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Diversity of Orchids in Terms of Their Distribution, Uses and Conservation in Annapurna Conservation Area of Nepal
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作者 Babu Lal Tiruwa Basu Dev Neupane +2 位作者 Rabin Kadariya Chiranjibi Prasad Pokheral Bijaya Pant 《American Journal of Plant Sciences》 CAS 2024年第6期422-440,共19页
The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enou... The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enough yet thus making the need for ambitious research to be carried out. Previous study only included 81 species of orchids within ACA. This study aims to update the record of species and genera richness in the ACA. In total 198 species of orchids, belonging to 67 genera (40% and 62% of the total recorded orchid species and genera in Nepal) has been recorded in ACA. This represents an increase of 144% in species and 56% in genera over the previous data. Out of the 198 species, 99 were epiphytes, 6 were holomycotrophic and 93 were terrestrial. Among the 67 genera, Bulbophyllum (17) species were dominant, followed by Dendrobium (16), Herminium (10), Coelogyne, Plantanthera (9 each), Eria, Habenaria, Oberonia (8 each), Calanthe (7), and Liparis (6). Fifty-six species were found to be ornamentally significant and 85 species medicinally significant. 展开更多
关键词 ORCHIDS Annapurna Conservation area DIVERSITY DISTRIBUTION USES
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Research Progress of the Planning Methods of Prior Conservation Areas
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作者 汤燕 陶国庆 谷勋刚 《Agricultural Science & Technology》 CAS 2016年第2期398-404,共7页
The planning of prior conservation areas is an important part of nature re- serve system, :it is of great significance for biodiversity conservation. The methods of priority planning include hot-spots analysis, gap a... The planning of prior conservation areas is an important part of nature re- serve system, :it is of great significance for biodiversity conservation. The methods of priority planning include hot-spots analysis, gap analysis, systematic conservation planning analysis and multi-criteria decision analysis. The key issues of priority area planning include the determination of the protect objects, the analyses of the protec- tion value and protection cost, the win-win development of protection and economy, and the changes of the management strategies of the protected areas. In this study, the features and research progress of different conservation methods were analyzed, and based on the discussion on the key issues of the planning of the protected areas, the application prospect of different methods was analyzed. 展开更多
关键词 The planning of the protected areas Prior conservation areas System- atic conservation planning Multi-criteria decision analysis: Protection value
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Gully Erosion Regionalization of Black Soil Area in Northeastern China 被引量:13
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作者 YANG Jiuchun ZHANG Shuwen +3 位作者 CHANG Liping LI Fei LI Tianqi GAO Yan 《Chinese Geographical Science》 SCIE CSCD 2017年第1期78-87,共10页
Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fe... Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fertile farmland there. Regionalization of gully erosion can reveal the spatial distribution and regularity of the development of gully erosion. Based on the eco-geographical regional background features of the black soil area, this study combined the regionalization with influencing factors of the development of gully erosion. GIS spatial analysis, geostatistical analysis, spatial statistics, reclassification, debris polygon processing and map algebra methods were employed. As a result, the black soil area was divided into 12 subregions. The field survey data on type, length, volume and other characteristics indicators of gully erosion were used to calibrate the results. Then the features of every subregion, such as where the gully erosion is, how serious it is, and why it happens and develops, were expounded. The result is not only an essential prerequisite for gully erosion surveys and monitoring, but also an important basis for gully erosion prevention. 展开更多
关键词 regionalization gully erosion soil and water conservation black soil area northeastern China
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Analysis of the Capacity of Wellspring Conservation in Limestone Areas of Jinan 被引量:1
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作者 Zhou Baohua Li Daqiu 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第2期47-54,共8页
Spring water in the city of Jinan conies from the limestone areas. Understanding the capacity of wellspring conservation is a critical point to resume the perennial spewing of the spring water. The vegetation, soil, a... Spring water in the city of Jinan conies from the limestone areas. Understanding the capacity of wellspring conservation is a critical point to resume the perennial spewing of the spring water. The vegetation, soil, and other natural and human aspects related to the conservation are studied by using the methods of geographic information systems (GIS), remote sensing (RS), and field investigation. In the end, suggestions for administration and planning as well as countermeasures are put forward. 展开更多
关键词 wellspring conservation conservation area of ecological function limestone areas of Jinan
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Correlates of avifaunal diversity along the elevational gradient of Mardi Himal in Annapurna Conservation Area,Central Nepal 被引量:1
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作者 Naresh Pandey Laxman Khanal Mukesh Kumar Chalise 《Avian Research》 CSCD 2020年第3期201-214,共14页
Background:Patterns of biological diversity and richness can vary along the elevational gradients among mountain systems making it difficult to conclude the general pattern.The drivers of such pattern are also poorly ... Background:Patterns of biological diversity and richness can vary along the elevational gradients among mountain systems making it difficult to conclude the general pattern.The drivers of such pattern are also poorly known in the southern flank of the Himalaya due to limited studies.Therefore,we assessed the species richness,seasonal patterns and drivers of avian diversity along an elevational gradient on Mardi Himal trekking trail,a newly open tourist route in Annapurna Conservation Area of the central Himalaya.Methods:Two surveys(winter and summer seasons of 2019)were conducted from the bank of Seti-Gandaki River confluence(1030 m above sea level,asl)up to the Low Camp(3050 m asl)of the Mardi Himal.The point count method was employed in every 100 m rise in the elevation.Diversity indices were calculated and bird abundance data on species,sites,seasons and environmental variables were analyzed.Generalized linear model,polynomial regression and ordinary least square regression were performed to examine the importance of environmental factors in shaping the avian richness pattern.Results:A total of 673 individuals of birds belonging to 112 species,of which 72 in winter and 80 in summer,were recorded.We observed a hump-shaped pattern of the overall species richness along the elevational gradient.The richness pattern remained consistent even when explored by season,for winter and summer separately.Diversity indices were found higher during the summer.Elevation and mean monthly temperature in both seasons showed non-linear relation with avian species richness.Precipitation exhibited positive association in summer whereas the same in winter was negatively correlated with avian species richness.Distance to the nearest water source and the nearest human settlement were negatively correlated with the richness of birds.Small-ranged and insectivorous birds were under the strong influence of gradients on climatic variables like temperature and precipitation.Conclusions:We conclude that the combined effects of multiple factors such as area,gradients of climate(i.e.temperature and precipitation),resource availability and disturbance play an important role in bird diversity and richness pattern along an elevational gradient of a montane environment in Mardi Himal. 展开更多
关键词 Annapurna Conservation area Avian richness Central Himalaya ELEVATION
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Factors That Influence Local Community Participation in Tourism in Murchison Falls Conservation Area
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《Journal of Environmental Science and Engineering(A)》 2017年第4期209-223,共15页
Community's participation is fundamental in understanding the factors that influence their access to and utilization of tourism resources. It is a plausible way of involving local communities in the planning and mana... Community's participation is fundamental in understanding the factors that influence their access to and utilization of tourism resources. It is a plausible way of involving local communities in the planning and management of the available resources for their sustainability. This study examined the socio-economic characteristics of the households in Murchison Falls Conservation Area to understand how they influence their participation in tourism and eventually enhance household welfare. Using household survey and key informant interviews, data were collected on demographic and socio-economic characteristics of the respondents and analyzed using Binomial Logit Regression in order to show the factors that influence participation of households in tourism. It was found that the households' characteristics significantly influenced their participation. In particular, level of education (r = 0.824), engagement in farm labor (r = 0.651), provision of services to the tourists (r = 0.841), income (r = 0.83) and landholding (r = 0.689) significantly influenced households' participation in tourism. On the other hand, age (r = 0.59) and period of residence (r = 0.430) did not significantly influence the households' participation in tourism. These results suggest that a clear understanding of the households' socio-economic characteristics is a vital step in engaging them meaningfully in tourism activities meant to enhance their livelihoods. Equally important is the need for tourism managers and local government leaders to consider these characteristics when designing policies and strategies to enhance community involvement and management of tourism at a conservation area level. 展开更多
关键词 Local community PARTICIPATION TOURISM conservation area.
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Tourism Development Models Based on Ecological Utilization and Protection of Water Conservancy Scenic Areas
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作者 OUYANG Jugen 《Journal of Landscape Research》 2014年第5期47-48,50,共3页
In view of major confl icts between ecological conditions of scenic areas and tourism development, tourism development models and approaches of six major water conservancy scenic areas were summarized on the basis of ... In view of major confl icts between ecological conditions of scenic areas and tourism development, tourism development models and approaches of six major water conservancy scenic areas were summarized on the basis of investigating interaction mechanism, ecological utilization and protection of scenic areas, including reservoir development and construction model, wetland development and construction model, natural river and lake development and construction model, city river and lake development and construction model, irrigated area development and construction model, water and soil conservation development and construction model. The research fruits are of instructive signif icance for the management and development of scenic areas. 展开更多
关键词 Water conservancy scenic area ECOLOGY TOURISM Interaction mechanism
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Peoples’ Perception and Conservation of Dactylorhiza hatagirea (D. Don) Soóin Manaslu Conservation Area, Central Nepal
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作者 Bikram Pandey Arbindra Timilsina +6 位作者 Binita Pandey Chhabi Lal Thapa Kamal Bahadur Nepali Pradeep Neupane Resham Thapa Sunil Kumar Gaire Mohan Siwakoti 《American Journal of Plant Sciences》 2016年第12期1662-1672,共11页
The present study analyzes the information and perception of the local community of Samagaun VDC, Manaslu Conservation Area Project (MCAP) regarding Dactylorhiza hatagirea (D. Don) Soó (Orchidaceae). We assessed ... The present study analyzes the information and perception of the local community of Samagaun VDC, Manaslu Conservation Area Project (MCAP) regarding Dactylorhiza hatagirea (D. Don) Soó (Orchidaceae). We assessed the local peoples’ perception on its population status, its availability, factors causing its decline and management practices of this terrestrial orchids. A pre-designed questionnaire was used to gather information targeting the age group between 25 and 60 years (n = 75, 45 male and 30 female). Most of the informants (76%) believe that the abundance of this orchid is declining. Over grazing of domestic animals, over harvesting and lack of awareness among the local community were determined to be the major causes of decline of D. hatagirea in the study area. Protection measures as prescribed by the informants were control grazing, raising awareness among the individuals and sustainable harvestings for the long-term conservation of the species. Systematic management plans that incorporate the participation of local individuals and prioritization of their views will be applicable for the proper conservation of the species. 展开更多
关键词 Local Perceptions Conservation and Management ORCHID Dactylorhiza hatagirea Samagaun VDC Manaslu Conservation area
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Spatial Analysis of Federal Protected Areas and Priority Areas for Biodiversity Conservation in Brazil
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作者 Valdir Adilson Steinke Sandra Maria da Silva Barbosa +3 位作者 Venicius Juvencio de Miranda Mendes Vinicius Galvao Zanatto Gabriella Emilly Pessoa Gustavo Bayma 《Journal of Geographic Information System》 2018年第6期718-734,共17页
This study presents a spatial analysis of priority areas for biodiversity conservation (PABCs) in Brazil and their coverage by federal protected areas as an indicator of the level of protection afforded to biodiversit... This study presents a spatial analysis of priority areas for biodiversity conservation (PABCs) in Brazil and their coverage by federal protected areas as an indicator of the level of protection afforded to biodiversity in the country and the convergence of environmental protection policies in the sphere of federal government. Georeferenced data were processed using a geographic information system, enabling the calculation of areas, analyses of superimpositions, localizations, and the obtainment of other information using spatial features manipulated in this system. A comparative analysis is done of the PABCs mapped in two periods (2003 and 2007) to ascertain the evolution of this public policy instrument in detecting environmental priorities in protected areas. The improved coverage of PABCs by protected areas in the more recent mapping indicates a good convergence of environmental policies, which are enhanced by technical improvements to mapping procedures and methods for identifying such areas. As a result, the priority areas for biodiversity conservation could become a protected area regulated and recognized by the federal government. 展开更多
关键词 Protected areas ENVIRONMENT Public Policies Spatial Information GEOPROCESSING Priority areas for Biodiversity Conservation
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Revitalization of Historic Conservation Areas:The Landscape Design for Yongqing Fang Phase III in Guangzhou,China
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作者 Hu SUN 《景观设计学(中英文)》 CSCD 2024年第5期100-103,共4页
1 Introduction The regeneration and revitalization of historic conservation areas is not only of significant importance for the transformation of urban spaces but also has become a widely discussed topic in recent urb... 1 Introduction The regeneration and revitalization of historic conservation areas is not only of significant importance for the transformation of urban spaces but also has become a widely discussed topic in recent urban renewal efforts.The Yongqing Fang,sitting in the Enning Road 1 Introduction The regeneration and revitalization of historic conservation areas is not only of significant importance for the transformation of urban spaces but also has become a widely discussed topic in recent urban renewal efforts.The Yongqing Fang,sitting in the Enning Road Historic Conservation Area in Guangzhou,China is renowned as“the most beautiful old-style street in Guangzhou.”Through its staged redevelopment since 2016,Yongqing Fang has turned into an attractive destination with distinctive Lingnan(Cantonese)characteristics,providing places for specialty dining,creative industries,cultural performances,recreational and cultural experiences,etc.This renewal project has also stimulated the coordinated development of the surrounding areas. 展开更多
关键词 Historic Conservation area Urban Public Space Urban Design Urban Renewal Cultural Landscape Landscape Design
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Ecological Risk of Heavy Metals in Sediment Around Techeng Island Special Marine Reserves in Zhanjiang Bay 被引量:1
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作者 ZHANG Cuiping ZHENG Zhaoyong +3 位作者 YAO Shaohui JIA Houlei XIAN Xianheng WANG Liang 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第3期561-568,共8页
The concentrations of five metals(Cu, Pb, Zn, Cd and Hg) were measured in sediments obtained before and after the establishment of Techeng Island Special Marine Reserves(TCISMR) in Zhanjiang Bay to evaluate the ecolog... The concentrations of five metals(Cu, Pb, Zn, Cd and Hg) were measured in sediments obtained before and after the establishment of Techeng Island Special Marine Reserves(TCISMR) in Zhanjiang Bay to evaluate the ecological risk of heavy metals. The results showed that average values of potential ecological risk indexes of heavy metals at all stations increased slightly from 32.09 to 30.54 after establishment of TCISMR. Optimal semivariance simulation showed that the contents of five heavy metals have strong spatial correlations in August 2010(before), while this correlations weakened in April 2013(after establishment of TCISMR), suggesting that the main sources of heavy metals changed. The Hakanson Risk Index(HRI) values in Donghai levee, central and southern parts of Zhanjiang harbor were high up to 60.13 and 46.46, respectively. And Zhanjiang Bay Channel, the areas around special marine reserves, the artificial reef areas and mangrove areas at south of Techeng Island are the areas with low ecological risk and high ecological value, which should be treated as the prior ecological protection areas. Our study provided a priority control pattern of heavy metal pollution in TCISMR, which greatly benefits the sustainable development and resource protection in Zhanjiang Bay. 展开更多
关键词 Techeng Island Special Marine Reserves surface sediment heavy metals potential ecological risk prior conservation area
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Application of SEDEA to evaluation of degree of harmony between water resources and economic development 被引量:1
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作者 Jun MA Chui-yong ZHENG 《Water Science and Engineering》 EI CAS 2011年第1期110-120,共11页
This paper introduces the method of data envelopment analysis (DEA) for evaluation of the degree of harmony between water resources and economic development of the water conservancy area of China's South-to-North W... This paper introduces the method of data envelopment analysis (DEA) for evaluation of the degree of harmony between water resources and economic development of the water conservancy area of China's South-to-North Water Diversion Project (SNWDP). For this evaluation, a super-efficiency DEA (SEDEA) model was developed based on the super-efficiency method. To verify the applicability of the SEDEA model, both the SEDEA model and a normal-efficiency DEA (NEDEA) model were used to evaluate the degree of harmony between water resources and economic development of typical cities in the SNWDP water conservancy area. The results show that the SEDEA model ranks the degree of harmony of typical cities more efficiently than the NEDEA model, and thus can better evaluate the degree of harmony between water resources and economic development of different cities than the NEDEA model. Furthermore, the SEDEA model can be applied as an operational research tool in regional water resources management. 展开更多
关键词 degree of harmony super-efficiency DEA model water conservancy area South-to-North Water Diversion Project
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Surrogacy of bird species in systematic conservation planning and conservation assessments in Yunnan Province,China
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作者 ZHOU Jian YANG Fei-ling +4 位作者 ZHONG Zi-jie ZHANG Ji LENG Xian YE Jin WU Rui-dong 《Journal of Mountain Science》 SCIE CSCD 2022年第10期2861-2873,共13页
Bird diversity is often used as surrogates for other species diversity,but there is a limited understanding of the extent of this surrogate in identifying representative priority conservation areas(PCAs).We used Yunna... Bird diversity is often used as surrogates for other species diversity,but there is a limited understanding of the extent of this surrogate in identifying representative priority conservation areas(PCAs).We used Yunnan Province in China as a case to measure the surrogacy of birds in systematic conservation planning.Here,we collected distribution records of mammals,amphibians,reptiles,and birds from public databases and literature,and applied systematic conservation planning methods to identify PCAs.We targeted four taxonomic groups at conservation targets of 17%,31%,and 50%of the total study area,and used the Jaccard similarity index to evaluate the surrogate extent of bird PCAs for the other three groups.Then,we overlapped different portfolios of PCAs with six categories of protected areas(PAs)in Yunnan,calculated the protection rates,and evaluated the effect of sustainable-use PAs on improving the protection rate of strict Nature Reserves.The results showed that bird PCAs generally had the highest surrogacy for representing PCAs of the other three taxa.At the 50%conservation target,the Jaccard indices between birds and the other taxa reached about 0.50.Moreover,amphibian PCAs had a good surrogacy for conserving reptiles,with a Jaccard index of 0.30,0.44 and 0.51 at the 17%,31%and 50%conservation targets,respectively.The existing PA system had quite low coverages for PCAs of these four taxa,and the average protection rates were 22.97%,19.78%and 16.52%at the three levels of conservation targets,respectively.The sustainable-use PAs can greatly complement the strict Nature Reserves by achieving average increased PA coverages of 10.00%,9.20%and 7.90%at the three conservation targets.Our findings provide a basis for surrogate-based conservation planning for areas with insufficient biodiversity information. 展开更多
关键词 Biodiversity surrogates Priority conservation areas Protected areas Systematic conservation planning Threatened species YUNNAN
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Spatial-temporal shifting patterns and in situ conservation of spotted seal(Phoca largha)populations in the Yellow Sea ecoregion 被引量:2
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作者 Hongfei ZHUANG Fei SHAO +7 位作者 Chao ZHANG Wancai XIA Shouqiang WANG Fangyuan QU Zongling WANG Zhichuang LU Linlin ZHAO Zhaohui ZHANG 《Integrative Zoology》 SCIE CSCD 2024年第2期307-318,共12页
Understanding the habitat shifting pattern is a prerequisite for implementing in situ conservation of migratory species.Spotted seals(Phoca largha)inhabiting the Yellow Sea ecoregion(YSE)comprise a small population wi... Understanding the habitat shifting pattern is a prerequisite for implementing in situ conservation of migratory species.Spotted seals(Phoca largha)inhabiting the Yellow Sea ecoregion(YSE)comprise a small population with independent genes and represent a charismatic flagship species in this region.However,this population has declined by 80%since the 1940s,and increased support from the countries around the YSE is urgently needed to address the potential local extinction risk.A time-series niche model and life-history weighted systematic conservation planning were designed on the basis of a satellite beacon tracking survey(2010–2020)of the YSE population.The results showed clustering and spreading shifting patterns during the breeding and migratory seasons,respectively.The closed-loop migration route formed in the YSE indicated that this population might be geographically isolated from populations in other breeding areas around the world.The conservation priority area(CPA),with an area of 19632 km^(2)(3.58%of the total YSE area),was the most effective response to the potential in situ risk.However,nearly 80%of the CPA was exposed outside the existing marine protected areas(MPAs).Future establishment of MPAs in China should strategically consider the conservation gap identified herein,and it is recommended for Korea’s closed fishing season to be spatially set in the western Korean Peninsula from May to August.This study also exemplified that the lack of temporal information would lead to the dislocation of niche modeling for migratory species represented by spotted seals.Attention should be paid to protecting small and migratory populations in marine biodiversity conservation planning. 展开更多
关键词 conservation priority area marine protected area MIGRATION seasonal management spotted seal
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Stability analysis of reef fish communities based on symbiotic graph model
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作者 Danfeng Zhao Yaru Lou +2 位作者 Wei Song Dongmei Huang Xiaoliang Wang 《Aquaculture and Fisheries》 CSCD 2024年第6期1007-1017,共11页
The community stability of coral reefs and fish is the focus of ecological monitoring of coral reefs.Among them,the realization of effective metrics of variations in reef fish communities(i.e.,the combined communities... The community stability of coral reefs and fish is the focus of ecological monitoring of coral reefs.Among them,the realization of effective metrics of variations in reef fish communities(i.e.,the combined communities of coral reefs and fish)is important for analyzing the stability of communities as well as maintaining the ecological balance of coral reefs.Based on coral reef and fish data collected at St.John’s Island from 2004 to 2010,this study proposes a symbiotic graph modeling method to express the biological relationships of reef fish communities,and a Pyramid Match graph kernel method for fusing Attributes(PMA)to quantify community fluctuations to measure interannual variability of communities.The results showed that the community similarity was low in 2006,2007,and 2008.The total coral cover rate in the study area decreased by 32.04% from 2006 to 2007 and increased by 24% in 2008.The total number of fish fell from 3780 in 2006 to 2596 in 2007 and rose to 6249 in 2008.Among them,the proportion of herbivorous fish decreased to 30.84% in 2007.Furthermore,we have combined the Louvain algorithm with the proposed PMA method to effectively identify the regions that should be prioritized for protection.Experiments were conducted on real datasets with good results,demonstrating the potential of the proposed method to assist in the analysis of community stability and identification of priority conservation areas. 展开更多
关键词 Reef fish community Community stability Community variation Symbiotic graph model Graph kernel Conservation area
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Identifying priority areas for conservation in the lower Yellow River basin from an ecological network perspective 被引量:1
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作者 Jieming Kang Chunlin Li +2 位作者 Meirui Li Teng Zhang Baolei Zhang 《Ecosystem Health and Sustainability》 SCIE 2022年第1期486-501,共16页
Taking the lower Yellow River basin as the study area,this study aims to construct ecological networks to mitigate the negative impacts of rapid urbanization on the ecosystem.Ecological sources were identified based o... Taking the lower Yellow River basin as the study area,this study aims to construct ecological networks to mitigate the negative impacts of rapid urbanization on the ecosystem.Ecological sources were identified based on morphological spatial pattern analysis(MSPA),habitat quality and landscape connectivity.The ecological resistance surface was constructed and corrected by integrating natural and anthropogenic factors.The spatial range of ecological corridors and some of their key nodes were identified based on circuit theory.The ecological network(EN)was finally optimized using a similarity search and cost connectivity modules.The results show that the optimized ecological network structure is more stable than before.The EN includes 23 ecological sources with a total area of 5464.8 km^(2)and 30 ecological corridor clusters with a total area of 2205.92 km^(2).Through the internal landscape heterogeneity of the corridor,28 ecological node areas and 75 barrier areas were identified as key protection and restoration areas,with a total area of 78.44 km^(2)and 372.79 km^(2),respectively.Through the construction and optimization of EN,this study identifies key areas for promoting ecological sustainability and provides a useful framework for coordinating regional ecological conservation and economic development. 展开更多
关键词 Ecological network ecological sources and corridors conservation and restoration priority areas circuit theory
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Numerical Simulation of Free Surface by an Area-Preserving Level Set Method
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作者 Tony W.H.Sheu C.H.Yu 《Communications in Computational Physics》 SCIE 2012年第4期1347-1371,共25页
We apply in this study an area preserving level set method to simulate gas/water interface flow.For the sake of accuracy,the spatial derivative terms in the equations of motion for an incompressible fluid flow are app... We apply in this study an area preserving level set method to simulate gas/water interface flow.For the sake of accuracy,the spatial derivative terms in the equations of motion for an incompressible fluid flow are approximated by the fifthorder accurate upwinding combined compact difference(UCCD)scheme.This scheme development employs two coupled equations to calculate the first-and second-order derivative terms in the momentum equations.For accurately predicting the level set value,the interface tracking scheme is also developed to minimize phase error of the first-order derivative term shown in the pure advection equation.For the purpose of retaining the long-term accurate Hamiltonian in the advection equation for the level set function,the time derivative term is discretized by the sixth-order accurate symplectic Runge-Kutta scheme.Also,to keep as a distance function for ensuring the front having a finite thickness for all time,the re-initialization equation is used.For the verification of the optimized UCCD scheme for the pure advection equation,two benchmark problems have been chosen to investigate in this study.The level set method with excellent area conservation property proposed for capturing the interface in incompressible fluid flows is also verified by solving the dam-break,Rayleigh-Taylor instability,two-bubble rising in water,and droplet falling problems. 展开更多
关键词 Level set method phase error upwinding combined compact scheme HAMILTONIAN symplectic Runge-Kutta area conservation property
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The Ownership of Heritage Area with the Conservation Management Apporach——Taking Tianzifang and The Rock as Case Studies
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作者 王婥约 《环球市场信息导报》 2016年第34期101-104,共4页
关键词 Taking Tianzifang and The Rock as Case Studies The Ownership of Heritage area with the Conservation Management Apporach
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Separating the effects of two dimensions on ecosystem services:Environmental variables and net trade-offs
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作者 ZUO Liyuan JIANG Yuan +2 位作者 GAO Jiangbo DU Fujun ZHANG Yibo 《Journal of Geographical Sciences》 SCIE CSCD 2023年第4期845-862,共18页
Spatial and temporal changes in ecosystem services(ESs)are driven by two types of factors:environmental factors and trade-offs/synergies between services.In the ecological conservation red line(ECRL)area,in which nati... Spatial and temporal changes in ecosystem services(ESs)are driven by two types of factors:environmental factors and trade-offs/synergies between services.In the ecological conservation red line(ECRL)area,in which national ecological security and social sustainable development are guaranteed,it is particularly important to clarify the driving mechanism of ESs for the management of ecosystems.In this study,soil conservation,water yield,and carbon sequestration in Beijing’s ECRL area are quantified,and GeoDetector is used to identify the factors influencing the trade-offs/synergies between ESs.Moreover,partial correlation analysis is used to calculate the net trade-offs/synergies and compare them with the extent to which environmental variables contribute to ESs.The results are as follows:environmental variables and trade-offs/synergies have different effects on the changes in ESs,and their interactions can enhance the determinative power of the corresponding individual variable.The land use intensity is an extremely important factor affecting the trade-offs/synergies between the three services,indicating that rational land use planning in Beijing’s ECRL area is crucial for avoiding the negative impacts of trade-offs and enabling coordinated optimization of ESs.After the elimination of the cross-influence of environmental variables,the trade-offs/synergies change significantly,and the impact of environmental variables on ESs is compared with the net trade-offs/synergies.Environmental variables are the driving forces of the spatiotemporal changes in soil conservation.Precipitation and carbon sequestration have similar effects on water yield.Spatiotemporal changes in carbon sequestration are closely related to the other two services,with smaller influences from environmental variables. 展开更多
关键词 ecosystem services trade-offs and synergies driving mechanisms quantitative separation ecological conservation red line area
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The challenge of combining variable retention and prescribed burning in Finland 被引量:1
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作者 Henrik Lindberg Pekka Punttila Ilkka Vanha-Majamaa 《Ecological Processes》 SCIE EI 2020年第1期46-57,共12页
Historically,wildfires have played an important role in forest dynamics in Fennoscandia.In Finland,the annually burned area has diminished in recent decades.This has led to a decline of fire-adapted habitat types and ... Historically,wildfires have played an important role in forest dynamics in Fennoscandia.In Finland,the annually burned area has diminished in recent decades.This has led to a decline of fire-adapted habitat types and species,many of which have become red-listed.In Fennoscandia,there is a long tradition of silvicultural burnings to enhance tree regeneration.Recently,prescribed burnings have been modified for biodiversity goals following the recommendations that have emerged from ecological research.Prominent biodiversity gains can be obtained by combining sufficient retention levels with burnings.Consequently,burning and retention have been recommended by recent national red-list assessments,strategies,and forest-management guidelines,and they have been adopted in forest-certification standards in Finland.Contrary to these recommendations,the opposite development has taken place:(1)the ecological efficiency of the criterion concerning prescribed burning in the PEFC forestcertification standard has been impaired,(2)state funding to encourage private forest owners to apply prescribed burning was reduced significantly,and(3)prescribed burnings have been abandoned altogether in commercial state-owned forests.Traditional burnings with variable retention have also been partially replaced with burning of small retention-tree groups.This new method is less risky and cheaper,but its ecological benefits are questionable because small-sized fires produce much smaller areas of burned forest soil with less fire-affected wood than traditional silvicultural burnings.Generally,the widely accepted goal to increase burnings with retention appears difficult to achieve and would require stronger political will and economic support from the government.We identified several actions that could improve the weakened situation of fire-dependent biodiversity and recommend the following:(1)setting a clear goal and ensuring sufficient funding for the burnings—including restoration burnings in conservation areas—and targeting these to specific fire-continuum areas with sufficient retention to ensure the continuity of fire-affected habitats at landscape level;(2)renewing the current subsidizing policies to encourage private landowners to perform prescribed burnings in regeneration areas after final fellings,and to safeguard accidental forest-fire areas as set-asides;(3)renewing the current prescribed-burning criterion of the Finnish PEFC forest-certification standard with more ambitious ecological goals;and(4)re-introducing prescribed burnings in commercial state forests where management targets are under political steering. 展开更多
关键词 BIODIVERSITY Conservation areas Fire-dependent species Forest certification Red-listed species Restoration burnings
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