14 results
Search Results
2. Towards sustainable management of kelp forests: An analysis of adaptive governance in developing regimes for wild kelp harvesting in Scotland and Norway.
- Author
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Greenhill, Lucy, Sundnes, Frode, and Karlsson, Marianne
- Subjects
FOREST management ,KELPS ,HABITATS ,MACROCYSTIS ,SCIENTIFIC knowledge ,LEGAL instruments ,ECOSYSTEM services - Abstract
Kelp forests are highly productive habitats which support important marine species and ecosystem services including coastal protection and carbon storage. Demand is increasing for commercial products from wild and cultivated kelp, however questions remain on how harvesting of wild kelp can be managed and governed in a sustainable and adaptive way. This paper analyses and contrasts the institutional arrangements for wild kelp harvesting in Scotland and Norway by examining three recent governance processes through document analysis and participant observation. We investigate to what extent the regimes display three foundational aspects of adaptive governance: local governance and participation; the use of knowledge; and legal adaptive capacity. Industrial harvesting has been underway for decades in Norway but is not yet practiced in Scotland, although kelp availability and traditional usage are similar. In Scotland, following extensive public objection in response to proposed industrial harvesting, a legal restriction was adopted in 2019 that prohibits industrial harvesting of whole plants, and the regulatory regime remains under review. In Norway, governance of kelp harvesting is designed to be adaptive and inclusive through periodic review of regional harvesting regulations, yet has not been adjusted despite contestation from stakeholders. In both cases, adaptive governance processes are indicated but are not influential on outcomes. Our paper reveals several obstacles to knowledge-based adaptive governance in practice. First, it is insufficient to create the processes of engagement and participation - these must be empowered to influence governance and remain legitimate. In both cases, the regimes remain hierarchical and dominated by central agencies, even though structures for local governance are available. Second, integrating scientific and local knowledge was shown to be difficult, and mechanisms to debate and negotiate risks and benefits were lacking. In each case, diverging perspectives on kelp harvesting were sustained even though final outcomes were reached, and consensus was elusive. Third, adaptive capacity of applicable legal instruments is of crucial importance, with differences apparent in capacity to enable on-going revision (as in Norway) and limit future change (in Scotland). Poor co-ordination between legal instruments also leads to complications between actors with different mandates and policy objectives. Recommendations are made for an adaptive approach to protect and manage kelp as a critical habitat. • Kelp supports diverse ecosystem services and is a contested resource. • Opportunities for adaptive governance exist but hierarchical regimes dominate. • Informal networks are powerful and can influence the highest level of government. • Arenas for balanced debate and negotiation across scales are needed. • Independent actors are needed to broker inclusive adaptive management. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
3. Modelling weed and vine disturbance in tropical forests after selective logging and clearcutting.
- Author
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Cazzolla Gatti, Roberto
- Subjects
- *
FOREST management , *CLEARCUTTING , *PLANT diversity conservation , *HABITATS , *FRAGMENTED landscapes , *BIOLOGICAL extinction , *ECOLOGICAL disturbances - Abstract
Although tropical rainforests preserve high levels of biodiversity, they are among the most threatened ecosystems globally due to large-scale fragmentation as a result of anthropogenic activities. Overall, fast human-driven habitat destruction is suspected to be one of the major causes of species extinction. The mosaic of vegetation types, which contributes to the incredible diversity of the tropics is highly impacted by large-scale fragmentation. The main causes of such habitat fragmentation are selective logging for valuable timber and agricultural clearance. The knowledge of the short and long-term effects of removing selected species in the tropical rainforests are scarce and need to be further investigated. Some studies about the effects of tropical forest disturbance in the short term have been conducted, but in the long term, there is limited knowledge. In this paper, I consider a system of coupled ordinary differential equations (ODEs) that modelled the dynamics of tropical rainforest subject to selective logging to understand how and why weeds and vine displace and limit tree species. From the empirical data collected on canopy height and plant diversity and the model proposed, I have the evidence of a decreasing tree diversity in tropical forests subject to management in comparison with to the same but untouched forests. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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4. Habitat network assessment of forest bioenergy options using the landscape simulator LandSim – A case study of Kronoberg, southern Sweden.
- Author
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Pang, Xi, Mörtberg, Ulla, Sallnäs, Ola, Trubins, Renats, Nordström, Eva-Maria, and Böttcher, Hannes
- Subjects
- *
FOREST biomass , *HABITATS , *RENEWABLE natural resources , *BIODIVERSITY conservation - Abstract
Forest biomass is a renewable resource that is increasingly utilised for bioenergy purposes in Sweden, which along with the extraction of industrial wood may conflict with biodiversity conservation. The aim of this paper is to present a method for integrated sustainability assessment of forest biomass extraction, particularly from bioenergy and biodiversity perspectives. The landscape simulator LandSim was developed and linked with models for the assessment of biomass yields and habitat networks representing prioritised biodiversity components. It was applied in a case study in Kronoberg County in southern Sweden. Forest growth and management were simulated for the period 2010–2110, following two land zoning scenarios, one applying even-aged forest management on all forest land except for protected areas (EAF-tot), and one applying continuous cover forest management on parts of the forest land, combined with protected areas and an intensified even-aged management on the other parts (CCF-int). The EAF-tot scenario implied higher yields of biomass feedstock for bioenergy, the CCF-int scenario only giving 66% of that yield, while the CCF-int scenario performed substantially better when it came to the habitat network indicators, if habitat suitability was ensured. Conclusively, the case study confirmed that the modelling framework of the LEcA tool, linking the landscape simulator LandSim with the biomass yield assessment and the habitat network model can be used for integrating main policy concerns when assessing renewable energy options. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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5. Trends in management of the world’s forests and impacts on carbon stocks.
- Author
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Birdsey, Richard and Pan, Yude
- Subjects
FORESTS & forestry ,FRAGMENTED landscapes ,LAND use ,BIODEGRADATION ,HABITATS - Abstract
Global forests are increasingly affected by land-use change, fragmentation, changing management objectives, and degradation. In this paper we broadly characterize trends in global forest area by intensity of management, and provide an overview of changes in global carbon stocks associated with managed forests. We discuss different interpretations of “management” and highlight some important accounting and analysis issues. The area of global forests has declined by 3% since 1990 but the area of planted forest has increased in all regions of the world and now accounts for almost 7% of global forest land. The area of primary forest, which is typically defined as lacking direct human influence, is about 34% of all forest land according to country reports, but the area is declining especially in South America and Africa because of human-caused habitat fragmentation and degradation. Concurrently, the area of naturally regenerated forest that is not classified as primary forest has declined. As a result of increasing management intensity, the area of unmanaged forest, typically defined as land lacking protected status or a management plan, dropped significantly since 1990 and now comprises only 21% of global forests. There have been significant increases in areas of forest used for non-wood forest products such as protection of soil and water, conservation of biodiversity, and provision of social services. Globally, timber production has been relatively stable since 1990, but increasing areas of forest used for non-wood forest products indicates that harvesting is taking place on a smaller proportion of the total forest area. Based on trends in the area of managed forest and regional studies, it is clear that historical and current forest management has been a very significant determining factor of current carbon stocks. Established forests currently offset about 30% of global emissions of CO 2 from fossil fuel use, and there are mitigation opportunities involving forests that could increase the gross terrestrial C uptake from roughly 4.0 to 6.2 Pg C annually. However, our results suggest that a diversifying use of forest land may have significant consequences for maintaining or increasing the current rate of terrestrial carbon sequestration. In the future, indirect human influences such as increasing atmospheric CO 2 and climate change, along with the direct effects of land management and projected increasing demand for wood biofuel, are likely to become increasingly important elements that influence land management strategies and the role of forests in the global carbon cycle. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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6. Activity-specific evaluation of winter habitat use by Japanese macaques in snow areas, northern Japan: Implications for conifer plantation management.
- Author
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Sakamaki, Haruka and Enari, Hiroto
- Subjects
HABITATS ,MACAQUES ,UNDERSTORY plants ,CONIFERS ,PLANTATIONS ,FOREST management ,SNOW cover ,FOREST ecology - Abstract
Abstract: Monocultural conifer plantations are often recognized as low quality habitats for most mammals, owing to the scarcity of understory plants. This paper presents a multifaceted assessment of conifer plantations as habitats of Japanese macaques (Macaca fuscata) inhabiting an area of heavy snow cover in northern Japan. We evaluated habitat use by two macaque troops in cool-temperate forests, including conifer plantations, which are located in the Shirakami Mountains. Habitat use was classified into three behavioral categories; feeding, resting, and traveling. We directly observed two radio-tagged troops by using the scan sampling technique throughout the day during winter, which is the main bottleneck season in terms of food availability. At each sampling event, we recorded the location of different troops and the behavioral patterns of individuals. We then constructed suitability models for each of the three types of habitat use, by using ecological-niche factor analysis (ENFA) with 12 environmental variables. The ENFA results showed that macaques avoid old conifer plantations, but use young conifer plantations for all behavioral categories, especially as feeding sites. However, the suitability models indicated that geographic features have a larger influence on macaque habitat use than forest cover type. In fact, the feeding, resting, and traveling sites were concentrated on the southern slopes of near the roads at low altitudes. Our findings provided a reasonable indication that macaque habitat use during the snowy season has greater sensitivity to microclimate, such as the amount of sunlight and air temperature, compared to other environmental conditions (e.g., the distribution of food resources). In light of this finding, we suggest that standard timber production does not necessarily directly compete with the conservation of macaque habitats. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
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7. Modern forest management and the decline of the Woodland Brown (Lopinga achine) in Central Europe.
- Author
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Streitberger, Merle, Hermann, Gabriel, Kraus, Wolfgang, and Fartmann, Thomas
- Subjects
FOREST management ,NYMPHALIDAE ,KEYSTONE species ,FORESTS & forestry ,BIOAVAILABILITY ,HOST plants ,HABITATS - Abstract
Abstract: The Woodland Brown (Lopinga achine) is a characteristic flagship species for forests. Although it has experienced a dramatic decline, our knowledge concerning the reasons for the population loss is scarce. In this paper: (i) we analyze its habitat preferences on a regional scale in the Bavarian Alps; and (ii) we attempt to determine potential drivers of the decline on a national scale across Germany. Vegetation structure, microclimate and host-plant availability were the most crucial factors explaining habitat selection. Forests with a light canopy on south-facing slopes were the preferred woodland type in the study area. They had a medium-high and dense herbaceous layer rich in low-competitive sedges. Carex alba appeared to be the main host plant. Dense stands of C. alba are necessary to fulfill the eggs’ humidity requirements and to enable ease of access by the larvae. The preference for extraordinarily light forests on warm south-facing slopes most likely reflects a compensation for the cold mountain climate near the altitudinal range limit. Within Germany, L. achine populations have become extinct in regions with a mild climate, while most of the remaining colonies are restricted to areas with cold winters. However, the explanatory power of the model was very low. As the disappearance of the species coincides temporally with the abandonment of coppicing and wood pasture, we assume that the cessation of this management technique was the major driver of the range retraction. In most of the Central European habitats, long-term survival of L. achine strongly depends on suitable forest management. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
8. Environmental diagnosis: Integrating biodiversity conservation in management of Natura 2000 forest spaces.
- Author
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Velázquez, Javier, Tejera, Rosario, Hernando, Ana, and Victoria Núñez, María
- Subjects
BIODIVERSITY ,NATURE conservation ,HABITATS ,PLANT diversity ,BOTANY ,FOREST animals ,METHODOLOGY ,VEGETATION & climate - Abstract
Abstract: The conservation of biodiversity in Europe is defined by Directive 92/43/EEC – commonly known as the Habitats Directive – relating to the conservation of natural habitats and of wild flora and fauna. This Directive established the creation of an ecological network of European protected areas – the Natura 2000 network – , and also recognised the need to manage these areas to maintain their “favourable conservation status”. This paper proposes a methodology which enables the conservation of biodiversity to be integrated into the management of Natura 2000 forest spaces. The methodology comprises an “environmental diagnosis” in three phases. The first phase evaluates the current conservation status of habitats using the following criteria: vital functions; floristic richness; forest structure; area occupied by the habitat; and recovery capacity. The second phase assesses the fragility of the space to determine the degree of vulnerability of habitats. This involves evaluating the fire hazard, erosion hazard, and the fragility of the vegetation. The last phase combines the two previous ones to generate management areas (optimum, intermediate or unfavourable) and to prioritise management actions. This methodology was applied in a protected forest area in the Natura 2000 network, located in Avila (Spain). Different management areas were generated for biodiversity conservation, and each habitat was associated to one of them. Finally, actions were prioritised and designed to raise the habitats to a “favourable conservation status”. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
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9. Landscape metrics and topographical determinants of large-scale forest dynamics in a Mediterranean landscape.
- Author
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Geri, Francesco, Rocchini, Duccio, and Chiarucci, Alessandro
- Subjects
FOREST dynamics ,LANDSCAPE ecology ,LAND use ,HABITATS ,PLANT species ,FOREST mapping ,AFFORESTATION - Abstract
Abstract: The analysis of land-use and land-cover change has long been a key topic in Landscape Ecology. In particular, forest fragmentation is known to affect species composition and diversity, thus threatening the integrity of forest habitats. This paper examines the forest cover dynamics in a Mediterranean area (the Province of Siena, central Italy), by comparing historical (1933) and recent forest maps (2000). The historical map has been geo-referenced, digitised in a GIS environment, and classified in three forest classes: broad-leaved, conifer and mixed forests. The same classification was used for the recent forest map. Image processing techniques and landscape pattern metrics were applied to quantify the changes in forest cover patterns, while appropriate statistical descriptors were adopted to investigate the relationship between land-cover changes and topographical factors. A general afforestation process was detected in the investigated area over the period 1933–2000, resulting in a high landscape transformation overall considering zones with higher elevation and slope. The forest landscape structure changed in terms of decreased fragmentation and patchiness. The general trend observed in this area was in line with previous results achieved in similar ecological situations, thus reinforcing the need to link landscape change patterns with appropriate management decisions. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
10. Indicators of sustainable forestry: The association between wildlife species and forest structure in Finland
- Author
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Vierikko, Kati, Pellikka, Jani, Hanski, Ilpo K., Myllyviita, Tanja, Niemelä, Jari, Vehkamäki, Seppo, and Lindén, Harto
- Subjects
- *
BIOINDICATORS , *SUSTAINABLE forestry , *SPECIES diversity , *HABITATS , *FOREST management , *COMMERCIAL forests , *LAND use , *DECISION making - Abstract
Abstract: There is a long tradition of sustainable forest policy in Finland. Today, forests should be managed on the basis of the principles of sustainable forestry. However, economics have driven such forestry practices, resulting in dramatic changes to the natural structure and dynamics of Finnish forests. Commercial forests should, however, also provide habitats for various organisms, and forestry activities should not reduce forest biodiversity. Indicators can provide useful information on the ecological status and trends in sustainable forestry, such information can then be used by decision-makers. In attempts to develop accurate and reliable indicators, it has been suggested that statistical data, inventory data and data on many taxa may prove useful. The richness of game species and the abundance of the Siberian flying squirrel have been considered as candidate indicators for sustainable forestry. Indicators of sustainable forestry are commonly used separately and the interrelations between the ecological, economic and social dimensions of forestry have rarely been studied. In this paper we examine associations between the abundance of animal species (16 game species and Siberian flying squirrels) and their co-occurrence with forest structural characteristics that are considered to be indicators of sustainable forestry. We were also interested in examining regional patterns of the variables, and determining which socio-economic indicators and land-use factors were associated (positively or negatively) with areas of forest for which there were indicators suggesting a good ecological condition. The study area consisted of 39 observation units. Based on our exploratory and descriptive analyses we suggest that using indices for different wildlife species groups and relative abundances of the Siberian flying squirrel together with forest structural characteristics and adequate socio-cultural variables could provide relevant information about trends in sustainable forestry. The application of indicators always depends on socio-cultural contexts and biogeographical factors, and these must be taken into consideration when making predictions or comparing different regions. [Copyright &y& Elsevier]
- Published
- 2010
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11. Designing old forest for the future: Old trees as habitat for birds in forests of Mountain Ash Eucalyptus regnans.
- Author
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Loyn, Richard H. and Kennedy, Simon J.
- Subjects
OLD growth forests ,HABITATS ,FOREST birds ,EUCALYPTUS regnans ,STRATEGIC planning ,FOREST management ,BIODIVERSITY conservation ,WILDFIRES - Abstract
Abstract: Old trees are one of many habitat attributes associated with old forests. They are known to be required by many wildlife species including cavity-dependent birds. Forest managers need to select strategies for retaining and regrowing old trees to maintain suitable numbers over time at appropriate configurations in the forest landscape. This paper presents data from wet forests in south-eastern Australia to help elucidate the effects of different strategies on forest birds as one element of biodiversity that needs to be conserved in these forests. Bird abundance was assessed by standard area search at 117 sites in forests of Mountain Ash Eucalyptus regnans in the Victorian Central Highlands, over the course of two spring-summer breeding seasons from 1996 to 1998. The sites contained 60-year regrowth from extensive wildfires in 1939, along with varying numbers of older trees that had survived the fire. Some of the old trees were dead and at varying stages of decay. Numbers of old trees were counted at each site and a range of other habitat measurements taken. Birds were considered by species or guilds of species (feeding and nesting guilds). Bird abundance data were regressed against numbers of old trees and other relevant habitat data. Cavity-nesting birds were positively related to numbers of old trees, and especially to those that remained alive. Bird species that nest in longitudinal cavities in small branches (spouts) were rare at sites that lacked old trees, and were related strongly to numbers of live old trees. Large cavity-nesters were related to numbers of live old trees or all old trees. Treecreepers correlated less strongly, perhaps because they use cavities in decaying snags and stumps as well as large old trees. Honeyeaters and Mistletoe birds were also positively associated with numbers of live old trees, although they do not need cavities. Total bird abundance was positively related to live, dead or all old trees. Several other relationships were found. For example, shrub foragers were related positively to abundance of tall shrubs but not low shrubs; wattle foragers were related positively to abundance of wattles (especially Silver Wattles Acacia dealbata); and Eastern Spinebills Acanthorhynchus tenuirostris were positively associated with abundance of Mountain Correa Correa lawrenciana (the flowers of which provide a major source of nectar). Non-linear relationships between bird abundance and densities of old trees were found for at least two cavity-nesting bird species. The relationship was convex for Striated Pardalote Pardalotus striatus (optimum density 5–12 live old trees/ha) and mildly concave for Crimson Rosella Platycercus elegans. This suggests that the former would benefit from strategies to disperse old trees among regrowth at suitable scales whereas the latter would benefit from strategies to produce clumped distributions of old trees. However, Striated Pardalotes showed a strong preference for live old trees, which cannot easily be kept alive among regrowth after logging or fire, suggesting clumped retention may be more practical for that species too. Three other species showed weak evidence of non-linear responses, but most species showed no significant evidence of departure from linearity. No species or guild showed strong evidence of a threshold level of old tree density (above ∼1ha
−1 ) below which those birds would not occur. Hence for most of the diurnal birds considered in this study, old trees appear to be useful in proportion to the overall number of suitable old trees that can be retained and regrown (rather than their spatial pattern), and especially the number that can be kept alive. Clumped retention strategies give the best chance of keeping many retained trees alive in retained patches. Otherwise, spacing patterns should be a secondary consideration, except where they are known to be important for species such as owls and arboreal mammals. [Copyright &y& Elsevier]- Published
- 2009
- Full Text
- View/download PDF
12. Snow avalanche disturbances in forest ecosystems—State of research and implications for management.
- Author
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Bebi, Peter, Kulakowski, Dominik, and Rixen, Christian
- Subjects
FORESTS & forestry ,AVALANCHES ,FOREST ecology ,FOREST management ,EFFECT of environment on plants ,MOUNTAIN ecology ,ECOLOGICAL disturbances ,HABITATS ,FOREST biodiversity ,SNOW protection - Abstract
Abstract: Avalanche disturbances are important processes in many subalpine forest ecosystems but have received relatively little research attention in comparison to other major types of disturbances. This paper presents a review of interactions between forests and snow avalanches in mountain ecosystems and discusses how avalanche disturbance regimes and associated management may change in the future. Avalanche disturbance regimes are two-way interactions in which forest structure and composition affect avalanches and avalanches, in turn, affect structure and composition. Avalanches can damage or kill individual trees over 10–100s of hectares in forests that are located in vulnerable topographic settings. At a stand scale, avalanche disturbances typically result in forest communities that are characterized by smaller and shorter trees, shade intolerant species, lower stem densities, and greater structural diversity compared to many unaffected subalpine forests. These disturbed communities often provide unique habitats for various animal and plant species and can contribute to overall higher alpha and beta biodiversity. At a broader scale, avalanche tracks provide increased landscape heterogeneity and edge density and can serve as firebreaks. Conversely, forests can affect the likelihood of avalanches starting and can thus protect large areas of human settlement and infrastructure. Forests generally reduce the likelihood of avalanche disturbances in mountain environments, but the degree to which forests serve this function varies with stand structure. Forest conditions that reduce likelihood of avalanche releases include a crown coverage of >30%, the absence of gaps >25m in length, and an increased terrain roughness associated with lying or standing trees that exceed snow-depth. Future changes in climate and land-use are likely to impact forest cover and composition as well as snow avalanche disturbances. This is likely to alter the location of areas where avalanches play an important role in stand dynamics. Current knowledge on avalanche–forest disturbances provides a useful basis for managing avalanche prone forests based on cost-efficiency considerations. However, further research is needed to address uncertainties in the current knowledge of avalanche disturbances, the likely interacting effects of changes in climate and land-use on avalanche regimes, potential future shifts of avalanche prone areas, and the impacts of avalanches on biodiversity and other ecosystem services. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
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13. Models of tree-level hollow incidence in Victorian State forests.
- Author
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Fox, Julian C., Hamilton, Fiona, and Ades, Peter K.
- Subjects
FOREST reserves ,HABITATS ,FOREST products ,TREES - Abstract
Abstract: This paper details predictive models of tree-level hollow incidence for State forests in central and eastern Victoria. Models are based on the hollows component of the Statewide Forest Resource Inventory (SFRI), the most comprehensive database of hollow incidence in Australia. A two-stage methodology was used at the individual tree-level that in its first-stage generated a statement of the probability of hollows presence, and in its second-stage estimated the size of hollows. The hierarchical nature of SFRI data prompted the search for statistical methodology capable of explicitly modelling a complicated error structure. Subsequently, generalised linear mixed models (GLMMs) were used to estimate first-stage, tree-level models in the presence of spatial and nested dependence. The developed models were statistically and biologically plausible and performed well when validated using independent data. By overcoming the limitations facing previous research associated with insufficient data and inappropriate statistical methodology viable predictive models were developed. Tree-level models will help us understand patterns of hollow incidence, can be used for predictive purposes when individual-tree information is available, and can improve habitat tree retention guidelines. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
14. A method for evaluating alternative landscape management scenarios in relation to the biodiversity conservation of habitats
- Author
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Haddock, Janet, Tzanopoulos, Joseph, Mitchley, Jonathan, and Fraser, Rob
- Subjects
- *
FOREST management , *LANDSCAPE protection , *LAND use , *BIODIVERSITY , *HABITATS - Abstract
Abstract: A perennial issue for land use policy is the evaluation of landscape biodiversity and the associated cost effectiveness of any biodiversity conservation policy actions. Based on the CUA methodology as applied to species conservation, this paper develops a methodology for evaluating the impact on habitats of alternative landscape management scenarios. The method incorporates three dimensions of habitats, quantity change, quality change and relative scarcity, and is illustrated in relation to the alternative landscape management scenarios for the Scottish Highlands (Cairngorms) study area of the BioScene project. The results demonstrate the value of the method for evaluating biodiversity conservation policies through their impact on habitats. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
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