project.展开更多
The land disturbance and its ecological impacts are the most significant one in the environmental problems which arise from increase of coal mining,processing and utilization. And the environmental impact assessment a...The land disturbance and its ecological impacts are the most significant one in the environmental problems which arise from increase of coal mining,processing and utilization. And the environmental impact assessment as one of the most powerful planning tools has been playing a good part in the environment protection in China. This paper ,based on EIA experience, discribes the methods of identification, prediction and analysis of the impacts of mining subsidence,the operational procedures and mitigating measures likely to take.展开更多
Lenzing is presenting an innovative eco denim concept TENCEL at the Parisian trade fairs of Expofil and Texworld, which will take place from 9 to 13 February 2009. An addition of as little as 25%
Due to large area disturbed and great deal of energy cost during skidding operations, introducing or applying the appropriate techniques of timber extracting could significantly reduce the impact of timber extraction ...Due to large area disturbed and great deal of energy cost during skidding operations, introducing or applying the appropriate techniques of timber extracting could significantly reduce the impact of timber extraction operations to forest environment while pursuing the reasonable operation costs. Four environmentally sound timber extraction techniques for small tree harvesting, particularly for thinning operations, were presented and introduced in this paper. The results of evaluation, test or practices indicated that these timber-extracting techniques are feasible, applicable and reasonable in small tree harvesting with a relatively low impact no environment and a moderate operation cost.展开更多
Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainabili...Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainability target of SEA, the content of ecosystem health as well as the interrelations between SEA and ecosystem health. For a good SEA, its ecological sustainability principles should be provided with distinct content and a general assessment system. A framework for ecosystem health assessment was established according to the content of ecosystem health, and combined into SEA as SEA抯 ecological sustainability target, we can effectively guide decision-makers to make suitable indigenous means and local solutions. , The basic principles and procedure of SEA for ecosystem health are also discussed in the paper.展开更多
基金financial support from the National Key Research and Development Program of China(2019YFC0605502)the National Natural Science Foundation of China(42302156)+1 种基金the Major Projects of Petro China Science and Technology Fund(2021DJ0206)the Natural Science Foundation of China University of Petroleum(22CX06046A)。
文摘The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-carotane.Abundant β-carotane has been well acknowledged as an effective indicator of biological sources or depositional environments.However,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng Fm.remains obscure.Based on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng Fm.The results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng Fm.The haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline lakes.The enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a threshold.The paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and precipitation.While it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.
基金supported by Natural Sciences and Engineering Research Council of Canada through Industrial Postgraduate Scholarships(NSERC-IPS)Ontario Graduate Scholarship (OGS)Ontario Power Generation(OPG)
文摘Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario is conducted using SimaPro Ver. 8.1. The results of energy consumption and potential environmental impact of biochar-based bioenergy production system are compared with those of conventional coal-based system. Results show that biocbar land application consumes 4847.61 MJ per tonne dry feedstock more energy than conventional system, but reduces the GHG emissions by 68.19 kg CO2e per tonne of dry feed- stock in its life cycle. Biochar land application improves ecosystem quality by 18 %, reduces climate change by 15 %, and resource use by 13 % but may adversely impact on human health by increasing disability adjusted life years by 1.7 % if biomass availability is low to medium. Replacing fossil fuel with woody biomass has a positiveimpact on the environment, as one tonne of dry biomass feedstock when converted to biochar reduces up to 38 kg CO2e with biochar land application despite using more energy. These results will help understand a comprehensive picture of the new interventions in forestry businesses, which are promoting biochar-based bioenergy production.
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.
文摘At the normal pool level of 175 m, the inundated areas of the Three Gorges Reservoir involve 2 cities, 11 county seats and 140 towns. The population of the cities and towns under the inundated line totals 393 000 people(1985). These affected cities and towns will be rebuilt by means of moving backward to a higher elevation or to other places.The cities and towns to be relocated are the regional political, economic and cultural centres, and serve as traffic complexes and places of goods gathering and distributing. They are also the seats containing some important cultural relics and historic sites, landscaping and scenic spots. The relocation of the cities and towns will generate far-reaching impacts on regional socio-economy and environment. The unreasonable excavation and fill or the improper protective measures adopted may induce land slide,collapse and soil loss. The ruins and wastes will affect the water quality in the early period of impoundment of the Three Gorges Reservoir. A large demand of timber may result in forest fall excessively in the local area of the reservoir region, and lower forest and vegetation coverage rate may lead to soil loss. The relocation of the cities and towns will increase urbanization in reservoir, improve the infrastructure, enhance their location function and economic radiation capacity. The negative impact will reach its maximum during relocation peak period, and the environmental quality will be progressively improved with the recovery of the functions of the relocated cities and towns and the implementation of environmental protection measures. Finally, the negative impact will be offset, and the negative impact will be changed into positive environmental elements.
基金The Research Fund for the Doctoral Pro-gram of Higher Education of China(No.20050487017)
文摘Assessment system of implicit environmental impacts was established including environmental impact indicator, resources consumption indicator and energy consumption indicator. The quantification of environmental impact indicators is based on the life cycle assessment system of the Society of Environmental Toxicology and Chemistry (SETAC) and the evaluation software BEES. Normalization reference values and weights of 12 categories of environmental impacts were identified, and the environmental impact indicators in the phases of raw material extraction, transportation, manufacturing, use and end of life were analyzed. By analyzing the environmental performance of a university refectory as a case study, it is demonstrated that human health, global wanning and acidification are the first three environmental impacts in 12 categories. The total implicit environmental impact load per square meter of this project is 18.448 × 10 ^-2 standard human equivalent weight. Moreover, 97.3% of total environmental impacts occur in the phase of raw material extraction.
文摘Substituted plan in the environmental impact assessment (EIA) mainly means the treatment technology and the substituted site of plant, and it also includes the many kinds of environment protection measures. This paper will make detailed analysis on the treatment technology, the substituted site of plant, the purpose of discharged water and the dispose of sludge in the Yongchuan wastewater treatment project.
文摘The land disturbance and its ecological impacts are the most significant one in the environmental problems which arise from increase of coal mining,processing and utilization. And the environmental impact assessment as one of the most powerful planning tools has been playing a good part in the environment protection in China. This paper ,based on EIA experience, discribes the methods of identification, prediction and analysis of the impacts of mining subsidence,the operational procedures and mitigating measures likely to take.
文摘Lenzing is presenting an innovative eco denim concept TENCEL at the Parisian trade fairs of Expofil and Texworld, which will take place from 9 to 13 February 2009. An addition of as little as 25%
基金Chinese National Research Funding for Young Scientist and Engineering Research Unit, USDA Forest Service.
文摘Due to large area disturbed and great deal of energy cost during skidding operations, introducing or applying the appropriate techniques of timber extracting could significantly reduce the impact of timber extraction operations to forest environment while pursuing the reasonable operation costs. Four environmentally sound timber extraction techniques for small tree harvesting, particularly for thinning operations, were presented and introduced in this paper. The results of evaluation, test or practices indicated that these timber-extracting techniques are feasible, applicable and reasonable in small tree harvesting with a relatively low impact no environment and a moderate operation cost.
文摘Strategic environment assessment (SEA) and ecosystem health are two new ideas on environmental management. On the basis of reviewing some relevant literature, this paper made discussions on the ecological sustainability target of SEA, the content of ecosystem health as well as the interrelations between SEA and ecosystem health. For a good SEA, its ecological sustainability principles should be provided with distinct content and a general assessment system. A framework for ecosystem health assessment was established according to the content of ecosystem health, and combined into SEA as SEA抯 ecological sustainability target, we can effectively guide decision-makers to make suitable indigenous means and local solutions. , The basic principles and procedure of SEA for ecosystem health are also discussed in the paper.