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Dynamic Changes of Nitrogen in Saline-alkaline Paddy Field and Its Potential Environmental Impacts 被引量:1
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作者 叶洁琼 袁瑞霞 +1 位作者 王兆慧 柳建设 《Agricultural Science & Technology》 CAS 2011年第3期443-446,460,共5页
[Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as stu... [Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as study object,field test method was used to explore the dynamic changes was strong alkof nitrogen in paddy field of the region and its potential impact on environment. [Result] The soil in test regionaline with high CEC and C/N ratios,as well as poor preserving capacity of fertilizer. During the two-year field experiment,the indicators of salinization fluctuated. Initially,the concentrations of total nitrogen and ammonia nitrogen reached their maximum values,then decreased over time as a result of heavy rain. The maximum of nitrate concentration appeared later than those of total nitrogen and ammonia nitrogen. Ammonia volatilization accounted for 18.9%-28.8% of the nitrogen loss. The total nitrogen concentration in surface water was higher than the national Class Ⅲ surface water environmental quality standard. The concentration of ammonia from the recession flow of agricultural field was considerably high,which would potentially threaten the fishery in the downstream of Chagan Lake. [Conclusion] The study provided theoretical basis for saline-alkaline soil management and conservation of water and fishery resources. 展开更多
关键词 Saline-alkaline soil NITROGEN Dynamic changes potential environmental impact
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Dynamic Variation Characteristics of Phosphorus in Paddy Field Runoff in Saline Land and Its Potential Environmental Effect 被引量:2
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作者 YUAN Rui-xia YE Jie-qiong +1 位作者 WANG Zhao-hui LIU Jian-she 《Meteorological and Environmental Research》 CAS 2011年第4期72-75,78,共5页
[Objective]The aim was to study the dynamic variation characteristics of phosphorus in paddy field runoff in saline land and its potential environmental effect.[Method]Taking Qianguo irrigation district in soda-saline... [Objective]The aim was to study the dynamic variation characteristics of phosphorus in paddy field runoff in saline land and its potential environmental effect.[Method]Taking Qianguo irrigation district in soda-saline land in Songnen Plain as study object,the dynamic variation law of phosphorus in paddy field runoff under different irrigation conditions and its potential environmental effect were discussed.[Result]Surface water in paddy field was alkaline,and scattered soil had poor fertilizer conservation capacity.Phosphorus accumulated in soil surface,which could increase the risk of phosphorus loss.Phosphorus loss in paddy field mainly occurred in irrigation period and runoff period caused by rainstorm.The concentration of total phosphorus(TP),particulate phosphorus(PP),total dissolved phosphorus(TDP)and dissolved reactive phosphorus(DRP)in paddy field runoff decreased with time,especially PP.Phosphorus concentration exceeded critical value and resulted to eutrophication,which threatened the water quality security of Chagan Lake.Phosphorus concentration in water recession canal increased with time,and eutrophication with different degrees appeared under high temperature.TP concentration in surface water of paddy field was highly negatively correlated with that in water recession canal,and the correlation coefficients R2(α=0.05)in three paddy fields were 0.8509,0.8964 and 0.9153,respectively.The pollution load of phosphorus in paddy field with the best irrigation condition was higher,and its pollution risk was the highest.Thus,such fields should be monitored and controlled mainly as the critical source area of phosphorus loss.[Conclusion]The study could provide theoretical foundations for developing saline land rationally,establishing optimal management measure of phosphorus in saline land and controlling phosphorus loss from farmland to protect local water resources. 展开更多
关键词 Saline soil PHOSPHORUS Dynamic variation characteristics potential environmental effect China
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Soil Environmental Index For Slovak Agricultural Land
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作者 J.VILCEK R.BUJNOVSKY 《Pedosphere》 SCIE CAS CSCD 2014年第1期137-144,共8页
The soil environmental index(SEI),which is a four digit code system,represents relatively homogenous spatial unit with specific soil capacity to provide ecological or non-production functions.This work aimed to presen... The soil environmental index(SEI),which is a four digit code system,represents relatively homogenous spatial unit with specific soil capacity to provide ecological or non-production functions.This work aimed to present information on rating and economic evaluation of SEI,which is a spatial identifier used for expressing heterogeneity of Slovak agricultural soil to support analysis of soil ecological functions.In this study,SEI index expressed the capacity of soil to accumulate water,immobilise the risk elements and substances and transform risk substances(organic pollutants).Partial evaluations of soil capacity to provide above mentioned functions were used to derive final SEI values.Within the agricultural soils of Slovakia there were 493 combinations of soil environmental index.Each index was expressed through rating(point)value and economic value.Average value of Slovak agricultural land to provide selected ecological soil functions was 55.3 points,which corresponded to 35.946 billionper agricultural land or approximately 1.42per square meter.Spatial identification of SEI codes and relevant database were developed in vector form via geographical information systems of Soil Science and Conservation Research Institute,Bratislava.In addition to using the national soil database system,a strategy was presented for evaluating and pricing of soil ecological function,and the development of an soil environmental index.Assessment and evaluation of vitally important soil functions expressed by SEI can significantly contribute to planning and protection of the soil,and can regulate indiscriminate anthropic interventions in land use decisions. 展开更多
关键词 ecological soil functions environmental potential soil evaluation
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Reactor Network Synthesis for Waste Reduction Using Instantaneous Value of Environmental Index 被引量:2
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作者 陈启石 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期155-158,共4页
Waste reduction is gaining importance as the preferred means of pollution prevention. Reactor network synthesis is one of the key parts of chemical process synthesis. In this study, a geometric approach to reactor net... Waste reduction is gaining importance as the preferred means of pollution prevention. Reactor network synthesis is one of the key parts of chemical process synthesis. In this study, a geometric approach to reactor network synthesis for waste reduction is presented. The bases of the approach are potential environment impact (PEI) rate-law expression, PEI balance and the instantaneous value of environmental indexes. The instantaneous value can be derived using the PEI balance, PEI rate-law expression and the environmental indexes. The optimal reactor networks with the minimum generation of potential environment impact are geometrically derived by comparing with areas of the corresponding regions. From the case study involving complex reactions, the approach does not involve solving the complicated mathematical problem and can avoid the dimension limitation in the attainable region approach. 展开更多
关键词 instantaneous value of environmental indexes reactor network synthesis potential environmental impact waste reduction
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Development of Reaction Process with the Consideration of Environmental Impact Minimization
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作者 陈启石 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期611-615,共5页
A methodology is presented to identify environmental impact minimization alternatives for reaction processes and assess their environmental performance. The potential environmental impact (PEI) scheme can be used to v... A methodology is presented to identify environmental impact minimization alternatives for reaction processes and assess their environmental performance. The potential environmental impact (PEI) scheme can be used to visibly display the transformation relationships among different types of PEI, identify the sources of environmental impacts, and propose alternatives for eliminating or minimizing the impacts. To evaluate the environmental performance of the alternatives effectively, some new indices, such as PEI input rate of non-products, PEI output rate of non-products per profit and the PEI conversion efficiency are proposed. Finally, the application of the methodology is illustrated using an industrial case study. 展开更多
关键词 potential environmental impact scheme development of chemical process environmental protection
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Environmental Integration of Small Hydropower Development
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作者 ZHAO Jianda 《Small Hydro Power News》 2006年第2期6-14,共9页
On the basis of cooperative research with European professionals, problems relating to environmental and ecological protection were discussed while small hydropower development in China currently was introduced in thi... On the basis of cooperative research with European professionals, problems relating to environmental and ecological protection were discussed while small hydropower development in China currently was introduced in this paper. Guidelines of small hydropower development dealing with environmental protection were sug- gested hereby. Various specific technical environmental solutions focusing on small hydropower development applied in European and other developed countries were also introduced in this paper. Main environmental solutions are discussed as follows: integrated design should be advocated during plan/design stage," ecohydraulic engineering and its utilization in SHP design and construction; effective technical approaches to relieve and eliminate the impact of river interception and fix the reasonable minimum biological flow; environment-friendly mitigation and compensation measures for high/low-head hydropower schemes applied in diversion works, intake, nature-like fish-passes, penstock and powerhouse design; study and application of the new technology, material and equipments; launching renovation of environmental protection in existing stations; emphasiz- ing public participation and their acceptability for the SHP environment; coordinated inter-disciplinary study at national level, etc. Two case studies in Sweden and Australia are given here. 展开更多
关键词 Small hydropower Hydropower potential with environmental constraints Entironment environmental integration Integrated design Minimum biological flow Nature-like fish-passes Solution European China Case study
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Tapping the Market Potential by Improving China's Investment Environment——An Analysis on Foreign Trade Situation
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《China's Foreign Trade》 2002年第9期7-10,共4页
关键词 this over Tapping the Market potential by Improving China’s Investment Environment An Analysis on Foreign Trade Situation WTO
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