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The maximum entropy (MaxEnt) method has gained widespread use for distribution modelling, mostly because of the practical simplicity offered by the maxent.jar software. Whilst MaxEnt was originally described as a machine learning method, recent studies have shown that the method can be explained in terms of maximum likelihood estimation. This opens for using MaxEnt with new settings and options, such as new model selection and model assessment criteria, and improved user control of the variable selection process. New practical tools are needed to explore the new opportunities and assess if they enhance model performance and ecological interpretability of the models. We present a new conceptual framework, the Modular and functionally Integrated component-based Approach (MIA) framework for practical distribution modelling by which the core components of the DM process are decoupled and then wrapped together more flexibly into component-based functional modules. Computational object-oriented and workflow approaches are integrated with ecological, statistical and modelling theory in order to handle the complexity associated with the full modelling process in a practical way. Objects (variables, functions, results, etc.) are defined according to specific modelling parameters. Properties (e.g., identities and content) are inherited between objects and new objects are created in a flexible and automated, yet traceable way. We operationalise this framework for MaxEnt by the MIA Toolbox (MIAT), a set of flexible, modular R-scripts (available in supplementary appendices) wrapped around maxent.jar and existing R-functions. MIAT covers the full range of options and settings for the maximum likelihood implementation of MaxEnt and provide flexible guidance of users through the DM process. A trail of models of increasing complexity is built to enhance traceability and interpretability, and to suit different modelling purposes. We briefly outline research questions that can be addressed by the MIAT. [ABSTRACT FROM AUTHOR]

The effect of air pollution from the Petchenganickel industrial complex, northwestern part of the Kola Peninsula, on forest vegetation was studied by combining three dormant monitoring networks in Finland, Russia and Norway, comprising a total of 21 plots that were revisited in 2004. Chemical composition of precipitation was monitored during 2004-2005, and indicated continuing high deposition of heavy metals and SO2 in the border area. The cover of epiphytic lichens on the trunks of downy birch (Betula pubescens) and Scots pine (Pinus sylvestris) was severely affected by pollution, and there was also a consistent negative effect on the abundance and richness of lichens and bryophytes on the forest floor in a more limited area. The effects of pollution on crown condition and stand growth were weak or absent. This study is an important reference for evaluating the effects of the planned renovation of the smelter in Nikel. [ABSTRACT FROM AUTHOR]

Value assessment is a central element in an EIA for the understanding of the impacts of specified projects. The value assessment contains subjective elements and this may cause errors and difficulties in numeric value assessment methods. There is a need for transparent common criteria to promote discussion and understanding. A common criteria base already exists, but lack of communication between different management systems and different disciplines, all with different traditions in value assessment, makes the situation complex. In this article we have looked into the basic understanding of value linked to the investigation themes of natural environment, cultural heritage and society. The investigation themes linked to social science is difficult to incorporate into a common system, basically because they have less focus on land use and contain different value types. Much of the relevant literature about value assessment is linked to the assessment of sites of special interest as candidates for legal protection or conservation. In an EIA a much broader range of areas is introduced, including the “every day landscape” with a lower and more general level of value. Together with a focus on mitigation and adjustments of plans, this results in a need for a more detailed value assessment scale than is normally in use today. We have suggested a new scale to ease communication between different disciplines and management systems. How we understand value is not constant over time, nor is the level of knowledge. This makes it necessary to sustain an ongoing debate on value assessment. The need for a dynamic value assessment system increases with the increasing use of database modelling, digital analysis of map data (GIS) etc. Lack of a ongoing value debate will rapidly lead to misleading and biased results. [Copyright &y& Elsevier]

The Norwegian-Russian border area is exposed to air pollution from Russian nickel-copper smelters at Kola Peninsula. An attempt was made to relate distribution and abundance of epiphytic lichens to concentrations of sulphur, nickel and copper in birch and bilberry foliage and soil. Lichen cover showed significant correlation with Ni and Cu concentrations. However, since the deposition patterns of airborne heavy metals and sulphur dioxide (SO2) around the smelters differ, some plots experience low lichen cover, despite low heavy metal concentrations. These plots are affected by relatively high SO2 emissions. Climatic variability within the study area may also play a role in explaining variation in lichen cover. For areas with uniform climate and physiognomy nearer than ca. 20 km from the smelters, Ni concentrations in birch leaves may prove useful for estimating the likelihood for recolonization to take place. The area closest to the smelters presently is much too polluted for lichen recolonization to occur. [ABSTRACT FROM AUTHOR]

The overall quality of the landscape is important for conserving biodiversity. In a fragmented landscape, movement and dispersal capacity are important factors in determining which species are able to persist. To examine the role of landscape structure and pattern on movement, we developed a simple model to predict the “least-cost” pathway a species would take through an agricultural landscape matrix between habitat fragments by assigning friction values to different habitat types. Our model was validated by using empirical data on inter-patch movement for two butterfly species. As a measure of the ecological distance between habitat patches, the least-cost path model was a better predictor of butterfly movement than Euclidean distance. Ranking several hypothetical management scenarios, illustrated the potential of the model as a decision-support tool. Removal of all infrastructure from within arable fields would significantly reduce rates of inter-patch movement. However, if all boundaries between arable fields were restored to grassy banks this would significantly increase the connectivity between sub-populations. Planners widely recommend using corridors to connect fragments of remnant habitat despite relatively little empirical evidence to show that dispersal of individuals is enhanced by this practice. Our model showed that important aspects of species movement and, hence, survival can be expressed in models suitable for area planning and management. [Copyright &y& Elsevier]

Assessing cumulative effects are a vital task for strategic environmental assessments (SEA) but lack of consistent methodology has hampered the development and implementation of useful tools. We present a model for GIS and multivariate analysis to assess the effects on a valued ecosystem type at a regional scale based on the sum of impacts of local projects. We demonstrate application of the model by assessing how hydropower developments would generate cumulative impacts on river gorges for a county in northern Norway. We use principal component analyses (PCA) of spatially-explicit variables from the region to describe the diversity of river gorge ecology with a mathematical low-dimensional bioclimatic space. We then calculate cumulative effects of hydropower development as the proportions of subspaces of the multidimensional bioclimatic PCA that are affected by either existing infrastructure or planned and possible hydropower developments. The results showed that adding development of all potential sites for small-scale hydropower would have substantial impacts on over half of all bioclimatic segments where gorges were registered and more than 70% of all segments with forested river gorges. By demonstrating these possible cumulative effects we can illustrate the need for caution in hydropower planning to avoid reducing river gorge representativeness and diversity. The method can be applied for other types of development projects and other valued ecosystems, provided the assessed ecosystems and development installations can be mapped or modelled over a sufficiently large area. Unlabelled Image • Modelling valued ecosystem components (VECs). • Dividing a multidimensional bioclimatic PCA in segments used for measuring representativeness. • GIS overlays to measure the degree of possible erosion of representativeness. [ABSTRACT FROM AUTHOR]