PESERA-DESMICE: Land management evaluation model

Table of Contents

1. Authors
2. Summary
3. Acronyms
4. Introduction
5. Coarse-scale model description
   1. The PESERA model: summary
   2. Alternative approaches to assessing soil erosion
   3. Process representation in PESERA
   4. Extensions of PESERA
   5. Adapting PESERA
   6. Assessment at catchment scales
6. Cost-effectiveness modelling
   1. Step 1
   2. Step 2
   3. Step 3
   4. Step 4
   5. Step 5
   6. Step 6
   7. Step 7
   8. Step 8
   9. Step 9
   10. Step 10
   11. Step 11
   12. Step 12
7. Agent-Based modelling in Spain
   1. Phase 1
   2. Phase 2
   3. Phase 3
   4. Phase 4
   5. Phase 5
   6. Phase 6
8. Input-Output modelling in Spain
   1. Model construction
   2. Scenario analyses
9. References

Step 10

Step 10: Delineating areas of particular economic interest/vulnerability to off-site effects

Besides on-site effects, remediation technologies may also mitigate off-site or downstream effects of land degradation. Some of these off-site effects will be particularly relevant for confined areas. As PESERA has its limitations in that it treats grid cells as independent units, it cannot be used directly to assess off-site effects. This step details how PESERA can still be used to assess off-site effects in an indirect fashion. Thereto, first for each effect the area of interest will be delineated. Delineation of such areas should be done both for a with and without situation to allow for the subsequent valuation of differences in economic terms (step 11). The most relevant (and currently the only) off-site effect which can be considered for soil erosion is reservoir sedimentation. Use will be made of the sedimentation database developed by KU Leuven (Partner 2), of which some details are included in section 2.2. The remainder of this step explains the method for doing this.

A map layer with reservoirs should be created, and its attribute table be completed with details of construction costs and reservoir volume. For each reservoir the contributing catchment area will subsequently be calculated. PESERA output (step 9) includes soil erosion values for each grid cell. These should be summed for the catchment areas. The relation between the soil loss from grid cells and reservoir sedimentation is formed by a Sediment Delivery Ratio (SDR) (i.e. only a certain fraction of sediments leaving the area end up in the reservoir). Section 2.2 briefly reports on ongoing work to construct a database of SDR values. Rules will be applied to select the appropriate SDR for each reservoir (catchment area). One way of doing this is to establish a SDR based on the distance from a grid cell, through the drainage network, to the reservoir. Multiplying soil loss with SDR gives a cell's contribution to annual reservoir sedimentation. Summing all individual cell contributions and multiplying sedimentation with specific density of sediments, the reservoir volume capacity lost can be calculated, and (in step 11) valued.

Data sources: 1) reservoir map layer with relevant attributes; 2) relevant PESERA output maps (soil erosion)

Intermediate products: 1) maps with areas of particular economic interest/ vulnerability for both with and without situation to off-site effects; 2) maps/data of (areas with) calculated actual damage (i.e. reservoir volume capacity loss)