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Assessment and monitoring of ecosystem health in the sea:
A description of the Swedish monitoring system for coastal
marine areas
G. Dave
Department of Applied Environmental
Science, University of Göteborg, P0. Box 464, SE 40530
Göteborg, Sweden.
E-mail: goran.dave@miljo.gu.se
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Abstract
Swedish coastal waters range in salinity from 0
psu (practical salinity units = o/oo) in the Bothnian Bay, which
is part of the Baltic Sea, to 35 psu in the Skagerrak, which belongs
to the North Sea and the Atlantic Ocean. Natural variations in ambient
conditions include weather and climate due to latitudinal, seasonal
and annual variations. Anthropogenic inputs of pollutants originate
from local point sources and diffuse and distant sources. These
inputs may cause local and regional as well as national and international
problems. Therefore, local and regional monitoring programs are
integrated into the Swedish national monitoring program, which is
also co-coordinated with other national and international monitoring
programs. The aim of this paper is to describe and assess the Swedish
monitoring system for the marine and coastal environment and to
discuss its strengths and weaknesses. The monitoring system incorporates
a combination of chemical-physical and biological parameters. Measured
parameters are accompanied with specific quality criteria. In most
cases the criteria are based on an estimate of a 'natural state'
and the appraisals are expressed on a scale of 1-5 (high, good,
fair, poor and bad quality). Three major threats to the marine environment
are eutrophication, toxic organic pollutants/metals and physical
disturbance (exploitation of the coast). The parameters used to
assess eutrophication are concentrations of nitrogen, phosphorus
and silica, Secchi depth, concentration of chlorophyll, benthic
fauna and macrovegetation. Metals and toxic organic pollutants are
assessed based on their concentrations in sediment and selected
organisms. The assessment of the degree of physical disturbance
of coasts and seas is based on the number of buildings along the
shoreline, physical disturbance along the shoreline, proportion
of exploited/disturbed coastal water zones and jetty length. Other
threats, which are also briefly discussed in this paper, are impact
from the fishery and the potential toxic impact of contaminants,
which are not being measured.
Keywords: eutrophication, fishery, marine, metals, monitoring,
physical disturbance, sea, toxic chemicals
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