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| 1 | Recent progresses in mangrove conservation,restoration and research in China显示文摘Aims In this paper,we highlighted some key progresses in mangrove conservation,restoration and research in China during last two decades.Methods Based on intensive literature review,we compared the distribution and areas of existing mangroves among selected provinces of China,discussed the issues associated with mangrove conservation and restoration and highlighted major progresses on mangrove research conducted by key institutions or universities in China's Mainland,Hong Kong,Taiwan and Macao.Important findings The population boom and rapid economic developments have greatly reduced mangrove areas in China since 1980s,leaving only 22700 ha mangroves in China's Mainland in 2001.Chinese government has launched a series of programs to protect mangroves since 1980s and has established mangrove ecosystems as high-priority areas for improving environmental and living resource management.During last three decades,a total of 34 natural mangrove conservation areas have been established,which accounts for 80%of the total existing mangroves areas in China.Mangrove restoration areas in China' Mainland accounted for<7%of the total mangroves areas in 2002.A great deal of research papers on Chinese mangroves has been published in international journals.However,more systematic protection strategies and active restoration measurements are still urgently needed in order to preserve these valuable resources in China. | Luzhen Chen Wenqing Wang Yihui Zhang Guanghui Lin | 2009 | Journal of Plant Ecology2009，2，2： | 42 |
| 2 | Mathematical Models for Combined Refraction-Diffraction of Waves on Non-Uniform Current and Depth显示文摘Two mathematical models for combined refraction-diffraction of regular and irregular waves on non-uniform current in water of slowly varying topography are presented in this paper. Model I is derived by wave theory and variational principle separately. It has two kinds of expressions including the dissipation term. Model n is based on the energy conservation equation with energy flux through the wave crest lines in orthogonal curvilinear coordinates and the wave kinematic conservation equation. The analysis and comparison and special cases of these two models are also given. | Hong Guangwen Professor, Research Institute of Coastal and Ocean Engineering, Hohai University, 1 Xikang Road, Nanjing 210024 | 1996 | China Ocean Engineering1996，11，4： | 35 |
| 3 | The Noether's Theory of Birkhoffian Systems~*显示文摘By using the generalized quasi-symmetry of the infinitesimal transformation of the transformation group G_r, the Noether’s theory for Birkhoffian systems (including Noether’s theorem and its inverse) has been established. An example is given. | 梅凤翔 | 1993 | Science China Mathematics1993，36，12： | 25 |
| 4 | U.S. GEOLOGICAL SURVEY PROGRAMS AND INVESTIGATIONS RELATED TO SOIL AND WATER CONSERVATION显示文摘The U.S. Geological Survey has a rich tradition of collecting hydrologic data, especially for fluxes of water and suspended sediment, that provide a foundation for studies of soil and water conservation. Applied and basic research has included investigations of the effects of land use on rangelands, croplands, and forests; hazards mapping; derivation of flood and drought frequency, and other statistics related to streamflow and reservoir storage; development and application of models of rainfall-runoff relations, chemical quality, and sediment movement; and studies of the interactive processes of overland and channel flow with vegetation. Networks of streamgaging stations and (or) sampling sites within numerous drainage basins are yielding information that extends databases and enhances the ability to use those data for interpretive studies. | W. R. OSTERKAMP and J. R. GRAY Research Hydrologist, U. S. Geological Survey, 1675 W. Anklam Road, Tucson, AZ 85745 U. S. A. Hydrologist, U. S. Geological Survey, 415 National Center, Reston, VA 20192 U. S. A. | 2001 | International Journal of Sediment Research2001，16，3： | 22 |
| 5 | Patterns of shrub species richness and abundance in relation to environmental factors on the Alxa Plateau:Prerequisites for conserving shrub diversity in extreme arid desert regions显示文摘Shrub species are considered the dominant plants in arid desert ecosystems,unlike in semiarid steppe zones or in grassland ecosystems.On the Alxa Plateau,northern China,sparse vegetation with cover ranging from 15% to 30% is characterized mainly by multifarious shrubs because herbaceous species are strongly restricted by the extreme drought climate,wind erosion,overgrazing and sand burial.Patterns in shrub species richness and species abundance in relation to environmental conditions were examined by DCA(detrended correspondence analysis) and interpreted by a biplot.The rela-tionships between species diversity and environmental factors were examined using regression analyses.Our results show that the distributions of the shrub species in response to environmental conditions can be grouped into four ecological types,corresponding with the biological traits of the shrubs and their responses to the gradients of soil texture and soil water content.Patterns in species richness and species abundance were mainly determined by the deeper soil water content,instead of the soil texture as hypothesized by numerous studies in semiarid grasslands.With exception of the deeper soil water content,soil organic matter and total N content were positively correlated with species abundance,while pH was negatively correlated with it.These findings imply that it is vital for cur-rent shrub diversity conservation to reduce agricultural water use in the middle reaches of the Heihe River,which supplies water for the lower reaches in the western parts of the plateau,and to reduce the amount of groundwater exploitation and urban and oasis water use,to increase the water supply from Helan Mountain to the eastern desert of the Alxa Plateau. | XinRong Li HuiJuan Tan MingZhu He XinPing Wang XiaoJun Li | 2009 | Science China Earth Sciences2009，52，5： | 17 |
| 6 | NOETHER’S THEOREM AND ITS INVERSE OF NONHOLONOMIC NONCONSERVATIVE DYNAMICAL SYSTEMS显示文摘Noether’s theorem and its inverse of nonconservative systems subject to first-ordernonlinear nonholonomic constraints are obtained by introducing the generalized quasi-symmetry of the infinitesimal transformation of the group of transformations G_t for thegiven dynamical systems. | 刘端 | 1991 | Science China Mathematics1991，34，4： | 17 |
| 7 | The impacts of conservation agriculture on crop yield in China depend on specific practices, crops and cropping regions显示文摘For smooth and wide application of conservation agriculture(CA), remaining uncertainties about its impacts on crop yield need to be reduced. Based on previous field experiments in China, a meta-analysis was performed to quantify the actual impacts of CA practices(NT: no/reduced-tillage only, CTSR: conventional tillage with straw retention, NTSR: NT with straw retention) on crop yields as compared to conventional tillage without straw retention(CT).Although CA practices increased crop yield by 4.6% on average, there were large variations in their impacts. For each CA practice, CTSR and NTSR significantly increased crop yield by 4.9%and 6.3%, respectively, compared to CT. However, no significant effect was found for NT. Among ecological areas, significant positive effects of CA practices were found in areas with an annual precipitation below 600 mm. Similar effects were found in areas with annual mean air temperature above 5 °C. For cropping regions, CA increased crop yield by 6.4% and 5.5%compared to CT in Northwest and South China, respectively, whereas no significant effects were found in the North China and Northeast China regions. Among crops, the positive effects of CA practices were significantly higher in maize(7.5%) and rice(4.1%) than in wheat(2.9%). NT likely decreased wheat yield. Our results indicate that there are great differences in the impacts of CA practices on crop yield, owing to regional variation in climate and crop types. CA will most likely increase maize yield but reduce wheat yield. It is strongly recommended to apply CA with crop straw retention in maize cropping areas and seasons with a warm and dry climate pattern. | Chengyan Zheng Yu Jiang Changqing Chen Yanni Sun Jinfei Feng Aixing Deng Zhenwei Song Weijian Zhang | 2014 | The Crop Journal2014，2，5： | 15 |
| 8 | Cenozoic topography,monsoons and biodiversity conservation within the Tibetan Region:An evolving story显示文摘The biodiversity of the Himalaya,Hengduan Mountains and Tibet,here collectively termed the Tibetan Region,is exceptional in a global context.To contextualize and understand the origins of this biotic richness,and its conservation value,we examine recent fossil finds and review progress in understanding the orogeny of the Tibetan Region.We examine the deep-time origins of monsoons affecting Asia,climate variation over different timescales,and the establishment of environmental niche heterogeneity linked to topographic development.The origins of the modern biodiversity were established in the Eocene,concurrent with the formation of pronounced topographic relief across the Tibetan Region.High(>4 km)mountains to the north and south of what is now the Tibetan Plateau bounded a Paleogene central lowland(<2.5 km)hosting moist subtropical vegetation influenced by an intensifying monsoon.In mid Miocene times,before the Himalaya reached their current elevation,sediment infilling and compressional tectonics raised the floor of the central valley to above 3000 m,but central Tibet was still moist enough,and low enough,to host a warm temperate angiosperm-dominated woodland.After 15 Ma,global cooling,the further rise of central Tibet,and the rain shadow cast by the growing Himalaya,progressively led to more open,herb-rich vegetation as the modern high plateau formed with its cool,dry climate.In the moist monsoonal Hengduan Mountains,high and spatially extensive since the Eocene but subsequently deeply dissected by river incision,Neogene cooling depressed the tree line,compressed altitudinal zonation,and created strong environmental heterogeneity.This served as a cradle for the then newly-evolving alpine biota and favoured diversity within more thermophilic vegetation at lower elevations.This diversity has survived through a combination of minimal Quaternary glaciation,and complex relief-related environmental niche heterogeneity.The great antiquity and diversity of the Tibetan Region biota argues for its conservation,and the importance of that biota is demonstrated through our insights into its long temporal gestation provided by fossil archives and information written in surviving genomes.These data sources are worthy of conservation in their own right,but for the living biotic inventory we need to ask what it is we want to conserve.Is it 1)individual taxa for their intrinsic properties,2)their services in functioning ecosystems,or 3)their capacity to generate future new biodiversity?If 2 or 3 are our goal then landscape conservation at scale is required,and not just seed banks or botanical/zoological gardens. | Robert A.Spicer Alexander Farnsworth Tao Su | 2020 | Plant Diversity2020，42，4： | 14 |
| 9 | Estimating farmers’stated willingness to accept pay for ecosystem services:case of Lake Naivasha watershed Payment for Ecosystem Services scheme-Kenya显示文摘Introduction:Lake Naivasha watershed is recognized for its contribution to Kenya’s national gross domestic product from the export of horticultural products.Commercial horticultural investment downstream depends mainly on the Lake’s water.The fresh water lake lacks surface outflow,and its recharge depends on river Malewa flowing from upper catchment in Aberdare ranges.However,unsustainable land use practices in the upper catchment has led to increasing sediment loading and pollution in river Malewa which affects water quality in the Lake downstream.Payment for Environmental Services(PES)scheme has been initiated as an alternative incentive approach to motivate upstream smallholder farmers adopt sustainable land use practices for conservation of watershed services.This paper analyzes willingness to accept pay(WTA)as proxy economic measure of environmental service(ES)value and determines socio-economic factors influencing farmers WTA for watershed conservation.We analyzed the WTA and characterized WTA underlying socio-economic determinants in two PES intervention sites in Kenya.Methods:The objective of this study was to estimate WTA and determine socio-economic factors influencing WTA.Semi-structured questionnaire was used to collect data from 200 PES farmers through face-to-face interview.We applied contingent valuation(CV)and logistic regression for data analyses to elicit farmer’s WTA estimates to implement PES farm practices and determine socio-economic factors influencing WTA,respectively.Results:Results revealed over 90% of respondents were farmers and 60% had primary level of education.Average household farm size was 2.305 acres and family size was six members on average.We recorded a monthly marginal household increase in gross income from Kshs.6891.969(US$68.92)before PES to Kshs.11,011.48(US$110.12)with PES interventions.The estimated annual lowest and highest WTA for PES farm practices were at Kshs.8835(US$88.35)for grass strip and Kshs.21,847.500(US$218.48)for fallowing.Household socio-economic characteristics had significant influence on WTA among farmers.Conclusions:The study revealed heterogeneity in WTA estimates among PES implementing farmers.The WTA reflects opportunity cost to farmers.We recommend PES mechanism as a policy tool to internalize negative watershed externalities to provide ecosystem services. | J.M.Nyongesa H.K.Bett J.K.Lagat O.I.Ayuya | 2016 | Ecological Processes2016，5，1： | 13 |
| 10 | Conservation needs of amphibians in China: A review显示文摘The conservation status of all the amphibians in China is analyzed,and the country is shown to be a global priority for conservation in comparison to many other countries of the world.Three Chinese regions are particularly rich in amphibian diversity:Hengduan,Nanling,and Wuyi mountains.Sala-manders are more threatened than frogs and toads.Several smaller families show a high propensity to become seriously threatened:Bombinatoridae,Cryptobranchidae,Hynobiidae and Salamandridae.Like other parts of the world,stream-breeding,high-elevation forest amphibians have a much higher likeli-hood of being seriously threatened.Habitat loss,pollution,and over-harvesting are the most serious threats to Chinese amphibians.Over-harvesting is a less pervasive threat than habitat loss,but it is more likely to drive a species into rapid decline.Five conservation challenges are mentioned with recommendations for the highest priority research and conservation actions. | Michael Wai Neng LAU Simon N STUART Janice S CHANSON Neil A COX Debra L FISCHMAN | 2007 | Science China(Life Sciences)2007，50，2： | 12 |
| 11 | Noether-type theorem for discrete nonconservative dynamical systems with nonregular lattices显示文摘We investigate Noether symmetries and conservation laws of the discrete nonconserved systems with nonregular lattices. The operators of discrete transformation and discrete differentiation to the right and left are introduced for the systems. Based on the invariance of discrete Hamilton action on nonregular lattices of the systems with the nonconserved forces under the infinitesimal transformations with respect to the time and generalized coordinates, we give the discrete analog of generalized variational formula. From this formula we derive the discrete analog of generalized Noether-type identity, and then we present the generalized quasi-extremal equations and properties of these equations for the systems. We also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the systems. We discuss an example to illustrate these results. | FU JingLi1, CHEN LiQun2 & CHEN BenYong3 1 Institute of Mathematical Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China 2 Department of Mechanics, Shanghai University, Shanghai 200072, China 3 Faculty of Mechanical-Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou 310018, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，3： | 11 |
| 12 | Developmental Tendency of Dry Land Farming Technologies显示文摘The developmental tendency of dry land farming technologies in the semiarid area of China were reviewed based on the overview of recent progress in dry land farming researches from China and oversea. It was emphasized that conservation tillage, limited irrigation, genetic modification and chemical control are the important aspects for the dry land farming research and development of the future. In addition, some considerations and suggestions on above-mentioned aspects were proposed in this paper. | SHAN Lun(Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, P. R . China ) | 2002 | Agricultural Sciences in China2002，1，8： | 10 |
| 13 | Conservation metagenomics: a new branch of conservation biology显示文摘Multifaceted approaches are required to monitor wildlife populations and improve conservation efforts. In the last decade,increasing evidence suggests that metagenomic analysis offers valuable perspectives and tools for identifying microbial communities and functions. It has become clear that gut microbiome plays a critical role in health, nutrition, and physiology of wildlife, including numerous endangered animals in the wild and in captivity. In this review, we first introduce the human microbiome and metagenomics, highlighting the importance of microbiome for host fitness. Then, for the first time, we propose the concept of conservation metagenomics, an emerging subdiscipline of conservation biology, which aims to understand the roles of the microbiota in evolution and conservation of endangered animals. We define what conservation metagenomics is along with current approaches, main scientific issues and significant implications in the study of host evolution, physiology,nutrition, ecology and conservation. We also discuss future research directions of conservation metagenomics. Although there is still a long way to go, conservation metagenomics has already shown a significant potential for improving the conservation and management of wildlife. | Fuwen Wei Qi Wu Yibo Hu Guangping Huang Yonggang Nie Li Yan | 2019 | Science China(Life Sciences)2019，62，2： | 10 |
| 14 | MULTI-DIMENSIONAL RIEMANN PROBLEM OF SCALAR CONSERVATION LAW显示文摘This paper considers multi-dimensional Riemann problem in another kind of view. The author gets solution of (1.1)(1.2) in Theorem 3.4 and proves its uniqueness. A new method of solution constructing is applied, which is different from the usual self-similar transformation. The author also discusses some generalized concepts in multi-dimensional situation (such as 'convex condition', 'left value' and 'right value', etc). An example is finally given to demonstrate that rarefaction wave solution of (1 .1)(1 .2) is not self-similar. | 杨小舟 | 1999 | Acta Mathematica Scientia1999，19，2： | 10 |
| 15 | Local structure-preserving algorithms for partial differential equations显示文摘In this paper, we discuss the concept of local structure-preserving algorithms (SPAs) for partial differential equations, which are the natural generalization of the corresponding global SPAs. Local SPAs for the problems with proper boundary conditions are global SPAs, but the inverse is not necessarily valid. The concept of the local SPAs can explain the difference between different SPAs and provide a basic theory for analyzing and constructing high performance SPAs. Furthermore, it enlarges the applicable scopes of SPAs. We also discuss the application and the construction of local SPAs and derive several new SPAs for the nonlinear Klein-Gordon equation. | WANG YuShun WANG Bin QIN MengZhao | 2008 | Science China Mathematics2008，51，11： | 10 |
| 16 | A review of extractive distillation from an azeotropic phenomenon for dynamic control显示文摘Extractive distillation is an effective method for separating azeotropic or close boiling point mixtures by adding a third component.Various technologies for performing the extractive distillation process have been explored to protect the environment and save resources.This paper focuses on the improvement of these advanced technologies in recent years.Extractive distillation is retrieved and analyzed from the view of phase equilibrium,selection of solvent in extractive distillation,process design,energy conservation,and dynamic control.The quantitative structure–property relationship used in extractive distillation is discussed,and the future development of extractive distillation is proposed to determine how the solvent affects the relative volatility of the separated mixture.In the steady state design,the relationship between the curvature of the residue curve and parameters of the optimal steady state is also highlighted as another field worthy of further study to simplify the distillation process. | Yixin Ma Peizhe Cui Yongkun Wang Zhaoyou Zhu Yinglong Wang Jun Gao | 2019 | Chinese Journal of Chemical Engineering2019，27，7： | 9 |
| 17 | Changes in biodiversity and ecosystem function during the restoration of a tropical forest in south china显示文摘Tropical forests continue to vanish rapidly,but few long-term studies have ever examined if and how the lost forests can be restored.Based on a 45-year restoration study in south China,we found that a tropical rain forest,once completely destroyed,could not recover naturally without deliberate restoration efforts.We identified two kinds of thresholds that must be overcome with human ameliorative measures before the ecosystem was able to recover.The first threshold was imposed primarily by extreme physical conditions such as exceedingly high surface temperature and impoverished soil,while the second was characterized by a critical level of biodiversity and a landscape context that accommodates dispersal and colonization processes.Our three treatment catchments(un-restored barren land,single-species plantation,and mixed-forest stand)exhibited dramatically different changes in biodiversity and ecosystem functioning over 4 decades.The mixed forest,having the highest level of biodiversity and ecosystem functioning,possesses several major properties of tropical rain forest.These findings may have important implications for the restoration of many severely degraded or lost tropical forest ecosystems. | REN Hai,LI ZhiAn,SHEN WeiJun,YU ZuoYue,PENG ShaoLin,LIAO ChongHui,DING MingMao & WU JianGuo 1 South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China 2 Institute of Ecology and Evolution,Zhongshan University,Guangzhou 510275,China 3 Guangdong Institute of Entomology,Guangzhou 510275,China 4 School of Life Sciences and Global Institute of Sustainability,Arizona State University,Tempe,AZ 85287,USA | 2007 | Science China(Life Sciences)2007，50，2： | 9 |
| 18 | NOTES ON FINITE ELEMENT METHOD AND ITS GENERALIZATION显示文摘NOTES ON FINITE ELEMENT METHOD AND ITS GENERALIZATIONNOTESONFINITEELEMENTMETHODANDITSGENERALIZATION￥L.Tao(InstituteofMechanic... | L. Tao (Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, P. R. China)G. Q. Chen (Center for Environmental Sciences, Peking University, Beijing 100871, P. R. China)K. R. Rajagopal (Department of Mechanical Engineering, University of Pit | 1996 | Journal of Hydrodynamics1996，8，3： | 9 |
| 19 | Bird diversity and waterbird habitat preferences in relation to wetland restoration at Dianchi Lake, south-west China显示文摘Background:Restoration projects have been implemented worldwide to mitigate the adverse effects of the loss and degradation of wetland habitats.Much research has been carried out on the impacts on birds of wetland restoration and management projects in China. Studies have mainly investigated central or coastal wetlands,while inland wetlands in remote areas have been much less studied. We focused on examining the response of wild birds to wetland restoration in Dianchi Lake,south-west China. Methods: The line transect method was performed at 26 sampling plots.Three of these were in the city,and to acquire all wild bird data 23 plots were located every 2-8 km along the shore of Dianchi Lake, between December 2011 and November 2013.We collected all related bird records by searching the available literature, articles, newspapers and records of birdwatchers to compare species variation before and after implementation of wetland restoration.To measure the relationships between waterbird assemblages and habitat structures, we used canonical correspondence analysis (CCA) to pair the main matrix of bird assemblages with a second matrix of habitat variables. Results: We recorded 182 bird species belonging to 51 families and 17 orders. Of the species, 42 were new records for Kunming City and 20 were new records for Yunnan Province. Ten waterbird species were found to have disappeared from the shore of Dianchi Lake.CCA results indicated that waterbirds could be divided into four categories based on their habitat preference:synanthropic (wintering gulls), special habitat (shorebirds),semi-natural (wintering coots and ducks) and disturbance-tolerant (resident) species.Conclusions:Our study is the first to consider the entire wild bird community throughout the year and discuss the species variation before and after wetland restoration projects launched for Dianchi Lake.Distinct habitat requirements of different waterbird groups were detected in our study,suggesting different types of restoration and management should be implemented. | Kang Luo Zhaolu Wu Haotian Bai Zijiang Wang | 2019 | Avian Research2019，10，3： | 9 |
| 20 | A semi-implicit semi-Lagrangian global nonhydrostatic model and the polar discretization scheme显示文摘The Global/Regional Assimilation and PrEdiction System(GRAPES) is a newly developed global non-hydrostatic numerical prediction model,which will become the next generation medium-range opera-tional model at China Meteorological Administration(CMA).The dynamic framework of GRAPES is featuring with fully compressible equations,nonhydrostatic or hydrostatic optionally,two-level time semi-Lagrangian and semi-implicit time integration,Charney-Phillips vertical staggering,and complex three-dimensional pre-conditioned Helmholtz solver,etc.Concerning the singularity of horizontal momentum equations at the poles,the polar discretization schemes are described,which include adoption of Arakawa C horizontal grid with ν at poles,incorporation of polar filtering to maintain the computational stability,the correction to Helmholtz equation near the poles,as well as the treatment of semi-Lagrangian interpolation to improve the departure point accuracy,etc.The balanced flow tests validate the rationality of the treatment of semi-Lagrangian departure point calculation and the polar discretization during long time integration.Held and Suarez tests show that the conservation proper-ties of GRAPES model are quite good. | YANG XueSheng1,CHEN JiaBin2,HU JiangLin1,CHEN DeHui1,SHEN XueShun1,ZHANG HongLiang1 1 State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China 2 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Beijing 100029,China | 2007 | Science China Earth Sciences2007，50，12： | 9 |
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