BSEP116B Biodiversity in the Baltic Sea - Helcom

Box 1.1. Biodiversity
The term biodiversity is simply a short version of the two
words ‘biological diversity’, coined by Edward O. Wilson
in the 1980s. The concept embraces not only the variety
of living organisms but also the genetic diversity within a
species, as well as the diversity of habitats and landscapes.
The formal definition given by the Convention on Biological
Diversity is that “Biological diversity means the variability
among living organisms from all sources including, inter alia,
terrestrial, marine and other aquatic ecosystems and the ecological
complexes of which they are part; this includes diversity
within species, between species and of ecosystems”.
It should be noted that the term biodiversity can be used
in widely different contexts and with different meanings.
In a management context, as in this report, the abstract
term ‘biodiversity’ is used to reflect the ‘health’ of the
ecosystem, rather than the absolute diversity. The aim
is also to depict the concept in more concrete terms by
using specific time series or indicators. In this context,
links between biodiversity status indicators and human
pressures or activities are also described to point out the
anthropogenic activities whose regulation is the key to
preserving biodiversity.
The report also includes a special assessment of
the network of Baltic Sea Protected Areas (BSPAs)
(Chapter 7). The BSPA network is a central tool
for protecting Baltic Sea biodiversity and is essential
from the point of view of nature conservation.
In addition, one of the targets of the BSAP is to
have, by 2010, an ecologically coherent and wellmanaged
network of BSPAs.
The synthesis (Chapter 8) discusses challenges
and opportunities for improving biodiversity protection
in the future.
Process of producing the assessment
This assessment is based on existing knowledge
and the chapters cover different types of components:
qualitative descriptions, assessments based
on time-series analyses, whenever applicable, and
a pilot application of an indicator-based assessment
tool, the HELCOM Biodiversity Assessment
Tool (BEAT).
the Baltic Sea (HELCOM EUTRO-PRO). Together,
the time-series and the BEAT analyses were used
to evaluate the overall status of biodiversity and
nature conservation in the Baltic Sea.
1.2 A brief look at the history
of the Baltic Sea and its
biodiversity
The Baltic Sea has a long history of changing
salinity conditions, with both marine and freshwater
phases. This is clearly visible in fossil records,
which show an alternating dominance by typical
freshwater and marine species since the last glaciation
period (Berglund et al. 2005). The Baltic Sea
with salinity levels and climate conditions close
to the current conditions has existed for about
3000 years. In terms of ecological history, this is a
short period and the Baltic Sea still offers ecological
niches available for immigration (Bonsdorff
2006).
10
The time-series analyses are based on data submitted
by the national contact points of HELCOM
countries in a HELCOM BIO project that was
carried out to produce the assessment, as well
as data submitted directly by associated experts.
The BEAT case studies, presented in Chapter
5, are based on a compilation of records gathered
through the HELCOM BIO project and the
HELCOM project on the elaboration of an integrated
thematic assessment of eutrophication in
The Baltic Sea is still a highly dynamic system.
During the past one hundred years, the system
has undergone decadal variations in salinity,
oxygen and temperature (Winsor et al. 2001).
Changes in the abundance and distribution of
pelagic and littoral species and communities in
the Baltic Sea have been linked to these climatedriven
variations in hydrography (Alheit et al.
2005).