Meny

Du är här

Ring-based versus disc-based separation of spatial scales: a case study on the impact of arable land proportions on invertebrates in freshwater streams

Författare:
Publiceringsår: 2011
Språk: Engelska
Sidor: 351-356
Publikation/Tidskrift/Serie: Aquatic Ecology
Volym: 45
Nummer: 3
Dokumenttyp: Artikel
Förlag: Springer Netherlands

Sammanfattning

The impact of different land-use types on
species is traditionally estimated by correlating
landscape proportions recorded in buffer areas around
focal points with species data observed at these sites.
If a high proportion of a specific land-use type exists
within a small radius, it will be accumulated in larger
buffers and may confound the interpretation at larger
scales. We sampled freshwater invertebrates in ten
streams using cages with artificial substrate and
compared the effects of arable land proportions
calculated in disc-shaped buffers of increasing radius
versus areas calculated from non-overlapping rings of
increasing radius. We hypothesize that (1) the
accumulative disc-based approach leads to confounding
effects across increasing buffer size and that (2)
the use of ring-based methods facilitates the identification
of relevant scales for conservation measures.
The abundance of crustaceans showed a positive
relationship with arable land proportions, but Plecoptera
abundance and the taxonomic richness of
Ephemeroptera and Plecoptera decreased with
increasing arable land proportions in the surrounding
landscape. Our results further support the presence of
confounding effects in disc-based analyses, as correlations
between arable land proportions and Crustacea,
or Plecoptera, respectively, were affected by the
accumulation of small-scale area proportions. The
distance at which arable land proportions significantly
affected benthic fauna in freshwater streams
was consistently shorter if calculated from rings
rather than from discs. Although an a priori definition
of ring width introduces new challenges, a combined
use of disc- and ring-based techniques for the
estimation of land-use effects may substantially
improve the realization of conservation and protection
measures in terrestrial and aquatic systems.

Disputation

Nyckelord

  • Biology and Life Sciences
  • Arthropod diversity
  • Crustacea
  • EPT taxa
  • Landscape analysis
  • Land-use type
  • Multi-scale analysis
  • Spatial analysis
  • Spatial memory

Övriga

Published
Yes
  • ISSN: 1386-2588 (Print)
  • ISSN: 1573-5125 (Online)

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu [dot] se

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen