[Objective] The study was to analyze the forest landscape in Nanling Na- tional Nature Reserve to provide information for the protection of local forest ecosys- tems. [Method] With the documents of 1:10 000 topograph...[Objective] The study was to analyze the forest landscape in Nanling Na- tional Nature Reserve to provide information for the protection of local forest ecosys- tems. [Method] With the documents of 1:10 000 topographic maps, updated Forest Resource Inventory Data, based on the GIS platform and Fragstats software, the paper analyzed the patterns and heterogeneity of forest landscapes by adopting the landscape ecological theory and the method of landscape index. [Result] The forest landscape types, in terms of area occupation from large to small, are in the order of evergreen broad-leaved forest, coniferous mixed forest, evergreen and deciduous broad-leaved mixed forest, shrubs, mixed needle leaf forest, suitable land for forest deciduous broad-leaved forest and non-forest. [Conclusion] Overall, the Reserve had maintained sufficient forest landscape diversity with a low level fragmentation. The distribution of various types of forest landscape was extremely uneven, dominated by several types such as evergreen broad-leaved forest, coniferous forest, etc.展开更多
Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s an...Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s and environ-mental systems.Taking Minqin basin,Gansu Province,as a case,this paper focuses on the evolution of regional physi-cal environments and the cultural sy stems by which people maintain their relationships with those environme nts.This pa-per presents the conceptual framewo rk for the man-land system.Expectin g to accelerate the regional sustain able develop-ment,it also analyses the evolution ary mechanism of regional man-land s ystem.On the basis of reviewing and a nalyzing the evolution of man-land system in Minqin basin,the paper also brings fo rward an adjusting mode for the studi ed area,which consists of three aspects:to b uild up a concept that economic growt h must harmonize with environmental quality’s and land productivity’s improvemen t;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving i rrigation and establish water-saving agricultural system.It’s meanin gful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced and is experiencin g at the global background,and studying its time order and territorial structure,th e system’s character and law of evolu tion,trend and the regulating ways t o improve man-land relationship.展开更多
Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth an...Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth and mortality of 'Medium' and 'Dwarf' forms of squid are derived using the Powell-Wetherall,ELEFAN methods and length-converted catch curves(FiSAT package).Given a lack of commercial exploitation,we assume total mortality to be due entirely to natural mortality.We estimate these squid have fast growth,with growth coefficients(k) ranging from 1.42 to 2.39,and high natural mortality(M),with estimates ranging from 1.61 to 2.92.To sustainably exploit these squid stocks,yield per recruitment based on growth and natural mortality was determined using the Beverton-Holt dynamic pool model.We demonstrate squid stocks could sustain high fishing mortality and low ages at first capture,with an optimal fishing mortality >3.0,with the optimal age at first capture increased to 0.4-0.6 years when fishing mortality approached optimal levels.On the basis of our analyses and estimates of stock biomass,we believe considerable potential exists to expand the squid fishery into the open SCS,relieving fishing pressure on coastal waters.展开更多
Floods have been popularly understood as the nightmares of human beings for their devastation causes. Floods in traditional Vietnamese minds are of the same type since ancient Vietnamese used a metaphor to address the...Floods have been popularly understood as the nightmares of human beings for their devastation causes. Floods in traditional Vietnamese minds are of the same type since ancient Vietnamese used a metaphor to address the floods in Red River Delta (Hanoi area) as un-auspicious marine spirit Thuy Tinh being defeated by the inland spirit Son Tinh in the legendary battle of life. Therefore, as being expressed in many cultures, floods are symbol of death and loss, and human beings have always attempted to get rich of or overcome the floods. However, the floods, under the awareness and pragmatic life of the people of An Giang Province as well as the whole Mekong River Delta (in Southern Vietnam), the floods are considered as the sign of wealth and happiness. What makes the floods to be so auspiciously acknowledged, and how do people manage to ~exploit" the floods to enrich their life? This paper is to investigate and generalize the approaches of utilizing the floods' resources to diversify their life, especially in cuisine culture. The research learns that the regularly stable floods in the Mekong River system strongly and positively affects the life of the local residents, and the community is further wise to exploit and transform the natural resources into their cultural world, mentally and materially, among which, ecotourism is a potentially prospective field展开更多
This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to ...This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to obtain an eddy dataset from 21 years of satellite altimeter data. Analysis revealed that the number of anticyclonic eddies was nearly equal to cyclonic eddies; in the SCS,cyclonic eddies are generally stronger than anticyclonic eddies and anticyclonic eddies are larger and longer-lived than cyclonic eddies. Anticyclonic eddies tend to survive longer in the spring and summer,while cyclonic eddies have longer lifetimes in the autumn and winter. The characteristics and seasonal variations of eddies in the SCS are strongly related to variations in general ocean circulation,in the homogeneity of surface wind stress,and in the unevenness of bottom topography in the SCS. The spatial and temporal variation of mesoscale eddies in the SCS could,therefore,be an important index for understanding local hydrodynamics and regional climate change.展开更多
This article explores the relationship between the tourist's cognition of the landscape experience and the environmental conservation efforts at three distinct tourist sites in mountains of southwestern China. A t...This article explores the relationship between the tourist's cognition of the landscape experience and the environmental conservation efforts at three distinct tourist sites in mountains of southwestern China. A total of 1500 on-site questionnaire surveys were distributed and 1142 valid questionnaires were used for statistical analysis. Results from multi-group path analysis showed that both cognition of the cultural landscape experience and cognition of the natural landscape experience had positive impacts on environmental conservation behaviors and behavior intentions of tourists. Results from comparative analysis among the three tourist sites indicated that cognition of the cultural landscape experience had a stronger power to predict senior environmental conservation behaviors and behavior intentions than cognition of the natural landscape experience, whereas cognition of the natural landscape experience had more power to predict general environmental conservation behaviors and behavior intentions than cognition of the cultural landscape experience. Furthermore, our findings benefit environmental management and sustainabilityat tourist sites.展开更多
[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, ...[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.展开更多
Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiological processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and ch...Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiological processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast biogenesis. Although carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not well understood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death1-1 (spcl-1) and spc1-2. The weak allele spc1-1 mutant showed characteristics of bleached leaves, accumulation of superoxide and mosaic cell death. The strong mutant allele spc1-2 caused a complete arrest of plant growth and development shortly after germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodes a putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed that several major carotenoid compounds downstream of SPC 1/ZDS were substantially reduced in spc1-1, suggesting that SPC 1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll content was decreased in spc1-1 plants. In addition, expression of Lhcb1. 1, Lhcbl. 4 and RbcS was absent in spc1-2, suggesting the possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spc1-1 mutant also displays an ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggest that SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development.展开更多
Willa Cather (1873-1947) is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American s...Willa Cather (1873-1947) is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American southwest. For long Willa Cather's pioneer works have gained great critical acclaim and have been interpreted from different perspectives such as mythicism, romanticism, and feminism. This paper, interpreting Willa C ather' s classical pioneer works of the three periods from the 1920s to the 1930s-My A ntonia ( 1918), A Lost Lady (1923), and "Neighbor Rosicky" (1930), is devoted to making a full exploration into the evolution of her ecological thoughts from an ecofeminist perspective. In Willa Cather's three pioneer works of different creative stages, she deliberately constructs three eco-worlds as a standard of ecological harmony. In her three eco-worlds, Willa Cather not only investigates the relationship between man and nature, but also involves androcentrism, patriarchy, and other ecofeminist topics. Willa Cather's ecological views have undergone changes in her representation of three successive phrases. To interpret Willa Cather's pioneer works from the perspective of ecofeminism can provide a deeper comprehension about her works and her ecological thoughts for the world.展开更多
In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-f...In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-first century projections indicate accelerating climate change and cascading ecological consequences.Effects observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic ecosystems.Rising temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,major changes in composition,structure and function.These changes have prompted action by the conservation community to reduce the adverse effects of climate change.The Southwest Climate Change Initiative(SWCCI),a project led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical tools.The Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change adaptation.Our experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation and restoration of ecosystems so that they continue to provide the services that allow people to thrive in changing environments.展开更多
The paper assesses the economic impacts of the natural forest protection program (NFPP) on the economy of Yunnan Province, China.in terms of gross output, value added,employment, and household income. An inputoutput...The paper assesses the economic impacts of the natural forest protection program (NFPP) on the economy of Yunnan Province, China.in terms of gross output, value added,employment, and household income. An inputoutput model is developed to estimate NFPP's economic impacts by means of backward linkages in the forestry sector and logging and haudage sector. It is found than the NFPP has positive impacts on gross output, value added and houschold income in the initial year, but has significantly negative impacts on the regional economy in the following years as the investment decreases.展开更多
The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, ...The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, the world′s most populous nation supporting some of the most valuable biodiversity hotspots in the world. In this study, we conducted a long-term and large-scale analysis of the effectiveness of 20 of the earliest nature reserves established in Hainan Province, an island home to among the highest concentration of plants and animals in China. Remote sensing imagery from 1988, 1998, and 2008 were analyzed to investigate the temporal and spatial changes of natural forests in these nature reserves and surrounding areas. We also conducted transition matrix analysis and principle component analysis to identify the driving factors that affect the protection effectiveness of nature reserves. The results were as follows: 1) During the 20-year period from 1988 to 2008, natural forests coverage of the 20 studied nature reserves dropped 2.34 percentage points, whereas the natural forests coverage dropped 11.31 percentage points in a 0–5 km outside reserve buffer and 9.36 percentage points in a 5–10 km outside reserve buffer, indicating a significant inhibitory effect of the nature reserves on the loss of natural forests. 2) Natural forests coverage dropped in 60% of the studied nature reserves during the 20-year period, suggesting a poor protection effectiveness of these reserves, while the coverage proportion showed some increase(0%/yr–5%/yr) in other reserves. 3) Expansion of rubber and pulp forests as part of a booming economy were the main factors affecting the effectiveness of the nature reserves for conserving natural forests in Hainan Province. The results of this study provide an important empirical basis for the protection of natural forests in Hainan Province, which can be used as a blueprint for nature reserve evaluation in other places in China.展开更多
This research uses a theoretical conceptual method based on Chantal Mouffe's Radical Democracy which blended with Derrida's deconstruction thesis about "democracy to come" to reach findings on the state of South A...This research uses a theoretical conceptual method based on Chantal Mouffe's Radical Democracy which blended with Derrida's deconstruction thesis about "democracy to come" to reach findings on the state of South Africa's media freedom landscape. The method is contained in the conceptual framework. The article provides the constitutional legal landscape--or the overarching laws of the land--and the co-regulatory framework within which journalists work. There are four research explications: the Protection of State Information Bill (dubbed the Secrecy Bill), a painting of the president and Freedom of Expression, an arson attack on a community radio station and finally, the death of a photojournalist at the hands of police. The argument here is that the death, the arson attack, the Secrecy Bill, and the shut-down of dissent during the exhibition of the painting of the president all undermine democracy and signify significant closures for the media in the now 20-year-old post-apartheid South Africa. The analysis and reflections will be framed within theories of radical democracy, which argue for more fights and contestations and more voices from the margins in order to deepen democracy, rather than rational consensus which closes the spaces for greater plurality.展开更多
While the region of western Guangxi-southeastern Yunan, China, is known and considered prospective for manganese deposits, carrying out prospectivity mapping in this region is challenging due to the diversity of geolo...While the region of western Guangxi-southeastern Yunan, China, is known and considered prospective for manganese deposits, carrying out prospectivity mapping in this region is challenging due to the diversity of geological factors, the complexity of geological process and the asymmetry of geo-information. In this work, the manganese potential mapping for further exploration targeting is implemented via spatial analysis and modal-adaptive prospectivity modeling. On the basis of targeting criteria developed by the mineral system approach, the spatial analysis is leveraged to extract the predictor variables to identify features of the geological process. Specifically, a metallogenic field analysis approach is proposed to extract metallogenic information that quantifies the regional impacts of the synsedimentary faults and sedimentary basins. In the integration of the extracted predictor variables, a modal-adaptive prospectivity model is built, which allows to adapt different data availability and geological process. The resulting prospective areas of high potential not only correspond to the areas of known manganese deposits but also provide a number of favorable targets in the region for future mineral exploration.展开更多
Natural weak acidic groundwater occurs in the unconfined and confined aquifers consisting of Quaternary and Neogene unconsolidated sediments near Beihai in southern Guangxi, China. Under natural conditions the groundw...Natural weak acidic groundwater occurs in the unconfined and confined aquifers consisting of Quaternary and Neogene unconsolidated sediments near Beihai in southern Guangxi, China. Under natural conditions the groundwater has low TDS(less than 200 mg L-1) and low concentrations of trace elements(less than 100 μg L-1) with a deceasing tend in contents of the Lanthanides(rare earth elements, less than 1 μg L-1) towards higher atomic number. The groundwater ranges in p H from 3.33 to 7.0 with an average value of 5.12(even lower than that of local rainwater, 5.88). p H values in the groundwater are a bit higher in rainy seasons than those in dry seasons and do not show significant increasing or decreasing trend with time. The average p H value in groundwater in the confined aquifers is even a bit lower than that in the unconfined aquifer. Comprehensive analyses of the groundwater environment suggest that H+ in the groundwater may be derived from dissociation of H2CO3, release of the absorbed H3O+ in clay layers and the acidity of rainwater. The H2CO3 in the groundwater may be formed by dissolution of CO2(g). Minerals in the unconsolidated sediment are predominated by quartz with small amount of clay minerals. The sediments undergoing a long-term weathering contain low levels of soluble constitutes. Lack of alkaline substances in the groundwater system is also helpful in the accumulation of acidity of the groundwater.展开更多
基金Supported by Digital Monitoring and Management Platform Project in Nanling National Nature Reserve(GDHS13SGHG05025)~~
文摘[Objective] The study was to analyze the forest landscape in Nanling Na- tional Nature Reserve to provide information for the protection of local forest ecosys- tems. [Method] With the documents of 1:10 000 topographic maps, updated Forest Resource Inventory Data, based on the GIS platform and Fragstats software, the paper analyzed the patterns and heterogeneity of forest landscapes by adopting the landscape ecological theory and the method of landscape index. [Result] The forest landscape types, in terms of area occupation from large to small, are in the order of evergreen broad-leaved forest, coniferous mixed forest, evergreen and deciduous broad-leaved mixed forest, shrubs, mixed needle leaf forest, suitable land for forest deciduous broad-leaved forest and non-forest. [Conclusion] Overall, the Reserve had maintained sufficient forest landscape diversity with a low level fragmentation. The distribution of various types of forest landscape was extremely uneven, dominated by several types such as evergreen broad-leaved forest, coniferous forest, etc.
文摘Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s and environ-mental systems.Taking Minqin basin,Gansu Province,as a case,this paper focuses on the evolution of regional physi-cal environments and the cultural sy stems by which people maintain their relationships with those environme nts.This pa-per presents the conceptual framewo rk for the man-land system.Expectin g to accelerate the regional sustain able develop-ment,it also analyses the evolution ary mechanism of regional man-land s ystem.On the basis of reviewing and a nalyzing the evolution of man-land system in Minqin basin,the paper also brings fo rward an adjusting mode for the studi ed area,which consists of three aspects:to b uild up a concept that economic growt h must harmonize with environmental quality’s and land productivity’s improvemen t;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving i rrigation and establish water-saving agricultural system.It’s meanin gful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced and is experiencin g at the global background,and studying its time order and territorial structure,th e system’s character and law of evolu tion,trend and the regulating ways t o improve man-land relationship.
基金Supported by the National Key Technology R&D Program(No.2013BAD13B06)the Guangdong Provincial Program of Science and Technology(No.2014A020217011)+1 种基金funded by the State Oceanic Administration(No.GASI-02-SCS-YSW)supported by a Special Fund for Youth Training from the South China Sea Fisheries Research Institute
文摘Based on the biological data of purpleback flying squid(Sthenoteuthis oualaniensis)collected by light falling-net in the southern South China Sea(SCS) during September to October 2012 and March to April 2013,growth and mortality of 'Medium' and 'Dwarf' forms of squid are derived using the Powell-Wetherall,ELEFAN methods and length-converted catch curves(FiSAT package).Given a lack of commercial exploitation,we assume total mortality to be due entirely to natural mortality.We estimate these squid have fast growth,with growth coefficients(k) ranging from 1.42 to 2.39,and high natural mortality(M),with estimates ranging from 1.61 to 2.92.To sustainably exploit these squid stocks,yield per recruitment based on growth and natural mortality was determined using the Beverton-Holt dynamic pool model.We demonstrate squid stocks could sustain high fishing mortality and low ages at first capture,with an optimal fishing mortality >3.0,with the optimal age at first capture increased to 0.4-0.6 years when fishing mortality approached optimal levels.On the basis of our analyses and estimates of stock biomass,we believe considerable potential exists to expand the squid fishery into the open SCS,relieving fishing pressure on coastal waters.
文摘Floods have been popularly understood as the nightmares of human beings for their devastation causes. Floods in traditional Vietnamese minds are of the same type since ancient Vietnamese used a metaphor to address the floods in Red River Delta (Hanoi area) as un-auspicious marine spirit Thuy Tinh being defeated by the inland spirit Son Tinh in the legendary battle of life. Therefore, as being expressed in many cultures, floods are symbol of death and loss, and human beings have always attempted to get rich of or overcome the floods. However, the floods, under the awareness and pragmatic life of the people of An Giang Province as well as the whole Mekong River Delta (in Southern Vietnam), the floods are considered as the sign of wealth and happiness. What makes the floods to be so auspiciously acknowledged, and how do people manage to ~exploit" the floods to enrich their life? This paper is to investigate and generalize the approaches of utilizing the floods' resources to diversify their life, especially in cuisine culture. The research learns that the regularly stable floods in the Mekong River system strongly and positively affects the life of the local residents, and the community is further wise to exploit and transform the natural resources into their cultural world, mentally and materially, among which, ecotourism is a potentially prospective field
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2013AA09A505)the National Natural Science Foundation of China(No.U1133001)the NSFC-Shandong Joint Fund for Marine Science Research Centers Grant(No.U1406401)
文摘This study focuses on the spatial and temporal distribution characteristics of mesoscale eddies in the South China Sea(SCS). An automatic eddy detection method,based on the geometry of velocity vectors,was adopted to obtain an eddy dataset from 21 years of satellite altimeter data. Analysis revealed that the number of anticyclonic eddies was nearly equal to cyclonic eddies; in the SCS,cyclonic eddies are generally stronger than anticyclonic eddies and anticyclonic eddies are larger and longer-lived than cyclonic eddies. Anticyclonic eddies tend to survive longer in the spring and summer,while cyclonic eddies have longer lifetimes in the autumn and winter. The characteristics and seasonal variations of eddies in the SCS are strongly related to variations in general ocean circulation,in the homogeneity of surface wind stress,and in the unevenness of bottom topography in the SCS. The spatial and temporal variation of mesoscale eddies in the SCS could,therefore,be an important index for understanding local hydrodynamics and regional climate change.
基金financially supported by National Natural Science Foundation of China (Grant No. 41171121, Grant No. 41301134)
文摘This article explores the relationship between the tourist's cognition of the landscape experience and the environmental conservation efforts at three distinct tourist sites in mountains of southwestern China. A total of 1500 on-site questionnaire surveys were distributed and 1142 valid questionnaires were used for statistical analysis. Results from multi-group path analysis showed that both cognition of the cultural landscape experience and cognition of the natural landscape experience had positive impacts on environmental conservation behaviors and behavior intentions of tourists. Results from comparative analysis among the three tourist sites indicated that cognition of the cultural landscape experience had a stronger power to predict senior environmental conservation behaviors and behavior intentions than cognition of the natural landscape experience, whereas cognition of the natural landscape experience had more power to predict general environmental conservation behaviors and behavior intentions than cognition of the cultural landscape experience. Furthermore, our findings benefit environmental management and sustainabilityat tourist sites.
文摘[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.
基金grants from National Natural Science Foundation of China (Grant Nos. 30330360, 30125025 , 30221002) Chinese Academy of Sciences (Grant No. KSCX2- YW-N-015)
文摘Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiological processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast biogenesis. Although carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not well understood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death1-1 (spcl-1) and spc1-2. The weak allele spc1-1 mutant showed characteristics of bleached leaves, accumulation of superoxide and mosaic cell death. The strong mutant allele spc1-2 caused a complete arrest of plant growth and development shortly after germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodes a putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed that several major carotenoid compounds downstream of SPC 1/ZDS were substantially reduced in spc1-1, suggesting that SPC 1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll content was decreased in spc1-1 plants. In addition, expression of Lhcb1. 1, Lhcbl. 4 and RbcS was absent in spc1-2, suggesting the possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spc1-1 mutant also displays an ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggest that SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development.
文摘Willa Cather (1873-1947) is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American southwest. For long Willa Cather's pioneer works have gained great critical acclaim and have been interpreted from different perspectives such as mythicism, romanticism, and feminism. This paper, interpreting Willa C ather' s classical pioneer works of the three periods from the 1920s to the 1930s-My A ntonia ( 1918), A Lost Lady (1923), and "Neighbor Rosicky" (1930), is devoted to making a full exploration into the evolution of her ecological thoughts from an ecofeminist perspective. In Willa Cather's three pioneer works of different creative stages, she deliberately constructs three eco-worlds as a standard of ecological harmony. In her three eco-worlds, Willa Cather not only investigates the relationship between man and nature, but also involves androcentrism, patriarchy, and other ecofeminist topics. Willa Cather's ecological views have undergone changes in her representation of three successive phrases. To interpret Willa Cather's pioneer works from the perspective of ecofeminism can provide a deeper comprehension about her works and her ecological thoughts for the world.
文摘In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-first century projections indicate accelerating climate change and cascading ecological consequences.Effects observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic ecosystems.Rising temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,major changes in composition,structure and function.These changes have prompted action by the conservation community to reduce the adverse effects of climate change.The Southwest Climate Change Initiative(SWCCI),a project led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical tools.The Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change adaptation.Our experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation and restoration of ecosystems so that they continue to provide the services that allow people to thrive in changing environments.
文摘The paper assesses the economic impacts of the natural forest protection program (NFPP) on the economy of Yunnan Province, China.in terms of gross output, value added,employment, and household income. An inputoutput model is developed to estimate NFPP's economic impacts by means of backward linkages in the forestry sector and logging and haudage sector. It is found than the NFPP has positive impacts on gross output, value added and houschold income in the initial year, but has significantly negative impacts on the regional economy in the following years as the investment decreases.
基金Under the auspices of Nationwide Remote Sensing Survey and Evaluation on Ecological Environment Change in 2000–2010(No.STSN-04-00)
文摘The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, the world′s most populous nation supporting some of the most valuable biodiversity hotspots in the world. In this study, we conducted a long-term and large-scale analysis of the effectiveness of 20 of the earliest nature reserves established in Hainan Province, an island home to among the highest concentration of plants and animals in China. Remote sensing imagery from 1988, 1998, and 2008 were analyzed to investigate the temporal and spatial changes of natural forests in these nature reserves and surrounding areas. We also conducted transition matrix analysis and principle component analysis to identify the driving factors that affect the protection effectiveness of nature reserves. The results were as follows: 1) During the 20-year period from 1988 to 2008, natural forests coverage of the 20 studied nature reserves dropped 2.34 percentage points, whereas the natural forests coverage dropped 11.31 percentage points in a 0–5 km outside reserve buffer and 9.36 percentage points in a 5–10 km outside reserve buffer, indicating a significant inhibitory effect of the nature reserves on the loss of natural forests. 2) Natural forests coverage dropped in 60% of the studied nature reserves during the 20-year period, suggesting a poor protection effectiveness of these reserves, while the coverage proportion showed some increase(0%/yr–5%/yr) in other reserves. 3) Expansion of rubber and pulp forests as part of a booming economy were the main factors affecting the effectiveness of the nature reserves for conserving natural forests in Hainan Province. The results of this study provide an important empirical basis for the protection of natural forests in Hainan Province, which can be used as a blueprint for nature reserve evaluation in other places in China.
文摘This research uses a theoretical conceptual method based on Chantal Mouffe's Radical Democracy which blended with Derrida's deconstruction thesis about "democracy to come" to reach findings on the state of South Africa's media freedom landscape. The method is contained in the conceptual framework. The article provides the constitutional legal landscape--or the overarching laws of the land--and the co-regulatory framework within which journalists work. There are four research explications: the Protection of State Information Bill (dubbed the Secrecy Bill), a painting of the president and Freedom of Expression, an arson attack on a community radio station and finally, the death of a photojournalist at the hands of police. The argument here is that the death, the arson attack, the Secrecy Bill, and the shut-down of dissent during the exhibition of the painting of the president all undermine democracy and signify significant closures for the media in the now 20-year-old post-apartheid South Africa. The analysis and reflections will be framed within theories of radical democracy, which argue for more fights and contestations and more voices from the margins in order to deepen democracy, rather than rational consensus which closes the spaces for greater plurality.
基金Project(2017YFC0601503)supported by the National Key R&D Program of ChinaProjects(41772349,41972309,41472301,41772348)supported by the National Natural Science Foundation of China。
文摘While the region of western Guangxi-southeastern Yunan, China, is known and considered prospective for manganese deposits, carrying out prospectivity mapping in this region is challenging due to the diversity of geological factors, the complexity of geological process and the asymmetry of geo-information. In this work, the manganese potential mapping for further exploration targeting is implemented via spatial analysis and modal-adaptive prospectivity modeling. On the basis of targeting criteria developed by the mineral system approach, the spatial analysis is leveraged to extract the predictor variables to identify features of the geological process. Specifically, a metallogenic field analysis approach is proposed to extract metallogenic information that quantifies the regional impacts of the synsedimentary faults and sedimentary basins. In the integration of the extracted predictor variables, a modal-adaptive prospectivity model is built, which allows to adapt different data availability and geological process. The resulting prospective areas of high potential not only correspond to the areas of known manganese deposits but also provide a number of favorable targets in the region for future mineral exploration.
基金supported by the National Natural Science Foundation of China (41172227, 40172087)the Project of Development Field of High Priority of the Specialized Research Fund for the Doctoral Program of Higher Education of China (20110022130002)
文摘Natural weak acidic groundwater occurs in the unconfined and confined aquifers consisting of Quaternary and Neogene unconsolidated sediments near Beihai in southern Guangxi, China. Under natural conditions the groundwater has low TDS(less than 200 mg L-1) and low concentrations of trace elements(less than 100 μg L-1) with a deceasing tend in contents of the Lanthanides(rare earth elements, less than 1 μg L-1) towards higher atomic number. The groundwater ranges in p H from 3.33 to 7.0 with an average value of 5.12(even lower than that of local rainwater, 5.88). p H values in the groundwater are a bit higher in rainy seasons than those in dry seasons and do not show significant increasing or decreasing trend with time. The average p H value in groundwater in the confined aquifers is even a bit lower than that in the unconfined aquifer. Comprehensive analyses of the groundwater environment suggest that H+ in the groundwater may be derived from dissociation of H2CO3, release of the absorbed H3O+ in clay layers and the acidity of rainwater. The H2CO3 in the groundwater may be formed by dissolution of CO2(g). Minerals in the unconsolidated sediment are predominated by quartz with small amount of clay minerals. The sediments undergoing a long-term weathering contain low levels of soluble constitutes. Lack of alkaline substances in the groundwater system is also helpful in the accumulation of acidity of the groundwater.