[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
Double diffusion convection in a cavity with a hot square obstacle inside is simulated using the lattice Boltzmann method. The results are presented for the Rayleigh numbers 104,105 and 106, the Lewis numbers 0.1, 2 a...Double diffusion convection in a cavity with a hot square obstacle inside is simulated using the lattice Boltzmann method. The results are presented for the Rayleigh numbers 104,105 and 106, the Lewis numbers 0.1, 2 and 10 and aspect ratio A(obstacle height/cavity height) of 0.2, 0.4 and 0.6 for a range of buoyancy number N = 0 to- 4 with the effect of opposing flow. The results indicate that for |N| b 1, the Nusselt and Sherwood numbers decrease as buoyancy ratio increases, while for |N| N 1, they increase with |N|. As the Lewis number increases, higher buoyancy ratio is required to overcome the thermal effects and the minimum value of the Nusselt and Sherwood numbers occur at higher buoyancy ratios. The increase in the Rayleigh or Lewis number results in the formation of the multi-cell flow in the enclosure and the vortices will vanish as |N| increases.展开更多
The spatial and temporal changes of landscape pattern and their driving forces in each functional zone of Nanling National Nature Reserve were analyzed based on the GIS and RS platform. The results showed that from 19...The spatial and temporal changes of landscape pattern and their driving forces in each functional zone of Nanling National Nature Reserve were analyzed based on the GIS and RS platform. The results showed that from 1988 to 2009, in respect of changes of Jandscape area, the main forest landscape accounted about 95% of the total area, of which evergreen broad-leaved forest had the largest area, accounting for more than 50% of the total area. The dominant landscape was coniferous forest. In respect of landscape fragmentation, the density index of land- scape in the whole area increased, and the degree of landscape fragmentation also increased. In the core area, the patch density decreased slightly, and the average patch area of each type of landscape increased; the degree of landscape fragmen- tation increased slightly. In the buffer area and the experimental area, the degree of landscape fragmentation increased. In terms of landscape diversity, the landscape pattern in the whole area became complex, and the diversity index of landscape in- creased and the degree of heterogeneity increased. In the core area, the diversity index of landscape increased slightly. In the buffer area, it increased significantly. In the experiment area, the diversity index reduced, and the degree of landscape het- erogeneity reduced. In the whole study area, the landscape tended to be diversified. The landscape pattern of the experimental area was consistent with that of the whole study area, and there was no obvious change in the buffer zone, while the landscape pattern in the core area developed towards the single direction.展开更多
Landscape ecology provides new theoretical frameworks and methodologies for understanding complex ecological phenomena at multiple scales.Studies of landscape ecology focus on understanding the dynamics of eco-logical...Landscape ecology provides new theoretical frameworks and methodologies for understanding complex ecological phenomena at multiple scales.Studies of landscape ecology focus on understanding the dynamics of eco-logical patterns and processes,and highlight the integration of multiple disciplines.In this paper,we discussed the problems and challenges that landscape ecology is currently facing,emphasizing the limitations of current methods used to describe dynamic landscape patterns and processes.We suggested that the focus should be on the integration of ground-based observation,mobile monitoring,transect survey,and remote-sensing monitoring,as well as improved coupling of experimental and model simulations.In addition,we outlined the research frontiers in landscape ecology,including scaling,integrated pattern and process modeling,and regional synthesis.Lastly,a brief review of pat-tern-process-scale coupling studies in China was provided.We concluded by pointing out that pattern-process-scale interactions,correlations between natural,economic,and social processes,and the coupling of human and natural systems will be major research areas in landscape ecology in the future.展开更多
The incredible extent of current environmental destruction justifies the modern concern to resist the alienated view of nature as a resource to exploit a totality of dead and meaningless objects, a totally disenchante...The incredible extent of current environmental destruction justifies the modern concern to resist the alienated view of nature as a resource to exploit a totality of dead and meaningless objects, a totally disenchanted world. In this spirit, modern philosophy tries to take nature seriously by recapturing a sense of nature＇s intrinsic value. Hegel respects nature to the extent that it bears the trace of the human mind, to the extent that it is forced ＂to speak the voice of reason.＂ Although there are grounds for being critical of the Hegelian project, especially because Hegel remains silent on the issue of our duties towards nature for the sake of nature and his argumentation serves the primordial desires of human reasoning and not the rights of nature itself, it is suggested that no matter how much inauthentic and incomplete is the recognition that the human mind acquires in its dialectical confrontations with nature. Hegelian phenomenology grants the human mind with a remarkable degree of self-certainty, necessary for all its subsequent educational enterprises.展开更多
In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,...In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,the partial differential equations of the one-dimensional heat conduction in the pavement were established on the basis of the heat transfer theory.Furthermore,the function forms of the initial and boundary conditions of the equations were created through the field experiments.The general solution of the pavement one-dimensional heat conduction partial differential equations was acquired by using Green's function,and the explicit expression of pavement temperature field under specific constraint conditions was derived.For the purpose of analysis,the pavement temperatures in different seasons were calculated using the explicit expression of pavement temperature field,and the calculation accuracy was analyzed through the comparison between measured and calculated values.Then,the relationship between fitting accuracy and calculation accuracy of pavement temperatures was analyzed.The analysis results show that: the usage of "Environment-Surface" system simplifies the calculation of pavement temperature field; the relative error between calculated and measured values is generally less than 7% and is seldom influenced by seasons; there is a positive correlation between the calculation accuracy and the fitting accuracy of pavement surface temperature; high fitting accuracy would result in less error of pavement temperature prediction.展开更多
Marx and Engles believed that man and nature develop harmoniously, when the activities of man constitute the content of nature, which is changed constantly because of the activities of man. Marx and Engles also pointe...Marx and Engles believed that man and nature develop harmoniously, when the activities of man constitute the content of nature, which is changed constantly because of the activities of man. Marx and Engles also pointed out the duality of the conquest, change and influence exerted on nature by man. On one hand, it can improve people’s living conditions and make people free from the enslavement of the nature. On the other hand, it may also lead to excessively snatching and wrecking nature, then make the deterioration of the environment and ecology out of balance. They also, from the technical angle of ecology, put forward the concrete measures to realize the harmonious symbiosis of man and nature in the development of economy. They also believed that only when socialism or communism is realized, can the conciliation of mankind and nature be realized finally. Marx and Engle’s theory of harmonious symbiosis of man and nature is of great theoretical directive significance for us to insist on the scientific development view.展开更多
Understanding an utterance is far from proposition analysis and literal meaning interpretation. It is the unity of what is said and what is implicated. Grice＇s theory of conversational implicature provides some expli...Understanding an utterance is far from proposition analysis and literal meaning interpretation. It is the unity of what is said and what is implicated. Grice＇s theory of conversational implicature provides some explicit account of how it is possible to mean more than what is literally expressed by the conventional sense of the linguistic expressions uttered. Using this theory, we can infer the speaker＇s real attention, appreciate figure of speech in literary work, and improve our communicative competence.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Double diffusion convection in a cavity with a hot square obstacle inside is simulated using the lattice Boltzmann method. The results are presented for the Rayleigh numbers 104,105 and 106, the Lewis numbers 0.1, 2 and 10 and aspect ratio A(obstacle height/cavity height) of 0.2, 0.4 and 0.6 for a range of buoyancy number N = 0 to- 4 with the effect of opposing flow. The results indicate that for |N| b 1, the Nusselt and Sherwood numbers decrease as buoyancy ratio increases, while for |N| N 1, they increase with |N|. As the Lewis number increases, higher buoyancy ratio is required to overcome the thermal effects and the minimum value of the Nusselt and Sherwood numbers occur at higher buoyancy ratios. The increase in the Rayleigh or Lewis number results in the formation of the multi-cell flow in the enclosure and the vortices will vanish as |N| increases.
文摘The spatial and temporal changes of landscape pattern and their driving forces in each functional zone of Nanling National Nature Reserve were analyzed based on the GIS and RS platform. The results showed that from 1988 to 2009, in respect of changes of Jandscape area, the main forest landscape accounted about 95% of the total area, of which evergreen broad-leaved forest had the largest area, accounting for more than 50% of the total area. The dominant landscape was coniferous forest. In respect of landscape fragmentation, the density index of land- scape in the whole area increased, and the degree of landscape fragmentation also increased. In the core area, the patch density decreased slightly, and the average patch area of each type of landscape increased; the degree of landscape fragmen- tation increased slightly. In the buffer area and the experimental area, the degree of landscape fragmentation increased. In terms of landscape diversity, the landscape pattern in the whole area became complex, and the diversity index of landscape in- creased and the degree of heterogeneity increased. In the core area, the diversity index of landscape increased slightly. In the buffer area, it increased significantly. In the experiment area, the diversity index reduced, and the degree of landscape het- erogeneity reduced. In the whole study area, the landscape tended to be diversified. The landscape pattern of the experimental area was consistent with that of the whole study area, and there was no obvious change in the buffer zone, while the landscape pattern in the core area developed towards the single direction.
基金Under the auspices of National Natural Science Foundation of China (No.40930528)State Forestry Administration of China (No.201004058)
文摘Landscape ecology provides new theoretical frameworks and methodologies for understanding complex ecological phenomena at multiple scales.Studies of landscape ecology focus on understanding the dynamics of eco-logical patterns and processes,and highlight the integration of multiple disciplines.In this paper,we discussed the problems and challenges that landscape ecology is currently facing,emphasizing the limitations of current methods used to describe dynamic landscape patterns and processes.We suggested that the focus should be on the integration of ground-based observation,mobile monitoring,transect survey,and remote-sensing monitoring,as well as improved coupling of experimental and model simulations.In addition,we outlined the research frontiers in landscape ecology,including scaling,integrated pattern and process modeling,and regional synthesis.Lastly,a brief review of pat-tern-process-scale coupling studies in China was provided.We concluded by pointing out that pattern-process-scale interactions,correlations between natural,economic,and social processes,and the coupling of human and natural systems will be major research areas in landscape ecology in the future.
文摘The incredible extent of current environmental destruction justifies the modern concern to resist the alienated view of nature as a resource to exploit a totality of dead and meaningless objects, a totally disenchanted world. In this spirit, modern philosophy tries to take nature seriously by recapturing a sense of nature＇s intrinsic value. Hegel respects nature to the extent that it bears the trace of the human mind, to the extent that it is forced ＂to speak the voice of reason.＂ Although there are grounds for being critical of the Hegelian project, especially because Hegel remains silent on the issue of our duties towards nature for the sake of nature and his argumentation serves the primordial desires of human reasoning and not the rights of nature itself, it is suggested that no matter how much inauthentic and incomplete is the recognition that the human mind acquires in its dialectical confrontations with nature. Hegelian phenomenology grants the human mind with a remarkable degree of self-certainty, necessary for all its subsequent educational enterprises.
基金Projects(2012zzts019,2012QNZT048)supported by the Fundamental Research Funds for the Central Universities of Central South University,ChinaProject(201306370121)supported by the State Scholarship Fund of China+3 种基金Project(JT20090898002)supported by Traffic Technology Fund of Hainan Province,ChinaProject(2012M521563)supported by the China Postdoctoral Science FoundationProject(51248006)supported by The National Natural Science Foundation of ChinaProject(511114)supported by the Natural Science Foundation of Hainan Province,China
文摘In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,the partial differential equations of the one-dimensional heat conduction in the pavement were established on the basis of the heat transfer theory.Furthermore,the function forms of the initial and boundary conditions of the equations were created through the field experiments.The general solution of the pavement one-dimensional heat conduction partial differential equations was acquired by using Green's function,and the explicit expression of pavement temperature field under specific constraint conditions was derived.For the purpose of analysis,the pavement temperatures in different seasons were calculated using the explicit expression of pavement temperature field,and the calculation accuracy was analyzed through the comparison between measured and calculated values.Then,the relationship between fitting accuracy and calculation accuracy of pavement temperatures was analyzed.The analysis results show that: the usage of "Environment-Surface" system simplifies the calculation of pavement temperature field; the relative error between calculated and measured values is generally less than 7% and is seldom influenced by seasons; there is a positive correlation between the calculation accuracy and the fitting accuracy of pavement surface temperature; high fitting accuracy would result in less error of pavement temperature prediction.
文摘Marx and Engles believed that man and nature develop harmoniously, when the activities of man constitute the content of nature, which is changed constantly because of the activities of man. Marx and Engles also pointed out the duality of the conquest, change and influence exerted on nature by man. On one hand, it can improve people’s living conditions and make people free from the enslavement of the nature. On the other hand, it may also lead to excessively snatching and wrecking nature, then make the deterioration of the environment and ecology out of balance. They also, from the technical angle of ecology, put forward the concrete measures to realize the harmonious symbiosis of man and nature in the development of economy. They also believed that only when socialism or communism is realized, can the conciliation of mankind and nature be realized finally. Marx and Engle’s theory of harmonious symbiosis of man and nature is of great theoretical directive significance for us to insist on the scientific development view.
文摘Understanding an utterance is far from proposition analysis and literal meaning interpretation. It is the unity of what is said and what is implicated. Grice＇s theory of conversational implicature provides some explicit account of how it is possible to mean more than what is literally expressed by the conventional sense of the linguistic expressions uttered. Using this theory, we can infer the speaker＇s real attention, appreciate figure of speech in literary work, and improve our communicative competence.
