To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable l...To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable land development. In this research, we constructed an evaluation framework of multiple land-use functions(LUFs) based on sustainable land-use theory. Specifically,, we classified the multiple LUFs into three types: agricultural production function(APF), living function(LVF), and ecological service function(ESF).We then spatialized the economic and social data, and implemented the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs) model and RUSLE(Revised Universal Soil Loss Equation) model to evaluate each sub-LUF(crop production, aquatic production, woodlands production, livestock production, living space, life quality, water supply, soil conservation, climate regulation, biological conservation) in central China in 2000 and again in 2015. Moreover, by analyzing the changes to LUFs and the relationships between each LUF change, we were able to discern patterns of LUF change in central China. The results show that: (1)42.12% of total territory in the study area increased their APF from 2000 to 2015, while 43.41% of the lands increased their ESF yet only 8.98% of the lands increased their LVF;(2) in Hubei and Hunan, there was more land with an increase of APF than in Anhui or Jiangxi. The APF in Jiangxi exhibited the greatest decline over time period, the LVF increased more in the provincial capital cities than in other regions, and the ESF expanded more in Jiangxi than in the other provinces;and (3) the changes in APF were significantly and positively correlated with changes in LVF. Additionally, changes in ESF were negatively but non-significantly correlated with changes in APF and LVF.展开更多
The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory space.This manuscript analyzed and quantified the...The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory space.This manuscript analyzed and quantified the impact of EFPZ on the regional water conservation function,based on land use data from 2005,2008,2010,2015 and 2020,by conducting a counterfactual simulation along with the GeoSOS-FLUS model and the InVEST model.The results demonstrate that the delineation of EFPZ can significantly influence the water conservation.(1)From 2010 to 2020,as the EFPZ was implemented,the water conservation in the study area was increasing year by year,with a growth rate of 0.03×10^(8) m^(3)∙a^(-1).On the other hand,the simulated water conservation capacity without the implementation of EFPZ decreased year by year,with a decrease rate of 0.01×10^(8) m^(3)∙a^(-1).(2)The EFPZ accounts for only 23%of the total area,but the contribution rate of water conservation reaches 80%.The actual values of water conservation and average water yield per unit pixel in the EFPZ show an increasing trend both internally and externally,while the counterfactual simulation values exhibit a decreasing trend.(3)The water conservation is much higher within the EFPZ than without EFPZ.The implementation of EFPZ has a significant effect on the improvement of the water conservation capacity in Maqu EFPZ and Yellow River Source EFPZ.The protection effectiveness should be enhanced in Qilian Mountain EFPZ and afforestation activities need to be carefully considered in Loess Plateau EFPZ.展开更多
Functional zoning is a critical phase in the planning of parks.Through summarizing and analyzing the functional zoning modes of different urban park types in China,as well as comparing to the functional zoning modes o...Functional zoning is a critical phase in the planning of parks.Through summarizing and analyzing the functional zoning modes of different urban park types in China,as well as comparing to the functional zoning modes of nature reserves,famous scenic areas and overseas national parks,the functional zoning modes of urban wetland parks in China were elaborated in this study,the assumption of further sectorization were put forward,and theoretical supports were sought for more scientific and operable functional zoning of urban wetland parks.展开更多
The evaluation of marine function zoning (hereinafter referred to as MFZ) is an important part of MFZ. This paper studies the principles of MFZ evaluation and the evaluation procedures. It is proposed that three mai...The evaluation of marine function zoning (hereinafter referred to as MFZ) is an important part of MFZ. This paper studies the principles of MFZ evaluation and the evaluation procedures. It is proposed that three main aspects, including the evaluation of MFZ implementation situation, the evaluation of the performance effects and the evaluation of the changes of dependent conditions, are the top priorities in establishing an evaluation indicator system framework. The evaluation of MFZ implementation situation includes assessing the general situation of MFZ and the degree of implementation and public participation. The evaluation of the performance effects involves the assessments of the achievements and the existing problems in the rectification and standardization of utilizing the sea areas, protecting marine resources and environment, and promoting marine economic development. The evaluation of the changes of dependent conditions includes the assessments and measurements of the changes in the social and economic conditions, the use demands of marine industries, marine resource conditions and marine environmental conditions. This paper provides the means of integrating quantitative and qualitative approaches into the scientific and systematic evaluation on MFZ. The evaluation results can determine whether MFZ needs to be altered or not. The results also provide an important reference basis for determining whether a slight or great alteration is justified. To illustrate the utility of the MFZ evaluation indicator system, an evaluation example is given. Further studies are needed to make the evaluation of MFZ more scientific, reasonable, fair and effective.展开更多
An earthquake in the Jiuzhaigou area caused numerous secondary disasters, such as rolling stones, land collapse, landslides and debris flow, which badly affected the safety of human settlements and influenced the spat...An earthquake in the Jiuzhaigou area caused numerous secondary disasters, such as rolling stones, land collapse, landslides and debris flow, which badly affected the safety of human settlements and influenced the spatial layout of the post-disaster reconstruction. Therefore, carrying out assessments of land and identifying a suitable zone for human habitats were very important. This research creates the territorial suitability assessment and function zoning conceptual model in the earthquake-stricken area, and the new methods of the territorial suitability evaluation system were used to divide the spatial functional zones of the earthquake stricken area, which provide a theoretical guidance and decisionmaking basis for the reconstruction of the disaster area. The results showed that:(1) The Jiuzhaigou earthquake-stricken area comprises of an ecological area that has a high level of importance to the ecosystem. In the earthquake-stricken area, 65% of national land is at an altitude of 3000-4000 m, and therefore not suitable for a high level of intensive reconstruction, but reconstructed in an eco-friendly manner.(2) The zone suitable for reconstruction comprises mainly of the river valley and the flat terrain of western parts. The land with low suitability is mainly located on steep terrain, such as highmountains and low gullies. The geographic and geomorphic conditions limit the spread of a suitable reconstruction zone.(3) The earthquake-stricken area mainly comprises of a tourism industry gathering area, population gathering area, agriculture and animal husbandry development area, and ecological preservation area with areas of 76 km^2, 44 km^2, 1591 km^2 and 7512 km^2, respectively. Scientifically zoning the reconstruction areas using scientific evaluation may provide guidance for the location of reconstruction sites.展开更多
Ecological shelter zones reconstruction is an ecosystem restoration and conservation project aimed to the ecological safety of nations, regions and basins. Reconstruction of ecological shelter zones of the upper reach...Ecological shelter zones reconstruction is an ecosystem restoration and conservation project aimed to the ecological safety of nations, regions and basins. Reconstruction of ecological shelter zones of the upper reaches of the Yangtze River became one of the most important tasks of Western Development strategy. This article, taking Zhaotong as an example, studies the functional regionalization of ecological shelter zones. The study supplies a case for functional regionalization of small and medium regions whose main tasks are environment reservation. With the guidance of theories of functional regionalization, and based on the analysis of Zhaotong's natural, ecological and socioeconomic factors, the paper suggests five principles for factors selection. These principles include: (1) reversing order evaluation; (2) selecting main factors; (3) keeping the integrality of administrative regions of towns; and (4) making the products acceptable by local government. To analyze spatial status of selected factors, LUCC data in 2002, 1:50,000 relief maps and town-unit socioeconomic statistical data in 2004 are used. RS and GIS tools are also applied to melt traditional and modern geographical methods. This would be useful to functional regionalization research in mountainous areas. As a conclusion, the leading functional regions of ecological conservation or economic development are suggested, respectively. Zhaotong city is divided into two-level functional regions. The first-level includes three leading functional regions and they will lead developing direction of sub-regions. The second-level includes eight sub-regions, which are policy implemented regions, and will supply guidance to Zhaotong's ecological shelter zones reconstruction.展开更多
Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article anal...Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented.展开更多
Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divide...Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divided scientifically to clear its direction of development and protection. Therefore, based on ecological constraints, a beneficial discussion would be about the key ecological function areas adopting the concept of ecological protection restriction and supporting socioeconomic development for spatial function zoning. In this paper, the researchers, taking Tacheng Basin, Xinjiang of China as an example, choose township as basic research unit and set up an evaluation index system from three aspects, namely, ecological protection suitability, agricultural production suitability, and urban development suitability, which are analyzed by using spatial analysis functions and exclusive matrix method. The results showed that: 1) This paper formed a set of multilevel evaluation index systems for three types of spatial function zoning of the key ecological function areas based on a novel perspective by scientifically dividing Tacheng Basin into ecological space, agricultural space, and urban space,which realized the integration and scientific orientation for spatial function at the township scale. 2) Under the guidance of three types of spatial pattern, the functional orientation and suggestions of development and protection was clearly defined for ecological protection zones,ecological economic zones, agricultural production zones, and urban development zones. 3) A new idea of space governance is provided to promote the coordinated and sustainable development between ecology and economy, which can break the traditional mode of thinking about regional economic development, and offers a scientific basis and reference for macro decision-making.展开更多
Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of...Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of north central China. In this study, the desertified land was classified into five degrees: potential, light, medium, severe and extreme. The results indicate that the extent of desertification expands slightly, while desertification degree is enhanced significantly. About 22.35% of the total land area in the study area is in the desertification course, and the expanded area of both severely and extremely desertified land accounts for 3.67% of the total area of Mu Us Sandy Land. About 9053 klTl2 of area witnessed changes in land-use types between 1985 and 2000, which accounted for 10.75% of the total. More importantly, the area of conversions among cultivated land, forestland and rangeland added up to 971.6 km^2. This research reveals that both improper land-use types and conversions could accelerate the desertification process. Both cultivated land and forestland have more effects on the desertification development than rangeland. Some land-use type conversions, such as rangeland to cultivated land, rangeland to forestland and forestland to cultivated land, are attributed to the acceleration of the desertification development while the opposite can control the desertification development.展开更多
Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat (Triticum aestinum L...Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat (Triticum aestinum L.), maize (Zea mays L.) and sunflower (Helianthus annuus L.), growing in 76 farm fields are evaluated with modified discount function. Salinity ecological zones appropriate for these local crops are characterized and a case study is presented for crop salinity ecological zoning. The results show that the yield reductions of wheat, maize and sunflower when grown in saline soils are attributed primarily to a reduction in spikelet number, 1 000-grain weight and seed number per head, respectively. Sunflower is the most tolerant crop among the three which had a salinity tolerance index (ST-index) of 12.24, followed by spring maize and spring wheat with ST-Indices of 9.00 and 7.43, respectively. According to the crop salinity tolerance results, the arable land in the Heping Village of this district was subdivided into four salinity ecological zones: the most suitable, suitable, sub-suitable and unsuitable zones. The area proportion of the most suitable zone for wheat, maize and sunflower within the Heping Village was 27.5, 46.5 and 77.5%, respectively. Most of the most suitable zone occurred in the western part of the village. The results of this study provide the scientific basis for optimizing the local major crop distribution and improving cultural practices management in Hetao Irrigation District.展开更多
By taking Batang Township in Gangnan District,Guigang City,Guangxi Zhuang Autonomous Region for an example,Principal Component Analysis(PCA),GIS technique and SPSS13.0 were applied to comprehensively evaluate 3 princi...By taking Batang Township in Gangnan District,Guigang City,Guangxi Zhuang Autonomous Region for an example,Principal Component Analysis(PCA),GIS technique and SPSS13.0 were applied to comprehensively evaluate 3 principal factors:value of ecological environment,foundation of economic development,value of natural resources;three-dimensional coordinates of economy-ecology-resource combinations were obtained;and finally,functional zoning for the spatial development was realized,22 administrative villages in this town were classified into 6 categories.Among these 6 types of functional zoning,regions of key development and moderate development are Batang Village,Xinlu Village,Suwan Village,Xinmeng Village,Bancun Village,Daxin Village and Gaoxin Village,which are endowed with excellent traffic conditions,solid economic foundation and low sensitivity of ecological environment,thus are suitable to be developed as major spatial carriers of town and industrial development;regions of controlled development are mainly Gaobei Village,Gaoling Village,Sugang Village,Mulong Village and Zhenxin Village,which have moderate economic foundation,dominant crop farming and moderate sensitivity of ecological environment,and also are close to the key developed areas,thus they should be developed with proper control;grey elastic regions mainly include Hengling Village,Sanban Village,Xueshan Village,Shanquan Village and Xinhua Village,which have poor economic foundation and low sensitivity of ecological environment,but excellent natural resources and traffic conditions,thus can be developed as backup land for towns and industrial development;regions of moderate and key protection include Gaolang Village,Cenxi Village,Xin'an Village and Xin'he Village,which have fragile ecological environment and poor economic foundation,thus should be developed according to the principle of "protection first,intensive exploration".展开更多
Functional traits are predictors of plants in response to environmental stimuli. They represent specific functional adaptations to various environmental stresses. This study deals with the variation in plant functiona...Functional traits are predictors of plants in response to environmental stimuli. They represent specific functional adaptations to various environmental stresses. This study deals with the variation in plant functional traits along elevation gradient and land-use types in Sagarmatha National Park and Buffer Zone, Nepal. Two field investigations in April and September, 2011 were made to collect samples. Sampling was done from 2200 - 3800 m asl varying approx. 400 m. East and west facing aspects of each valley were chosen. In each aspect four land-use type categories including disturbed (cultivated land, exploited forest and meadow) and less disturbed natural forest were selected. A transect of 25 m long and 2.5 m wide was laid. Different eight traits of plants including lifeform, plant height, clonality, spinescence, leaf dry matter content, stem specific density, twig dry matter content and twig drying time were examined for 60 plant species belonging to 31 families, collected from 40 sampled plots. Nine different types of growth forms were recorded. Plant height of the investigated species ranged from 0.03 - 15 m. The stolon consisting species were dominant in exploited forests. Diversity of clonal species was more in meadow and non-clonal species were dominant in all the altitudes. Only eight species consisted of spines. In the disturbed land-use categories, we found high variation in a particular trait. Correlation analyses revealed the significant relationship (p < 0.01) among different traits. Herbs and shrubs were dominant at higher elevation and in disturbed land-use categories. Species from high altitude were mostly short basal herbs, while spinescence and tall trees were observed at lower altitudes. Species recorded in meadows and exploited forests showed high variation in traits due to disturbance mainly grazing, fire, litter collection and trampling. Altitudinal variation, climatic conditions and disturbance most strongly influence trait expression in the study area.展开更多
Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relations...Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relationship between neural stem cell status in the subventricular zone and olfactory function in rats with diabetes mellitus.Streptozotocin was injected through the femoral vein to induce type 1 diabetes mellitus in Sprague-Dawley rats.Two months after injection,olfactory sensitivity was decreased in diabetic rats.Meanwhile,the number of Brd U-positive and Brd U+/DCX+double-labeled cells was lower in the subventricular zone of diabetic rats compared with agematched normal rats.Western blot results revealed downregulated expression of insulin receptorβ,phosphorylated glycogen synthase kinase 3β,and β-catenin in the subventricular zone of diabetic rats.Altogether,these results indicate that diabetes mellitus causes insulin deficiency,which negatively regulates glycogen synthase kinase 3β and enhances β-catenin degradation,with these changes inhibiting neural stem cell proliferation.Further,these signaling pathways affect proliferation and differentiation of neural stem cells in the subventricular zone.Dysfunction of subventricular zone neural stem cells causes a decline in olfactory bulb structural plasticity and impairs olfactory sensitivity in diabetic rats.展开更多
We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Us...We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Using automatic supervised classification combined with visual interpretation, we obtained land-use information for five study areas(Nantong, Shanghai, Jiaxing, Ningbo, and Zhoushan). Significant land-use changes have occurred in this area between 1995 and 2015, characterized in particular by large reductions in cultivated land and rapid increases in urbanized land. In addition, land reclamation was very active in this period as an effective supplement to the increased demand for land development: since 1995, 1622 km^2 of land was reclaimed from near-coastal regions in the study area. This increase in urbanization was jointly driven by population, economic, transportation, and policy factors. Urban areas expanded from the center outward in concentric rings, with infrastructure guiding the radial expansion of development along transportation corridors, thus forming a network of connections. Due to the influence of national land regulation policies, the expansion rate of development in the YRD gradually diminished after 2010. This indicates that the area's resource and environmental carrying capacity has reached a saturation stage in which urbanization has transitioned from broad and incremental expansion to the intensive use of land resources.展开更多
Dear Editor, Pregnancy is a physiological condition when immune cells face a dual crisis, as on one hand, the body needs to essentially tolerate semi-allogenic fetus possessing antigens from maternal and paternal side...Dear Editor, Pregnancy is a physiological condition when immune cells face a dual crisis, as on one hand, the body needs to essentially tolerate semi-allogenic fetus possessing antigens from maternal and paternal sides, while on the other hand the maternal as well as the fetal body must not be adversely affected by infections. This delicate balance between immune tolerance and responses is regulated by an orchestra of immune cells. Various immune regulations by B cells are lately being explored. These include the production of asymmetric antibodies, induced by pregnancy factors, providing protection against maternally derived antipaternal symmetric antibodies at the feto-maternal interface[1] to protect the fetus from immune attack by destructive maternal natural killer cells as well as cytotoxic lymphocytes(2)Moreover, the regulatory B cells can inhibit pro-inflammatory responses triggered by T cells and pro inflammatory mediators during pregnancy, by secreting interleukin-10, a potent anti-inflammatory cytokine(3)Interleukin-10, secreted by B cells, also suppresses activities of the dendritic cells and keeps them in an immature state as mature dendritic cells would induce T cells which are detrimental to pregnancy sustenance[4].展开更多
AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential as...AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential associated factors for FOZ.METHODS:A total of 133 patients who received corneal refractive surgery in our hospital between November 2018 and July 2021 were retrospectively enrolled.There were 63 patients(123 eyes)in SMILE group and 70patients(139 eyes)in FS-LASIK group.The size of FOZ was measured using Pentacam 3-dementional anterior segment analyzer before and 3mo after surgery,so as to analyze postoperative achieved functional optical zone(AFOZ)and its contributing parameters.RESULTS:When planned functional optical zone(PFOZ)was 6.5 mm for both groups,AFOZ was 1.45±0.27 and 1.67±0.25 mm smaller than preoperative FOZ in SMILE group and FS-LASIK group 3mo after surgery.AFOZ in SMILE group was significantly larger than that in FS-LASIK group(P<0.001).Variation of FOZ was negatively correlated with preoperative spherical equivalent(SE)and positively correlated with variation of mean keratometry value(△Km),variation of spherical aberration(△SA),and variation of Q-value(△Q,all P<0.001)in both groups.Multiple variable linear regression equations were△FOZ=1.354-0.1×pre-SE+0.336×△Q+1.462×△SA in SMILE group and△FOZ=1.512+0.137×△Q+0.468×△SA in FS-LASIK group.CONCLUSION:AFOZ is significantly smaller than preoperative FOZ in both SMILE and FS-LASIK groups.With the same PFOZ,larger AFOZ is achieved in SMILE group than in FS-LASIK group.展开更多
The effect of a protection zone on a diffusion predator-prey model with Ivlev-type functional response is considered.We discuss the existence and non-existence of positive steady state solutions by using the bifurcati...The effect of a protection zone on a diffusion predator-prey model with Ivlev-type functional response is considered.We discuss the existence and non-existence of positive steady state solutions by using the bifurcation theory.It is shown that the protection zone for prey has beneficial effects on the coexistence of the two species when the growth rate of predator is positive.Moreover,we examine the dependence of the coexistence region on the efficiency of the predator capture of the prey and the protection zone.展开更多
Teleseismic events recorded by stations located in the Adamawa Plateau have been treated using the inversion method of receiver functions. These six stations are part of a network of 32 large strip seismic stations in...Teleseismic events recorded by stations located in the Adamawa Plateau have been treated using the inversion method of receiver functions. These six stations are part of a network of 32 large strip seismic stations installed in Cameroon between 2005 and 2007. This method allowed us to investigate the lithospheric mantle in that region. The results obtained from the velocity model have been compared to some existing results in this region. These results show the existence of a thick crust having an average thickness of about 35.2 km and a corresponding S wave velocity of 3.7 km/s. For an average S wave velocity of 4.4 km/s the lithospheric mantle appears to be thin in nature and has a thickness that varies from 39 km and 49.6 km. Beyond the lower lithospheric mantle, there exists a low velocity zone, whose thickness varies between 20 km and 43.9 km. The variation of the low velocity zone leads to variation of the lower boundary of the lithospheric mantle boundary at the depths ranging from 73.8 km and 85 km.展开更多
A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the app...A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the appropriate development strategy and achieve sustainable development. The major function oriented zoning plays a role in spatial coordination mainly' by spatial guidance and restriction, so. the proposal of major function oriented zoning gives a new train of thought to generate a coordination evaluation of economy-society and the resource-environment system, From the view of major function oriented zoning that considers resource environmental bearing capacity, existing development density and development potential, this paper constructs an index system and model of coordination evahtation with a case study on Pearl River Delta. The results have shown: (I) It can reveal the conflicts of economic-social development and resource-environment quality to ac- curately consider resource environmental bearing capacity, existing development densio~ and development po- tential; (2) The coordination degree between social-economy system and resource-environment system in Pearl River Delta continued to decline in the past 10 years. The spatial extent of coordination evoh,es.from coordina- tion in the whole Pearl River Delta to imbalance in the core areas, and at present, the uncoordinated areas have already diffused from core areas to the outlying regions: (3) Most regions of the Pearl River Delta are in uncoordinated condition When considering the coordination degree of economic-social development and resollrceenvironment quality, not as coordinated as some scholars considered.展开更多
There are a lot of functions of marine resources. The various and competing conflicts between different users and different sectors in the use of marine resources will cause the disorderly development of marine resour...There are a lot of functions of marine resources. The various and competing conflicts between different users and different sectors in the use of marine resources will cause the disorderly development of marine resources, and even destroy the marine ecosystem. Marine functional zoning is an effective tool to solve the conflicts. However, there are some shortcomings in the current understanding on marine functional zoning and its practice. In this paper, a case study on the resource-oriented marine functional zoning of Xiangshan Port is introduced. By the principles of resource-oriented and public participation, Xiangshan Port is divided into seven zones, and the main function of the whole port and seven zones are determined by the environmental economics analysis. A case study of Xiamen is also introduced for how to integrate marine functional zoning into a coastal city conceptual planning. Under the conservation principle, resources-oriented principle and so on, the advantages and disadvantages of natural ecosystem, social ecosystem and economic ecosystem are holistically analyzed, the urban orientation of Xiamen is determined as a regional international tourism city, and the whole city is divided into five function zones according to its leading industry -tourism. Resource-oriented marine functional zoning has a long-term guidance for sustainable use of marine resources and development strategy of a coastal city. And environmental economics analysis is an effective tool for resource-orientation.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41271534)China Scholarship Council(No.201906770044)。
文摘To solve the problems caused by irrational land-use, studying the functions of land-use, its changing characteristics, and the relationship between each land-use function will be beneficial for achieving sustainable land development. In this research, we constructed an evaluation framework of multiple land-use functions(LUFs) based on sustainable land-use theory. Specifically,, we classified the multiple LUFs into three types: agricultural production function(APF), living function(LVF), and ecological service function(ESF).We then spatialized the economic and social data, and implemented the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs) model and RUSLE(Revised Universal Soil Loss Equation) model to evaluate each sub-LUF(crop production, aquatic production, woodlands production, livestock production, living space, life quality, water supply, soil conservation, climate regulation, biological conservation) in central China in 2000 and again in 2015. Moreover, by analyzing the changes to LUFs and the relationships between each LUF change, we were able to discern patterns of LUF change in central China. The results show that: (1)42.12% of total territory in the study area increased their APF from 2000 to 2015, while 43.41% of the lands increased their ESF yet only 8.98% of the lands increased their LVF;(2) in Hubei and Hunan, there was more land with an increase of APF than in Anhui or Jiangxi. The APF in Jiangxi exhibited the greatest decline over time period, the LVF increased more in the provincial capital cities than in other regions, and the ESF expanded more in Jiangxi than in the other provinces;and (3) the changes in APF were significantly and positively correlated with changes in LVF. Additionally, changes in ESF were negatively but non-significantly correlated with changes in APF and LVF.
基金funded by the National Science Foundation of China(Grant No.42161043)the improvement plan of scientific research ability in Northwest Normal University(NWNU-LKQN2020-16).
文摘The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory space.This manuscript analyzed and quantified the impact of EFPZ on the regional water conservation function,based on land use data from 2005,2008,2010,2015 and 2020,by conducting a counterfactual simulation along with the GeoSOS-FLUS model and the InVEST model.The results demonstrate that the delineation of EFPZ can significantly influence the water conservation.(1)From 2010 to 2020,as the EFPZ was implemented,the water conservation in the study area was increasing year by year,with a growth rate of 0.03×10^(8) m^(3)∙a^(-1).On the other hand,the simulated water conservation capacity without the implementation of EFPZ decreased year by year,with a decrease rate of 0.01×10^(8) m^(3)∙a^(-1).(2)The EFPZ accounts for only 23%of the total area,but the contribution rate of water conservation reaches 80%.The actual values of water conservation and average water yield per unit pixel in the EFPZ show an increasing trend both internally and externally,while the counterfactual simulation values exhibit a decreasing trend.(3)The water conservation is much higher within the EFPZ than without EFPZ.The implementation of EFPZ has a significant effect on the improvement of the water conservation capacity in Maqu EFPZ and Yellow River Source EFPZ.The protection effectiveness should be enhanced in Qilian Mountain EFPZ and afforestation activities need to be carefully considered in Loess Plateau EFPZ.
文摘Functional zoning is a critical phase in the planning of parks.Through summarizing and analyzing the functional zoning modes of different urban park types in China,as well as comparing to the functional zoning modes of nature reserves,famous scenic areas and overseas national parks,the functional zoning modes of urban wetland parks in China were elaborated in this study,the assumption of further sectorization were put forward,and theoretical supports were sought for more scientific and operable functional zoning of urban wetland parks.
文摘The evaluation of marine function zoning (hereinafter referred to as MFZ) is an important part of MFZ. This paper studies the principles of MFZ evaluation and the evaluation procedures. It is proposed that three main aspects, including the evaluation of MFZ implementation situation, the evaluation of the performance effects and the evaluation of the changes of dependent conditions, are the top priorities in establishing an evaluation indicator system framework. The evaluation of MFZ implementation situation includes assessing the general situation of MFZ and the degree of implementation and public participation. The evaluation of the performance effects involves the assessments of the achievements and the existing problems in the rectification and standardization of utilizing the sea areas, protecting marine resources and environment, and promoting marine economic development. The evaluation of the changes of dependent conditions includes the assessments and measurements of the changes in the social and economic conditions, the use demands of marine industries, marine resource conditions and marine environmental conditions. This paper provides the means of integrating quantitative and qualitative approaches into the scientific and systematic evaluation on MFZ. The evaluation results can determine whether MFZ needs to be altered or not. The results also provide an important reference basis for determining whether a slight or great alteration is justified. To illustrate the utility of the MFZ evaluation indicator system, an evaluation example is given. Further studies are needed to make the evaluation of MFZ more scientific, reasonable, fair and effective.
基金supported by the National Science and Technology Major Project for Water Pollution Control and Treatment (Grant No. 2017ZX07101001)National Natural Science Foundation of China (Grant NO.41671529)+2 种基金the Hundred Young Talents Program of the Institute of Mountain Hazards and Environment (Grant No. SDSQB-2015-01)the Monitoring and Warning Program for Resources and Environment Carrying Capability in Sichuan Province (Grant No. ZXGH201709)the Program for Resource and Environment Carrying Capability in Jiu ZhaiG ou Earthquake Disaster Area (Grant No. Y7K2190190)
文摘An earthquake in the Jiuzhaigou area caused numerous secondary disasters, such as rolling stones, land collapse, landslides and debris flow, which badly affected the safety of human settlements and influenced the spatial layout of the post-disaster reconstruction. Therefore, carrying out assessments of land and identifying a suitable zone for human habitats were very important. This research creates the territorial suitability assessment and function zoning conceptual model in the earthquake-stricken area, and the new methods of the territorial suitability evaluation system were used to divide the spatial functional zones of the earthquake stricken area, which provide a theoretical guidance and decisionmaking basis for the reconstruction of the disaster area. The results showed that:(1) The Jiuzhaigou earthquake-stricken area comprises of an ecological area that has a high level of importance to the ecosystem. In the earthquake-stricken area, 65% of national land is at an altitude of 3000-4000 m, and therefore not suitable for a high level of intensive reconstruction, but reconstructed in an eco-friendly manner.(2) The zone suitable for reconstruction comprises mainly of the river valley and the flat terrain of western parts. The land with low suitability is mainly located on steep terrain, such as highmountains and low gullies. The geographic and geomorphic conditions limit the spread of a suitable reconstruction zone.(3) The earthquake-stricken area mainly comprises of a tourism industry gathering area, population gathering area, agriculture and animal husbandry development area, and ecological preservation area with areas of 76 km^2, 44 km^2, 1591 km^2 and 7512 km^2, respectively. Scientifically zoning the reconstruction areas using scientific evaluation may provide guidance for the location of reconstruction sites.
基金National Natural'Science Foundation of China, No.40401016
文摘Ecological shelter zones reconstruction is an ecosystem restoration and conservation project aimed to the ecological safety of nations, regions and basins. Reconstruction of ecological shelter zones of the upper reaches of the Yangtze River became one of the most important tasks of Western Development strategy. This article, taking Zhaotong as an example, studies the functional regionalization of ecological shelter zones. The study supplies a case for functional regionalization of small and medium regions whose main tasks are environment reservation. With the guidance of theories of functional regionalization, and based on the analysis of Zhaotong's natural, ecological and socioeconomic factors, the paper suggests five principles for factors selection. These principles include: (1) reversing order evaluation; (2) selecting main factors; (3) keeping the integrality of administrative regions of towns; and (4) making the products acceptable by local government. To analyze spatial status of selected factors, LUCC data in 2002, 1:50,000 relief maps and town-unit socioeconomic statistical data in 2004 are used. RS and GIS tools are also applied to melt traditional and modern geographical methods. This would be useful to functional regionalization research in mountainous areas. As a conclusion, the leading functional regions of ecological conservation or economic development are suggested, respectively. Zhaotong city is divided into two-level functional regions. The first-level includes three leading functional regions and they will lead developing direction of sub-regions. The second-level includes eight sub-regions, which are policy implemented regions, and will supply guidance to Zhaotong's ecological shelter zones reconstruction.
基金Under the auspices of Key Project of National Natural Science Foundation of China (No. 40830741)National Key Technology R&D Program (No. 2008BAH31B01)
文摘Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented.
基金Under the auspices of Grant Program of Clean Development Mechanism Fund of China(CDMF)(No.2014092)Task 2 of Key Service Project 5 for the Characteristic Institute of Chinese Academy of Sciences(No.TSS-2015-014-FW-5-2)+2 种基金National Natural Science Foundation of China(No.41571159)The Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA20010301)Jiangsu Natural Science Foundation(No.BK20181105)
文摘Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divided scientifically to clear its direction of development and protection. Therefore, based on ecological constraints, a beneficial discussion would be about the key ecological function areas adopting the concept of ecological protection restriction and supporting socioeconomic development for spatial function zoning. In this paper, the researchers, taking Tacheng Basin, Xinjiang of China as an example, choose township as basic research unit and set up an evaluation index system from three aspects, namely, ecological protection suitability, agricultural production suitability, and urban development suitability, which are analyzed by using spatial analysis functions and exclusive matrix method. The results showed that: 1) This paper formed a set of multilevel evaluation index systems for three types of spatial function zoning of the key ecological function areas based on a novel perspective by scientifically dividing Tacheng Basin into ecological space, agricultural space, and urban space,which realized the integration and scientific orientation for spatial function at the township scale. 2) Under the guidance of three types of spatial pattern, the functional orientation and suggestions of development and protection was clearly defined for ecological protection zones,ecological economic zones, agricultural production zones, and urban development zones. 3) A new idea of space governance is provided to promote the coordinated and sustainable development between ecology and economy, which can break the traditional mode of thinking about regional economic development, and offers a scientific basis and reference for macro decision-making.
基金National Natural Science Foundation of China, No.40171040Knowledge Innovation Project of theInstitute of Geographic Sciences and Natural Resources Research, CAS, No.CXIOG-A02-03
文摘Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of north central China. In this study, the desertified land was classified into five degrees: potential, light, medium, severe and extreme. The results indicate that the extent of desertification expands slightly, while desertification degree is enhanced significantly. About 22.35% of the total land area in the study area is in the desertification course, and the expanded area of both severely and extremely desertified land accounts for 3.67% of the total area of Mu Us Sandy Land. About 9053 klTl2 of area witnessed changes in land-use types between 1985 and 2000, which accounted for 10.75% of the total. More importantly, the area of conversions among cultivated land, forestland and rangeland added up to 971.6 km^2. This research reveals that both improper land-use types and conversions could accelerate the desertification process. Both cultivated land and forestland have more effects on the desertification development than rangeland. Some land-use type conversions, such as rangeland to cultivated land, rangeland to forestland and forestland to cultivated land, are attributed to the acceleration of the desertification development while the opposite can control the desertification development.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest, China (2009030012-3)
文摘Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat (Triticum aestinum L.), maize (Zea mays L.) and sunflower (Helianthus annuus L.), growing in 76 farm fields are evaluated with modified discount function. Salinity ecological zones appropriate for these local crops are characterized and a case study is presented for crop salinity ecological zoning. The results show that the yield reductions of wheat, maize and sunflower when grown in saline soils are attributed primarily to a reduction in spikelet number, 1 000-grain weight and seed number per head, respectively. Sunflower is the most tolerant crop among the three which had a salinity tolerance index (ST-index) of 12.24, followed by spring maize and spring wheat with ST-Indices of 9.00 and 7.43, respectively. According to the crop salinity tolerance results, the arable land in the Heping Village of this district was subdivided into four salinity ecological zones: the most suitable, suitable, sub-suitable and unsuitable zones. The area proportion of the most suitable zone for wheat, maize and sunflower within the Heping Village was 27.5, 46.5 and 77.5%, respectively. Most of the most suitable zone occurred in the western part of the village. The results of this study provide the scientific basis for optimizing the local major crop distribution and improving cultural practices management in Hetao Irrigation District.
文摘By taking Batang Township in Gangnan District,Guigang City,Guangxi Zhuang Autonomous Region for an example,Principal Component Analysis(PCA),GIS technique and SPSS13.0 were applied to comprehensively evaluate 3 principal factors:value of ecological environment,foundation of economic development,value of natural resources;three-dimensional coordinates of economy-ecology-resource combinations were obtained;and finally,functional zoning for the spatial development was realized,22 administrative villages in this town were classified into 6 categories.Among these 6 types of functional zoning,regions of key development and moderate development are Batang Village,Xinlu Village,Suwan Village,Xinmeng Village,Bancun Village,Daxin Village and Gaoxin Village,which are endowed with excellent traffic conditions,solid economic foundation and low sensitivity of ecological environment,thus are suitable to be developed as major spatial carriers of town and industrial development;regions of controlled development are mainly Gaobei Village,Gaoling Village,Sugang Village,Mulong Village and Zhenxin Village,which have moderate economic foundation,dominant crop farming and moderate sensitivity of ecological environment,and also are close to the key developed areas,thus they should be developed with proper control;grey elastic regions mainly include Hengling Village,Sanban Village,Xueshan Village,Shanquan Village and Xinhua Village,which have poor economic foundation and low sensitivity of ecological environment,but excellent natural resources and traffic conditions,thus can be developed as backup land for towns and industrial development;regions of moderate and key protection include Gaolang Village,Cenxi Village,Xin'an Village and Xin'he Village,which have fragile ecological environment and poor economic foundation,thus should be developed according to the principle of "protection first,intensive exploration".
文摘Functional traits are predictors of plants in response to environmental stimuli. They represent specific functional adaptations to various environmental stresses. This study deals with the variation in plant functional traits along elevation gradient and land-use types in Sagarmatha National Park and Buffer Zone, Nepal. Two field investigations in April and September, 2011 were made to collect samples. Sampling was done from 2200 - 3800 m asl varying approx. 400 m. East and west facing aspects of each valley were chosen. In each aspect four land-use type categories including disturbed (cultivated land, exploited forest and meadow) and less disturbed natural forest were selected. A transect of 25 m long and 2.5 m wide was laid. Different eight traits of plants including lifeform, plant height, clonality, spinescence, leaf dry matter content, stem specific density, twig dry matter content and twig drying time were examined for 60 plant species belonging to 31 families, collected from 40 sampled plots. Nine different types of growth forms were recorded. Plant height of the investigated species ranged from 0.03 - 15 m. The stolon consisting species were dominant in exploited forests. Diversity of clonal species was more in meadow and non-clonal species were dominant in all the altitudes. Only eight species consisted of spines. In the disturbed land-use categories, we found high variation in a particular trait. Correlation analyses revealed the significant relationship (p < 0.01) among different traits. Herbs and shrubs were dominant at higher elevation and in disturbed land-use categories. Species from high altitude were mostly short basal herbs, while spinescence and tall trees were observed at lower altitudes. Species recorded in meadows and exploited forests showed high variation in traits due to disturbance mainly grazing, fire, litter collection and trampling. Altitudinal variation, climatic conditions and disturbance most strongly influence trait expression in the study area.
基金partly supported by the National Natural Science Foundation of China,No.81370448,81570725
文摘Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relationship between neural stem cell status in the subventricular zone and olfactory function in rats with diabetes mellitus.Streptozotocin was injected through the femoral vein to induce type 1 diabetes mellitus in Sprague-Dawley rats.Two months after injection,olfactory sensitivity was decreased in diabetic rats.Meanwhile,the number of Brd U-positive and Brd U+/DCX+double-labeled cells was lower in the subventricular zone of diabetic rats compared with agematched normal rats.Western blot results revealed downregulated expression of insulin receptorβ,phosphorylated glycogen synthase kinase 3β,and β-catenin in the subventricular zone of diabetic rats.Altogether,these results indicate that diabetes mellitus causes insulin deficiency,which negatively regulates glycogen synthase kinase 3β and enhances β-catenin degradation,with these changes inhibiting neural stem cell proliferation.Further,these signaling pathways affect proliferation and differentiation of neural stem cells in the subventricular zone.Dysfunction of subventricular zone neural stem cells causes a decline in olfactory bulb structural plasticity and impairs olfactory sensitivity in diabetic rats.
基金supported by China-ASEAN maritime cooperation fund: Comparative Study of Holocene Sedimentary Evolution of the Yangtze River Delta and the Red River Deltathe Natural Science Foundation of Shandong Province, China (No. ZR2014DQ020)+1 种基金China Geological Survey Project (No. DD20160145)the National Natural Science Foundation of China (Nos. 41706074 and 41506107)
文摘We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Using automatic supervised classification combined with visual interpretation, we obtained land-use information for five study areas(Nantong, Shanghai, Jiaxing, Ningbo, and Zhoushan). Significant land-use changes have occurred in this area between 1995 and 2015, characterized in particular by large reductions in cultivated land and rapid increases in urbanized land. In addition, land reclamation was very active in this period as an effective supplement to the increased demand for land development: since 1995, 1622 km^2 of land was reclaimed from near-coastal regions in the study area. This increase in urbanization was jointly driven by population, economic, transportation, and policy factors. Urban areas expanded from the center outward in concentric rings, with infrastructure guiding the radial expansion of development along transportation corridors, thus forming a network of connections. Due to the influence of national land regulation policies, the expansion rate of development in the YRD gradually diminished after 2010. This indicates that the area's resource and environmental carrying capacity has reached a saturation stage in which urbanization has transitioned from broad and incremental expansion to the intensive use of land resources.
文摘Dear Editor, Pregnancy is a physiological condition when immune cells face a dual crisis, as on one hand, the body needs to essentially tolerate semi-allogenic fetus possessing antigens from maternal and paternal sides, while on the other hand the maternal as well as the fetal body must not be adversely affected by infections. This delicate balance between immune tolerance and responses is regulated by an orchestra of immune cells. Various immune regulations by B cells are lately being explored. These include the production of asymmetric antibodies, induced by pregnancy factors, providing protection against maternally derived antipaternal symmetric antibodies at the feto-maternal interface[1] to protect the fetus from immune attack by destructive maternal natural killer cells as well as cytotoxic lymphocytes(2)Moreover, the regulatory B cells can inhibit pro-inflammatory responses triggered by T cells and pro inflammatory mediators during pregnancy, by secreting interleukin-10, a potent anti-inflammatory cytokine(3)Interleukin-10, secreted by B cells, also suppresses activities of the dendritic cells and keeps them in an immature state as mature dendritic cells would induce T cells which are detrimental to pregnancy sustenance[4].
基金Supported by Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2022L201)。
文摘AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential associated factors for FOZ.METHODS:A total of 133 patients who received corneal refractive surgery in our hospital between November 2018 and July 2021 were retrospectively enrolled.There were 63 patients(123 eyes)in SMILE group and 70patients(139 eyes)in FS-LASIK group.The size of FOZ was measured using Pentacam 3-dementional anterior segment analyzer before and 3mo after surgery,so as to analyze postoperative achieved functional optical zone(AFOZ)and its contributing parameters.RESULTS:When planned functional optical zone(PFOZ)was 6.5 mm for both groups,AFOZ was 1.45±0.27 and 1.67±0.25 mm smaller than preoperative FOZ in SMILE group and FS-LASIK group 3mo after surgery.AFOZ in SMILE group was significantly larger than that in FS-LASIK group(P<0.001).Variation of FOZ was negatively correlated with preoperative spherical equivalent(SE)and positively correlated with variation of mean keratometry value(△Km),variation of spherical aberration(△SA),and variation of Q-value(△Q,all P<0.001)in both groups.Multiple variable linear regression equations were△FOZ=1.354-0.1×pre-SE+0.336×△Q+1.462×△SA in SMILE group and△FOZ=1.512+0.137×△Q+0.468×△SA in FS-LASIK group.CONCLUSION:AFOZ is significantly smaller than preoperative FOZ in both SMILE and FS-LASIK groups.With the same PFOZ,larger AFOZ is achieved in SMILE group than in FS-LASIK group.
基金Supported by the National Natural Science Foundation of China(11761063).
文摘The effect of a protection zone on a diffusion predator-prey model with Ivlev-type functional response is considered.We discuss the existence and non-existence of positive steady state solutions by using the bifurcation theory.It is shown that the protection zone for prey has beneficial effects on the coexistence of the two species when the growth rate of predator is positive.Moreover,we examine the dependence of the coexistence region on the efficiency of the predator capture of the prey and the protection zone.
文摘Teleseismic events recorded by stations located in the Adamawa Plateau have been treated using the inversion method of receiver functions. These six stations are part of a network of 32 large strip seismic stations installed in Cameroon between 2005 and 2007. This method allowed us to investigate the lithospheric mantle in that region. The results obtained from the velocity model have been compared to some existing results in this region. These results show the existence of a thick crust having an average thickness of about 35.2 km and a corresponding S wave velocity of 3.7 km/s. For an average S wave velocity of 4.4 km/s the lithospheric mantle appears to be thin in nature and has a thickness that varies from 39 km and 49.6 km. Beyond the lower lithospheric mantle, there exists a low velocity zone, whose thickness varies between 20 km and 43.9 km. The variation of the low velocity zone leads to variation of the lower boundary of the lithospheric mantle boundary at the depths ranging from 73.8 km and 85 km.
基金supported by National Social Science Fund(Grant No. 06&ZD038)The 11th Five-Year Planning programme of philosophy and Social Science of Guangdong(Grant NO.07D04)
文摘A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the appropriate development strategy and achieve sustainable development. The major function oriented zoning plays a role in spatial coordination mainly' by spatial guidance and restriction, so. the proposal of major function oriented zoning gives a new train of thought to generate a coordination evaluation of economy-society and the resource-environment system, From the view of major function oriented zoning that considers resource environmental bearing capacity, existing development density and development potential, this paper constructs an index system and model of coordination evahtation with a case study on Pearl River Delta. The results have shown: (I) It can reveal the conflicts of economic-social development and resource-environment quality to ac- curately consider resource environmental bearing capacity, existing development densio~ and development po- tential; (2) The coordination degree between social-economy system and resource-environment system in Pearl River Delta continued to decline in the past 10 years. The spatial extent of coordination evoh,es.from coordina- tion in the whole Pearl River Delta to imbalance in the core areas, and at present, the uncoordinated areas have already diffused from core areas to the outlying regions: (3) Most regions of the Pearl River Delta are in uncoordinated condition When considering the coordination degree of economic-social development and resollrceenvironment quality, not as coordinated as some scholars considered.
文摘There are a lot of functions of marine resources. The various and competing conflicts between different users and different sectors in the use of marine resources will cause the disorderly development of marine resources, and even destroy the marine ecosystem. Marine functional zoning is an effective tool to solve the conflicts. However, there are some shortcomings in the current understanding on marine functional zoning and its practice. In this paper, a case study on the resource-oriented marine functional zoning of Xiangshan Port is introduced. By the principles of resource-oriented and public participation, Xiangshan Port is divided into seven zones, and the main function of the whole port and seven zones are determined by the environmental economics analysis. A case study of Xiamen is also introduced for how to integrate marine functional zoning into a coastal city conceptual planning. Under the conservation principle, resources-oriented principle and so on, the advantages and disadvantages of natural ecosystem, social ecosystem and economic ecosystem are holistically analyzed, the urban orientation of Xiamen is determined as a regional international tourism city, and the whole city is divided into five function zones according to its leading industry -tourism. Resource-oriented marine functional zoning has a long-term guidance for sustainable use of marine resources and development strategy of a coastal city. And environmental economics analysis is an effective tool for resource-orientation.