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Population Viability Analysis of Gloydius shedaoensis from Northeastern China:A Contribution to the Assessment of the Conservation and Management Status of an Endangered Species 被引量:2
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作者 LIU Peng SUN Lixin +3 位作者 LI Jianli WANG Li ZHAO Wenge JIA Jingbo 《Asian Herpetological Research》 SCIE 2010年第1期48-56,共9页
Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangere... Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangered species by providing a way for conservation and management. Research based on the ecological simulation tools can evaluate alternative mitigation strategies in terms of their benefits to the populations, which are vital for informed decision-making. In this paper, using the program VORTEX 9.42, we developed a population viability analysis(PVA) for the Shedao pit-viper to:(1) address the extinction likelihood of the population;(2) simulate population dynamics under various environment events, and(3) evaluate the efficacy of current protection and management strategies. Overall, we found the population to be susceptible to the factors of catastrophic events, mortality and environment capacity. The population is recovering slowly at present on account of improvement of habitat and greater food availability. Under the current conditions, the probability of extinction in 100 years is approximately zero. These data coincide with the evidence that the wild population may be arriving at K. Our results strengthen the view that protection and management can create a pronounced effect on populations of this endangered species. 展开更多
关键词 Gloydius shedaoensis VORTEX simulation model sensitivity analysis model veracity test species conservation
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Tree species diversity and stand structure along major community types in lowland primary and secondary moist deciduous forests in Tripura,Northeast India 被引量:4
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作者 Koushik Majumdar Uma Shankar Badal Kumar Datta 《Journal of Forestry Research》 CAS CSCD 2012年第4期553-568,共16页
Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging ... Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH (diameter at breast height) using 28 permanent belt transects with a size of 1 ha (10 m × 1000 m). Four different tree communities were identified. The primary forests was dominated by Shorea robusta (mean density 464.77 trees.ha^-1, 105 species) and Schima wallichii (336.25 trees.ha^-1, 82 species), while the secondary forests was dominated by Tectona grandis (333.88 trees.ha^-1, 105 species) and Hevea brasiliensis (299.67 trees.ha^-1, 82 species). Overall mean basal area in this study was 18.01m2.ha^-1; the maximum value was recorded in primary Shorea forest (26.21 m2.ha^-1). Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumu- lation of native oligarchic small tree species. Seventeen species were recorded with 〈2 individuals of which Saraca asoka (Roxb.) de Wilde and Entada phaseoloides (L.) Men'. etc. extensively used in local ethnomedicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer (105 species) than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary T. grandis L. dominated community. 展开更多
关键词 diversity and stand structure moist deciduous forest species conservation tree community types
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Climate Change Adaptation Planning for Biodiversity Conservation:A Review
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作者 James E. M. WATSON Madhu RAO +1 位作者 KANG Ai-Li XIE Yan 《Advances in Climate Change Research》 SCIE 2012年第1期1-11,共11页
Climate change has been linked to well-documented changes in physiology, phenology, species distributions, and in some cases, extinction. Projections of future change point to dramatic shifts in the states of many eco... Climate change has been linked to well-documented changes in physiology, phenology, species distributions, and in some cases, extinction. Projections of future change point to dramatic shifts in the states of many ecosystems. Aceommodating these shifts to effectively conserve biodiversity in the context of uncertain climate regimes represents one of the most difficult challenges faced by conservation planners. A number of adaptation strategies have been proposed for managing species and ecosystems in a changing climate. However, there has been little guidance available on integrating climate change adaptation strategies into contemporary conservation planning frameworks. The paper reviews the different approaches being used to integrate climate change adaptation into conservation planning, broadly categorizing strategies as continuing and extending on "best practice" principles and those that integrate species vulnerability assessments into conservation planning. We describe the characteristics of a good adaptation strategy emphasizing the importance of incorporating clear principles of flexibility and efficiency, accounting for uncertainty, integrating human response to climate change and understanding trade-offs. 展开更多
关键词 climate change adaptation conservation planning species conservation vulnerabilitv analvsis
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The Lynx and Hare Data of 200 Years as the Nonlinear Conserving Interaction Based on Noether’s Conservation Laws and Stability
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2021年第11期2807-2847,共41页
We applied <em>n</em>-variable conserving nonlinear differential equations (<em>n</em>-CNDEs) to the population data of the 10-year cycles of Canadian lynx (1821-2016) and the snowshoe hare (18... We applied <em>n</em>-variable conserving nonlinear differential equations (<em>n</em>-CNDEs) to the population data of the 10-year cycles of Canadian lynx (1821-2016) and the snowshoe hare (1845-1921). Modeling external effects as perturbations to population dynamics, recovering and restorations from disintegrations (or extinctions), stability and survival strategies are discussed in terms of the conservation law inherent to dynamical interactions among species. The 2-variable conserving nonlinear interaction (2CNIs) is extended to 3, 4, ... <em>n</em>-variable conserving nonlinear interactions (<em>n</em>-CNIs) of species by adjusting minimum unknown parameters. The population cycle of species is a manifestation of conservation laws existing in complicated ecosystems, which is suggested from the CNDE analysis as <em>a standard rhythm</em> of interactions. The ecosystem is a consequence of the long history of nonlinear interactions and evolutions among life-beings and the natural environment, and the population dynamics of an ecosystem are observed as approximate CNIs. Physical analyses of the conserving quantity in nonlinear interactions would help us understand why and how they have developed. The standard rhythm found in nonlinear interactions should be considered as a manifestation of the survival strategy and the survival of the fittest to the balance of biological systems. The CNDEs and nonlinear differential equations with time-dependent coefficients would help find useful physical information on the survival of the fittest and symbiosis in an ecosystem. 展开更多
关键词 The 10-Year Population Cycles of Canadian Lynx and Snowshoe Hare The Standard Rhythm of Interactions Noether’s conservation Law Conserving Nonlinear Interactions of species
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Effect of Growth Regulators on Rooting of Hardwood Cuttings of Lycium shawii, Nitraria retusa and Farsetia aegyptia 被引量:2
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作者 M. K. Suleiman N. R. Bhat S. Jacob R. R. Thomas 《Journal of Agricultural Science and Technology(B)》 2011年第3期414-419,共6页
Utilization of native plants in urban landscaping can potentially support their conservation and safeguard endangered native species from extinction. In this study, efforts were made to standardize vegetative propagat... Utilization of native plants in urban landscaping can potentially support their conservation and safeguard endangered native species from extinction. In this study, efforts were made to standardize vegetative propagation techniques for Lycium shawiL Nitraria retusa and Farsetia aegyptia. Effects of varying concentrations of rooting hormones on the success of rooting of hardwood cuttings of these species were studied in this research. Rooting in hardwood cuttings of Lycium shawii was enhanced (100%) by treating them with 1,000 ppm IBA, Ormone radicante in polvere (5,000 ppm NAA) and hormex (1,000 ppm IBA). Treatment with 1,000 ppm NAA was found to be effective for Nitraria retusa, while marginal success was recorded in rooting of hardwood cuttings of Farsetia aegyptia when treated with 400 ppm NAA. Rooting in untreated cuttings was 80%. 展开更多
关键词 Urban landscape vegetative propagation species conservation growth hormones NAA IBA and GA3.
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Lesser Kestrel Foraging Habitats in Special Protection Areas in Agro-ecosystems
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作者 Antonia Galanaki Theodoros Kominos Martin John Jones 《Journal of Agricultural Science and Technology(A)》 2017年第7期479-492,共14页
The European Union (EU) Wild Birds Directive recognises that the most serious threats to wild birds' conservation in Europe are habitat loss and degradation, and hence, habitats of threatened and migratory species ... The European Union (EU) Wild Birds Directive recognises that the most serious threats to wild birds' conservation in Europe are habitat loss and degradation, and hence, habitats of threatened and migratory species must be protected with the establishment of the network of the special protection areas (SPAs) for migratory and endangered bird species in the EU member states. The major European population of the lesser kestrel Falco naumanni, a migratory falcon listed in Annex I of the Birds Directive, occurs in low-input farming systems in the Mediterranean basin, including Greece. The aim of this study was to identify foraging habitats of lesser kestrels and relate them to the delimited SPAs in the agro-ecosystems of Greece, where the stronghold of the species population for Greece occurs. Foraging habitat preferences were assessed using Poisson regression models (PRMs). SPAs were examined on whether they can effectively protect foraging habitats for breeding lesser kestrels in the study area. Foraging lesser kestrel abundance was positively associated with grasslands and non-irrigated land (dry cereals), and negatively associated with irrigated land (wet cotton), scrubland and woodland. Electricity facilities were used as foraging perches by lesser kestrels. The current SPAs cover a small percentage of the species' foraging sites and cannot be considered coherent enough to support and protect the foraging habitats of lesser kestrels and other priority species in the agro-ecosystems of the study area. Proposals for effective conservation of low-input farming systems, supporting priority species, are also presented. 展开更多
关键词 Falco naumanni special protection areas (SPAs) Poisson regression models (PRMs) foraging habitats species conservation AGRO-ECOSYSTEMS Greece.
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Functional diversity of Cercidiphyllum japonicum, communities in the Shennongjia Reserve, central China 被引量:8
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作者 Jintun Zhang Bin Zhang Zhiying Qian 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期171-177,共7页
Functional diversity is significant to ecological processes of plant communities. We analyzed the variation of functional diversity of endangered species, Cercidiphyllum japonicum, communities along an elevational gra... Functional diversity is significant to ecological processes of plant communities. We analyzed the variation of functional diversity of endangered species, Cercidiphyllum japonicum, communities along an elevational gradient in the Shennongjia Reserve, central China. Sixty plots of 10 9 20 m from 1,350 to 2,050 m were set up and species composition, traits and environmental variables were measured and recorded. These data were analyzed using five functional diversity indices, functional attribute diversity, modified functional attribute diversity, plot based functional diversity, community based functional diversity and Rao's functional diversity indices(Rao's index),Functional diversities of C. japonicum communities were rich and varied greatly. Functional diversity declined nonlinearly with increasing elevation. Functional diversity was significantly correlated with species richness and heterogeneity. Elevation was a key environmental variable influencing functional diversity and species diversity. The five functional diversity indices were all effective for measuring functional diversity of communities. Functional diversity can be used as an indicator of conservation efficiency of endangered species such as C. japonicum. 展开更多
关键词 Endangered species Functional trait Functional diversity Environmental gradient conservation
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Quantifying landscape linkages among giant panda subpopulations in regional scale conservation 被引量:3
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作者 Dunwu QI Yibo HU +3 位作者 Xiaodong GU Xuyi YANG Guang YANG Fuwen WEI 《Integrative Zoology》 SCIE CSCD 2012年第2期165-174,共10页
Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolat­ed populations of endangered species.Currently,some of the giant panda populations are isolated,which... Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolat­ed populations of endangered species.Currently,some of the giant panda populations are isolated,which threat­ens their long-term survival,particularly in the Xiaoxiangling mountains.In the present study,we quantified niche requirements and then identified potential linkages of giant panda subpopulations in the most isolated re­gion,using ecological niche factor analysis and a least-cost path model.Giant pandas preferred habitat with co­nifer forest and gentle slopes(>20 to≤30°).Based on spatial distribution of suitable habitat,linkages were iden­tified for the Yele subpopulation to 4 other subpopulations(Liziping,Matou,Xinmin and Wanba).Their lengths ranged from 15 to 54 km.The accumulated cost ranged from 693 to 3166 and conifer forest covered over 31%.However,a variety of features(e.g.major roads,human settlements and large unforested areas)might act as barriers along the linkages for giant panda dispersal.Our analysis quantified giant panda subpopulation connec­tivity to ensure long-term survival. 展开更多
关键词 Ailuropoda melanoleuca ecological niche factor analysis giant panda landscape connectivity least-cost path analysis species conservation
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Protecting endemic seed plants on the Tibetan Plateau under future climate change: migration matters 被引量:4
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作者 Yujing Yan Zhiyao Tang 《Journal of Plant Ecology》 SCIE CSCD 2019年第6期962-971,共10页
Aims Climate change in the near future may become a major threat to high-altitude endemics by greatly altering their distribution.Our aims are to(i)assess the potential impacts of future climate change on the diversit... Aims Climate change in the near future may become a major threat to high-altitude endemics by greatly altering their distribution.Our aims are to(i)assess the potential impacts of future climate change on the diversity and distribution of seed plants endemic to the Tibetan Plateau and(ii)evaluate the conservation effectiveness of the current National Nature Reserves(NNRs)in protecting the endemic plants in the face of climate change.Methods We projected range shifts of 993 endemic species to the years 2050 and 2070 under two representative concentration pathway scenarios using an ensemble species distribution modeling framework and evaluated range loss,species-richness change and coverage of the current conservation network considering two dispersal scenarios.Important Findings In a full-dispersal scenario,72–81%of the species would expand their distribution by 2070,but 6–20%of the species would experience>30%range loss.Most species would shift to the west.The projected species net richness would increase across the region on average.In a no-dispersal scenario,15–59%of the species would lose>30%of their current habitat by 2070.Severe species loss may occur in the southeastern and the eastern peripheral plateau.Seventeen percent of species ranges are covered by the NNRs on average and may increase in the future if species disperse freely.We found a significant difference of species redistribution patterns between different dispersal scenarios and highlighted the importance of migration in this region. 展开更多
关键词 BIODIVERSITY global change impact assessment nature reserves species conservation species distribution models
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