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1.
As land use change continues to increase throughout the Amazon basin, there is a pressing need to accurately map, quantify and assess the effects of different factors on forest cover change (FCC). Land tenure may sometimes have important effects on forest cover, yet such effects remain poorly understood in Amazonia, particularly outside Brazil. In this paper we assess whether significant differences in trends of FCC can be partially explained by different land tenure arrangements, using a case study in southwestern Beni (Bolivian Amazon). We examine spatio-temporal dynamics of FCC across four land tenure systems (indigenous titled territory, protected area, logging concession, and private land) by classifying forests using a time-series of Landsat satellite imagery consisting of four dates (1986, 1996, 2001, 2009). Specifically, we unravel (1) trends in early growth and old-growth forest extent, including changes in total cover area, annual change rates, and spatial change dynamics, and (2) trends in old-growth forest fragmentation. To better understand the association between land tenure and FCC, we qualitatively assess the potential role that other underlying and proximate drivers may have had in FCC over the study period. We found that private lands underwent, by far, the largest FCC, that indigenous territories and the protected area had little FCC, and that logging concessions were responsible for the lowest FCC. Our findings suggest that land tenure played a key role in FCC except in private areas, where many other drivers had operated. Our study sheds light into the potential role of land tenure in FCC and has important implications for public policies aimed at socioeconomic development and environmental conservation in the Amazon. We give some policy recommendations drawn from a biocultural conservation perspective that could contribute to implement more inclusive conservation policies in the region.  相似文献   

2.
Africa's Albertine Rift region faces a juxtaposition of rapid human population growth and protected areas, making it one of the world's most vulnerable biodiversity hotspots. Using satellite-derived estimates of forest cover change, we examined national socioeconomic, demographic, agricultural production, and local demographic and geographic variables, to assess multilevel forces driving local forest cover loss and gain outside protected areas during the first decade of this century. Because the processes that drive forest cover loss and gain are expected to be different, and both are of interest, we constructed models of significant change in each direction. Although rates of forest cover change varied by country, national population change was the strongest driver of forest loss for all countries – with a population doubling predicted to cause 2.06% annual cover loss, while doubling tea production predicted to cause 1.90%. The rate of forest cover gain was associated positively with increased production of the local staple crop cassava, but negatively with local population density and meat production, suggesting production drivers at multiple levels affect reforestation. We found a small but significant decrease in loss rate as distance from protected areas increased, supporting studies suggesting higher rates of landscape change near protected areas. While local population density mitigated the rate of forest cover gain, loss was also correlated with lower local population density, an apparent paradox, but consistent with findings that larger scale forces outweigh local drivers of deforestation. This implicates demographic and market forces at national and international scales as critical drivers of change, calling into question the necessary scales of forest protection policy in this biodiversity hotspot. Using a satellite derived estimate of forest cover change for both loss and gain added a dynamic component to more traditionally static and unidirectional studies, significantly improving our understanding of landscape processes and drivers at work.  相似文献   

3.
环渤海地区土地利用变化的驱动力分析   总被引:105,自引:15,他引:105  
朱会义  何书金  张明 《地理研究》2001,20(6):669-678
1985到1995年间,环渤海地区占总面积30%的土地发生了利用方式的变化,耕地变化是其核心类型。耕地变化的主要流向依次为农村居住用地、林草地、城市居住建设用地以及果园和水域。本文通过对耕地流向及其与人口变化、农业经济发展的关系等进行分析,确认土地管理政策、人均居住用地的增长、农业生产结构调整以及城市扩张是该区土地利用变化的主要驱动因素  相似文献   

4.
地理环境因素对伊洛河流域森林景观的影响   总被引:11,自引:2,他引:9  
丁圣彦  梁国付 《地理研究》2007,26(5):906-915
地理环境因素是引起区域森林景观动态变化的主要原因。运用景观生态学的基本原理,借助于地理信息系统技术,分析了自1983年以来伊洛河流域洛宁县森林景观的动态变化。结果显示,森林景观类型总面积呈增加趋势,从1983年的960.34km2增加到1999年的1175.00km2。景观空间动态变化上,森林景观类型转化为非森林景观类型部分主要位于海拔500~1000m的低山区,海拔大于1000m的地区森林景观类型变化较小,而非森林景观类型转化为森林景观类型主要集中在海拔高度小于500m的塬陵区和川涧区。通过建立森林景观类型动态变化与相应高程、坡度、距离居民点中心的远近和与森林边缘距离之间的相互关系,分析了与上述地理环境因素之间的相关性,表明森林景观类型动态变化与上述地理环境因素之间有显著相关关系。  相似文献   

5.
黄土沟壑区小流域土地利用变化及驱动力分析   总被引:11,自引:0,他引:11  
小流域综合治理是黄土高原减少土壤侵蚀和发展经济的成功经验。作为黄土高原沟壑区的典型代表,王东沟流域的土地利用变化反映了流域治理的过程。利用其1986、1994和2004年的土地利用数据,研究了该区18 a间的土地利用变化规律,探究土地利用变化的驱动力,并使用GM(1,1)灰色模型对王东沟流域未来的土地利用变化趋势进行了分析。结果表明:1986~2004年间王东沟流域各土地利用类型变化的面积大小依次是农地>果园>林地>非生产地>草地,就土地利用类型的变化速度而言,依次为果园>农地>林地>非生产地>草地;以1994年为界将1986~2004年划分为两个时期,两个时期的土地利用变化规律有所不同;利用矢量图叠加,发现1994~2004年流域45.48%的土地发生了土地类型的变化,土地利用变化类型主要有9种,农地转出的类型和林地转入的类型占多数;社会经济驱动、人为积极治理和政策导向是王东沟流域土地利用变化的主要驱动力;GM(1,1)趋势分析表明在今后一段时间内,影响因子不变的前提下,果园面积仍有增加趋势,农地面积需要进行人工调控以保持一定的规模。  相似文献   

6.
Understanding and analysis of drivers of land-use and -cover change (LUCC) is a requisite to reduce and manage impacts and consequences of LUCC. The aim of the present study is to analyze drivers of LUCC in Southern Mexico and to see how these are used by different conceptual and methodological approaches for generating transition potential maps and how this influences the effectiveness to produce reliable LUCC models. Spatial factors were tested for their relation to main LUCC processes, and their importance as drivers for the periods 1993–2002 and 2002–2007 was evaluated by hierarchical partitioning analysis and logistic regression models. Tested variables included environmental and biophysical variables, location measures of infrastructure and of existing land use, fragmentation, and demographic and social variables. The most important factors show a marked persistence over time: deforestation is mainly driven by the distance of existing land uses; degradation and regeneration by the distance of existing disturbed forests. Nevertheless, the overall number of important factors decreases slightly for the second period. These drivers were used to produce transition potential maps calibrated with the 1993–2002 data by two different approaches: (1) weights of evidence (WoE) to represent the probabilities of dominant change processes, namely deforestation, forest degradation, and forest regeneration for temperate and tropical forests and (2) logistic RM that show the suitability regarding the different land-use and -cover (LUC) classes. Validation of the transition potential maps with the 2002–2007 data indicates a low precision with large differences between LUCC processes and methods. Areas of change evaluated by difference in potential showed that WoE produce transition potential maps that are more accurate for predicting LUCC than those produced with RM. Relative operating characteristic (ROC) statistics show that transition potential models based on RM do usually better predict areas of no change, but the difference is rather small. The poor performance of maps based on RM could be attributed to their too general representation of suitability for certain LUC classes when the goal is modeling complex LUCC and the LUC classes participate in several transitions. The application of a multimodel approach enables to better understand the relations of drivers to LUCC and the evaluation of model calibration based on spatial explanatory factors. This improved understanding of the capacity of LUCC models to produce accurate predictions is important for making better informed policy assessments and management recommendations to reduce deforestation.  相似文献   

7.
以2015年土地利用类型数据为基础,计算长江中下游流域人类活动强度,采用最邻近指数、地理集中指数和不均衡指数分析研究区自然保护区、风景名胜区等六类国家级自然保护地分布特征,并定量揭示保护地空间分布与人类活动强度的关系,旨在为长江中下游流域建立基于人类活动强度的各类自然保护地管控策略提供科学依据。结果表明:1)人类活动高、较高、中、较低和低强度带在研究区的占比分别为3.74%、9.83%、14.98%、30.81%和40.63%;高等级强度带主要分布在长江三角洲平原、江汉平原等平原区,低等级强度带主要分布在秦岭山区、武陵山区等山地丘陵区。2)湿地公园、森林公园、风景名胜区和地质公园的空间分布类型为均匀型,水利风景区和自然保护区为凝聚型;六类保护地在各人类活动强度带空间分布不均衡。3)湿地公园、森林公园、水利风景区、自然保护区、风景名胜区和地质公园分别在中、较高、高、低、较低和低强度带密度最大;在高等级强度带“人地”矛盾更突出,应加强对自然保护地的保护力度和人类活动管控,尤其针对湿地公园、森林公园和水利风景区。  相似文献   

8.
土地利用/覆盖变化是全球变化研究的重要问题,而海岸带则是该领域研究的热点区域。以三套土地利用/覆盖数据(MCD12Q1、CCI-LC和GlobeLand30)为基础,采用基于一致性分析和模糊集合理论的数据融合方法,获取2000年和2010年亚欧大陆中低纬度海岸带土地利用/覆盖分类信息,进而分析土地利用/覆盖变化特征及驱动因素。结果表明:十年间亚欧大陆中低纬度海岸带土地利用/覆盖变化方式主要以耕地萎缩和林地扩张为主,其次是湿地扩张,再次是草地和裸地萎缩,最后是灌木地和人造地表扩张;土地利用/覆盖类型之间的相互转换面积较小,仅占研究区总面积的4.22%,其中分布面积占优势的变化类型为耕地–林地–草地相互转换、灌木地–裸地相互转换、林地转为湿地以及林地转为灌木地等。地形因素、气候分异等自然驱动力深刻影响着土地利用/覆盖变化的宏观格局,而人口压力增大、经济高速发展、政策的颁布与实施等人文驱动力则是推动十年间亚欧大陆中低纬度海岸带土地利用/覆盖变化的主要原因。  相似文献   

9.
中国典型自然保护区生境状况时空变化特征   总被引:17,自引:1,他引:16  
祝萍  黄麟  肖桐  王军邦 《地理学报》2018,73(1):92-103
中国已建立各类自然保护区2740个,占全国陆地面积的14.8%。本文以典型国家级自然保护区为例,基于遥感反演、模型模拟、空间分析等方法,获得植被覆盖度、净初级生产力(NPP)和土地覆被时空数据集,分析2000-2015年中国不同区域、不同类型自然保护区生境状况时空变化及人类扰动的影响,进而评估自然保护区在栖息地及生物多样性保护方面的效果。结果表明:2000-2015年,国家级自然保护区植被覆盖度从36.3%提高到37.1%,各类型自然保护区均有不同程度提高,其中森林类保护区年增速0.11%,草原草甸类0.84%,内陆湿地类0.21%,荒漠生态类0.09%,野生动物类和野生植物类则分别为0.11%和0.08%。草原草甸类、内陆湿地类、荒漠生态类、野生动物类自然保护区植被NPP年增速分别为2.06 g·m-2、1.23 g·m-2、0.28 g·m-2、0.4 g·m-2,而森林类和野生植物类则分别以3.45 g·m-2和2.35 g·m-2的年速率减少。近15年,国家级自然保护区内人类扰动呈现微弱变化,除青藏高原区和南亚热带湿润区内保护区人类扰动略微下降以外,其他区域均有所增强,特别是北亚热带和温带湿润区,其保护区人类扰动由4.70%明显增至5.35%。  相似文献   

10.
以金花茶国家级自然保护区及保护区外2 km邻近区为研究区,选取1986―2019年7期Landsat遥感影像进行土地利用遥感解译,并基于GIS与R语言空间统计方法分析近35年土地利用动态演变规律。结果表明:1)保护区土地利用以林地为主,邻近区林地和耕地面积占比最大。2)邻近区综合土地利用动态度变化比非核心区更剧烈;二者土地利用程度综合指数变化均呈现升高-降低-不变的波动趋势,表明保护区建立后人为干扰的下降有助于土地利用格局的稳定。3)土地利用类型转换频率为邻近区向非核心区递减,表明保护区的建设与管理可以有效保护当地的生态环境。4)保护区非核心区所有土地利用类型重心总体上向东北方向迁移;邻近区建设用地与耕地重心总体上都为向西方向迁移,表明已有建设用地扩张对保护区周围的土地利用空间动态变化有重要影响。5)保护区的管理取得较为显著的成效,保护区内部生态环境得到改善,但内部建设用地的缓慢增加与资源的不合理生产开发,仍然对保护区的生境质量产生负面影响。  相似文献   

11.
21世纪初中国土地利用变化的空间格局与驱动力分析   总被引:99,自引:5,他引:94  
在全球环境变化研究中.以土地利用与土地覆盖动态为核心的人类一环境耦合系统研究逐渐成为土地变化科学(LCS)研究的新动向.基于覆盖中国21世纪初5年间隔的遥感卫星数据获取的1 km网格土地利用变化空间信息.依据近5年土地利用变化区域分异的显著特征,以及自然地理、经济发展与国家宏观政策因素综合考虑.设计针对21世纪初5年新的中国土地利用动态区划图,揭示土地利用变化的空间格局与驱动因素.总体上.21世纪初5年中国处于土地利用快速变化期,黄淮海平原、东南沿海地区与四川盆地城乡建设用地显著扩张,占用大规模优质农田,导致南方水田面积明显减少:西北绿洲农业发展与东北地区开垦导致北方旱地面积略有增加:受西部开发"生态退耕"政策的影响中西部地区林地面积显著增加,国家退耕还林还草政策成效明显,对区域土地覆盖状况的改善产生积极的影响:这一时段国土开发与区域发展战略的实施,包括"西部大开发"、"东北振兴"等国家重大政策,加之快速的经济发展是该阶段土地利用变化格局形成的主要驱动因素.  相似文献   

12.
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the “Grain for Green” policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of “Western Development”, “Revitalization of Northeast”, coupled with rapidly economic development during this period.  相似文献   

13.
21世纪初中国土地利用变化的空间格局与驱动力   总被引:33,自引:15,他引:18  
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period.  相似文献   

14.
Sudden and gradual land use changes can result in different socio-ecological systems, sometimes referred to as regime shifts. The Lao PDR (Laos) has been reported to show early signs of such regime shifts in land systems with potentially major socio-ecological implications. However, given the complex mosaic of different land systems, including shifting cultivation, such changes are not easily assessed using traditional land cover data. Moreover, regime shifts in land systems are difficult to simulate with traditional land cover modelling approaches. A novel simulation approach was employed that focused on simulating changes in land systems rather than focusing on land cover. With the CLUmondo model we simulated three scenarios of potential developments between the years 2010 and 2030 assuming different degrees of international market integration and sustainable growth objectives. Although all scenarios show a decline of shifting cultivation systems, the respective orientation of markets and land governance resulted in strongly different land change trajectories. The land system changes are strongly location dependent and different trajectories are found in different parts of the country. Some scenarios show clear elements of land sparing with intensification of land management in the valleys and re-growth of forest on sloping land. Other scenarios show elements of enhanced multi-functionality. The approach addressed methodological challenges in simulating land system regime shifts and complex mosaic landscapes while accounting for societal demands for different types of goods and services from land systems. The land systems approach allows a nuanced representation of different types of forests and agricultural systems such as shifting cultivation and commercial agricultural plantations. Simulation results contribute to a debate about desired future land use on the national scale including its environmental and socio-economic implications.  相似文献   

15.
Traditional land use systems are threatened by land use intensification and resulting land cover transitions in northern areas. This article examines cumulative land cover changes and their impacts on reindeer grazing grounds in the Kyrö reindeer herding district in northern Finland. Land cover transitions were studied using Landsat TM and OLI images and topographic maps. The results showed that the herding district has experienced notable land cover changes during the past decades, and most of these changes were directly related to forestry. The proportion of continuous coniferous forests of the total forest cover declined from 92% to 78% between 1987 and 2013. Approximately one third of the forests outside current conservation areas were disturbed by forest management by 2013, and remaining forests were notably more fragmented than forests within conservation areas. The extent of the road and path networks expanded considerably between 1960s and 2010 as a result of increasing logging and tourism. Accumulation of disturbances gradually results in loss of key resources and declined quality of the landscape mosaic from the reindeer herding perspective, which can pose a serious threat to long-term sustainability of the livelihood. Rapid land cover changes in non-protected areas highlight an increasingly important role of conservation areas in maintaining resources for reindeer husbandry in the face of intensifying land use. Sustainable management of resources outside conservation areas requires careful participatory planning and efficient cumulative impact assessment of different land use activities.  相似文献   

16.
1960-2010 年贵州省喀斯特山区陡坡土地利用变化   总被引:6,自引:0,他引:6  
基于GIS 与RS技术, 以贵州省喀斯特山区坡度大于25°的区域为研究对象, 利用1960 年1:50000 地形图、1990 年Landsat TM遥感影像以及2010 年的环境减灾卫星(HJ-1A/1B)影像, 解译获取1960、1990、2010 年3 个时间点的土地利用数据, 并结合贵州省水文地质图、坡度图进行陡坡土地利用变化分析。结果表明:①1960-1990 年的30 年间, 有林地、灌木林、水体呈减少趋势, 其中灌木林减少的最多, 其次是有林地;而草地、建设用地、裸岩和耕地呈持续增长趋势, 其中草地增加的最多, 其次是耕地。②1990-2010 年的20 年间, 灌木林、裸岩、耕地呈减少趋势, 其中耕地减少的最多;而有林地、疏林地、草地、水体呈增长趋势, 其中疏林地增加的最多。③随坡度增加覆盖比例呈降低趋势的土地利用类型为有林地、疏林地、水体、建设用地和耕地;随坡度增加覆盖比例呈增加趋势的土地利用为灌木林、草地和裸岩。  相似文献   

17.
中国国家级自然保护区人类活动及变化特征   总被引:2,自引:0,他引:2  
自然保护区是中国自然保护地的基础,是生物多样性保护的核心区域,国家级自然保护区更是中国自然保护区的主体。基于高分辨率影像数据,提取了中国446个国家级自然保护区2015年的人类活动及2013—2015年人类活动变化信息,分不同功能区、不同人类活动、不同区域和不同类型国家级自然保护区分析了人类活动及变化情况,并评估了2013—2015年人类活动变化强度和规律,结果表明:2015年,446个国家级自然保护区人类活动普遍存在,以农业用地和居民点占绝对优势,这两种类型人类活动总面积占国家级自然保护区人类活动总面积的88.94%、总数量占77.67%。2013—2015年,有66.59%的国家级自然保护区存在新增或规模扩大人类活动,人类活动数量增幅达到2.45%,相较于农业用地和居民点,开发建设活动的新增或规模扩大趋势更为明显。2013—2015年,33.41%的国家级自然保护区人类活动无变化,45.06%的国家级自然保护区人类活动变化较小,仅有21.53%的国家级自然保护区人类活动变化明显和较明显。从空间分布看,总体上东部的国家级自然保护区比中西部的国家级自然保护区人类活动变化强度大,沿海、沿河国家级自然保护区人类活动变化强度相对较大。  相似文献   

18.
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   

19.
利用GIS和Logistic回归分析方法,在分析千岛湖镇1993~2004年土地利用变化特征的基础上探讨其变化的驱动力,揭示了千岛湖镇土地利用的时空分异特征。结果表明:土地利用变化以城镇及工矿用地的输入和林地的输出为主要特点;耕地、林地、未利用地和其它未利用地的转出面积超过转入面积,而园地、其它农用地、交通用地、水利设施用地和城镇及工矿用地则相反;自然因素、城镇化、农业结构调整、比较经济利益、交通条件和政策因素是引起其土地利用变化的主要驱动力因子,距一级干道的距离是最重要的自然驱动因子。  相似文献   

20.
土地变化模型方法综述   总被引:3,自引:2,他引:1  
土地系统变化长期以来不仅是地理学研究热点,也是资源环境经济学、生态学、城市规划等多学科领域关注的主题。构建模型模拟土地变化能够促进理解人地相互作用机制,模拟结果可为土地资源优化与资源环境政策制定提供依据。不同研究者基于不同学科理论、应用多种方法构建土地变化模型,模型从早期关注自然覆被类型变化发展到对人类决策行为的刻画,从统计方法发展到更突出空间分布的元胞自动机方法,以及更聚焦土地变化过程的经济学方法和多主体方法。未来土地变化模型发展方向为:在多尺度进行多方法耦合,对土地变化过程进行更为明晰地刻画,将土地变化模型与其他地球系统模型耦合等方面,进一步能够促进解释复杂人地系统,并推进模型在决策支持层面的应用。  相似文献   

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