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1.
Soil erosion by wind is one of the most important processes in the changing the earth’s surface in semi-arid areas,Thus it is of great importance to study soil-erosion action.Using integrated technologies of remote sensing and geochemistry radioactivity iso-tope to extract regional soil-erosion information and to calculate quantity of soil erosion is accomplished successfully in this paper by means of beneficial experiments in the Talatan region of the Gonghe Basin,which is located in northeastern Qinghai-Tibet Pla-teau in China.The results show that the soil erosion by wind is not intensive in this region;the erosion types belong to the classes of very-soft erosion and soft-erosion type,which account for 47.12 percent and 35.58 percent,respectively,of the total study area.In total,two kinds of soil erosion account for 82.70 percent of the study area;only a small area belongs to the classes of severe erosion and very-severe erosion;this area is about 22.14 km2.Severe deposition activity has taken place in this region,and has appeared in a large area(322.67 km2),which accounts for 11.78 percent of the total study area.The results of this study show that soil erosion and deposition inventories are 870,000-1,150,000 tons and 550,000-780,000 tons,respectively,per year.The soil in-ventory shows about 320,000-370,000 tons from Talatan to Longyangxia reservoir per year.Using remote-sensing technology and 137Cs techniques is a valid means to analyze and to evaluate the quantity of soil erosion by wind in semi-arid environments.  相似文献   

2.
中国畜禽养殖的空间分析及分区研究(英文)   总被引:2,自引:1,他引:2  
The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world’s top first in recent 20 years. Livestock emissions and pollution is closely associated with its population and spatial distribution. This paper aims to investigate the spatial patterns of livestock and poultry breeding in China. Using statistical yearbook and agricultural survey in 2007, the county-level populations of livestock and poultry are estimated as equivalent standardized pig index (ESP), per cultivated land pig index (PCLP) and per capita pig index (PCP). With the help of spatial data analysis (ESDA) tools in Geoda and ArcGIS software, especially the Moran’s I and LISA statistics, the nationwide global and local clustering trends of the three indicators are examined respectively. The Moran’s I and LISA analysis shows that ESP and PCP are significantly clustering both globally and locally. However, PCLP is clustering locally but not significant globally. Furthermore, the thematic map series (TMS) and related gravity centers curve (GCC) are introduced to explore the spatial patterns of livestock and poultry in China. The indicators are classified into 16 levels, and the GCCs for the three indicators from level 1 to 16 are discussed in detail. For districting purpose, each interval between gravity centers of near levels for all the three indicators is calculated, and the districting types of each indicator are obtained by merging adjacent levels. The districting analysis for the three indicators shows that there exists a potential uniform districting scheme for China’s livestock and poultry breeding. As a result, the China’s livestock and poultry breeding would be classified into eight types: extremely sparse region, sparse region, relatively sparse region, normally sparse region, normal region, relatively concentrated region, concentrated region and highly concentrated region. It is also found that there exists a clear demarcation line between the concentrated and the sparse regions. The line starts from the county boundary between Xin Barag Left Banner and Xin Barag Right Banner, Inner Mongolia Autonomous Region to the west coast of Dongfang County, Hainan Province.  相似文献   

3.
From the development of modern transportation to the current era of high-speed transportation networks, the Beijing-Tianjin-Hebei(BTH) region has always played a national leading role in land transportation development of China. In order to explore the long-term evolutionary characteristics of land transportation in the BTH region, this paper utilized a temporal scale of 100 years to systematically interpret the development process of the land transportation network. Taking 13 cities within the BTH region as research anchor cities, we took into account "leaping" mode of transportation in order to investigate the evolution of accessibility. Our research shows the following results:(1) The land transportation network in the BTH region has undergone five stages of development: the initial period of modernization(1881–1937); the period of stagnation of transportation development(1937–1949); the network expansion period(1949–1980); the period of trunk construction(1980–1995), and the period of high-speed transportation network development(1995–present). The network structure centered around Beijing has existed from the outset of modern transportation development.(2) The accessibility spatial pattern of land transportation in BTH region has evolved from expansion along traffic corridors to the formation of concentric circles. The stratified circular structure of transportation in anchor cities has gradually developed into a contiguous development pattern.(3) There are clear hierarchical differences in the transportation structures of anchor cities. Beijing has always been at the top of this hierarchy, while the hierarchical position of Zhangjiakou has fallen noticeably since 1949. The Beijing-Tianjin region was the first region to form a short-duration transportation circle structure, while the transportation advantages of the central part of Hebei Province, which is located in the center of the BTH transportation region, have yet to be realized.  相似文献   

4.
The Three-River Headwaters region in China is an ecological barrier providing environmental protection and regional sustainable development for the mid-stream and downstream areas, which also plays an important role in animal husbandry in China. This study estimated the grassland yield in the Three-River Headwaters region based on MODIS NPP data, and calculated the proper livestock-carrying capacity of the grassland. We analyzed the overgrazing number and its spatial distribution characteristics through data comparison between actual and proper livestock-carrying capacity. The results showed the following:(1) total grassland yield(hay) in the Three-River Headwaters region was 10.96 million tons in 2010 with an average grassland yield of 465.70 kg/hm2(the spatial distribution presents a decreasing trend from the east and southeast to the west and northwest in turn);(2) the proper livestock-carrying capacity in the Three-River Headwaters region is 12.19 million sheep units(hereafter described as "SU"), and the average stocking capacity is 51.27 SU [the proper carrying capacity is above 100 SU/km2in the eastern counties, 60 SU/km2in the central counties(except Madoi County), and 30 SU/km2in the western counties]; and(3) total overgrazing number was 6.52 million SU in the Three-River Headwaters region in 2010, with an average overgrazing ratio of 67.88% and an average overgrazing number of 27.43 SU/km2. A higher overgrazing ratio occurred in Tongde, Xinghai, Yushu, Henan and Zêkog. There was no overgrazing in Zhiduo, Tanggula Township and Darlag, Qumerleb and Madoi. The remainder of the counties had varying degrees of overgrazing.  相似文献   

5.
The Three-River Headwaters Region(TRHR), which is the source area of the Yangtze River, Yellow River, and Lancang River, is of key importance to the ecological security of China. Because of climate changes and human activities, ecological degradation occurred in this region. Therefore, "The nature reserve of Three-River Source Regions" was established, and "The project of ecological protection and construction for the Three-River Headwaters Nature Reserve" was implemented by the Chinese government. This study, based on MODIS-NDVI and climate data, aims to analyze the spatiotemporal changes in vegetation coverage and its driving factors in the TRHR between 2000 and 2011, from three dimensions. Linear regression, Hurst index analysis, and partial correlation analysis were employed. The results showed the following:(1) In the past 12 years(2000–2011), the NDVI of the study area increased, with a linear tendency being 1.2%/10a, of which the Yangtze and Yellow River source regions presented an increasing trend, while the Lancang River source region showed a decreasing trend.(2) Vegetation coverage presented an obvious spatial difference in the TRHR, and the NDVI frequency was featured by a bimodal structure.(3) The area with improved vegetation coverage was larger than the degraded area, being 64.06% and 35.94%, respectively during the study period, and presented an increasing trend in the north and a decreasing trend in the south.(4) The reverse characteristics of vegetation coverage change are significant. In the future, degradation trends will be mainly found in the Yangtze River Basin and to the north of the Yellow River, while areas with improving trends are mainly distributed in the Lancang River Basin.(5) The response of vegetation coverage to precipitation and potential evapotranspiration has a time lag, while there is no such lag in the case of temperature.(6) The increased vegetation coverage is mainly attributed to the warm-wet climate change and the implementation of the ecological protection project.  相似文献   

6.
An inverse model is used to infer the circulation in Prydz Bay and its adjacent open ocean using hydrographic data obtained by the cruise of the 7th Chinese National Antarctic Research Expedition (CHINARE-7), 1990/91. Barotropie components are found to be strong in the study area, esp. at the Antarctic Divergence, and from a whole view, the velocity is rather small. In the open ocean, the flow is quasizonal, but outside the bay it shows a tendency of pressing onto the shelf from surface to bottom, and a feature of intensification just east of Fram Bank. We suggest here be the most important place to detect the possibility of the Antarctic Bottom Water formation. The meridional profiles of the distribution indicate a strong (relative to the ambient) core and a slope-trapped part into the bargain. In the southeastern part of the bay, there seems to exist a strong coastal current flowing westward. The computed upwelling centers are mainly situated in the west of the study region, as agrees quite well with  相似文献   

7.
Based on a 0.5°×0.5° daily gridded precipitation dataset and observations in meteorological stations released by the National Meteorological Information Center,the interannual variation of areal precipitation in the Qilian Mountains during 1961–2012 is investigated using principal component analysis(PCA) and regression analysis,and the relationship between areal precipitation and drought accumulation intensity is also analyzed.The results indicate that the spatial distribution of precipitation in the Qilian Mountains can be well reflected by the gridded dataset.The gridded data-based precipitation in mountainous region is generally larger than that in plain region,and the eastern section of the mountain range usually has more precipitation than the western section.The annual mean areal precipitation in the Qilian Mountains is 724.9×108 m3,and the seasonal means in spring,summer,autumn and winter are 118.9×108 m3,469.4×108 m3,122.5×108 m3 and 14.1×108 m3,respectively.Summer is a season with the largest areal precipitation among the four seasons,and the proportion in summer is approximately 64.76%.The areal precipitation in summer,autumn and winter shows increasing trends,but a decreasing trend is seen in spring.Among the four seasons,summer have the largest trend magnitude of 1.7×108 m3?a–1.The correlation between areal precipitation in the mountainous region and dry-wet conditions in the mountains and the surroundings can be well exhibited.There is a negative correlation between drought accumulation intensity and the larger areal precipitation is consistent with the weaker drought intensity for this region.  相似文献   

8.
The Yangtze River Delta(YRD) is a region in China with a serious contradiction between economic growth and environmental pollution. Exploring the spatiotemporal effects and influencing factors of air pollution in the region is highly important for formulating policies to promote the high-quality development of urban industries. This study uses the spatial Durbin model(SDM) to analyze the local direct and spatial spillover effects of industrial transformation on air pollution and quantifies the contribution of each factor. From 2008 to 2018, there was a significant spatial agglomeration of industrial sulfur dioxide emissions(ISDE) in the YRD, and every 1% increase in ISDE led to a synchronous increase of 0.603% in the ISDE in adjacent cities. The industrial scale index(ISCI) and industrial structure index(ISTI), as the core factors of industrial transformation, significantly affect the emissions of sulfur dioxide in the YRD, and the elastic coefficients are 0.677 and-0.368, respectively. The order of the direct effect of the explanatory variables on local ISDE is ISCI>ISTI>foreign direct investment(FDI)>enterprise technological innovation(ETI)>environmental regulation(ER)> per capita GDP(PGDP). Similarly, the order of the spatial spillover effect of all variables on ISDE in adjacent cities is ISCI>PGDP>FDI>ETI>ISTI>ER, and the coefficients of the ISCI and ISTI are 1.531 and 0.113, respectively. This study contributes to the existing research that verifies the environmental Kuznets curve in the YRD, denies the pollution heaven hypothesis, indicates the Porter hypothesis, and provides empirical evidence for the formation mechanism of regional environmental pollution from a spatial spillover perspective.  相似文献   

9.
Urban-rural integration (URI) is a new idea to guide the urban-rural transformation in China, and exploring the spatio-temporal characteristics and driving mechanism of URI in China is an urgent need to overcome the dilemmas of insufficient rural development and unbalanced urban and rural development. Based on the process framework of "foundation-motivation-result" of URI, an evaluation indicator system was constructed. The improved entropy evaluation model and the kernel density estimation method were used to quantitatively measure the spatiotemporal evolution characteristics of URI level of 31 provinces, autonomous regions, and municipalities in China's mainland from 2000 to 2020. This study further used the Geodetector to explore the heterogeneous evolution of driving factors for URI level in different regions of China. The main conclusions are as follows: 1) From 2000 to 2020, the URI level in China decreased first and then increased, showing a √-shaped trend, and its spatial differences narrowed. 2) The URI level in China presented a spatial pattern of high in the east and low in the west, divided by the Hu Huanyong Line. The high-value centers showed prominent polarization characteristics and presented a zonal aggregation trend. The medium-value areas were clustered but weakened,and showed a spreading trend from the eastern to the central and western parts. 3) At the national scale, the core influencing factors of URI level were population mobility, economic development level, urban-rural income gap, and educational supports, potential factors were the optimization of industrial structure and the opening-up level, and threshold effect existed in investment benefit and government intervention. At the regional scale, the core driving forces of URI level in China showed obvious spatial heterogeneity, and in 2020 they were economic development level, investment benefit, and government intervention in the eastern region, investment benefit, opening-up level, and urban-rural income gap in the central region, are educational supports, government intervention, and the optimization of industrial structure in the western region. The interaction of driving factors had far more influence on URI level in China than individual factors, and the interaction between traffic accessibility and other socioeconomic factors had been significantly enhanced. Research on the spatio-temporal evolution and mechanism of URI in China can provide theoretical basis for rural revitalization and high-quality urban and rural development. © 2023, Editorial office of PROGRESS IN GEOGRAPHY. All rights reserved.  相似文献   

10.
The Arab region covers an area over 13 million square kilometers in size, with almost 90% of its area classified as arid or extremely arid with very little precipitation, extremely high evaporation and almost no vegetation cover. The region is classified in many international reports as the poorest region in the world in the context of renewable water resources and critical water scarcity which hinders the socio-economic development of many countries in this region. The rapidly increasing population has reduced the per capita share of renewable water to less than the poverty line of 1,000 m 3 /(capita·a) and, in some Arab countries, to less than the extreme poverty line of 500 m 3 /(capita·a). This has led to over-exploitation of non-renewable groundwater and desalination of salty water in many countries with considerable costs and contamination of many renewable sources. Atmospheric processes responsible for aridity in the Arab region are projected to intensify due to climate change, resulting in an alarming decrease in precipitation and increase in evaporation rates. Many concerned entities in the region consider water security as a key element for food security and ultimately political stability. Hence, various efforts have been exerted to identify key problems and suggested solutions. The Arab Water Ministers Council of the Arab League, as well as Reports of the Arab Forum for the Environment and Development (AFED) and the recommendations of the 13th Regional Meeting of the Arab National Committees of the International Hydrological Programme of UNESCO (IHP), have all made similar recommendations on the need to address the issues of water scarcity in the Arab region which will be further discussed in this paper. However, none of these reports focused on "Water Conservation" as an equally important action for coping with water scarcity in the region. There are many definitions for "Water Conservation" in the scientific literature, including huge water savings from irrigation, industrial use, and domestic use as well as methods and approaches for augmenting water supply through non-conventional practices such as water harvesting and waste water reuse. In this paper, a review is provided for definitions, methods and impacts of water conservation and its role in alleviating water scarcity in the Arab region.  相似文献   

11.
Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy–environment–economy system. Using the slacks-based measure(SBM) model considering undesirable output, this study first measures the energy eco-efficiency of provinces in China from 1997 to 2012. It then analyzes the spatial distribution and evolution of energy eco-efficiency from three aspects: scale, intensity, and grain of spatial patterns. Finally, it examines the spatial spillover effects and influencing factors of energy eco-efficiency in different provinces by means of a spatial econometric model. The following conclusions are drawn:(1) The overall energy eco-efficiency is relatively low in China, with energy-inefficient regions accounting for about 40%. Guangdong, Hainan and Fujian provinces enjoy the highest energy eco-efficiency, while Ningxia, Gansu, Qinghai, and Xinjiang are representative regions with low efficiency. Thus, the pattern of evolution of China's overall energy eco-efficiency is U-shaped. Among local regions, four main patterns of evolution are found: increasing, fluctuating, mutating, and leveling.(2) At the provincial level, China's energy eco-efficiency features significant spatial agglomeration both globally and locally. High–high agglomeration occurs mainly in the eastern and southern coastal regions and low–low agglomeration in the northwestern region and the middle reaches of the Yellow River. Changes in spatial patterns have occurred mainly in areas with high–low and low–high agglomeration, with the most remarkable change taking place in the Beijing–Tianjin–Hebei region.(3) There exist significant spatial effects of energy eco-efficiency among provinces in China. For the energy eco-efficiency of a given region, spatial spillovers from adjacent regions outweigh the influence of errors in adjacent regions. Industrial structure has the greatest influence on energy eco-efficiency.  相似文献   

12.
Paleo-environmental changes in the Yangtze Delta during past 8000 years   总被引:2,自引:0,他引:2  
The Yangtze Delta is one of the economically most developed areas in China. It is located in the eastern China monsoon region. Archaeological excavations and environment-archaeology studies over many years in this region provide exceptional information about climate changes, development of human civilization and also human-environment interactions. Archaeological excavations made in the study region reveal that the development of Neolithic cultures is not continuous, which may be a result of extreme climatic events. The analysis of ^14C-dated buried paleotrees, peat and shell ridges show the rise and fall of human civilization in the study area. The research results presented in this paper confirm that human civilization collapsed six times in the Yangtze Delta, matching six high sea level epoches, peat accumulation and buried paleotrees formation periods respectively. This indicates that human activities in the Yangtze Delta are controlled by local climate changes and changing hydrological conditions. The collapse of the Liangzhu culture (5000 aBP-3800 aBP) in about 4000 aBP, after a tremendous flooding event, followed by a relatively backward Maqiao culture (3800 aBP-3200 aBP) confused researchers and aroused their great interest. The research results in this paper show that the collapse of the Liangzhu culture is a result of several factors, for example war and food shortage, but the flooding event occurred in the late Liangzhu culture epoch is the main factor therein.  相似文献   

13.
The Hexi Inland River Basin in an arid region of northwestern China was chosen as the study area for this research. The authors define the vulnerability of an oasis social-ecological system to glacier change; select 16 indicators from natural and socioeconomic systems according to exposure, sensitivity, and adaptive capacity; and construct a vulnerability-assessment indicator system aimed at an inland river basin in the arid region of Northwestern China. Vulnerability of the oasis socialecological system affected by glacier change in the study area is evaluated by Spatial Principal Component Analysis(SPCA) under the circumstance of glacier change. The key factors affecting the vulnerability are analyzed. The vulnerability of the oasis social-ecological system in the Hexi Inland River Basin affected by glacier change is of more than medium grade, accounting for about 48.0% of the total number of counties in the study area. In terms of the spatial pattern of the vulnerability, the oasis economic belt is the most vulnerable. With the rapid development of the area's society and economy, the exposure of the system to glacial changes is significantly increased; and an increase in glacial meltwater is not enough to overcome the impact of increased exposure, which is the main reason for the high vulnerability. Based on the result of the vulnerability analysis and combined with the present industrial structure in the Hexi Inland River Basin, near-,medium-, and long-term adaptation initiatives are put forward in the article.  相似文献   

14.
High-quality cultivation of specialized and sophisticated enterprises that produce new and unique products is an important starting point for consolidating the security foundation of China's industrial chain and supply chain. Using buffer zone analysis and the multi-scale geographically weighted regression (MGWR) model, this study explored the spatial distribution of specialized and sophisticated enterprises that produce new and unique products in the Yangtze River Delta region and influencing factors in 2021. The study found that: 1) Spatially, Shanghai is the main area where specialized and sophisticated enterprises that produce new and unique products are concentrated, followed by provincial capitals and cities on the coast and along rivers; The overall composition of the industry is unbalanced, and the real economic industries such as machinery and equipment manufacturing and high-tech manufacturing account for a relatively high proportion, but there are differences in different regions. 2) In terms of spatial agglomeration, differences between circles and the scale effect are obvious. Within each province, the spatial distribution of specialized and sophisticated enterprises that produce new and unique products in different cities is uneven. Region-wide, the overall spatial distribution pattern of "one pole and multiple cores" is evident. Shanghai is the main agglomeration area for these enterprises, and the provincial capital cities and cities that are the regional economic centers are the secondary agglomeration areas of these enterprises. 3) The four dimensions of influencing factors—physical geography, government, market, and society—have a scale effect on the spatial distribution of specialized and sophisticated enterprises that produce new and unique products. The degree of land development acts at a small scale, which is a local variable, and shows a large difference in the impact on the spatial distribution of these enterprises across the region. Factors such as elevation, government-business relationship, degree of marketization, number and scale of enterprises, degree of openness, logistics development level, and innovation environment are global variables, and except that the degree of marketization and the number of enterprises have a significant negative impact on the spatial distribution of these enterprises, the impact of all other factors is significantly positive. The research results can provide support for the optimization of the layout of new special expertise enterprise space in the Yangtze River Delta region, in order to provide reference for the formulation of new special expertise policies and industrial planning. © 2023, Editorial office of PROGRESS IN GEOGRAPHY. All rights reserved.  相似文献   

15.
Based on the cost-benefit data (1980-2002) of farm products and China Agriculture Yearbooks, this paper studies the regional disparity in the changes of the agricultural land use in China during the period 1980-2002 from three aspects such as the degree of intensity, the sown area and the abandoned farmland. The results show that: (1) The degree of intensity of land use in the westena region during 1980-2000 has a strong uptrend, but in the eastern and central regions the degree of intensity descends obviously and has shown a continuous downtrend since 1997. (2) The total sown area shrinks notably in the eastern region, while it enlarges constantly in the western region. (3) The sown area in the eastern, central and western regions has gone through a similar cyclic process: down (1980-1985)-up (1985-1991)-down (1991-1994)-up (1994-1999)-down (1999-2002). However, there are obvious differences in amplitude variation and tendency among them. The sown area has shrunk in the eastern region and expanded in the central and western regions especially before 1999. (4) The most cases of abandoned farmland are reported in the central region, the second in the eastern region and the least in the western region. The abandonment phenomena chiefly occurred during 1992-1995 in the eastern region, and during 1998-2002 in the central region.  相似文献   

16.
Qin Dahe 《极地研究》1990,2(1):10-19
The densification process within the near-surface layer of Antarctic Ice Sheet is dominated by the environment and exhibits geographic zonality, In this article, the processes are found to be of three types: warm, cold and alternate, on the basis of the studies on a lot of shallow snow/firm cores from Wilkes Land, Antarctica, and the available data. Warm type densification takes place mainly on the periphery of the Antarctic Ice Sheet, where the mean annual temperature is about --10----15℃. High temperature in summer and consequent melting and infiltration are the main factors influencing the densification process. Cold type densification occurs in the huge central region of the Antarctica, where the mean annual temperature is below --25℃, with the maximum below 0℃ in summer. In this region, ice sintering is a main cause for the densification. The alternate type densification occurs in the transition zone between the above two regions, where the mean annual temperature is --15----25℃ and the highest  相似文献   

17.
A model study is conducted to examine the role of Pacific water in the dramatic retreat of arctic sea ice during summer 2007.The model generally agrees with the observations in showing considerable seasonal and interannual variability of the Pacific water inflow at Bering Strait in response to changes in atmospheric circulation. During summer 2007 anomalously strong southerly winds over the Pacific sector of the Arctic Ocean strengthen the ocean circulation and bring more Pacific water into the Arctic than the recent(2000-2006) average.The simulated summer(3 months) 2007 mean Pacific water inflow at Bering Strait is 1.2 Sv,which is the highest in the past three decades of the simulation and is 20%higher than the recent average.Particularly ,the Pacific water inflow in September 2007 is about 0.5 Sv or 50%above the 2000-2006 average.The strengthened warm Pacific water inflow carries an additional 1.0×10~(20) Joules of heat into the Arctic,enough to melt an additional 0.5 m of ice over the whole Chukchi Sea.In the model the extra summer oceanic heat brought in by the Pacific water mainly stays in the Chukchi and Beaufort region,contributing to the warming of surface waters in that region.The heat is in constant contact with the ice cover in the region in July through September.Thus the Pacific water plays a role in ice melting in the Chukchi and Beaufort region all summer long in 2007,likely contributing to up to 0.5 m per month additional ice melting in some area of that region .  相似文献   

18.
The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been regarded as a powerful measure for the ecological restoration in the Loess Plateau and the upper reaches of the Yangtze River. “Relieving and de-farming” (RD) and“rebuilding terrace and de-farming” (RTD) are two more mature ones among various de-farming modes. Taking the loess hilly-gully region as a case, this paper summarized the basic characteristics of RD and RTD modes, calculated the sizes of de-farming slope farmland, rebuilt terraces, enlarged garden plots and restored vegetation, and compared the differences of two modes in terms of de-farming area, ecological reestablishment index, investment demand amount and benefits. The results showed that RTD mode has many advantages, including suitable investment, sufficient grain supply and great benefits, and will be the best ecological reestablishment mode in the loess hilly-gully region, and RD mode which is being carried out in this region should be replaced by RTD mode as soon as possible.  相似文献   

19.
Zhou  Kan  Yin  Yue  Li  Hui  Shen  Yuming 《地理学报(英文版)》2021,31(1):91-110
Environmental stress is used as an indicator of the overall pressure on regional environmental systems caused by the output of various pollutants as a result of human activities. Based on the pollutant emissions and socioeconomic databases of the counties in Beijing–Tianjin–Hebei region, this paper comprehensively calculates the environmental stress index(ESI) for the urban agglomeration using the entropy weight method(EWM) at the county scale and analyzes the spatiotemporal patterns and the differences among the four types of major functional zones(MFZ) for the period 2012–2016. In addition, the socioeconomic driving forces of environmental stress are quantitatively estimated using the geographically weighted regression(GWR) method based on the STIRPAT model framework. The results show that:(1) The level of environmental stress in the Beijing–Tianjin–Hebei region was significantly alleviated during that time period, with a decrease in ESI of 54.68% by 2016. This decrease was most significant in Beijing, Tangshan, Tianjin, Shijiazhuang, and other central urban areas, as well as the Binhai New Area. The level of environmental stress in counties decreased gradually from the central urban areas to the suburban areas, and the high-level stress counties were eliminated by 2016.(2) The spatial spillover effect of environmental stress increased further at the county scale from 2012 to 2016, and spatial locking and path dependence emerged in the cities of Tangshan and Tianjin.(3) Urbanized zones(development-optimized and development-prioritized zones) were the major areas bearing environmental pollution in the Beijing–Tianjin–Hebei region in that time period. The ESI accounted for 65.98% of the whole region, where there was a need to focus on the prevention and control of environmental pollution.(4) The driving factors of environmental stress at the county scale included population size and the level of economic development. In addition, the technical capacity of environmental waste disposal, the intensity of agricultural production input, the intensity of territorial development, and the level of urbanization also had a certain degree of influence.(5) There was spatial heterogeneity in the effects of the various driving factors on the level of environmental stress. Thus, it was necessary to adopt differentiated environmental governance and reduction countermeasures in respect of emission sources, according to the intensity and spatiotemporal differences in the driving forces in order to improve the accuracy and adaptability of environmental collaborative control in the Beijing–Tianjin–Hebei region.  相似文献   

20.
On coordinated development of oasis and environment in arid area   总被引:1,自引:0,他引:1  
1 Formation and evolution of oasisBoth physical environment and human activities influence the formation and evolution of oasis. Natural oasis is a kind of ecological landscape formed mainly by water without human intervention. Its prosperity and adversity primarily depends on the flow direction and discharge of a river. With the increment of intensity of human activities, however, great changes have taken place in oasis in arid area. The evolution of oasis has been transformed from the contr…  相似文献   

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