HELCOM Pre-core indicator Cumulative impacts on benthic biotopes - - PowerPoint PPT Presentation

HELCOM Pre-core indicator

Cumulative impacts on benthic biotopes

Birgit Heyden, Torsten Berg, MariLim

presented by Juliane Wendt, IOW

Project results for the German Baltic Sea

Basics

• Indicator D6C3 MSFD
• Indicator of high priority to lead together by Germany and

Sweden (S&C 6-2017)

• ‘Cumulative impact on benthic biotopes’ indicator (CumI)

as long-term target , BSII as interim solution for HOLAS II purposes (S&C 5-2016)

• Indicator assessment evaluates multiple physical pressures
• n the seafloor (fishing, dredging, dumping, marine

constructions)

• Impacts are cumulative in terms of spatial and temporal
• verlaps

Method/assessment procedure

Frequency Intensity Pressure Impact Resilience Resistance Sensitivity

• Individual impacts derived from

specific pressures combined with sensitivities

• Final cumulative impact on

benthic biotopes derived by hierarchically intersecting individual impacts

Method/assessment procedure

• Biotope map as a basis, broad scale habitats level 3 as minimum

requirement

• Classification of pressure magnitudes and pressure specific

sensitivities for the different biotopes used (matrix 1 and 2)

• Transformation of pressures to impacts (matrix 3)
• Cumulation process by pairwise intersection (matrix 4)

Magnitude of pressure intersection matrix Frequency persistent (more than three times per year or permanent) frequent (two to three times per year) regular (once per year)

• ccasional

(less than once per year) Intensity high (0.75–1) High High Moderate Moderate moderate (0.5–0.75) High Moderate Moderate Low low (0.25–0.5) Moderate Moderate Low Very low very low (0–0.25) Moderate Low Very low Very low

1

Sensitivity intersection matrix resilience very low (> 10 years) low (5–10 years) moderate (1–5 years) high (<1 year) resistance very low High High Moderate Moderate low High Moderate Moderate Low moderate Moderate Moderate Low Very low high Moderate Low Low Very low

2

Impact intersection matrix Magnitude of pressure High Moderate Low Very low Sensitivity High High High Moderate Moderate Moderate High Moderate Moderate Low Low Moderate Moderate Low Very low Very low Moderate Low Very low Very low

3

Cumulation matrix Impact 2 Moderate Low Very low Impact 1 Moderate High Low High Low Very low Moderate Low Very low

4

Sensitivities + pressures = impact

Pressure specific sensitivities:

• Abrasion/penetration divided into surface and subsurface (fishery pressure)
• Smothering/siltation (dumping and dredging pressures)

German test case results

• Main impacts by fisheries besides dredging, dumping, extraction

and constructions

• In most cases areas of ‘very low’ and ‘low’ impacts correspond to

NATURA 2000 sites

Quantitative assessment

• Boundary between ‘low’ and ‘moderate’ cumulative

impacts defined as ‘significant impact’ or adversely affected

• Spatial extent of significantly impacted area less than 25 %
• f overall biotope area as basic proposal for good

environmental status (comparable to OSPAR BH 3 assessment)

• Development of numerical values or ratios in process
• further modifications needed for rare and threatened

biotopes (FFH, Red listed biotopes)

Outlook

• Assessment of cumulative impacts on different levels of

detailed data (broad scale habitats or biotopes HUB level 5/6 with corresponding sensitivities, variable number of pressures)

• Extension of test assessment area to include data of other

countries (validation of the assessment procedure)

• further modifications of pressure and sensitivity

classification in order to improve the assessment of the resulting magnitude of pressure depending on data availability

Thank you!

CumI - BSII

CumI:

• Main impacts by

fisheries besides dredging, dumping, extraction and constructions

BSII:

• Highest potential

impacts due to physical loss (extraction, constructions) and multiple pressures near the coast