Geography Reference
In-Depth Information
9
Geosalar: Innovative Remote
Sensing Methods for Spatially
Continuous Mapping of Fluvial
Habitat at Riverscape Scale
Normand Bergeron
1
and Patrice E. Carbonneau
2
1
Institut National de Recherche Scientifique, Centre Eau Terre et
Environnement, Quebec, Canada
2
Department of Geography, Durham University, Science site,
Durham, UK
most-often face issues caused by large-scale anthro-
pogenic disturbances of the habitat, the scientific informa-
tion on which theymust base their management decisions
arises mainly from studies conducted over relatively short
(50-500m) and spatially discontinuous river segments
(Fausch et al., 2002). Because of their small spatial extent,
such studies cannot easily account for the important
effects of habitat heterogeneity and spatial organisation
of habitat patches on fish distribution and abundance. In
his dynamic landscape model of stream fish population
ecology and life history, Schlosser (1991) emphasised the
role of habitat heterogeneity in providing the various
types of habitat required by fish at different life stages for
spawning, feeding and finding refugia from harsh envi-
ronmental conditions. Because such a variety of habitat
type can only be found on stream segments that are rela-
tively long, studies conducted on a small-scale invariably
fail to include in their analysis all habitat components that
fish need to access in order to complete their life history.
Fausch et al. (2002) also argued that studying several
short sample sections distributed along a river only pro-
vided a fragmented viewof the riverscape evenwhenbased
9.1 Introduction
In 2002, a multidisciplinary group of researchers (biol-
ogists, geomorphologists, engineers) member of CIRSA
(Centre Interuniversitaire de Recherche sur le Saumon
Atlantique) initiated the Geosalar project. The aim of this
research initiative funded by the GEOIDE Network Cen-
tres of Excellence Program(http://www.geoide.ulaval.ca/)
was to develop and apply geomatics technology to the
problem of modelling Atlantic salmon (
Salmo salar
)pro-
duction in relation to fluvial habitat characteristics.
In the spirit of the riverscape approach fostered by
Fausch et al. (2002), the project proposed to develop
the tools needed to increase the scope (extent of studied
area/resolution) and spatial continuity of fish/habitat rela-
tionship investigations. In their landmark paper, Fausch
et al. (2002) demonstrated that the research commu-
nity had so far failed to provide river managers with
information and tools at the scale needed to efficiently
conserve stream fish populations, and they suggested
that this gap contributed to the constant decline of
many fish populations. Indeed, while stream managers
Search WWH ::
Custom Search