A key aspect of EBM is the choice of management options that can target the major threats to the different aspects of the ecosystem. The ODEMM Pressure and Ecological Risk Assessments allow the main threats to be identified and indicate the links between components and human activities. The ODEMM integrated Management Strategy Evaluation (iMSE) tool can be used to link types of management options with the categories of the Pressure Assessment, allowing different manageable aspects of human activities to be targeted to address the main threats in the system. Management options can focus on drivers, pressures, ecological components or combinations of these.
The ODEMM iMSE tool is a comprehensive framework that aims to provide guidance for the identification and selection of consistently defined management options and allows an evaluation of these options to achieve policy objectives through their reduction of risk.
The iMSE tool is based on the Ecological Risk Assessment consisting of Driver-Pressure-State combinations (“impact chains”) that each contribute to the risk of not achieving policy objectives. The two aspects of risk, Impact Risk and Recovery Lag, are determined by five assessment criteria (from the Pressure Assessment) (Figure 1).
Figure 1 The iMSE tool which links potential management options through the Types of Measures to the Pressure Assessment criteria and ultimately to the two components of the Risk Assessment
The tool considers two distinct aspects of a management measure: the Focus and the Type of measure.
The Focus is determined by the part of the impact chain (Driver-Pressure-State) the measure is supposed to mitigate. A management measure may focus on one element in the impact chain (Driver, Pressure or State), the combination of two elements (Driver-Pressure or Pressure-State) or three elements (Driver-Pressure-State, which means the aim is on one specific impact chain). Thus, the measure becomes more specific as more elements are combined.
The Type represents the physical measure which affects the impact chain directly. We use six types of measure, loosely based on the MSFD, that each link differently to the risk criteria (Figure 1). The options “Spatial distribution controls”, “Temporal distribution controls”, “Input control” and “Output control” each (or in combination) mitigate the Impact Risk, while “Remediation”, and “Restoration” mitigate the Recovery Lag. In addition the tool calculates Total Risk which is the product of Impact Risk and the Recovery Lag.
Using the iMSE
In the application of the iMSE tool, the performance of a management measure (in terms of its reduction of risk) depends on (a) the number of impact chain(s) and (b) the risk criteria associated with that measure. The performance is assessed based on an explicit consideration of three time horizons for management with the relevant aspect of risk:
- Past: management aimed at reducing existing adverse impacts from past activities. This is based on Recovery Lag.
- Present: management aimed at current activities based on preventing/reducing the likelihood they will cause an adverse impact. This is based on Impact Risk.
- Future: management aimed at current activities but considering both the likelihood of an adverse impact as well as the time it takes to return to pre-impacted condition after the implementation management. This is based on the Total Risk (Impact Risk x Recovery Lag).
The output of using the tool is a ranked order of a suite of potential management options in terms of the reduction in Impact Risk, Recovery Lag and Total Risk. The tool shows that management options cause different reductions in the three aspects of risk and these correspond to the three time horizons for management considered.
The Type and Focus of the management option determines which pressure assessment criteria and aspects of risk are mitigated. For example, an output control such as creating a system for identification of oil spills, focuses on a Driver (Oil & Gas) - Pressure (Non-synthetic compounds) combination and has the potential to reduce Impact Risk through tackling the Degree of Impact from this sector-pressure (see Number 3 in Tables 1 and 2). A restoration control such as optimising the shape of burrow pits for ecological development, focuses on a Driver (Aggregates) - Pressure (Abrasian, Extraction) - State (Seafloor habitats) combination and has the potential to reduce Recovery Lag (See Number 4 in Tables 1 and 2).
Table 1 Possible combinations of Focus and Type of measures. The numbers in the cells correspond to the management measures in Table 2.
Table 2 Example potential management options, the number of impact chains affected and the maximum potential reduction that can be achieved in the options are fully implemented. (RL = Recovery Lag, IR = Impact Risk, TR = Total Risk).
The results in this example show that the management options can be ranked 2, 1, 3, 4 in terms of their effectiveness in reducing Total Risk.
At this stage in development, interested users should contact the main tool contacts for discussion on possible applications. In order to fully understand what underlies outputs users would need to understand how the pressure assessment and then risk assessment were used to generate risk. At this time it would be possible to use the too to compare managament strategies for application at the broad scale of regional seas in Europe with the data already available. Applications at different levels of spatial or temporal resolution would require further work in order to first revise the underlying assessment data.
The method is also described in Chapter 6 of ODEMM's final deliverable (Robinson et al. (2014) - ODEMM Report.pdf)
In addition, an example of the application of this approach to Europe's regional seas has been published in Biological Conservation (Piet et al., 2015. Biological Conservation 186, 158–166).
Developers: Gerjan Piet, Ruud Jongbloed, Antony Knights, Jacqueline Tamis, Anneke Paijimans, Marieken Van der Sluis, Pepijn de Vries and Leonie Robinson