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Oil Pollution and Bio-Diversity Conservation in Nigeria: An Assessment of Legal Framework
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作者 Adesina Temitayo Bello Joseph Amadi 《Journal of Geoscience and Environment Protection》 2019年第8期354-371,共18页
Oil pollution distorts aquatic life which not only destroys the source of livelihood of fishers, but also causes a shortage of supply of seafood. It destroys the fertile soil, which makes it difficult for the farmer t... Oil pollution distorts aquatic life which not only destroys the source of livelihood of fishers, but also causes a shortage of supply of seafood. It destroys the fertile soil, which makes it difficult for the farmer to farm as a means of livelihood, and the supply of agricultural produce is reduced as a result of poor crop yields. This article deals with the effects of oil pollution on biological diversity in Nigeria. It espouses the legal regime of oil pollution and biological diversity. The article highlights threatened components of the country’s biological diversity and the measures taken by the government to control and checks the activities of oil companies in a bid to ensure that they abide by best practices for the conservation of the country’s biological diversity. This article recommended that there needs to be a collective effort of the government, Petroleum Companies and host communities to ensure that Nigeria’s Bio-diversities is conserved. The article established that Bio-diversity is the true essence of natural life;however, oil pollution can cause the total destruction of this natural life, hence, the need for the conservation of our bio-diversity, for the protection of the environment and human existence. 展开更多
关键词 Oil POLLUTION BIOLOGICAL DIVERSITY conservation
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Conservation genomic investigation of an endangered conifer,Thuja sutchuenensis,reveals low genetic diversity but also low genetic load 被引量:1
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作者 Tongzhou Tao Richard IMilne +4 位作者 Jialiang Li Heng Yang Shiyang Wang Sihan Chen Kangshan Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第1期78-90,共13页
Endangered species generally have small populations with low genetic diversity and a high genetic load.Thuja sutchuenensis is an endangered conifer endemic to southwestern China.It was once considered extinct in the w... Endangered species generally have small populations with low genetic diversity and a high genetic load.Thuja sutchuenensis is an endangered conifer endemic to southwestern China.It was once considered extinct in the wild,but in 1999 was rediscovered.However,little is known about its genetic load.We collected 67 individuals from five wild,isolated T.sutchuenensis populations,and used 636,151 SNPs to analyze the level of genetic diversity and genetic load in T.sutchuenensis to delineate the conservation units of T.sutchuenensis,based on whole transcriptome sequencing data,as well as target capture sequencing data.We found that populations of T.sutchuenensis could be divided into three groups.These groups had low levels genetic diversity and were moderately genetically differentiated.Our findings also indicate that T.sutchuenensis suffered two severe bottlenecks around the Last Glaciation Period and Last Glacial Maximum.Among Thuja species,T.sutchuenensis presented the lowest genetic load and hence might have purged deleterious mutations efficiently through purifying selection.However,distribution of fitness effects analysis indicated a high extinction risk for T.sutchuenensis.Multiple lines of evidence identified three management units for T.sutchuenensis.Although T.sutchuenensis possesses a low genetic load,low genetic diversity,suboptimal fitness,and anthropogenic pressures all present an extinction risk for this rare conifer.This might also hold true for many endangered plant species in the mountains all over the world. 展开更多
关键词 Sichuan Arborvitae Genetic load Deleterious mutations Demographic history conservation genomics
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Bird species composition and conservation challenges in the Gaoligong Mountains, one of the most diverse bird areas in the world 被引量:2
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作者 Fei Wu Jian-Yun Gao +13 位作者 Dao Yan Le Yang Lu-Ming Liu Shun-Yu Yao Chang-Sheng Zuo Jun Sun Ge Gao Jian-Yong Su Li Luo Ying-Chun Li Ming Liu Yuan-Fang Hu Ming Wei Xiao-Jun Yang 《Zoological Research(Diversity and Conservation)》 2024年第1期20-50,共31页
The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird su... The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird surveys conducted in the GLGM between 2010 and 2022.We found that the GLGM harbors tremendous bird diversity,with a total of 796 documented bird species in the region.Nearly a quarter(23.0%)of these species are listed as state key protected species or as Chinese and global threatened species.Analysis of species richness at the county level showed a decreasing trend with increasing latitude,with the greatest diversity in Yingjiang(661 species).Observations indicated that the GLGM belongs to the Oriental realm,primarily composed of bird species from southern and southwestern China.The GLGM plays an important role in avian conservation by sheltering exceptional bird diversity,providing corridors and flyways for bird migration and dispersal,and mitigating the effects of climate change.In response to the conservation needs of birds and other wildlife,the Chinese government has established numerous protected areas within the GLGM.Despite these efforts,avian conservation still faces considerable challenges in the GLGM due to limitations in the protected area network,transboundary nature of the regions,and existing gaps in monitoring and research. 展开更多
关键词 BIRDS Gaoligong Mountains Zoogeographic region conservation challenge
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Mammals of Gaoligong Mountain in China:Diversity,distribution,and conservation 被引量:2
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作者 Quan Li Xue-You Li +13 位作者 Wen-Qiang Hu Wen-Yu Song Shui-Wang He Hong-Jiao Wang Zhe-Chang Hu Meng-Cheng Li Kenneth Otieno Onditi Zhong-Zheng Chen Chang-Zhe Pu Yun Xiong Cai-Hong Rao Fu-You Zhang Chang-Sheng Zuo Xue-Long Jiang 《Zoological Research(Diversity and Conservation)》 2024年第1期3-19,共17页
Gaoligong Mountain(hereafter,GLGM)is located at the intersection of Myanmar and China’s Yunnan Province and Xizang Zizhiqu,and spans three globally significant biodiversity hotspots:the Himalayas,Indo-Burma,and the M... Gaoligong Mountain(hereafter,GLGM)is located at the intersection of Myanmar and China’s Yunnan Province and Xizang Zizhiqu,and spans three globally significant biodiversity hotspots:the Himalayas,Indo-Burma,and the Mountains of Southwest China.Although surveys of mammals in this ecologically important region have a long history,there is no comprehensive systematic checklist and distribution account of the mammals of GLGM.Here,we compiled a mammal species checklist of GLGM based on thorough field investigations and literature reviews.We also examined specimen collections and applied camera trapping surveys to explore the region’s mammal diversity and distribution patterns.We recorded 212 mammal species in nine orders,33 families,and 119 genera,which accounts for 30.5%of China’s mammal species,and a high proportion of nationally protected(50)and globally threatened(29)species.Mammal species richness showed a symmetrical unimodal curve along the elevation gradient,peaking at intermediate elevations(2000 to 2500 m above sea level(asl)),and increasing generally from south to north,slightly higher in the east slope than in the west.Cluster analysis and non-metric multidimensional scaling revealed three distinct elevational assemblages(<900 m asl.,900-3500 m asl.,and>3500 m asl)and significant south-to-north variation,but no substantial differences between the east and west slopes.The GLGM present a unique conservation value due to the high proportions of rare and endangered mammal species,complex faunal composition,high endemism,and being the distribution boundary for many species.This study is an important phased account of mammal diversity in GLGM and makes a prospect for future research. 展开更多
关键词 Biodiversity hotspot Eastern Himalaya Gaoligong Mountain ENDEMISM Mammal conservation Hengduan Mountains
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Achievements and challenges of primate conservation in China 被引量:1
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作者 Bao-Guo Li He Zhang +21 位作者 Ming Li Xue-Long Jiang Peng-Fei Fan Jiang Zhou Song-Tao Guo Xiao-Guang Qi Jin-Hua Li Ji-Qi Lu Dong-Po Xia Liang-Wei Cui Zuo-Fu Xiang Qi-Hai Zhou Zhi-Pang Huang Cheng-Ming Huang Wen Xiao Hui-Jian Hu Zhi-Xin Zhou Ming-Yong Chen Da-Yong Li Peng-Lai Fan Yin Yang Ru-Liang Pan 《Zoological Research(Diversity and Conservation)》 2024年第1期66-74,共9页
The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe e... The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern society.In response,China has implemented various ecological conservation measures,including habitat restoration and protection.These efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate populations.In the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in China.Despite improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small populations.Species such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(N.hainanus)remain particularly vulnerable due to their limited distribution ranges and extremely small populations.Insufficient scientific data,fragmented information,and not enough studies in conservation biology further compound the challenges.Moreover,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(N.pygmaeus),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(T.shortridgei),and capped langur(T.pileatus),which hinders the development of practical and targeted conservation management strategies.Therefore,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conservation strategies and regional cooperation.There is also a need to establish a comprehensive and systematic research database platform,conduct continuous and in-depth research in primate biology,and actively engage in the scientific assessment of ecotourism.Additionally,strengthening public awareness and education on wildlife conservation remains essential.Such integrated and systematic efforts will provide scientific support for the current and future conservation and management of primate species in China. 展开更多
关键词 PRIMATES BIODIVERSITY Habitat fragmentation Habitat restoration conservation strategies
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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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Assessing the conservation impact of Chinese indigenous chicken populations between ex-situ and in-situ using genome-wide SNPs
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作者 Wenting Li Chaoqun Gao +7 位作者 Zhao Cai Sensen Yan Yanru Lei Mengya Wei Guirong Sun Yadong Tian Kejun Wang Xiangtao Kang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期975-987,共13页
Conservation programs require rigorous evaluation to ensure the preservation of genetic diversity and viability of conservation populations. In this study, we conducted a comparative analysis of two indigenous Chinese... Conservation programs require rigorous evaluation to ensure the preservation of genetic diversity and viability of conservation populations. In this study, we conducted a comparative analysis of two indigenous Chinese chicken breeds, Gushi and Xichuan black-bone, using whole-genome SNPs to understand their genetic diversity, track changes over time and population structure. The breeds were divided into five conservation populations(GS1, 2010, ex-situ;GS2, 2019, ex-situ;GS3, 2019, in-situ;XB1, 2010, in-situ;and XB2, 2019, in-situ) based on conservation methods and generations. The genetic diversity indices of three conservation populations of Gushi chicken showed consistent trends, with the GS3 population under in-situ strategy having the highest diversity and GS2 under ex-situ strategy having the lowest. The degree of inbreeding of GS2 was higher than that of GS1 and GS3. Conserved populations of Xichuan black-bone chicken showed no obvious changes in genetic diversity between XB1 and XB2. In terms of population structure, the GS3 population were stratified relative to GS1 and GS2. According to the conservation priority, GS3 had the highest contribution to the total gene and allelic diversity in GS breed, whereas the contribution of XB1 and XB2 were similar. We also observed that the genetic diversity of GS2 was lower than GS3, which were from the same generation but under different conservation programs(in-situ and ex-situ). While XB1 and XB2 had similar levels of genetic diversity. Overall, our findings suggested that the conservation programs performed in ex-situ could slow down the occurrence of inbreeding events, but could not entirely prevent the loss of genetic diversity when the conserved population size was small, while in-situ conservation populations with large population size could maintain a relative high level of genetic diversity. 展开更多
关键词 genome-wide SNPs conservation genetic diversity ex-situ IN-SITU
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Importance of Plant Biodiversity and Long-Term Conservation of Plant Genetic Resources via Biotechnological Strategies
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作者 Ergun Kaya 《Journal of Biosciences and Medicines》 2024年第11期584-591,共8页
Although climate changes are predicted to be an increasingly dominant threat to plant biodiversity, the degradation of ecosystems witnessed to date has been largely driven by factors such as human-induced habitat loss... Although climate changes are predicted to be an increasingly dominant threat to plant biodiversity, the degradation of ecosystems witnessed to date has been largely driven by factors such as human-induced habitat loss and fragmentation, overexploitation, pollution and the introduction of invasive species. Given the evidence that climate changes and anthropogenic pressures have greatly increased the extinction of natural populations of species, we can recognize that human-induced land use and climate changes are perhaps the greatest threats to terrestrial biodiversity. In this context, effective prioritization of conservation efforts is critical for the sustainability of biodiversity, as current environmental changes are likely to continue in the future. Countries with limited financial resources for conservation projects may be at greater risk from habitat loss, direct harvesting and invasive species, and may also lead to unsustainable exploitation of resources, further accelerating species loss through direct harvesting and causing rapid loss of biodiversity. In this context, the protection of biodiversity is an important issue that concerns the entire world population. Causes such as anthropogenic pressures, great fires, introduction of new species from different regions, invasion of cultivars and dominant species cause a dramatic impact on plant biodiversity as well as an increase in the number of threatened species. Plant biodiversity constitutes the natural source of products used in the food and pharmaceutical industries and also provides basic different raw materials. On the other hand, plant biodiversity is important in the development of species and more productive species that are more resistant to biological and environmental stresses, and in providing new genetic information for feeding programs. Advances in plant biotechnology, particularly in vitro cultures and molecular biology, have been a powerful tool in the control and conservation of plant biodiversity. Today, biotechnological methods include the most suitable methods for the pathogen-free short-, medium- and long-term preservation of ornamental plants, medicinal and aromatic plants and woody species that are in danger of extinction. In vitro conservation strategies are especially important in the protection of plant species that are vegetatively propagated and have seeds that are intolerant to desiccation. In addition, in vitro techniques provide a reliable platform for the international exchange of plant material, enable the creation of large collections using minimal space, enable the acquisition of valuable materials for wild species recovery, and facilitate molecular research and ecological studies. 展开更多
关键词 BIODIVERSITY BIOTECHNOLOGY CRYOPRESERVATION In Vitro conservation
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Nonuniform Dependence on the Initial Data for Solutions of Conservation Laws
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作者 John M.Holmes Barbara Lee Keyfitz 《Communications on Applied Mathematics and Computation》 EI 2024年第1期489-500,共12页
In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results a... In this paper,we study systems of conservation laws in one space dimension.We prove that for classical solutions in Sobolev spaces H^(s),with s>3/2,the data-to-solution map is not uniformly continuous.Our results apply to all nonlinear scalar conservation laws and to nonlinear hyperbolic systems of two equations. 展开更多
关键词 conservation laws Data-to-solution map Nonuniform dependence
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A LOW-REGULARITY FOURIER INTEGRATOR FOR THE DAVEY-STEWARTSON II SYSTEM WITH ALMOST MASS CONSERVATION
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作者 Cui NING Chenxi HAO Yaohong WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1536-1549,共14页
In this work,we propose a low-regularity Fourier integrator with almost mass conservation to solve the Davey-StewartsonⅡsystem(hyperbolic-elliptic case).Arbitrary order mass convergence could be achieved by the suita... In this work,we propose a low-regularity Fourier integrator with almost mass conservation to solve the Davey-StewartsonⅡsystem(hyperbolic-elliptic case).Arbitrary order mass convergence could be achieved by the suitable addition of correction terms,while keeping the first order accuracy in H~γ×H^(γ+1)for initial data in H^(γ+1)×H^(γ+1)withγ>1.The main theorem is that,up to some fixed time T,there exist constantsτ_(0)and C depending only on T and‖u‖_(L^(∞)((0,T);H^(γ+1)))such that,for any 0<τ≤τ_(0),we have that‖u(t_(n),·)-u^(n)‖H_γ≤C_(τ),‖v(t_(n),·)-v^(n)‖_(Hγ+1)≤C_(τ),where u^(n)and v^(n)denote the numerical solutions at t_(n)=nτ.Moreover,the mass of the numerical solution M(u^(n))satisfies that|M(u^(n))-M(u_0)|≤Cτ~5. 展开更多
关键词 Davey-StewartsonⅡsystem low-regularity exponential integrator first order accuracy mass conservation
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Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws
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作者 Feng Zheng Jianxian Qiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期605-624,共20页
In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy ... In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation laws.It can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary conditions.Furthermore,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO method.Extensive numerical tests are performed to verify the high resolution and high accuracy of the scheme. 展开更多
关键词 Finite volume Dimension by dimension HWENO Hyperbolic conservation laws
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The Current Conservation Efforts and Future Prospects for the Endangered Nubian Ibex (Capra nubiana ibex) in Sudan
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作者 Lubna Mohammed Abdallah Hassan Mutasim Essa Abdallah Adam +1 位作者 Latifa Altigani Adam Abakar Nasir Yousif Gaboush Brema 《Journal of Environmental Protection》 2024年第1期39-62,共24页
A comprehensive action plan for the conservation of the endangered species, the Nubian ibex in Sudan, can be developed by gaining a thorough understanding of their current status, conservation strategy, and relevant l... A comprehensive action plan for the conservation of the endangered species, the Nubian ibex in Sudan, can be developed by gaining a thorough understanding of their current status, conservation strategy, and relevant laws and regulations, as well as raising awareness about the importance of protecting endangered species. The Nubian ibex is listed as an endangered species on The International Union for Conservation of Nature (IUCN) Red List, highlighting the need for further research on population conservation efforts due to insufficient population data. To address this knowledge gap, a questionnaire was conducted with various stakeholders, including police officers, researchers, and lecturers, representing a diverse range of organizations and universities. The findings revealed that hunting is the primary factor contributing to endangerment. Mammals account for 80% of endangered species, while reptiles comprise less than one-tenth. Research centers are recognized as the main governing body, and 85% of participants are concerned about the declining population. Hunting accounted for less than half of the threats to the ibex population in Sudan, while habitat loss made up a quarter. Mining, climate change, human activity, and agriculture were also identified as risks. However, there were no plans, strategies, procedures, or measures in place to conserve the Nubian ibex. There were also no initiatives to preserve its biodiversity, and awareness about endangered species was lacking. Although participants believed that laws were effective in protecting the ibex, no licenses were issued for its conservation, and annual surveys were not conducted. Additionally, there were no recorded instances of Mukhalfat related to the Nubian ibex. In light of these findings, we propose various conservation measures to address these challenges. These measures include the implementation of laws and regulations, conducting annual surveys to monitor population trends, protecting habitats, establishing breeding and releasing programs, launching awareness campaigns, undertaking rehabilitation efforts, enhancing research efforts, and developing comprehensive conservation strategies. Additionally, it is crucial to foster cooperation among wildlife institutes to ensure the effective implementation of these conservation measures. 展开更多
关键词 Nubian Ibex SUDAN Endangered Species conservation Status Law REGULATIONS AWARENESS
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Ecosystem services potential and soil conservation policies with emphasis on degraded pastures in Brazil
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作者 Adriana Monteiro da Costa Maise Soares de Moura +5 位作者 Isadora Fonseca Navarro Victor Cordeiro da Silva Teresa Cristina TarléPissarra Carlos Alberto Valera Luís Filipe Sanches Fernandes Fernando Antonio Leal Pacheco 《Geography and Sustainability》 CSCD 2024年第4期660-672,共13页
Different global agendas have discussed the role of soils in mitigating and reducing global problems related to climate change,food security,biodiversity and erosion,among others.With this in mind,the aim was to draw ... Different global agendas have discussed the role of soils in mitigating and reducing global problems related to climate change,food security,biodiversity and erosion,among others.With this in mind,the aim was to draw up an overview of the main soil agendas in Europe and Brazil,analysing their impact on the establishment of legal frameworks for soil use and conservation.In Brazil,pastures are seen as an important alternative for converting degraded areas into ecosystem services.To this end,a literature review was carried out using databases on the Scopus,Web of Science,Science Direct and Scielo platforms,as well as consulting documents from the European Union Missions in Horizon Europe and Brazilian legislation on the subject.In a pilot river basin,the Potential for Conservation Use(PCU)method was applied,which is used in Brazil to assess the impacts of different uses on the natural capital of soils,serving as a metric to guide public soil conservation policies.It was concluded that,on the European scene,discussions on soils have taken place in an integrated and organised way,with actions to mobilise different players in society.In Brazil,even though there are important legal frameworks,actions are still restricted and disjointed,pointing to the need for progress in soil governance.In both scenarios,there is a need for scientifically validated metrics at regional scales that can contribute to a harmonised database capable of subsidising the development of efficient public policies to advance soil conservation at a global level. 展开更多
关键词 EU mission Soil governance conservation use potential Soil services PronaSolos
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ENERGY CONSERVATION FOR THE WEAK SOLUTIONS TO THE 3D COMPRESSIBLE NEMATIC LIQUID CRYSTAL FLOW
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作者 谭忠 李心亮 杨惠 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期851-864,共14页
In this paper,we establish some regularity conditions on the density and velocity fields to guarantee the energy conservation of the weak solutions for the three-dimensional compressible nematic liquid crystal flow in... In this paper,we establish some regularity conditions on the density and velocity fields to guarantee the energy conservation of the weak solutions for the three-dimensional compressible nematic liquid crystal flow in the periodic domain. 展开更多
关键词 compressible nematic liquid crystal flow weak solutions energy conservation
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REFINED CONSERVATION LAW FOR AN EVEN ORDER ELLIPTIC SYSTEM WITH ANTISYMMETRIC POTENTIAL
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作者 Changyu GUO Changlin XIANG Gaofeng ZHENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2111-2124,共14页
Conservation law plays a very important role in many geometric variational problems and related elliptic systems.In this note,we refine the conservation law obtained by Lamm-Rivière for fourth order systems and d... Conservation law plays a very important role in many geometric variational problems and related elliptic systems.In this note,we refine the conservation law obtained by Lamm-Rivière for fourth order systems and de Longueville-Gastel for general even order systems. 展开更多
关键词 conservation law Uhlenbeck's gauge transform even order elliptic system antisymmetric potential weak compactness
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Conservation genomics provides insights into genetic resilience and adaptation of the endangered Chinese hazelnut, Corylus chinensis
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作者 Zhen Yang Lisong Liang +3 位作者 Weibo Xiang Lujun Wang Qinghua Ma Zhaoshan Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第3期294-308,共15页
Global climate change has increased concerns regarding biodiversity loss.However,many key conservation issues still required further research,including demographic history,deleterious mutation load,adaptive evolution,... Global climate change has increased concerns regarding biodiversity loss.However,many key conservation issues still required further research,including demographic history,deleterious mutation load,adaptive evolution,and putative introgression.Here we generated the first chromosome-level genome of the endangered Chinese hazelnut,Corylus chinensis,and compared the genomic signatures with its sympatric widespread C.kwechowensis-C yunnanensis complex.We found large genome rearrangements across all Corylus species and identified species-specific expanded gene families that may be involved in adaptation.Population genomics revealed that both C.chinensis and the C.kwechowensis-C.yunnanensis complex had diverged into two genetic lineages,forming a consistent pattern of southwestern-northern differentiation.Population size of the narrow southwestern lineages of both species have decreased continuously since the late Miocene,whereas the widespread northern lineages have remained stable(C.chinensis) or have even recovered from population bottlenecks(C.kwechowensis-C.yunnanensis complex) during the Quaternary.Compared with C.kwechowensis-C. yunnanensis complex,C.chinensis showed significantly lower genomic diversity and higher inbreeding level.However,C.chinensis carried significantly fewer deleterious mutations than C.kwechowensis-C. yunnanensis complex,as more effective purging selection reduced the accumulation of homozygous variants.We also detected signals of positive selection and adaptive introgression in different lineages,which facilitated the accumulation of favorable variants and formation of local adaptation.Hence,both types of selection and exogenous introgression could have mitigated inbreeding and facilitated survival and persistence of C.chinensis.Overall,our study provides critical insights into lineage differentiation,local adaptation,and the potential for future recovery of endangered trees. 展开更多
关键词 conservation genomics Demographic history INBREEDING Genetic load Runs of homozygosity Local adaptation
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Fertilization and Soil Ploughing Practices under Changing Physical Environment Lead to Soil Organic Carbon Dynamics under Conservation Agriculture in Rice-Wheat Cropping System: A Scoping Review
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作者 Salwinder Singh Dhaliwal Arvind Kumar Shukla +8 位作者 Sanjib Kumar Behera Sarwan Kumar Dubey Agniva Mandal Mehakpreet Kaur Randhawa Sharanjit Kaur Brar Gagandeep Kaur Amardeep Singh Toor Sohan Singh Walia Priyadarshani Arun Khambalkar 《Agricultural Sciences》 2024年第1期82-113,共32页
Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the ... Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the loss of soil-organic-carbon (SOC), which further enhances soil fertility. Different fractions of SOC pools react to the alterations in management practices and indicate changes in SOC dynamics as compared to total C in the soil. Higher SOC levels in soil have been observed in case of reduced/no-till (NT) practices than conventional tillage (CT). However, between CT and zero tillage/NT, total SOC stocks diminished with an increase in soil depth, which demonstrated that the benefits of SOC are more pronounced in the topsoil under NT. Soil aggregation provides physical protection to C associated with different-sized particles, thus, the improvement in soil aggregation through CA is an effective way to mitigate soil C loss. Along with less soil disturbance, residual management, suitable crop rotation, rational application of manures and fertilizers, and integrated nutrient management have been found to be effective in not only improving soil C stock but also enhancing the soil health and productivity. Thus, CA can be considered as a potential method in the build-up of SOC of soil in rice-wheat system. 展开更多
关键词 TILLAGE conservation Agriculture Soil Organic Carbon Carbon Fractions Rice-Wheat System Organic Amendments
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Latitudinal gradients of biodiversity and ecosystem services in protected and non-protected oak forest areas can inform climate smart conservation
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作者 Anders Forsman Johanna Sunde +1 位作者 Romana Salis Markus Franzen 《Geography and Sustainability》 CSCD 2024年第4期647-659,共13页
Adaptive governance of areas set aside for future protection of biodiversity,sustainable production,and recreation requires knowledge about whether and how effects of area protection are modulated by climate change an... Adaptive governance of areas set aside for future protection of biodiversity,sustainable production,and recreation requires knowledge about whether and how effects of area protection are modulated by climate change and redistribution of species.To investigate this,we compare biodiversity of plants(assessed using vegetation plots)and arthropods(collected with Malaise traps,analyzed using metabarcoding)and productivity(tree growth,determined using dendrochronology)in protected and non-protected oak(Quercus spp.)forests along a latitudinal gradient(55.6°N–60.8°N)in Sweden.We also compare historical,recent and projected future climate in the region.In contrast to established global latitudinal diversity gradients,species richness of plants and arthropods increased northwards,possibly reflecting recent climate-induced community redistributions,but neither was higher in protected than in non-protected areas,nor associated with contemporary ground temperature.Species composition of arthropods also did not differ between protected and non-protected areas.Arthropod biomass increased with latitude,suggesting that the magnitude of cascading effects mediated via their roles as pollinators,herbivores,and prey for other trophic levels,varies geographically and will change with a moving climate.Annual growth rate of oaks(an ecosystem service in the form of biomass increase and carbon sequestration)was independent of latitude and did not differ between protected and non-protected areas.Our findings question the efficacy of contemporary designation and management of protected oak forests,and emphasize that development and implementation of modified climate smart conservation strategies is needed to safeguard ecosystem functioning,biodiversity,and recreational values of protected forest areas against future challenges. 展开更多
关键词 Biological diversity conservation biology Decision making Forest ecosystems Global warming Species-richness gradients
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Temporal and spatial variation and prediction of water yield and water conservation in the Bosten Lake Basin based on the PLUS-InVEST model
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作者 CHEN Jiazhen KASIMU Alimujiang +3 位作者 REHEMAN Rukeya WEI Bohao HAN Fuqiang ZHANG Yan 《Journal of Arid Land》 SCIE CSCD 2024年第6期852-874,共23页
To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research ... To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research was based on land use/land cover(LULC),natural,socioeconomic,and accessibility data,utilizing the Patch-level Land Use Simulation(PLUS)and Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)models to dynamically assess LULC change and associated variations in water yield and water conservation.The analyses included the evaluation of contribution indices of various land use types and the investigation of driving factors that influence water yield and water conservation.The results showed that the change of LULC in the Bosten Lake Basin from 2000 to 2020 showed a trend of increasing in cultivated land and construction land,and decreasing in grassland,forest,and unused land.The unused land of all the three predicted scenarios of 2030(S1,a natural development scenario;S2,an ecological protection scenario;and S3,a cultivated land protection scenario)showed a decreasing trend.The scenarios S1 and S3 showed a trend of decreasing in grassland and increasing in cultivated land;while the scenario S2 showed a trend of decreasing in cultivated land and increasing in grassland.The water yield of the Bosten Lake Basin exhibited an initial decline followed by a slight increase from 2000 to 2020.The areas with higher water yield values were primarily located in the northern section of the basin,which is characterized by higher altitude.Water conservation demonstrated a pattern of initial decrease followed by stabilization,with the northeastern region demonstrating higher water conservation values.In the projected LULC scenarios of 2030,the estimated water yield under scenarios S1 and S3 was marginally greater than that under scenario S2;while the level of water conservation across all three scenarios remained rather consistent.The results showed that Hejing County is an important water conservation function zone,and the eastern part of the Xiaoyouledusi Basin is particularly important and should be protected.The findings of this study offer a scientific foundation for advancing sustainable development in arid watersheds and facilitating efficient water resource management. 展开更多
关键词 PLUS model InVEST model Bosten Lake Basin water yield water conservation land-use simulation Geodetector
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Effects of ecological soil and water conservation measures on soil erosion control in China’s typical regions:A meta-analysis
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作者 LI Mingming XU Guangzhi +2 位作者 YANG Kaicheng DAI Fuqiang ZHOU Ping 《中国水土保持科学》 CSCD 北大核心 2024年第6期163-175,共13页
[Background]As one of the most serious environmental issues in the world,soil erosion causes water pollution,reservoir siltation,soil productivity decline,thus threatens agricultural systems and even affects global cl... [Background]As one of the most serious environmental issues in the world,soil erosion causes water pollution,reservoir siltation,soil productivity decline,thus threatens agricultural systems and even affects global climate.The benefits of ecological soil and water conservation measures(ESWCMs,such as micro basins tillage and contour tillage)are widely understood,including runoff and soil loss reducing to a certain extent when compared with traditional tillage.While few studies have focused on China’s different soil types and erosion characteristics.[Methods]We reviewed literature from Web of Science,Scopus,and China National Knowledge Infrastructure using terms like“Conservation practice”“Contour tillage”“Runoff”“Sediment”“Erosion”and“China”and retained literatures based on criteria such as natural or simulated precipitation,runoff or soil loss data,reported replications and statistics,recorded factors like location and slope,and at least two data pairs per group.Ultimately,49 literatures were selected to quantify the impacts on different ESWCMs and identify the slope and precipitation for the greatest runoff and sediment reduction by calculating the log response ratio(LRR).[Results]The three regions’soil and water conservation benefits varied due to the differences in climate,terrain,and soil properties:1)ESWCMs applied in the black soil region of Northeast China were the most effective in reducing runoff and soil loss(66.65%runoff and 75.83%sediment),followed by those applied in the purple soil region of Southwest China(39.98%runoff and 58.30%sediment)and loess soil region of Northwest China(16.36%runoff and 32.44%sediment).2)Micro basins tillage(MBT)(71.79%runoff and 87.03%sediment)no-tillage with mulch(NTM)(17.30%runoff and 32.51%sediment),collecting soil to form a ridge with no-till(CSNT)(55.78%runoff and 71.36%sediment reduction)were the most efficient soil and water conservation measures in controlling water erosion in the black soil of Northeast China,the loess soil region of Northwest China and the purple soil region of Southwest China,respectively.3)The slope gradients ranged from 0-3°,>3°-5°and>10°-15°(0-3°:97.09%;>3°-5°:74.62%;and>10°-15°:39.41%)caused the largest reduction of runoff in the black soil region of Northeast China,the loess soil region of Northwest China,and the purple soil region of Southwest China.Meanwhile,the effects of sediment reduction were the most obvious,ranging from 0-3°,>10°-15°,and>20°-25°(0-3°:89.32%;>10°-15°:75.94%;and>20°-25°:67.25%).4)The effect of ESWCMs under rainstorms was the most obvious in the black soil region of Northeast China.The effect on runoff reduction under light rain in the purple soil region of Southwest China was the most obvious,but it failed to pass the significance test in sediment reduction.[Conclusions]The results provided optimal conservation tillage measures for three regions,different slopes and different rainfalls,and provided data support for reducing regional soil and water loss in China. 展开更多
关键词 ecological soil and water conservation measures RUNOFF SEDIMENT water erosion region
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