Physical disturbance (HOLAS 2)
Short description
Pressure layer combines all human activities that cause physical disturbance or damage to seabed. For several human activity datasets, spatial extents were given (table below). Buffers with decreasing value rates were applied to represent the impact distance of physical disturbance. The following human activities were combined into the physical disturbance layer; - Cables (under construction, 1 km buffer) - Coastal defence and flood protection (under construction, 500 m buffer) - Deposit of dredged material (500 m buffer for points and areas) - Dredging (maintenance) (500 m buffer for points and areas) - Extraction of sand and gravel (500 m buffer) - Finfish mariculture (1 km buffer) - Fishing intensity 2011-2016 average (subsurface swept area ratio) - Furcellaria harvesting - Pipelines (0,3 km buffer) - Recreational boating and sports - Shellfish mariculture - Shipping density - Wind farms (under construction) (1 km buffer) - Wind farms (operational) (0,1 km buffer) The human activity data sets were first processed separately covering the whole Baltic Sea and then summed together. In this integration, some data layers were down-weighted to arrive at a balanced pressure layer, as described below. High pressure intensity and/or slow recovery (weighting factor 1): Coastal defence and flood protection, Deposit of dredged material, Dredging, Extraction of sand and gravel and Fishing intensity Moderate to high (Weighting factor 0,8): Pipelines and Shipping density Moderate (Weighting factor 0,6): Finfish mariculture, Shellfish mariculture and Wind farms (under construction) Low to moderate (Weighting factor 0,4): Cables Low (Weighting factor 0,2): Maerl and Furcellaria harvesting, Recreational boating and sports and Wind farms (operational) Harbours and marinas were left out from the physical disturbance pressure to avoid double counting due to their representation in the shipping density and recreational boating and sports data sets.
Point of contact
HELCOM Secretariat
data@helcom.fi
Spatial extent
['7.818737', '33.903834', '52.502121', '66.484464']
Type
dataset
Metadata information
Identifier
Keywords
Oceanographic geographical features ; GEMET - INSPIRE themes, version 1.0 ;

environmental damage ; environmental impact ; GEMET ;

MADS ; HOLAS2 ;

Resource provider(s)
HELCOM Secretariat
data@helcom.fi

Lineage
Data source: See separate fact sheet on human activities listed below Data quality: Gaps may occur due to lack of data from all the countries. Also, missing data values were given with 25% percentile of remaining values in a dataset which reduces the accuracy of the data. Attribute information: Index value, representing combined pressure from several human activities. Spatial coverage: Entire Baltic Sea. Fishing intensity data missing from RU. Spatial resolution: Original data as vectors, shipping density and recreational boating and sports as 1 x 1 km grid, fishing intensity as 0,05 x 0,05 c-square degree grid. Finally converted to 1 km x 1 km grid. Human activity; Spatial extent; Attenuation gradient; Data calculations Cables (construction); 1 km; with sharp decline after 0.5 km; Location of constructed cables, Normalised Coastal defence and flood protection (construction); 0.5 km; sharp decline; Normalised Deposit of dredged material; 0,5 km; sharp decline; Sum amount of deposited material (tonnes), log-transformed, normalised Dredging (maintenance); 0,5 km; sharp decline; Sum amount of dredged material (tonnes, m³), For missing values 25% percentile of existing information was given, all sites where no information about dredging type given, was considered as maintenance dredging, log-transformed, normalised Extraction of sand and gravel; 0,5 km; sharp decline; Average amount of extracted material (m³), For missing values 25% percentile of existing information was given, log-transformed, normalised Finfish mariculture; 1 km; linear decline; Average P load, For missing values 25% percentile of existing information was given, weighted with bed exposure, log-transformed, normalised, weighting factor 0,6 Fishing intensity; ; ;Average of seabed surface contacting gear fishing intensity 2011-2016 (subsurface swept area ratio), log-transformed, normalised Furcellaria harvesting; ; ;Amount/area of harvested material normalised Pipelines (operational); 0.3 km; linear decline; Normalized, multiplied (with 0.8) to represent 80% of maximum possible intensity Recreational boating and sports; ; ; Fuel usage range in a 1km x 1 km cell, log-transformed, normalised Shellfish mariculture;1 km; linear decline; Average production (kg), For missing values 25% percentile of existing information was given, log-transformed, normalised Shipping density; ; linear decline; Average of total shipping density in a 1km x 1 km cell, rescaled in relation to water depth, log-transformed, normalised Wind turbines (construction); 1 km; sharp decline after 0.5 km; Normalised Wind turbines (operational); 0.3 km; linear decline; Normalised