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1.
Adeniyi  P. O. 《GeoJournal》1981,5(3):209-223
Basic to the study of urban growth is information on population and land use changes. These basic data are generally lacking in Nigeria. This paper examines and assesses the growth of urban land use of Lagos (the Federal Capital of Nigeria) through a systematic utilization of sequential serial photographs (taken in 1962 at a scale of 1:40,000, and in 1974, at a scale of 1:20,000) and computer techniques. The land use data resulting are then used in evaluating the population growth of Lagos. The resulting population estimate is then compared with the available population data. The study concludes by recommending the use of remote sensing, especially aerial photography for the acquisition of basic urban data not only in Nigeria but also in other developing countries lacking in such data.  相似文献   

2.
Rapid urban expansion due to large scale land use/cover change, particularly in developing countries becomes a matter of concern since urbanization drives environmental change at multiple scales. Dhaka, the capital of Bangladesh, has been experienced break-neck urban growth in the last few decades that resulted many adverse impacts on the environment. This paper was an attempt to document spatio-temporal pattern of land use/cover changes, and to quantify the landscape structures in Dhaka Metropolitan of Bangladesh. Using multi-temporal remotely sensed data with GIS, dynamics of land use/cover changes was evaluated and a transition matrix was computed to understand the rate and pattern of land use/cover change. Derived land use statistics subsequently integrated with landscape metrics to determine the impact of land use change on landscape fragmentation. Significant changes in land use/cover were noticed in Dhaka over the study period, 1975–2005. Rapid urbanization was manifested by a large reduction of agricultural land since urban built-up area increased from 5,500?ha in 1975 to 20,549?ha in 2005. At the same time, cultivated land decreased from 12,040 to 6,236?ha in the same period. Likewise, wetland and vegetation cover reduced to about 6,027 and 2,812?ha, respectively. Consequently, sharp changes in landscape pattern and composition were observed. The landscape became highly fragmented as a result of rapid increase in the built-up areas. The analysis revealed that mean patch size decreased while the number of patches increased. Landscape diversity declined, urban dominance amplified, and the overall landscape mosaics became more continuous, homogenous and clumped. In order to devise sustainable land use planning and to determine future landscape changes for sound resource management strategies, the present study is expected to have significant implications in rapidly urbanizing cities of the world in delivering baseline information about long term land use change and its impact on landscape structure.  相似文献   

3.
Xiaofang Li 《GeoJournal》1990,20(4):353-357
China has long been an agricultural country. Cultivated land is mainly used for growing staple foods. Before liberation (1949), land was scarcely planted for cash corps. Factors exerting influence on land use are: The traditional Chinese way of intensive land use, and population pressure as well as economic situation. The structure of recent developments of land use exhibits: altidutinal agricultural land use, intercropping of crops and trees, twotier and multi-tier land use.  相似文献   

4.
In the period between 1965 and 1976, when German geographers carried out their fieldwork for the Afrika-Kartenwerk under the sponsorship of the German Research Society, remarkable progress in urban development especially in Lagos could be observed. The cooperation with the Federal Survey Department of Nigeria gave the opportunity for collecting several series of aerial photographs which bring into focus some stages of the overwhelming urban expansion.The materials presented here have been selected to demonstrate some regional structures of the Nigerian capital. — In the geography of today the scientific evaluation of aerial photographs together with findings from local observation and historical as well as statistical data is still undervalued. Through this technique, the more classical and conservative method of geographical analysis, relying on subjective judgement, may regain some of its importance, which it once had in the age of exploration of new territories.Where data is scarce and written records of urban expansion are not available or difficult to extract, aerial photographs can give an impression of certain stages of urban growth. A functional analysis under geographical aspects has to be regarded by changes within spatial units in order to the factors of influence. Those factors are numerous, their influence will cause changes in a series of pushes arising from economic developments of the vast hinterland as well as from social conditions of certain groups of the population. In a metropolitan center, as Lagos, the highest ranking central place of Africa's most populous nation, heterogenous events and a confusing number of planning decisions must be taken into consideration. One consequence of nationwide regional interactions with the metropolis is migratory population dynamics. In pursuing lines of interaction, which originate from economic power, population density, and natural resources, one can hardly isolate a single element of influence because all factors are closely interrelated. For Lagos, there is only limited data available on the social and economic standard of the population, valid basic demographic figures of some value are not available.One still has to accept very rough estimates on population figures, number of industrial workers, the standards of housing and the social and economic hierarchy of the population. The present retrospective analysis of aerial photographs gives an interpretation of the regional structure of the town and indicate possible future development.  相似文献   

5.
深圳市国土规划地质环境管理体系的构想   总被引:1,自引:0,他引:1  
本文从深圳市地区地质环境现状出发,初步查明了开发区活动断裂及隐伏岩溶地面塌陷等多种地质灾害对城市规划建设的影响和危害。市哒,府有关主管部门借鉴了美国、香港的某些管理经验,结合城市地区的环境地质问题及时采取了治理措施,科学、合理地开展国土规划和城市建设,总结出一套城市国土规划和地质环境管理体系。可供同类型城市管理工作借鉴和参考。  相似文献   

6.
开发区土地集约利用评价中指标理想值的确定   总被引:1,自引:0,他引:1  
针对开发区土地集约利用评价中指标理想值确定中存在的主观性强、整体性差等问题,提出了基于目标值法、统一理想值法与区域修正法相结合的理想值确定方法,并利用该方法对大连市6个国家级开发区进行了评价。结果表明,该方法能准确反映不同开发区在该区域的土地集约利用水平,更具科学性、客观性和引导性。  相似文献   

7.
Three years after the oil spillage and pipeline explosion that claimed about 100 human lives at Ijegun Community of Lagos–Nigeria, a combination of carefully designed 2D Electrical Resistivity Profilling and Vertical Electrical Sounding methods was deployed to map and characterise the subsurface around the contaminated site. Data acquired were processed, forward modelled and tomographically inverted to obtain the multi-dimensional resistivity distribution of subsurface. The results of the study revealed high resistivity structures that indocate the presence of contaminant (oil plumes) of different sizes and shapes around the oil leakage site. These high resistivity structures are absent in the tomograms and resistivity-depth slices computed for Iyana—a linear settlement not affected by oil spillage. The five geo-electric layers and the resistivities delineated in the area are the top soil layer, 220–670 Ωm; clayey sand layer, 300–1072 Ωm; top sand layer, 120–328 Ωm; mudstone/shale layer, 25–116 Ωm and the bottom sand layer, 15–69 Ωm. The base of the first four geo-electric layers corresponds to 3.9, 8.4, 27.2 and 34.6 m respectively. The two groundwater aquifers delineated correspond to the third and fifth geo-electric layers. The top aquifer has been infiltrated by oil plumes. The depth penetrated by the oil plume decreases from 32 m to about 24 m across the survey profiles from the two ends. It was concluded that the contaminant plumes from the oil spillage are yet to be completely degraded as at the time of the study. It is recommended that the contaminated site be remediated to remove or reduce the contaminant oil in the subsurface.  相似文献   

8.
GeoJournal - Planning of land use and infrastructure in advance for a population that is projected to grow rapidly is highly important for its sustainable development. A correlative approach of...  相似文献   

9.
采用主成分分析法并结合SPSS,对1999-2013年重庆市土地持续利用与生态环境的耦合关系进行分析,研究结果表明:1999-2013年土地持续利用指数逐年递增,土地开发利用强度逐年不断加大,城镇化大规模的建设是土地利用强度升高的主要原因;生态环境质量除了在2000-2004年生态环境指数呈“V”字型发展之外,总体呈上升态势发展;重庆市土地持续利用与生态环境耦合发展度由0.387 4(轻度失调衰退土地利用损益型)上升至0.754 0(中级协调发展经济主导型),但2011年情况有所变化,土地持续利用指数首次低于生态环境指数,耦合发展基本类型由生态主导型转向经济主导型发展,经济发展方式由土地利用制约型演变为生态环境制约型,生态环境效益滞后于土地资源经济效益。土地资源总体利用水平提高和生态环境改善的双重作用是耦合关系由失调发展转化为协调发展的主要原因。现阶段应坚持土地资源集约利用与保护并举,优化经济结构与技术创新齐下,发展循环经济和清洁能源,维系相对稳定的生态环境运行机制,确保重庆市土地资源可持续利用。   相似文献   

10.
Setyawan  Chandra  Lee  Chin-Yu  Prawitasari  Miky 《Natural Hazards》2019,98(2):697-718
Natural Hazards - Increasing land occupancy for farming without conservation principles, particularly in the Indonesian island of Java, is resulting in a severe erosion problem. This study...  相似文献   

11.
The integration of remote sensing, geographic information system, landscape ecology and statistical analysis methods was applied to study the urban thermal environment in Guangzhou. Normalized Difference Vegetation Index (NDVI), Normalized Difference Build-up Index (NDBI), Normalized Difference Barren Index (NDBaI) and Modified Normalized Difference Water Index (MNDWI) were used to analyze the relationships between land surface temperature (LST) and land use/land cover (LULC) qualitatively. The result revealed that, most urban built-up lands were located in the middle part, and high LST areas mostly and were in the middle and southern parts. Therefore, the urbanization and thermal environment in the middle and southern parts need to be determined. Land surface temperature increased with the density of urban built-up and barren land, but decreased with vegetation cover. The relationship between MNDWI and LST was found to be negative, which implied that pure water would decrease the surface temperature and the polluted water would increase the surface temperature. A multiple regression between LST and each indices as well as the elevation was created to elevate the urban thermal environment, which showed that NDVI, NDBI, NDBaI, MNDWI were effective indicators for quantifying LULC impacts on LST.  相似文献   

12.
The rapid development of cities in developing countries results in deteriorating of agricultural lands. The majority of these agricultural lands are converted to urban areas, which affects the ecosystems. In this research, an integrated model of Markov chain and cellular automata models was applied to simulate urban land use changes and to predict their spatial patterns in Tripoli metropolitan area, Libya. It is worth mentioning that there is not much research has been done about land use/cover change in Libyan cities. In this study, the performance of integrated CA–Markov model was assessed. Firstly, the Markov chain model was used to simulate and predict the land use change quantitatively; then, the CA model was applied to simulate the dynamic spatial patterns of changes explicitly. The urban land use change from 1984 to 2010 was modelled using the CA–Markov model for calibration to compute optimal transition rules and to predict future land use change. In validation process, the model was validated using Kappa index statistics which resulted in overall accuracy more than 85 %. Finally, based on transition rules and transition area matrix produced from calibration process, the future land use changes of 2020 and 2025 were predicted and mapped. The findings of this research showed reasonably good performance of employed model. The model results demonstrate that the study area is growing very rapidly especially in the recent decade. Furthermore, this rapid urban expansion results in remarkable continuous decrease of agriculture lands.  相似文献   

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Environment in arid conditions is dynamic and needs more investigation to understand the complexity of change. This spatiotemporal study will help to assess and monitor the land use and land cover change in the arid region of El-Arish area, where the climate and human activities are the major threats to rural development. In the past 11 years, dramatic changes of environment have been recorded in case studies. The post-classification comparison method was used to observe the changes using multi-temporal satellite images which were captured in the years 1999, 2001, 2005, and 2010. The overall accuracy of the produced thematic images was assessed regarding to the quantity and allocation disagreements. Five classes were defined in this investigation: bare soil, vegetation, urban, sand dunes, and fertile soil. From the year 1999 to 2010, fertile soil was increased by 13 %. Bare soil class occupied more than 50 % of land in the case study during for over a decade. From year 1999 to 2010, vegetation cover witnessed a dramatic increase. Soil and water management are the keys of land development and positive land use and land cover dynamics. Changing agricultural policies of using the available water resources are needed in the case study to prevent severe food shortage in the future.  相似文献   

16.
Yehua Wei 《GeoJournal》1993,30(4):435-440
Astract Recent economic reforms and shifts in land use planning in China have greatly changed the size and structure of urban land use. In this paper, an overview of the problems in urban land use and the impacts of economic reforms and planning policies on rapid urban land expansion and structural transformation is outlined. This is followed by statistical analyses to reveal determinants of urban land size. The study shows that urban land use in China has been improved, and urban land use size is related to urban reforms, urban land use adjustment, as well as to population growth and economic development.  相似文献   

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Edward R. Carr  Brent McCusker   《Geoforum》2009,40(4):568-579
In a previous paper [McCusker, B., Carr, E.R., 2006. The co-production of livelihoods and land use change: Case studies from South Africa and Ghana. Geoforum 37 (5), 790–804], we argued that land use and livelihoods could best be understood as co-produced, where land use and livelihoods are not separate objects of knowledge related to one another through abstract processes, but different manifestations of social processes through which individuals and groups come to understand the challenges facing their everyday lives, the various resources available to them to negotiate these challenges, and the strategies by which they can conduct that negotiation. In this paper, we examine the theoretical basis for “co-production” with the goal of using this approach to inform development interventions.  相似文献   

20.
坝上地区位于北京北部、内蒙高原南部,为典型的农牧交错带,生态环境十分脆弱,对环境反映非常敏感,是研究环境变化最理想的地区。该区距京、津逾200km,又是京、津地区的水源地和生态屏障,区位十分重要。该区人少地多,土壤中很少施用化肥、农药,养分分析数据更趋于客观。  相似文献   

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