What is a seascape?

Square

Ecologists typically use the word ‘landscape’ to refer to mosaics of interacting ecosystems that become evident when you zoom out from a single habitat. Though these mosaics can occur at any spatial scale, landscape ecology tends to focus on ecological patterns and processes that occur at across 100s of meters to 10s of kilometers.

Though landscape ecology has a long academic history, seascape ecology is a rather new idea.

In a recent book edited by Simon Pittman, seascapes are defined as: “spatially heterogeneous and dynamic [marine] spaces that can be delineated at a wide range of scales in time and space.” In seascape ecology, as in landscape ecology, species composition, diversity, and other characteristics of ecological communities are modelled in relation to intermixed habitat patches and spatially variable factors of interest, such as temperature or predator density.

While the academic literature on both seascape and landscape ecology is thick with complex theoretical frameworks, intensive quantitative modelling, and very large, tricky datasets, it maintains several core themes that may be helpful in anticipating the potential impacts of and ecological tools for seascape design in urban areas:

  • Patches/Mosaics: Seascapes consist of patches or mosaics of interacting ecosystems, such as sandflats, seagrass beds, or rocky reefs, that are dynamic and variable at multiple spatial and temporal scales. Seascapes that are more spatially heterogeneous, that is that contain a wider variety of patch types, topographies, or habitats, tend to support greater diversity.
  • Connectivity/Ecological Flows: Connectivity and ecological flows, such as the movement of detrital kelp, predators, plankton, and invasive species, are key features of seascapes that strongly influence the composition and diversity of marine organisms. Designs that block the movement of larvae, food resources, or mobile animals can therefore negatively impact seascape dynamics and ecosystems. Similarly, designs that reduce connectivity may be of interest where prevention of invasion by a well-studied non-native species is the top concern.
  • Boundaries: Organisms that live along the boundary between patches are subject to unique biotic and abiotic conditions, and in turn, they help determine how the rest of the community in that patch is influenced by adjacent ecosystems. For instance, mangroves and marsh grasses that inhabit the boundary between land and sea help to filter land-based contaminants for marine life in adjacent areas while also serving as a buffer between human communities and storm surge. Boundaries can therefore be helpful design tools.