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Disentangling the effects of management and climate change on habitat suitability for saproxylic species in boreal forests
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作者 Ellinoora Ekman María Triviño +3 位作者 Clemens Blattert Adriano Mazziotta Maria Potterf Kyle Eyvindson 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期121-133,共13页
Forest degradation induced by intensive forest management and temperature increase by climate change are resulting in biodiversity decline in boreal forests.Intensive forest management and high-end climate emission sc... Forest degradation induced by intensive forest management and temperature increase by climate change are resulting in biodiversity decline in boreal forests.Intensive forest management and high-end climate emission scenarios can further reduce the amount and diversity of deadwood,the limiting factor for habitats for saproxylic species in European boreal forests.The magnitude of their combined effects and how changes in forest management can affect deadwood diversity under a range of climate change scenarios are poorly understood.We used forest growth simulations to evaluate how forest management and climate change will individually and jointly affect habitats of red-listed saproxylic species in Finland.We simulated seven forest management regimes and three climate scenarios(reference,RCP4.5 and RCP8.5)over 100 years.Management regimes included set aside,continuous cover forestry,business-as-usual(BAU)and four modifications of BAU.Habitat suitability was assessed using a speciesspecific habitat suitability index,including 21 fungal and invertebrate species groups.“Winner”and“loser”species were identified based on the modelled impacts of forest management and climate change on their habitat suitability.We found that forest management had a major impact on habitat suitability of saproxylic species compared to climate change.Habitat suitability index varied by over 250%among management regimes,while overall change in habitat suitability index caused by climate change was on average only 2%.More species groups were identified as winners than losers from impacts of climate change(52%–95%were winners,depending on the climate change scenario and management regime).The largest increase in habitat suitability index was achieved under set aside(254%)and the climate scenario RCP8.5(>2%),while continuous cover forestry was the most suitable regime to increase habitat suitability of saproxylic species(up to+11%)across all climate change scenarios.Our results show that close-to-nature management regimes(e.g.,continuous cover forestry and set aside)can increase the habitat suitability of many saproxylic boreal species more than the basic business-as-usual regime.This suggests that biodiversity loss of many saproxylic species in boreal forests can be mitigated through improved forest management practices,even as climate change progresses. 展开更多
关键词 BIODIVERSITY Simulations FINLAND Forest planning Habitat suitability DEADWOOD
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Suitable region of dynamic optimal interpolation for efficiently altimetry sea surface height mapping
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作者 Jiasheng Shi Taoyong Jin 《Geodesy and Geodynamics》 EI CSCD 2024年第2期142-149,共8页
The dynamic optimal interpolation(DOI)method is a technique based on quasi-geostrophic dynamics for merging multi-satellite altimeter along-track observations to generate gridded absolute dynamic topography(ADT).Compa... The dynamic optimal interpolation(DOI)method is a technique based on quasi-geostrophic dynamics for merging multi-satellite altimeter along-track observations to generate gridded absolute dynamic topography(ADT).Compared with the linear optimal interpolation(LOI)method,the DOI method can improve the accuracy of gridded ADT locally but with low computational efficiency.Consequently,considering both computational efficiency and accuracy,the DOI method is more suitable to be used only for regional applications.In this study,we propose to evaluate the suitable region for applying the DOI method based on the correlation between the absolute value of the Jacobian operator of the geostrophic stream function and the improvement achieved by the DOI method.After verifying the LOI and DOI methods,the suitable region was investigated in three typical areas:the Gulf Stream(25°N-50°N,55°W-80°W),the Japanese Kuroshio(25°N-45°N,135°E-155°E),and the South China Sea(5°N-25°N,100°E-125°E).We propose to use the DOI method only in regions outside the equatorial region and where the absolute value of the Jacobian operator of the geostrophic stream function is higher than1×10^(-11). 展开更多
关键词 Dynamic optimal interpolation Linearoptimal interpolation Satellite altimetry Sea surface height Suitable region
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Potentially Suitable Area and Change Trends of Tulipa iliensis under Climate Change
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作者 Douwen Qin Weiqiang Liu +1 位作者 Jiting Tian Xiuting Ju 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期981-1005,共25页
Tulipa iliensis,as a wild plant resource,possesses high ornamental value and can provide abundant parental materials for tulip breeding.The objective of this research was to forecast the worldwide geographical spread ... Tulipa iliensis,as a wild plant resource,possesses high ornamental value and can provide abundant parental materials for tulip breeding.The objective of this research was to forecast the worldwide geographical spread of Tulipa iliensis by considering bioclimatic,soil,and topographic variables,the findings of this research can act as a benchmark for the conservation,management,and utilization of Tulipa iliensis as a wild plant resource.Research results indicate that all 12 models have an area under curve(AUC)of the receiver operating characteristic curve(ROC)values greater than 0.968 for the paleoclimatic,current,and future climate scenarios,this suggests an exceptionally high level of predictive accuracy for the models.The distribution of Tulipa iliensis is influenced by several key factors.These factors include the mean temperature of the driest quarter(Bio9),calcium carbonate content(T_CACO3),slope,precipitation of the driest month(Bio14),Basic saturation(T_BS),and precipitation of the coldest quarter(Bio19).During the three paleoclimate climate scenarios,the appropriate habitats for Tulipa iliensis showed a pattern of expansion-contraction expansion.Furthermore,the total suitable area accounted for 13.38%,12.28%,and 13.28%of the mainland area,respectively.According to the current climate scenario,the High-suitability area covers 61.78472×10^(4)km^(2),which accounts for 6.57%of the total suitable area,The Midsuitability area covers 190.0938×10^(4)km^(2),accounting for 20.2%of the total suitable area,this represents a decrease of 63.53%~67.13%compared to the suitable area of Tulipa iliensis under the paleoclimate scenario.Under the Shared Socioeconomic Pathways(SSP)scenarios,in 2050 and 2090,Tulipa iliensis is projected to experience a decrease in the High,Mid,and Low-suitability areas under the SSP126 climate scenario by 7.10%~12.96%,2.96%~4.27%and 4.80%~7.96%,respectively.According to the SSP245 scenario,the high suitability area experienced a slight expansion of 2.26%in 2050,but a reduction of 6.32%in 2090.In the SSP370 scenario,the High-suitability areas had a larger reduction rate of 11.24%in 2050,while the Mid-suitability and Low-suitability areas had smaller expansion rates of 0.36%and 4.86%,respectively.In 2090,the High-suitability area decreased by 4.84%,while the Mid and Low-suitability areas experienced significant expansions of 15.73%and 45.89%,respectively.According to the SSP585 scenario,in the future,the High,Mid,and Low-suitability areas are projected to increase by 5.09%~7.21%,7.57%~17.66%,and 12.30%~48.98%,respectively.The research offers enhanced theoretical direction for preserving Tulipa iliensis’genetic variety amidst evolving climatic scenarios. 展开更多
关键词 Tulipa iliensis MaxEnt model climate change distribution of suitable habitats
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Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China
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作者 YANG Ao TU Wenqin +9 位作者 YIN Benfeng ZHANG Shujun ZHANG Xinyu ZHANG Qing HUANG Yunjie HAN Zhili YANG Ziyue ZHOU Xiaobing ZHUANG Weiwei ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2024年第10期1380-1408,共29页
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of... In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China. 展开更多
关键词 HALOPHYTES climate change global warming maximum entropy(MaxEnt)model soil salinization suitable habitats Northwest China
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Spatial and Temporal Differences of Climate Suitability of Ice and Snow Sports in Major Ski Tourism Destinations in China
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作者 XIE Xia PANG Zhengjin +2 位作者 ZHU Haiqiang GAO Jun ZHOU Qiaoya 《Chinese Geographical Science》 SCIE CSCD 2024年第5期967-982,共16页
Ice and snow tourism in China has grown significantly since the country successfully hosted the Beijing Winter Olympics.Climatic conditions profoundly impact the development of ice and snow tourism;however,most studie... Ice and snow tourism in China has grown significantly since the country successfully hosted the Beijing Winter Olympics.Climatic conditions profoundly impact the development of ice and snow tourism;however,most studies have focused on constructing different climate suitability indicators for ice and snow tourism to evaluate individual regions,lacking horizontal comparative studies across multiple regions.This study aims to enrich the connotation of climate suitability for ice and snow sports,establish an evaluation model based on snowfall amount,temperature,and wind speed,and use daily meteorological data from 1991 to 2021 to horizontally compare the climate suitability for ice and snow sports in major ski tourism destinations in China.This study boasts four major findings:1)the average ice and snow sports climate index of each region decreases over time,and the overall suitability of the climate for ice and snow sports is reducing;2)northern Xinjiang exhibits the most evident regional differentiation from‘very suitable’to‘generally suitable’;3)the spatial zoning of climate suitability for ice and snow sports exhibits heterogeneity,as northern Xinjiang is divided into two‘suitable and above’zones with rotating empirical orthogonal function(REOF).Correspondingly,the four provinces of Hebei,Heilongjiang,Jilin,and Liaoning are divided into three‘generally suitable and above’zones;4)snowfall amount is the main factor affecting the climate suitability of ice and snow sports in the major ski tourist destinations in China. 展开更多
关键词 ice and snow tourism climate suitability rotating empirical orthogonal function(REOF) spatial division China
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Evaluation of Walking Suitability of Historical and Cultural Blocks: A Case Study of Shichahai in Beijing
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作者 LI Ruoxuan SUN Shuai 《Journal of Landscape Research》 2024年第5期33-37,共5页
This paper focuses on the Shichahai area of Beijing to assess the walking suitability of its coastal and surrounding streets.Shichahai area,covering an area of about 302 hm2,is an important historical and cultural pro... This paper focuses on the Shichahai area of Beijing to assess the walking suitability of its coastal and surrounding streets.Shichahai area,covering an area of about 302 hm2,is an important historical and cultural protection zone in Beijing,with rich historical and cultural heritage and modern urban activities.This paper uses literature analysis,field research and Baidu Street View map data to construct an evaluation system of three first-level indicators,including space safety,walking comfort and landscape enrichment,and determines the weight of each indicator by expert scoring method.The street is evaluated and analyzed by means of statistical analysis.In order to improve the walking environment of Shichahai area,it is suggested to monitor and manage street hygiene,replant vegetation to improve the green coverage rate and landscape richness,and optimize the walking space design to ensure the safety and comfort of pedestrians.These measures aim to balance historical preservation with modern needs and promote the protection and development of historical and cultural districts. 展开更多
关键词 suitability evaluation Historical and cultural districts Shichahai
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Development of a Suitable,Cultural,and Life-Oriented Kindergarten Curriculum
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作者 Yuxuan Sun 《Journal of Contemporary Educational Research》 2024年第1期88-95,共8页
The technological revolution and the explosion of information have created a diverse world.More and more so-called advanced cultures are entering kindergartens,prompting us to think about how to correctly develop the ... The technological revolution and the explosion of information have created a diverse world.More and more so-called advanced cultures are entering kindergartens,prompting us to think about how to correctly develop the existing local cultures in the cultural context,while simultaneously accepting and absorbing the appropriate parts of foreign cultures.It is also necessary to maintain a balance between diversity and localization to prevent kindergartens from becoming a“colony”of foreign cultures.The development of suitable,cultural,and life-oriented kindergarten curricula from different perspectives is the focus of such a balance.Only in this way can kindergartens truly fulfill their educational functions and provide a vibrant and colorful environment for children. 展开更多
关键词 Kindergarten curriculum suitability CULTURE Life-oriented
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Suitability evaluation on marine ranching in Guangdong,South China 被引量:1
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作者 Anning SUO Weiguo ZHOU Dewen DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期778-791,共14页
The ecological suitability of marine resources and environmental conditions for marine ranching in Guangdong,South China was evaluated.Niche theory was used to establish an ecological suitability evaluation model for ... The ecological suitability of marine resources and environmental conditions for marine ranching in Guangdong,South China was evaluated.Niche theory was used to establish an ecological suitability evaluation model for marine ranching site selection,and suitability evaluation of marine ranching was conducted in.Results show that the ecological suitability index of marine ranching site selection was greater than 64.0 in 20 sites,including offshore Shantou Bay,offshore Zhanjiang Port,and Longdou Bay etc.,which are the priority areas for marine ranching.In other 13 sites,the ecological suitability index ranged between 8.0 and 32.0,including Houjiang Bay,Haimen Bay,and Jieshi Bay etc.,indicating the suitability for marine ranching.However,the ecological suitability index was 0 in Shantou Bay,Zhujiang(Pearl)River estuary,Huangmao Sea,Guanghai Bay,Zhanjiang Port,Qiongzhou Strait,and Anpu Port.These sites are thus unsuitable for marine ranching.This study provides a theoretical basis for site selection and planning of marine ranching in Guangdong Province. 展开更多
关键词 marine ranching site suitability EVALUATION ecological niche Guangdong Province
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Forest use suitability:Towards decision-making-oriented sustainable management of forest ecosystem services 被引量:1
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作者 Goran Krsnik Keith MReynolds +3 位作者 Philip Murphy Steve Paplanus Jordi Garcia-Gonzalo JoséRamón González Olabarria 《Geography and Sustainability》 CSCD 2023年第4期414-427,共14页
Management of forest lands considering multi-functional approaches is the basis to sustain or enhance the provi-sion of specific benefits,while minimizing negative impacts to the environment.Defining a desired managem... Management of forest lands considering multi-functional approaches is the basis to sustain or enhance the provi-sion of specific benefits,while minimizing negative impacts to the environment.Defining a desired management itinerary to a forest depends on a variety of factors,including the forest type,its ecological characteristics,and the social and economic needs of local communities.A strategic assessment of the forest use suitability(FUS)(namely productive,protective,conservation-oriented,social and multi-functional)at regional level,based on the provision of forest ecosystem services and trade-offs between FUS alternatives,can be used to develop management strategies that are tailored to the specific needs and conditions of the forest.The present study assesses the provision of multiple forest ecosystem services and employs a decision model to identify the FUS that sup-ports the most present and productive ecosystem services in each stand in Catalonia.For this purpose,we apply the latest version of the Ecosystem Management Decision Support(EMDS)system,a spatially oriented decision support system that provides accurate results for multi-criteria management.We evaluate 32 metrics and 12 as-sociated ecosystem services indicators to represent the spatial reality of the region.According to the results,the dominant primary use suitability is social,followed by protective and productive.Nevertheless,final assignment of uses is not straightforward and requires an exhaustive analysis of trade-offs between all alternative options,in many cases identifying flexible outcomes,and increasing the representativeness of multi-functional use.The assignment of forest use suitability aims to significantly improve the definition of the most adequate management strategy to be applied. 展开更多
关键词 Forest ecosystem services Decision making Forest use suitability Multi-objective management Geospatial analysis
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Explicit Isogeometric Topology Optimization Method with Suitably Graded Truncated Hierarchical B-Spline 被引量:1
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作者 Haoran Zhu Xinhao Gao +3 位作者 Aodi Yang Shuting Wang Xianda Xie Tifan Xiong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1435-1456,共22页
This work puts forward an explicit isogeometric topology optimization(ITO)method using moving morphable components(MMC),which takes the suitably graded truncated hierarchical B-Spline based isogeometric analysis as th... This work puts forward an explicit isogeometric topology optimization(ITO)method using moving morphable components(MMC),which takes the suitably graded truncated hierarchical B-Spline based isogeometric analysis as the solver of physical unknown(SGTHB-ITO-MMC).By applying properly basis graded constraints to the hierarchical mesh of truncated hierarchical B-splines(THB),the convergence and robustness of the SGTHB-ITOMMC are simultaneously improved and the tiny holes occurred in optimized structure are eliminated,due to the improved accuracy around the explicit structural boundaries.Moreover,an efficient computational method is developed for the topological description functions(TDF)ofMMC under the admissible hierarchicalmesh,which consists of reducing the dimensionality strategy for design space and the locally computing strategy for hierarchical mesh.We apply the above SGTHB-ITO-MMC with improved efficiency to a series of 2D and 3Dcompliance design problems.The numerical results show that the proposed SGTHB-ITO-MMC method outperforms the traditional THB-ITO-MMCmethod in terms of convergence rate and efficiency.Therefore,the proposed SGTHB-ITO-MMC is an effective way of solving topology optimization(TO)problems. 展开更多
关键词 Isogeometric topology optimization moving morphable components truncated hierarchical B-spline suitably graded hierarchical mesh
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Extensive Pineapple Production Constraints and Land Suitability in the Centre Region of Cameroon
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作者 Georges Marius Etame Kossi Honoré Beyegue Djonko +1 位作者 Alexis Boukong Francis Brice Silatsa Tedou 《Agricultural Sciences》 CAS 2023年第2期240-255,共16页
The low level of productivity observed in pineapple fields in Centre Came-roon must be sustainably reduced in order to increase producers’ income while using the same resources. The identification and control of prod... The low level of productivity observed in pineapple fields in Centre Came-roon must be sustainably reduced in order to increase producers’ income while using the same resources. The identification and control of production constraints are key steps in optimizing the use of limited resources. To this end, the FAO land assessment methodology following the Fuzzy-MCDM pro-tocol was used for the two pineapple production basins in the Centre, namely Awae and Bokito. It was found that the land in Awae Basin is moderately suitable S2sf with constraints imposed by texture, pH and base saturation. In the Bokito Basin, 25% of the land is suitable S1wf and 75% is moderately suitable S2wsf with constraints imposed by soil texture (27%), temporary soil water saturation (99%), pH, base saturation and exchangeable sodium. Constraint correction improves the land index (potential suitability) and re-mains limited by permanent constraints that cannot be corrected. Improve-ment of the technical itinerary through modification of plant densities, selec-tion of improved cultivars and balanced fertilization must be undertaken to optimize pineapple production in Centre Cameroon. 展开更多
关键词 Land suitability CONSTRAINTS PINEAPPLE Centre Cameroon
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Ensemble habitat suitability modeling of stomatopods with Oratosquilla oratoria as an example
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作者 Lisha Guan Xianshi Jin +1 位作者 Tao Yang Xiujuan Shan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期93-102,共10页
Stomatopods are better known as mantis shrimp with considerable ecological importance in wide coastal waters globally. Some stomatopod species are exploited commercially, including Oratosquilla oratoria in the Northwe... Stomatopods are better known as mantis shrimp with considerable ecological importance in wide coastal waters globally. Some stomatopod species are exploited commercially, including Oratosquilla oratoria in the Northwest Pacific. Yet, few studies have published to promote accurate habitat identification of stomatopods, obstructing scientific management and conservation of these valuable organisms. This study provides an ensemble modeling framework for habitat suitability modeling of stomatopods, utilizing the O. oratoria stock in the Bohai Sea as an example. Two modeling techniques(i.e., generalized additive model(GAM) and geographical weighted regression(GWR)) were applied to select environmental predictors(especially the selection between two types of sediment metrics) that better characterize O. oratoria distribution and build separate habitat suitability models(HSM). The performance of the individual HSMs were compared on interpolation accuracy and transferability.Then, they were integrated to check whether the ensemble model outperforms either individual model, according to fishers’ knowledge and scientific survey data. As a result, grain-size metrics of sediment outperformed sediment content metrics in modeling O. oratoria habitat, possibly because grain-size metrics not only reflect the effect of substrates on burrow development, but also link to sediment heat capacity which influences individual thermoregulation. Moreover, the GWR-based HSM outperformed the GAM-based HSM in interpolation accuracy,while the latter one displayed better transferability. On balance, the ensemble HSM appeared to improve the predictive performance overall, as it could avoid dependence on a single model type and successfully identified fisher-recognized and survey-indicated suitable habitats in either sparsely sampled or well investigated areas. 展开更多
关键词 habitat suitability STOMATOPOD coastal fisheries predictor selection ensemble model
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Dual-objective pattern optimization method for land suitability zoning in mountain counties
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作者 WANG Lei WU Lian +1 位作者 ZHANG Wei JING Wen-li 《Journal of Mountain Science》 SCIE CSCD 2023年第1期209-226,共18页
As the basic administrative unit of China,counties have grown rapidly in recent years in the context of rapid urbanization,especially for counties located in mountainous areas.The drastic changes in land in mountainou... As the basic administrative unit of China,counties have grown rapidly in recent years in the context of rapid urbanization,especially for counties located in mountainous areas.The drastic changes in land in mountainous areas can easily cause irreversible damage to the sensitive ecological environment.Through the dual-objective suitability zoning of ecological and construction balance,regional sustainable land use patterns can be realized.In this study,Hantai District in Southern Shaanxi province,China,was chosen as the research area aiming at creating a balance between ecological supply and the development of construction in spatial planning.A dual-objective process evaluation system for ecological protection and construction development was proposed with 15 resistance factors selected from three attributes:natural ecology,economic society,and policy.The minimum resistance surface discrimination methods for ecological land and construction development land were proposed based on vertical space superposition and horizontal minimum cumulative resistance models.Finally,the land in Hantai District was divided into four development grades from the optimal angle of dual goals,i.e.,the construction core zone being 134.56 km^(2),the suitable construction zone 115.77 km2,the ecological buffer zone 153.74 km^(2),and the ecological control zone 151.93 km^(2),using the method combining resistance difference and threshold division.In addition,the development direction of each town under jurisdiction was identified.This study compensates for the deficiency of traditional methods that evaluate land only from a single vertical or horizontal process. 展开更多
关键词 Dual-objective pattern Land suitability zoning Minimum cumulative resistance model Mountain county Hantai District
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基于多元统计分析评价不同茶树品种的绿茶适制性 被引量:2
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作者 王欢欢 袁丽萍 +7 位作者 雷震东 杨淑雅 李玉川 周敬涛 覃信雪 余志 倪德江 陈玉琼 《食品科学》 EI CAS CSCD 北大核心 2024年第3期9-15,共7页
采用主成分分析和多元线性回归分析法考察不同茶区优选区域适制茶树品种的绿茶适制性。本研究以种植于同一区域的63个茶树品种鲜叶为原料,按同一加工工艺加工成烘青绿茶,分析其感官品质、主要理化品质(茶多酚、游离氨基酸、水浸出物和... 采用主成分分析和多元线性回归分析法考察不同茶区优选区域适制茶树品种的绿茶适制性。本研究以种植于同一区域的63个茶树品种鲜叶为原料,按同一加工工艺加工成烘青绿茶,分析其感官品质、主要理化品质(茶多酚、游离氨基酸、水浸出物和叶绿素)和色度值(L*、a*、b*),结合主成分分析和多元线性回归分析,评价供试品种的绿茶适制性及其主要影响因子。结果表明,不同品种绿茶叶绿素含量的变异系数最大(26.7%),其次是干茶色度值a*值(22.2%)、汤色(17.1%)和干茶色泽评分(16.2%)。各指标相关性分析表明,茶多酚含量与干茶色泽、汤色和叶底色泽之间,干茶叶绿素含量、|a*|值、b*值与干茶色泽之间,干茶叶绿素含量、|a*|与叶底色泽之间,干茶|a*|值、b*值与汤色之间极显著相关(P<0.01)。主成分分析结果表明,前5个主成分贡献率达76.895%,第1主成分贡献率为31.918%,主要指向色泽品质。通过前5个主成分构建评价模型,得到排名前10的品种包括:中茶108、乌牛早、平阳特早、蒙山9号、薮北种、福鼎大白、鸠坑16号、福鼎大毫、茂绿、龙井43。以主要理化品质和感官评价总分为对象进行多元线性回归分析,得到回归函数为:Y=68.668+5.174x,其中Y为感官评分总分,x为|a*|值,R2为0.313(P<0.001)。以此函数得到排名前10的品种与主成分分析结果高度一致,表明a*值是评定绿茶适制品种的重要指标,可作为绿茶适制品种筛选的重要依据。 展开更多
关键词 绿茶 茶树品种 适制性 综合评价
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Business Blockchain Suitability Determinants: Decision-Making through an Intuitionistic Fuzzy Method
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作者 Tomader Almeshal Jawad Berri +2 位作者 Tarifa Almulhim Areej Alhogail Emam Ahmed 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期1665-1690,共26页
Blockchain is one of the innovative and disruptive technologies that has a wide range of applications in multiple industries beyond cryptocurrency.The widespread adoption of blockchain technology in various industries... Blockchain is one of the innovative and disruptive technologies that has a wide range of applications in multiple industries beyond cryptocurrency.The widespread adoption of blockchain technology in various industries has shown its potential to solve challenging business problems,as well as the possibility to create new business models which can increase a firm’s competitiveness.Due to the novelty of the technology,whereby many companies are still exploring potential use cases,and considering the complexity of blockchain technology,which may require huge changes to a company’s existing systems and processes,it is important for companies to carefully evaluate suitable use cases and determine if blockchain technology is the best solution for their specific needs.This research aims to provide an evaluation framework that determines the important dimensions of blockchain suitability assessment by identifying the key determinants of suitable use cases in a business context.In this paper,a novel approach that utilizes both qualitative(Delphi method)and quantitative(fuzzy set theory)methods has been proposed to objectively account for the uncertainty associated with data collection and the vagueness of subjective judgments.This work started by scanning available literature to identify major suitability dimensions and collected a range of criteria,indicators,and factors that had been previously identified for related purposes.Expert opinions were then gathered using a questionnaire to rank the importance and relevance of these elements to suitability decisions.Subsequently,the data were analyzed and we proceeded to integrate multi-criteria group decision-making(MCGDM)and intuitionistic fuzzy set(IFS)theory.The findings demonstrated a high level of agreement among experts,with the model being extremely sensitive to variances in expert assessments.Furthermore,the results helped to refine and select the most relevant suitability determinants under three important dimensions:functional suitability of the use case,organizational applicability,and ecosystem readiness. 展开更多
关键词 Blockchain business blockchain use cases suitability assessment multi-criteria group decision-making fuzzy Delphi intuitionistic fuzzy set
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基于MaxEnt模型的北极村国家级自然保护区紫貂栖息地适宜性评价 被引量:7
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作者 刘艳华 刘磊 +6 位作者 陈红 刘小慧 王启蕃 刘鑫鑫 张子栋 张宇 周绍春 《生态学报》 CAS CSCD 北大核心 2024年第2期559-569,共11页
在人类支配的景观中,生境退化已经导致多个物种种群数量不断减少,分布范围不断缩减。紫貂(Martes zibellina)为国家Ⅰ级重点保护动物,种群数量稀少,开展栖息地适宜性研究工作对制定科学的栖息地保护计划至关重要。于2021年1月—2022年8... 在人类支配的景观中,生境退化已经导致多个物种种群数量不断减少,分布范围不断缩减。紫貂(Martes zibellina)为国家Ⅰ级重点保护动物,种群数量稀少,开展栖息地适宜性研究工作对制定科学的栖息地保护计划至关重要。于2021年1月—2022年8月在黑龙江省北极村国家级自然保护区采用样线调查法、足迹链跟踪、远红外相机监测综合收集到紫貂和猎物(雪兔)活动点信息。利用最大熵(MaxEnt)栖息地建模分析方法,首次在多个分辨率尺度背景下对紫貂种群的栖息地适宜性进行评价,研究结果表明:(1)利用ArcGIS 10.4重采样后在6个分辨率尺度(30m、60m、120m、240m、480m、960m)进行栖息地建模分析,基于主要栖息地变量因子对模型的贡献率及稳定性影响,并综合考虑研究区域面积,最终选定30m分辨率尺度作为紫貂栖息地最佳分析建模尺度,在30m分辨率尺度栖息地预测模型的曲线下面积(AUC)值为0.881;(2)研究发现猎物资源、植被类型和地形变量是影响紫貂栖息地适宜性的主要变量因子:雪兔出现概率较高、距草地与河流较近、海拔约400—600m、距常绿针叶林1.5km、距落叶针叶林约200m、坡向为50—250°的区域为紫貂的适宜栖息地;(3)栖息地适宜性分析表明,北极村国家级自然保护区紫貂适宜栖息地和次适宜栖息地面积共计23.66km2,约占保护区的17.2%,主要集中在保护区中部,而东部和西北部区域,栖息地破碎化较严重。基于模型结果与野外调查,提出了三条建议:(1)应严格控制人为活动,避免因人类干扰造成不适宜栖息地面积的持续扩大;(2)建立生态廊道促进保护区西部与中部紫貂种群进行个体交流,降低紫貂种群局部区域灭绝概率;(3)对东部地区破碎化的栖息地进行修复,扩大东部适宜栖息地面积,使破碎化的栖息地连接为整体。为分布于我国最北端的紫貂种群恢复创造条件,这对于构建该地区相对稳定的生物多样性保护空间格局有着重要意义。 展开更多
关键词 紫貂 最大熵模型 最优分辨率尺度 栖息地适宜性
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基于XGBoost算法的可恢复耕地宜耕性评价——以湘阴县为例 被引量:2
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作者 刘敏 周健 +4 位作者 胡月明 张林 赵清林 秦雅静 陈瑗瑗 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第1期49-60,共12页
为科学有序开展可恢复耕地资源的整治,本研究提出一种基于XGBoost算法的可恢复耕地的宜耕性评价方法。选取自然条件、区位条件、社会经济状况以及工程条件等4个方面的因素,涉及海拔高程、坡度级别、国家自然等、集块面积、国家经济等、... 为科学有序开展可恢复耕地资源的整治,本研究提出一种基于XGBoost算法的可恢复耕地的宜耕性评价方法。选取自然条件、区位条件、社会经济状况以及工程条件等4个方面的因素,涉及海拔高程、坡度级别、国家自然等、集块面积、国家经济等、地块形状等36项影响因素为自变量,以现状可恢复耕地和耕种耕地二分类为因变量,分析各项影响因素对耕地宜耕性评价的重要程度,并进一步结合皮尔逊共线性分析和指标关联性分析,最终得到21项影响因素及其权重P值,优化后影响因素的权重P值相对稳定,其中自然因素对可恢复耕地宜耕性的影响权重最大,区位因素和工程因素权重次之,社会经济因素的权重最小。经过验证发现,预测耕种情况与实际耕种情况的符合率高达91.87%,且具有良好的泛化能力和鲁棒性,预测效果良好。借助上述模型预测得到的湘阴县可恢复耕地地块的宜耕潜力,形成如下认识:全县中西部平原区可恢复耕地宜耕潜力明显优于东部丘陵山区;可恢复耕地中未耕种和即可恢复地块的宜耕潜力高于工程恢复类地块,这些地块均属于良好的整治地块,可优先整治恢复为耕地;从可恢复耕地具体地类来看,坑塘和养殖坑塘类可恢复耕地的宜耕潜力最大,其次为其他林地类可恢复耕地;在耕地整治过程中,应结合可恢复耕地的宜耕性评价,合理有序地开展可恢复耕地的整治;此外,应开展精细化的耕地“非粮化”监测,实施差异化补偿政策,以遏制耕地“非粮化”。 展开更多
关键词 XGBoost 可恢复耕地 宜耕性 宜耕潜力 湘阴县
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Cold-Weather Crop Suitability Modelling
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作者 Kamille Lemieux Nana-Agyei O. Afriyie +2 位作者 Shane Furze Patrick Toner Paul A. Arp 《Open Journal of Soil Science》 2023年第10期431-455,共25页
This article presents ArcGIS Pro workflow results aimed at rating and mapping cold-weather crop suitability from 0% to 100% at 1-m elevation resolution for the Province of New Brunswick (NB). This rating accounts for ... This article presents ArcGIS Pro workflow results aimed at rating and mapping cold-weather crop suitability from 0% to 100% at 1-m elevation resolution for the Province of New Brunswick (NB). This rating accounts for variations by soil conditions (texture, coarse fragments, depth, calcareousness, drainage, slope), growing degree days (GDD) and frost-free days (FFD) from within fields to across regions. The ratings so produced reflect a significant part of farm and farm/woodlot property assessment values as these also vary by area and building footprint. While the soil properties for texture, coarse fragments, depth, and calcareousness vary by NB soil association mapping units, within-field suitabilities also vary by slope from flat to steep and by drainage as it correlates across the terrain by depth-to-water (DTW) from very poor to poor, imperfect, moderate, well and excessive. Areas marked by 1.5 10% have low to no suitability because of slope-increased soil erosion and trafficability risks. The number of growing-degree and frost-free days across NB were rated to be sufficient for cold weather cropping, except marginally so at the high-elevation locations. 展开更多
关键词 Crop suitability Rating TOPOGRAPHY Climate Soil Properties Property Values Regression Analysis
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Business Clothing For Females: Suitability For Effective Workplace Job Performance in Nigeria
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作者 Azonuche Juliana Ego 《Journal of International Education and Practice》 2023年第2期37-45,共9页
The study investigated business clothing for females that are suitable for effective workplace job performance in Nigeria.It identified fabric characteristics of females’business clothing already used;fabric characte... The study investigated business clothing for females that are suitable for effective workplace job performance in Nigeria.It identified fabric characteristics of females’business clothing already used;fabric characteristics needed and deign style preference suitable for females’business clothing for workplace job performance.The study was guided by four research questions and two hypotheses.Population was 4,806 female civil servants in Delta state,Nigeria.Multi-stage sampling technique was utilized to select 136 females.Structured questionnaire was employed to collect data and descriptive statistics and t-test were used for data analysis.Finding showed that cotton,nylon,lacra fabrics,light and medium fabric weight,blue,black,gray,colors,cool texture,rough,smooth surface plain,stripe and flowered design among others were fabric characteristics of business clothing are being used in workplace.But prefer and need cotton,nylon,lacra,light weight,black,blue,gray,brown colours,cool,plain,surface fabrics.Net,organza,heavy weight,white,yellow,toweling fabrics were not preferred.Findings further showed that straight gown,waist flared and gathered gowns,skirt,blouse and suit/jacket,straight,shirt,long sleeves,garment with or without collar,below knee length,peter and convertible collars,among others were highly preferred design styles of clothes.In conclusion,office workers determine what they wear to perform workplace daily jobs promotes self-confidence,comfort,professional worth and productivity.It was recommended that female employees should not downplay appropriate work attires for comfort and organizational productivity to satisfy fashion trends. 展开更多
关键词 Business Clothing Females suitability WORKPLACE Job Performance
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基于三维地质模型的西咸新区地下空间开发适宜性评价 被引量:1
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作者 李林 曾磊 +2 位作者 董英 张戈 朱立峰 《地质与勘探》 CAS CSCD 北大核心 2024年第1期197-206,共10页
地下空间开发地质适宜性评价是合理进行地下空间开发、降低开发地质风险的重要手段。传统的评价方法没有考虑地下空间复杂的垂向变化,因而无法满足越来越精确的地下空间规划要求。本文以西咸新区沣东沣西为例,结合该区地质地貌背景、工... 地下空间开发地质适宜性评价是合理进行地下空间开发、降低开发地质风险的重要手段。传统的评价方法没有考虑地下空间复杂的垂向变化,因而无法满足越来越精确的地下空间规划要求。本文以西咸新区沣东沣西为例,结合该区地质地貌背景、工程地质特征、水文地质条件、不良地质作用以及地下空间开发现状等特点,建立地下空间开发地质适宜性评价因子体系;利用三维精细化剖分的评估单元为载体,综合使用多种三维空间分析方法从多要素地质模型中定量或定性提取各项指标,运用层次分析法模型开展研究区地下空间开发适宜性评价。评价结果表明:研究区60m以浅地下空间开发利用条件优越,总体适宜开发建设。浅层空间易受文物保护区、地面水体、活动断裂影响,中层空间受城市建成区既有设施及地下构筑物影响较大,深部地下空间主要受断裂影响。该方法能够精细刻画地下空间在垂向上的差异,评估过程与结果能够立体透明化表达,能够定性、定量地为地下空间开发利用提供辅助决策,以达到资源保护优先、协同开发的开发利用格局。 展开更多
关键词 地下空间开发利用 地质适应性评价 三维地质模型 西咸新区
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