BSEP116B Biodiversity in the Baltic Sea - Helcom

Mussel bed reef community, Jasmund, Germany
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was fixed at 50% from the reference value, which
also was used if no other acceptable deviation was
specified by the case study authors.
The BEAT matrix divides the range of possible
values into five classes: high, good, moderate,
poor, and bad. In this system, ’high’ and ’good’
are essentially equivalent to ’favourable conservation
status’ (~ ‘good environmental status’) and
’moderate’, ’poor’, and ’bad’ are equivalent to
’unfavourable conservation status’ (~ impaired
status). For technical details of the assessment
approach and definitions used for these five
classes, see Box 5.1.
In order to create an overall assessment of the site,
the reported indicators were regrouped in the following
categories: Category I - Landscapes, Category
II – Communities, and Category III – Species,
following the structure agreed in the HELCOM
BSAP. In addition to these three categories, an
additional Category IV for supportive features was
included to cover other parameters of interest (e.g.,
nutrient concentrations, physical variables). The
topics covered under each of these categories are
presented in Table 5.2. Within the Categories I–IV,
weighted averages of the ratios between pristine
and present status, or Ecological Quality Ratios
(EQRs), as well as the acceptable deviations of the
individual indicators were calculated. If not specified
otherwise, the weighting was kept neutral
by giving each of the indicators an equal weight.
On the basis of the EQR and AcDev values, the
Categories I–IV were each given a quantitative
assessment according to the principles described
above for a single indicator (ranging from high to
bad status).
The overall assessment of the site or geographic
unit, combining the results of the four categories,
is conducted by applying the so-called ‘One
out - All out’ principle to the Categories I–III. This
implies that the worst-performing category of
these three defines the overall status of the site.