GIS Spatial Analysis Techniques Research Articles

Analysis of spatial-temporal differentiation and influence factors of construction land expansion of the urban agglomeration in central Yunnan

This paper takes the plateau mountain city: the urban agglomeration in central Yunnan as the research area, 2000-2015 as the research period, and measure and analyze the spatio-temporal differentiation of construction land expansion in the urban agglomeration based on the calculation of kernel density. Use the spatial autocorrelation model to analyze the spatial autocorrelation patterns of construction land on the 1 km × 1 km grid scale, and then use the GIS spatial analysis technique to study the local aggregation area at the p<0.05 significance level of the construction land in relation to natural and social driving factors. The result shows that the growth and distribution of urban construction land in this urban agglomeration is affected by natural social factors and land policies, and the area of construction land is growing rapidly. The areas with large distribution density of construction land at four time points are mainly located in flat dam area in the central and eastern part of the urban agglomeration, and mountain in the northern part. The spatial distribution of construction land in this urban agglomeration from 2000 to 2015 is mainly represented by two patterns: high-high aggregation and low-low aggregation. The topographical features dominated by plateau mountains affect the local spatial clustering of the construction land. At 4 time points, the elevation is 1000∼3000 m, the slope is between 2°-25° and the sunny slope area is the area with the largest distribution and the most concentrated area of the construction area. The farther away from the water system and the road, the local space gathering area of construction land is decreasing.

Contribution of ecological policies to vegetation restoration: A case study from Wuqi County in Shaanxi Province, China

Ecological policies can regulate and modify human activities, affecting land use, and eventually, regional vegetative cover. The impact of these policies on vegetation cover is mediated by natural factors as well as social and economic statuses. The former contains meteorological and topographical indicates, and the latter includes population density, per capita cultivated land, transportation convenience, etc. The chosen study area for this study was Wuqi County, situated in the northern Shaanxi Province of China. Using remote sensing and GIS spatial analysis techniques, land use and vegetation index data of Wuqi from 1995 to 2011 were obtained along with topographical, meteorological, and socio-economic data. Further, the vector and grid data were pooled using a village as a unit, to establish a spatial database in ArcGIS 10.2. Multiple regression models, including a geographically weighted model, along with spatial analysis, were applied to calculate the contribution of ecological policies to the vegetation restoration in the study area under the constraint of resource endowment, particularly ecological policies in terms of restoration of ecological land from cultivated land, conservation of forests and pastures. The results of spatial overlay showed an interesting spatial coupling between changes in land use and improvement in vegetation index. The results of the regression models could reveal the comprehensive and quantitative contribution of ecological policies to vegetation restoration since control variables such as resource endowments were included. Moreover, analyses based on both classical regression and geographically weighted regression indicated that land use has considerable influence on vegetation restoration, while the results of the latter showed a higher significance level and could reveal the spatial differences due to policy effects.

Predicting the potential distribution of dominant species of the coastal wetland in the Yellow River Delta, China using MaxEnt model

Soil and vegetation community were investigated using the method of kilometer grid sampling. In addition, using the maximum entropy (MaxEnt) and the GIS spatial analysis technique, the potential distribution of dominant species in the Yellow River Delta and their major environmental variables and ecological parameters were quantitatively analyzed. The results showed that the dominant species of the coastal wetland were Tamarix chinensis, Phragmites australis and Suaeda salsa in the Yellow River Delta. Among the environmental variables, six variables were significant contributors to the potential distribution model of T. chinensis: NO3--N, salt, slope, Mg, altitude and NH4+-N. The environmental variables influencing the distribution of P. australis were NO3--N, salt, TP, pH, altitude and NH4+-N. NO3--N, salt and NH4+-N were the significant factors determining the potential distribution of S. salsa. The probability of presence of dominant species of the coastal wetland in the Yellow River Delta was positively correlated with salt, but it was negatively correlated with the other major environmental variables. The model predicted that the core potential distribution of dominant species in the Yellow River Delta was mainly in the coastal areas. In addition, P. australis had a wider range of distribution, compared with T. chinensis and S. salsa.

基于PSR框架的内蒙古自治区土壤保持服务分区

PDF HTML阅读 XML下载 导出引用 引用提醒 基于PSR框架的内蒙古自治区土壤保持服务分区 DOI: 10.5846/stxb201702200273 作者: 作者单位: 北京大学,北京大学,北京大学,北京大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国土资源部公益性行业科研专项经费课题（201511001-01） Soil conservation service zoning in the Inner Mongolia Autonomous Region based on PSR framework Author: Affiliation: Peking University,Peking University,Peking University,Peking University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤侵蚀是中国北方重要的生态问题，内蒙古自治区位于干旱半干旱地区，是中国北方典型的土壤侵蚀区。针对以往生态功能分区分析框架复杂多样、权重设定人为主观等问题，以内蒙古自治区为例，基于压力-状态-响应系统分析框架，从气候背景-土壤保持-植被条件三方面构建指标体系，运用自组织特征映射（SOFM）神经网络和GIS空间分析技术，以1280个小流域为基本单元进行土壤保持服务分区，按照分区单元的聚集度对多种方案进行优选，并依据区域共轭性原则最终将研究区划分为3个土壤保持服务区和11个土壤保持服务亚区。 Abstract:Soil erosion has been a critical ecological issue in northern China. Inner Mongolia Autonomous Region is located in the arid and semi-arid area, which is a typical soil erosion area in northern China. Based on the analytical framework of pressure-state-response (PSR), this study takes the Inner Mongolia Autonomous Region as the study area, and constructs the index system from three aspects: climatic background, soil conservation, and vegetation condition. It aims at addressing the remaining issue of complexity and subjectiveness in weigh specification towards ecological function zoning in the previous studies. In the study, self-organizing feature map (SOFM) neural network and GIS spatial analysis technique were applied to carry out the soil conservation service zoning with the 1280 small watersheds as the basic unit and the schemes were optimized according to the aggregation degree of the zoning units. The Inner Mongolia Autonomous Region was divided into three ecological functional zones and eleven sub-zones based on the principle of regional conjugation. The three ecological functional zones include Soil Conservation Services Protection Area, Soil Conservation Services Controlling Area, and Soil Conservation Services Rehabilitation Area. According to the characteristics of zoning, the results clearly indicate the zonal distribution of climatic background, soil conservation service and vegetation condition in Inner Mongolia, and quantify the characteristics and spatial differences of the ecological functions at watershed scale more comprehensively. The result of the optimal soil conservation service zoning was compared to the annual average temperature contours and annual precipitation contours in Inner Mongolia. It shows that the ecological function zoning results obtained by SOFM neural network model were in good agreement with the spatial patterns of basic ecological elements. The zoning scheme indicates a significant gradient and is consistent with changes in temperature and precipitation. 参考文献 相似文献 引证文献

Assessing environmental justice through potential exposure to air pollution: A socio-spatial analysis in Madrid and Barcelona, Spain

The concept of environmental justice (EJ) has recently gained currency, both as a factor for and a goal of sustainable development. Its implementation in practice implies establishing current environmental injustice patterns and analysing planning policies, with the aim to reduce socio-demographic inequalities in the negative environmental impact borne by different population groups. This paper proposes a method to assess differential exposure to excessive pollution levels by socio-demographic groups in intra-urban spaces.The approach developed in this paper is based upon GIS and quantitative spatial analysis techniques. It incorporates the idea of an ‘environmental justice weighting scale’ for policy-making, using normative pollution thresholds to measure inequalities more objectively and consistently. Spain’s two largest cities, Madrid and Barcelona, have been chosen as case-studies, taking nitrogen dioxide as the pollutant, and the geographic distribution of six vulnerable population groups (children, elderly people and international immigrants) in the year 2010. The results reveal that a large part of these groups suffer exposure to air pollution exceeding the maximum permitted levels disproportionately, which would imply a case of environmental injustice.

基于GIS的湖南省山洪沟提取技术及其应用

本文基于GIS空间分析技术进行流域信息分析，结合坡度、地形起伏度等地形特征，利用逆流原理对湖南省山洪沟边界信息进行提取，结果表明：1) 湖南省山洪沟多分布在湖南省西北部、南部和中部山区。与降水分布进行对比，发现这些地区降水分布相对集中，且出现强降水的概率较大，出现山洪灾害的风险较高。2) 对山洪沟预测指标进行等级分级，用不同等级值反映了山洪灾害发生的概率，可以看出提取的山洪沟位置信息与实际发生山洪灾害的位置有很好的对应关系。说明山洪沟的分布能在一定程度内反映出山洪灾害的发生地点。3) GIS提取结果与历史普查的山洪灾害发生区域进行叠加分析，相似度较高，较好的验证了山洪沟提取的可靠性。 In this paper, GIS spatial analysis technique is based on watershed information analysis, combined with slope, terrain ruggedness, and other terrain features, to extract flash floods ditch of Hunan. The results showed that: 1) Flash floods ditches are located in mountainous areas of northwestern, southern and central in Hunan Province. Compared with the distribution of precipitation, rainfall distribution is concentrated in these areas, and both the probability of heavy precipitation and risk of flood disasters are higher. 2) Used different levels of value to reflect the probability of flash floods disasters, we can see that it has a good relationship between flash flood position by extracted and the actual location of flood disasters. To some extent, the distribution of flash floods ditch also has been reflected the occurrence of flood disasters in place. 3) The results can reflect the Flash floods ditch extraction reliability compared with the history fact of flash flood disasters.

The Potential Geographic Analysis and Prediction ofAcertataricumsubsp. Ginnalain China

The Potential Geographic Analysis and Prediction of Acer tataricum subsp. Ginnala in China As a versatile and highly ornamental tree species, Acer tataricum subsp. ginnala is widely distributed in the contemporary ages (1950- 2000). Predicting its potential geographic distribution not only has great significance for its protection, but also provides theoretical support for forecasting other endangered species geographic distribution. In this study, MaxEnt model combined the GIS spatial analysis techniques were used to predict the potential geographic distribution of Acer tataricum subsp. ginnala from the 2030s to the 2070s. The reasons for the changes of geographic distribution were analyzed based on the future climate characteristics of China. The present results showed that Acer tataricum subsp. ginnala had different levels of distribution in China from 2030s to 2070s. The geographic distribution of Acer tataricum subsp. ginnala was mainly in the Northeast and North China. However, the mainly geographic distribution of Acer tataricum subsp. ginnala had changed because of the effects of temperature, precipitation and other climatic factors. In special, the distribution was moved to eastern parts of Shandong, parts of Hubei, the bordering parts of Jiangsu and Anhui provinces. Acer tataricum subsp. ginnala suitable areas in the country had shown a obviously reduction trend with the advance of years, And the future climate of China will be not conducive to the growth of Acer tataricum subsp. ginnala. The information got in this study will be usefull for the Acer tataricum subsp. ginnala protection in China...

Land suitability assessment for post-earthquake reconstruction: A case study of Lushan in Sichuan, China

Land suitability assessment (LSA) is one of the key processes of land-use planning. Given its particularity of land suitability assessment for post-earthquake reconstruction, this paper takes into account geological conditions, risk of disasters, water and land resources conditions, and eco-environmental suitability and emphasizes safety factor in the assessment. Taking the April 20, 2013 Mw 6.6 Lushan earthquake as a case, this assessment establishes factors system, uses GIS spatial analysis techniques and data of geology, topography, resources, and eco-environment to evaluate the land suitability for reconstruction. The results show that: (1) the spatial characteristics of land suitability for reconstruction at grid scale and administrative scale manifest that most of the piedmont plains in the east are suitable for large-scale population aggregation, industrialization, and urbanization development; and (2) for the six hard-hit counties, Mingshan is the preferred region for large-scale post-earthquake reconstruction due to its high construction index and suitable land per capita, and some plots of land in the valleys could be selected for in-situ small-scale reconstruction in Lushan. The land suitability assessment for post-earthquake reconstruction would be significant to making sound reconstruction planning for achieving sustainable regional development in the Mw 6.6 Lushan earthquake stricken area. This study could be used as a reference for the regions with similar events.

Spatial Variation of Soil Available Phosphorous in the Dal Lake Catchment of Lesser Himalayas

The study attempts to evaluate the spatial pattern of soil available phosphorus, and its availability with respect to various factors including elevation, slope and landuse using statistical methods and GIS spatial analysis techniques. The results showed that the Ordinary Kriging Spherical method performed the best in the prediction of soil available phosphorus in the Dal Lake catchment. The spatial variation of soil available phosphorus was high in Dal Lake catchment and the upstream regions around Dal Lake, including the north of Dal Lake, had the highest soil available phosphorus content. The mean and standard deviation of soil available phosphorus content gradually decreased as the slope increased. The cultivated land comprised 24.36% of the catchment and out of that land 50.81% belonged to the medium to very high SAP level classes, and it played a major role in SAP availability within the catchment and a potential source of phosphorus to Dal Lake resulting in eutrophication. Among land use types, paddy fields have some of the highest maximum values and variation of coefficients. Sub watershed scale soil available phosphorus was significantly affected by elevation, slope and landuse and was decided by not only these environmental factors but also some other factors such as artificial phosphorus fertilizer application.

Geological risk assessment for the rapid development area of the Erhai Basin

For low-slope hilly land development to have more new land space in a watershed, it is particularly important that to coordinate the sharply increasing conflicts between mountainous and urban land utilization in the city. However, development of low-slope hilly land easily induce potential risks of geologic hazards such as landslide and landslip. It may lead to further environmental losses in a watershed. Hence, it is necessary to study potential risks of geo-hazards in low-slope hilly land development in urban area. Based on GIS spatial analysis technique, we select a study area, Dali City in the Erhai Basin located in watershed belt of Jinsha River, Lancang River and Red River in Yunnan Province of China. Through studying some relevant key indexes and parameters for monitoring potential risks of geo-hazards, we establish a composite index model for zoning the area with potential risks of geo-hazards in development of low-slope hilly land in the study area. Our research findings indicate that the potential risks of geo-hazards in eastern Dali City is relatively low while of that on slow hills with gentle slopes in the western area are relatively high. By using a zoning research method, generated maps show geological information of potential risks of geo-hazards on low-slope hilly land which provide important messages for guarding against natural geo-hazards and potential environmental losses in a watershed.

鄱阳湖自然保护区湿地植被生物量空间分布规律

PDF HTML阅读 XML下载 导出引用 引用提醒 鄱阳湖自然保护区湿地植被生物量空间分布规律 DOI: 10.5846/stxb201307301983 作者: 作者单位: 中国科学院南京地理与湖泊研究所;湖泊与环境国家重点实验室,中国科学院南京地理与湖泊研究所;湖泊与环境国家重点实验室,中国科学院南京地理与湖泊研究所;湖泊与环境国家重点实验室,中国科学院南京地理与湖泊研究所;湖泊与环境国家重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 中国科学院南京地理与湖泊研究所"一三五"战略发展规划项目(NIGLAS2012135001);国家自然科学基金项目(41401506) Spatial distribution of wetland vegetation biomass in the Poyang Lake National Nature Reserve, China Author: Affiliation: Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences,Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences,Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences,Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:探明区域湿地植被生物量的空间分布规律及其变化趋势,对于更好地保护候鸟生境、制定合理的湿地保护政策具有重要的意义。以鄱阳湖国家级自然保护区为研究对象,基于2000-2011年研究区MODIS植被指数产品和同期的植被生物量调查资料,建立了湿地植被生物量的遥感估算模型。在此基础上利用GIS空间分析方法,系统分析了保护区近10年来湿地植被生物量的空间分布规律及其季节变化特征。研究结果表明:(1)MODIS增强型植被指数的乘幂模型可以较好地模拟研究区湿地植被生物量的鲜重,拟合模型总体精度达到91.7%。(2)多年平均生物量呈现"岛屿型"空间分布模式:各子湖泊及洼地中心处,表现为水生植被群落为主的低生物量区(<285 g/m2);湖心水体外围14-15m的高程区域,分布着以苔草群落为主的中生物量区(285-830 g/m2);高程位于16-18m的河口三角洲及天然堤坝区域,表现为以蒿、荻和芦苇群落为主的高生物量区。(3)保护区植被群落分布具有特定的季相变化特征,高、中、低生物量区在不同的月份呈现出不同的空间生消和演进规律,鄱阳湖水位的周期性涨落是影响其变化的一个重要扰动因子。 Abstract:Vegetation is one of the important components of wetland, and vegetation biomass is a key indicator of the health status of the wetland ecosystem. Comphrehensive understanding of spatial distribution of vegetation biomass and its temporal variation is a pre-requirement for effective protection of bird habitats and scientific planning of wetland conservation. In this regard, it has been one of central topics in hydro-ecology, wetland ecology and vegetation ecology in past decades. In recent years, vegetation change has become one of major concerns with frequently occurred extreme droughts in the Poyang Lake National Nature Reserve (PLNRR) of China. To investigate the spaital changes of vegetation, MODIS (Moderate resolution Imaging Spectrordiometer) vegetation index products (MOD13Q1) were used to construct a model for retrieval of vegetation biomass with the coincident field data in PLNRR for the period from 2000-2011. GIS spatial analysis techniques were used to analyze the spatial patterns and seasonal variations of wetland vegetation biomass. Our findings can be summerizes as follows: (1) the power function best describe the relationship between MODIS-EVI (Enhanced Vegetation Index) and green yield of vegetaiton in PLNRR, with an overall accuracy of 91.7%. (2) Multi-year average of vegetation biomass displayed an island-like spatial pattern and can be classified into three zones. Vegetation biomass was lower than 285g/m2, dominant with aquatic vegetation communities, for the bottom areas near the center of lakes. It ranged from 285 to 830 g/m2, dominant with sedge communities, for the periphery of the lakes with an elevation of 14-15 m. The biomass was higher than 830 g/m2 dominant with wormwood and reed communities, for surrounding delta or dyke areas with an elevation of 16-18 m. (3) Vegetation biomass showed different seasonal variations in each zone, which was jointly affected by multiple factors. Lake stage is the most important factor in regulating the spatial development of the vegetation biomass. Overall, the results should be not only helpful for understanding the change in biodiversity and ecosystem stability, but also provide a scientific basis for effective management and protection of wetland resources in the PLNRR. 参考文献 相似文献 引证文献

The pattern of available construction land along the Xijiang River in Guangxi, China

The assessment of construction land potential is a key foundation in the processes of future urbanization, development, and industrialization. Given the rapid economic growth, large population and scarce per-capita land in China, the assessment of construction land potential would be significant to diagnosing land resources and making sound development strategies. This paper assesses the amount, grade and spatial pattern of available construction land based on a multifactor distributed algorithm, an extraction process of potential land suitable for construction, and GIS spatial analysis techniques using 1:50,000 DEM and 1:100,000 land use data. A 20km band and seven urban regions along the Xijiang River in the Guangxi Zhuang Autonomous Region of China were selected for this case study. The results show that available construction land in the study area amounts to 1962.64km2, or 4.82% of the total land area (0.66% more than current construction land). Although there are obvious spatial disparities in the location of available construction land and current development demands, these discrepancies can be resolved by combining the Requisition–Compensation Balance policy for cultivated lands in different regions with layout planning adjustments. Overall, there is a high concentration of land suitable for construction located on the eastern side of the Liujiang River, bordering Laibin and Liuzhou cities. This zone is also well-suited for the longer-term development of a Liuzhou–Laibin New Town. In contrast, the limited potential for suitable construction land in the surrounding areas of Baise, Chongzuo, Laibin, Guigang and Wuzhou indicate the need for directional and site-specific development during future exploitation and construction.

The Campus of University Earthquake Disaster Prevention Planning - The Research of Spatial Pattern Based on GIS

Abstract In the background of rapid urbanization and frequent earthquakes, earthquake prevention planning has become an important topic of current research. Universities are irreplaceable shelter, as they are public institutions with a lot of open space. This article puts forward the concept of disaster prevention With the refuge behavioral and psychological characteristics of people in the campus when the earthquake happens, it integrated uses GIS spatial analysis technique, takes Shandong Agricultural University as an example, and studies the spatial pattern of earthquake prevention planning in campus from five aspects. The aspects include building distribution, population distribution, analysis of service radius, infrastructure configuration and choice of the optimal refuge path. On the basis of researches above, reform proposals and specific strategies are put forward to build the safe and harmonious prevention campus. Key words

Dynamic Changing Analysis of Regional Environmental Risk Based on Spatial Population Distribution of Different Time Scales

The study simulates the changes of the population spatial distribution at three periods (daytime of workdays, daytime of non-workdays, and night) in 2012 in Dagushan peninsula of Dalian Development Zone on the ground of change in land use, based on the multi-temporal visual interpretation of remote sensing and GIS spatial analysis techniques. It establishes the individual risk contours and societal risk F-N curves in different periods of Dalian Qihua area according to risk prediction model, and then reveals the dynamic changing mechanism of regional environmental risk.

Using ESDA with social weights to analyze spatial and social patterns of preschool children's behavior

To study the development of spatial and social behavior of preschool children, micro-level spatiotemporal data were collected for the first time in both spatial and social context using a novel behavioral coding system. These unique behavioral data enable us to explore the group-level, dynamic, spatial, and social patterns of preschool children's playing behavior from a hybrid geographic and social perspective. In this research, GIS and exploratory spatial data analysis (ESDA) techniques are employed together to study group-level spatial and social behavior emerging from children's everyday activities and interactions. ESDA with social weights is proposed to explore spatial and social patterns of preschool children's behavior at the same time. The results highlight the utility of this approach for studying the relationships between preschool children's playing behavior and preschool's environmental settings and the relationships between preschool children's personal activities and the formation of their social network space.

Landslide Susceptibility Mapping for the Urmia Lake basin, Iran: A multi- Criteria Evaluation Approach using GIS

Although typically small in terms of their spatial footprint, landslide hazards are relatively frequent in Northern Iran. We assess landslide susceptibility for the nearly 20.000 km2 large study area of the Urmia lake basin which is dominated by agricultural land use but includes the major settlements areas of the East Azerbaijan province, Iran. Landslide factors are established in form of GIS dataset layers including topography, geology, climatology and land use. After pre-processing all data layers are standardized based on a fuzzy logic model. An Analytical Hierarchical Process (AHP) delivers the weights for the GIS-analysis. Datasets are combined by GIS spatial analysis techniques and a landslide susceptibility map of the study area is created. An existing inventory of known landslides within the case study area was compared with the resulting susceptibility map. We found that high susceptible zones cover about 4.47% (944 km2) of the total area whereby geological outcrops of sedimentary and volcanic formations such as volcanic ash contribute most to the landslide susceptibility. Due to the dynamic growth of settlements especially in the vicinity of the city of Tabriz landslide hazards may cause even more damage in the future.The resulting information of this research is useful for a) a better understanding of existing landslides and their origins in North-Western Iran, b) supporting emergency decisions and c) prioritization of efforts for the reduction and mitigation of future landslide hazards.

The Urban Ecological Sensitivity Analysis of Enshi city Based on GIS and Analytic Hierarchy Process Model

With the rapid development of urbanization in China, the ecological environment is more and more seriously threatened; most cities should be focused on urban ecological environment construction and protection. In this paper, we choose the vegetation, slope, elevation, surface river system as the factors, and their weights were determined by analytic hierarchy process (AHP). Applying with GIS spatial analysis technique, the ecological sensitivity of the four factors was divided into four grades which contains high sensitive area, moderately sensitive area, low sensitive area and insensitive area areas occupied 9.43%, 36.46%, 50.61% and 3.50%. There existed a significant spatial differentiation in the ecological sensitivity of Enshi city. This study could provide scientific references for the city's environmental protection and economic development, to help its economic growth.

The Dynamic Analysis of Biocapacity and Driving Force in Minqin Oasis of Western China over the Past 20 Years

Ecological environment is the basis for human interdependence and development, so regional economic development must take into account the security situation of ecological environment and biocapacity. Based on the Ecological Footprint methodology, using remote sensing and GIS spatial analysis techniques, the biocapacity of Minqin oasis in Gansu in 1990, 2000 and 2009 was quantitatively calculated, and its spatio-temporal pattern analysis was also analyzed. The results showed：over the past two decades, there have been increasingly noticeable alterations to Minqin oasis; as a result, land reclamation activities have led to an increase in the areas of cropland, meaning that its biocapacity is rising, while the biocapacity of forest and pasture is decreasing. The biocapacity in space shows that the high-value area aggregation is augmented, there is an increased scope of area, and the focus of biocapacity has shifted. However, after 2000, with the water shortage, abandonment issues being highlighted and the aggravation of desertification, biocapacity has decreased, and additionally, the relationship between land and man has become strained. The changes of biocapacity are all closely linked with population growth, socio-economic development, agriculture structure, and water scarcity.

An Analysis of Sustainable Development Based on a Comparison of the Pre- and Post-Disaster Biocapacity and Ecological Footprint in Zhouqu County,China

Zhouqu County is not only an impoverished area but also a poor environment region. Frequent occurrence of geological disasters in Zhouqu, which largely determines the quality of ecological environment, affects the regional sustainable development. In this paper, on a case study of Chengguan Town of Zhouqu, two TM images acquired in pre- (2008)and post-disaster(2010) were selected to conduct the research, using remote sensing and GIS spatial analysis techniques. The state of the ecological environment and sustainable development of the region were evaluated by using the ecological footprint methodology. The results show: Firstly, the biocapacity of built-up area and cropland are reduced by 318.50gha and 82.78gha after debris flow disaster respectively, followed by forest land, grazing ground, fishing ground and barren ground, which has played a serious impediment in economic development; Secondly, the ecological deficit reaches to -0.9245gha/per-cap before disaster, however, it reduces to -1.0691gha/per-cap after disaster. This indicates that Chengguan Town is not sustainable development, after sudden disaster, the situation of unsustainable development becomes more serious; Thirdly, it is found that debris flow and landslides are mainly not only in forest land and cropland, also areas containing many people and buildings, which shows geological disasters has played a significant impact on the socio-economic development. Finally, this article provides scientific references for the restoring of ecological environment as well as scientific disaster relief after the debris flow disaster. Therefore, strengthening management and mitigation techniques of disaster is benefit to humans and socio-economic sustainable development.

Assessing construction land potential and its spatial pattern in China

The assessment of construction land potential is a key foundation in the processes of future urbanization, development, and industrialization. Given its background of land resources scarcity, there is a critical need to precisely evaluate land resources in China, especially its construction land potential. This paper determines the thresholds of factors based on references in different fields, defines the arithmetic formulae according to the logical relations of the factors, extracts data from the maps, and calculates the results. This assessment uses GIS spatial analysis techniques, Digital Elevation Models (DEMs), TM remote sensing land use map, administrative maps at the county level, and land use investigation data to derive the spatial pattern of construction land potential of China for 2008. The results show that: (1) construction land potential in China amounts to 283,400 km 2, which accounts for 2.99% of total land area and 0.021 ha/person; and (2) the spatial distribution of supply and demand of construction land potential currently is unbalanced, with areas such as Central China, East China, and metropolitan regions having low potential but high demand, while areas such as the northern part of China having high potential but low demand. It is suggested here that construction land potential could be seen as a key integrative indicator of the land carrying capacity of various regions for future population aggregation, industrialization and urbanization development. The assessment of construction land potential would be significant to diagnosing land resources and making sound development strategies in order to achieve regional sustainable development.