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What is attractive rural landscape?Differences in the social and expert assessment of the changes in the rural landscape of the Carpathian region in Poland with regard to the need of its protection
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作者 Agata GAJDEK Barbara KRUPA Anna NOWAK 《Journal of Mountain Science》 SCIE CSCD 2023年第2期501-515,共15页
Contemporary villages of the mountain region are subject to uncontrolled structural and spatial transformations,which cause deformation of centuries-old spatial systems of high cultural and natural value.The aim of th... Contemporary villages of the mountain region are subject to uncontrolled structural and spatial transformations,which cause deformation of centuries-old spatial systems of high cultural and natural value.The aim of the study is to confront the opinions of the inhabitants and experts regarding the condition of the cultural landscape of the villages in south-eastern Poland.This area belongs to the Carpathian region of Central Europe.The historical and economic conditions of the studied region,related to the functioning in the post-war period,and then its breakdown and the development of the free market economy,constitute an interesting background for the proposed research.Local communities still remembering the period of difficulties related to the period of systemic transformations,are currently experiencing a relative prosperity,many difficulties related to the period of systemic transformations,are currently experiencing a relative prosperity,which is also expressed in a completely new,previously unknown way of managing the landscape.Investments implemented in villages are associated by the inhabitants with the improvement of the standards and quality of life.They assess them rather positively.An expert assessment of these landscape transformations indicates their negative dimension and the risk of losing timeless values.The discrepancy in the assessment of experts and local residents creates difficulties in the protection of the rural landscape.Therefore,high-quality visual landscape features among rural residents is necessary from the point of view of its multi-faceted and effective protection.Local initiatives and actions in the field of industry policy should play a significant role in this respect by consolidating the images of a harmonious landscape in the public awareness. 展开更多
关键词 Polish village Landscape attractiveness Cultural landscape Spatial systems
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Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily
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作者 Cong Gao Shiqi Li +4 位作者 Yunchen Xu Yue Liu Yiping Xia Ziming Ren Yun Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期545-555,共11页
Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellul... Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch. 展开更多
关键词 Lilium brownii var.giganteum LbgCWIN1 Phylogenetic analysis Promoter analysis Bulblet initiation
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Recreational Behavior and Spatial Characteristics of Urban Parks Based on Multi-Source Information: A Case Study of Xiaohong Stone Carving Park in Nanjing
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作者 XIANG Linkang WANG Xiaojun 《Journal of Landscape Research》 2024年第2期6-14,共9页
Urban parks are an important part of urban recreational spaces,and the development of analysis framework of recreational behavior and space is helpful for the design of urban parks to better meet the activity and usag... Urban parks are an important part of urban recreational spaces,and the development of analysis framework of recreational behavior and space is helpful for the design of urban parks to better meet the activity and usage requirements of visitors.In this paper,Xiaohong Stone Carving Park in Nanjing was taken as the research object to explore the relationship between landscape space and user behavior for design feedback.The orthographic image technology of unmanned aerial vehicle(UAV)and machine deep learning were used to analyze users behavior activities in the park,and the spatial characteristics of each node in the park were evaluated by semantic differential scale to explore the potential causes of behavior activities.The results showed that①there were significant differences in the number of visitors on holidays and working days,and young people and children were the main users.②The users activity of the park differed greatly on the inner and outer tour roads,and the users showed stronger willingness to stay on the inner tour roads.Recreational activities received more attention than cultural ones.③The overall distribution of users was significantly affected by hydrophilicity,and the recreational behavior and activity type were affected by multiple factors which include the hydrophilicity,safety,accessibility of cultural relics and the amount of recreational facilities.Finally,the enhanced strategies such as improving the cultural tour system,establishing hydrophilic safety belts and optimizing recreational facilities were put forward. 展开更多
关键词 Urban park Recreational behavior Landscape space Machine learning UAV
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Exploring the rules of cropland elevation uplift in China 被引量:1
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作者 YUAN Jin-tao CHEN Wan-xu +1 位作者 ZENG Jie YE Xin-yue 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1824-1841,共18页
Cropland elevation uplift(CLEU) has recently become a new challenge for agricultural modernization,food security,and sustainable cropland use in China.Uncovering the rules of CLEU is of great theoretical and practical... Cropland elevation uplift(CLEU) has recently become a new challenge for agricultural modernization,food security,and sustainable cropland use in China.Uncovering the rules of CLEU is of great theoretical and practical significance for China’s sustainable agricultural development and rural revitalization strategy.However,existing studies lack in-depth disclosure of multi-scale CLEU evolution rules,making it difficult to support the formulation of specific cropland protection policies.We analyzed the spatio-temporal evolution and multiscale CLEU in China from 1980 to 2020 using the Lorenz curve,gravity center model,hotspot analysis,and cropland elevation spectrum.The results indicated that the center of gravity of cropland moved to the northeast from 1980 to 2000 and then shifted to the northwest.The spatial distribution of cropland became increasingly imbalanced from 1980 to 2000.The change hotspots clustered in the northwest and the northeast,whereas cold-spots were mainly in southeastern China.The average elevation of cropland increased by 17.38 m,and the elevation uplift rule in different regions differed evidently across scales.From 1980 to 2000,all provinces except Xinjiang,Inner Mongolia,Gansu,and Yunnan exhibited CLEU,with Qinghai,Tibet,Beijing,and Guangdong showing the most noticeable uplifting.The CLEU can alleviate the shortage of cropland to some extent.However,without a planning constraint,the CLEU will lead to the increase of ecological risk and food security risk. 展开更多
关键词 CROPLAND Elevation uplift rules MULTI-SCALE Elevation spectrum China
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Assessing the effects of long-term recreational activities on landscape changes in Abant Natural Park,Turkey
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作者 Gunay Gakir Haldun Miiderrisoglu Latif Giirkan Kaya 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期453-461,共9页
Natural, protected areas offer many possibili- ties for recreation in rural areas such as camping, one of the most popular activities. The system established for pro- tected areas in Turkey aims to provide a foundatio... Natural, protected areas offer many possibili- ties for recreation in rural areas such as camping, one of the most popular activities. The system established for pro- tected areas in Turkey aims to provide a foundation for conserving areas for recreation. One such area, Abant Natural Park, is convenient for visits from Turkey's two most populated metropolitan areas, Istanbul and Ankara. It also attracts tourists from other regions and countries. The aim of the present study was to evaluate the vegetation loss and land cover changes due to picnic/camping, transhu- mance, and construction over 40 years (1966-2004) in the park using data on visitor numbers, vegetation patches, corridors and connectivity. For evaluating landscape vari- ables, remote sensing data and aerial photos were used. When aerial photos were imported into the ERDAS Imagine program, ground control points identified, and individual images orthorectified, land degradation was not found in the use of camping areas. Moreover, manmade areas (road, car park and hotel) observably increased, thus decreasing the forest lands. The findings show that the land use types that have had the greatest ecological impact are transhumance and construction of hotels, which also require infrastructure development. The intensity of the ecological effects mandates precautions to lessen the impacts and the need for continuing assessment to ensure sustainable use of the area. 展开更多
关键词 Natural protected areas Remote sensing GIS FOREST LULC Abant Natural Park TURKEY
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Intermediate-scale Analysis of Landscape Characteristics Affecting Edge Formation in Burned Forests in Samcheok,Korea
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作者 Sang-Woo LEE Myoung-Soo WON +1 位作者 Joo-Mee LEE Hai-Gyoung KIM 《Journal of Mountain Science》 SCIE CSCD 2014年第2期384-397,共14页
Compared to burn interiors, edges exhibit distinct biotic and abiotic conditions that include microclimate, wind speed, sunlight levels, soil composition, moisture content, nutrient availability, population density, a... Compared to burn interiors, edges exhibit distinct biotic and abiotic conditions that include microclimate, wind speed, sunlight levels, soil composition, moisture content, nutrient availability, population density, and species diversity. This study characterized the landscapes in which burned forest edges formed in Samcheok, Korea. Over the study area, 500-m2 grid cells were generated to capture landscape characteristics. Grid cells intersecting burn boundary lines were designated as edge, while cells without these lines were classified as the interior of burned areas. Topographic variables including slope, elevation, topographic wetness index, solar radiation index, and proportions of fuel and land use types within grid cells were computed in a geographical information system(GIS). Correlation analysis with modified t-test and regression tree analysis were performed to explore the influences of landscape variables on edge formation with avoiding spatial autocorrelation problems. The results indicated that edges formed at low elevations with mild slopes, high topographic wetness, and low solar radiation. Edges were unlikely to form in areas dominated by Japanese red pines at low elevations. Moreover, heterogeneous land use/cover types contributed significantly to edge formation. Different forest management strategies for different landscape conditions can be more effective for enhancing resilience of forests to fire. Reducing susceptible fuel types might be effective at low elevations, while enhancing forest heterogeneity might be more effective at high elevations. 展开更多
关键词 景观特征 森林管理 尺度分析 韩国 土地利用类型 低海拔地区 土地利用 覆盖 火烧
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Exploration of nature-based biomimetic approach in landscape architectural design: parametric study of candelabra model design
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作者 Biljana S.Jović Anđela D.Mitić 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期278-288,共11页
This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower.The design process described in this research contains two step... This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower.The design process described in this research contains two steps:biological and geometrical.In the first biological step,a proper model for the creation of an urban element was found from nature in a Bell flower(Campanula persicifolia L.).The upper leaves of the selected plant,which are small with a linear spear and sharpening at the top,were chosen for the modeling process.The second step included applying two geometrical methods,i.e.,Voronoi diagrams and Delaunay triangulation.A geometrical leaf form of the selected plant species and the modeling process were obtained using aparametric modeling software,Blender.Using different Blender plug-ins and modifiers,Delaunay triangulation and Voronoi diagram were implemented by marking the starting points on the leaf form in the image data source,adjusting the Delaunay triangulation parameters,and creating Voronoi diagrams in which the Voronoi points were located at the shortest distance from the edges of the Voronoi polygon.Consequently,a three dimensional model of a candelabra was developed through this study. 展开更多
关键词 Biomimetic approach Landscape architectural design Parametric study Blender software Three dimensional model of candelabra
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Discussion on the Landscape Pattern Change of Watershed
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作者 ZHANG Jun - bin 《水土保持研究》 CSCD 北大核心 2006年第4期137-139,142,共4页
Evaluating the transition of landscape can understand that ecosystem processes are being influenced by disturbance.For this reason,it is essential that using appropriate mapping techniques and quantitative methods to ... Evaluating the transition of landscape can understand that ecosystem processes are being influenced by disturbance.For this reason,it is essential that using appropriate mapping techniques and quantitative methods to assess landscape condition within different disturbance regimes.Landscape metrics were calculated for segmented areas of homogeneous land use in watershed to allow understanding and characterization of ecosystem.Chen-yu-lan watershed,located in the central of Taiwan,is a sensitivity area for disaster such as earthquakes and typhoons.In this study we focus on how the natural disaster affect landscape pattern.The study shows that landscape metrics can measure the effect of typhoon and earthquake disturbance regime.The analysis shows that evaluating landscape transition can contribute more detailed information for managing ecosystem. 展开更多
关键词 土地利用 生态系统 生态环境 森林资源
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Selection and Configuration of Landscape Plants for the Median Strip of Suibei Highway
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作者 CUI Jian WANG Hongyi 《Journal of Landscape Research》 2017年第2期31-32,37,共3页
Landscape design and greening quality of the median strip on multi-lane highway are the most important parts of the visual impact factor. Using ornamental plants to create a comfortable greening scene on the median st... Landscape design and greening quality of the median strip on multi-lane highway are the most important parts of the visual impact factor. Using ornamental plants to create a comfortable greening scene on the median strip, can effectively prevent glare and improve the road driving environment. The paper studied and analysed the median strip greening status and the driving environment problems of Suibei highway in north China. On the basis of local environmental conditions, the research selected suitable landscape species to form well-proportioned landscape scenes for this highway median strip. Three sets of reference landscape configuration modes were designed for improving the median strip of Suibei highway based on the recommended landscaping plants in this paper. 展开更多
关键词 HIGHWAY Median Strip LANDSCAPE Ornamental plants North China
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Appreciation of Landscape Architecture in Chicago Millennium Park
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作者 LI Hongxing 《Journal of Landscape Research》 2015年第1期5-6,共2页
Chicago Millennium Park is a place where "post-modern architecture" concentrates, Cloud Gate, Crown Fountain and Jay Pritzker Music Pavilion are three representative post-modern architectures in the park. Mi... Chicago Millennium Park is a place where "post-modern architecture" concentrates, Cloud Gate, Crown Fountain and Jay Pritzker Music Pavilion are three representative post-modern architectures in the park. Millennium Park is an urban public space of Chicago City, its design concepts such as resource sharing and adaptation to local conditions are worth learning. 展开更多
关键词 Millennium Park Urban public space Post-modern architecture Public sculpture
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Landscape Planning and Design of Rural Health-caring Tourist Bases
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作者 CHEN Hua CHEN Ning +3 位作者 LIANG Rui XIAO Yanghong LIU Ruibing LIAO Weipeng 《Journal of Landscape Research》 2020年第4期33-35,40,共4页
With the further deepening of rural revitalization strategies,rural construction and development has been attracting increasing attention,on this basis rural health-caring tourism has developed.This research,by follow... With the further deepening of rural revitalization strategies,rural construction and development has been attracting increasing attention,on this basis rural health-caring tourism has developed.This research,by following ecological and human-centered principles,adopted the renovation planning of Dacun Village,Fengcun Town in Deqing County,Zhaoqing City,tried to build Dacun Village into a rural healthcaring base that integrates the functions of serving for the aged,recreation,living,health care,tourism and vacation,and provided a new development mode uniting health care with rural tourism. 展开更多
关键词 Health-caring tourism Rural revitalization Rural landscape Landscape planning
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Study on Photosynthetic Characteristics of Hybrid Mulberry in Autumn under Herbaceous Cultivation
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作者 Fangying XU Jinjian YU +2 位作者 Huaqiang DONG Dezhong CHEN Jianzhong TAN 《Agricultural Biotechnology》 CAS 2023年第5期19-21,25,共4页
[Objectives]This study was conducted to clarify the physiological mechanism of growth of hybrid mulberry after autumn cutting in herbaceous cultivation.[Methods]The net photosynthetic rate(Pn),stomatal conductance(Gs)... [Objectives]This study was conducted to clarify the physiological mechanism of growth of hybrid mulberry after autumn cutting in herbaceous cultivation.[Methods]The net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular CO_(2) concentration(Ci)and transpiration rate(Tr)of leaves were measured under different treatment conditions using a Li-6400XT portable photosynthetic measurement system.[Results]After harvest of mulberry shoots in autumn,leaf Pn decreased with the extension of branch and leaf growth time,while Gs,Ci and Tr showed a trend of first increasing and then decreasing.The Pn was affected by factors such as leaf positions,mulberry varieties,cutting,and fertilization,which was manifested by the 6 th to 10 th mature leaves>the 2 nd to 4 th tender leaves,‘Nongsang 14’>hybrid mulberry,intermediate cut>uncut,and normal fertilization>no fertilization,all showing significant differences(P<0.05).Combined with the results of Gs,Ci and Tr measurements,it was found that the changes in leaf Pn were mainly related to non-stomatal factors.Timely cutting and harvesting during summer and autumn could significantly improve the photosynthetic rate of mulberry leaf,which was beneficial for extending the late autumn growth period of hybrid mulberry under herbaceous cultivation.[Conclusions]This study provides a theoretical reference for mulberry shoot harvesting techniques in summer and autumn. 展开更多
关键词 Hybrid mulberry Herbaceous cultivation Harvest of mulberry shoots Photosynthetic rate Leaf age
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Associative cultural landscape approach to interpreting traditional ecological wisdom:A case of Inuit habitat
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作者 Peng Zhang Shuai Li 《Frontiers of Architectural Research》 CSCD 2024年第1期79-96,共18页
Global climate change and the accelerated melting of glaciers have raised concerns about the ability to manage ice-snow environments.Historically,human ancestors have mastered the ecological wisdom of working with ice... Global climate change and the accelerated melting of glaciers have raised concerns about the ability to manage ice-snow environments.Historically,human ancestors have mastered the ecological wisdom of working with ice-snow environments,but the phenomenon has not yet been articulated in cultural landscape methodologies that emphasize“nature-culture relevance”.The challenging living environment often compels indigenous people to form a strong bond with their surroundings,leading to the creation of long-term ecological wisdom through synergistic relationships with the environment.This ecological environment is conceptualized as a cognitive space in the form of the landscape,with which the aboriginal community norms and individual spirits continually interact.Such interactions generate numerous non-material cultural evidences,such as culture,art,religion,and other ideological aspects of the nation.These evidences symbolize the intellectual outcome of the relationship between humans and the landscape,and they create the“spiritual relevance”through personification and contextualization.The aim of the study is to explore the traditional ecological wisdom of the Inuit people who live in the harsh Arctic,and analyze the Inuit’s interaction with the landscape through the lens of“associative cultural landscape”,and decode the survival experience that the Inuit have accumulated through their long-term synergy with the Arctic environment.The findings focus on the synergy between the Inuit and the ice-snow landscape,examining the knowledge and ecological wisdom that the Inuit acquire from the ice-snow landscape.Our goal is to develop a perspective of the ecological environment from the viewpoint of aboriginal people and establish a methodology,model,and framework for“associative cultural landscape”that incorporates ethnic non-material cultural evidences.From the results,a total of nine models for interpreting traditional Inuit ecological wisdom are generated based on the“diamond model”of“associative cultural landscape”,covering the transition from the physical landscape to a spiritual one and demonstrating the associative role of the landscape in stimulating potential spiritual cognitive abilities in humans. 展开更多
关键词 Landscape architecture Associative cultural landscape Nature-culture relevance Cultural landscape Traditional ecological wisdom Non-material cultural evidence Methodology HABITAT Living environment Ice-snow landscape
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Comparative Study on Spatial Forms of Ancient Waterside Towns Based on Google Earth Pro-Taking the Example of Qingmuchuan,Fenghuang and Houliu in Southern Shaanxi,China 被引量:5
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作者 Mei Yang Zhaoyang Feng 《Journal of Environmental Science and Engineering(B)》 2020年第1期12-22,共11页
The purpose of this study is to address the problem of ancient towns dying out in developing countries,particularly China.Intensifying conflicts between human settlements and the natural environment are described,and ... The purpose of this study is to address the problem of ancient towns dying out in developing countries,particularly China.Intensifying conflicts between human settlements and the natural environment are described,and guidelines are proposed for the development of waterside ancient towns in China’s southern Shaanxi Province in the interest of conserving cultural and natural heritage.The towns of Qingmuchuan,Fenghuang and Houliu were selected as representative examples due to their strong reputation among tourists.They have the characteristics of traditional southern Shaanxi towns,but each has a completely different layout,space and structure.The comparative findings of this research provide a point of reference for establishing guidelines to preserve the integrity of ancient towns worldwide.In this paper,we compare the geographical conditions with the layout and texture of the streets by Google Earth Pro.And we analyze the details of spaces along the river zones,architectural styles and building decorations in order to research the relationship between the natural environment and the human settlement conditions.We note the unfortunate common trend of commercial development steadily taking over the natural environment,particularly the rivers and unique elements of the old towns.Finally,we summarize the similarities and differences of the spatial forms among these towns and put forward proposals for the further development of ancient towns.This research is important for all regions which stand to lose their national treasures.Consequently,measures should be to taken to curtail hyper development before we lose our historicscenery. 展开更多
关键词 Google Earth PRO waterside ANCIENT TOWNS comparative study on spatial forms Qingmuchuan Fenghuang Houliu
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Mechanical properties of cocoons constructed consecutively by a single silkworm caterpillar,Bombyx mori 被引量:3
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作者 S.Q.Huang H.P.Zhao +3 位作者 X.Q.Feng W.Cui Z.Lin M.Q.Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第2期151-160,共10页
Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons ... Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons. 展开更多
关键词 SILK Silkworm cocoon Mechanical property Biomimetics
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Research on Ecological Water Cycle and Purification in Rural Landscape——Take Zhangjia Village Ecological Wastewater Treatment Project in Henan Province as an Example 被引量:5
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作者 Mengmeng Li Mei Yang +1 位作者 Min Zhang Tao Xu 《Journal of Environmental Science and Engineering(A)》 2020年第5期188-203,共16页
Rural landscape is not only a natural landscape,but also a cultural landscape.The improvement of rural environment in Lushi County is carried out under the background of“Building Beautiful Villages”.Through the plan... Rural landscape is not only a natural landscape,but also a cultural landscape.The improvement of rural environment in Lushi County is carried out under the background of“Building Beautiful Villages”.Through the plan of environmental improvement,the appearance of villages in rural areas will be significantly improved,and the gap between urban and rural areas will be shortened.This research addresses the problems of scarce water resources,imperfect rainwater collection facilities,and increased environmental pollution in rural areas,and explores a flexible,effective,and integrated landscape ecological water treatment system that integrates with natural ecosystems.The practice has shown that the flexible combination of different technical measures according to local conditions and the construction of ecological water self-circulation and self-purification systems can reduce maintenance costs and achieve sustainable landscape.The virtuous cycle of the revetment’s micro-ecology greatly improves the environmental carrying capacity of the landscape.Reasonable water management system is more flexible in dealing with unexpected problems.The thesis proposes landscape design strategies for water circulation and water purification in rural areas,and applies them to actual design cases.It attempts to introduce a combined treatment system to achieve a more diverse landscape concept and further explore the healthy and sustainable development of rural water environment. 展开更多
关键词 Landscape water ecological water cycle ecological water purification Zhangjia Village Henan Province
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Effect of altitude and climatic parameters on shrub-meadow community composition and diversity in the dry valley region of the eastern Hengduan Mountains,China 被引量:2
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作者 ZONG Hua SUN Jia-rui +2 位作者 ZHOU Lu BAO Fang ZHENG Xian-zhu 《Journal of Mountain Science》 SCIE CSCD 2022年第4期1139-1155,共17页
Because of the“foehn effect”,deeply incised gorges of major rivers in the Hengduan Mountains(commonly called dry valleys)have semiarid or arid climate.Harsh environment and difficult access have so far obstructed th... Because of the“foehn effect”,deeply incised gorges of major rivers in the Hengduan Mountains(commonly called dry valleys)have semiarid or arid climate.Harsh environment and difficult access have so far obstructed the systematic inventory and documentation of the flora of these dry valleys.This is particularly problematic for efforts towards the conservation of endemic and valuable plant species.Therefore,102 shrub-meadow community survey plots were set up along four dry valleys in Ganzi prefecture,located in the eastern Hengduan Mountains,China.The compositions,richness,diversity of these communities were calculated and assessed using sample plot survey and phytosociological approach.Overall,244 plant species were recorded,consisting of subtropical(48.77%)and temperate(38.83%)species,47.13%of which were endemic to southwest China.Obvious differences in species composition and structure along the altitude gradient were observed.The variations of richness,diversity,and evenness followed a bimodal-hump shaped pattern with increasing altitude,with peak occurring at mid-level altitude(3501–4000 m)and valley occurring at 2501–3000 m altitude.The regions at 2501–3000 m altitudes were more sensitive to global climate change and biological interference,and were found to have the highest protection value.The impacts of altitude gradients and climatic parameters on the features of this shrubmeadow community were also evaluated using principal component and multiple linear stepwise regression analysis methods.Altitude and temperature-related variables were the most important drivers of both species richness and cover.Speciesα-diversity here only depended on the precipitation frequency.This founding could help to understand the impact of the very harsh environment and altitude gradient on plant-plant interactions in a variety of natural systems. 展开更多
关键词 Dry valley Shrub meadow community Composition DIVERSITY ALTITUDE Climatic parameters
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The Conservation Status and Conservation Strategy of Picea neoveitchii 被引量:3
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作者 Zhang Deshun Kim Yongshik +1 位作者 Mike Maunder Li Xiufen 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第3期58-64,共7页
Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the rel... Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites. The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon’s phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations. Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research. 展开更多
关键词 守恒 状况 地方物种 生态系统
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Flower Development and Anatomy of Agapanthus praecox ssp. orientalis (Leighton) Leighton 被引量:3
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作者 ZHANG Di SHEN Xiao-hui ZHUO Li-huan 《Agricultural Sciences in China》 CAS CSCD 2011年第9期1365-1373,共9页
Floral buds of Agapanthus praecox ssp. orientalis were observed under dissecting and optical microscope to characterize floral organs development and to study relationships between anther development and microsporogen... Floral buds of Agapanthus praecox ssp. orientalis were observed under dissecting and optical microscope to characterize floral organs development and to study relationships between anther development and microsporogenesis. Floral organs differentiation was comprised of 6 distinct stages including nought differentiation, inflorescence bud differentiation, floret primordia differentiation, tepal primordia differentiation, stamen primordia differentiation, and pistil primordia differentiation. Six tepals differentiated almost simultaneously which cross arranged in space and appeared in hexagonal distribution pattern. Six stamens were differentiated inside the tepals at the same time. Finally, 3 carpel primordia differentiated and formed syncarpous pistil. The whole process of floral bud differentiation took approximately 40 d with the first 3 stages developing more slowly than the later 3 stages. Morphology and color of the anther underwent obvious changes during the period between stamen primordia differentiation and anther maturation. Microspores also underwent significant development during this same interval. The relationship between the process of microsporogenesis and anther development has already been made clear by the sauash techniaue. 展开更多
关键词 Agapanthus praecox ssp. orientalis floral organs floral bud differentiation MICROSPOROGENESIS
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Rank-size Distributions of Chinese Cities: Macro and Micro Patterns 被引量:1
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作者 LI Shujuan 《Chinese Geographical Science》 SCIE CSCD 2016年第5期577-588,共12页
A large number of studies have been conducted to find a better fit for city rank-size distributions in different countries. Many theoretical curves have been proposed, but no consensus has been reached. This study arg... A large number of studies have been conducted to find a better fit for city rank-size distributions in different countries. Many theoretical curves have been proposed, but no consensus has been reached. This study argues for the importance of examining city rank-size distribution across different city size scales. In addition to focusing on macro patterns, this study examines the micro patterns of city rank-size distributions in China. A moving window method is developed to detect rank-size distributions of cities in different sizes incrementally. The results show that micro patterns of the actual city rank-size distributions in China are much more complex than those suggested by the three theoretical distributions examined(Pareto, quadratic, and q-exponential distributions). City size distributions present persistent discontinuities. Large cities are more evenly distributed than small cities and than that predicted by Zipf′s law. In addition, the trend is becoming more pronounced over time. Medium-sized cities became evenly distributed first and then unevenly distributed thereafter. The rank-size distributions of small cities are relatively consistent. While the three theoretical distributions examined in this study all have the ability to detect the overall dynamics of city rank-size distributions, the actual macro distribution may be composed of a combination of the three theoretical distributions. 展开更多
关键词 城市规模分布 中国城市 宏观模式 微观形态 不均匀分布 大小分布 城市等级 理论分布
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