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The Economics of Competing Water Uses under a FERC Licensing Agreement: Estimation of Property Value, Recreation, and Hydroelectric Impacts
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作者 Matthew Bingham Jason Kinnell 《Journal of Water Resource and Protection》 CAS 2024年第6期414-428,共15页
Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider t... Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider the integrated suite of values and tradeoffs that attend changes in water uses and availability. Section 316 (b) of the Clean Water Act requires that owners of certain water cooled power plants evaluate technologies and operational measures that can reduce their impacts to aquatic organisms. The studies must discuss the social costs and benefits of alternative technologies including cooling towers (79 Fed. Reg. 158, 48300 - 48439). Cooling towers achieve their effect through evaporation. This manuscript estimates the property value, recreation, and hydroelectric generation impacts that could result from the evaporative water loss associated with installing cooling towers at the McGuire Nuclear Generating Station (McGuire) located on Lake Norman, North Carolina. Although this study specifically evaluates the effects of evaporative water loss from cooling towers, its methods are applicable to estimating the economic benefits and costs of a new water user or reduced water input in any complex reservoir system that supports steam electric generation, hydroelectric generation, residential properties, recreation, irrigation, and municipal water use. 展开更多
关键词 Property value FERC Hydroelectric RECREATION Water Levels
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Water Quality,Influential Factors,and Management Strategies from 2016 to 2020 in the Yangtze River Economic Belt,China
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作者 LIN Lanyu GUO Congrong +6 位作者 CHEN Yanan HE Lihuan YAN Luyu FANG Dekun MA Guangwen ZHANG Fengying LI Mingsheng 《Chinese Geographical Science》 2025年第1期175-186,共12页
The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could h... The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could help improve aquatic environment management in the YREB and our understanding of the causes and effects of water quality variations in other large river basins.In this study,river water quality,factors affecting water quality,and management strategies,and correlations between water quality indices and socioeconomic indicators in the YREB during the 13th Five-Year Plan period(2016-2020)were assessed.The single-factor evaluation method,constant price for GDP,and correlation analyses were adopted.The results showed that:1)water quality in the YREB improved during the 13th Five-Year Plan period.The number of aquatic environment sections meeting GradeⅠ-Ⅲwater quality standards increased by 13.1%and the number below Grade V decreased by 2.9%.2)The values of 12 indicators in the YREB exceeded relevant standards.The indicators with highest concentreation were the total phosphorus,chemical oxygen demand,ammonia nitrogen,and permanganate index,which were relatively high in downstream regions in Anhui Province,Jiangsu Province,and Shanghai Municipality.3)Ammonia nitrogen,chemical oxygen demand,and total phosphorus emissions per unit area and water extraction per unit area are relatively high in the three downstream regions mentioned above.4)Increased domestic sewage discharges have increased total wastewater discharges in the YREB.5)River water quality in the YREB strongly correlated with population,economic,and water resource indices and less strongly correlated with government investment,agriculture,meteorology,energy,and forestry indices.This confirmed the need to decrease wastewater discharges and non-point-source pollutant emissions.The aquatic environment could be improved by taking reasonable measures to control population growth,adjusting the industrial structure to accelerate industrial transformation and increase the proportion of tertiary industries,and investing in technological innovations to protect the environment. 展开更多
关键词 water quality FACTORS coping strategies Yangtze River economic belt(YREB) China
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Impact of Land Use Change on Ecosystem Services Values in Danjiangkou Reservoir Area,China in the Context of National Water Network Project Construction
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作者 LIU Linghua ZHENG Liang +3 位作者 WANG Ying LIU Chongchong ZHANG Bowen BI Yuzhe 《Chinese Geographical Science》 2025年第1期111-130,共20页
Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the nationa... Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the national water network and guaranteeing regional ecological stability.Using the Danjiangkou Reservoir Area(DRA),China as the study area,this paper first examined the spatiotemporal dynamics of natural landscape patterns and ecosystem service values(ESV)in the DRA from 2000 to 2018 and then investigated the spatial clustering characteristics of the ESV using spatial statistical analysis tools.Finally,the patch-generating land use simulation(PLUS)model was used to simulate the natural landscape and future changes in the ESV of the DRA from 2018 to 2028 under four different development scenarios:business as usual(BAU),economic development(ED),ecological protection(EP),and shoreline protection(SP).The results show that:during 2000-2018,the construction of water facilities had a significant impact on regional land use/land cover(LULC)change,with a 24830 ha increase in watershed area.ESV exhibited an increasing trend,with a significant and growing spatial clustering effect.The transformation of farmland to water bodies led to accelerated ESV growth,while the transformation of forest land to farmland led to a decrease in the ESV.Normalized difference vegetation index(NDVI)had the strongest effect on the ESV.ESV exhibited a continuous increase from 2018 to 2028 under all the simulation scenarios.The EP scenario had the greatest increase in ESV,while the ED scenario had the smallest increase.The findings suggest that projected land use patterns under different scenarios have varied impacts on ecosystem services(ESs)and that the management and planning of the DRA should balance social,economic,ecological,and security benefits.nomic,ecological,and security benefits. 展开更多
关键词 ecosystem services value(ESV) national water network project of China South-to-North Water Diversion Project(SNWDP)of China multi-scenario simulation Danjiangkou Reservoir Area China
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Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L. 被引量:6
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作者 高建芹 浦惠明 +4 位作者 张洁夫 龙卫华 陈锋 周晓婴 张维 《Agricultural Science & Technology》 CAS 2013年第10期1421-1428,共8页
[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish reg... [Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions. 展开更多
关键词 Brassica napus L. SPAD value Chlorophyll content economic yield Correlation analysis
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基于Valued ERGMs模型的核心技术网络成长机制研究——以量子计算领域为例 被引量:2
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作者 任海英 李真 《科技进步与对策》 CSSCI 北大核心 2024年第4期1-11,共11页
对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关... 对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关系为基础的量子计算领域核心技术网络,并基于Valued ERGMs模型构建核心技术网络成长机制模型。结果表明,技术要素中心性、专利技术研发能力、与TRIZ进化法则匹配程度以及技术要素同配性对核心技术网络成长具有正向促进作用;在技术路径方面,核心技术网络成长受到技术要素路径依赖性和技术突破的双重影响。最后,根据量子计算领域核心技术网络成长机制的实证研究结果,从技术研发层面、企业层面、政府层面为相关领域技术发展提出策略建议。 展开更多
关键词 技术演化 核心技术网络 技术网络成长机制 valued ERGMs模型 量子计算
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弹性退休制度下谁更愿意延迟退休?——基于Option Value模型的微观模拟
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作者 郭秀云 李悦心 《人口与发展》 CSSCI 北大核心 2024年第4期132-144,共13页
人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、... 人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、内部报酬率进行模拟。研究发现:养老金总财富随退休年龄“先增后减”,男性的峰值年龄早于女性;引入养老金“奖惩”机制有助于提高最优退休年龄,激励劳动者延迟退休;考虑闲暇偏好的异质性,男性参保者更倾向于早退休,而女性参保者特别是女性较高收入群体更愿意延迟退休;厌恶风险的参保者更有可能选择早退休。建议尽早建立弹性退休年龄政策体系,增加劳动者的选择权和制度灵活性;引入精算调节因子构建养老金奖惩机制,完善养老保险待遇计发办法。 展开更多
关键词 延迟退休 养老金财富 Option value模型
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Economic Value Evaluation of Wetland Service in Yeyahu Wetland Nature Reserve,Beijing 被引量:9
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作者 ZHU Lin CHEN Yun +3 位作者 GONG Huili JIANG Weiguo ZHAO Wenji XIAO Yanfang 《Chinese Geographical Science》 SCIE CSCD 2011年第6期744-752,共9页
Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-... Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-provement,biodiversity maintenance,erosion control,water supply,recreational opportunity,raw material supply and existence value.Multiple conventional evaluation methods were used to calculate the value of eight wetland services.The results showed that significant values came from biodiversity maintenance and recreational opportunity.The main reasons were as follows.Firstly,Yeyahu Wetland Nature Reserve was the habitat for migrant birds,and government had payed more efforts to protect precious birds.Secondly,the population is large in Beijing.People enjoyed going outside and enjoyed the natural and artificial wetland scenes.At the same time,most people were prepared to pay for wetland conservation.The decline of vegetation cover made the economic value of erosion control the lowest.While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower.The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. 展开更多
关键词 economic value evaluation wetland service Yeyahu Wetland Nature Reserve BEIJING
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REE characteristics of the coal in the Erlian Basin, Inner Mongolia, China, and its economic value 被引量:7
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作者 Shao-qing Huang Shu-zheng Ning +2 位作者 Jian-qiang Zhang Li Zhang Kang Liu 《China Geology》 2021年第2期256-265,共10页
The rare earth elements(REE)content of the coal in the Erlian Basin was determined by inductively coupled plasma mass spectrometry(ICP-MS),and it turns out that the REE content from different geological age shows a si... The rare earth elements(REE)content of the coal in the Erlian Basin was determined by inductively coupled plasma mass spectrometry(ICP-MS),and it turns out that the REE content from different geological age shows a significant difference:The REE content of the coal in the Jurassic Alatanheli Group is from 152.05×10^(−6) to 1416.21×10^(−6),with an average value of 397.31×10^(−6),and the relative concentration factor shows enriched;the REE content of the coal in Early Cretaceous Baiyanhua Group is from 20.65×10^(−6) to 102.53×10^(−6),the mean value is 49.06×10^(−6),and the relative concentration factor shows normally.The REE distribution patterns samples in Jurassic and Cretaceous shows the difference:The REE pattern in Jurassic coal mainly manifests as H-type distribution,with the Y,Lu positive anomaly,it is speculated that the fluid carried REE ions into the coal-bearing basin,and the heavy REE gather in the coal due to the different chemical properties of each REE.The REE occurrence mode is presumed to be mainly organic.Flat type is the REE main distribution pattern in Cretaceous coal.The REE patterns in clastic rocks of the roof,parting and floor of coal seam are similar to the REE patterns in the coal and the most possible reason is that the REE main source is from the clastic rock.It showed that the coal of the Early Jurassic,especially of Amugulen coalfield has resource value. 展开更多
关键词 Rare earth elements(REE) Distribution pattern type Concentration factor Alatanheli Group Baiyanhua Group economic value Erlian Basin Inner Mongolia China
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SCISSORS DIFFERENCE AND ITS IMPACTS ON ECONOMIC VALUE OF CULTIVATED LAND IN CHINA 被引量:1
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作者 WANG Xiu-fen CHEN Bai-ming BI Ji-ye 《Chinese Geographical Science》 SCIE CSCD 2005年第3期193-199,共7页
The problem of price scissors difference between industrial products and agricultural products is one of the important problems in China. It impacts not only the living standard improvement of farmers but also the eco... The problem of price scissors difference between industrial products and agricultural products is one of the important problems in China. It impacts not only the living standard improvement of farmers but also the economic value of cultivated land, furthermore results in the direct and indirect loss of cultivated land resources. China's cultivated land area has decreased dramatically in recent years. An important reason for the decrease is the relatively low cost of cultivated land occupancy, which results from the distortion of economic value of cultivated land due to the existence of scissors difference. This study firstly analyzed the dynamic change of scissors difference and calculated the absolute and relative magnitude of scissors difference from 1997 to 2002, then computed the economic value of cultivated land before and after scissors difference adjustment in 2002, and finally discussed the inverted scissors difference. Results suggest that the scissors difference has a remarkable impact on the economic value of cultivated land, and the adjustment of scissors difference even inverted scissors difference to the economic value of cultivated land is indisoensable. 展开更多
关键词 cultivated land economic value scissors difference scissors difference adjustment P. R. China
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Estimation of the Economic Value of Irrigation Water in Jordan 被引量:1
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《Journal of Agricultural Science and Technology(B)》 2012年第5期487-497,共11页
Insight into the different values of water is essential to support rational decision making about policies, management and investments in the water sector. The main objective of this paper is to estimate an economic v... Insight into the different values of water is essential to support rational decision making about policies, management and investments in the water sector. The main objective of this paper is to estimate an economic value of irrigation water in Jordan by choosing appropriate methodology fit with available data. The Residual Imputation Method (RIM) is used to determine the average economic value of irrigation water used in agriculture across crops. The results showed that the weighted average of water value used in field crops is JD 0.44 m"3 and JD 1.23 m3 for vegetable crops and JD 0.23 m3 for fruit trees. The overall weighted average water value in irrigation is estimated with JD 0.51 m"3. With regard to individual crops, cucumbers had the highest water values with about JD 6.05 m3, followed by string beans with JD 2.64 m3, and sweet pepper with JD 2.54 m3. The lowest returns per m3 were provided by squash, radish and hot pepper. For fruit tress banana has the highest water value JD 0.79 m3 and olive tress has the lowest with only JD 0.069 m3. The current practice of some banana producers is economically rational by installing Reverse Osmosis unit to irrigate banana, since water value is twice the desalination costs of one cubic meter. The estimated values represent the maximum price that farmers might be willing to pay for water under the current market conditions. Water subsidy distorts farmers' perception of water as a scarce and thus valuable resource. Low water prices are thus likely to engender excessive use. It is necessary to allow water prices to recover the real cost of water supply and to ensure financial sustainability of water utilities. 展开更多
关键词 economic value residual imputation irrigation water horticultural crops.
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Hepatitis C virus cure with direct acting antivirals: Clinical,economic, societal and patient value for China 被引量:5
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作者 Qing Xie Jian-Wei Xuan +4 位作者 Hong Tang Xiao-Guang Ye Peng Xu I-Heng Lee Shan-Lian Hu 《World Journal of Hepatology》 CAS 2019年第5期421-441,共21页
About 10 million people in China are infected with hepatitis C virus(HCV),with the seroprevalence of anti-HCV in the general population estimated at 0.6%.Delaying effective treatment of chronic hepatitis C(CHC)is asso... About 10 million people in China are infected with hepatitis C virus(HCV),with the seroprevalence of anti-HCV in the general population estimated at 0.6%.Delaying effective treatment of chronic hepatitis C(CHC)is associated with liver disease progression,cirrhosis,hepatocellular carcinoma,and liver-related mortality.The extrahepatic manifestations of CHC further add to the disease burden of patients.Managing CHC-related advanced liver diseases and systemic manifestations are costly for both the healthcare system and society.Loss of work productivity due to reduced well-being and quality of life in CHC patients further compounds the economic burden of the disease.Traditionally,pegylatedinterferon plus ribavirin(PR)was the standard of care.However,a substantial number of patients are ineligible for PR treatment,and only 40%–75%achieved sustained virologic response.Furthermore,PR is associated with impairment of patient-reported outcomes(PROs),high rates of adverse events,and poor adherence.With the advent of direct acting antivirals(DAAs),the treatment of CHC patients has been revolutionized.DAAs have broader eligible patient populations,higher efficacy,better PRO profiles,fewer adverse events,and better adherence rates,thereby making it possible to cure a large proportion of all CHC patients.This article aims to provide a comprehensive evaluation on the value of effective,curative hepatitis C treatment from the clinical,economic,societal,and patient experience perspectives,with a focus on recent data from China,supplemented with other Asian and international experiences where China data are not available. 展开更多
关键词 Hepatitis C value of CURE Sustained VIROLOGIC response End stage liver disease Prevention of transmission COST-EFFECTIVENESS Productivity Societal value Patient-reported outcomes
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Total Carbon Stock and Potential Carbon Sequestration Economic Value of Mukogodo Forest-Landscape Ecosystem in Drylands of Northern Kenya 被引量:1
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作者 Nereoh C. Leley David K. Langat +2 位作者 Abdalla K. Kisiwa Geoffry M. Maina Meshack O. Muga 《Open Journal of Forestry》 2022年第1期19-40,共22页
Carbon sequestration is one of the important ecosystem services provided by forested landscapes. Dry forests have high potential for carbon storage. However, their potential to store and sequester carbon is poorly und... Carbon sequestration is one of the important ecosystem services provided by forested landscapes. Dry forests have high potential for carbon storage. However, their potential to store and sequester carbon is poorly understood in Kenya. Moreover, past attempts to estimate carbon stock have ignored drylands ecosystem heterogeneity. This study assessed the potential of Mukogodo dryland forest-landscape in offsetting carbon dioxide through carbon sequestration and storage. Four carbon pools (above and below ground biomass, soil, dead wood and litter) were analyzed. A total of 51<span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">(400</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">m<sup>2</sup>) sample plots were established using stratified-random sampling technique to estimate biomass across six vegetation classes in three landscape types (forest reserve, ranches and conservancies) using nested-plot design. Above ground biomass was determined using generalized multispecies model with diameter at breast height, height and wood density as variables. Below ground, soil, litter and dead wood biomass;carbon stocks and carbon dioxide equivalents (CO<sub>2eq</sub>) were estimated using secondary information. The CO<sub>2eq</sub> was multiplied by current prices of carbon trade to compute carbon sequestration value. Mean ± SE of biomass and carbon was determined across vegetation and landscape types and mean differences tested by one-way Analysis of Variance. Mean biomass and carbon was about 79.15 ± 40.22</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TB</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha</span></span></span><span style="font-size:10px;"><span style="vertical-align:super;">-</span></span><span><span><span style="font-family:;" "=""><sup>1</sup> and 37.25 ± 18.89</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TC</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha<sup><span style="font-size:10px;">-</span>1</sup> respectively. Cumulative carbon stock was estimated at 682.08</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TC</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha<sup><span style="font-size:10px;">&#45;</span>1</sup>;forest reserve (251.57</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TC</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha<sup>&#45;1</sup>) had significantly high levels of carbon stocks compared to ranches (209.78</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TC</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha<sup><span style="font-size:10px;white-space:normal;">-</span>1</sup>) and conservancies (220.73</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">TC</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">ha<sup><span style="font-size:10px;white-space:normal;">-</span>1</sup>, <i>P</i> = 0.000). Further, closed forest significantly contributed to the overall biomass and carbon stock (58%). The carbon sequestration potential was about 19.9MTCO<sub>2eq</sub> with most conservative worth of KES 39.9B (US$40M) per annum. The high carbon stock in the landscape shows the potential of dryland ecosystems as carbon sink for climate change mitigation. However, for communities to benefit from bio-carbon funds in future, sustainable landscape management and restorative measures should be practiced to enhance carbon storage and provision of other ecosystem services.</span></span></span> 展开更多
关键词 Carbon Sequestration Carbon Stock economic value Dryland Forest-Landscape Kenya
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Economic value and exploiting approaches of sea asparagus, a seawater-irrigated vegetable 被引量:1
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作者 Litian Feng Bin Ji Bin Su 《Agricultural Sciences》 2013年第9期40-44,共5页
Sea asparagus is a newly emerging seawater-irrigated vegetable. Firstly, the economic value of sea asparagus was introduced, and then, someexploiting approaches of sea asparagus werefully reviewed. The exploiting appr... Sea asparagus is a newly emerging seawater-irrigated vegetable. Firstly, the economic value of sea asparagus was introduced, and then, someexploiting approaches of sea asparagus werefully reviewed. The exploiting approaches mainly include fresh vegetable, pickle, bio-salt, health-care products, animal feed, vegetable oil, bio-diesel and skin-care products. 展开更多
关键词 Sea ASPARAGUS Seawater-Irrigated VEGETABLE economic value Exploiting APPROACHES Bio-Salt
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Response of ecosystem service value to land use/cover change in the northern slope economic belt of the Tianshan Mountains, Xinjiang, China 被引量:4
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作者 SUN Chen MA Yonggang GONG Lu 《Journal of Arid Land》 SCIE CSCD 2021年第10期1026-1040,共15页
Land use/cover change(LUCC)is becoming more and more frequent and extensive as a result of human activities,and is expected to have a major impact on human welfare by altering ecosystem service value(ESV).In this stud... Land use/cover change(LUCC)is becoming more and more frequent and extensive as a result of human activities,and is expected to have a major impact on human welfare by altering ecosystem service value(ESV).In this study,we utilized remote sensing images and statistical data to explore the spatial-temporal changes of land use/cover types and ESV in the northern slope economic belt of the Tianshan Mountains in Xinjiang Uygur Autonomous Region,China from 1975 to 2018.During the study period,LUCC in the study region varied significantly.Except grassland and unused land,all the other land use/cover types(cultivated land,forestland,waterbody,and construction land)increased in areas.From 1975 to 2018,the spatial-temporal variations in ESV were also pronounced.The total ESV decreased by 4.00×10^(8) CNY,which was primarily due to the reductions in the areas of grassland and unused land.Waterbody had a much higher ESV than the other land use/cover types.Ultimately,understanding the impact of LUCC on ESV and the interactions among ESV of different land use/cover types will help improve existing land use policies and provide scientific basis for developing new conservation strategies for ecologically fragile areas. 展开更多
关键词 land use/cover types ecosystem services human activities economic development URBANIZATION the northern slope economic belt of the Tianshan Mountains
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Carbon stock and sink economic values of forest ecosystem in the forest industry region of Heilongjiang Province, China 被引量:2
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作者 Mingjuan Li 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期875-882,共8页
The values of forest carbon stock (CSV) and carbon sink (COV) are important topics in the global carbon cycle. We quantitatively analyzed the factors affecting changes in both for forest ecosystem in 2000−2015. With m... The values of forest carbon stock (CSV) and carbon sink (COV) are important topics in the global carbon cycle. We quantitatively analyzed the factors affecting changes in both for forest ecosystem in 2000−2015. With multiple linear stepwise regression analysis, we obtained the factors that had a significant impact on changes of CSV and COV, and then the impacts of these variables on CSV and COV were used for further quantitative analysis using the vector autoregressive model. Our results indicated that both stand age and afforestation area positively affect CSV and COV;however, the forest enterprise gross output value negatively affects CSV. Stand age has the largest long-term cumulative impact on CSV and COV, reaching 40.4% and 9.8%, respectively. The impact of enterprise gross output value and afforestation area on CSV and COV is the smallest, reaching 4.0% and 0.3%, respectively. 展开更多
关键词 Carbon stock value Carbon sink value Multiple regression analysis VAR model
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Diagnostic and economic value of carcinoembryonic antigen,carbohydrate antigen 19-9,and carbohydrate antigen 72-4 in gastrointestinal cancers 被引量:4
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作者 Hai-Ning Liu Can Yao +7 位作者 Xiao-Fan Wang Ning-Ping Zhang Yan-Jie Chen Dong Pan Guo-Ping Zhao Xi-Zhong Shen Hao Wu Tao-Tao Liu 《World Journal of Gastroenterology》 SCIE CAS 2023年第4期706-730,共25页
BACKGROUND The diagnostic and economic value of carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9)and CA72-4 for gastrointestinal malignant tumors lacked evaluation in a larger scale.AIM To reassess the d... BACKGROUND The diagnostic and economic value of carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9)and CA72-4 for gastrointestinal malignant tumors lacked evaluation in a larger scale.AIM To reassess the diagnostic and economic value of the three tumor biomarkers.METHODS A retrospective analysis of all 32857 subjects who underwent CEA,CA19-9,CA72-4,gastroscopy and colonoscopy from October 2006 to May 2018 was conducted.Then,we assessed the discrimination and clinical usefulness.Total cost,cost per capita and cost-effectiveness ratios were used to evaluate the economic value of two schemes(gastrointestinal endoscopy for all people without blood tests vs both gastroscopy and colonoscopy when blood tests were positive).RESULTS The analysis of 32857 subjects showed that CEA was a qualified biomarker for colorectal cancer(CRC),while the diagnostic efficiencies of CA72-4 were catastrophic for all gastrointestinal cancers(GICs).Regarding early diagnosis,only CEA could be used for early CRC.The combination of biomarkers didn’t greatly increase the area under the curve.The economic indicators of CEA were superior to those of CA19-9,CA72-4 and any combination.At the threshold of 1.8μg/L to 10.4μg/L,all four indicators of CEA were lower than those in the scheme that conducted gastrointestinal endoscopy only.Subgroup analysis implied that the health checkup of CEA for people above 65 years old was economically valuable.CONCLUSION CEA had qualified diagnostic value for CRC and superior economic value for GICs,especially for elderly health checkup subjects.CA72-4 was not suitable as a diagnostic biomarker. 展开更多
关键词 Diagnostic test economic analysis Cost-effectiveness analysis Decision curve analysis
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Socioeconomic study and economic value of living fossil,Lingula sp.in mangrove ecosystem in Trat Province,Thailand 被引量:1
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作者 Cheewarat Printrakoon Apiwan Kamlung-ek 《Chinese Journal of Population,Resources and Environment》 2013年第3期187-199,共13页
This paper is the first recorded economic value of living fossil,an evaluation of the basic economic value of Lingula,based on the direct utilization of households for food and sale.Twenty-one local fishermen who coll... This paper is the first recorded economic value of living fossil,an evaluation of the basic economic value of Lingula,based on the direct utilization of households for food and sale.Twenty-one local fishermen who collected Lingula in Trat Province were focused on by using interview questionnaires.The animal habitats are influenced by the encroachers'age,gender and harvest method.The total economic value in 2011 was around two million baht.Those who possess fishing gear and have more money can have greater access to the product The local communities in Nong Khunsong sub-district are successful in collecting the Lingula and in doing local business.The market channel analysis is conducted at local,provincial and national levels and short market chains are demonstrated in the form of a wholesale market in the Lingula trade.This represents significant consumption by the local communities.The study further recommends sustainable conservation and management efforts at a local scale. 展开更多
关键词 LIVING FOSSIL UTILIZATION MANGROVE FOREST value evaluation sustainable management
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Potential Economic Value of Chitin and Its Derivatives as Major Biomaterials of Seafood Waste,with Particular Reference to Southeast Asia
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作者 Hsiao Wei Tan Zhi Yin Joan Lim +1 位作者 Nur Airina Muhamad Fong Fong Liew 《Journal of Renewable Materials》 SCIE EI 2022年第4期909-938,共30页
With a growing population,changes in consumerism behavior and trends in consumption in Indo-Pacific Asia,our seafood processing and consumption practices produce a large volume of waste products.There are several adva... With a growing population,changes in consumerism behavior and trends in consumption in Indo-Pacific Asia,our seafood processing and consumption practices produce a large volume of waste products.There are several advantages in regulating and sustaining shellfish processing industries.The major advantage of waste management is that it leads to better conservation of natural resources in the long run.Shrimp shell waste contains useful biomaterials,which are still untapped due to inadequate waste disposal and solid waste management.Chitin,the major component of shell waste,can be extracted either chemically or biologically.The chemical extraction approaches,which use acids and alkali,could be an environmental burden.On the other hand,biological methods can be eco-friendly alternatives for shell waste management.In this review,recent trends in management of shellfish waste as sources of chitin,conversion of chitin into chitosan,economic aspects of waste treatment and application of chitosan will be discussed. 展开更多
关键词 Seafood waste waste management CHITIN CHITOSAN economic value Southeast Asian fisheries
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The Economic Value and Valuation of Architectural Heritage 被引量:1
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作者 Svetlana Albu 《Journal of Building Construction and Planning Research》 2021年第1期1-11,共11页
This study reflects the authors’ vision on the value of architectural heritage. The theories of value are examined, and the most explicit theory is identified from a practical point of view. From our perspective, the... This study reflects the authors’ vision on the value of architectural heritage. The theories of value are examined, and the most explicit theory is identified from a practical point of view. From our perspective, the theory of entropic value is the most explicit theory from the point of view of detailing the reasoning process on the source of value, the value, and the measure of the value. The method of goods real value estimation is explained based on the analysis of the value creation mechanism, according to the entropic value theory. The analysis of the particularities of the architectural heritage from modern theory valuation perspective allowed authors to formulate methodological proposals for value estimation of real estate with cultural, architectural and historical value. 展开更多
关键词 Entropic value APPROACHES METHODS FACTORS
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Japanese Media Strategy: The Recognition of Economic Value Chains
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作者 Seiko Yasumoto 《Journalism and Mass Communication》 2012年第10期998-1011,共14页
This paper examines, as a case study, Japanese media production, remaking, and transferences of media content derived from the manga Janguru Taitei (Jungle Emperor) and contemporary Japanese government strategies to... This paper examines, as a case study, Japanese media production, remaking, and transferences of media content derived from the manga Janguru Taitei (Jungle Emperor) and contemporary Japanese government strategies to protect and promote Japanese cultural and economic value within the content business. The study utilizes methodological triangulation inclusive of textual, document, and value chain analysis. The Japanese government has progressively appreciated the intrinsic value of the media content from both a commercial and cultural context and the loss of value in unregulated segments of the regional market. In 2003, they established an Intellectual Property Strategy Group to support and promote the Japanese media content business. There has been a continuum of policy development since then to protect and amplify the financial value of Japanese media products. All of the developments in media industry are fuelled not only by government regulations, the imagination of talented artists and writers, and the growing regionalization and internationalization of the industry but also the "bottom line" emerging from the value chain. The recognition of the need for sustaining profit growth to continue the viability of original and remade content in Japan is paramount for Japan. 展开更多
关键词 Japanese media strategy economic value chains ADAPTATION
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