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Rapid assessment of historic, current and future habitat quality for biodiversity around UK Natura 2000 sites
- I. N. VOGIATZAKIS, M. T. STIRPE, S. RICKEBUSCH, M. J. METZGER, G. XU, M. D. A. ROUNSEVELL, R. BOMMARCO, S. G. POTTS
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- Journal:
- Environmental Conservation / Volume 42 / Issue 1 / March 2015
- Published online by Cambridge University Press:
- 28 April 2014, pp. 31-40
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- Article
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Changes in landscape composition and structure may impact the conservation and management of protected areas. Species that depend on specific habitats are at risk of extinction when these habitats are degraded or lost. Designing robust methods to evaluate landscape composition will assist decision- and policy-making in emerging landscapes. This paper describes a rapid assessment methodology aimed at evaluating land-cover quality for birds, plants, butterflies and bees around seven UK Natura 2000 sites. An expert panel assigned quality values to standard Coordination of Information on the Environment (CORINE) land-cover classes for each taxonomic group. Quality was assessed based on historical (1950, 1990), current (2000) and future (2030) land-cover data, the last projected using three alternative scenarios: a growth-applied strategy (GRAS), a business-as-might-be-usual (BAMBU) scenario, and sustainable European development goal (SEDG) scenario. A quantitative quality index weighted the area of each land-cover parcel with a taxa-specific quality measure. Land parcels with high quality for all taxonomic groups were evaluated for temporal changes in area, size and adjacency. For all sites and taxonomic groups, the rate of deterioration of land-cover quality was greater between 1950 and 1990 than current rates or as modelled using the alternative future scenarios (2000–2030). Model predictions indicated land-cover quality stabilized over time under the GRAS scenario, and was close to stable for the BAMBU scenario. The SEDG scenario suggested an ongoing loss of quality, though this was lower than the historical rate of c. 1% loss per decade. None of the future scenarios showed accelerated fragmentation, but rather increases in the area, adjacency and diversity of high quality land parcels in the landscape.
Star–Forming Galaxies and Large–Scale Structure (Poster paper)
- Edited by Isaac Shlosman, University of Kentucky
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- Book:
- Mass-Transfer Induced Activity in Galaxies
- Published online:
- 05 May 2010
- Print publication:
- 02 June 1994, pp 487-488
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Summary
ABSTRACT
From the preliminary analysis of a sample of ≃ 600 galaxies with bj ≤ 19.4, and spanning a redshift interval up to z ≃ 0.3, we deduce that star formation per unit luminosity, as indicated by the OII 3727 line equivalent width, is a function of galaxy luminosity (decreasing at increasing luminosities), redshift (increasing at increasing redshift, or, physically, look–back time) and environment.
INTRODUCTION
At the ESO 3.6m telescope at La Silla, we are currently performing a redshift survey of galaxies with bj ≤ 19.4, in a rectangular area ≃ 22° × 1° (plus a nearby area of ≃ 5° × 1°) in a region around the South Galactic Pole. Up to now we have acccumulated spectra for ≃ 2,000 galaxies over ≃ 70% of the area.
The distribution in distance of the survey galaxies exibits significative peaks above the expectation at D ≃ 180h-1 Mpc and D ≃ 300h-1 Mpc. These peaks correspond to large scale structures extending over a significant fraction of the strip.
A large fraction of galaxies (≃ 40%) shows the presence of one or more emission lines (OII λ3727, Hβ, OIII λλ4959,5007). These objects can be either spiral galaxies, where lines originate mostly from HII regions in the disks, or galaxies undergoing a significant burst of star formation. The observed peaks in the galaxy distribution are much less pronounced when only emission line galaxies are considered. This suggests that either spiral galaxies are less frequent in the densest regions, thus confirming a large scale validity of the well known morphology–density relation, or starburst phenomena in galaxies occur preferentially in low density environments, or both.