Critical Habitat Mapping
Image credit: Hatfield Consultants
| || |
EO data can support assessment of critical habitat when experts integrate and evaluate the status of key biophysical factors that are used to determine critical habitat.
Habitat mapping and assessment covers diverse environments depending on a project’s needs, including: terrestrial, freshwater aquatic, and coastal foreshore / intertidal. Habitat assessment and monitoring is a requirement in many jurisdictions under legislation such as national or state environmental assessment acts, and may also be required to meet international standards (e.g., International Finance Corporation Performance Standard 6: Biodiversity Conservation and Sustainable Management of Living Natural Resources).
Terrestrial habitat is influenced by factors such as latitude, altitude, aspect, and regional climatic parameters including temperature, moisture and wind regimes (e.g. WWF Ecoregions), many of which can be estimated from EO methods. Soils and available nutrients further influence habitat types and vegetation species, which in turn govern animal distribution and abundance patterns. An important issue for terrestrial habitat assessment is fragmentation. Methods developed in landscape ecology can be employed to evaluate landscape structure, and estimate effects on biodiversity. Metrics such as patch size, isolation, and edge effects and linear disturbance can all be evaluated from EO-derived land cover information. Water availability and quality is important in defining terrestrial and freshwater aquatic habitat. EO methods can be used to determine lake and river extent, and changes in extent and volume. Hydrological analysis to determine catchments and stream gradients may useful for determining limits of fish ranges. Wetland habitat can be evaluated for its extent, seasonality and distribution.
Coastal marine habitat
These environments are influenced by conditions in adjacent terrestrial and marine environments, and in turn can have far reaching effects on adjacent terrestrial systems. They provide important habitat for a diversity of wildlife that includes shorebirds, intertidal invertebrates, and coastal fish. Several aspects of coastal foreshore/intertidal critical habitat can be mapped and monitored by EO in similar ways as for freshwater. The extent of important habitat such as mangroves and seagrass can be monitored from EO methods, with improved hyperspectral satellite sensors increasing the efficacy of habitat delineation (e.g., HSI aboard EnMAP). Monitoring of tidal range (low and high water marks) and tidal flat extent (which constitutes important habitat) is possible from EO (optical and radar).
“Critical habitat” extent is defined as part of corporate commitments to avoid environmental and social impacts, usually according to a standard such as the IFC Performance Standard 6. Critical habitat products would include summary information regarding the criteria used by experts to define critical habitat, in large part based on EO derived products and GIS analysis.
Known restrictions / limitations
Lifecycle stage and demand
Pre-license/Exploration: Disturbance inventories and effects of cumulative impacts are assessed to put prospective development into a regional context. Protected or critical areas affect exploration and development planning.
Development: Baseline environmental assessment and environmental impact assessment to avoid critical habitat impacts or implement appropriate mitigations. Construction monitoring.
Production: monitoring for potential impacts of production activities on critical habitat.
Decommissioning: Remediation or enhancement of habitat. Monitoring success of decommissioning.
Geographic coverage and demand
Demand is global, especially in areas of highly developed or fragmented natural habitat or where unique critical habitat is known to exist.
OTM:032 Detecting ecosystem damages
Input data sources
Optical: VHR1 or VHR2 (bathymetry and tidal range), HR1, HR2, MR1, MR2
Supporting data: Wildlife range maps, soils information, and climatology
Spatial resolution and coverage
5–30 m for land use / land cover classes and water extent (optical and radar).
1 m or better for bathymetry.
90+ m for thermal imaging.
Minimum Mapping Unit (MMU)
Areas between approximately 5 to 40 hectares represent minimum terrestrial habitat patch sizes for many wildlife species; however, sensor resolution allows accurate classification of features as small as approximately 400 m2 (at 5 m resolution).
Accuracy / constraints
Thematic accuracy: land cover/land use and water extent 80-90%.
Spatial accuracy: As determined from component products.
Accuracy assessment approach & quality control measures
Statistical confusion matrix with user’s and producer’s accuracy for land cover / land use and water extent. In-situ measurements.
Frequency / timeliness
Observation frequency: Based on frequency of satellite imagery, but typically 2 – 20 days. Habitat should be evaluated early in the project life cycle and monitored yearly.
Timeliness of delivery: Initial product outputs can be derived quickly (1 – 2 days). Analysis, modelling and mapping require more time (2 – 4 weeks).
On-demand availability from commercial suppliers.
New acquisitions can be requested globally.
Delivery / output format
|Lead Author:||Hatfield Consultants|
Critical Habitat Mapping
# of Pages:
Internal – Project consortium and science partners
External – ESA
This page has no comments.