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Establishing environmental background values of selected trace elements and environmental quality assessment of fi negrained sediments in the Jiaozhou Bay catchment,China
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作者 Fangjian XU Xu TIAN +2 位作者 Xianchao WANG Xiaoming WAN Bo CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1444-1453,共10页
With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained... With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained sediment samples from the Jiaozhou Bay catchment were selected to evaluate their 2015 environmental background values and the environmental quality.Using statistical analysis,the environmental background values(ranges)of Sc,Co,Ni,Cu,Pb,Zn,Cd,and Cr were calculated,being 13.1(10.8-15.4),12.4(8.6-16.2),32.0(22.9-41.2),29.6(13.5-64.9),24.1(13.0-44.6),77.6(38.5-156.5),0.07(0.02-0.20),and 82.5(66.5-104.0)mg/kg,respectively.The enrichment factor,contamination factor,and pollution load index were used to evaluate the pollution status of the Jiaozhou Bay catchment.The environmental background values of most elements are higher than those of the upper continental crust and lower than those of global shale.At present,the pollution in the eastern Jiaozhou Bay is much higher than that in the western part.The results shall be helpful for future management for trace element pollution monitoring in the Jiaozhou Bay catchment. 展开更多
关键词 SEDIMENTS environmental background values environmental assessment CONTAMINATION Jiaozhou Bay
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ASSESSMENT ON THE COMMONWEAL VALUES OF WETLANDS 被引量:2
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作者 Li-juan Cui Li-li Pan Yan-bo Zhang 《Chinese Geographical Science》 SCIE CSCD 2000年第4期84-89,共6页
Assessment on wetland values is being payed more and more attention by researchers, administrators and public. This question is related to human’s sustainable development in biosphere. This article analyses the commo... Assessment on wetland values is being payed more and more attention by researchers, administrators and public. This question is related to human’s sustainable development in biosphere. This article analyses the commonweal values of wetlands and establishes an index system by Analytical Hierarchy Process, then assigns quantitatively the system through calculating matrix eigenvalue and characteristic vector, at last, sets up an integral way of commonweal value assessment .This paper takes Zhalong Wetland and Xianghai Wetland as study cases , the assessment results show that the both wetlands belong to the first grade importance protective wetland, which validates the method’s practicability , scientific nature and rationality. 展开更多
关键词 WETLANDS commonweal valueS assessment CASE STUDY
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The application of fair value in the non-monetary assets transaction
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作者 QIN Jiahui 《International English Education Research》 2016年第7期76-78,共3页
Since issued new accounting standards for enterprises in our country, our country the non-monetary assets transaction is using fair value measurement. In the fair value measurement has advantages and disadvantages. Su... Since issued new accounting standards for enterprises in our country, our country the non-monetary assets transaction is using fair value measurement. In the fair value measurement has advantages and disadvantages. Such as can response the present value of enterprise assets, improve the relevance of accounting information. But it also has some problems. Based on the application of fair value in the non-monetary assets exchange, analysis on the problems existing in the practical application, and proposes the corresponding countermeasures and Suggestions. 展开更多
关键词 Fair value the Non-monetary assets transaction PROBLEMS Suggestions
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A Preliminary Exploration of the Functional Value Assessment of Ecosystem Services in Aral City
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作者 Guona Luo Xiancan Li +2 位作者 Shuang Liu Muhang Li Shuya Zhang 《Journal of Atmospheric Science Research》 2022年第1期18-24,共7页
Using the principles and methods of eco-economics as the research object,Aral City comprehensively expounds the ecological service functions such as ecosystem regulation of climate,carbon sequestration,soil conservati... Using the principles and methods of eco-economics as the research object,Aral City comprehensively expounds the ecological service functions such as ecosystem regulation of climate,carbon sequestration,soil conservation,water conservation and purification environment,and evaluates its economic value.The total value of the estimated 2021 is 1303.65 million yuan.At the same time,the importance of ecological service functions of urban ecosystems,from large to small,is to sequester carbon and release oxygen,purify the environment,maintain soil,conserd water sources,regulate the climate.The ecosystem service function which needs to be paid attention to in the concept of ecological construction and restoration of the next stage of ecological construction in Aral City. 展开更多
关键词 City of Aral Ecosystem services function Economic value assessment
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Value Assessment of the Lake Hpnghu Wetland and Protection of Its Biodiversity
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作者 Wang Xuelei & Du Yun(Institute of Geodesy & Geophysics, CAS) 《Bulletin of the Chinese Academy of Sciences》 2002年第3期157-162,共6页
A wetland ecosystem's value may be considered as the value derived from its natural resources, the value derived from its eco-environment, the value for special protection and values in cultural, research and educ... A wetland ecosystem's value may be considered as the value derived from its natural resources, the value derived from its eco-environment, the value for special protection and values in cultural, research and educational aspects. Lake Honghu, in the heartland of Hubei Province, covers a vast but shallow body of water and surrounding marshlands. It is conducive to farmland irrigation, flooding regulation, adjustment of the local climate and self-purification of the water quality. Because of its benign functions, the native ecosystem of the lake is ecologically sound, and the thriving wildlife in its ecosystem makes it a primordial pool of biodiversity. Besides, it is possible to transform it into a national base for environmental education and an R&D center for freshwater organisms, so that it can play a constructive role in heightening the public's awareness of environmental protection. 展开更多
关键词 AS value assessment of the Lake Honghu Wetland and Protection of Its Biodiversity LAKE
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Ecosystem Service Value Assessment of Wutong Mountain Rhododendron moulmainense Ecological Landscape Forest in Shenzhen City in 2021
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作者 Rui CONG Kaiwen ZHANG +1 位作者 Xiaodan CHEN Dingyue WANG 《Agricultural Biotechnology》 CAS 2023年第4期88-92,共5页
Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accoun... Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accounting method.The assessment results showed that the total ecosystem service value of R.moulmainense ecological landscape forest was 13.195 billion yuan,and the top three services included the value of forestry products,the value of biodiversity maintenance and the value of leisure and recreation,indicating that the ecosystem service of Wutong Mountain R.moulmainense ecological landscape forest in Shenzhen has great ecological and economic value,especially in forestry products,biodiversity maintenance,and leisure and recreation. 展开更多
关键词 Wutong Mountain Rhododendron moulmainense Ecological landscape forest Ecosystem services value assessment
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Modelling the Financial Value of the Maroochy River to Property Values: An Application of Neural Networks 被引量:1
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作者 Andrew HIGGINS Leonie PEARSON Luis LAREDO 《Journal of Water Resource and Protection》 2009年第4期237-248,共12页
The Maroochy River, which is located on east coast of Australia, provides a variety of uses and values to the community. Changes in structure, function and management of the river will influence the value that the com... The Maroochy River, which is located on east coast of Australia, provides a variety of uses and values to the community. Changes in structure, function and management of the river will influence the value that the community derives from it. Therefore, critical to the river’s continued management is the development of policy relevant tools based on the community’s value of the river. This paper focuses on estimating the fi-nancial value the local residents derive from living close to the river through investigation of changes in residential property values due to attributes of the Maroochy River. It is a complex analysis since there are several confounding geographical and property variables. Given a large and complete dataset of 28,000 properties for the Maroochy region, Artificial Neural Networks (ANN) was applied to estimate the economic value of the properties. This ANN was then able to simulate scenarios for property values with respect to changes in environmental features. It showed the Maroochy River contributed AU$900,000,000 to the unim-proved capital value of the whole region, a value that could not be estimated previously, and much higher than anticipated. Calculating potential annual payments to the Shire Council through land tax analysis from these property values, provides the council with means to justify expenditure to maintain a standard of water quality and ecosystem health. 展开更多
关键词 NATURAL ASSET FINANCIAL value NEURAL Network
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Land Use Change and Its Impact on Values of Ecosystem Services in the West of Jilin Province 被引量:1
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作者 LU Yuan WANG Juan +1 位作者 WEI Liangying MO Jianfei 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1028-1034,共7页
According to interpreting the LANDSAT TM/ETM images of 1986 and 2002, the spatial-temporal characteristics of land use changes were analyzed during 16 years base on GIS. In addition, the change of ecosystem services d... According to interpreting the LANDSAT TM/ETM images of 1986 and 2002, the spatial-temporal characteristics of land use changes were analyzed during 16 years base on GIS. In addition, the change of ecosystem services due to land use change was estimated by the method of vaulting global ecosystem services. The result shows that there were rapid increases in the area of cropland, saline-alkaline land, and dramatic decreases in grassland, water area and wetland between 1986 and 2002. The annual value of the ecosystem services was declined from 767.1 ×10s Yuan/a in 1986 to 624.1 × 10s Yuan/a in 2002, the estimated annual ecosystem service value declined by 18. 6 % (i. e. 1.6% per year) between 1986 and 2002. It indicates that there had been a sever harm to ecosystem functions and services, which results from the deterioration of ecological environment and the adjustment of land use that aim to currently economic benefit. 展开更多
关键词 land use change ecosystem services ecological values impact assessment
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Arsenic in Drinking Water Toxicological Risk Assessment in the North Region of Burkina Faso 被引量:1
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作者 Jean Fidèle Nzihou Médard Bouda +1 位作者 Salou Hamidou Jean Diarra 《Journal of Water Resource and Protection》 2013年第8期46-52,共7页
Human health risks assessment were estimated by determining the nature and probability of adverse health effects in the North region’s populations who are now exposed to arsenic from drinking water or will be exposed... Human health risks assessment were estimated by determining the nature and probability of adverse health effects in the North region’s populations who are now exposed to arsenic from drinking water or will be exposed in the future. Several questions were addressed in this study: what types of health problems may be caused by arsenic from drinking water? What is the chance that people will experience health problems when exposed to different levels of arsenic? What arsenic level are people exposed to and for how long? To answers these questions we have first identified the hazard by evaluating arsenic concentration in thirty-four (34) bore-hole water points among the region based on the assumption of clinical cases related to drinking water. Arsenic concentration ranged from 0 up to 87.8 micrograms per liter. Next we assessed the dose-response of exposure to arsenic. Dose-response relationship describes how the likelihood and severity of adverse health effects are related to the amount and condition of exposure to arsenic. This required us to choose toxicity reference values (TRVs) above which adverse effects may occur for noncarcinogenic and for carcinogenic effects. Exposure factors have been calculated in two scenarios: people from 0 to 14 years old and people from 15 to 70 years. Exposure has been estimated indirectly through consideration of measured concentrations of arsenic in drinking water. This study show that people in the Yatenga, Zondoma and Passore provinces are at very high risk for developing several pathologies such as hyper pigmentation, keratosis, cancer, etc. due by chronic exposure to arsenic in drinking water. 展开更多
关键词 ARSENIC POISONING TOXICITY Reference value Risk assessment CARCINOGENIC Effect EXPOSURE Factor
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Modeling dynamic assessment of ecosystem services based on remote sensing technology:A sampling of the Gansu grassland ecosystem 被引量:1
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作者 Jian Wang ZhengHua Chen 《Research in Cold and Arid Regions》 2010年第6期514-521,共8页
The ecosystem is important because it is the life sustaining system for human survival.Three ecosystem characteristics are:regional particularities,ecosystem complexity and conventional cultural particularities.This p... The ecosystem is important because it is the life sustaining system for human survival.Three ecosystem characteristics are:regional particularities,ecosystem complexity and conventional cultural particularities.This paper develops a remote sensing based dynamic model to assess grassland ecosystem service values involving multidisciplinary knowledge.The ecological value of grassland ecosystems is focused on using a remote sensing technique in the model,and setting up the framework for a dynamic assessing model.The grassland ecological services condition and value in 1985 is used as the benchmark.The dynamic model has two adjusting indicators:biomass and price index.The biomass is simulated using the CASA(Carnegie-Ames-Stanford Approach) model.The price index was obtained from statistics data published by the statistical bureau.Results show that the grassland ecosystem value in Gansu Province was 28.36 billion Chinese Yuan in 1985,140.37 billion in 1999 and 130.86 billion in 2002. 展开更多
关键词 ecosystem services value dynamic assessing model remote sensing CASA BIOMASS price index
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Does the EVA valuation model explain the market value of equity better under changing required return than constant required return? 被引量:3
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作者 Sujata Behera 《Financial Innovation》 2020年第1期149-172,共24页
Through the Economic-Value-Added(EVA)valuation model,the expected market value of equity can be determined by adding the book value of equity with the present value of expected EVAs under the assumption of constant re... Through the Economic-Value-Added(EVA)valuation model,the expected market value of equity can be determined by adding the book value of equity with the present value of expected EVAs under the assumption of constant required return and constant return on equity.The equation of EVA valuation model has taken its shape under the assumption of constant required return and constant return on equity.However,a large body of empirical evidence indicates that required rate of return never remain constant.The EVA-valuation model formulated under constant required return cannot be implemented under the scenario of changing required return.In this study,we explored whether the EVA valuation model could be implemented under changing required return by making any changes in the model and found that it could be implemented under the scenario of changing required return by replacing the book value of the equity of the existing model with the present value of required earnings or normal market earnings.We further examined whether the explanatory ability of the EVA valuation model under the assumption of changing required return is better than that of the valuation model under the assumption of constant required return.Relative information content analyses were conducted by considering sample of the intrinsic value of equities determined by valuation models and the market value of equities of 69 large-cap,88 mid-cap,and 79 small-cap companies.The results showed that the EVA-based valuation model with changing normal market return outperformed the EVA-based valuation model with constant required return. 展开更多
关键词 Economic value added(EVA) Capital asset pricing model(CAPM) Expected market value of equity under constant required return(EMVEUCRR) Expected market value of equity under varying required return(EMVEUVRR)
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The Impact of Carbon Emissions on Asset Values and Operating Cash Flows: Evidence From Australian Listed Companies
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作者 Li Yongqing Ian Eddie Liu Jinghui 《Journal of Modern Accounting and Auditing》 2013年第1期94-111,共18页
In November 2011, the Australian government approved the legislation (Clean Energy Act 2011) to introduce a reduction plan of carbon emissions in Australia. This plan will be implemented from July 2012. This is one ... In November 2011, the Australian government approved the legislation (Clean Energy Act 2011) to introduce a reduction plan of carbon emissions in Australia. This plan will be implemented from July 2012. This is one of the first accounting studies to investigate the potential impacts of this plan on long-lived asset values and operating cash flows for Australian listed companies. A sample of Australian Securities Exchange (ASX) 200 indexed companies from 2'006 to 2010 is used. Hypotheses are tested based on Heckman's (1979) two-stage approach. Three regression models are developed to examine the association between carbon emissions and asset values/operating cash flows. This study finds that asset values and operating cash flows will be adversely affected, if the reduction plan is implemented. Specifically, this study finds that the book value of long-lived assets will decrease, if listed companies are considered to be emissions-liable. The book value of long-lived assets is further found to be negatively associated with listed companies' carbon emission levels. This study also demonstrates that operating cash flows of emissions-liable companies will be adversely affected. However, this study does not find a relationship between operating cash flows and companies' emission levels. The empirical findings from Australian listed companies provide the evidence that the reduction plan of carbon emissions will adversely affect corporate entities' asset values and operating cash flows. The results further indicate that the magnitude of the impact will be proportional to the companies' emission levels. The implications of these empirical findings for listed companies, for the accounting profession, and for carbon emission regulators are also discussed. 展开更多
关键词 carbon emissions reduction asset values operating cash flows AUSTRALIA
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Tangible Assets Threats and Hazards: Risk Assessment and Management in the Port Domain
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作者 Constantinos I. Chlomoudis Petros L. Pallis Ernestos S. Tzannatos 《Journal of Traffic and Transportation Engineering》 2017年第5期271-278,共8页
Port systems are more prone to being risk oriented. Many specific methods have been found to assess risk in a port area or operation. A review is presented in different approaches on human and environmental risks in p... Port systems are more prone to being risk oriented. Many specific methods have been found to assess risk in a port area or operation. A review is presented in different approaches on human and environmental risks in port area. On the other hand, there is no specific risk management method or fi'amework to cope with threats and hazards regarding on port machines or material accidents and port assets damages or losses. This paper presents a risk management methodology, seeking to investigate a process of assessing the assets hazards and damages into the domain of port container terminal, by taking into account its different factors and their mutual influences. This methodology constitutes a decision support framework that will be used to conduct port to port risk evaluations or to assess a whole port's and terminal's risk level in the critical field of assets damages and losses, in order to facilitate improvement strategies. An empirical study is contacted for the years of 2003-2012, in order to provide evidence for risk assessment and management in an economic effective way, regarding port assets damages and losses, at the Port Container Terminal of Piraeus in Greece. 展开更多
关键词 assets PORT RISK assessment MANAGEMENT Greece.
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The Prediction Analysis of Customer Lifetime Value in Business to Business Enterprise
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作者 Cheng Ai-wu Chao Cheng Wang Xiu 《Journalism and Mass Communication》 2013年第12期820-828,共9页
The measurement of customer assets value has become a significant task in the field of marketing. Although a series of achievements have been formed, the deeper research is still needed in the following aspects: how ... The measurement of customer assets value has become a significant task in the field of marketing. Although a series of achievements have been formed, the deeper research is still needed in the following aspects: how to build parameter estimation model of various variables based on the interaction among customer assets elements and how to get the scientific and available measured data. In order to solve these problems, this paper, based on the characteristics of customer relationship in Business to Business (B to B) enterprise and the analysis of the variable factors in the interactive models will systematically and practically use the seemingly unrelated regression method to construct three main parameters estimation models in the customer assets measurement model, and prove the feasibility of the model through a case study. Research results show that measurement model system constructed by this method solves the problem of interaction and germination among parameters influencing factors. At the same time, factors concentration simplifies data sources to ensure the reliability and objectivity of the data, and thus improve the accuracy and feasibility of the estimation of customer assets value. 展开更多
关键词 customer assets value MEASUREMENT Businese to Businese (B to B) the seemingly unrelated regression
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Assessment of Ecosystem Services Value in Hotan Oasis, Xingjiang 被引量:3
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作者 杨依天 王平 +2 位作者 黄宇 张月从 郭翠恩 《Agricultural Science & Technology》 CAS 2013年第3期425-432,共8页
[Objective] The study aimed to assess the ecosystem services value in Hotan Oasis, Xingjiang. [Method] The visual interpretation method was adopted to process TM/ETM+ images based on field investigation in Hotan Oasi... [Objective] The study aimed to assess the ecosystem services value in Hotan Oasis, Xingjiang. [Method] The visual interpretation method was adopted to process TM/ETM+ images based on field investigation in Hotan Oasis. These inter- pretation data, along with two periods of land use data, were reclassified to farm- land, forest, grassland and so on. Then, the ecosystem services value was calculat- ed and analyzed. [Result] Analysis indicated that the ecosystem services value had been increased by 30.44x108 Yuan (16.51%) in the study area during 1980-2010, which can be explained by the increase of glacier and snowfield distributed in the south mountain with the increase of annual precipitation. At the same time, the con- tribution rate of grassland to ecosystem services value had been decreased as a result of degradation of grassland and occupation from farmland. For the whole basin, the increase of ecosystem services value came from the upper reaches, while the ecosystem services value had been reduced in the middle and lower reaches. In the middle reaches, the reduction came mainly from wetland (-1.83x10s Yuan), waters (-1.68x10s Yuan), forest (-0.86x108 Yuan) and grassland (-0.80x108 Yuan). But in the lower reaches, the ecosystem services values of waters, grassland and forest were -0.61 x108 Yuan, -0.24x108 Yuan, and -0.07x10s Yuan, respectively. [Conclusion] If some effective policies, such as the implementation of returning farm- land to forest and ceasing from farming to grazing, would be taken, the ecosystem degradation can be constrained and reversed in the northwest arid region. 展开更多
关键词 Arid region Ecosystem services value assessment Hotan Oasis
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Assessment of Direct Eco-value of Liangzi Lake
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作者 封瑛 李兆华 刘化吉 《Agricultural Science & Technology》 CAS 2013年第6期882-885,共4页
[Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environm... [Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environment was introduced and the productivity of the lake was investigated both through the literature materials and the investigations. The market value method was clarified in this paper as well as its operation process and the application fields. [Result] Based on the introduction of the current situation in Liangzi Lake, the direct usage value was estimated as 1.32 billion Yuan/year. Plant resources value was 318 million Yuan/year; animal resources value was 675 million Yuan/year; and water storage value was 325 million Yuan/year for the three parts. [Conclusion] This paper will attract more attention to the emphasis of the reasonable development of nature sources. 展开更多
关键词 Valuation assessment Direct usage value Market value method Liangzi Lake
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Correction of Corporation Value Assessment Model Based on Corporate Social Responsibility
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作者 贠晓兰 《Agricultural Science & Technology》 CAS 2017年第4期736-739,共4页
The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate a... The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate and check the costs and benefits brought by the implementation of corporate social responsibility under the current ac- counting theory system, so it is difficult to estimate whether the fulfillment of corpo- rate social responsibility has any effects on the corporation value assessment. Therefore, based on corporate social responsibility, the correction mode of corpora- tion value assessment is put forward. 展开更多
关键词 Corporation value Social responsibility assessment model Correction model
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Nutrients distribution and trophic status assessment in the northern Beibu Gulf, China 被引量:17
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作者 赖俊翔 姜发军 +3 位作者 柯珂 许铭本 雷富 陈波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1128-1144,共17页
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat... Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf. 展开更多
关键词 nutrient EUTROPHICATION Trophic index (TRIX) assessment of Estuarine Trophic Status(assets Beibu Gulf Guangxi Province
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Empirical Analysis of Forest Landscape Value Assessment:A Case Study of Huangshui Forest Park in Xining,Qinghai Province 被引量:2
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作者 MA Shengde WANG Jianfeng 《Journal of Landscape Research》 2013年第6期27-28,共2页
Questionnaire survey and CVM were adopted to evaluate economic value of Huangshui Forest Park in Xining,Qinghai.Value of its forest landscapes was assessed,multiple linear regression was established to analyze correla... Questionnaire survey and CVM were adopted to evaluate economic value of Huangshui Forest Park in Xining,Qinghai.Value of its forest landscapes was assessed,multiple linear regression was established to analyze correlation between factors related to willingness-to-pay(WTP). 展开更多
关键词 LANDSCAPE value assessment WILLINGNESS-TO-PAY Huangshui FOREST PARK
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Resources of Colored-leaf Trees and Their Phenological Ornamental Characteristics in Lhasa City 被引量:2
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作者 LIU Zhineng ZHOU Peng XU Jin 《Journal of Landscape Research》 2017年第1期30-36,共7页
By using biological five points,expert consultation and fuzzy comprehensive evaluation,the species,phenological ornamental characteristics,and landscape application of colored-leaf trees in Lhasa City were surveyed sy... By using biological five points,expert consultation and fuzzy comprehensive evaluation,the species,phenological ornamental characteristics,and landscape application of colored-leaf trees in Lhasa City were surveyed systematically. The results show that there are 42 species of colored-leaf trees in Lhasa City,belonging to 31 genera and 18 families,of which there are 5,19,and 18 species of spring,autumn,and common colored-leaf trees,accounting for 11.90%,45.24% and 42.86% of total number of the investigated tree species respectively. It is clearly seen that there are too few species of spring colored-leaf trees in the city. There are 19 and 17 species of trees possessing red and yellow leaves,while the leaves of other 6 species of colored-leaf trees are shown in other colors,and the number of their species accounts for 45.24%,40.48% and 14.28% of total number of the investigated tree species respectively. The best ornamental periods of spring,autumn and common colored-leaf trees in Lhasa City average 38.4,41.8 and 251.8 d respectively. Prunus cerasifera Ehrhar f. atropurpurea Rehd.,Ulmus pumila L.,Populus × beijingensis W. Y. Hsu,and Salix alba are applied most frequently in Lhasa City,and their relative frequency is 18.67%,10.29%,9.91% and 8.95% respectively. According to the comprehensive assessment value of their ornamental characteristics,the ornamental characteristics of 15 species of colored-leaf trees in Lhasa City are good or very good,and there is a positive correlation between the comprehensive assessment value and relative frequency. Based on the investigation,the current application situation and problems of colored-leaf trees in Lhasa City were analyzed,and solutions to the problems were proposed. 展开更多
关键词 TIBET Lhasa City Colored-leaf trees PHENOLOGY Ornamental period Comprehensive assessment value Frequency
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