NCEA Saltmarsh Analysis-Ready Data: Extent and Change in England

Over 95% of England's saltmarsh extent has been mapped to zonation level using aerial photography from 2016-2024. The dataset, produced by the Environment Agency and Natural England, includes layers for extent, zonation, and change compared to a 2006-2009 baseline. It provides evidence of accretion and erosion for ecological monitoring and coastal risk management.

Use Cases

• Monitor saltmarsh habitat gain and loss based on the change layer comparing 2006-2009 and 2016-2024 extents.
• Analyze ecological community distribution based on zonation classes like Pioneer, Spartina, Mid-low, and Upper Marsh.
• Assess coastal flood and erosion risk based on spatial evidence of saltmarsh accretion and erosion.
• Support Natural Capital Ecosystem Assessments based on mapped extent and zonation data.
• Ground-truth remote sensing classifications using data collected through national monitoring programmes from 2023 onwards.

Strengths

• Over 95% of the national saltmarsh extent is mapped to zonation level.
• Change analysis compares a baseline (2006-2009) with a recent version (2016-2024), covering almost 100% of England's saltmarsh.
• Data layers were ground-truthed using monitoring programmes from the Environment Agency and Natural England.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The landward and seaward extent demarcation relies on a 5% vegetation cover threshold, which may introduce classification edge cases.

Provenance

Source

Environment Agency

Collection Method

Mapped from aerial photography and ground-truthed through national monitoring programmes.

Time Range

Baseline: 2006-2009; Recent extent and zonation: predominantly 2016-2024.

Freshness

Last updated 2026-04-17 13:12:50.694966; freshness should be verified.

Geography

England