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1.
Predicting land cover changes and their impact on the sediment influx in the Lake Balaton catchment 总被引：2，自引：0，他引：2
The land cover pattern in the Lake Balaton catchment (Hungary) has been changing since decollectivization in the 1990s. These
land cover changes significantly impact the landscape connectivity, controlling the influx of sediments into the lake. A comparison
of high resolution land cover maps from 1981, 2000 and 2005 showed a significant extensification of the agriculture with land
cover conversions from arable land and vineyards to grassland and forest. For each land unit transition probabilities were
assessed using logistic regression techniques to evaluate to which extent land cover changes are controlled by physical or
socio-economic parameters. A stochastic land cover allocation algorithm was applied to generate future land cover patterns.
The landscape connectivity for each of the simulated land cover patterns was assessed by means of a distributed routing algorithm.
The simulations suggest that further land abandonment in the upslope parts of the catchment will cause a non-linear reduction
of average soil erosion rates. The changes, however, have a relatively low impact on the sediment volume entering the lake
because of the land unit’s poor connectivity with permanent river channels. The major contributors to the lakes sediment load
are the vineyards near the lakeshore. They are likely to be maintained because of their touristic value. A significant reduction
of the total sediment input in the lake can be expected only if soil conservation measures in the vineyards near the shorelines
are undertaken. 相似文献
2.
Based on re-measurements (1999 and 2001) of randomly-distributed permanent plots within the city boundaries of Baltimore, Maryland, trees are estimated to have an annual mortality rate of 6.6% with an overall annual net change in the number of live trees of –4.2%. Tree mortality rates were significantly different based on tree size, condition, species, and land use. Morus alba, Ailanthus altissima, and trees in small diameter classes, poor condition, or in transportation or commercial – industrial land uses exhibited relatively high mortality rates. Trees in medium- to low-density residential areas exhibited low mortality rates. The high mortality rate for A. altissima is an artifact of this species distribution among land use types (24% were in the transportation land use). Based on a new tree population projection model that incorporates Baltimore's existing tree population and annual mortality estimates, along with estimates of annual tree growth, Baltimore's urban forest is projected to decline in both number of trees and canopy area over the next century. Factors affecting urban tree mortality are discussed. 相似文献
3.
Min Zhao Francisco J. Escobedo Christina Staudhammer 《Urban Forestry & Urban Greening》2010,9(3):205-214
Spatial patterns of tree structure and composition were studied to assess the effects of land tenure, management regimes, and the environment on a coastal, subtropical urban forest. A total of 229 plots in remnant natural areas, private residential, public non-residential, and private non-residential land tenures were analyzed in a 1273 km2 study area encompassing the urbanized portion of Miami-Dade County, USA. Statistical mixed models of structure, composition, location, and land tenure data were used to analyze spatial patterns across the study area. A total of 1200 trees were measured of which 593 trees (49%) were located in residential areas, 67 (6%) in public non-residential areas, 135 trees (11%) in private non-residential areas, and 405 (34%) in remnant, natural areas. A total of 107 different tree species belonging to 90 genera were sampled. Basal area in residential land tenures increased towards the coast while private residential land tenures and natural areas had higher species diversity than non-residential areas. Tree height, crown light exposure, and crown area might indicate the effects of past hurricane impacts on urban forest structure. Land tenure, soil types, and urban morphology influenced composition and structure. Broadleaf evergreen trees are the most common growth form, followed by broadleaf deciduous, palms, and conifers. Exotic tree species originated mainly from Asia and 15% of all trees measured were considered exotic-highly invasive species. We discuss the use of these results as an ecological basis for management and resilience towards hurricane damage and identifying occurrence of invasive, exotic trees. 相似文献
4.
Trees on leased land provide an important contribution to Canberra's urban forest and consequently the Australian Capital Territory (ACT) Government introduced legislation to protect urban trees on leased land from unwarranted removal under the Tree Protection (Interim Scheme) Act 2001. This tree protection legislation applies to significant trees, classified using size-based criteria, on leased land for urban and other non-rural purposes. Responsibility resides with the ACT Government to preserve and protect significant trees on leased land in Canberra, until such time as removal is warranted and prudent. On Saturday 18 January 2003, 2 years after the introduction of the tree protection legislation, Canberra experienced a state of emergency when major bushfires swept through the bush–urban interface and penetrated into the western urban area subsequently destroying or damaging over 500 houses. There was a substantial increase in requests lodged under the Act immediately after the fires, but by February 2004 the number of requests returned to February 2002 levels which suggests leaseholder response to the fire declines relatively quickly. The percentage of requests approved (88%) remained relatively constant which indicates that the increased number of applications were for reasons that were considered valid under the Act although it is unlikely that these concerns only became valid during the month proceeding the fire. Dominant genera removed each February from 2002 to 2004 were similar; however, Eucalyptus species have shown a small but significant relative increase although there are insufficient data to conclude this increase indicates an increased aversion to this genus. Future management needs to consider the community perception of trees and temporal reaction to major events. 相似文献
5.
The riparian forests along braided rivers are dynamic, frequently rejuvenated by floods and channel changes, and thus dominated
by pioneer to middle stages of succession; they are sites of high biodiversity in some regions. The Lower Eygues River (drainage
area 1150 km2 in southeastern France) is such a braided river system with large alluvial forests dominated by Salix alba, Populus alba, and P. nigra. It was identified as a site of ecological interest by the EU under the Natura 2000 program. Such forests elsewhere in Europe have been identified as reference ecosystems. We documented the historical evolution
of this alluvial forest from detailed (1:2500 scale) early 19th C parcel maps, early 20th C topographic maps, aerial photography
from 1947 to 1996, and field surveys of topography and riparian vegetation in 1997–1998. Our results show that in 1830, the
channel was wide, aggraded, and agricultural pressure extended literally to the channel edge. With decline in the rural population
and reduced agricultural and grazing pressure in the catchment, erosion rates declined. Reduced sediment supply led to channel
narrowing and incision. This channel narrowing, coupled with reduced agricultural pressure along the banks, has allowed riparian
forest to colonize former active channel areas, especially within late 19th-century 20th century flood dykes. In recent decades,
aggregate mining, and clearing for recreation and agriculture have fragmented the forest. Thus, the alluvial forest of the
Lower Eygues is largely an artifact of changing human land-use over the past century, a context that should frame efforts
for preservation and restoration. 相似文献
6.
Land-use changes and sustainable development in mountain areas: a case study in the Spanish Pyrenees
José M. García-Ruiz Teodora Lasanta Purificación Ruiz-Flano Luis Ortigosa Sue White Constanza González Carlos Martí 《Landscape Ecology》1996,11(5):267-277
Land-use changes affecting Mediterranean mountains represent the intensification of use in valley bottoms, accompanied by land-use conflicts, and a generalized abandonment of the hillslopes, which in the past were perfectly integrated in the system of land management. Farmland abandonment, reforestation, diminution of the livestock pressure and substitution of cereal crops by meadows are the most outstanding features of the recent land-use changes. The question is whether the new spatial organisation is in accordance with a longterm policy of sustainable development in mountain areas. The results obtained confirm that farmland abandonment on steep slopes — and the resulting colonization of old fields by a dense shrub cover — and afforestation contribute to control both soil erosion and surface runoff. As a result some of the most important rivers and alluvial fans have recently stabilized their sedimentary structures. 相似文献
7.
Land-use and vegetation cover have been linked to the nutrient levels (nitrogen, phosphorus) of surface waters in several
countries. However, the links generally relate to streams and rivers, or to specific types of standing water, for example
shallow lakes in a geologically defined region. We measured physical variables and nutrient chemistry of 45 water bodies representative
of the wide range of lentic wetland environments (swamps, riverine wetlands, estuaries, reservoirs, shallow lakes, deep lakes)
in Otago, New Zealand, and related these to catchment variables and land-use in order to assess the potential influence of
catchment modification on water quality of these diverse wetlands. Catchment boundaries and land cover were derived from maps
using ArcView GIS software. Our predictions that concentrations of nutrients and other components of water quality would correlate
positively with the nature and intensity of catchment modification were confirmed in multivariate analyses. Physical and chemical
measures were positively related to the extent of modification in the catchment (percentage of the catchment in pasture, planted
forest, scrub and urban areas), and negatively related to lack of catchment modification (more of the catchment in bare ground,
tussock grassland and indigenous forest). The strong negative correlations between nutrient concentrations, suspended sediment,
water colour and the percentage of tussock cover in the catchment imply that increased conversion of the␣native tussock grassland
to pastoral farming in␣Otago will increase nutrient concentrations and␣reduce water quality of the diverse lentic ecosystems. 相似文献
8.
Since the mid eighties, agricultural development and increased population growth in Vietnam’s northern highlands have modified
land use patterns and thus, increased the runoff process and soil degradation induced by water erosion. In the last decade,
Vietnamese literature has focused on the computation of soil losses over large areas. Most of these spatial and quantitative
soil erosion studies do not consider the impact of agricultural land use diversity (spatial heterogeneity), particularly at
the watershed scale, and the annual variability of seasonal landscape factors on soil erosion vulnerability and hence, landscape
dynamics. We present an integrated approach combining field measurements and observations, GIS and modeling to determine the
spatial and temporal dynamics of soil erosion vulnerability according to watershed units and hence, the impact of physical
environment components and agricultural land use patterns on landscape evolution. Tables and graphics showing the cropping
systems, the periods within a year, and the watershed units that are most vulnerable are presented. The double cultivation
cycles for paddy rice fields not only imply two periods of land preparation and establishment that expose the soil surface
to raindrop impacts, but also increased soil management practices that decrease the soil’s resistance to detachment. Despite
the low levels of soil management practices for the shifting cultivation system, the near absence of soil conservation practices
clearly increases their vulnerability. Hence, rainfed cropping systems, mainly soya and cassava, cultivated on sloping lands
(hills and mountains) where soil erosion vulnerability is the highest represent the watershed units which are the most prone
to soil loss. 相似文献
9.
Wayne C. Zipperer 《Landscape Ecology》1993,8(3):177-184
Five identifiable patterns of deforestation are recognized - internal, indentation, cropping, fragmentation, and removal - and each has a distinct effect on habitat quality of forest patches in the eastern United States. By overlaying land use maps from 1973 and 1981 for three counties in the State of Maryland (Prince Georges, Anne Arundel, and Wicomico), changes in the interior core area and edge length of individual patches were measured. Forest interior declined by 23.8 km2 in Anne Arundel, 16.3 km2 in Prince Georges, and 8.4 km2 in Wicomico. Within Anne Arundel and Prince Georges Counties, deforestation increased edge length by 52.1 km and 31.2 km, respectively, whereas, within Wicomico, it decreased edge length by 8.7 km. Differences among counties resulted from current land use patterns, percentage of forest cover, and the dominant deforestation pattern. 相似文献
10.
The resilience of Christchurch, New Zealand's urban forest has been tested during a year of major earthquakes and aftershocks. Tree loss has resulted from mass soil movement, soil liquefaction, rockfalls, and land slips. At the time of writing, only 384 trees have been documented as removed, however, thousands more are scheduled for removal. Additionally, the changes to the soil environment resulting from liquefaction will require existing trees to adapt quickly to their new soil environment. Their fate will not be known for years. Though the total number of trees removed is unlikely to reduce city-wide canopy cover appreciably, it is important to recognize that spatial patterns of tree loss were highly localized and thus local canopy cover has been drastically reduced in some areas. Short-term management of the urban forest in the aftermath of the earthquake focused on removal of trees deemed unstable or unsafe. In the medium-term, attempts have been made to monitor the health and stability of remaining trees using an asset management system, though some difficulties related to consistency and ubiquity of its use have been identified. Though short and medium-term management have been largely effective, long-term management of Christchurch's urban forests will largely be dictated by government policy, which will be informed by public consultation and land ownership. Many of the benefits provided by urban forests are well understood. However, trees and greenspaces provided additional benefits during earthquakes and in the aftermath. Planted trees in the hills surrounding the city prevented rockfall from damaging infrastructure and human life downslope, while greenspaces were used as a base for search and rescue staff during rescue and recovery operations, and as temporary living spaces for residents who lost their homes. 相似文献
11.
The planning and management of urban forest has become increasingly important as a focus of urban environmental management. The objectives of this study were to analyze the landuse/land cover and to map functional zones of the urban forest in the upper catchment area of Addis Ababa. This study identifies five landuse/land cover types: (i) Eucalyptus–Juniperus dominated forest, (ii) mixed native forest, (iii) built-up areas, (iv) Eucalyptus plantation (v) crop/grazing lands. The vegetation analysis shows 44 woody plant species representing 31 families, out of which 13 tree species, 29 shrubs and two species of lianas. The woody species diversity was 1.35 with the species richness and evenness of 44 and 0.80, respectively. This indicates that the forest has poor species diversity which is attributed to high anthropogenic pressure and monoculture plantation development strategies in the last decades. The density of plants ranged from 25 for Olea europea to 825 individuals per hectare for Eucalyptus globules from the tree layers and from 50 for Dombeya torrida and Erica arborea to 900 individuals per hectare for Myrsine africana from shrub layers. Based on importance value index (IVI), Eucalyptus globulus and Juniperus procera showed the highest IVI of 96.37 and 54.80, respectively as compared to other species. The forest structure showed higher contagious distribution where out of the recorded 44 species, 37 species showed contagious distribution. The result also showed poor regeneration potential in all studied forest layers. Based on the landuse/cover analysis, the phytosociological study and field observation, this study recommends six urban forest zoning. These include: (i) conservation zone, (ii) recreation zone, (iii) production zone, (iv) agroforestry zone, (v) reforestation zone, (vi) buffer zone between the green area and the built-up environment. The green area in the upper catchment has no definite boundaries and needs re-demarcation activities. 相似文献
12.
Eben N. Broadbent Angélica M. Almeyda Zambrano Rodolfo Dirzo William H. Durham Laura Driscoll Patrick Gallagher Rosalyn Salters Jared Schultz Angélica Colmenares Shannon G. Randolph 《Landscape Ecology》2012,27(5):731-744
Development in biodiversity rich areas is of global concern. While development may lead to socioeconomic benefits, this often
comes concomitant with biodiversity loss and deforestation. Biodiversity rich areas present the opportunity for both improvements
in socioeconomic conditions and conservation; however numerous challenges exist. Costa Rica’s Manuel Antonio National Park
presents an ideal case study to investigate the balance between alternative forms of development which have contrasting environmental
impacts. The Manuel Antonio region is a highly dynamic landscape experiencing deforestation, from agriculture, cattle ranching
and oil palm plantations; and also reforestation from abandonment of land holdings and nature oriented tourism. Landscape
dynamics are closely intertwined with the livelihoods and perspectives on biodiversity conservation of local communities,
determining ecological sustainability. We use an analysis combining multi-temporal remote sensing of land cover dynamics from
1985 to 2008 with questionnaire data from local families on their socioeconomic status, perspectives on conservation, and
perceived changes in local wildlife populations. Our results show that, while regeneration occurred and forest fragmentation
in the area decreased from 1985 to 2008, Manuel Antonio National Park is rapidly becoming isolated. Decreasing ecological
connectivity is related to the rapid expansion of oil palm plantations adjacent to the park and throughout the lowland areas.
Perceived decreases in wildlife abundance and compositional change are evident throughout the area, with local communities
attributing this primarily to illegal hunting activities. Nature based tourism in the area presents an effective strategy
for conservation, including reductions in hunting, through increased valuation of biodiversity and protected areas, and socioeconomic
advantages. However, without urgent efforts to limit deforestation and preserve the remaining forested corridor connecting
the park to core primary forest, the ability to maintain biodiversity in the park will be reduced. 相似文献
13.
Due largely to unprecedented land-use changes in the Porijõgi River catchment (southern Estonia) losses of nutrients and organic matter have decreased significantly. During the period 1987–1997 abandoned lands increased from 1.7 to 10.5% and arable lands decreased from 41.8 to 23.9%. At the same time, the runoff of total-N, total-P, SO4 and organic matter (after BOD5) decreased from 25.9 to 5.1, 0.32 to 0.13, 78 to 48, and 7.4 to 3.5 kg ha–1 yr–1, respectively. The most significant decreases occurred in agricultural subcatchments while the changes were insignificant in the forested upper course catchment. A simple empirical model which incorporates land-use pattern, fertilization intensity, soil parameters and water discharge accurately described the variations of total-N and total-P runoff in both the whole catchment and its agricultural subcatchments (R
2 varies from 0.95–0.99 for N to 0.49–0.93 for P). In small agricultural subcatchments the rate of fertilization is found the most important factor for nitrogen runoff, whereas in larger mosaic watersheds land use pattern plays the main role. Seven alternative scenarios compiled on the base of the empirical model allow to forecast potential nitrogen and phosphorus losses from the catchment. This information can be used in further landscape and regional planning of the whole region. 相似文献
14.
Small-scale effects of historical land use and topography on post-cultural tree species composition in an Alpine valley in southern Switzerland 总被引：1，自引：0，他引：1
Investigations of spatial patterns in forest tree species composition are essential in the understanding of landscape dynamics,
especially in areas of land-use change. The specific environmental factors controlling the present patterns, however, vary
with the scale of observation. In this study we estimated abundance of adult trees and tree regeneration in a Southern Alpine
valley in Ticino, Switzerland. We hypothesized that, at the present scale, spatial pattern of post-cultural tree species does
not primarily depend on topographic features but responds instead to small-scale variation in historical land use. We used
multivariate regression trees to relate species abundances to environmental variables. Species matrices were comprised of
single tree species abundance as well as species groups. Groups were formed according to common ecological species requirements
with respect to shade tolerance, soil moisture and soil nutrients. Though species variance could only be partially explained,
a clear ranking in the relative importance of environmental variables emerged. Tree basal area of formerly cultivated Castanea sativa (Mill.) was the most important factor accounting for up to 50% of species’ variation. Influence of topographic attributes
was minor, restricted to profile curvature, and partly contradictory in response. Our results suggest the importance of biotic
factors and soil properties for small-scale variation in tree species composition and need for further investigations in the
study area on the ecological requirements of tree species in the early growing stage. 相似文献
15.
16.
Tropical deforestation is a major contributor to green house gas emissions in developing countries. Incentive mechanisms,
such as reducing emissions from deforestation and forest degradation (REDD), are currently being considered as a possible
emissions reduction and offset solution. Although REDD has expanded its scope to include co-benefits such as sustainable management
of forests and biodiversity conservation (known as REDD+), current carbon-base methodologies do not specifically target projects
for the parallel protection of these co-benefits. This study demonstrates the incorporation of both carbon and biodiversity
benefits within REDD+ in the Bolivian Amazon, through the analysis of land cover change and future change scenario modeling
to the year 2050. Current protected areas within the Bolivian Amazon were evaluated for REDD+ project potential by identifying
concordant patterns of carbon content, species biodiversity and deforestation vulnerability. Biodiversity-based versus carbon-based
protection schemes were evaluated and protected areas were prioritized using irreplaceability-vulnerability plots. Deforestation
projection scenarios to the year 2050 varied depending on the historical period analyzed, producing low, intermediate and
high deforestation scenarios. All scenarios showed increasing deforestation pressure in the northern region of Bolivia along
with high levels of biodiversity loss. Expected reductions in the carbon pool ranged from 8 to 48%, for the low and high demand
scenarios respectively. Some protected areas presented large numbers of endemic species, high concentrations of carbon and
high deforestation vulnerability, demonstrating the potential for win–win REDD+ projects in Bolivia. 相似文献
17.
Forest fragmentation and regrowth in an institutional mosaic of community, government and private ownership in Nepal 总被引：1，自引：0，他引：1
Harini Nagendra Sajid Pareeth Bhawna Sharma Charles M. Schweik Keshav R. Adhikari 《Landscape Ecology》2008,23(1):41-54
This study analyzes forest change in an area of Nepal that signifies a delicate balance between sustaining the needs and livelihood
of a sizable human population dependent on forest products, and an effort to protect important wildlife and other natural
resources. The study area, a portion of the Chitwan valley district of Nepal, represents what may be becoming a common institutional
mosaic in many countries of the world who have a population reliant on forest products for their livelihood: (1) a national
park; (2) a designated park buffer involving participatory forest management programs; (3) scattered patches of designated
community forest; and (4) large areas of adjacent landscape made up of mostly private landholdings under agricultural practices.
Utilizing Landsat images from 1989 and 2000, we analyze land cover change in each of these management zones using landscape
ecology metrics and quantifying proportional distributions of land cover categories. Our results show significant differences
in terms of land cover dynamics and landscape spatial pattern between these land ownership classes. These findings indicate
that community-based institutions (participatory management programs in the park buffer and the designated community forests)
are capable of halting or even reversing trends in deforestation and forest fragmentation. 相似文献
18.
Human-induced land cover changes are causing important effects on the ecological services rendered by mountain ecosystems, and the number of case-studies of the impact of humans on soil erosion and sediment yield has mounted rapidly. In this paper, we present a conceptual model that allows evaluating overall changes in erosion regulation after human disturbances. The basic idea behind this model is that soil erosion mechanisms are independent of human impact, but that the frequency–magnitude distributions of erosion rates change as a response to human disturbances. Pre-disturbance (or natural) erosion rates are derived from in situ produced 10Be concentrations in river sediment, while post-disturbance (or modern) erosion rates are derived from sedimentation rates in small catchments. In its simplicity, the model uses vegetation cover change as a proxy of human disturbance. The erosion regulation model is here applied in two mountainous regions with different vegetation dynamics, climatic and geological settings: the Austro Ecuatoriano, and the Spanish Betic Cordillera. Natural erosion benchmarks are necessary to assess human-induced changes in erosion rates. While the Spanish Betic Cordillera is commonly characterized as a degraded landscape, there is no significant difference between modern catchment-wide erosion and long-term denudation rates. The opposite is true for the Austro Ecuatoriano where the share of natural erosion in the total modern erosion rate is minimal for most disturbed sites. When pooling pre- and post-disturbance erosion data from both regions, the data suggest that the human acceleration of erosion is related to vegetation disturbances. The empirical regression model predicts human acceleration of erosion, here defined as the ratio of post-disturbance to pre-disturbance (or natural benchmark) erosion rate, as an exponential function of vegetation disturbance. This suggests that the sensitivity to human-accelerated erosion would be ecosystem dependent, and related to the potential vegetation cover disturbances as a result of human impact. It may therefore be expected that the potential for erosion regulation is larger in well-vegetated ecosystem where strong differences may exist in vegetation cover between human disturbed and undisturbed or restored sites. 相似文献
19.
由于人类对土地功能的认识单一,造成乡村地区土地利用不充分,导致土地资源的闲置与浪费。而土地单一功能利用模式转变的关键是探究土地多功能的利用。以北流河流域林地为研究区对象,从气候、土壤、地质、地形、植被要素进行综合分析,对林地土地的生产功能、生态功能、景观功能和材料功能进行空间定量化,运用热点分析和地理探测器评价北流河流域林地多功能性及影响因素;并通过K均值聚类分析划分林地土地多功能利用类型区。结果表明：(1)流域内林地多功能热点区域呈集聚分布,冷点区域呈带状分布在北流河流域的山麓。(2)北流河流域林地多功能空间分异的驱动力主要以植被因素为主,其中郁闭度、蓄积量、碳汇为主导因子,植被盖度对林地土地多功能空间分异的影响较小,应加强北流河流域内的植被保护和严禁过度开发林地;交互作用明显,交互作用均为双因子增强或非线性增强,气候、土壤、植被、地形、地质条件共同制约着北流河流域林地多功能水平。(3)通过伪F统计将北流河流域林地划分为3个主导区和1个提升区,分别为生产功能主导区、生态功能主导区、景观功能主导区以及综合功能提升区,其中生态功能主导区面积最大;并针对主导功能提出相应的利用方向。 相似文献
20.
Accessibility as a determinant of landscape transformation in western Honduras: linking pattern and process 总被引：11，自引：2，他引：11
This study evaluates the relationship between landscape accessibility and land cover change in Western Honduras, and demonstrates
how these relationships are influenced by social and economic processes of land use change in the region. The study area presents
a complex mosaic of land cover change processes that involve approximately equal amounts of reforestation and deforestation.
Landsat Thematic Mapper (TM) satellite imagery of 1987, 1991 and 1996 was used to create three single date classifications
and a land cover change image depicting the sequence of changes in land cover between 1987–1991–1996. An accessibility analysis
examined land cover change and landscape fragmentation relative to elevation and distance from roads. Between 1987 and 1991,
results follow ‘expected’ trends, with more accessible areas experiencing greater deforestation and fragmentation. Between
1991 and 1996 this trend reverses. Increased deforestation is found in areas distant from roads, and at higher elevations;
a result of government policies promoting expansion of mountain coffee production for export. A ban on logging, and abandonment
of marginally productive agricultural fields due to agricultural intensification in other parts of the landscape, has led
to increased regrowth in accessible regions of the landscape. Roads and elevation also present different obstacles in terms
of their accessibility, with the smallest patches of cyclical clearing and regrowth, relating mostly to the agricultural fallow
cycle, found at the highest elevations but located close to roads. This research highlights the need to locate analyses of
land cover change within the context of local socio-economic policies and land use processes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献