Habitat Features and Their Influence on the Restoration Potential of Marine Habitats in Europe

Abstract

To understand the restoration potential of degraded habitats, it is important to know the key processes and habitat features that allow for recovery after disturbance. As part of the EU (Horizon 2020) funded MERCES project, a group of European experts compiled and assessed current knowledge, from both past and ongoing restoration efforts, within the Mediterranean Sea, the Baltic Sea, and the NorthEast Atlantic Ocean. The aim was to provide an expert judgment of how different habitat features could impact restoration success and enhance the recovery of marine habitats. A set of biological and ecological features (i.e., life-history traits, population connectivity, spatial distribution, structural complexity, and the potential for regime shifts) were identified and scored according to their contribution to the successful accomplishment of habitat restoration for five habitats: seagrass meadows, kelp forests, Cystoseira macroalgal beds, coralligenous assemblages and cold-water coral habitats. The expert group concluded that most of the kelp forests features facilitate successful restoration, while the features for the coralligenous assemblages and the cold-water coral habitat did not promote successful restoration. For the other habitats the conclusions were much more variable. The lack of knowledge on the relationship between acting pressures and resulting changes in the ecological state of habitats is a major challenge for implementing restoration actions. This paper provides an overview of essential features that can affect restoration success in marine habitats of key importance for valuable ecosystem services.

Restoration of Cymodocea nodosa seagrass meadows: efficiency and ecological implications

“…(1) the seagrass growth rate and reproduction cycle (i.e. the slow-growing species will require longer time scales for recovery than the fast-growing species); (2) the characteristics of the donor population (genetic diversity, spatial distribution, structural complexity, and the potential for regime shift; Bekkby et al 2020); (3) the distance from the donor site in which the restoration action is carried out; and (4) the methodology utilized (Paling et al 2009). An ideal restoration site should have high recovery potential (i.e.…”

Marine ecosystem restoration in a changing ocean

“…Direct and indirect human pressures on marine ecosystems will likely increase in the next few decades, leading to significant loss and continued fragmentation of marine habitats and their biodiversity, and to impairment of ecosystem processes and functions (Gerovasileiou et al 2019;Bekkby et al 2020). Marine biodiversity loss can fundamentally alter ocean functioning (e.g.…”

“…(2) identification of the best restoration protocols for the recovery target species/habitat; (3) influence of positive species interactions (some species improve the survival of other species by providing habitat or refuge), which may expedite recovery, and, in the longer term; (4) understanding of the drivers, feedback effects, and critical thresholds, including positive and negative interactions among species and local/ global stressors (Bekkby et al 2020).…”

Using Propagules to Restore Coastal Marine Ecosystems

“…High fecundity, efficient dispersal and fast growth are all traits that should enable kelps to recolonize extensive areas from a few reproducing parents if suitable conditions exist for survival and growth. There have been multiple efforts to regrow lost or declining kelp forests (reviewed in Layton et al, 2018;Bekkby et al, 2020;Fredriksen et al, 2020), typically through either assisted recovery, in which the focus is on restoring conditions favorable for survival and growth, or active restoration in which kelps are reintroduced to target areas.…”