The aim of this overview paper is to analyze the use of various landscape metrics and landscape indices for the characterization of landscape structure and various processes at both landscape and ecosystem level. We analyzed the appearance of the terms landscape metrics/indexes/indices in combination with seven main categories in the field of landscape ecology (1) use/selection and misuse of metrics, 2) biodiversity and habitat analysis; 3) water quality; 4) evaluation of the landscape pattern and its change; 5) urban landscape pattern, road network; 6) aesthetics of landscape; 7) management, planning and monitoring) in the titles, abstracts and/or key words of research papers published in international peer-reviewed scientific journals indexed by the Institute of Science Information (ISI) Web of Science (WoS) from 1994 to October 2008. Most of the landscape metrics and indices are used concerning biodiversity and habitat analysis, and also the evaluation of landscape pattern and its change (up to 25 articles per year). There are only a few articles on the relationships of landscape metrics/indices/indexes to social aspects and landscape perception.

https://biblio.ugent.be/publication/695518/file/6820513.pdf

Landscape Metrics and Indices: An Overview of Their Use in Landscape Research

https://web.unbc.ca/~johnsoch/Publications/Wheatley%20and%20Johnson%202009%20Factors%20limiting%20our%20understanding%20of%20ecological%20scale.pdf

Factors limiting our understanding of ecological scale

Despite the clear importance of conserving biodiversity in urbanized areas, research on how bats are influenced by urbanization has is only recently catching up to the more established body of research for urban birds. Much of the extant research has been limited to urban parks and other natural areas. Here I present the results of an acoustic survey of bats throughout the agricultural/forest/suburban/urban mosaic of the Minneapolis-St. Paul metropolitan area. Activity indices by each of the six recorded species (Eptesicus fuscus, Lasiurus cinereus, Lasiurus borealis, Lasionycteris noctivagans, Myotis sp., and Perimyotis subflavus) were used as response variables with land cover variables in a series of statistical models. Because bats may perceive the landscape at different scales, candidate models included land cover variables within 100, 500 and 1,000 m of the sampling location. Activity of L. noctivagans was negatively related to the amount of impervious surface and open habitat in the immediate landscape. L. borealis activity was positively correlated with immediate tree cover and with impervious surface at the 1,000 m scale. Tree cover and proximity to water were positively related to activity levels of Myotis sp., L. cinereus and P. subflavus, but only the latter was influenced by the amount of surrounding impervious surface. These results suggest that a one-size fits all approach to bat conservation in human modified landscapes is not appropriate, but also that certain species appear to do well in urban environments provided that there is sufficient tree cover.

Relationship between land cover and insectivorous bat activity in an urban landscape

Forests are one of the most important habitats for insectivorous bats as they offer the potential for both roosting and foraging. We reviewed silvicultural literature from North America, Australia, and Europe and found that diverse research approaches have revealed commonalities in bat responses to forest silviculture. Almost all silvicultural treatments evaluated were compatible with some use by forest bats, though different bat ensembles respond in different ways. Ensemble ecomorphology was a consistent predictor of how bats respond to vegetative clutter and its dynamic changes as forests regenerate and develop a dense structure following harvesting. Sustaining high levels of bat diversity in timber production forests requires a mix of silvicultural treatments and exclusion areas staggered across the landscape, regardless of forest type or geographic region. Use of edge habitats, exclusion areas/set-asides, and riparian corridors for roosting and foraging by bats were consistent themes in the literature reviewed, and these habitat elements need to be considered in forest planning. Densities of hollow or dead trees sufficient to support large populations of roosting bats are unknown and remain a major knowledge gap, but will likely be species contingent. New paradigm shifts in forest management away from the use of even-aged systems to multi-spatial scale retention of mature forest including trees with cavities should be beneficial to bats, which are influenced by landscape-scale management. Such an approach is already in use in some regions, though there is a limited guidance on what constitutes a reasonable landscape threshold for retention. The effectiveness of such an approach will require long-term monitoring and research, especially with population studies which are currently lacking.

/pdf/insectivorous-bats-and-silviculture-balancing-timber-538ecwkecy.pdf

Insectivorous Bats and Silviculture: Balancing Timber Production and Bat Conservation

http://www.srs.fs.usda.gov/pubs/ja/ja_okeefe001.pdf

Macrohabitat factors affect day roost selection by eastern red bats and eastern pipistrelles in the southern Appalachian Mountains, USA

Declining bat populations and increasing demands on forest resources have prompted researchers to investigate tree roost selection of forest bats. Few studies, however, have investigated different spatial scales and landscape pattern as criteria for selection of tree roosts. In 1999 and 2000, we radiotracked 23 eastern red bats (Lasiurus borealis) to 64 day roosts. Using univariate and multivariate comparisons, we tested roost tree variables with random tree data at 3 circular spatial scales: roost tree, plot, and landscape. We found 15 variables that were entered in a stepwise discriminant analysis to best differentiate between the roost and random samples; 11 (73.3%) were landscape variables measured with a geographic information system. On average (&#x1d465; ± SE), red bats roosted in deciduous trees (42.0 ± 2.1 cm dbh) that were located in plots with more (3.1 ± 0.1 m2) basal area, higher (84.0 ± 1.3) percentage of canopy closure, and lower (27.2 ± 2.2) percentage of groundcover than random plots. A...

Dixie L. Birch

Papers

Tree Selection and Landscape Analysis of Eastern Red Bat Day Roosts