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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat 被引量:1
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作者 Zhikai Cheng Xiaobo Gu +5 位作者 Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1523-1540,共18页
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m... In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching. 展开更多
关键词 mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle
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The study of coal mine equipment’s comprehensive evaluation index system and evaluation method 被引量:2
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作者 王新华 史国庆 《Journal of Coal Science & Engineering(China)》 2004年第2期117-121,共5页
Equipment management is one of the important parts of business administra- tion of coal. Most of coal mines take no account of their equipment management, and have no comprehensive and effective evaluation index syste... Equipment management is one of the important parts of business administra- tion of coal. Most of coal mines take no account of their equipment management, and have no comprehensive and effective evaluation index system. Based on the analysis of the equipment evaluation measures of reform and the applications, the paper built up a comprehensive and effective evaluation index system of coal mine equipment, and im- proved the evaluation method with the use of fuzzy theory, analytic hierarchy process and entropy method. 展开更多
关键词 equipment of coal mine comprehensive evaluation index system fuzzy theory entropy method
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Index system and methods for comprehensive assessment of cross-border power grid interconnection projects 被引量:1
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作者 Teng Zhao Yizhe Jiang +4 位作者 Han Jiang Yi Gao Wei Wu Chen Wang Jinxiang Zhu 《Global Energy Interconnection》 CAS 2020年第6期532-544,共13页
With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a c... With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a critical n eed to adopt scie ntific approaches in assessi ng cross-border power grid interconnection projects.First,con sidering the promotion of large-scale renewable energy resources and improvements in system adequacy,a comprehensive assessment index system,including costs,socio-economic benefits,environmental benefits,and technical benefits,is established in this study.Second,a synthetic assessment framework is proposed for cross-border power grid interconnection projects based on the index system comprising cost-benefit analysis,with market and network simulations,iterative methods for indicator weight evaluation,and technique for order preferenee by similarity to an ideal solution(TOPSIS)method for the project rankings.Fin ally,by assessi ng and comparing three cross-border projects betwee n Europe and Asia,the proposed index system and assessment framework have been proved to be effective and feasible;the results of this system can thus support investment decision-making related to such projects in the future. 展开更多
关键词 Cross-border power grid interconnection comprehensive assessment index system Cost-benefit analysis Iterative method TOPSIS method
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Evaluation of Natural Ecological Environment in Guangzhou City Based on Remote Sensing Technology and Comprehensive Index Method 被引量:4
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作者 MA Jiaojiao NIU Anyi CHEN Zhiyun 《Journal of Landscape Research》 2016年第3期79-82,共4页
Based on the ETM remote sensing images of Guangzhou City in 2014, the spatial distribution results o f three environmental factors including vegetation coverage(NDVI), soil index(vegetation index of bare soil) and sl ... Based on the ETM remote sensing images of Guangzhou City in 2014, the spatial distribution results o f three environmental factors including vegetation coverage(NDVI), soil index(vegetation index of bare soil) and sl ope were obtained. By using comprehensive index method, the normalized environmental factors were weighted and superimposed, and the fi nal evaluation results of ecological environment in Guangzhou City were obtained. The results showed that overall situation of natural ecological environment in Guangzhou was not optimistic, that is, the area of land with bad, moderate, good and superior environment accounted for 59.70%, 35.79%, 4.50% and around 0.01% of total area of land in Guangzhou City respectively. Ecological environment was generally poor in the central urban districts in the south of Guangzhou City, while it was relatively better in the north and northeast. Attaching importance to the constr uction of greenbelts and greenways is an effective way to improve regional environmental quality and natural ecological e nvironment level. 展开更多
关键词 Remote sensing interpretation Natural ecological environment comprehensive index method Environmental assessment GUANGZHOU
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Optimization Analysis on Comprehensive Evaluation Index of Wetland Parks
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作者 Yanyan ZHANG Fanlong KONG +1 位作者 Min XI Yue LI 《Agricultural Science & Technology》 CAS 2016年第3期721-723,736,共4页
Wetland park is an important mode of wetland protection, meanwhile, construction of comprehensive index system has become the hotspot and keystone of the researches on Wetland Parks. Basing on different development st... Wetland park is an important mode of wetland protection, meanwhile, construction of comprehensive index system has become the hotspot and keystone of the researches on Wetland Parks. Basing on different development stages, this paper firstly divided the Wetland Parks into three categories, including the start-up stage, the development stage and the refinement stage. And then screened and identified the direction and keypoints of comprehensive evaluation for wetland parks in different development stages using expert scoring, questionnaire and analytic hierarchy process(AHP). 展开更多
关键词 Wetland Parks comprehensive evaluation index Optimization analysis
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Optimized Operation of Park Integrated Energy System with Source-Load Flexible Response Based on Comprehensive Evaluation Index
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作者 Xinglong Chen Ximin Cao +1 位作者 Qifan Huang He Huang 《Energy Engineering》 EI 2024年第11期3437-3460,共24页
To better reduce the carbon emissions of a park-integrated energy system(PIES),optimize the comprehensive operating cost,and smooth the load curve,a source-load flexible response model based on the comprehensive evalu... To better reduce the carbon emissions of a park-integrated energy system(PIES),optimize the comprehensive operating cost,and smooth the load curve,a source-load flexible response model based on the comprehensive evaluation index is proposed.Firstly,a source-load flexible response model is proposed under the stepped carbon trading mechanism;the organic Rankine cycle is introduced into the source-side to construct a flexible response model with traditional combined heat and power(CHP)unit and electric boiler to realize the flexible response of CHP to load;and the load-side categorizes loads into transferable,interruptible,and substitutable loads according to the load characteristics and establishes a comprehensive demand response model.Secondly,the analytic network process(ANP)considers the linkages between indicators and allows decision-makers to consider the interactions of elements in a complex dynamic system,resulting in more realistic indicator assignment values.Considering the economy,energy efficiency,and environment,the PIES optimization operation model based on the ANP comprehensive evaluation index is constructed to optimize the system operation comprehensively.Finally,the CPLEX solver inMATLABwas employed to solve the problem.The results of the example showthat the source-load flexible response model proposed in this paper reduces the operating cost of the system by 29.90%,improves the comprehensive utilization rate by 15.00%,and reduces the carbon emission by 26.98%,which effectively enhances the system’s economy and low carbon,and the comprehensive evaluation index based on the ANP reaches 0.95,which takes into account the economy,energy efficiency,and the environment,and is more superior than the single evaluation index. 展开更多
关键词 Source-load flexible response comprehensive evaluation index stepped carbon trading optimal scheduling park integrated energy system
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Configuration optimization model of multi-energy distributed generation system 被引量:2
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作者 徐青山 徐敏姣 +1 位作者 李国栋 蒋菱 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期182-188,共7页
To integrate different renewable energy resources effectively in a microgrid, a configuration optimization model of a multi-energy distributed generation(DG) system and its auxiliary equipment is proposed. The model... To integrate different renewable energy resources effectively in a microgrid, a configuration optimization model of a multi-energy distributed generation(DG) system and its auxiliary equipment is proposed. The model mainly consists of two parts, the determination of initial configuration schemes according to user preference and the selection of the optimal scheme. The comprehensive evaluation index(CEI), which is acquired through the analytic hierarchy process(AHP) weight calculation method, is adopted as the evaluation criterion to rank the initial schemes. The optimal scheme is obtained according to the ranking results. The proposed model takes the diversity of different equipment parameters and investment cost into consideration and can give relatively suitable and economical suggestions for system configuration.Additionally, unlike Homer Pro, the proposed model considers the complementation of different renewable energy resources, and thus the rationality of the multi-energy DG system is improved compared with the single evaluation criterion method which only considers the total cost. 展开更多
关键词 multi-energy complementation distributed generation(DG) optimal configuration energy management comprehensive evaluation index(CEI) analytic hierarchy process(AHP)
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I-DCGAN and TOPSIS-IFP:A simulation generation model for radiographic flaw detection images in light alloy castings and an algorithm for quality evaluation of generated images
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作者 Ming-jun Hou Hao Dong +7 位作者 Xiao-yuan Ji Wen-bing Zou Xiang-sheng Xia Meng Li Ya-jun Yin Bao-hui Li Qiang Chen Jian-xin Zhou 《China Foundry》 SCIE EI CAS CSCD 2024年第3期239-247,共9页
The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy castings.H... The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy castings.However,the efficacy of deep learning models hinges upon a substantial abundance of flaw samples.The existing research on X-ray image augmentation for flaw detection suffers from shortcomings such as poor diversity of flaw samples and low reliability of quality evaluation.To this end,a novel approach was put forward,which involves the creation of the Interpolation-Deep Convolutional Generative Adversarial Network(I-DCGAN)for flaw detection image generation and a comprehensive evaluation algorithm named TOPSIS-IFP.I-DCGAN enables the generation of high-resolution,diverse simulated images with multiple appearances,achieving an improvement in sample diversity and quality while maintaining a relatively lower computational complexity.TOPSIS-IFP facilitates multi-dimensional quality evaluation,including aspects such as diversity,authenticity,image distribution difference,and image distortion degree.The results indicate that the X-ray radiographic images of magnesium and aluminum alloy castings achieve optimal performance when trained up to the 800th and 600th epochs,respectively.The TOPSIS-IFP value reaches 78.7%and 73.8%similarity to the ideal solution,respectively.Compared to single index evaluation,the TOPSIS-IFP algorithm achieves higher-quality simulated images at the optimal training epoch.This approach successfully mitigates the issue of unreliable quality associated with single index evaluation.The image generation and comprehensive quality evaluation method developed in this paper provides a novel approach for image augmentation in flaw recognition,holding significant importance for enhancing the robustness of subsequent flaw recognition networks. 展开更多
关键词 light alloy casting flaw detection image generator DISCRIMINATOR comprehensive evaluation index
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Investigation of Dominant Populations of Late-summer Phytoplankton and Comprehensive Nutritional Evaluation of Water Quality in Bailang Lake
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作者 张静 杨坤 +2 位作者 程云生 李静 卢文轩 《Agricultural Science & Technology》 CAS 2013年第3期453-457,共5页
[Objective] This study aimed to investigate the dominant populations of late-summer phytoplankton and conduct comprehensive nutritional evaluation of water quality in Bailang Lake. [Method] A series of water quality s... [Objective] This study aimed to investigate the dominant populations of late-summer phytoplankton and conduct comprehensive nutritional evaluation of water quality in Bailang Lake. [Method] A series of water quality survey and phytoplankton sampling was conducted in Bailang Lake in September 2011, a total of four sam- pling points were set, to detect and analyze the total nitrogen, total phosphorus, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen and permanganate index in water samples and further conduct comprehensive nutritional evaluation of the water quality factors using comprehensive nutritional state index method. [Result] Water in Bailang Lake was neutral to slightly alkaline with pH of 8.57. The average water trans- parency was 0.4 m, with relatively high content of dissolved oxygen. The content of total nitrogen was relatively high of 3.043 mg/L averagely. Comprehensive nutritional evaluation showed that the water quality of Bailang Lake belonged to moderate eu- trophication. As can be seen from various comprehensive nutritional state indices TLI, the contribution of transparency, chlorophyll a and total nitrogen to the eutrophi- cation in Bailang Lake was the greatest, followed by the permanganate index and total phosphorus. Statistical analysis showed that the average weight-biomass of phy- toplankton in Bailang Lake was 6.442 mg/L, and the average was 146.46x104 individuals/ml. There were eight dominant species in Bailang Lake, including Scenedesmus, Tetraedron, Merismopedia sinica, Phormidium, Merismopedia, Tribonema, Chroomonas and Synedra. [Conclusion] This study provided data informa- tion for the environmental protection and fisheries production in Bailang Lake. 展开更多
关键词 Bailang Lake comprehensive nutritional evaluation index PHYTOPLANKTON Dominant species
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A novel use of the comprehensive complication index in perihilar cholangiocarcinoma surgery
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作者 Edoardo Poletto Simone Conci +3 位作者 Tommaso Campagnaro Mario De Bellis Laura Alaimo Andrea Ruzzenente 《Hepatobiliary Surgery and Nutrition》 SCIE 2024年第1期139-142,共4页
It is well known that radical intent surgery is,as of today,the only curative treatment available for perihilar cholangiocarcinoma(pCCA);the standard surgical procedure includes major hepatectomy with caudate lobe res... It is well known that radical intent surgery is,as of today,the only curative treatment available for perihilar cholangiocarcinoma(pCCA);the standard surgical procedure includes major hepatectomy with caudate lobe resection and extrahepatic bile duct resection(1).A recent paper set the benchmark values for pCCA surgery:in this paper,acceptable benchmark values for morbidity. 展开更多
关键词 comprehensive complication index(CCI) perihilar cholangiocarcinoma(pCCA) postoperative complication TRAJECTORY
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Coupling coordination analysis of Mazu culture,socio-economy and ecological environment of Meizhou Island
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作者 FU Wei-jia WU Ying-qi +2 位作者 LUO Zi-xuan YAO Jun-bing FU Li-jun 《Ecological Economy》 2024年第1期85-100,共16页
Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound s... Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound system was constructed.The index weights were determined by AHP-entropy method,and the coupling degree,coordinated degree,comprehensive evaluation index and grey correlation degree of MSE system of Mazu Island from 2012 to 2022 were measure.The results showed that:(1)the comprehensive evaluation indexes of the three subsystems was on the rise in general,but the evaluation index of the ecological subsystems increased relatively slowly.(2)The coupling degree was only in the running-in stage in 2012,and the other years were in the coordinated coupling stage.(3)The coupling coordination degree increased from 0.35 in 2012 to 0.82 in 2022,the coupling coordination level was changed from mild imbalance to good coordination.(4)Through the comparison of grey correlation degree,the 24 indexes in the evaluation index system had great influence on the coupling coordination degree of MSE system.The coupling coordination degree was closely related to the development of socio-economy and the spread of Mazu culture.With the rapid development of tourism brought about by the spread of Mazu culture,the pressure on the ecological environment will be increasing.Compared with the rapid growth of tourism and economy,it is equally important to strengthen environmental protection and pay attention to the quality of ecological environment development. 展开更多
关键词 Meizhou Island Mazu culture socio-economy ecological environment comprehensive evaluation index coupling coordination degree
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Comprehensive drought monitoring in Yunnan Province, China using multisource remote sensing data 被引量:1
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作者 WANG Jin-liang YU Yuan-he 《Journal of Mountain Science》 SCIE CSCD 2021年第6期1537-1549,共13页
Development of drought monitoring techniques is important for understanding and mitigating droughts and for rational agricultural management. This study used data from multiple sources, including MOD13 A3, TRMM 3 B43,... Development of drought monitoring techniques is important for understanding and mitigating droughts and for rational agricultural management. This study used data from multiple sources, including MOD13 A3, TRMM 3 B43, and SRTMDEM, for Yunnan Province, China from 2009 to 2018 to calculate the tropical rainfall condition index(TRCI), vegetation condition index(VCI), temperature condition index(TCI), and elevation factors. Principal component analysis(PCA) and analytic hierarchy process(AHP) were used to construct comprehensive drought monitoring models for Yunnan Province. The reliability of the models was verified, following which the drought situation in Yunnan Province for the past ten years was analysed. The results showed that:(1) The comprehensive drought index(CDI) had a high correlation with the standardized precipitation index, standardized precipitation evapotranspiration index, temperature vegetation dryness index, and CLDAS(China Meteorological Administration land data assimilation system), indicating that the CDI was a strong indicator of drought through meteorological, remote sensing and soil moisture monitoring.(2) The droughts from 2009 to 2018 showed generally consistent spatiotemporal changes. Droughts occurred in most parts of the province, with an average drought frequency of 29% and four droughtprone centres.(3) Monthly drought coverage during 2009 to 2014 exceeded that over 2015 to 2018. January had the largest average drought coverage over the study period(61.92%). Droughts at most stations during the remaining months except for October exhibited a weakening trend(slope > 0). The CDI provides a novel approach for drought monitoring in areas with complex terrain such as Yunnan Province. 展开更多
关键词 Multisource data comprehensive drought index(CDI) Standardized precipitation index(SPI) Standardized precipitation evapotranspiration index(SPEI) Temperature vegetation dryness index(TVDI) Yunnan Province China
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Applicable conditions for a classification system of aquifer-protective mining in hallow coal seams 被引量:4
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作者 Liu Yude Zhang Dongsheng +1 位作者 Fan Gangwei Yah Shoufeng 《Mining Science and Technology》 EI CAS 2011年第3期381-387,共7页
Based on the conclusions of domestic and foreign research, we have analyzed the collapse-fall characteristics of overlying strata and the mechanism of aquifer-protective mining in shallow coal seam working faces at th... Based on the conclusions of domestic and foreign research, we have analyzed the collapse-fall characteristics of overlying strata and the mechanism of aquifer-protective mining in shallow coal seam working faces at the Shendong Mine. We have selected the height of the water-conducting fracture zone in overlying strata as a composite index and established the applicable conditions of aquifer-protective mining in shallow coal seams with a multi-factor synthetic-index classification method. From our calculations and analyses of variance, we used factors such as the overlying strata strength, mining disturbing factors and rock integrity as related factors of the composite index. We have classified the applicable conditions of aquifer-protective mining in shallow coal seams into seven types by comparing the result of the height of water-conducting fractured zones of long-wall and short-wall working faces with the thickness of the bedrock, the thickness of the weathered zone and the size of safety coal-rock pillars. As a result, we propose the preliminary classification system of aquifer-protective mining in shallow coal seams. It can provide a theoretical guidance for safe applications of aquifer-protective mining technology in shallow coal seams under similar conditions. 展开更多
关键词 Depth limits of shallow coal seamsAquifer-protective mining comprehensive classification index analysisWater-conducting cranny zone Analysis of variance
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A Preliminary Study on Systems Engineering-Based Method for the Evaluation of Allelopathic Potential in Crops and Its Application
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作者 ZUO Sheng-peng MA Yong-qing 《Agricultural Sciences in China》 CAS CSCD 2007年第1期68-77,共10页
The objective of this study was to develop a method to assess and analyze the total allelopathic potential of crop germplasm and to test this method on four winter wheat accessions commonly planted in the Loess Platea... The objective of this study was to develop a method to assess and analyze the total allelopathic potential of crop germplasm and to test this method on four winter wheat accessions commonly planted in the Loess Plateau. A systems engineering model was developed and used to evaluate the total allelopathic potential of crop cultivars. In addition, a method for quantifying the total allelopathic potential in crop accessions was presented. Total allelopathic potential of four winter wheat accessions from the Loess Plateau was estimated and compared using a systems theory approach. The model assessed allelopathic potential in different parts of the plants from the time wheat turned green in spring until maturity. Results from these models indicated that the four wheat accessions had very weak allelopathic potential. Allelopathic potential declined in the order Xiaoyan 22 〉 Ningdong 1 〉 Fengchan 3 〉 Bima 1. This system engineering evaluation method allows for the assessment of allelopathic potential among crop varieties. It will help plant breeders to select and develop allelopathic crop accessions that combine weed suppression properties with agronomic traits related to yield and quality. 展开更多
关键词 systems engineering principles evaluation of crop allelopathic potential synergetic indices of allelopathic potential comprehensive index of allelopathic potential genetic breeding of allelopathic crop accessions
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Health Assessment and Protection Countermeasures of Ecosystem of the Dajiu Lake in Shennongjia
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作者 Decai HE Xiaobin PAN +1 位作者 Ying CUI Yanyan WANG 《Meteorological and Environmental Research》 CAS 2021年第3期19-22,共4页
The Dajiu Lake is an important subtropical alpine wetland in central China.In May of 2019,an ecological investigation was conducted on water quality and aquatic organisms(phytoplankton,zooplankton and zoobenthos)of th... The Dajiu Lake is an important subtropical alpine wetland in central China.In May of 2019,an ecological investigation was conducted on water quality and aquatic organisms(phytoplankton,zooplankton and zoobenthos)of the Dajiu Lake in Shennongjia forest region.The results showed that parameters of water quality in No.5 and No.9 sub lakes of the Dajiu Lake corresponded with standard of class II water of the Environmental Quality Standards for Surface Water(GB 3838-2002),while other sub lakes corresponded with standard of class III water.Diversity indexes of phytoplankton and zooplankton ranged from 2.0 to 3.0,and there were two families(Chironomidae and Libellulidae Rambur)of one phylum(Arthropoda)in zoobenthos.Comprehensive health index of entropy weight was used to evaluate water ecological status of the Dajiu Lake,and water quality of No.5,No.8 and No.9 sub lakes was in a healthy status,while other sub lakes were in sub-health status.Finally,corresponding countermeasures were proposed according to protection needs of the Dajiu Lake. 展开更多
关键词 The Dajiu Lake Health of ecosystem comprehensive health index of entropy weight Evaluation Protection countermeasures
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Spatial changes and driving factors of lake water quality in Inner Mongolia, China
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作者 REN Xiaohui YU Ruihong +10 位作者 LIU Xinyu SUN Heyang GENG Yue QI Zhen ZHANG Zhuangzhuang LI Xiangwei WANG Jun ZHU Penghang GUO Zhiwei WANG Lixin XU Jifei 《Journal of Arid Land》 SCIE CSCD 2023年第2期164-179,共16页
Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain uncl... Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain unclear.This study aimed to identify the spatial changes in water quality and the driving factors of seven lakes(Juyanhai Lake,Ulansuhai Lake,Hongjiannao Lake,Daihai Lake,Chagannaoer Lake,Hulun Lake,and Wulannuoer Lake)across the longitudinal axis(from the west to the east)of Inner Mongolia.Large-scale research was conducted using the comprehensive trophic level index(TLI(Σ)),multivariate statistics,and spatial analysis methods.The results showed that most lakes in Inner Mongolia were weakly alkaline.Total dissolved solids and salinity of lake water showed obvious zonation characteristics.Nitrogen and phosphorus were identified as the main pollutants in lakes,with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L,respectively.The values of TLI(Σ)ranged from 49.14 to 71.77,indicating varying degrees of lake eutrophication,and phosphorus was the main driver of lake eutrophication.The lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI(Σ).The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake,whereas the opposite trend was observed for lake trophic level.The intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water quality.It is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological environment.These findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia,which can be used to develop strategies for lake ecosystem protection and water resources management in this region. 展开更多
关键词 SALINITY lake eutrophication lake water quality comprehensive trophic level index anthropogenic activities Daihai Lake Inner Mongolia
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Vulnerability assessment of marine economic system based on comprehensive index and catastrophe progression model
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作者 Sheng Gao Huihui Sun +3 位作者 Miaosen Ma Yanyan Lu Yuan Yao Wei Liu 《Ecosystem Health and Sustainability》 SCIE 2020年第1期696-707,695,共13页
The sustainable development of the marine economic system to accurately grasp the dynamic evolution characteristics and main driving factors of the vulnerability of the marine economic system so as to effectively iden... The sustainable development of the marine economic system to accurately grasp the dynamic evolution characteristics and main driving factors of the vulnerability of the marine economic system so as to effectively identify the problems in the operation of the marine economy is extremely important.Based on the establishment of a three-level assessment index system for the vulnerability of the marine economic system,the vulnerability of the marine economic system of Jiangsu Province in 2008-2016 was evaluated by using the comprehensive index model and the catastrophe progression model,and the results were compared based on the unified evaluation criteria.The main influencing factors were analyzed by principal component analysis and Pearson correlation analysis.It’s found that 2014,2015,and 2012 are in a general state,2009 and 2010 are in a poor state,and the vulnerability state from 2008 to 2011 is lower than that in 2012.The overall volatility is small indicating a stable system.Among them,the scale of marine industry and profit and loss of marine resources are the main components of marine economic system vulnerability having the highest correlation with the vulnerability of marine economic system.This study enriches the theoretical method and empirical research on the vulnerability of the marine economic system and has practical significance in allowing for timely targeted control measures to affect the vulnerability of the marine economic system. 展开更多
关键词 Marine economic system VULNERABILITY comprehensive index Catastrophe series
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Assessment of river ecosystem health in Tianjin City,China:index of ecological integrity and water comprehensive pollution approach
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作者 Yan WANG Shang ZHAO +5 位作者 Mingdong SUN Xubo LV Wenqian CAI Xiangqin XU Hongxiang GE Kun LEI 《Frontiers of Earth Science》 SCIE CSCD 2021年第4期936-946,共11页
Evaluation of the river ecological environment can provide a basis for river management and ecological restoration.To conduct a comprehensive health assessment of the rivers in Tianjin,their biological,physical,and ch... Evaluation of the river ecological environment can provide a basis for river management and ecological restoration.To conduct a comprehensive health assessment of the rivers in Tianjin,their biological,physical,and chemical indicators are investigated on the basis of 32 river monitoring sites from August to September 2018.The comprehensive pollution and ecological integrity indexes of the rivers are analyzed.Results of the two evaluations,compared to achieve the river ecological environment evaluation,are as follows.1)Index of Ecological Integrity evaluation shows that among the sampling points,18.8%are"healthy",28.1%are"sub-healthy",40.6%are"fair",6.3%are"poor",and 6.3%are"very poor".2)The comprehensive evaluation of the chemical properties of the 32 river ecosystems in Tianjin shows severe overall river pollution and low standard water function area.Of the total sampling sites,16(50%)are heavily contaminated and 10(31.3%)are moderately contaminated.Excessive chemical oxygen demand and ammonia nitrogen are the main causes of water pollution.3)The Index of Ecological Integrity(IEI)has high correspondence with environmental factors.Pearson correlation analysis results show that the IEI index is significantly correlated with permanganate index(R=-0.453;P=0.023<0.05).Analysis results using BEST show that ammonia nitrogen is the best environmental parameter to explain the changes in IEI(R_(ho)=0.154;P=0.02<0.05)and those using RELATE show significant correlation between the biotic index and the environmental parameter matrices(R_(ho)=0.154;P=0.034<0.05). 展开更多
关键词 water ecological function zone index of water comprehensive pollution index of ecological integrity TIANJIN
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Study on Urban Construction Land Suitability Evaluation in Southwestern Mountainous Areas of Yunnan Province Based on the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" : A Case in Lianghe County 被引量:4
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作者 贺一梅 杨子生 +2 位作者 张博胜 邓有旺 张德省 《Agricultural Science & Technology》 CAS 2014年第10期1774-1777,1780,共5页
According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat ... According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China. 展开更多
关键词 Mountainous area Constructive land Suitability evaluation comprehensive suitability index Southwestern Yunnan Province
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Comparative Advantage of Maize Production in Jilin Province 被引量:2
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作者 张大瑜 吴景贵 +4 位作者 陈日曌 祝延立 吕铁彪 赵仁贵 刘武仁 《Agricultural Science & Technology》 CAS 2010年第6期53-56,共4页
The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed th... The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed that compared with other provinces in China,there was obvious comparative advantage in sow area index and unit yield index of maize in Jilin,the average of which stood for the first and the fourth in China from 2002 to 2006;there was no comparative advantage of benefit index compared with the average value of the whole countries,the average of which stood for the 14th in China from 2002 to 2006;the comprehensive comparative advantage in Jilin provincial maize production showed significant comparative advantage,the average of which stood for the fourth in China from 2002 to 2006.On the basis of the above,the suggestions to develop maize production in Jilin province had been put forward. 展开更多
关键词 Sow area index Unit yield index Benefit index comprehensive comparative advantage index MAIZE Jilin Province
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