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

HELCOM Pre-core indicator Cumulative impacts on benthic biotopes Project results for the German Baltic Sea Birgit Heyden, Torsten Berg, MariLim presented by Juliane Wendt, IOW

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 on the seafloor (fishing, dredging, dumping, marine constructions) • Impacts are cumulative in terms of spatial and temporal overlaps

Method/assessment procedure Resistance Frequency Impact Pressure Sensitivity Intensity Resilience • 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) 1 2 Frequency resilience Sensitivity Magnitude of very low low moderate high persistent frequent regular occasional intersection matrix pressure intersection (> 10 years) (5 – 10 years) (1 – 5 years) (<1 year) (more than three times (two to three times (once per year) (less than once per matrix per year or permanent) per year) year) very low High High Moderate Moderate resistance high High High Moderate Moderate low High Moderate Moderate Low (0.75 – 1) moderate Moderate Moderate Low Very low moderate Intensity High Moderate Moderate Low (0.5 – 0.75) high Moderate Low Low Very low low Moderate Moderate Low Very low (0.25 – 0.5) very low Moderate Low Very low Very low (0 – 0.25) 3 4 Magnitude of pressure Impact 2 Impact intersection Cumulation matrix matrix Moderate Low Very low High Moderate Low Very low Moderate High High High High Moderate Moderate Impact 1 Sensitivity Low High Low Moderate High Moderate Moderate Low Very low Moderate Low Very low Low Moderate Moderate Low Very low Very low Moderate Low Very low Very low

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 % of 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