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1.
There has been a concerted effort by the international scientific community to understand the multiple causes and patterns of land-cover change to support sustainable land management. Here, we examined biophysical suitability, and a novel integrated index of “Economic Pressure on Land” (EPL) to explain land cover in the year 2000, and estimated the likelihood of future land-cover change through 2050, including protected area effectiveness. Biophysical suitability and EPL explained almost half of the global pattern of land cover (R 2 = 0.45), increasing to almost two-thirds in areas where a long-term equilibrium is likely to have been reached (e.g. R 2 = 0.64 in Europe). We identify a high likelihood of future land-cover change in vast areas with relatively lower current and past deforestation (e.g. the Congo Basin). Further, we simulated emissions arising from a “business as usual” and two reducing emissions from deforestation and forest degradation (REDD) scenarios by incorporating data on biomass carbon. As our model incorporates all biome types, it highlights a crucial aspect of the ongoing REDD + debate: if restricted to forests, “cross-biome leakage” would severely reduce REDD + effectiveness for climate change mitigation. If forests were protected from deforestation yet without measures to tackle the drivers of land-cover change, REDD + would only reduce 30 % of total emissions from land-cover change. Fifty-five percent of emissions reductions from forests would be compensated by increased emissions in other biomes. These results suggest that, although REDD + remains a very promising mitigation tool, implementation of complementary measures to reduce land demand is necessary to prevent this leakage.  相似文献   

2.
Land-use change is one of the major factors that alter local and regional hydrology. For areas experiencing fast expansion of urban and agriculture areas, land-use changes often adversely affect stream flow and water resources at the local and watershed scale. The Sekong, Sesan, and Srepok (3S) Sub-basins are a part of the Lower Mekong River Basin and include land in Cambodia, Lao People’s Democratic Republic (Laos), and Viet Nam. The region is experiencing a dynamic land-use transition because of rapid changes in its economy, society, and environment. Major land-use changes include deforestation of native rain forest, expansion of agricultural and urban areas, and expansion of commercial plantation such as rubber trees. These land-use alterations have affected local and regional hydrologic processes, resulting in stream flow shortages during the dry season and flash flooding due to deforestation. In this research, deforestation in the 3S Sub-basins over the period 1993–1997 was analyzed using multi-logistic regression. The regression analysis indicated that density of agricultural cells within a 5-km radius from each forest cell and slope strongly affected the deforestation process. A land-use forecast model to simulate deforestation and urbanization sites was developed in GIS based on local land-use change trends. The model was applied to 2003 land use to forecast 2033 land use and future water demand, which was further compared with present stream flow measurements during the dry season at various places in the region. The entire approach from the land-use forecast to its impact assessment on stream flow could help local stakeholders understand watershed-wide future water resources risks and develop future water resources plans. With the 3S Sub-basins being used as a case study area, this article presents a land-use forecast tool; simulated 2033 land-use and water demand; and the estimation of the impact of the forecasted future water demand on the local stream flow.  相似文献   

3.
Fuelwood is one of the major sources of energy in the domestic sector across the rural areas, especially in the developing regions across the world. The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area. The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region, thus indicating the livelihood conditions. Since land-use land-cover change is the key driver to the change in resource availability of a region, the present study has tried to analyze the land-cover changes over a period 28 years. The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics, which directly affect the resource production. Based on the existing consumption pattern, the total consumption of fuelwood in the watershed ranges from a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year. Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.  相似文献   

4.
District Swat is part of the high mountain Hindu-Kush Himalayan region of Pakistan. Documentation and analysis of land use change in this region is challenging due to very disparate accounts of the state of forest resources and limited accessible data. Such analysis is, however, important due to concerns over the degradation of forest land leading to deterioration of the protection of water catchments and exposure of highly erodible soils. Furthermore, the area is identified as hotspot for biodiversity loss. The aim of this paper is to identify geophysical and geographical factors related to land use change and model how these relationships vary across the district. For three selected zones across the elevation gradient of the district, we analyse land use change by studying land use maps for the years 1968, 1990 and 2007. In the high-altitude zone, the forest area decreased by 30.5 %, a third of which was caused by agricultural expansion. In the mid-elevation zone, agriculture expanded by 70.3 % and forests decreased by 49.7 %. In the lower altitudes, agriculture expansion was 129.9 % consuming 31.7 % of the forest area over the forty-year time period. Annual deforestation rates observed were 0.80, 1.28 and 1.86 % in high, mid and low altitudes, respectively. In the high-altitude ecosystems, accessibility (distance to nearest road and city) had no significant role in agriculture expansion; rather land use change appears significantly related to geophysical factors such as slope, aspect and altitude. In the low-elevation zone, accessibility was the factor showing the closest association with agriculture expansion and abandonment. The analysis illustrates that land use change processes vary quite considerably between different altitudinal and vegetation cover zones of the same district and that environmental constraints and stage of economic development provide important contextual information.  相似文献   

5.
High deforestation rates in tropical countries continue to reduce forest cover and thereby habitat quantity and quality. However, in some places the forest is recovering and expanding thus offsetting the biodiversity and ecosystem service losses. In order to characterize the forest recovery, land use and land cover (LUC) changes were analyzed using aerial photographs, taken between 1952 and 2009, of a peri-urban watershed in the Andes region of Venezuela. The qualities of the changes were assessed using landscape indices and hemeroby indicators. In that period, the forest cover increased about 18 %, mainly due to abandoned pastures on steep slopes. At the same time, the urban area expanded about 4 % on valley bottoms, while pastures and crop fields were reduced about 20 %. The results also showed that forest patches were aggregating, whereas pastures were fragmenting. A reduction in direct human impacts on forests growing on abandoned pastures resulted in a slight recovery of the lower montane cloud forest structure and plant composition. But non-native species were found in all LUC categories. During the study period, we documented not only forest recovery, but also urban area growth, intensified land use and invasions by non-native species all of which could partially counterbalance the positives of forest recovery.  相似文献   

6.
Extensive forests in Croatia represent an important biological and economic resource in Europe. They are characterised by heterogeneity in forest management practices dating back to the socialist planned economy of the pre-1991 era. In this study we investigated the difference in rates of deforestation and reforestation in private- and state-owned forests during the post-socialist period and the causal drivers of change. The selected region of Northern Croatia is characterised by a high percentage of privately owned forests with minimal national monitoring and control. We used a mixed-methods approach which combines remote sensing, statistical modelling and a household-based questionnaire survey to assess the rates of forest cover change and factors influencing those changes. The results show that predominantly privately owned forests in Northern Croatia have recorded a net forest loss of 1.8 % during the 1991–2011 period, while Croatia overall is characterised by a 10 % forest cover increase in predominantly state-owned forests. Main factors influencing forest cover changes in private forests are slope, altitude, education structure, population age and population density. The results also show that the deforestation in private forests is weakening overall, mostly due to the continuation of the de-agrarisation and de-ruralisation processes which began during socialism.  相似文献   

7.
8.
There has been a significant lack of land cover change studies in relation to deforestation in the Democratic People’s Republic of Korea (North Korea). The purpose of this study is to characterize deforestation in North Korea through land cover change trajectory and spatial analysis. We used three 30-m gridded land cover data sets for North Korea representing the conditions of the late 1980s, 1990s, and 2000s, respectively, as well as a digital elevation model. We examined the land cover trajectories during the two decades, i.e., which land cover became which at the pixel level. In addition, we calculated topographic characteristics of deforested pixels. Major findings from the study are summarized as follows: (1) net forest loss in North Korea was negligible in the latter decade compared to the former (>5000 km2), whereas other land cover changes were still active; (2) as a result of deforestation, forest land cover became mostly agricultural, particularly in the latter decade (95 %); (3) expansion of agricultural land cover continued during the time, increasing by >42 %; and (4) elevation and slope of deforested areas decreased slightly in the latter decade. The key contribution of the study is that it has demonstrated which land cover became which at the 30-m pixel level, complementing existing studies that examined overall forest stock in North Korea.  相似文献   

9.
Identifying the patterns of land cover change (LCC) and their main proximate causes and underlying driving forces in tropical rainforests is an urgent task for designing adequate management and conservation policies. The Lachuá region maintains the largest lowland rainforest remnant in Guatemala, but it has been highly deforested and fragmented during the last decades. This is the first paper to describe the patterns of LCC and the associated political and socioeconomic factors in the region over the last 50 years. We estimated spatial and temporal variations in LCC from a random sample of 24 1-km2 landscape plots during three time periods (1962–1987, 1987–2006, and 2006–2011) and evaluated how they were related to some important proximate causes and underlying driving forces. During the study period, 55 % of forest cover disappeared, at an annual rate of 1.6 %. The deforestation rate increased from 0.6 % (during the first study period) to 2.8 % (last period), but there was very high spatial variation. Landscape plots located outside conservation areas and close to roads lost between 80 and 100 % of forest cover, whereas the forest cover in landscapes located within protected areas remained intact during the study period. The establishment of new human settlements, roads, and annual crops was the main proximate cause during the first period, but during the second and third periods, open areas were mainly created to establish cattle pastures. Because ~75 % of forest cover has disappeared outside the protected areas, the conservation of this biodiversity hot spot will depend on the expansion of protected areas, and the promotion of forest regrowth and alternative biodiversity-friendly land uses in the landscape matrix.  相似文献   

10.
The conservation of forests in expanding frontier landscapes is critically important to maintain intact forest ecosystems and support forest dependent communities. To conserve frontier forests, policy approaches are needed that conserve forests and advance the well-being of local resource dependent communities. To identify such approaches, the forest conservation and development framework (FCDF) was designed to find place-based conservation-development policies that target system leverage-points influencing land-use practices. To demonstrate the utility of the FCDF, a portfolio of conservation-development policies were identified for Peru’s Manu-Tambopata Corridor (MAT) and evaluated by local land-users. Results of the MAT case study show high levels of interest in the proposed policies, but a wide variation in interest levels relative to personal circumstances and policies proposed. Barriers to implementing conservation-development policies in frontier environments were also identified, including high value land-use alternatives generating high opportunity costs for accepting PES payments (e.g., REDD+), insecure land tenure and conflicting authorizations limiting land-users policy choices, and broad demographic diversity among local land-users. Collectively, this research suggests the FCDF is a useful approach for identifying policies matched to local conditions that advance conservation and human development. This research also indicates policy design in frontier environments is most effective when adapted to local conditions, seeks to identify a mix of complementary policies, and is targeted at key system variables influencing land-use practices (i.e., system leverage-points). Importantly, the MAT case study also highlights how even in rapidly changing frontier landscapes, land-users are interested in policies that advance conservation and development goals.  相似文献   

11.
The Alemaya district (Eastern Ethiopian highlands) is characterized by undulating physiographic features with arid, semi-arid, and humid climatic conditions. This study evaluated socio-environmental changes in land use and land cover during 1985–2011. Screen digitization on remotely sensed data (i.e., Landsat images from 1985 to 2011) was performed to produce 10 classes of land use and land cover. Then, final land-use maps were prepared using a geographic information system following field verification and accuracy assessment. The drying of water bodies, including the prominent lakes Alemaya, Adele, and Tinike, had been the most important environmental change observed. Degraded land, marsh, perennial cropland, and residential areas increased by 37, 438, 42, and 190 %, respectively, whereas grassland, plantation, shrubland, and temporal cropland decreased by 64, 11, 63, and 29 %, respectively. The increase in land degradation (+37 %), the other major observed problem, has made large areas unsuitable for agriculture and has reduced crop productivity. These land-use and land-cover changes have affected both the environment and the livelihoods of local residents; especially the issue related to land degradation requires urgent attention.  相似文献   

12.
The current state of Mediterranean mountain areas has been driven by two main factors: intense traditional human activity and the dynamics of the ecosystem itself. In this study, we examine land-cover changes in a National Park in the Pyrenees mountains (NE Iberian Peninsula), which was designated a protected area 55 years ago. First, we have analyzed spatio-temporal changes in land-cover pattern and forest dynamics from 1957 to 2005. During this period, land-cover dynamics consisted of two main processes: (i) expansion of the forest area and (ii) increasing cover of forests already present in 1957. To analyze the role of the conservation level of the park, we have also compared the results obtained within the park with those of unprotected, peripheral areas. In the two areas with different protection level, dense forests increased throughout the period because of the reduction in forestry activities. The peripheral area showed a higher rate of forest-cover change from 1957 to 2005 compared to the National Park. This higher increase in forest cover in the peripheral area could be related to a higher proportion in the National Park of screes and rocky areas and to the decline and transformation of forest activities in these peripheral, lower elevation areas.  相似文献   

13.
The present study used temporal remote sensing data for 1990, 2001 and 2006 to assess spatio-temporal patterns of forest cover changes in Shiwalik range of the Himalaya, Dehradun forest division. Forests are innately associated to human well-being. However, with the increasing anthropogenic activities, deforestation has increased. Quantitative change analysis of the forest cover for the past two decades provides valuable insight into the forest conservation vis-à-vis anthropogenic activities in the region. Spatio-temporal datasets along with biotic and abiotic variables provide opportunities to model the forest cover change further. The present study investigates forest cover change and predicts status of forest cover in the Dehradun forest division. Land Change Modeller (LCM) was used to predict status of forest cover for 2010 and 2015 using current disturbance scenarios. Comparing actual LULC of 2006 with the predicted LULC of 2006 validated change prediction model and agreement was 61.03%. The forested areas are getting degraded due to anthropogenic activities, but deforestation/degradation does not contribute much in expanding urban area. Agricultural areas and fallow lands are the main contributors to increased urban area. The study demonstrates the potential of geospatial tools to understand spatio-temporal forest cover change and generate the future scenarios.  相似文献   

14.
Forests in lowland Bolivia suffer from severe deforestation caused by different types of agents and land use activities. We identify three major proximate causes of deforestation. The largest share of deforestation is attributable to the expansion of mechanized agriculture, followed by cattle ranching and small-scale agriculture. We utilize a spatially explicit multinomial logit model to analyze the determinants of each of these proximate causes of deforestation between 1992 and 2004. We substantiate the quantitative insights with a qualitative analysis of historical processes that have shaped land use patterns in the Bolivian lowlands to date. Our results suggest that the expansion of mechanized agriculture occurs mainly in response to good access to export markets, fertile soil, and intermediate rainfall conditions. Increases in small-scale agriculture are mainly associated with a humid climate, fertile soil, and proximity to local markets. Forest conversion into pastures for cattle ranching occurs mostly irrespective of environmental determinants and can mainly be explained by access to local markets. Land use restrictions, such as protected areas, seem to prevent the expansion of mechanized agriculture but have little impact on the expansion of small-scale agriculture and cattle ranching. The analysis of future deforestation trends reveals possible hotspots of future expansion for each proximate cause and specifically highlights the possible opening of new frontiers for deforestation due to mechanized agriculture. Whereas the quantitative analysis effectively elucidates the spatial patterns of recent agricultural expansion, the interpretation of long-term historic drivers reveals that the timing and quantity of forest conversion are often triggered by political interventions and historical legacies.  相似文献   

15.
In recent years, Amazonian deforestation has become a question of global concern. Deforestation in Amazon is a complex phenomenon in nature and has been related to traditional agriculture expansion. In this work, land use, socioeconomic and conservation indicators, combined with statistical analysis, were used to understand forces associated with patterns of deforestation. This approach was applied in Southern Brazilian Pre-Amazon in Mato Grosso State, which represents an extensive rain forest-savanna ecotone, located in the south border of Amazon biome. Based on data from the last two agricultural censuses (1995/1996–2006), we compared agricultural expansion in this area and Mato Grosso state. Results have shown that 85 % of state deforestation was concentrated in Southern Pre-Amazon and was closely related to increase in number of cattle and pasture area. PCA results pointed that population (92 %), number of cattle (86.5 %), pastures (84.2 %) and tractors (78.4 %) were variables with highest positive correlation to deforestation. It showed that GDP contributes to an individual axis and has a low correlation to deforestation (37.8 %). Conservation units and indigenous reserves also contribute to a single axis and were negatively correlated to temporary crops area. Results revealed a significant reduction in production and commercialization of extractive products in the region, revealing that the main, almost only conservation policy in Mato Grosso remains the creation of Special Areas. We suggest that further studies are necessary to screen development alternatives to simple cutting trees down. It is important to diversify strategies for deforestation control, and development aspects must be more seriously considered to reach a sustainable deforestation control policy.  相似文献   

16.
Colombian Andean forests cover nine million ha. These forests provide an informative case study of mountain deforestation in South America. They are surrounded by tropical lowland forests, and they host most of the country’s human population. This study evaluates the relative importance of human and natural variables in deforestation of the Colombian Andes between 1985 and 2005 using remote sensing methods, geographic information system (GIS) technology and general linear models (GLM). The following factors affected the annual deforestation in the region positively: forced population migration, unsatisfied basic needs, economic activity, crops, pastures, illicit crops, protected areas and slope. Factors having a negative effect were tenure of small land parcels, road density, water scarcity and mean temperature. The results of this study also provide insight into the differences between the dynamics of lowland forests and those of montane forests. Montane forests had a lower annual rate of deforestation than did forests in the lowlands. Socio-economic, demographic and biophysical factors explain overall deforestation rates for the region. However, when altitude variation is taken into account, intraregional differences in the Andes become evident. Deforestation processes differ between those areas adjacent to the high Andean valleys where most of the country’s population concentrates and those areas in the tropical lowlands north, west and east of the Andean chain. Differences between lowland and montane forest dynamics are due partly to the accessibility of forests and differences in wealth and economic activities. In montane forests, deforestation is positively influenced by economic activity, the presence of protected areas and higher slopes. Deforestation in montane forests is negatively affected by tenure of small land parcels, road density, water scarcity and mean temperature. Lowland deforestation rates are more closely related to rural population, pasture percentage, crops, protected areas and temperature. Our results suggest that montane forests appear to be in a more advanced stage of colonisation and economic development, whereas lowland forests are closer to the colonisation frontier and to rapidly growing colonist populations. This study reinforces the idea that although the most common tropical drivers of deforestation are found in the Andes, these drivers operate differently when intraregional differences are considered.  相似文献   

17.
With globalization, virtual exchanges of natural resources embodied in traded commodities redistribute geographically land use and its environmental impacts. Benefits of national forest protection may be undermined at the global-scale by leakage through international trade. We studied land use displacement associated with national policies to protect forests in Bhutan. This case study provides a simple situation: a dominant forest cover almost unaffected by agricultural expansion, a rural economy dominated by the primary sector, centralized forest conservation policies, and a dominant trading partner. We assessed the net effects at the international level of the Bhutanese forest protection policies by accounting for trade in wood products with India. Our results show that these policies have been effective in maintaining a high forest cover, but have been accompanied by an increasing displacement of forest use to India. In 1996–2011, the difference between the total volume of wood imported from India and the total volume exported from Bhutan—i.e., the net displacement—corresponds to 27 % of the total volume consumed in Bhutan. In 2011, 68 % of the total forest area required to produce the wood consumed in Bhutan was located in India. The wood imported by Bhutan was likely originating from tree plantations in the northeastern Indian states. Since Bhutan has few tree plantations and very valuable natural forests, the net international-level ecological impacts of this land use displacement is arguably positive. Most of the wood imports of Bhutan were wood charcoal for its emerging chemical industries. This case of displacement reflects functional upgrading in the value-chain rather than an externalization of consumption-based environmental costs. Through its government policies, Bhutan has managed to support its economic development while protecting its forests and leapfrogging the negative impacts on forests generally associated with the early stages of modernization.  相似文献   

18.
Detailed observations of natural and anthropogenic disturbance events that impact forest structure and the distribution of carbon are essential to estimate changes in terrestrial carbon pools and the associated emissions and removals of greenhouse gasses. Recent advances in remote sensing approaches have resulted in annual and decadal estimates of land-cover change derived from observations using broad-scale moderate resolution imaging spectroradiometer (MODIS) 250 m–1 km imagery. These land-use change estimates, however, are often not attributed directly to a cause or activity and are not well validated, especially in tropical areas. Knowledge of the type of disturbance that caused the observed land-cover changes is important, however, for the quantification of the associated impacts on ecosystem carbon stocks and fluxes. In this paper, we provide estimates of the amount of forest land-cover change in a Mexican forested region and propose an approach for attributing the cause of the observed changes to the underlying disturbance driver. To do so, we collate geospatial and remote sensing data from a variety of sources to summarize statistics about the major disturbances within the Yucatan Peninsula, an “early action” region for the reduction of emissions from deforestation and degradation, from 2005 to 2010. We combine the datasets to develop rules to estimate the likely disturbances that caused the observed land-cover changes based on their spatially explicit location. Finally, we compare our observed disturbance rates to those detected using classified land-cover data derived from MODIS.  相似文献   

19.
The southern Yucatán has been identified as a deforestation hot spot. Land-change studies document the extent of forest loss at a regional scale, and case studies provide insights into the drivers of deforestation at the household level. Those studies have paid minimal attention to sub-regional analysis, especially to discrete land-management units above the household level. This analysis of upland forest change addresses the range of variation in deforestation among 96 ejidos (communal lands) and the Calakmul Biosphere Reserve, the two dominant land-tenure and land-management units in the region. Satellite imagery, census, and land-tenure data are used to establish the extent and location of deforestation patterns, and multivariate techniques are employed to identify biophysical and socioeconomic variables that explain such patterns. Results show that, for the 1984–1993 period, deforestation in the southern Yucatán was not as prevalent as implied by its hot spot designation. Three clusters of deforestation are identified. A logistic regression analysis establishes that size of forest holdings, population growth, and location in the precipitation gradient correlate with ejidos that experienced higher deforestation rates than the rest of the land-tenure units. For the 1993–2000 period, conservation programs and changes in the economic context of this “hollow frontier” contributed to reduce deforestation rates and extent. This analysis illustrates the spatio-temporal heterogeneity of much tropical forest change and caution that it should bring to simple formulations of modeling this change and prescribing policies to control it.  相似文献   

20.
Amazonia contains more carbon (C) than a decade of global, human-induced CO2 emissions (60–80 billion tons). This C is gradually being released to the atmosphere through deforestation. Projected increases in Amazon deforestation associated with investments in road paving and other types of infra-structure may increase these C emissions. An increase of 25–40% in Amazon deforestation due to projected road paving could counterbalance nearly half of the reductions in C emissions that would be achieved if the Kyoto Protocol were implemented. Forecasted emission increases could be curtailed if development strategies aimed at controlling frontier expansion and creating economic alternatives were implemented. Given ancillary benefits and relative low costs, reducing deforestation in Amazonia and other tropical areas could be an attractive option for climate mitigation. Projects that help contain deforestation and reduce frontier expansion can play an important role in climate change mitigation but currently are not allowed as an abatement strategy under the climate regime. Creating incentives for forest conservation and decreased deforestation can be a unique opportunity for both forest conservation and climate mitigation.  相似文献   

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