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1.
基于垂直带谱的南北过渡带1:5万植被类型图遥感制图研究——以太白山为例 总被引：1，自引：1，他引：1
The compilation of 1:250,000 vegetation type map in the North-South transitional zone and 1:50,000 vegetation type maps in typical mountainous areas is one of the main tasks of Integrated Scientific Investigation of the North-South Transitional Zone of China.In the past,vegetation type maps were compiled by a large number of ground field surveys.Although the field survey method is accurate,it is not only time-consuming,but also only covers a small area due to the limitations of physical environment conditions.Remote sensing data can make up for the limitation of field survey because of its full coverage.However,there are still some difficulties and bottlenecks in the extraction of remote sensing information of vegetation types,especially in the automatic extraction.As an example of the compilation of 1:50,000 vegetation type map,this paper explores and studies the remote sensing extraction and mapping methods of vegetation type with medium and large scales based on mountain altitudinal belts of Taibai Mountain,using multi-temporal high resolution remote sensing data,ground survey data,previous vegetation type map and forest survey data.The results show that:1)mountain altitudinal belts can effectively support remote sensing classification and mapping of 1:50,000 vegetation type map in mountain areas.Terrain constraint factors with mountain altitudinal belt information can be generated by mountain altitudinal belts and 1:10,000 Digital Surface Model(DSM)data of Taibai Mountain.Combining the terrain constraint factors with multi-temporal and high-resolution remote sensing data,ground survey data and previous small-scale vegetation type map data,the vegetation types at all levels can be extracted effectively.2)The basic remote sensing interpretation and mapping process for typical mountains is interpretation of vegetation type-groups→interpretation of vegetation formation groups,formations and subformations→interpretation and classification of vegetation types&subtypes,which is a combination method of top-down method and bottom-up method,not the top-down or the bottom-up classification according to the level of mapping units.The results of this study provide a demonstration and scientific basis for the compilation of large and medium scale vegetation type maps. 相似文献
2.
Demand for food plays an important role in the adjustment of prices for agricultural products and for adjusting agricultural structure.By using the extended linear expenditure system(ELES),we analyzed the food consumption structure of rural residents in the Ganzhou district of Zhangye city,and determined the basic food-consumption demand,the marginal propensity of consumption,the income elasticities of demand,and the own-price and cross-price elasticities of local rural residents,all of which illustrate the influencing factors on food consumption of rural residents and for forecasting the food-consumption structure.Those analyses show the following:the rural residents’ expenditure on household basic food consumption reaches about 7,050.35 Yuan;the marginal propensities of consumption of fruits and vegetables are relatively high(0.062 and 0.106,respectively),followed by meat(0.044);the demands for various foods are increasing as income increases,with the largest income elasticity of demand corresponding to fruits(1.354) and the lowest to cereal(0.310);fruits and vegetables have relatively high own-price elasticities(respectively-0.879 and-0.442),with the cereal having the lowest one(-0.184).An increase in cereal prices would greatly affect demand for other products;with the rising size of rural households,the consumption for meat is decreasing whereas it is increasing for cereal.The improvement of household education levels will lead to the increase of fruit consumption(E = 0.297),which indicates that people will pay more attention to diet and nutrition structure with the improvement of education.Further,although the amount of cereal expenditure is continually growing,the share will be declining with the increase of household income in 2006-2012.For all these reasons,therefore,the government should encourage the cultivation of economic crops and guide the development of stockbreeding to ensure the stability of cereal output.In order to attain the balance between supply and demand,it is important to rationally a 相似文献
3.
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
4.
Urban resilience is an emerging research topic of urban studies, and its essence is described by the ability of cities to resist, recover, and adapt to uncertain disturbances. This paper constructs a "Size-Density-Morphology" urban ecological resilience evaluation system, uses a coupling coordination degree model to measure the degree of coupling coordination between urbanization and ecological resilience in the Pearl River Delta from 2000 to 2015, and conducts an in-depth discussion on its spatiotemporal characteristics. The results show the following.(1) From 2000 to 2015, the urbanization level of cities in the study area generally increased while the level of ecological resilience declined. The coupling coordination degree between the two systems decreased from basic coordination to basic imbalance.(2) In terms of spatial distribution, the coupling coordination degree between urbanization and ecological resilience of cities presented a circular pattern that centered on the cities at the estuary of the Pearl River and increased toward the periphery.(3) Ecological resilience sub-systems played variable roles in the coupling coordination between urbanization and ecological resilience. Specifically, size resilience mainly played a reverse blocking role;the influence of morphology resilience was generally positive and continued to increase over time;the effect of density resilience was positive and continued to decline and further became negative after falling below zero. The main pathways for achieving coordinated and sustainable development of future urbanization and ecological resilience in the Pearl River Delta include: leading the coordinated development of regions with new urbanization, improving ecological resilience by strictly observing the three areas and three lines, adapting to ecological carrying capacity, and rationally arranging urban green spaces. 相似文献
5.
Climate change resulting from CO_2 emissions has become an important global environmental issue in recent years.Improving carbon emission performance is one way to reduce carbon emissions.Although carbon emission performance has been discussed at the national and industrial levels,city-level studies are lacking due to the limited availability of statistics on energy consumption.In this study,based on city-level remote sensing data on carbon emissions in China from 1992–2013,we used the slacks-based measure of super-efficiency to evaluate urban carbon emission performance.The traditional Markov probability transfer matrix and spatial Markov probability transfer matrix were constructed to explore the spatiotemporal evolution of urban carbon emission performance in China for the first time and predict long-term trends in carbon emission performance.The results show that urban carbon emission performance in China steadily increased during the study period with some fluctuations.However,the overall level of carbon emission performance remains low,indicating great potential for improvements in energy conservation and emission reduction.The spatial pattern of urban carbon emission performance in China can be described as"high in the south and low in the north,"and significant differences in carbon emission performance were found between cities.The spatial Markov probabilistic transfer matrix results indicate that the transfer of carbon emission performance in Chinese cities is stable,resulting in a"club convergence"phenomenon.Furthermore,neighborhood backgrounds play an important role in the transfer between carbon emission performance types.Based on the prediction of long-term trends in carbon emission performance,carbon emission performance is expected to improve gradually over time.Therefore,China should continue to strengthen research and development aimed at improving urban carbon emission performance and achieving the national energy conservation and emission reduction goals.Meanwhile,neighboring cities with different neighborhood backgrounds should pursue cooperative economic strategies that balance economic growth,energy conservation,and emission reductions to realize low-carbon construction and sustainable development. 相似文献
6.
The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence, it poses a certain threat to social development. Identifying the characteristics of and regions vulnerable to climate change is significantly important for formulating adaptive countermeasures. However, with regard to the Yangtze River Watershed, there is currently a lack of research on these aspects from the perspective of natural and anthropogenic factors. To address this issue, in this study, based on the temperature and precipitation records from 717 meteorological stations, the RClim Dex and random forest models were used to assess the spatiotemporal characteristics of climate change and identify mainly the natural and anthropogenic factors influencing climate change hotspots in the Yangtze River Watershed for the period 1958-2017. The results indicated a significant increasing trend in temperature, a trend of wet and dry polarization in the annual precipitation, and that the number of temperature indices with significant variations was 2.8 times greater than that of precipitation indices. Significant differences were also noted in the responses of the climate change characteristics of the sub-basins to anthropogenic and natural factors;the delta plain of the Yangtze River estuary exhibited the most significant climate changes, where 88.89% of the extreme climate indices varied considerably. Furthermore, the characteristics that were similar among the identified hotpots, including human activities(higher Gross Domestic Product and construction land proportions) and natural factors(high altitudes and large proportions of grassland and water bodies), were positively correlated with the rapid climate warming. 相似文献
7.
《地理学报》1947,(Z1)
1. Location and Historical Development Chengtu, the capital city of western Szechwan, is located on the lower part of the Min and Tu alluvial fan (Fig.1) which has an area of about 6,000 sq.km., and is the most fertile irrigated fields of the western China. The autbor discusses the location and site of the city to compare with other cities on the alluvial fan, and finds that the selection and development of Chengtu as a capital city is due chiefly to the reason that it is situated at the terminus point o... 相似文献
8.
中国山地范围界定的初步意见 总被引：8，自引：1，他引：7
中国山地的范围一直缺乏可操作的、准确的量化方法,从而导致对山地及其内部资源、环境、人口和发展问题认识的不全面.同时,准确界定山地范围是实施数字山地战略的一项基础性工作.在前人研究的基础上,采用两种方案确定中国山地范围.方案一:将满足以下两种情况的国土界定为山地,1)海拔≥3 000 m;2)海拔≥1300～3 000 m,同时相对高差>200 m或坡度>25°.根据此标准计算,中国山地面积为4 000 265 km2,占中国陆地面积的41.67%.方案二:根据UNEP-WCMC的标准,将满足下述情况的国土定义为山地,1)海拔≥2 500 m;2)海拔≥1 500～2 500 m,坡度≥2°;3)海拔≥1 000～1 500 m,坡度≥5°或相对高差≥300 m;4)海拔≥300～1 000 m,相对高差≥300 m.根据此标准计算,中国山地面积为4 426 130 km2占中国陆地面积的46.11%.按两种方法计算所得的分省山地面积中,前5名都是西藏、青海、新疆、四川和云南.将两种方案计算的山地面积按高程划分为六级:①300～1 000 m(含300 m),②1 000～1 500 m(含1 000 m),③1 500～2 500 m(含1 500 m),④2 500～3 500 m(含2 500 m),⑤3 500～4 500 m(含3 500 m),⑥≥4 500 m.根据两种方案的定义,海拔3 500 m以上的山地面积相等;除了方案-在300～1 000 m间山地较方案二多324 508 km2外,其余几个级别山地的面积均为方案二大于方案-的山地面积,其中2 500～3 500 m间多133 432 km2,1 500～2 500 m间多336 186 km2,1 000～1 500 m间多282 273 km2. 相似文献
9.
The concept of‘Beautiful China'is a new goal of ecological construction in the new era of socialism and aims to meet the needs of people as they strive for a better life.National land spatial planning is one major component of the Chinese state's overall planning for various spatial types.The concept of‘Beautiful China'is thus a leading goal of Chinese development in the second centenary.The background of this concept aims for‘ecological beauty'as well as the combined beauty of‘economy-politics-culture-society-ecology.'The construction of‘Beautiful China'therefore necessitates a differentiated evaluation index system that is built on the basis of local conditions.This concept is intimately related to land spatial planning and the idea of Beautiful China guides an important direction for this planning which itself provides an important mechanism and spatial guarantee for construction.The establishment of land spatial planning nevertheless needs to strengthen further discussion of the regional system of human-land relationship,point axis system,main functional division,sustainable development,resources and environmental carrying capacity as well as new urbanization,and the rural multi-system.The aim of this paper is to summarize current thinking in land spatial planning,scientifically analyze the natural geographical conditions,the socioeconomic development,the interrelationship of the land space,plan the goal,vision and path of land space,encourage the public to participate in and carry out dynamic evaluation,build an intelligent system platform for land and spatial planning to realize the goal of‘Beautiful China'from a geographical perspective.And they can also present key ideas relating to the compilation and implementation of land spatial planning. 相似文献
10.
中国欠发达地区可持续减贫与绿色发展研究 总被引：2，自引：2，他引：0
In 2020, the decisive victory of building a moderately well-off society in all aspects means that absolute poverty in rural China has been completely eliminated. Consolidating and expanding the achievements of poverty alleviation and establishing a long-term mechanism to solve relative poverty have become key issues in high-quality development of underdeveloped areas. In this study, human-earth system is employed to analyze the element composition, structural organization and functional state of underdeveloped areas. The results show that poverty in underdeveloped areas stems from the lack of the coupling and coordinating mechanism among human, economic, resource and environmental elements, which is not conducive to transforming the ecological advantages into the advantages of regional development. In the antipoverty stage, underdeveloped areas innovate the human-earth coupling and coordinating mechanism through a series of targeted measures, promote the organic combination of poverty alleviation, ecological conservation and sustainable development, and boost the transformation of regional development and the increase of farmers’ incomes. Focusing on the 14 th Five-year Plan(2021–2025) and the long-term goal of 2035, governments in underdeveloped areas should make full use of the policy support to explore scientific methods of modern governance and sustainable development. In particular, it is necessary to practice the concept that "clear waters and lush mountains are invaluable assets" and take the road of the ecologicalization of industry and the industrialization of ecology by establishing a policy system of "green land", "green people", "green industry" and "green right", thus building an endogenous growth mechanism of sustainable poverty alleviation and green development in China’s underdeveloped areas. 相似文献
11.
Based on the acquaintance of the regional background of urban-rural transforma-tional development and investigations on the spot, this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade, with the aid of GIS technology. Conclusions of the research are summarized as follows: (1) the arable land had been continuously de-creasing from 1996 to 2005, with a loss of 1,708,700 hm2 and an average decrement of 170,900 hm2 per year; (2) land for construction increased 1,373,700 hm2, with an average increment of 153,200 hm2 per year; (3) total area of encroachment on arable land for con-struction between 1996 and 2005 was 1,053,100 hm2, accounting for 34.03% of the arable land loss in the same period, the percentages of which used for industrial land (INL), trans-portation land (TRL), rural construction land (RUL) and town construction land (TOL) are 45.03%, 15.8%, 15.47% and 11.5%, respectively; and (4) the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation’s macroscopic land-use policies and development level of regional economy. The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures, rural urbanization and expansion of rural set-tlements in the eastern coastal area, and therefore were the primary driving forces of land-use conversion. 相似文献
12.
Based on the acquaintance of the regional background of urban-rural transformational development and investigations on the spot,this paper discusses the holistic situation, dominant factors and mechanism of arable land loss and land for construction occupation in the coastal area of China over the last decade,with the aid of GIS technology.Conclusions of the research are summarized as follows：（1）the arable land had been continuously decreasing from 1996 to 2005,with a loss of 1,708,700 hm^2 and an average decrement of 170,900 hm^2 per year;（2）land for construction increased 1,373,700 hm^2 ,with an average increment of 153,200 hm^2 per year;（3）total area of encroachment on arable land for construction between 1996 and 2005 was 1,053,100 hm^2 ,accounting for 34.03%of the arable land loss in the same period,the percentages of which used for industrial land（INL）,transportation land（TRL）,rural construction land（RUL）and town construction land（TOL）are 45.03%,15.8%,15.47%and 11.5%,respectively;and（4）the fluctuation of the increase of construction land and encroachment on arable land in the area were deeply influenced by the nation＇s macroscopic land-use policies and development level of regional economy.The growth of population and advancement of technology promoted the rapid industrialization, construction of transportation infrastructures,rural urbanization and expansion of rural settlements in the eastern coastal area,and therefore were the primary driving forces of land-use conversion. 相似文献
13.
Based on TM image data and other survey materials, this paper analyzed the spatiotemporal patterns of land use change in the Bohai Rim during 1985–2005. The findings of this study are summarized as follows: (1) Land use pattern changed dramatically during 1985–2005. Industrial and residential land in urban and rural areas increased by 643,946 hm2, of which urban construction land had the largest and fastest increase of 294,953 hm2 at an annual rate of 3.72%. (2) The outward migration of rural population did not prevent the expansion of residential land in rural areas by 184,869 hm2. This increase reveals that construction of rural residences makes seriously wasteful and inefficient use of land. (3) Arable land, woodland and grassland decreased at a rate of –0.02%, –0.12% and –1.32% annually, while unused land shrank by 157,444 hm2 at an annual rate of –1.69%. (4) The change of land use types showed marked fluctuations over the two stages (1985–1995 and 1995–2005). In particular, arable land, woodland and unused land experienced an inversed trend of change. (5) There was a significant interaction between arable land and woodland. Industrial construction land in urban and rural areas showed a net trend of increase during the earlier period, but only adjustment to its internal structure during the second period. The loss of arable land to the construction of factories, mines and residences took place mainly in the fringe areas of large and medium-sized cities, along the routes of major roads, as well as in the economically developed coastal areas in the east. Such changes are closely related to the spatial differentiation of the level of urbanization and industrialization in the region. 相似文献
14.
15.
北京丰台区农村居住用地变化及与人口相关模型 总被引：12，自引：1，他引：12
采用GIS技术和统计分析技术，基于1984年，1992年，1996年和1999年4期土地利用图件和数据，分析了1984－1999年期间北京丰台区农村居住用地变化过程及地域分异特征；提出并应用特征均值探讨了农村人均居住用地和人居密度变化的过程和趋势，以行政村为基本单元，利用1999年农村居住用地数据与对应的农村人口数据建立了表达式为Sv=11.324e^0.0006pv的农村居住用地与人口相关模型；用1992年数据对模型进行检验和误差分析的结果表明，模型适用地域为北京近郊且不邻近卫星城镇的农村区。 相似文献
16.
Based on TM image data and other survey materials, this paper analyzed the spatiotemporal patterns of land use change in the
Bohai Rim during 1985–2005. The findings of this study are summarized as follows: (1) Land use pattern changed dramatically
during 1985–2005. Industrial and residential land in urban and rural areas increased by 643,946 hm2, of which urban construction land had the largest and fastest increase of 294,953 hm2 at an annual rate of 3.72%. (2) The outward migration of rural population did not prevent the expansion of residential land
in rural areas by 184,869 hm2. This increase reveals that construction of rural residences makes seriously wasteful and inefficient use of land. (3) Arable
land, woodland and grassland decreased at a rate of −0.02%, −0.12% and −1.32% annually, while unused land shrank by 157,444
hm2 at an annual rate of −1.69%. (4) The change of land use types showed marked fluctuations over the two stages (1985–1995 and
1995–2005). In particular, arable land, woodland and unused land experienced an inversed trend of change. (5) There was a
significant interaction between arable land and woodland. Industrial construction land in urban and rural areas showed a net
trend of increase during the earlier period, but only adjustment to its internal structure during the second period. The loss
of arable land to the construction of factories, mines and residences took place mainly in the fringe areas of large and medium-sized
cities, along the routes of major roads, as well as in the economically developed coastal areas in the east. Such changes
are closely related to the spatial differentiation of the level of urbanization and industrialization in the region. 相似文献
17.
中国东部沿海地区乡村转型发展与新农村建设 总被引：105，自引：16，他引：89
1978 年改革开放以来, 中国东部沿海地区工业化、城市化的快速发展, 深刻地改变着广大农村地区, 促使农村产业结构、就业结构与农业生产方式等发生巨大变化, 乡村发展步入转型升级的新阶段。1978-2005 年, 沿海地区第一产业比重由23.3%降为7.9%, 第三产业比重由19.8%升为40.5%, 农业劳动力比重则由90.8%降为47.9%。模拟分析表明, 沿海地区 农业产值与农业就业份额仍将持续下降, 2010 年、2020 年农业产值比重将降为8.0%和 6.0%, 农业劳动力比重将降为44.5%和32.2%。1990-2005 年, 沿海地区劳耕弹性系数为1.84, 反映了农业劳动力的转移远快于耕地面积的减少, 农业劳动力效益在稳步提高。同期, 乡村人口由3.06 亿人降为2.19 亿人, 而农村人均居住用地规模却在增大, 未能实现农村人口 转移与农村居民点的减少相挂钩。沿海地区新农村建设须遵循乡村转型发展规律, 重在科学规划、分区推进, 通过优化城乡用地、发展现代农业和农村特色经济, 提升农村生产力, 促进沿海城乡互动与协调发展。 相似文献
18.
基于地学信息图谱的土地利用动态变化研究——以山东省龙口市为例 总被引：1，自引：0，他引：1
阐述了地学信息图谱的内涵及其概念模式.选择山东省龙口市为例,在遥感和地理信息系统技术支持下,利用2002年数字遥感图像和1996年土地利用图及其自然和社会经济统计数据,建立了龙口市土地利用动态变化信息图谱,并根据图谱从空间和时间两方面分析龙口市土地利用动态演变过程,最后结合马尔科夫模型对其未来的演变趋势进行动态预测.研究表明:自1996年以来,龙口市土地利用发生了大幅度变化,耕地面积减少5 383.48 hm2,园地和建设用地面积各增加33 729.62 hm2和2319.91 hm2;同时土地利用结构发生明显变化,主要表现在耕地和园地之间的转化,耕地和园地向建设用地的转化.预测表明:在未来的几十年内,耕地面积仍将继续减少,建设用地面积还会逐年增加,园地仍为该市的主要用地类型. 相似文献
19.
龙口市海岸带土地利用动态变化分析 总被引：13，自引：0，他引：13
利用多期遥感数据,采用目视解译和人机交互计算机分类技术提取1984至2004年间龙口市海岸带土地利用信息,从土地利用总量变化、土地利用变化速度、土地利用类型之间的相互转化、土地利用类型变化的海岸区位效应等方面分析龙口市海岸带动态变化特点。研究结果表明,20年间龙口市海岸带一半以上的土地类型发生了变化,变化速度逐年增加,后期明显大于前期;转化方向上主要表现在耕地向园地的转化,其次是耕地、园地、林地向建设用地的转化;变化的区位特征是距海越近,海岸带特征地类的变化越明显,反之,距海越远,内陆土地利用变化的特点表现得越突出。 相似文献
20.
北部湾沿海地区土地利用动态模拟与水源涵养服务能力估算——以广西钦州市为例 总被引：2，自引：0，他引：2
分析北部湾沿海地区广西钦州市土地利用格局及未来变化趋势,为开展该地区土地利用规划和生态服务价值中的水源涵养服务能力估算提供决策依据.以2000年、2010年的TM遥感影像以及各种驱动因子数据为基础,耦合Binary Logistic及CA-Markov模型对研究区2020年的土地利用格局进行模拟,并对研究区的水源涵养服务能力进行估算.结果表明：（1） 2000～2010年各种土地利用类型的转化强度大且比较复杂,尤以耕地、林地和水域之间的流动最为显著,建设占用耕地和林地的面积高达2 003.31 hm2;（2）由Binary Logistic逻辑斯蒂回归方程所得出的各种土地利用类型ROC拟合值中最小为0.686,最大达到0.952,模拟效果良好;（3）预测年2020年建设用地增加的区域主要集中在钦州市钦南区的市区周边,向东方向扩展,变化比较剧烈的地方主要是钦州港区和研究区域的北部;（4）单位面积水源涵养能力的排序依次为：水域＞林地＞草地＞耕地＞建设用地＞未利用地,3个年份的水源涵养服务能力在空间上均呈现出“东南部高西北部低,中心地带持续衰减”的趋势. 相似文献