Core Element 4: Ecological Linkages

Ecosystems are composed of many living and non-living parts. The parts—such as species, habitats, and nutrients—are connected with one another directly and indirectly. Changes in one part of the ecosystem can affect many other parts. Ecological linkages in the ocean are especially complex as many species travel long distances and the water carries nutrients, pollutants, and young animals from place to place. People are an important part of the ecosystem. Ecosystem-based management (EBM) explicitly recognizes these ecological linkages and uses knowledge of them to improve decision-making.

Focus Questions

  • What conceptual models are available for the ecosystem in the focal geographic area?
  • What are the key ecological linkages that should be given special attention in decision-making?
  • How could policy and management be changed to better account for ecological linkages?

Learn More

Listed below are selected resources for learning about and implementing this Core Element of EBM. The list is far from comprehensive and highlights only a few especially useful examples.


Conceptual models
Developing a conceptual model of an ecosystem or EBM project can help project participants come to a common understanding of and communicate about their ecosystem, threats to the ecosystem, and how potential management actions may change things.

Modeling ecological connections among places in the ocean

Modeling key ecological and socioeconomic processes

Special Issue on Marine Population Connectivity
Oceanography (Vol. 20, No.3, September 2007)


The DPSIR framework (Driving Forces-Pressures-State-Impacts-Responses) is used to assess and manage environmental problems.

UNESCO Marine Spatial Planning Initiative
Marine spatial planning (MSP) is one approach for considering ecological linkages to accomplish policy and management goals.

Integrated ecosystem assessment (IEA)
An IEA is a formal synthesis and quantitative analysis of information on relevant natural and socio–economic factors in relation to specified ecosystem management goals.

Seascapes: A Guide to Characterizing Marine and Coastal Areas
The Seascapes process for marine area characterization provides information on ecological linkages.


Tools for marine spatial planning
Marine spatial planning (MSP) is one approach for considering ecological linkages to accomplish policy and management goals.

Conceptual models
The development of conceptual models is a fairly well established field, and there are a number of tools available to help in developing them.

Coastal Transects Analysis Model (CTAM)
CTAM is a free, online, visualization tool that describes and analyzes, in a simplified fashion, the complex interactions between natural and human systems

CanVis Visual Simulation Tool

CanVis is a visualization program used to "see" potential impacts from coastal development or sea level rise.

Marine Geospatial Ecology Tools
Marine Geospatial Ecology Tools (MGET) is an open-source geoprocessing toolbox designed for coastal and marine researchers and GIS analysts who work with spatially-explicit ecological and oceanographic data in scientific or management workflows.

Nonpoint Source Pollution and Erosion Comparison Tool
The Nonpoint Source Pollution and Erosion Comparison Tool (N-SPECT) helps coastal managers and local officials to investigate potential impacts of development, other land uses, and climate change on water quality.

Ecopath with Ecosim and Ecospace (EwE)
This free suite of ecosystem modeling tools is one of the most user-friendly and least data-intensive whole-ecosystem models, although it does requires data that may be difficult to obtain in some places.

MIMES (Multiscale Integrated Model of the Earth System’s Ecological Services) is a modeling framework that is useful for understanding ecological linkages that generate nature's services.

Connection with other Core Elements (CEs) of EBM

CE1:Nature's Services
Ecological linkages generate nature's services.

CE2:Scientific Evidence
Scientific evidence is needed to understand ecological linkages.

CE3:Geographic Scales
The geographic scale of an EBM initiative affects the role and importance of different ecological linkages.

CE5:Cumulative Impacts
Ecological linkages can magnify or reduce the cumulative impacts of human activities.

CE6:Tradeoffs Among Human Activities
Ecological linkages are one factor that leads to tradeoffs among human activities.

CE7:Adaptive Management
Ecological linkages can result in unanticipated outcomes of management actions, making adaptive management essential.

CE8:Network of People and Information
People engaged in EBM need to know about ecological linkages.


Read about Core Element 5: Cumulative Impacts