What is Ecosystem Mapping?
The primary purpose of Ecosystem Mapping is to identify which parts of the natural system are important for the supply of ecosystem services.
The process of developing maps helps to identify the value of natural components of these systems (such as woodland, wetland or green infrastructure). More advanced ecosystem mapping visualises the flow of benefits (or disbenefits) from ecosystems to human populations, feeding into valuation work and for targeting interventions to address needs.
Maps will change as conditions change, either through natural or managed processes, and can both document these changes and can help to anticipate consequences. Finally, maps provide an intuitive means for communicating what can often be quite complex (and unfamiliar) information about ecosystem services to a broad range of people.
An example of an ecosystem map using the Polyscape approach is included in the short Polyscapes Tool Review. The maps represent trade-offs and synergies of the impacts of tree cover between four ecosystem services at Pontbren farms in Mid Wales. On the individual maps the red areas represent high value for the service and green areas opportunities for change. In the combined map the red areas represent trade-offs whilst green areas represent areas where changes will provide multiple benefits.
How does it work?
Ecosystem Mapping has a wide number of potential applications and, as such, there is no generic prescription available for generating maps. This makes the process of generating maps difficult for many users. Key issues that may affect this process include: variations in how individual ecosystem services are mapped (including availability of appropriate methodologies, indicators and expertise); identification of appropriate scale to map clusters of ecosystem services (which often have different system boundaries); availability, resolution and precision of data and variability in map function and audience requirements.
Initial maps are generated for each ecosystem service. Ideally this would include all ecosystem services but in practice is often narrowed down to key services (usually between one and six). This may involve using established methodologies (for example mapping impacts of tree cover on urban heat islands) or it may require development of new or customised methods depending on a number of factors (map function, data availability, available expertise, cost and scale).
Generating maps for each ecosystem service will have different data requirements. In some instances data generated for other purposes can be used (with caveats), but in many instances data will not be available – particularly socio-ecological data. In many instances proxies can be used (although limitations should be made clear). At present we tend to see a bias towards services that are ‘easier’ to map (for example carbon sequestration, recreation and food production). These gaps can be partly addressed by using participatory mapping approaches – where local people and experts work in close partnership to co-develop maps (read the short Participatory Mapping tool review for more information).
Once maps for individual services are generated then these can be used to develop composite maps visualising interactions between ecosystem services; important for identifying areas of synergy (hotspots) or areas where services are required to meet needs.
What decisions is it used for?
Maps are important across the spectrum of activities associated with the Ecosystem Approach and are fundamental to Ecosystem Assessments. At a basic level maps allow planners to identify where stocks of natural capital (such as woodlands, lakes or green infrastructure) within a specified system are important for delivering ecosystem services. This may be at a range of scales (neighbourhood or farm, city/local authority, region and national). This informs basic valuation of these areas; particularly hotspot areas that provide multiple benefits. Mapping changes in land cover over time (either through historical mapping or through scenario mapping) can provide valuable information highlighting consequences of particular land-use changes or policy interventions.
Identification of ‘flow pathways’ between ecosystems and beneficiaries (enabling identification of winners and losers) is important for more precise valuation. This allows more targeted interventions and makes explicit trade-offs resulting from land use change. This is currently very challenging for most ecosystem services and some of the more complex models have only just begun to address this issue (for example, read the short ARIES tool review).
The process of mapping should also provide information about the data needs. In most instances there is unlikely to be appropriate data available to map all ecosystem services so the process of developing maps will make this clear. As each ecosystem service has different data requirements some thought needs to be given to how different data sets relate to each other.
When is it used?
Mapping is a fundamental first step to ecosystem services management. Holistic understanding of the benefits that nature provides depends on clear identification of where (and when) ecosystems functions are generated and where these benefits are received (i.e. the point at which functions become services). While there are a number of mapping approaches/tools that can be applied relatively easily around individual ecosystem service (although these will not be badged as ecosystem service tools), ecosystem services mapping requires us to think about the interrelationships between these maps both for the same ecosystem service at different scales and between ecosystem services. This includes clear identification of not only which components are important (but information about their condition and understanding their relative value and associated uncertainties).
For valuation and strategic decision making exploring the impact of alternate scenarios more complex modelling approaches may be required (for example, read more about ARIES and InVEST in the short tool reviews). These modelling approaches have limitations particularly around data requirements and modelling experience and may require customisation for specific locations. It is important that users are familiar enough with the models and the Ecosystem Approach generally to understand the limitations of these tools for decision-making.
In addition, whilst maps are powerful communication tools, the lack of data at present (particularly at finer scales) often forces the use of proxies. There can be problems with this which makes it important to communicate uncertainty (which can be challenging with visual tools). At present, given the significant data gaps, the process of developing ecosystem maps is often as important as the final products. Assessing data requirements for maps will identify key knowledge gaps. The process also requires different experts to work together (fostering interdisciplinary activity) and the use of local knowledge (both to inform and ‘ground truth’ maps). Building these collaborative partnerships will often encourage engagement with the decision-making process. More information about participatory working can be found in the Engagement tools tree root.
Ecosystem Mapping in Wales (SCCAN)
Natural Resources Wales’ SCCAN (Natural Resource Planning Support System in Welsh) project aims to provide an ecosystem service mapping system which allows users to weigh up and set priorities for the many competing demands that are placed on the environment.
Land Utilisation & Capability Indicator (LUCI) mapping
The Land Utilisation and Capability Indicator (LUCI) model allows the mapping of ecosystem services from the sub-field to national scale, the impact of management services on these services, likely trade-offs, and opportunities for spatially optimising interventions. Currently services include agricultural productivity, flood risk, erosion, nitrogen, phosphorus loss to rivers, carbon storage and emission rates, habitat diversity, and connectivity for broadleaved woodland species.
Additional tool reviews using expert-led GIS: InVEST - ARIES - MIMES - POLYSCAPES