Database of study site indicators

Table of Contents

1. Compilers and contributors
2. Introduction
3. Defining list of indicators
4. Data collection
5. Indicator classes and weightings
6. Results and Discussion
   1. Summary of results
   2. Database

Summary of results

Data for the various indicators to be used for assessing desertification risk and land management practices for combating desertification have been collected in 1641 field sites corresponding to 15 study sites (Table 3). The main processes and causes identified in the various field sites were soil erosion (including water, tillage and wind erosion), soil salinization, water stress, forest fires, urbanization, and overgrazing. Water erosion was identified as the most important process of land degradation and desertification described in 858 field sites corresponding to the following 9 study sites: Guadalentin Basin Murcia-Spain, Secano Interior-Chile, Boteti Area-Botswana, Santiago Island-Cape Verde, Cointzio catchment-Mexico, Mamora Sehoul-Morocco, Eskisehir-Turkey, Zeuss Koutine-Tunisia, Novij Saratov-Russia, and Crete-Greece. The next more important process of land degradation was tillage erosion described in 283 field sites, and corresponding to the following 4 study sites: Rendina Basin Basilicata-Italy, Boteti Area-Botswana, Loess Plateau-China, and Crete-Greece. Soil salinization was another important degradation process described in 258 field sites, and corresponding to the following 5 study sites: Nestos Basin Maggana-Greece, Boteti Area-Botswana, and Konya Karapinar plain-Turkey, Novij Saratov-Russia, Djanybek-Russia, and Crete-Greece. Water stress was identified as important process in 203 field sites, corresponding to the following 4 study sites: Boteti Area-Botswana, Konya Karapinar plain-Turkey, Novij Saratov-Russia, and Crete-Greece. Overgrazing was defined as important process of land desertification in 140 field sites, corresponding to the following 3 study sites: Boteti Area-Botswana, Konya Karapinar plain-Turkey, and Djanybek-Russia. Forest fires were identified as the main cause of desertification in 85 field sites, corresponding mainly to Mação-Portugal, Cointzio catchment-Mexico, Gois - Portugal study sites and in few cases in the Boteti Area-Botswana site. Finally, urbanization has been described as main cause of desertification in 9 field sites, all of them in the Boteti Area-Botswana site.

Table 3. Distribution of study field sites among the various processes or causes of desertification defined in the various study sites.

*Data have been collected in the same field for two different processes

The various processes and causes identified in the various study field sites were described in areas with a variety of land uses, representative of the dry and Mediterranean climatic conditions. The major land uses described were:

1. Agriculture
2. Pastures
3. Shrubland
4. Forests
5. Mining areas.

In the agricultural areas the main types of vegetation cover were: perennial crops including vines, olives, and almonds; annual crops including cereals, vegetables, and sunflower. In the forested areas the main vegetation cover types were pines, deciduous forests, and evergreen forests. In pastures and shrublands the main vegetation cover types were perennial grasses, annual grasses, and Mediterranean macchia.

The various indicators defined in the various study field sites are separately described in the deliverable 2.1.1 of this Project. Furthermore, the data will be statistically analyzed in WP2.2. Additionally the obtained data of the farm surveys will be statistically analyzed separately for each land use type in order to define: (a) the correlation of the defined indicators to the stage of land degradation (correlation coefficient), (b) the interrelationships between various indicators (analysis of covariance), (c) the effectiveness of each indicator to evaluate the sensitivity to desertification (analysis of variance). Furthermore, a multiple regression analysis will be applied separately for each land use type with dependent variable the desertification risk and independent variables the identified indicators and empirical relations will be defined.