10.5061/DRYAD.GHX3FFBMQ
Jonsson, Per
0000-0002-1793-5473
University of Gothenburg
Hammar, Linus
Swedish Agency for Marine and Water Management
Wåhlström, Iréne
0000-0001-8735-268X
Swedish Meteorological and Hydrological Institute
Pålsson, Jonas
0000-0002-3134-4602
Swedish Agency for Marine and Water Management
Hume, Duncan
Geological Survey of Sweden
Almroth-Rosell, Elin
0000-0003-4052-045X
Swedish Meteorological and Hydrological Institute
Mattsson, Martin
Medins Havs och Vattenkonsulter AB
Combining seascape connectivity with cumulative impact assessment in
support of ecosystem-based marine spatial planning
Dryad
dataset
2020
FOS: Earth and related environmental sciences
Swedish Research Council for Environment Agricultural Sciences and
Spatial Planning
https://ror.org/03pjs1y45
2017-01949
2020-12-01T00:00:00Z
2020-12-01T00:00:00Z
en
151810856 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. Cumulative impact assessment (CIA) is a promising approach to guide
marine spatial planning (MSP) and management. One limitation of CIA is the
neglect of seascape connectivity, which may spread the impact of localised
pressures to ambient areas, e.g. through lost dispersal and recruitment of
organisms. 2. We here, for the first time, incorporate seascape
connectivity into a traditional CIA model using a connectivity matrix,
exemplified by dispersal of propagules estimated through biophysical
modelling. Two connectivity impactsare identified: the source
impact represents downstream areas losing recruits because of reduced
larval dispersal from sites affected by the pressure, and the sink
impact represents loss of recruits originating from upstream areas
prevented from settlement in the site affected by the local pressure. 3.
By including seascape connectivity into the Swedish MSP-guiding CIA tool
Symphony we demonstrate how to practically account for remote effects of
local environmental impact. Our example on blue mussel shows how reducing
mussel fitness in a given area may have impacts on mussels far from the
acting pressures. Overall, results indicate that connectivity impact for
blue mussels plays a minor role in most areas, less than 10% of the
ordinary cumulative impact. However, in some smaller areas, e.g. on
offshore banks and the Danish Straits, seascape connectivity may increase
ordinary cumulative impact with 20-30%. In an example of scenario-based
CIA analyses of MSP projections, we demonstrate how impacts of particular
management actions, e.g. shipping rerouting and wind power developments,
can be tracked far from the original area of influence. 4. Depending on
the dispersal ability of ecosystem components, a local pressure may impact
a considerable area through seascape connectivity, transgressing
management units and national borders. Although the mean connectivity
impact may be modest for a single ecosystem component, the consideration
of seascape connectivity across multiple ecosystem components may
significantly alter the mapping of cumulative impact and the assessment of
different MSP scenarios. 5. Synthesis and applications. Our extension of
Cumulative Impact Assessment offers a new method for mapping and
practically integrating seascape connectivity with ecosystem-based MSP and
other spatial instruments for policy making, such as marine protected
areas.
The article by Jonsson et al. in Journal of Applied Ecology presents an
extended model for the estimate of marine Cumulative Impact Assessment
(CIA) that includes seascape connectivity. We use a new CIA model
(Symphony) based on spatial data layers of human pressures and ecosystem
components (e.g. mussel reefs, seagrass beds, and photic soft sediments),
which covers the Swedish Exclusive Economic Zone in the North Sea and the
Baltic Sea. This CIA model is combined with modelled seascape connectivity
to show how estimates of connectivity can be implemented into a model of
CIA. As a demonstration we here consider the connectivity of blue mussel
(Mytilus edulis/trossulus) habitats represented by the dispersal of
planktonic mussel larvae. Dispersal was estimated with a biophysical
model, which simulates the dispersal trajectories of larvae in the
seascape from release to settlement. Dispersal probability between all
gridded locations in the seascape was summarised into a connectivity
matrix. With a set of Python and Cuda scripts the ordinary cumulative
impact was compared to the cumulative impact when also seascape
connectivity was considered.