Internationally recognised tools for understanding, assessing and managing estuarine, coastal and marine systems.
IECS has played a central role in developing several conceptual and operational frameworks that are now used internationally in marine management, environmental assessment, governance and risk analysis. These frameworks integrate natural and social sciences, support evidence‑based decision‑making, and help practitioners navigate the complexity of human–nature interactions.
“IECS is recognised for developing and refining several conceptual frameworks that integrate natural and social sciences in Marine Management.”
This page introduces our core frameworks, explains their purpose, and outlines how they support sustainable marine governance.
A comprehensive cause–consequence–response framework for human–nature interactions.
The Drivers–Activities–Pressures–State Change–Impacts on human Welfare–Responses as Measures framework – pronounced “dap‑see‑worm” – is one of the most widely used tools for structuring environmental problems.
It evolved from earlier models such as PER and DPSIR, but goes further by explicitly separating:
- Environmental change (State Change)
- Societal consequences (Impacts on human Welfare)
- Management actions (Responses as Measures)
This separation is crucial for modern marine governance, where ecological, economic and social dimensions must be considered together.
What DAPSI(W)R(M) does
- Provides a holistic structure for understanding how human activities affect ecosystems.
- Helps identify where interventions are most effective.
- Supports risk governance, policy development, and adaptive management.
- Ensures that management responses are linked to specific pressures and impacts, not generic or disconnected.
A minimum‑complexity framework for modelling marine systems.
Marine systems are complex, adaptive and dynamic. Practitioners often struggle to balance biodiversity conservation with economic and social needs. Simple SES was developed to address this challenge.
It integrates concepts from systems thinking and social‑ecological science into a three‑phase operational model:
- Setting Priorities
- Gathering Information
- Using Information
DAPSI(W)R(M) sits at the centre of Simple SES as the primary problem‑structuring tool.
What Simple SES does
- Reduces complexity to the minimum necessary for effective decision‑making.
- Helps managers identify leverage points for intervention.
- Supports co‑design with stakeholders.
- Enables scenario testing and adaptive management.
- Bridges the gap between science, policy and practice.
An ISO‑aligned risk assessment tool adapted for biodiversity and ecosystem management.
Bow‑tie analysis is widely used in engineering and safety management. IECS adapted it for marine biodiversity, creating a powerful visual tool for mapping:
- Causes (human activities and pressures)
- The central event (e.g., biodiversity loss, habitat degradation)
- Consequences (ecological and societal impacts)
- Control measures (preventative, mitigative, compensatory)
The result is a clear, communicable diagram that shows how risks arise and how they can be managed.
What Bow‑Tie does
- Makes complex risk pathways easy to understand.
- Identifies critical control points.
- Supports ISO‑aligned risk governance.
- Integrates seamlessly with DAPSI(W)R(M).
- Helps organisations prioritise measures that matter.
A set of criteria defining what makes a management measure effective, feasible and sustainable.
The Ten Tenets outline the fundamental requirements for any environmental management action to succeed.
A measure must be:
- Ecologically Sustainable
- Technologically Feasible
- Economically Viable
- Socially Desirable
- Legally Permissible
- Administratively Achievable
- Politically Expedient
- Ethically Defensible
- Culturally Inclusive
- Effectively Communicable
What the Ten Tenets do
- Provide a checklist for evaluating management options.
- Ensure decisions are balanced across ecological, social and economic dimensions.
- Help identify barriers to implementation.
- Support transparent, defensible decision‑making.
Explaining why estuaries challenge conventional ecological assessment.
Estuaries are naturally stressed, highly variable environments. They experience:
- Rapid salinity changes
- Strong hydromorphological forces
- High turbidity
- Naturally low species richness
The Estuarine Quality Paradox highlights that these natural stressors can resemble human‑induced degradation, making it difficult to assess ecological status accurately.
What the Paradox does
- Helps practitioners distinguish natural variability from anthropogenic impact.
- Supports more realistic ecological targets.
- Prevents misclassification of estuarine health.
- Underpins many IECS ecological assessments.
A structured approach to mapping the spatial and temporal extent of human impacts.
Developed by IECS, this framework separates three critical components:
- Activity Footprint – where and when an activity occurs
- Pressures Footprint – how far the pressure propagates
- Effects Footprint – where ecological and societal impacts occur
Effects footprints can be larger, longer‑lasting and more diffuse than the activity itself.
What Footprint Analysis does
- Reveals hidden or far‑field impacts.
- Supports cumulative effects assessment.
- Helps prioritise mitigation and monitoring.
- Provides a clear structure for transboundary management.
A typology for transboundary marine governance.
IECS developed this typology to address challenges in cross‑border marine management.
- Connectivity – physical, ecological and socio‑economic linkages
- Coherence – alignment of policies, plans and protected areas
- Equivalence – comparable outcomes even when methods differ
What the typology does
- Supports international cooperation.
- Helps harmonise monitoring, assessment and reporting.
- Ensures fair and effective management across borders.
- Strengthens regional governance frameworks.
A tool to assess the ecological value of the qualities of marine ecosystems.
The inherent ecological value of an ecosystem is associated to its biodiversity and the ecosystem components that contribute to it. EVA was developed to assess value in non-monetary terms and its distribution in the study area.
EVA evolved from earlier marine biological valuation approaches to obtain a more flexible and widely applicable assessment tool that:
- Incorporates the biodiversity metrics on multiple ecosystem components, including both habitat and species assemblages
- Accounts for both their structural and functional qualities, including their rarity (at multiple scales) and the role they play in supporting ecosystem functioning (ecological significance)
- Requires monitoring data and ecological knowledge for better performance, but may be also applied in knowledge/data-poor cases by using modelling results or expert judgement as evidence sources
- Provides a measure of confidence in the results, accounting for data quantity and quality and assessment performance.
The result is a set of maps that show how the ecological value (overall and by Ecosystem Component) is distributed within the selected study area.
What EVA does
- Valuates the qualities of an ecosystem from an eco-centric perspective, regardless of anthropogenic uses or social interests
- Quantifies where biodiversity holds the highest ecological significance in an area, thereby supporting decision-making in conservation, marine spatial planning, and ecosystem-based management
- Provides a harmonised, transparent, and flexible approach with results that can be aggregated or disaggregated to aid interpretation, and with confidence estimate to support use of the results.
A Decision Support Tool to assist practitioners with identifying the optimal assessment tools that may be used to support Ecosystem-Based Management.
Ecosystem‑based management (EBM) is fundamental for sustaining healthy, productive, and resilient marine ecosystems while ensuring the continued delivery of ecosystem services that underpin human well‑being. A wide range of assessment methods and tools exist to support this process but no single tool provides optimal support across all possible EBM applications.
SEAS4GES was developed to assist practitioners with identifying the optimal tools to support the implementation of EBM. It works by:
- Gathering information from the user about their EBM assessment needs, data availability and skills
- Comparing this information with the characteristics of 35 tools (within 18 generic tool types) commonly used by scientists and practitioners
- Ranking the tools based on their ability to meet the user’s needs and abilities
- Providing aggregated and disaggregated results in matrix, list and graphic forms.
SEAS4GES is provided as a user-friendly interface in Excel.
What SEAS4GES does
- Streamlines the EBM process by helping practitioners in choosing the best assessment tool(s) for their EBM needs
- Supports the choice with information about the tools selected (factsheets)
- Provides insight into the strength or weakness of different tools relative to the specific conditions surrounding their use
Visual tools for simplifying complex marine legislation and administrative structures.
Marine governance is notoriously complex, involving:
- International conventions
- National legislation
- Regional bodies
- Local authorities
- Sector‑specific regulators
IECS developed horrendograms (for policies) and organograms (for administrations) to make these systems understandable.
What they do
- Reveal overlaps, gaps and inconsistencies.
- Support policy coherence.
- Help stakeholders understand who does what and why.
- Provide a foundation for governance reform.
IECS provides training, guidance and applied support for organisations wishing to use these frameworks in policy, planning, assessment or research.