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1.
The protection of agricultural land and forests is a relatively new concept in Poland, and it began with forest protection in the 1920s. The first regulations on the protection of agricultural land were introduced only in the 1960s. Agricultural land and forests received comprehensive protection pursuant to the provisions of the Act of 26 October 1977 on the protection of agricultural land, forests and land recultivation. This legal act set the foundations for the protection of farmland and forests in successive decades.The aim of this study was to determine the influence of farmland and forest protection on spatial planning and to highlight the loss of agricultural and forest land resulting from conversion to other purposes. Legal regulations pertaining to spatial planning and the protection of agricultural and land forests were analysed. The scale of the problem was identified, and future land-use types were forecast based on the data developed by Statistics Poland (GUS). The existing spatial plans (municipal master plan - MMP) were analysed to determine the conversion loss index (CLI) associated with the conversion of agricultural land and forests to other uses. Legal regulations pertaining to the protection of agricultural land and forests were also analysed, and the extent of the relevant conversion measures was determined. The study demonstrated that urban development and the inevitable urbanization of rural areas contribute to the loss of agricultural and forest land that are converted to other uses.  相似文献   

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3.
The Chinese government applies the term ‘tree crops’ (jingjilin) to a bundle of tree species with uses other than timber production, defining this category as a component of national forest statistics. Tree crops may displace either farmland or forestland, and can be a promising livelihood option for smallholders. The overall impact of this particular policy on natural forest growth remained unanswered. In the general expansion trend of tree cover in southern China, tree crops could compete for land with natural forests, their cultivation may pose environmental trade-offs with natural forest cover. However, in a context of large labor flows from countryside to cities, tree crops could provide promising opportunities for dealing with on-farm labor shortages and generating income for disadvantaged populations remaining in rural communities, then promoting remaining natural forest quality through alternative livelihoods process. There is a knowledge gap to thoroughly investigate tree crops’ impact on natural forest change both conceptually and empirically, especially a mechanism verification of the alternative livelihood hypothesis. Thus, we construct a framework assessing land use competition and alternative livelihood effects together to assess overall impacts of tree crop cultivation on natural forests. Our dataset combines forest resource inventory data and provincial social-economic factors for a panel analysis of contributions to change in natural forest cover, density, and stock in China’s biodiversity-rich southern provinces. Results show tree crop cover is negatively associated with natural forest extent, but positive associated with change in natural forest density, while the relationship with change in natural forest stock is insignificant. Further tests of mechanisms support the hypothesis that tree crops benefit disadvantaged rural populations, providing an alternative livelihood. Defining tree crops as forest in China obscures important patterns, particularly a trade-off between tree crops and natural forest cover and a possible synergy with natural forest density mediated by alternative livelihood processes. Policy makers should enact specific policies to incentivize natural forest recovery in the southern collective forest zone and reconsider the appropriateness of defining tree crops as forest. Concentration and intensification of tree crop production on suitable lands may have the potential to benefit both forests and impoverished populations.  相似文献   

4.
Recent land cover change estimates show overall decline of tropical forests at the regional and global scales caused by multiple social, cultural and economic factors. There is an overall concern on the prevailing land use practices, such as shifting cultivation and extraction of forest materials as agents of forests losses, but also new, emerging land uses are threatening tropical forests. Understanding of the long-term development and driving forces of forest changes are needed, especially at local levels where many decisions on forest policies and land uses are made. This paper addresses the importance of such information for improved estimates of forest dynamics by studying local level land cover and land use changes during the last 50–70 years in the Eastern African tropical island of Zanzibar, Tanzania. The paper discusses the role of traditional and new land uses mainly subsistence farming, tourism and government interference through tree planting, in the long-term development of the forests at the village level. The material for the study is gathered from the interpretation of archival maps and aerial photographs combined with contemporary digital aerial photographs. The analyses are based on the mapping, spatial sampling and spatio-temporal change trajectory analysis (LCTA) of forest land cover, forest land uses and settlement patterns with GIS and statistics. Six distinct forest land cover change trajectories were identified and these illustrate dynamic and heterogeneous nature of the forests. Closed forest cover has dominated throughout due to cyclical land use patterns, but over 70% of the land area has been continuously transforming between closed, semi-open and open land cover conditions. Land use turnover rates indicate that hardly any forest areas are left untouched from the forces, which remove and re-establish forest vegetation in the long run. Land cover and land use change trajectories are spatially fragmented in the studied landscape. Majority of forest loss-gain dynamics is caused by shifting cultivation, while forest losses are most dramatic along the coast, where traditional and new land uses meet and land uses pressures are highest. The study suggests that landscape change trajectory analyses, where contemporary and historical information on land uses and land cover changes are spatially linked, can provide valuable aspects into local level forest land use planning and management strategies. For the case study, the findings suggest the following key forest management strategies for consideration: (1) establishment of a protected forest/scrubland in participation with the local stakeholders, especially the farmers, (2) promotion of areas for permanent agricultural practices, while simultaneously introducing management controls in the traditional slash-and-burn farming areas, and (3) promoting new livelihood opportunities for the farmers, who have traditionally been dependent on forest resources, meanwhile introducing alternatives for fuel wood for cooking.  相似文献   

5.
Co-governance of forests, or participatory forest management, has been a wide-spread conservation and development (C&D) intervention in India for over two decades. The practice began in the 1990s as Joint Forest Management (JFM), where local communities – organised into forest protection committees (FPCs) – worked in cooperation with various state forest departments. Later on, this intervention took shape of Community Forest Management (CFM), where communities managed their forests largely independent of the forest departments. Under both the JFM and CFM models, gender mainstreaming – enabling equal distribution of opportunities and services across genders – held a pivotal position. This study shows that despite continued marginalisation, female FPC members often performed as if initiatives were successful. Thus, the central question investigated in this paper is: "Why women performed success in participatory forest management interventions while experiencing marginalisation in the FPC?” This paper adopts an ethnographic case study methodology (immersion), utilising in-depth ethnographic case studies from three states of India for analysing performances of success and the resulting dynamics of participation, to explain the gendered nuances of the grassroots conservation and development interventions. The concept of 'situated agency' of community actors is explored to understand the practices around the performances of success in C&D interventions in forest-dependent communities in India. The paper argues that these performances hold the promise of a slow, but steady progress towards the creation of a gender-sensitive system in an otherwise patriarchal social structure.  相似文献   

6.
从森林旅游的人地关系机理入手,分析了森林旅游的生态伦理关系,结果表明:森林因其陆地生态系统的主体地位,在开发利用与生态环境保护之间存在着一定程度的矛盾,且当前森林旅游开发中产品低级、雷同单一等问题突出,无法满足游客多样化的需求。鉴于这种矛盾本质上是人地关系矛盾,而提出旅游开发与森林生态保育相结合、森林生态环境利用与生态文明建设相结合、市场导向与引导市场相结合3条原则,并围绕"人"、"地"需求及其关系协调,设计了解决旅游地布局、森林景观建设、旅游项目和旅游产品4个层面涉及的主要问题的绿色开发路径。  相似文献   

7.
Protection of biodiversity under conditions of climate change is likely to place large requirements on existing frameworks for biodiversity protection at both EU and national level. While these systems are not perfectly adapted today, the inclusion of climate change concerns will require revision and addition of new issues, such as species migration corridors and buffers, as well as proactive strategies in areas that may not be protected today. Biodiversity in forest is particularly important as forest range over large areas that include also other land uses; this holds particularly true for the large forested areas in northern Europe. Illustrating complexities regarding biodiversity protection, this study reviews the applicable legal framework related to biodiversity in forests on EU and national level in Sweden, one of the countries with the largest forest areas in the EU. Mainly drawing on a policy and legal study, the paper concludes that adapting the legislative and policy system to a future with large uncertainties in terms of extent of change poses a problem for what are largely reactive systems in particular in terms of legislation.  相似文献   

8.
Tropical deforestation has heightened the need for effective governance of protected areas aimed at conserving natural resources, biodiversity, and ecosystem services. The southern highlands of Ethiopia hold some of the largest expanses of contiguous tropical forest in Ethiopia. This area also is undergoing rapid land conversion. Multiple protected areas with different management strategies and objectives have been established, in part, to conserve forests and the ecosystem services they provide. We examined four types of protected areas; a national park, a state-run forest enterprise, two occupied privately leased hunting concessions, and two unoccupied hunting concessions, to evaluate their effectiveness at protecting forest cover. We used 1509 field plots with medium-resolution Landsat imagery from 1987 to 2015 to develop models of forest cover at approximately five-year time intervals. We found protected areas that were actively managed for timber production or hunting were more effective at conserving forest cover than the national park and the unoccupied hunting concessions. Over the study period, net forest cover change was −7.8% for the national park, 12.9% for the state-run forest enterprise, −0.2% and 13.3% for the occupied hunting concessions and −14.0% and −13.0% for the unoccupied hunting concessions. We also discuss how the change in forest cover relates to historic political events. In places like Ethiopia where the federal resources needed to conserve forests are limited, promoting a network that includes both federally and non-federally managed protected areas can result in more area and forests under protection.  相似文献   

9.
我国的森林生态效益补偿制度在法理上存在明显的法律冲突问题。在这种情况下,地方如何因地制宜完善森林生态效益补偿制度是一个值得研究的问题。介绍福建省在完善森林生态效益补偿制度方面的一些具体做法,如下游补上游的创新,超前的分级保护,补偿类别的细分。对这些做法进行法律评价:下游补上游是市县政府履行一部分补偿基金筹集职责的好办法;比国家早四年多提出对公益林的保护分三个等级;分析存在的不足,如没有补偿标准的增长机制,补偿标准大幅落后于相邻省份;模仿中央财政管护补偿的模式,使得征用补偿落空;国有公益林得到了不应得的征用补偿(即产权损失补偿);没有专门的公益林补偿管理机构;公益林补偿基金管理办法的位阶不合法。  相似文献   

10.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment.  相似文献   

11.
Urbanization is currently a major force in tropical land use transitions as economic activities aggregate in urban centers, particularly in Asia. This paper examines relationships among urbanization, household energy source, and forest cover at the state level in India using available census, survey, and remote sensing analysis from the 1990s and 2000s. Central questions include (1) how rapidly are urban and rural households switching from traditional to modern fuel sources; and (2) what are the consequences of changing household energy sources for fuelwood demand and forest cover. Country-wide, 30 and 78% of urban and rural households respectively used fuelwood for cooking in 1993. In urban households, the percentage decreased to 22% by 2005 with a shift towards liquefied petroleum gas (LPG). The shift occurred across almost all income classes. In rural areas, the use of LPG increased fourfold but 75% of households still rely on fuelwood. Despite the decline in percentage households using traditional fuels, fuelwood demand continued to increase from 1993 to 2005 at a national scale due to an increasing total number of households. However, 25% of states and union territories experienced declines in rural fuelwood demand and over 70% declines in urban fuelwood demand. Forest cover has remained steady or increased slightly over the time period, reaffirming the conclusion that fuelwood demand may lead to local degradation but not large-scale deforestation. At the state level, increases in percent forest cover between 2000 and 2004 are positively associated with percent of total households that are urban (corresponding to fewer percentage households using wood) but not related to changes in fuelwood demand. Plantations are a primary cause of increases in forest area, where benefits to ecosystem services such as biodiversity and hydrologic function are controversial. Results suggest that households will continue to climb the energy ladder with future urbanization, resulting in substantial development benefits and reduced exposure to indoor air pollution. Implications of reduced fuelwood demand for forest cover are less certain but the limited data suggest that urbanization will promote a transition to increasing forest cover in the Indian context.  相似文献   

12.
Concern for global warming has focused attention on the role of tropical forests in the reduction of ambient CO2 levels and mitigation of climate change. Deforestation is a major land use change in the tropics, with forest resources undergoing degradation through the influence of logging and conversion to other uses. Land use change is a product of varied local and regional resource use policies. Management of forest resources is one such major temporal factor, influencing resource stability and the carbon pool. Under a given management policy, both the long period of forest growth, and the slow turnover and decay of the carbon pool, enhance the relevance of stand level management policies as cost-effective mechanisms mitigating climate change. Apart from regional level uncertainties like the nature of land use and the estimation of carbon storage in vegetation and soil, the carbon flux of tropical forests is greatly influenced by uncertainty in regenerative capacity of forests and in harvest and management policies. A case study from India is used to develop a transition matrix model of natural forest management, and to explore the economic implications of maintaining and expanding existing carbon sinks. The study further explores the significance of investments in additional carbon sinks in plantation forests, given continued uncertainty in natural forest management.  相似文献   

13.
Satellite data-driven discoveries are fuelling the literature on forest transitions, particularly in quantifying slow, large-scale trends. Mather’s forest transition concept depicts the inflection point marking a change from decreasing to increasing forest area. This theory is being elucidated using satellite images of global forest cover from the National Aeronautics and Space Administration of the United States (NASA), the European Space Agency (ESA), and now from the FAO’s recently introduced geospatial monitoring platform SEPAL 2.1. Recently, a series of high profile papers have illuminated the concept of the forest transition using analysis of remote sensing-based forest cover images. Defined as an increase in global forest cover, analysis of satellite images over the past thirty years suggests that a global forest transition has occurred. However, satellite data provide less information about biodiversity and carbon sequestration outcomes in new forests. Incorporating other data sources on the quality of forest transitions offers the potential to develop better reforestation programs, address climate change goals and enhance other ecological and human benefits. This article presents a view on remote sensing, biodiversity, and carbon science that has changed the study of forest transitions, and an outline of anticipated and suggested science and policy directions.  相似文献   

14.
基于随机森林算法的洪水灾害风险评估研究   总被引:1,自引:0,他引:1  
陈军飞  董然 《水利经济》2019,37(3):55-61
根据流域灾害系统理论,在考虑致灾因子、孕灾环境和承灾体的基础上,选取9个风险评价指标,运用样本数据进行人工识别风险并得到训练样本,采用随机森林算法构建基于随机森林的洪水灾害风险评估模型。然后采用随机森林自评估工具,分析建立的洪水灾害风险评估模型的误差和指标,同时构建支持向量机模型作为对比方案,并采用五折交叉验证方法对基于随机森林算法的洪水灾害风险评估模型和支持向量机模型进行验证。最后以海河流域邱庄段为研究对象,分别运用基于随机森林算法的洪水灾害风险评估模型和基于支持向量机模型对相同的数据集进行评估和对比,结果显示,12 h内降雨总量、洪水持续时间和土壤含水量是引发洪水的主要因素,而基于随机森林算法的洪水灾害风险评估的训练精度及测试精度均高于支持向量机模型。  相似文献   

15.
Land use and land cover changes play an important role in the occurrence of vector-borne diseases. It is highly essential to identify the prominent changes responsible for its occurrence so that suitable measures can be adopted. An attempt was made to identify the prominent land use and land cover changes responsible for the spread of chikungunya, malaria, and dengue fever in the State of Kerala, India, using hierarchical cluster analysis and multiple regression analysis. Large extent of water bodies, low land and agricultural land played a significant role on the incidence of chikungunya and malaria. High population density, built-up area and agricultural area favoured dengue fever. Vector-borne diseases were found to be the lowest in places where there is no low land and with higher forest area. Inappropriate disposal of wastes generated in the built-up area might be the reason for the spread of dengue fever. Freshwater in drains of these areas is polluted and form breeding grounds for mosquitoes. Hence much attention is to be paid to provide appropriate treatment and disposal of wastes generated in the built-up area of the State In an evolving urban policy, priority is to be given to the installation of safe treatment and disposal facility of wastes especially, sewage, sullage, and solid waste. The protection of forest land also plays an important role. Economic policy instruments such as Payment for Environment Services (PES) schemes, may constitute a useful tool to encourage an improved land use management through appropriate price signals, such as, for instance, for the preservation of forested areas especially in proximity of highly populated urban environments.  相似文献   

16.
Seasonally dry tropical forests (SDTF) are exposed to numerous threats stemming from human activity and are considered a high conservation priority globally. Nevertheless, planning the conservation, management, and restoration of forests requires a detailed regional understanding of current forest distribution, and patterns and attractors of deforestation. We explored SDTF cover in the state of Veracruz, Mexico, where little is known about this type of forest since it was erroneously considered to have been eliminated and thus has not be included in recent conservation planning in Mexico. A time-series of land use and land cover (LULC) maps, based on Landsat imagery from 1973 (MSS), 1990 (TM), and 2000 (ETM+), was used to analyze historical patterns of deforestation and fragmentation of SDTF in a priority watershed in central Veracruz. Stepwise logistic regression was used to identify the main attractors of forest loss. Maps based on higher resolution SPOT imagery (2007–2008) were used to determine the current extent of SDTF. Results from our LULC analysis revealed landscapes that were consistently dominated (>50%) by some combination of intensified land use including cattle pastures, rain-fed and irrigated agricultural lands, with closed SDTF cover fluctuating from 11.3 to 9.26% during the study period (1973–2007). Annualized rates of forest loss between Landsat images (1973 vs. 2000; −2.02%) and between Landsat and SPOT images (1973 vs. 2007; −0.59), were moderate to low, with historical records suggesting that most deforestation occurred more than a century ago before the Mexican revolution. Nevertheless, rates of forest loss varied considerable between different time periods, with slight reforestation initially (1.55%; 1973–1990), followed by a marked decline (−8.08%; 1990–2000), and finally a noticeable increases in forest cover (4.92%; 2000–2007) that corresponds with changes in public policy and trends in population migration. The number of forest patches tripled between 1973 and 2000 and the mean forest patch area decreased almost 80% over the same time period. Logistic regression analysis (1973–2000) indicated that the main attractors of closed forest transformation were proximity to gentle slopes, cattle pastures, and the hydraulic infrastructure needed for crop irrigation. Although SDTF is highly fragmented and perturbed, important remnants of this diverse native forest still persists in the region. Our findings are discussed in the context of future conservation and restoration efforts.  相似文献   

17.
Ireland has undergone a substantial afforestation programme in the last 20 years, resulting in the forest cover increasing from 4.8% of the land area in 1983 to a current level of 10%. This paper presents the results of a study undertaken to assess stakeholders’ perceptions of forestry in two case study areas in Ireland. The two areas, Shillelagh and Newmarket, were chosen because their demographic characteristics varied as did their history of forestry development. However, the current forest cover is similar in the two areas both in terms of species composition and extent. Qualitative techniques, involving interviews with stakeholders, were used. There were striking differences in the perceptions of forestry in the cases study areas. In Shillelagh, which had a longer history of forest cover and a more urbanized population than Newmarket, forestry was considered part both of the local history and traditional landscape. Forests were valued for their amenity and recreation functions rather than their economic function. In contrast, perceptions of forestry in Newmarket were negative. Forestry was considered to be an isolating agent which was not part of the landscape of the area. The forests were also considered to have negligible amenity value. These negative perceptions in Newmarket seem to be linked to the dominance of Sitka spruce, an exotic conifer, in the forests. Stakeholders expressed the desire that if forestry was to expand further in the area that it would be through the planting of broadleaf species rather than conifers. The fact that these negative perceptions did not emerge in Shillelagh despite it having a similar species composition is attributed to the more gradual rate of afforestation and thus landscape change in the area. The lack of consultation and approach to planning regarding afforestation proposals was identified as a key issue in Newmarket with stakeholders expressing the wish that they should be consulted more when afforestation was planned. Greater community involvement in the planning of afforestation proposals is recommended as a means of improving consultation and to help dispel negative perceptions. The paper concludes by highlighting that perceptions of forestry within an area are dynamic and are influenced by the history of forestry development in that area.  相似文献   

18.
Wetter areas of the Amazon basin exhibit lower rates of agricultural conversion. Previous analyses, using relatively aggregate data on land cover, have been unable to determine the extent to which this reflects limited access versus unfavorable agroclimatic conditions. This article uses census-tract level data for the Brazilian Amazon to relate forest conversion and pasture productivity to precipitation, soil quality, infrastructure and market access, proximity to past conversion, and protection status. The probability that land is used for agriculture or intensively stocked with cattle declines markedly with increasing rainfall, other things equal.  相似文献   

19.
The role of land tenure and Mennonites as drivers of deforestation in the Central Yucatan Peninsula has not been empirically assessed. We evaluate different drivers and their relationship to forest cover change between 1986 and 2015 and assess how land tenure and Mennonite communities impact forest cover loss in the Municipality of Hopelchen, Campeche, Mexico. This study shows that forest cover loss has increased in the last decade (2005–2015), and that land tenure regime type is associated with this loss. Throughout the study period, statistical comparisons show rates of forest cover loss were significantly higher in private and federal property compared to forests in ejidos (communal property). Forest cover loss in Mennonite private property was also significantly higher than in non-Mennonite owned private property. The role of land tenure and the expansion of the agroindustrial production model as major drivers of forest cover loss in the region provide important insight into developing municipal land use plans and conservation strategies to reduce deforestation. Programs, incentives and policy directed towards forest conservation in the region that typically target ejido communities, will need to consider the growing trend of private property expansion within federal lands and work more closely with private property owners including Mennonite communities if deforestation reduction programs are to be successful.  相似文献   

20.
Research on the dynamics of tropical forest land use and cover change (LUCC) has focused on the three scenarios: (1) deforestation/degradation; (2) settled, degraded areas in recovery, and (3) sparsely settled, expansive, intact forest. Through examination of a central Quintana Roo, Mexico case study we propose a fourth scenario of a ‘sustainable landscape’: an inhabited, productively used, forested landscape that nonetheless shows little change or net gains in forest cover over the last 25 years. We use Landsat images to demonstrate a low incidence of net deforestation, 0.01% for the 1984–2000 period, the lowest recorded deforestation rate for southeastern Mexico. Institutional innovations such as an agrarian reform process that established large common property forests for non-timber forest product extraction, and later innovations such as sustainable forest management institutions have driven the outcome of low net deforestation, added to multiple organizational processes that promote sustainable land use.  相似文献   

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