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1.
驱动力分析是土地利用研究的重要内容。选择怒江流域北段高黎贡山自然保护区周边4个自然村为研究对象,应用高分辨率SPOT 5遥感影像数据,结合实地逐块核实,对土地利用/覆被进行分类,并建立土地利用类型分类系统,用Fragstats 33分析得到村域土地利用格局和特征;同时,采用入户调查、半结构访谈和问卷调查等方法,获得的村域详细社会经济数据,建立土地利用与社会经济之间的关联,分析村域土地利用的驱动力。结果显示:村域土地利用主要受自然条件、受教育程度、生活习俗等因子的驱动,且经济收入主要依赖于粗放的土地利用。研究结果能为怒江云南北段的土地资源合理利用和村域经济发展提供数据支持;研究方法可作为局域尺度土地利用研究的参考  相似文献   

2.
Land use and cover conversions as well as climatic factors drive current and future threats to freshwater systems. Research from the United States and across the globe has focused on already threatened and degraded freshwater systems, whose recovery requires significant investments. Attention must also be directed to monitoring freshwater systems that may appear robust, yet are likely to face enhanced vulnerabilities in the future due to climate and land use and cover changes. Such proactive monitoring can help identify problems early and provide potential solutions. In this study, we consider the case of Sebago Lake and its watershed in southern Maine; a region that has experienced significant population growth and development activity. Land use, socioeconomic change and water quality trends are monitored over a 20-year period using Landsat imagery, census, water quality and precipitation data. Our results indicate that Developed Land within the watershed has increased from 5.4 % of the total land area in 1987 to 8.9 % in 2009 with associated increases in population and housing activity. Sebago Lake’s water quality indicators from 1990 to 2010 show a directional trend concomitant with this change. The increase in Developed Land is likely to place additional pressures on water quality in the future. The analysis also indicates that precipitation trends play an important role in water quality variability for Sebago Lake. Predicted changes to climatic factors including enhanced spring time precipitation or earlier ice-out conditions combined with further land use change may play an influential role in determining water quality. The analysis highlights emerging areas of concern and reiterates the essential role of proactively monitoring vulnerable systems to help mitigate future threats.  相似文献   

3.
A study was conducted to investigate hydrological impacts of land cover changes in the degradation of the hydrological on flow regimes of the Upper Shire river, Malawi. Remote sensing techniques were used to inventory temporal changes of land cover changes in the catchment. Hydrological data were analyzed to reveal the alterations and trends for two periods; 1989 and 2002. The study revealed significant changes in magnitude and direction that have occurred in the catchment between 1989 and 2002, mainly in areas of human habitation. Trends in land cover change in the Upper Shire river catchment depict land cover transition from woodlands to mostly cultivated/grazing and built-up areas. The land cover mapping showed that 23% of the land was covered by agricultural land in 1989. Subsistence agricultural area has increased by 18%, occupying 41% of the study area in 2002. The effects of the derived land cover changes on river flow in the Upper Shire river were investigated using the semi distributed soil and water assessment tool (SWAT) model. River flows were found to be highly variable and sensitive to land cover changes. Simulation results show that 2002 land cover data produces higher flow peaks and faster travel times compared to the 1989 land cover data. The changes detected indicate the effects of land use pressure in the catchment. The study highlights the importance of considering effects of land use and land cover changes on ecosystems, and water resources for an informed decision on proper catchment planning and management.  相似文献   

4.
The drastic socio-economic and political changes that occurred after the breakdown of socialism in Eastern Europe triggered widespread land use change, including cropland abandonment and forest cover changes. Yet the rates and spatial patterns of post-socialist land use change remain largely unclear. We used Landsat TM/ETM+ images to classify land cover maps and assess landscape pattern changes from 1990 to 2005 in Argeş County, Southern Romania. Cropland abandonment was the most widespread change (21.1% abandonment rate), likely due to declining returns from farming, tenure insecurity, and demographic developments during transition. Forest cover and forest fragmentation remained remarkably stable during transition, despite widespread ownership transfers. Cropland abandonment provides opportunities for increased carbon sequestration, but threatens cultural landscapes and biodiversity. Continued monitoring is important for assessing whether abandoned croplands will eventually reforest or be put back into production and to better understand the consequences of post-socialist land use change for ecosystems and biodiversity.  相似文献   

5.
土地利用/覆被变化(LUCC)对流域水文过程具有重要的长期影响作用。针对土地利用覆被变化对大型流域水文过程的影响程度,利用构建的长江流域分布式水文模型分析了土地利用变化情景下的水文效应特征。结果显示:分布式水文模型综合考虑了下垫面土壤、坡度、植被等特征,可以较好的反映降水发生后水分在不同土壤、植被和地形条组合件下,蒸散、地表和地下径流等组分的运移过程。根据不同土地覆被类型的径流成分差异,以及长江流域实际可供调节的土地利用方式,流域现有土地利用格局中农林地依然具有较大的转换空间。根据典型流域中预设的农林地转换情景下的径流效应看,各种情景虽然对流域径流总量变化影响较小,但对蒸散、地表径流和基流可以产生显著影响。其中,林地增加使基流最高提升超过15%,同时可使地表径流下降近5%,两者对蒸散的改变在1%左右,对径流总量变化幅度则只有0.7%左右。不同情景下的水文响应模式反映了未来土地利用调整的水文效应,因此可以基于不同的径流效应,开展有利于综合发挥流域持水能力的空间规划,提升林地所占比重。  相似文献   

6.
土地利用变化对生态系统服务的影响研究综述   总被引:9,自引:0,他引:9  
土地利用/覆被变化是全球环境变化的重要组成部分和主要原因之一,不仅带来了地表结构的巨大变化,而且对生态系统服务也造成重要影响。土地利用变化和生态系统服务研究已成为国际上生态学和地理学等跨学科研究的热点之一。从土地利用变化和生态系统服务的概念及其影响因素分析入手,综述了土地利用面积变化、土地利用方式变化和土地利用空间格局变化等对生态系统服务的影响,归纳了土地利用变化对生态系统服务的影响研究的主要方法和模型,分析了相关研究的不足,并提出了加强生态系统服务动态评估方法和时空动态评估模型的研究、强化土地利用变化对生态系统服务影响的生态学机制研究和注重土地利用变化下生态系统服务评估结果的集成应用研究等建议,以期对我国的土地利用变化与生态系统服务评估研究提供科学参考。  相似文献   

7.
Land use change is the main driving force of global environmental change and is considered as very central to the ongoing debate on sustainable development. Even though large volume of literature materials is available of land use/land cover (LU/LC) change for many areas, very little is known of it in the floodplain of the Sokoto Rima River Basin of Nigeria despite the basin’s strategic importance. Thus, this study characterized the basin’s LU/LC and its change using computer-based digital classification of near-anniversary Landsat 5 TM imagery of November 23, 1998, and Landsat 8 OLI of December 2, 2013. The results of the digital classification were complimented with field-based observations on major observable characteristics of every LU/LC identified. Thirteen classes (forest area, dense grassland, grassy fallow, grazed open grassland, open cultivation, open grain fallow farmland, pepper cultivation, rice farmland, scrubland, sugarcane farmland, dry bare land, sand deposit and wetland/water) were characterized and the nature and extent of their changes assessed. 40 % of the basin’s uses is under cultivation, 22 % is under fallow, 27 % is either degraded or non-cultivable, while 11 % is forested. Change events include forest loss, increase in area cultivated, expansion of shrub/scrubland and pervasiveness of grazing. The changes were more pronounced in the upper than either the central and southern segments of the basin. In general LU/LC changes in the basin are reflection of increased human population pressure and effects of climate change. The LU/LC patterns and changes suggest underutilization and mismanagement of the floodplain which have impact on soil, hydrology and biodiversity with serious implication for livelihood and food security. The study recommends that interventions are needed to promote enhanced and sustainable management of land, water and vegetation resources in the basin, with particular emphasis on empowering the local land users to participate actively toward sustainable management of the floodplain.  相似文献   

8.
Land use and land cover change (LUCC) has emerged as an important issue of global change with significant influences on the geochemical cycle and regional climate change. Understanding the historical changes of land use and analyzing the environmental effects of LUCC make such reconstructions important. Based on historical statistics, this article reconstructs cropland area at the municipality level (härad/kommun) in the Scandinavian Peninsula during 1875–1999. The total acreage of cropland increased 36.84 % during 1875–1930, kept stable during 1930–1950, and decreased 14.25 % during 1950–1999. The croplands of Sweden and Norway both increased before 1950 and changed in different ways during 1950–1999 when the cropland decreased by 19.79 % in Sweden but increased by 9.63 % in Norway. The counties in the south Scandinavian Peninsula owned most of the cropland, with a cropland proportion of over 20 %, and experienced relatively obvious cropland changes. Growth centers with a rate of increase of over 5 % during 1875–1910 were found in Skåne, Stockholm, the Uppsala counties in Sweden, and the area around Oslo county in Norway. The general cropland distribution showed almost no change during this period, which mainly reflects the suitability of the natural conditions for agriculture. Multi-social factors co-impacted land use activities and induced temporal and spatial variations of the cropland. These factors included food supply, world trade, wars, agriculture policies, the economic and political environment, urbanization, and national differences. Compared with the widely used global land use dataset Historical Database of the Global Environment (HYDE), this study shows different cropland change curves before 1950. This article is a case study showing that the hindcasting model of the HYDE dataset has difficulty estimating multi-determined cropland change in the Scandinavian Peninsula, and the empirical study contributes to the improvement of the accuracy of historical land use data at the regional level.  相似文献   

9.
The present research investigated the relationship between nitrate–nitrogen (NO3–N) in river water and the land use/land cover (hereafter, land use) in the Teshio River watershed located in northern Hokkaido island to understand the effect of human activities such as agriculture, forestry, industry, and urbanization in the drainage basin on the river ecosystem quality and services. River water was sampled at nine points seasonally during a 2-year period and the nutrients concentration was measured. Land use profiles were estimated at two spatial scales, riparian and sub-catchment, for each sampling station. The spatial pattern of water quality in the Teshio River showed increased NO3–N levels associated with agriculture and urban expansion, and forest reduction in the watershed. Land use at the riparian scale closely reflected that at the sub-catchment scale, which masked the unique riparian buffer effect on the river water condition. The increased agricultural and reduced forest area in the riparian zone, especially in the upper middle reach, could be a possible reason for a decline of ecosystem service for the provisioning of clean water and habitat for aquatic organisms. Measures towards sustainable and more nature-friendly agricultural management are necessary in the area to protect the Teshio River ecosystem and its ecosystem services.  相似文献   

10.
Urban consumption of ecosystems services such as food generates environmental impacts at different geographical scales. In the last few decades Tokyoites have shown an increasing appetite for meat. This study examines the environmental implications of Tokyo’s increasing meat consumption by analyzing how this trend has affected land use and cover change in areas near and far away. Historical databases (1970–2005) are employed in order to explore meat consumption patterns in Tokyo and to relate it with beef and pork production in areas within the country and abroad. It also integrates the historical analysis of production and consumption patterns with a discussion of the drivers (e.g., wealth, price, policies and seafood availability) behind these trends. We identified that meat production in Japan followed three distinct phases between 1877 and 2005. In the first period it took 50 years for production to increase by 50%, while during the next phase production showed the same growth in just half the time. Major changes in land use/cover change because of domestic meat production occurred mainly during the second phase and, thereafter, when domestic production declined and was substituted to a great extent by imports. Despite the increasing consumption of imported meat, Tokyo relies greatly on domestic meat produced in its neighboring prefectures. The paper concludes that regional planning can be used as an effective instrument to protect the environment and secure protein for the population of mega-urban areas such as Tokyo.  相似文献   

11.
Environment, Development and Sustainability - Land use and land cover (LULC) changes, climate variability and climate change (CC) contribute hydrological response in tropical catchments, but their...  相似文献   

12.
Land change science has emerged as a fundamental component of global environmental change and sustainability research. Still, much remains to be learned before scientists can fully assess future roles of land-use/cover changes (LUCC) in the functioning of the Earth system and identifying conditions for sustainable land use. The objective of this paper is to gain a better understanding of the complex interactions of human and natural drivers underlying LUCC. We do so by developing and estimating a novel structural model of land use and using spatially explicit longitudinal observations from the Upper Yangtze basin of China. Our analysis focuses on the multiple dimensions of agriculture—not only cropland use itself, but also grain production, soil erosion, and related technical change—and our data cover 31 counties over four time periods from 1975 to 2000. Our results show that technical change plays an important role in supplying food on a limited cropland; limiting cropland expansion in turn reduces soil erosion, which then benefits grain production in the longer term. It is also found that policies and institutions have significant impacts on land use and the status of soil erosion. Together, these results carry some great implications to sustainable land use and ecosystem management.  相似文献   

13.
Land degradation is one of the serious environmental problems that can lead to poverty, and is especially prominent in eco-fragile areas in developing countries and increases the risk of environmental safety. North Hebei Province belongs to an ecologically fragile region in North China, which has great impact on the eco-safety of Beijing and Tianjin. Using Landsat TM data and GIS, this paper evaluates land degradation in North Hebei province of China from the the 1960's to 1987 and 2000. Land use/cover change pattern from 1987 to 2000, its regional difference and forest change characteristics will also be analyzed; soil erosion intensity and arable land suitability were also evaluated. Results revealed that land use/cover pattern in this study area did not change greatly from 1987 to 2000. The structure and function of regional land ecosystem was at a level of local improvement and integral deterioration. Land above medium soil erosion intensity reached 21 percent, which was also the area with a serious soil erosion and land degradation problem. Soil erosion and land degradation intensity of grassland was the biggest. For the present arable land, the proportion of high suitability was 13 percent.  相似文献   

14.

This study examined the effects of transhumance pressure on total abavoe-ground biomass and forage availability on rangelands in Benin. We also investigated the implications of land cover transitions on rangelands over a 31-year period. Our work was carried out in three regions of Benin representing distinct phytogeographic regimes: Ketou, Tchaourou, and Sinende. Ground-truthing and biomass sampling of the herbaceous and phanaerophyte strata were carried out between the 2016 peak vegetation period and the onset of the 2017 rainy season. Herbaceous biomass was determined by destructive sampling, and biomass of shrub and trees was estimated using non-destructive sampling and allometric equations. Historical and present-day Landsat data allowed an analysis of land cover change for the 1986–2002 and 2002–2017 periods. Land cover analyses yielded evidence of significant expansion of agricultural areas, especially in the latter period. The data also revealed progressive landscape fragmentation and transformations to a land cover of reduced total phytomass. There were no long-term effects of transhumance on trees, but likely on herbaceous biomass. Land cover changes in the study regions seem primarily the result of population pressure, infrastructural changes, persisting norms, and traditions regarding environmental management and the increasing popularity of livestock keeping as an insurance strategy. Rangeland transformations had negative impacts on transhumant herds’ mobility and forage availability. As rangeland stability and consent between agricultural and pastoral land users are at a tipping point, informed policies, and land use planning that foster compromises among all stakeholders are needed.

  相似文献   

15.

Explorations of future land use change are important to understand potential conflicts between competing land uses, trade-offs associated with particular land change trajectories, and the effectiveness of policies to steer land systems into desirable states. Most model-based explorations and scenario studies focused on conversions in broad land use classes, but disregarded changes in land management or focused on individual sectors only. Using the European Union (EU) as a case study, we developed an approach to identifying typical combinations of land cover and management changes by combining the results of multimodel simulations in the agriculture and forest sectors for four scenarios from 2000 to 2040. We visualized land change trajectories by mapping regional hotspots of change. Land change trajectories differed in extent and spatial pattern across the EU and among scenarios, indicating trajectory-specific option spaces for alternative land system outcomes. In spite of the large variation in the area of change, similar hotspots of land change were observed among the scenarios. All scenarios indicate a stronger polarization of land use in Europe, with a loss of multifunctional landscapes. We analyzed locations subject to change by comparing location characteristics associated with certain land change trajectories. Results indicate differences in the location conditions of different land change trajectories, with diverging impacts on ecosystem service provisioning. Policy and planning for future land use needs to account for the spatial variation of land change trajectories to achieve both overarching and location-specific targets.

  相似文献   

16.
Understanding patterns, dynamics, and drivers of land use is crucial for improving our ability to cope with sustainability challenges. The human appropriation of net primary production (HANPP) framework provides a set of integrated socio-ecological indicators that quantify how land use alters energy flows in ecosystems via land conversions and biomass harvest. Thus, HANPP enables researchers to systematically and consistently assess the outcome of changes in land cover and land-use intensity across spatio-temporal scales. Yet, fine-scale HANPP assessments are so far missing, an information important to address site-specific ecological implications of land use. Here, we provide such an assessment for Europe at a 1-km scale for the years 1990, 2000, and 2006. The assessment was based on a consistent land-use/biomass flow dataset derived from statistical data, remote sensing maps, and a dynamic global vegetation model. We find that HANPP in Europe amounted to ~43 % of potential productivity, well above the global average of ~25 %, with little variation in the European average since 1990. HANPP was highest in Central Europe and lower in Northern and Southern Europe. At the regional level, distinct changes in land-use intensity were observed, most importantly the decline of cropland areas and yields following the breakdown of socialism in Eastern Europe and the subsequent recovery after 2000, or strong dynamics related to storm events that resulted in massive salvage loggings. In sum, however, these local dynamics cancelled each other out at the aggregate level. We conclude that this finding warrants further research into aspects of the scale-dependency of dynamics and stability of land use.  相似文献   

17.
Abstract

Land degradation is one of the serious environmental problems that can lead to poverty, and is especially prominent in eco-fragile areas in developing countries and increases the risk of environmental safety. North Hebei Province belongs to an ecologically fragile region in North China, which has great impact on the eco-safety of Beijing and Tianjin. Using Landsat TM data and GIS, this paper evaluates land degradation in North Hebei province of China from the the 1960's to 1987 and 2000. Land use/cover change pattern from 1987 to 2000, its regional difference and forest change characteristics will also be analyzed; soil erosion intensity and arable land suitability were also evaluated. Results revealed that land use/cover pattern in this study area did not change greatly from 1987 to 2000. The structure and function of regional land ecosystem was at a level of local improvement and integral deterioration. Land above medium soil erosion intensity reached 21 percent, which was also the area with a serious soil erosion and land degradation problem. Soil erosion and land degradation intensity of grassland was the biggest. For the present arable land, the proportion of high suitability was 13 percent.  相似文献   

18.
基于土地利用变化的四川省生态系统服务价值研究   总被引:11,自引:0,他引:11  
认识和理解土地利用变化对生态系统服务价值的影响及相互作用关系具有重要意义。在分析国内外各种生态服务价值评价方法和对各类生态系统生态服务价值系数进行修正的基础上,采用生态系统服务价值评估模型、敏感性指数和价值变率模型,对各类生态系统的各项生态服务价值、土地利用变化对四川省生态系统服务价值的影响进行了计算和分析。结果表明:(1)四川省土地利用以林地和牧草地为主,1996~2006年耕地、未利用土地、牧草地和水域面积减少,林地、建设用地和园地面积呈增加趋势;(2)1996~2006年四川省生态系统服务价值由1996年的7 214588×108元上升到2006年的7 305018×108元,增加90431×108元,园地生态系统服务价值持续增加,而农田、牧草地、水域、未利用地则继续减少;(3)土地利用的生态服务价值区域差异显著,空间上呈现西多东少的分布格局,西部高山高原区和盆周山区的生态系统服务价值总量较大,成都平原和四川盆地丘陵区所提供的较少;(4)四川省生态系统服务价值缺乏弹性,价值变率反映林地面积的变化对研究区生态系统服务价值的变化具有较大影响  相似文献   

19.
1991-2001年南昌市土地利用/覆被变化特征研究   总被引:11,自引:0,他引:11  
土地利用/覆被变化是区域变化的重要组成部分,是短时期内人类活动对自然环境改造的显著表现形式。南昌市地处京广线和沿海地区之间,属于经济欠发达地区的省会城市。近年来,社会经济发展迅速,城镇化进程明显加快,土地利用变化显著。文章利用1991—2001年南昌市土地详查和变更数据,分析南昌市土地利用/覆被变化特征,其基本结论有: (1)土地利用类型构成以耕地、水域和林地为主;(2)建设用地增幅显著,而耕地数量则呈下降态势,土地利用结构的变化与城镇的发展密切相关;(3)从土地利用程度看,不论是单项指标指数还是综合指数,南昌市均高于全国平均水平;(4)从时间序列看,南昌市土地利用/覆被的多样性指数和均匀度指数逐渐增大,而优势度指数逐渐减小,指数变化的趋势还表现为前一时期(1991—1996年)比后一时期(1996—2001年)要大,这表明土地利用/覆被的破碎化程度持续加强,但后期的加强程度呈弱化趋势。  相似文献   

20.
洞庭湖区土地利用变化对地表产流的影响分析   总被引:7,自引:2,他引:5  
利用20世纪80年代末期和90年代末期获取的陆地资源卫星图像,通过GIS分析方法,对洞庭湖区近10年的土地利用/覆盖变化进行了统计分析。并以1996年7月日降雨资料分别计算了1989年和1999年土地利用状况下区域的产水量。结果表明:洞庭湖区10年间土地利用变化的主要趋势是耕地面积减少和建设用地、水域面积的增加。土地利用的主要转化方式有水田转化为建设用地、水田转化为水域、林地转化为建设用地以及旱地转化为建设用地。同样的降雨条件下,洞庭湖区1999年下垫面状况下的产水量比1989年多206×105 m3,建设用地面积的增加是这一时期产水量增加的主要原因。土地利用的变化影响汛期产水量和汇流速度,加强洪泛区的土地管理,合理控制调整土地利用状况是减轻洪涝灾害威胁的有效手段。  相似文献   

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