Desertification and land degradation: origins, processes and solutions

Table of Contents

1. Authors and acknowledgements
2. Introduction
   1. Aims
   2. Definitions and key concepts
   3. Synthesis of previous and ongoing projects
   4. Key issues and outline
3. Evolution of desertification in the Mediterranean
   1. Climatic fluctuation
   2. Human influence
4. Primary drivers of desertification
   1. Biophysical and socio-economic causes
   2. Pathways of desertification
   3. Driving forces in the Mediterranean
   4. Synthesis of causes for DESIRE hotspots
   5. Conclusions
5. Processes and consequences of desertification in the Mediterranean
   1. Socio-economic and political factors
   2. Biophysical processes
   3. Conclusions
6. Indicators: monitoring desertification
   1. History of monitoring
   2. Indicators
   3. Monitoring and mapping techniques
   4. Concluding remarks
7. Modelling desertification
   1. Definition of modelling
   2. Model types
   3. Biophysical modelling
   4. Socio-economic and participatory modelling
   5. Gaps and progression in modelling
8. Solutions
   1. Biophysical solutions
   2. Political and socio-economic solutions
9. References

Synthesis of previous and ongoing projects

In Appendix II a list of ongoing and past projects related to desertification is given. Many projects have been carried out, each with its own specialization, approach, expertise and specific objectives. Here, a synthesis of these projects is given that places them in a broader context. Classification has been carried out according to two criteria: type of project and their objectives (see Tables 1.1and 1.2).

In this comparative study, the two Tables 1.1 and 1.2 give an example of two ways to classify desertification related projects. In this way, an overview can be obtained from the overwhelming number of projects and they can be compared to each other without losing their identity as individual project with specific aims and foci.

Type of project and aim

Here, the type of project was chosen in the first instance, leading to databases, networks (e.g. to enhance collaboration and coordination in a certain field related to desertification), programmes (e.g. broad programmes that have several sub-projects) and projects. The latter are subdivided according to their aim or starting point:

• Projects that develop new technologies, methods or insight without using the results of previous projects. From analysis it has emerged that these kinds of projects are mainly past rather than present projects. As the number of projects and thus the results have increased, more recent projects usually start from the results of the projects of this category.
• Projects that start from previous projects' results and build on these to translate their results plus added insights and methods into useful tools and guidelines for end-users (e.g. policy makers).
• Projects that aim to compile information of a certain field. This information, usually from other related projects, exists but is inaccessible or scattered. These projects aim to compile this information and mostly also function as a discussion platform (thus related to the category 'networks').
• Projects that aim to improve the communication between involved parties in a certain field related to desertification.

Table 1.1: Desertification projects organized in categories regarding type of project and aim

As can be seen from Table 1.1, most projects reviewed here are projects which focus on developing new insights, technologies or methods while they use limited information from other projects. An example of a very large project is MEDALUS, which has had three phases. Later projects almost always refer to MEDALUS and use knowledge that is acquired in this project.

In Table 1.1, some projects are placed in brackets and appear in more than one category. In these cases, it was difficult to place the project under one heading. For instance, DESERTLINKS used information from earlier projects but also developed a new indicator system. Most projects do not belong strictly to one category. However, it was the objective of this synthesis to classify the projects, so they are placed in the category into which they fitted best. As has been said, this does not mean that projects of one category are the same as they all have their individual focus.

Objectives

Another criterion by which to categorize the projects is their objective regarding the intention of how to deal with desertification. In Table 1.2, this criterion is used leading to the following categories:

• Policy-oriented, including management and decision making;
• Improvement of knowledge on e.g. the causes, status, mechanisms or impact of desertification;
• Practical activities or techniques;
• Identifying problems related to desertification;
• Identifying solutions
• (Use of) indicators
• Monitoring desertification, e.g. through remote sensing
• Other

Table 1.2: Desertification projects organized in categories regarding content of project

Almost all projects have as (part of) their objectives to improve sustainable development. As this is an overall objective of all projects, it is not taken into account in the classification. Apparent from Table 1.2 is that most projects are policy or management oriented. However, while many projects have sustainable management as their final objective, in their specific objectives they include several activities that relate to the final objective (e.g. the SENSOR project aims to develop tools to support decision-making). The activities in the second category (improvement of knowledge regarding the causes, status, mechanism and impact of desertification) range from developing, testing and applying methodologies for the investigation of impacts (MEDAFOR), to forming a binding link between the scientists who aim to investigate the complex causes and effects of desertification (Desert*Net). This example indicates the breadth of the categories and the diversity of projects that fall within one category. The third category includes projects that aim to deliver practical guidelines or new techniques, mostly in a specific field of desertification, e.g. the use of vegetation (RECONDES), or the development of methods to combine diverse stakeholder knowledge with cutting-edge science in Sustainable Uplands. The fourth category, identifying problems, is somewhat indistinct and includes projects that aim, for example, at assessing the vulnerability (VULCAN), the development and testing of a new desertification paradigm (ARIDnet). In the category of monitoring desertification, remote sensing and GIS play an important role (e.g. ASMODE, DEMON). The last category consists of projects that are too specific and could not be classified in one of the other categories. CLEMDES aims at the diffusion of information; CLIMED's objective is to provide information on climate change; GLASOD produced a global map of soil degradation; MWISED is focused on within-storm dynamics and the (erosive) effects; and PESERA developed, calibrated and validated a model to quantify soil erosion at the regional scale.