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1.
Remote sensing technologies are increasingly used to monitor landscape change in many parts of the world. While the availability of extensive and timely imagery from various satellite sensors can aid in identifying the rates and patterns of deforestation, modelling techniques can evaluate the socioeconomic and biophysical forces driving deforestation processes. This paper briefly reviews some emerging spatial methodologies aimed at identifying driving forces of land use change and applies one such methodology to understand deforestation in Mexico. Satellite image classification, change analysis and econometric modelling are used to identify the rates, hotspots and drivers of deforestation in a case study of the southern Yucatán peninsular region, an enumerated global hotspot of biodiversity and tropical deforestation. In particular, the relative roles of biophysical and socioeconomic factors in driving regional deforestation rates are evaluated. Such methodological approaches can be applied to other regions of the forested tropics and contribute insights to conservation planning and policy.  相似文献   

2.
Central America's tropical forests have been felled more rapidly than those of any other world region during the latter half of the twentieth century. During this time, nearly half of Guatemala's forests were eliminated. Most of this deforestation has been concentrated in the northern department of Petén. The remaining forests in Petén are now mainly concentrated in the Maya Biosphere Reserve (MBR), the heart of the largest lowland tropical forest in Central America. The pace, magnitude, and geography of this trend is of critical importance to forest conservation and rural development efforts. This article examines socioeconomic, political, demographic, and ecological factors behind settler land use and forest clearing among 241 farm households in the Sierra de Lacandón National Park (SLNP), a core conservation zone of the MBR. Some of the factors positively related to forest clearing were household size, Q'eqchí Maya ethnicity, land owned in the previous residence, farm size, land title, and the cropping of velvet bean as a soil amendment. Education, off‐farm employment, and farm distance to a road were negatively related to farm‐level deforestation.  相似文献   

3.
ABSTRACT. Political dimensions of conservation abound. The biosphere-reserve model, however, depoliticizes the landscape by neglecting politics as a shaper of ecologies. To illustrate this process of depoliticization, I examine discourses about environmental degradation, power structures engaged in implementing conservation measures, and emerging landscapes in the Maya Biosphere Reserve. Conservationist discourses hold migrant farmers responsible for deforestation and land degradation in the Petén, to the neglect of wider socioeconomic conditions that perpetuate poverty in Guatemala. Sociospatial consequences include misdirected projects and landscapes that reflect the goals of nongovernmental organizations, not local people's needs and aspirations.  相似文献   

4.
The objective of this study was to better understand the linkages between spatial patterns of forest use, land use, and rates of deforestation. We focused on a region of the Brazilian Amazon characterized by a variety of spatial patterns of deforestation and that experienced rapid deforestation in the last decade: the colonization project “Pedro Peixoto” in the extreme East of Acre State. By combining time series of remote sensing data and household survey data, we tested the hypothesis that each spatial pattern of deforestation is associated with specific socio-economic characteristics of land managers. The statistical results support our hypothesis. However, spatial patterns of deforestation are not a consequence of the main economic activities. Rather, spatial patterns of forest use are linked to the pre-conceived design of the settlement project. The main economic activities are influenced by factors such as the property size, their location and disposition, and the availability of infrastructure.  相似文献   

5.
洮河流域土地利用/土地覆被变化及其驱动机制研究   总被引:1,自引:1,他引:0  
系统收集和整理1970s后期至2000s洮河流域土地利用/土地覆被、水文气象和经济社会发展数据,采用综合利用指数、转移矩阵、动态度、相关性和主成分分析方法及多元线性回归方法,得到结果表明,过去30 a,洮河流域总体表现为林、草面积减少、耕地面积增加、土地开发利用程度进一步提升。驱动因子相关性及主成分分析表明,洮河流域LULCC受“区域经济+农耕因素+城镇化和气候”3个主成分大类的交互影响和驱动;基于此构建的LULCC多元回归驱动模式,在率定期和验证期精度良好,能够反映洮河流域经济社会发展及区域气候对LULCC的驱动和影响。  相似文献   

6.
九寨沟自然保护区景观变化与保护   总被引:2,自引:0,他引:2  
立足于景观尺度,基于RS和GIS技术及景观生态学原理,使用巢式分析法研究了1975-2007年九寨沟自然保护区景观变化,包括景观格局、景观过程,讨论了景观变化的驱动因素.结果表明:1.最近30多年来,九寨沟自然保护区及外围圈层各类景观都发生了不同程度的变化:自保护区建立以来,林地、水域分别净增899.56 hm2、7.06 hm2,疏林/灌丛、草地分别减少440.52 hm2、970.60 hm2,耕地已全部实现退耕;而同期外围2个圈层的林地却分别减少9 012.23 hm2、25 975.28 hm2,水域减少16.89 hm2、0.83 hm2,建设用地增加376.58 hm2、1 340.35 hm2.草地增加4 883.18 hm2、56 462.11 hm2.在景观水平上,保护区破碎化程度最低,而多样性程度最高,但在类型水平上,保护区2007年的林地却仍然比1975年破碎.2.各种宏观政策,包括保护政策、旅游发展及其所引发的人类活动是九寨沟自然保护区及其外围2个圈层林地、建设用地、耕地景观变化的驱动因素,而自然地理过程是九寨沟自然保护区及其外围2个圈层冰雪/裸岩、水域景观变化的驱动因素.针对景观变化和未来面临的挑战提出了保护建议.  相似文献   

7.
The Cuyabeno Wildlife Production Reserve (Cuyabeno Reserve), located in the northeastern Ecuadorian Amazon, is a special protected area. Using a satellite image time-series, landscape ecology and evolving boundary definitions, shifts in landscape composition are described that focus on the spatial and temporal dynamics of land use and cover change (LUCC) within the vicinity of the Cuyabeno Reserve. Changes in local land tenancy and the implementation of protection buffers have accelerated the process of fragmentation and exacerbated the conflict between development and protection. Further, variations in management strategies and ownership histories confound LUCC patterns, rates, and trajectories.  相似文献   

8.
This study evaluates the dynamics and identifies the indirect biophysical and socio‐economic factors related to the recovery, degradation and deforestation of the tropical dry forest (TDF) cover in the municipality of Tehuantepec, Oaxaca, Mexico. Annual rates and transition matrices were determined to identify indirect factors; the cartographic information of 25 variables with shift points were overlaid and Generalized Linear Models (GLM) were applied. The change process with the greatest impact in TDF during the study period (1993–2011) was degradation, with 10468 ha degraded (12 per cent of the initial tropical cover); recovery of coverage was the second most important change process, with 4808 ha (5.5 per cent); and deforestation was the change process with the lowest impact, with a loss of 2800 ha (3.23 per cent). The net balance was negative, with a decrease (through land degradation and deforestation) of 8460 ha (9.75 per cent). The recovery of coverage was mainly associated with biophysical factors such as land suitability and accessibility to natural vegetation. On the other hand, deforestation and degradation of coverage were associated with both biophysical and socioeconomic factors such as land suitability, accessibility to natural vegetation, migration, marginalization, population pressure, economy, education and health. The findings of this study determined the spatial distribution of forest recovery, deforestation and degradation processes at a regional level, allowing for future researchers to focus their efforts at local and landscape levels. Also, the work allows for an approximation of the factors associated with the change processes studied, hence supporting the allocation of resources for the establishment of management, conservation, development and restoration strategies of tropical dry forests at the regional level.  相似文献   

9.
ABSTRACT. Tropical montane forests are known for their ecological importance. Most montane forests in Ecuador have been converted to agriculture, and those that remain are concentrated on the eastern cordillera. Understanding of land‐use‐land‐cover change in this ecological zone is inadequate. Using remote sensing (Landsat tm, spot ) and fieldwork, we document land‐use‐land‐cover change in two watersheds on Ecuador's eastern cordillera (Cañar Province). During the 1990s the region experienced a 0.58 percent annual rate of deforestation, but two areas within it show active signs of re/afforestation. Although conversion of forest to pasture for cattle grazing continues, human migration to the United States is likely to affect the trajectory of future land‐use‐land‐cover change.  相似文献   

10.
Water Flows Toward Power: Socioecological Degradation of Lake Urmia,Iran   总被引:1,自引:0,他引:1  
Water is an invaluable resource, and equitable access to it is a fundamental human right. Disenfranchised groups often lose access to water resources because their interests are not well represented by decision makers. Excluding these groups from resource management policy often results in myopic decisions that contribute to further ecosystem damage. We describe the ecological degradation of Lake Urmia in Iran, which has recently experienced increased salinity and declining water quantity. The lake is a UNESCO Biosphere Reserve and Ramsar site, and supports unique biodiversity in the region. The lake's decline is driven by the destruction of Zagros forests and the government's water policies, which diverted water to more politically connected agricultural land users, increasing social inequity and prompting more deforestation. The most straightforward restoration solution is to discontinue the diversions and allow critical inflows to recharge Lake Urmia, preserving the lake and wetlands for migratory birds, tourists, and local communities.  相似文献   

11.
采用综合评价法、聚类分析法、回归相关分析法对福清市土地集约利用的时空变化规律特征进行研究,并对其驱动因素进行深入的分析.研究结果表明:福清市土地集约利用水平具有明显的时空变化规律--1996~2005年土地集约利用水平呈分阶段性上升趋势,1996年和2005年土地集约利用在空间上呈5级分布格局,且空间分布状况变化不大.自然条件是影响土地集约利用最基础的因素,人口、经济、技术因素是造成区域土地集约利用差异的主要原因.同时,解释了土地集约利用的时空变化格局.  相似文献   

12.
太仆寺旗土地利用变化时空格局的动态模拟   总被引:37,自引:4,他引:33  
本文以太仆寺旗为研究区 ,通过将土地利用驱动因子分解为稳定少动控制因子、年际变动影响因子与社会经济驱动因子 ,求解了太仆寺旗土地利用变化驱动因子作用系数矩阵 ,揭示了不同类型因子驱动土地利用变化的方向与强度。在此基础上 ,以CLUE S模型为框架 ,构建了太仆寺旗土地利用变化时空格局模拟模型 ,通过集成基于太仆寺旗土地利用系统动力学模型获取的土地利用变化及其社会经济驱动因子信息 ,动态模拟了太仆寺旗土地利用变化的时空模式 ,进行了参考模式、生态模式与经济模式下的情景分析。  相似文献   

13.
中国北方农牧交错带土地利用变化驱动力的尺度效应分析   总被引:27,自引:2,他引:25  
“可塑性面积单元问题”是对面积数据进行空间统计分析时不可回避的问题。该文以我国北方农牧交错带土地利用变化驱动力研究为契机,探讨了由于“可塑性面积单元问题”的存在而导致的土地利用变化驱动力研究中的尺度效应问题。通过构建土地利用变化驱动力模型,探究了20世纪80年代以来我国北方农牧交错带土地利用变化的驱动机制。研究表明,反映驱动因子与土地利用变化(耕地扩张与草地收缩)关系的Exponent Beta系数随研究尺度的变化而发生显著变化,反映了在研究土地利用驱动力时进行多尺度分析的必要性。  相似文献   

14.
CLUE-S模型应用进展与改进研究   总被引:13,自引:1,他引:12  
土地利用变化是景观生态学重要的研究领域,通过模型模拟土地利用变化趋势是该领域的主要研究内容之一。CLUE-S模型可以全面考虑自然和人文因子,通过迭代方法综合空间分析和非空间分析,较好地模拟小尺度范围内土地利用变化情景,具有综合性、开放性、空间性、竞争效率性等特点,已经在国内外多个地区的土地利用变化研究中得到广泛应用,形...  相似文献   

15.
运用建设用地综合扩展系数分析河南省18个地市建设用地扩展特征及空间差异。在此基础上,利用STIRPAT模型对河南省及其18个地市建设用地扩展的社会经济驱动因素进行定量分析。研究结果表明:河南省18个地市建设用地扩展空间差异显著,扩展变化由弱到强的城市数量和剧烈程度不断增加,整体以郑州为中心的北部、西部城市建设用地扩展变化较为强烈;影响河南省建设用地扩展的因素中,总人口、城镇化水平、公路里程和农村家庭人均纯收入是共性的驱动因素。目前,河南省正处于社会经济迅速发展的时期,应通过提高建设用地的节约、集约利用水平,不断提高建设用地利用效率,最终实现经济可持续发展与土地可持续利用的有机统一。  相似文献   

16.
新疆天山北坡经济带城乡建设用地动态变化的时空特征   总被引:9,自引:2,他引:7  
土地利用变化具有明显的时空特性,是当前国际上开展土地利用/土地覆盖研究的重要内容。通过利用20世纪80年代末和90年代末两个时段的Landsat TM卫星影像,运用GIS空间分析和EXCEL统计分析方法,分析了新疆天山北坡经济带城乡建设用地变化的时空特征及其主要驱动力。结果表明:(1)在这10年的时间里,区域城乡建设用地增长较快,其中特大城市(乌鲁木齐市)和中等城市用地增长迅速。(2)区域城乡建设用地扩张以占用草地和耕地为主。同时,城乡建设用地类型及其结构变化在17市县存在明显的差异。(3)天山北坡经济带城乡建设用地变化是自然和社会经济两大因素共同作用的结果,人口增长、国民经济的增长、工业的发展和政府政策是区域城乡建设用地变化的主要驱动因素。  相似文献   

17.
20世纪90年代中国土地利用变化时空特征及其成因分析   总被引:358,自引:38,他引:320  
在土地利用变化时空信息平台的支持下,本文对我国20世纪80年代末到90年代末的土地利用变化过程进行了全面分析,揭示了我国10年来土地利用变化的时空规律,分析了这些规律形成的主要政策、经济和自然成因。研究表明,20世纪90年代,全国耕地总面积呈北增南减、总量增加的趋势,增量主要来自对北方草地和林地的开垦。林业用地面积呈现总体减少的趋势,减少的林地主要分布于传统林区,南方水热充沛区造林效果明显。中国城乡建设用地整体上表现为持续扩张的态势。90年代后5年总体增速减缓,西部增速加快。20世纪90年代我国的土地利用变化表现出明显的时空差异,政策调控和经济驱动是导致土地利用变化及其时空差异的主要原因。据此,本文提出在今后的全国土地利用规划中,应充分考虑我国现代土地利用变化的区域分异规律。同时,在生态环境恢复与建设规划中也应强调自然地理地带的针对性,同时要改变传统的资源规划与管理思路,在基础设施日益完备的条件下,最大程度地发挥跨区域土地资源优化配置的综合优势  相似文献   

18.
珠海市耕地变化时空特征及其驱动力分析   总被引:2,自引:1,他引:1  
在RS和GIS技术支持下,利用1990、1995、2000和2006年共4期Landsat TM卫星遥感数据,分析珠海市耕地数量和空间变化特征,并探讨耕地动态变化的驱动因子.结果表明:珠海市耕地面积在3个研究时段经历了"快速减少一缓慢增加一急剧减少"的变化过程,人均耕地面积持续减少;2000-2006年耕地的动态度最大,而1995-2000年耕地的动态度相对较小;耕地面积增加的主要来源是水域和林地,减少的去向主要是农业结构调整中耕地转变成水域和建设用地;经济发展、人口增加和农业结构调整是珠海市耕地变化的主导驱动因素,同时政策因素也起到了重要的导向作用.  相似文献   

19.
长江经济带生态用地变化类型识别及驱动因素分析   总被引:1,自引:1,他引:0  
生态用地能够为人们提供生态产品和生态服务,对于维持生态系统健康与安全有着不可替代的作用。在我国城镇化进程快速推进的过程中,生态用地被大量侵占、受损严重,许多土地生态功能丧失。本研究基于1995-2015年的土地利用数据,探究长江经济带生态用地变化时空演变规律,并使用地理探测器和地理加权回归模型对于生态用地变化的驱动机制分别开展全局效应与局部效应分析。本研究将生态用地变化划分为5个类型:严重受损、轻微受损、保持不变、轻微恢复、明显恢复。研究结果表明:1995年至2015年,长江经济带生态用地面积呈现先增加后减少的趋势,但是总体的趋势是减少的,受损面积大于恢复面积。其中,减少的面积主要来自于林地和耕地。在这20年间,从生态用地变化类型来看,保持不变类型的面积最大,其次是轻微受损和轻微恢复类型。生态用地变化是多种因素相互作用的结果,而任何两个驱动因子共同作用的解释力都大于单一的驱动因素。此外,根据地理位置的不同,不同驱动因子对于生态用地变化的影响也不同。本文研究结果有助于土地管理者和政策制定者更好地制定区域和地方的相关土地利用政策。相关经验教训也可以推广到其他地区,以更好地管理生态用地,实现可持续发展。  相似文献   

20.
The potential impact of deforestation in the Brazilian Amazon on greenhouse gas emissions to the atmosphere calls for policies that take account of changes in forest cover. Although much research has focused on the location and effects of deforestation, little is known about the distribution and reasons for the agricultural uses that replace forest cover. We used Landsat TM-based deforestation and agricultural census data to generate maps of the distribution and proportion of four major agricultural land uses throughout the Brazilian Amazon in 1997 and 2007. We built linear and spatial regression models to assess the determinant factors of deforestation and those major agricultural land uses - pasture, temporary agriculture and permanent agriculture - for the states of Pará, Rondônia, and Mato Grosso. The data include 30 determinant factors that were grouped into two years (1996 and 2006) and in four categories: accessibility to markets, public policies, agrarian structure, and environment. We found an overall expansion of the total agricultural area between 1997 and 2007, and notable differences between the states of Pará, Rondônia, and Mato Grosso in land use changes during this period. Regression models for deforestation and pasture indicated that determinant factors such as distance to roads were more influential in 1997 than in 2007. The number of settled families played an important role in the deforestation and pasture, the effect was stronger in 2007 than 1997. Indigenous lands were significant in preventing deforestation in high-pressure areas in 2007. For temporary and permanent agricultures, our results show that in 1997 the effect of small farms was stronger than in 2007. The mapped land use time series and the models explain empirically the effects of land use changes across the region over one decade.  相似文献   

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