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1.
Rapid change in land use and land cover (LULC) and unplanned urban expansion in Dhaka City, Bangladesh, receives continuous attention from local policymakers and the international community. This study employed a supervised classification procedure and postclassification change detection technique to estimate major changes between different LULC classes. The study revealed that built-up area increased significantly from 1989 to 2014. The total urban growth of 81.54 percent resulted in a substantial decrease in natural vegetation cover and agricultural land. In addition, water bodies have declined consistently over the last twenty-five years. The overall accuracy of LULC change maps produced from Landsat data ranged from 89.72 percent to 92.97 percent. The results should contribute to ongoing LULC information updates while forecasting possible future LULC change and sustainable development under greater population density. 相似文献
2.
Rohan Wickramasuriya Laurie A. Chisholm Marji Puotinen Nicholas Gill Peter Klepeis 《International journal of geographical information science》2013,27(8):1497-1513
Spatial simulation models have become a popular tool in studying land use/land cover (LULC) change. An important, yet largely overlooked process in such models is the land subdivision, which is known to govern LULC change and landscape restructuring to a large extent. To fill this gap, we propose an efficient and straightforward method to simulate dynamic land subdivision in LULC change models. Key features in the proposed method are implementing a hierarchical landscape where adjacent cells of the same LULC type form patches, patches form properties, and properties form the landscape and incorporating real subdivision layouts. Furthermore, we use a queue-based modified flood-fill algorithm to dynamically reset LULC patches following a subdivision. The proposed subdivision method is demonstrated in action using a prototype agent-based LULC model developed for an amenity landscape in Australia. Results show that it is computationally feasible to run the subdivision method even as spatial resolution is increased, thus providing a proven means for spatial simulation models to dynamically split parcel land. 相似文献
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中尺度流域土地利用/土地覆盖变化评估--以伊洛河中部地区为例 总被引：18，自引：7，他引：18
将规范分析与实证分析相结合，提出了一个评估区域各点位土地利用／土地覆盖变化的新方法：（1）采用相对原则观察一时段内的变化方向；（2）物理模型与统计模型相结合，基于区域实际情况建立生境适宜性参照基准；（3）用多变量分析方法量度各点位与参照基准的差异。结合GIS和遥感技术，这种方法被应用于伊洛河中部地区的研究中。 相似文献
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Land use and land cover (LULC) change in the Ganges-Brahmaputra delta (GBD) poses significant challenges towards future environmental sustainability of the region and requires regional scale monitoring of key bio-physical variables and changes in their inter-relationship over space and time. Focusing on the southern part of the lower GBD region along the international border of India and Bangladesh, this study examined the spatio-temporal variability of LULC change and its relationship with Land Surface Temperature (LST). Furthermore, LULC-LST relationships were compared between Indian and Bangladesh part and its trend in and around big cities (with more than 1 million population) and towns (with more than 100,000 population) was investigated. Results showed that LST changes were predominantly driven by LULC changes on both sides of the border. Urban growth is the dominant form of LULC change, and the rate of land change was faster in 2005–2010 time period than 1989–2005. Over the period of 21 years, mean January LST decreased by approximately 1.83 °C in Indian part and 1.85 °C in the Bangladesh part. Areas that changed from to rural from agricultural experienced decrease in mean LST, whereas those areas that changed to urban from either agriculture or rural, experienced increase in mean LST. The relationship between LULC and LST are same on both sides of the Indo-Bangladesh border. In bigger cities like Kolkata (in India) and Khulna (in Bangladesh), there is a high spatial variability in relationship between LULC and LST compared to large towns. The LULC-LST relationship in large towns in India was influenced by proximity to Kolkata and coastal areas, whereas in Bangladesh no such influence was evident. The results and the data produced in this study are crucial for monitoring LULC changes, for developing spatial decision support system, and thus will be helpful to address the current challenges of land management in the GBD region. Changes in the LULC and LST are important indicators of GBD's environmental health and access its vulnerability and thus the present findings serve as baseline information for future studies seeking to examine the impact of differential policies on the LULC change in the region. 相似文献
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Temperate forest represents the smallest area among the main world's forest biomes, but is one of those most threatened by forest loss. Chile contains most of the temperate forest in South America and more than half of the temperate forest in the southern hemisphere. Chilean temperate forest is considered to be one of the world's biodiversity hotspots. In this study we assessed the rate of land use and land cover (LULC) change over time, identified the main LULCs replacing native forest, and described how changes have evolved in contrasting physiographical conditions and through different historical phases of the landscape over the last 40 years. To achieve this, we analysed LULC change with particular focus on forest cover in three areas representing different physiographical conditions and histories of human occupation in the Araucanía Region of Chile, namely the Central Valley, the Coastal range, and the Andean range. We found substantial differences in temporal and intra-regional patterns of forest loss and LULC change. In the Central Valley, forest loss started long ago, and the area occupied by native forest nowadays is less than 5% of the landscape. In the Coastal range, rapid land cover change has taken place since 1973, with an increasing rate of forest loss over time. We detected a similar but less intense pattern in the forests of the Andean range. Overall, the general pattern points to a process of landscape homogenization in all three physiographical areas. Exotic tree plantations have spread over large geographical areas, becoming the dominant land cover. Land cover change in the Araucanía Region reflects a model of change in which areas with better environmental conditions and accessibility are occupied first for productive activities. As the availability of suitable areas for the expansion of productive activities diminishes, these activities start to move into physiographical areas which were previously “protected” by adverse environmental conditions or poor accessibility. This model of production growth could lead to the complete deforestation of areas outside national protected areas, and other areas which still remain inaccessible due to technological restrictions on exploitation. 相似文献
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The objective of this paper is to document the role of fire in shaping the landscape by identifying links between historical fire records and the current landscape indicating that fire favors certain land use/land cover (LULC) types. We geo-referenced fire records taken from 1922 to 2000 in Aitoloakarnania, the largest prefecture -in terms of surface area- of Greece and compared the past LULC classes where fires burned to the present landscape. The outputs indicated a shift of the historic fire ignition points from natural to agricultural-related LULC classes since a significant proportion of fire incidents that, according to the fire records, burnt natural vegetation units is currently located in agricultural landscape units. Additionally, a significant proportion of the fire-affected land cover classes retain their character thus supporting the argument that these classes, especially fire-prone or fire-resistant, have developed mechanisms to cope with fire. In such ecosystems the role of fire is to maintain rather than transform land cover classes.The findings of this research lead us to conclude that fire can be perceived as a long-term landscape modifier in the Mediterranean, although its effects may vary from region to region because of differences in regeneration patterns among the main land cover types, topographic constraints and local fire histories. Historical fire records extending back to the early 20th century proved to provide valuable information that can reveal interesting patterns of fire burning history and explain present land cover and use patterns. This knowledge, documented from historical records, can be used to develop fire management and land cover/land use management planning. 相似文献
8.
土库曼斯坦典型绿洲土地利用/覆被变化和景观格局的时空演变 总被引：2，自引：0，他引：2
当前开展遥感和GIS技术支持下的土库曼斯坦生态环境领域方面的研究,不仅可以保障中国的能源战略安全,同时也可为中国西北干旱区的生态环境演变及可持续发展研究提供一定的借鉴。本文以土库曼斯坦穆尔加布-捷詹绿洲为研究对象,基于1976年、1988年、2001年和2011年的Landsat MSS、TM/ETM+的4期遥感数据资料,应用GIS和景观生态学方法定量分析了研究区近40年的土地利用方式及景观格局的时空变化动态特征。结果表明：（1）研究区LUCC变化明显,主要表现为林地、耕地、沙地和盐碱地呈现增加趋势,草地、水域和其他用地呈现减少趋势。土地利用在1976-1988年变化最快的是草地,1988-2001年是水域,2001-2011年是草地,1976-2011年是耕地。（2）研究区内整体景观的空间变化表现为蔓延度指数、散布与并列指数和斑块结合度指数均呈现降低趋势,分离度、SHDI和SHEI均呈现增加趋势,表明斑块数目增多,景观破碎化程度加大,连通性降低。总之,要保障土库曼斯坦穆尔加布-捷詹绿洲土地资源与生态环境的可持续发展,必须注重土地利用格局最优化,确保景观格局与生态过程的连续性。 相似文献
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Based on four phases of TM images acquired in 1990, 1995, 2000 and 2005, this paper took Kitakyushu in Japan as a case study to analyze spatial change of land use landscape and corresponding effects on environmental issues guided by landscape ecology theory in virtue of combining technology of Remote Sensing with GIS. Firstly, land use types were divided into 6 classes (farmland, mountain, forestland, water body, urban land and unused land) according to national classification standard of land use, comprehensible ability of TM image and purpose of this study. Secondly, following the theory of landscape ecology analysis, 11 typical landscape indices were abstracted to evaluate the environmental effects and spatial feature changes of land use. Research results indicated that land use has grown more and more diversified and unbalanced, human activities have disturbed the landscape more seriously. Finally, transfer matrix of Markov was applied to forecast change process of land use in the future different periods, and then potential land use changes were also simulated from 2010 to 2050. Results showed that conversion tendency for all types of land use in Kitakyushu into urban construction land were enhanced. The study was anticipated to help local authorities better understand and address a complex land use system, and develop improved land use management strategies that could better balance urban expansion and ecological conservation. 相似文献
10.
近年来,全球及区域生态系统服务均呈现出快速变化趋势,分析研究生态系统服务变化的驱动机制有助于精准模拟未来生态系统服务情景,进而服务于生态系统管理决策的科学制定。虽然已有部分研究探讨了土地利用或气候变化对生态系统服务的影响,但生态系统服务变化的驱动机理与应对策略亟待全面揭示。为此,该文回顾总结了国内外关于生态系统服务变化驱动机制的研究成果,并分析归纳了生态系统服务变化的主要驱动因子与未来模拟技术,结果发现:(1)土地利用与气候变化是造成生态系统服务变化的主要因素,且相互作用共同驱动生态系统服务的变化;(2)生态系统服务变化的单影响因子识别取得较大进展,但多种影响因子的交互作用及其在生态服务变化中贡献亟需清晰分解;(3)基于遥感与气候模型的多情景模拟是预测未来生态系统服务变化的主要手段,但需要科学模拟多因素交互作用下的综合影响及其应对途径;(4)未来研究应加强人类活动对生态系统服务影响的分解与模拟,研发区域生态系统服务对重大生态工程的时空响应与探测技术,以科学指导区域生态保护建设与规划布局。 相似文献
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LUCC驱动力模型研究综述 总被引：30，自引：2，他引：30
驱动力研究是土地利用变化研究中的核心问题。土地利用变化驱动力模型是分析土地利用变化原因和结果的有力工具，模型通过情景分析可为土地利用规划与决策提供依据。基于不同理论的驱动力研究方法很多，论文选取了几种国内外应用较多的LUCC驱动力模型进行综述，分析了每个模型的优缺点及适用范围，最后得出结论：1) 基于过程的动态模型更适于研究复杂的土地利用系统。2) 基于经验的统计模型能弥补基于过程的动态模型的不足。3) 基于不同学科背景的模型进一步集成将是LUCC驱动力模型未来的发展趋势。 相似文献
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Landscape position and spatial patterns in the distribution of land use within the southern Appalachian Mountains 总被引：1，自引：1，他引：0
Understanding the forces that influence the distribution of land use and land-use change (LUC) is an essential step in developing effective strategies for managing these issues. We examined the influence of landscape position on spatial patterns in land-use distribution within the Little Tennessee River Basin (LTRB) of the southern Appalachian Mountains. We show that landscape position, defined with respect to both natural and anthropogenic spatial variables, provides for the identification of statistically significant differences in the distribution of common forms of land use in the study region. Using the same variables, significant differences in the landscape positions subject to land-use change in the LTRB are also examined. These results suggest landscape position exerts a strong influence on the distribution of different forms of land use and the likeliness of given area undergoing LUC. The approach presented here, of considering land use as a function of landscape position that responds to both natural and anthropogenic forces, may prove useful in aiding the development of future strategies to address the consequences of land use in many regions. 相似文献
13.
Predicting plausible impacts of sets of climate and land use change scenarios on water resources 总被引：3，自引：0，他引：3
Susanna T.Y. Tong Yu SunThushara Ranatunga Jie HeY. Jeffrey Yang 《Applied geography (Sevenoaks, England)》2012,32(2):477-489
Our world is changing at an unprecedented rate in terms of climate and land use, but these changes can affect our water resources. Hence, we need a methodology that can predict both their individual and agglomerative ramifications. Using the Little Miami River (LMR) watershed as a case study, this paper describes a spatial analytical approach integrating mathematical modeling and geographical information sciences to quantitatively examine the relative importance of the separate and combined hydrologic and water quality impacts of climate and land use changes.The Hydrologic Simulation Program - Fortran (HSPF) model was chosen in this study to simulate stream flow and nutrient transport process. Five hypothetical climate change scenarios were used to cover the possible ranges of variability in the year 2050. An enhanced population-coupled Markov-Cellular Automata (CA-Markov) land use model was developed to predict the 2050 land use pattern. When these scenarios were incorporated into the HSPF model, the future conditions in the LMR basin were postulated. The findings demonstrated that: 1) the LMR watershed would experience an increase in flow and nutrients under the 2050 land use projection, 2) stream flow and water quality impacts would be amplified when both climate and land use changes were simultaneously considered, 3) land use change (and in the case of the LMR watershed, urbanization) could help to alleviate water shortage during the dry years, 4) total phosphorus and nitrogen would increase under all future climate and land use scenarios; the highest increase was found under the combined wettest and future land use scenarios, and 5) the described approach is effective in simulating the hydrologic and water quality effects of climate and land use changes in a basin scale. These results are relevant to planners; they can be useful in formulating realistic watershed management policies and mitigation measures. 相似文献
14.
土地利用变化对生物多样性和生态过程有着深刻的影响,与城乡景观格局变化密切相关。尝试将土地利用变化驱动力——土地经济生态位的理论和方法引入到景观生态学当中,为城乡空间景观格局空间表征提供新的方法。通过选取表征景观格局指标的破碎化指数、分形维数,利用Envi4.8、Arcmap10.0,Fragstasts4.1等软件,以广东省惠州市为例,在分析土地经济生态位与景观类型、景观指数之间的关系基础上,对土地经济生态位变化下的城乡空间景观格局进行表征。结果表明：不同景观土地面积数量的增减与该类型土地经济生态位升降具有一致性的规律,土地经济生态位上升,相应的景观土地面积增大,反之则减小;土地经济生态位越小,表征景观格局的景观破碎化指数、分维数指数越大,破碎化指数与分维数指数的增减与土地经济生态位升降表现出一致性的规律,土地经济生态位上升,相应的破碎化指数、分维数指数则增大,反之则减小;城乡空间景观格局变化的发生主要出现在土地经济生态位高的区域。土地经济生态位的变化是城乡景观格局变化的重要影响因子,能够很好解释城乡空间景观格局特征。 相似文献
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湿地景观格局变化研究进展 总被引：45，自引：1，他引：44
湿地是自然界最富生物多样性的生态景观,具有重要的生态功能。湿地景观格局是各种生态过程综合作用的结果,具有高度的景观异质性,对景观的功能和过程有着显著的影响。湿地生态系统是世界上受威胁最为严重的生态系统之一,在自然因素和人类活动的影响下发生了大面积的转化或丧失。本文从湿地景观格局研究方法、面积变化、景观类型转化、驱动力以及动态模型、湿地景观格局指数以及湿地景观格局与气候变化之间的关系等方面综述了湿地景观格局变化的研究进展,指出湿地景观格局变化及其生态效应和高原湿地景观格局变化与气候变化之间的关系是未来研究的重点领域。 相似文献
17.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):175-184
The coastal heath region along the western coast of Norway, dominated by Calluna vulgaris, is undergoing rapid change. Vegetation changes are caused by changes in management, including reduced frequency or abandonment of periodic heath burning and reduced cutting and grazing. The islands of Froan, in the outermost part of Sør-Trøndelag County in mid-western Norway, are dominated by coastal heath in a state of recession due to reduced traditional land use. The coastal heath is acknowledged as vulnerable and valuable by national environmental authorities, and local landscape management is supported by different national subsidies. The authors mapped the vegetation on Froan and used rule-based GIS-modelling to predict the relative potential for future vegetation changes. The model was based on a range of map layers, including management themes such as history of heath burning and peat removal, current practices of sheep grazing, and also themes derived from the vegetation map, such as soil nutrients, soil moisture and present management status. The resulting model output provides relative probabilities of future changes under different land-use scenarios, and highlights where management efforts should be focused in order to maintain the traditional landscape character. 相似文献
18.
A landscape mosaics approach for characterizing swidden systems from a REDD+ perspective 总被引：1，自引：0，他引：1
Cornelia Hett Jean-Christophe Castella Andreas Heinimann 《Applied geography (Sevenoaks, England)》2012,32(2):608-618
Swidden agriculture is often deemed responsible for deforestation and forest degradation in tropical regions, yet swidden landscapes are commonly not visible on land cover/use maps, making it difficult to prove this assertion. For a future REDD+ scheme, the correct identification of deforestation and forest degradation and linking these processes to land use is crucial. However, it is a key challenge to distinguish degradation and deforestation from temporal vegetation dynamics inherent to swiddening. In this article we present an approach for spatial delineation of swidden systems based on landscape mosaics. Furthermore we introduce a classification for change processes based on the change matrix of these landscape mosaics. Our approach is illustrated by a case study in Viengkham district in northern Laos. Over a 30-year time period the swidden landscapes have increased in extent and they have degraded, shifting from long crop-fallow cycles to short cycles. From 2007 to 2009 degradation within the swidden system accounted for half of all the landscape mosaics change processes. Pioneering shifting cultivation did not prevail. The landscape mosaics approach could be used in a swidden compatible monitoring, reporting and verification (MRV) system of a future REDD+ framework. 相似文献
19.
Accurate information on land use and land cover (LULC) is critical for policy decisions especially for management of land and water resources’ activities in large river basins around the world. Phenology based LULC classification is the most promising approach particularly in the areas with diversified cropping patterns. Sometimes in large river basins, local climate and topography provides two different phenological information sets for the same crops in the same season. Based on accurate phenological information of the main crops in spatially segregated units, the remote sensing based classification was used to map the LULC changes for a period of 2003–2013 in the Kabul River Basin (KRB) of Afghanistan. We used remotely sensed Normalized Difference Vegetation Index (NDVI) products of Moderate-resolution Imaging Spectroradiometer (MODIS) from Terra (MOD13Q1) and Aqua (MYD13Q1) with 250 m spatial resolution for this study. The overall accuracy (mean) of the LULC classification throughout the study period was around 68.15% ± 9.45while the producer and user accuracies (mean) were 75.9 ± 11.3% and 76.4 ± 11.2%, respectively. Results show that the cropping patterns vary significantly in the spatially disaggregated units. From 2003 till 2013, the ground coverage of wheat, barley and rice was increased by 31%, 7% and 32%, respectively. Overall, there has been only 2% increment in the agricultural area across the KRB between 2003 and 2013. This relatively increased trend of land cover change has taken place as a result of partial improvement in political stability as well as investment in irrigation infrastructure and agricultural development in the region. This study further provides insight to develop new agriculture strategies in order to maintain the ecosystem required to fulfil the rising food demands. 相似文献
20.
Land change was assessed in the Albertine rift region (ARR) using its central section of north-western Rwanda as case study. This region is one of Africa's most ecologically sensitive environments under severe pressure from human activities. The study maps and quantifies the spatial extent of land use-land cover (LULC) changes between 1987 and 2016 from Landsat images. Transitions between five major land classes were identified in order to understand the trajectory of observed changes. In terms of gains, the forest class, the urban built-up and bare land class increased by 9% and 4% respectively over the study period. The gains of forest were mainly derived from the afforestation of some agricultural lands in the southern part, whereas the gains of built-up and bare lands were mostly from cultivated land which was a net losing class. Forest increase is in line with government's policy to increase the national forest cover to 30% by 2020. Forest losses occurred mostly outside protected areas due to land conversion for settlement and agricultural purposes. Much needed information about changes in LULC over the last three decades is provided. This study demonstrates in a timely manner how to analyse and monitor LULC change and the drivers in an environment where field based research is a challenge due to the mountainous terrain. The ecological richness of the region, which coincides with heightened human population pressure, necessitates the monitoring of land change as input for improving land use planning with focus on conserving biodiversity. 相似文献