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1.
Autologistic regression and multicriteria evaluation models for the prediction of forest expansion 总被引：1，自引：1，他引：0
Dimitrios P. Triantakonstantis Dionissios P. Kalivas Vassiliki J. Kollias 《New Forests》2013,44(2):163-181
Land use changes are complex ecological processes driven by the interaction of biophysical and human related factors. The prediction of forest land use changes is important for sustainable forest management and biodiversity conservation. This study investigates the modelling process of the spatial dynamics of a forest ecosystem in north eastern Greece. For the prediction of forest expansion, based on land use data of the study area, a deterministic approach using logistic regression and heuristic methods of multi-criteria evaluation is adopted. The set of factors driving forest expansion are: the slope, the distance to roads, the distance to urban areas, the distance to forest, the soil depth, the soil erosion and the influence from the land uses of the neighbourhood. The spatial autocorrelation of driving factors is addressed using an autologistic regression model. The multicriteria evaluation approach is developed using weighted linear combination (WLC) and ordered weighted averaging (OWA) methods. In WLC method the relative importance of each factor was estimated using the analytical hierarchy process. In the OWA method, decision strategies are generated using a selection of relative linguistic quantifiers, which allow different Risk in decisions. The accuracy of the models produced was tested with real data for the year 2001 using the ROC validation method. All the methods produced satisfactory results. Autologistic regression showed slightly better performance than multicriteria evaluation methods due to higher degree of objectivity in defining the importance of driving factors for forest expansion. 相似文献
2.
Environmental functions of tropical forest can serve as criteria for forest conservation planning in the tropics. The objective
of this study is to evaluate the environmental functions of tropical forest in Kinabalu Park, Sabah, Malaysia, using GIS and
remote sensing techniques. Field data, statistical data, including weather data with geographic localities, maps and satellite
image are collected. Linear regression models are developed for forests of different geological substrates, based on the relationships
between altitude and biodiversity (Fisher’s alpha index). Biodiversity conservation function map is derived with the statistical
models and a digital elevation model. Coupling with extensive literature review, an evaluation matrix for evaluating soil
and water conservation functions including landslide prevention, flood prevention and drought prevention functions, is constructed.
To evaluate the soil and water conservation functions, a weighted linear combination method is used with GIS layers of topography,
geology, soil depth, rainfall and slope. Forest areas in Kinabalu Park are derived with land cover mapping using Landsat-TM
image. Areas having high values of biodiversity conservation, flood and drought prevention functions are covered with mainly
lowland rain forest. On the other hand, areas with high values of the landslide prevention function are covered with mainly
subalpine forests. Using the environmental functions, a conservation index is computed to represent forests that are important
to conservation. Based on theCI, the lowland rain forest receives highest priority in protection. In fact, it is located in the boundary areas of the park
and thus exposed to illegal activities.
This study would not be possibly accomplished without the map data as well as other data. 相似文献
3.
Ludmila La Manna Alina G. Greslebin Silvia D. Matteucci 《European Journal of Forest Research》2013,132(5-6):877-885
Cost-distance model analyzes the relative difficulty in reaching each spot of the landscape for the object or species under study. It calculates the effective distance, which is the Euclidian distance modified by the friction to movement through different landscape elements. This work deals with the application of cost-distance analysis in forest pathology, considering Austrocedrus chilensis root rot caused by Phytophthora austrocedrae as an example. In this case, cost-distance analysis was used to determine the relative difficulty for the pathogen to reach healthy forest patches from the patches that are presently diseased. Friction values were assigned on the basis of abiotic conditions, biological characteristics of the pathogen and host presence. Since cattle may be a vehicle for Phytophthora dispersion, three hypothetical situations of ranching were considered. Cost-distance application resulted useful to define minimum risk areas for conservation purposes. In the study case, minimum risk area strongly varied in response to cattle presence. This study provided valuable information for A. chilensis disease management and showed one of the broad applications of cost-distance analysis in forestry. 相似文献
4.
Wotlolan Dean L. Lowry John H. Wales Nathan A. Glencross Kevin 《Agroforestry Systems》2021,95(8):1519-1532
We present novel methods that use geographic information systems (GIS) and multi-criteria decision analysis (MCDA) to evaluate land suitability for a set of seven agroforestry crops, with the aim to differentiate relative land suitability and its potential to achieve different benefit goals for the Sigatoka Valley, Fiji. Our first model (Land Suitability) identifies optimal areas for each crop based on readily available edaphic and environmental cultivation criteria and common GIS datasets. The second model (Weighted Maximum) uses objective approaches for weighting the relative importance of target crops to derive a multi-crop suitability map. We use the analytical hierarchy process (AHP) technique (a form of MCDA) to identify the relative importance of five benefit types (i.e. agroforestry initiative goals/AHP Objectives). AHP criterion weights were used to map the most important crops for different agroforestry goals. Our methods are unique among GIS-MCDA applications of land suitability analysis in that our aim was to investigate and spatially evaluate land use suitability for multiple crops on a per-crop basis, whereas the aim of most GIS-MCDA land suitability analyses is to evaluate relative suitability (e.g. low, medium, high), evaluate potential for different land uses (e.g. production, intensive, or multifunctional) or land suitability for a single crop. We conclude that the methods described can be adapted to agroforestry initiatives and other similar land use suitability applications in the Pacific region and other geographical settings.
相似文献5.
延边林区通过实施天保工程,使森林资源得到有效保护,而且成功地调整了林业产业结构。要判定天保工程的实施效果,需要对其进行评价。根据科学性、可比性、可操作性和与政策的相关性相统一的标准,选定了森林覆盖率变化、森林蓄积量变化率、森林面积变化率、天然林面积变化率、水源涵养量变化、水土保持面积变化、湿地面积变化、固定温室气体量变化和释放氧气量变化9个评价指标,建立了森林生态效益评价体系。 相似文献
6.
G. Arturo Sánchez-Azofeifa Mauricio Quesada Pablo Cuevas-Reyes Alicia Castillo Gumersindo Sánchez-Montoya 《Forest Ecology and Management》2009
Tropical deforestation and habitat fragmentation in areas around conservation areas have been an important element for discussion in the conservation and policy-making community. In this paper, we evaluate land cover change processes around one of the most important tropical dry forest reserves in the Americas: the Chamela-Cuixmala Biosphere Reserve, Mexico. The analysis is conducted at three scales: regional scale (coast of the State of Jalisco), proximity to the reserve (via a 30-km buffer zone analysis), and inside the Biosphere Reserve. The proximity analysis is complemented by a unique data set that represents the extent and boundaries of Ejidos (local land management units) in the region. Results indicate that areas surrounding the reserve have low deforestation, with Ejidos and buffer areas having more forest cover as they get closer to the reserve. The nature of this important phenomenon is discussed in the context of the socio-economic conditions of the local communities. Our work suggests that the creation of a network of “Ejidos’ Conservation Areas”, in the context of an approach that will recognize payments for environmental services provided to local communities, could contribute to the conservation and maintenance of the rich biodiversity in a region that has one of the highest levels of endemism in the world. 相似文献
7.
《Journal of Sustainable Forestry》2013,32(1-2):49-71
Abstract Deforestation is often the primary threat to conservation goals in tropical countries. However, accessing the remote locations in which most remaining forests of conservation value occur makes it difficult to quantify deforestation trends and to galvanize preventive action. Using remotely sensed images we were able to quantify rates of forest loss in La Amistad Biosphere Reserve, Panama. Annual deforestation rates were low between 1987 and 1998 at 0.05% but increased nearly 12-fold between 1998 and 2001 to 0.6%. Net forest loss was 0.56% between 1987 and 1998 and 2.34% between 1998 and 2001. Deforestation rates differed significantly between protected areas. Protected areas on the Caribbean side of the Biosphere Reserve experienced greater levels of deforestation than those on the Pacific, even though both absolute and percent forest cover are higher on the Caribbean. Most forest conversion was for cattle pasture and an area of industrial cattle ranching was identified within the Palo Seco and PILA protected areas as a priority for enforcement activities. Forest conversion to pasture was highly correlated with proximity to roads, rivers, and villages (p < 0.001). The spatial scale of correlation varied between feature types, suggesting a greater area of impact from roads and towns versus rivers. The acceleration of forest conversion from 1998 to 2001 confirms the negative ecological impact of the recent increase in population and development pressure in this previously isolated region. 相似文献
8.
While riparian vegetation can play a major role in protecting land, water and natural habitat in catchments, there are high
costs associated with tree planting and establishment and in diverting land from cropping. The distribution of costs and benefits
of riparian revegetation creates conflicts in the objectives of various stakeholder groups, and elicitation of importance
weights of objectives and determination of rankings of a number of policy options by these stakeholder groups becomes critical
in decision-making. The analytic hierarchy process (AHP) is a multicriteria analysis technique that provides an appropriate
tool to accommodate the conflicting views of various stakeholder groups. The AHP allows the users to assess the relative importance
of multiple criteria (or multiple alternatives against a given criterion) in an intuitive manner. This paper presents an application
of AHP to obtain preference weights of environmental, social and economic objectives which have been used in ranking riparian
revegetation policy options in a small catchment (watershed) in north Queensland, Australia. The preference weights towards
environmental, economic and social objectives have been obtained for the various stakeholder groups (landholders, representatives
of local sugar mill staff, environmentalists, recreational fishers and the local community). The AHP technique has proved
useful in eliciting objectives and ranking policy options as well as in checking for consistency of the statements of stakeholder
groups. Implementation of this approach requires a complex data elicitation process. 相似文献
9.
Large areas assessments of forest biomass distribution are a challenge in heterogeneous landscapes, where variations in tree growth and species composition occur over short distances. In this study, we use statistical and geospatial modeling on densely sampled forest biomass data to analyze the relative importance of ecological and physiographic variables as determinants of spatial variation of forest biomass in the environmentally heterogeneous region of the Big Sur, California. We estimated biomass in 280 forest plots (one plot per 2.85 km2) and measured an array of ecological (vegetation community type, distance to edge, amount of surrounding non-forest vegetation, soil properties, fire history) and physiographic drivers (elevation, potential soil moisture and solar radiation, proximity to the coast) of tree growth at each plot location. Our geostatistical analyses revealed that biomass distribution is spatially structured and autocorrelated up to 3.1 km. Regression tree (RT) models showed that both physiographic and ecological factors influenced biomass distribution. Across randomly selected sample densities (sample size 112 to 280), ecological effects of vegetation community type and distance to forest edge, and physiographic effects of elevation, potential soil moisture and solar radiation were the most consistent predictors of biomass. Topographic moisture index and potential solar radiation had a positive effect on biomass, indicating the importance of topographically-mediated energy and moisture on plant growth and biomass accumulation. RT model explained 35% of the variation in biomass and spatially autocorrelated variation were retained in regession residuals. Regression kriging model, developed from RT combined with kriging of regression residuals, was used to map biomass across the Big Sur. This study demonstrates how statistical and geospatial modeling can be used to discriminate the relative importance of physiographic and ecologic effects on forest biomass and develop spatial models to predict and map biomass distribution across a heterogeneous landscape. 相似文献
10.
Fabrício Alvim Carvalho João Marcelo Alvarenga Braga Marcelo Trindade Nascimento 《林业研究》2016,27(3):605-609
This study describes the tree community structure of three moist lowland Atlantic Forest fragments in Rio de Janeiro State, southeastern Brazil. Two fragments were disturbed and an undisturbed one was used as reference. Our hypothesis was that disturbed fragments show distinct structural patterns in comparison with undisturbed stands due to past disturbance practices and forest fragmentation. Four 100 ×5 m sampling plots were demarcated in each fragment and all live and dead trees with DBH C 5 cm were located, measured and identified. The results supported our hypothesis, due to the high values found for standing dead trees, an increase of dominance of a few pioneer species, lower values of large trees and species richness in disturbed fragments in comparison with the undisturbed one. The advanced fragmentation process in the Southern Brazilian lowland areas and the high species richness in undisturbed areas highlight these forest fragments as priority areas for conservation and management. 相似文献
11.
The suitability of plantation monocultures for the conservation of forest animals is an issue under continous debate. The adaptability of forest dwellers and the forest management regime seem to play key roles. In this study, I investigated the habitat selection of a generalist bird, the great spotted woodpecker (Dendrocopos major), within a pine (Pine spp.) monoculture, as well as the importance of the native habitat features within the pine matrix for the species’ conservation. I compared 52 plots with woodpecker presence against 121 plots where the species was absent, as well as 68 nest-trees against 90 random ones. Regression analyses were used to investigate the habitat attributes involved in the habitat selection. Although the great spotted woodpecker is considered a generalist forest dweller, it shows a marked habitat selection. Based on presence/absence records, the woodpecker prefers well-forested patches with high levels of tree diversity and with good coverage of a secondary species such as the strawberry tree (Arbutus unedo). To excavate their nests, woodpeckers select large trees in patches where other trees are also larger, rejecting patches with a high number of small trees. The most striking conclusion from this work is the preference shown for native trees, especially Portuguese oaks (Quercus faginea), as nest-trees. This is noteworthy because native trees are smaller and they are surrounded by smaller trees than pines. These findings support that woodpecker conservation benefits from an increase of habitat heterogeneity, particularly by the retention of native woodland patches within the plantation matrix. 相似文献
12.
城市生物多样性保护是食物生产、人类健康和城市安全的必要保障,生态安全格局的构建能够维护自然生态平衡、保持生境稳定性和提高景观连通度,是生物多样性保护的重要空间途径。以吕梁市为例,采用形态学空间格局分析法和景观连通性指数法定量评估生态斑块重要性,辨别生态源地,利用最小累积阻力模型提取生态廊道和战略点,构建市域生物多样性保护的生态安全格局。结果表明:景观格局中核心区、桥接区、孤岛为林地和水域要素主要构成;沿吕梁山脉带状分布的生态源地景观连通性较大,西部生态源地面积较小且斑块重要性相对较低;"两纵,多横"的生态廊道布局和战略点布设,有效提高了市域生态结构的完整性。研究结果可以为市域尺度生物多样性保护规划提供思路和方法。 相似文献
13.
14.
《Forest Policy and Economics》2000,1(3-4):209-223
Forestry has transformed the tree species composition and structure of Swedish forests. The fragmented ownership pattern in areas with non-industrial private forest ownership (NIPF), in combination with these forestry practices, have created fragmented forests with relatively low proportions of habitat types important to many species. Ecological landscape planning has been suggested and tested as a mean for integrating nature conservation and timber production in Sweden. However, ecological landscape planning concepts have been developed for areas with homogenous ownership patterns and not for areas with fragmented ownership. In this study, stands that are voluntarily set aside by individual forest owners were examined in terms of nature conservation value, and compared to randomly selected stands obtained by Monte Carlo simulation. In order to obtain rather detailed data about the set-aside stands, semi-standardized interviews were carried out directly with forest owners in three landscape areas dominated by NIPF. The interviews showed that 26 out of 29 forest owners could locate some stands where they did not have high requirements for timber yield. These stands had higher than average local and spatial nature conservation value as a result of stand structure, composition and location in the landscape. The stands did not have a random location or size, being found closer to key habitats as well as forming equally large or larger patches than other stands. These stands are suggested to form a basis for ecological landscape planning as forest owners seem to have some kind of ‘common view’ of which stands to set aside. This common view could be used to coordinate the contribution made by individual forest owners to nature conservation in areas with fragmented ownership patterns. 相似文献
15.
Rafael Moreno-Sanchez Juan Manuel Torres-Rojo Francisco Moreno-Sanchez Sue Hawkins Justin Little Susan McPartland 《林业研究》2012,23(4):529-541
Forest managers and policy makers increasingly demand to have access to estimates of forest fragmentation,human accessibility to forest areas and levels of anthropogenic pressure on the remaining forests to integrate them into monitoring systems,management and conservation plans.Forest fragmentation is defined as the breaking up of a forest unit,where the number of patches and the amount of expose edge increase while the amount of core area decreases.Forest fragmentation studies in Mexico have been limited to local or regional levels and have concentrated only on specific forest types.This paper presents an assessment of the fragmentation of all forest types at the national level,their effective proximity to anthropogenic influences,and the development of an indicator of anthropogenic pressure on the forests areas.Broadleaf forests,tropical evergreen forests and tropical dry deciduous forests show the greatest fragmentation.Almost half(47%) of the tropical forests are in close effective proximity to anthropogenic influences and only 12% of their area can be considered isolated from anthropogenic influences.The values for the temperate forests are 23% and 29% respectively.Anthropogenic pressure in the immediate vicinity of anthropogenic activities is much higher in the tropical forests(75 in a scale 0-100) than in the temperate forests(30).When considering these results jointly,the tropical forests,and more specifically,the tropical evergreen forests and tropical dry deciduous forests are under the greatest pressure and risks of degradation. 相似文献
16.
The relationship between abiotic and biotic factors and the spread of the European spruce bark beetle, Ips typographus (L.), was investigated at a landscape level over a model period of 18 years in the Bavarian Forest National Park in Germany. Deadwood areas - where I. typographus - caused tree mortality of 100% - were photographed annually using Color-infrared aerial photography and digitally recorded in vector form. Thirty-two static and dynamic habitat variables were quantitatively determined using spatial pattern analysis and geostatistics from 1990 to 2007 at the landscape scale. The importance of the presence of deadwood areas for thirty-two habitat variables for the occurrence of the bark beetle was quantitatively recorded using an Ecological Niche Factor Analysis (ENFA).It was shown over a long model period that the intensity of the bark beetle infestation went through different phases over the 18-year study period. No mono-causal correlations could be found between individual habitat factors and the spread of the bark beetle over the entire model period. On the one hand, these findings underline the complexity of the system, on the other hand, this could be interpreted as a possible explanation for conclusions drawn by previous studies that differ from each other.The importance of individual habitat variables and the combinations of variables varied to different extents within these phases. An examination of the cumulative importance of the habitat demonstrated that the biological structural variables such as the distance from the site of the previous year's infestation, the area and the perimeter of the infested areas from the previous year are of great importance for the incidence of the bark beetle, but not across all years. Of equal significance for assessing the size of the area and the distance of the deadwood areas from the sites of the previous year's infestation are the size of the areas, the perimeter of the deadwood areas and the proximity index. An evaluation of the stages of forest succession showed that cumulatively, a short distance between the infested areas and the forest areas with conifers in the early stages of growth was an equally important habitat factor from 1990 to 2007. By quantitatively recording habitat factors that are significant for the spread of the bark beetle it may help predict areas that are at risk and thus to develop suitable management strategies to minimise or stop the spread and the effect of the bark beetle. 相似文献
17.
基于3S技术和AHP的南京市城市森林生态服务功能评价 总被引：4，自引：0，他引：4
基于南京市城市森林资源状况和指标体系的科学性、动态性、可行性原则指导,建立生态服务功能评价指标体系。基于3S技术获得2000年和2007年各指标因子量化的可靠基础数据,用层次分析法(AHP)分析影响森林生态服务功能的主导因子和相互关系,采用权重加权法最终评级。结果表明,近年来南京市森林生态建设卓有成效。 相似文献
18.
Live fences are common elements in neotropical agricultural landscapes and could play important roles in the conservation
of biodiversity by enhancing landscape connectivity, however, little is known about their abundance and spatial arrangement.
The objectives of this study were to characterize the abundance and spatial patterns of live fences in a fragmented landscape
dominated by pastures in Río Frío, Costa Rica, to determine their contribution to landscape structure and connectivity and
to examine their role as tools for landscape conservation planning. Live fences accounted for 45.4% of all fences in the landscape
and occurred with a mean density of 50.5 linear meters per hectare. Although live fences covered only a small total area of
the landscape (<2%), they had an important effect on landscape structure and connectivity, increasing total tree cover, dividing
pastures into smaller areas, creating rectilinear networks that cross the landscape and providing direct physical connections
to forest patches. Simulations showed that the conversion of all existing wooden fences to live fences would greatly enhance
landscape connectivity by more than doubling the area, density and number of direct connections to forest habitats, and reducing
the average distance between tree canopies. Our study demonstrates that live fences play key roles in defining the structure
and composition of neotropical agricultural landscapes and merit consideration in both conservation efforts and agricultural
policies designed to enhance landscape connectivity and promote biodiversity conservation. 相似文献
19.
以层次分析法为基础,对城市绿地应急避难场所进行实地考察,选取城市绿地应急避难能力为目标层(Z),场所的规划设计(B1)、基础设施条件(B2)、管理维护(B3)为准则层,并相应选取场地周边环境等18个因子为指标层(C),建立AHP评价模型。采用1～9标度法为各因子打分,求出各因子的相对权重和合成权重;邀请专家为避难场所打分,结合合成权重计算出避难场所的应急避难能力得分并划分等级;未达满分的应急避难场所要求要计算出各个因子的影响力并进行排序,找出薄弱环节加以改进。并以福州市温泉公园为例,计算出其综合应急能力为82.7分,属于A级;通过δ值的计算得出:温泉公园的周边环境、应急避难指挥中心、应急物质储备室、监控系统等方面需要进一步改善。 相似文献
20.
Factors related to the composition of riparian forest stands on three streams in the northern Sierra Nevada mixed conifer forest type were related to proximity to the water course and years since fire. Using a linear regression analysis 46 variables were correlated to the natural log of distance from the thalweg “ln(distance)” including a highly significant positive correlation to dominance and percent canopy cover of conifers, and a significant negative correlation to the same variables when applied to hardwoods. Twenty six variables were correlated to years since fire “years” including similar correlations to the dominance and cover of hardwood and conifer species. However, the significance of the correlation and the degree of sample variability described by fire age was relatively low in comparison to that found for distance from the thalweg. In addition the relative frequency of fire scars increased in a linear fashion with distance from the watercourse. The results of this study indicate that the importance of fire as a determining influence on forest composition declines in proximity to the riparian zone. 相似文献