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Soil degradation and desertification processes in the Mediterranean basin reflect the interplay between environmental and socioeconomic drivers. An approach to evaluate comparatively the multiple relationships between biophysical variables and socioeconomic factors is illustrated in the present study using the data collected from 586 field sites located in five Mediterranean areas (Spain, Greece, Turkey, Tunisia and Morocco). A total of 47 variables were chosen to illustrate land-use, farm characteristics, population pressure, tourism development, rainfall regime, water availability, soil properties and vegetation cover, among others. A data mining approach incorporating non-parametric inference, principal component analysis and hierarchical clustering was developed to identify candidate syndromes of soil degradation and desertification risk. While field sites in the same study area showed a substantial similarity, the multivariate relationship among variables diverged among study areas. Data mining techniques proved to be a practical tool to identify spatial determinants of soil degradation and desertification risk. Our findings identify the contrasting spatial patterns for biophysical and socioeconomic variables, in turn associated with different responses to land degradation.

The need for reliable estimates of soil loss under different land management practices (LMPs) is becoming imperative in the Mediterranean basin to inform decisions on more effective strategies for land management. The effect of LMPs on soil erosion and land degradation has been investigated using experiments from November 2008 to November 2011 in an olive grove in central Crete (Greece). The study area was on sloping land with soils formed on marl deposits which are vulnerable to desertification because of surface runoff and tillage. The experimental design included three treatments with two replicates (3 × 5 m experimental plots) corresponding to the following LMPs: (i) no tillage–no herbicide application, (ii) no tillage–herbicide application and (iii) ploughing to 20 cm perpendicular to the contours. The following variables were monitored: surface water runoff, sediment loss, soil temperature at 10 cm, soil moisture content at depths of 20 and 50 cm, as well as selected climatic variables. The results show that the no tillage–no herbicide management practice gave the lowest sediment loss (1.44–4.78 g/m2/yr), the lowest water runoff (1.8–11.5 mm/yr), the greatest amount of water stored in the soil, the lowest soil temperature and the lowest desertification risk compared with the other treatments. Tillage resulted in the greatest sediment loss (13.6–39.2 g/m2/yr) and surface runoff (16.5–65.0 mm/yr), and an intermediate amount of water stored in the soil. In addition, this treatment led to the loss of soil thickness of 3.7 mm/yr because of ploughing. The results demonstrate the high risk of desertification in the investigated region and the methodology can be used in other Mediterranean areas as an assessment framework for evaluating land degradation and the impact of land management on soil erosion.

This study investigates the relationship between fine resolution, local-scale biophysical and socioeconomic contexts within which land degradation occurs, and the human responses to it. The research draws on experimental data collected under different territorial and socioeconomic conditions at 586 field sites in five Mediterranean countries (Spain, Greece, Turkey, Tunisia and Morocco). We assess the level of desertification risk under various land management practices (terracing, grazing control, prevention of wildland fires, soil erosion control measures, soil water conservation measures, sustainable farming practices, land protection measures and financial subsidies) taken as possible responses to land degradation. A data mining approach, incorporating principal component analysis, non-parametric correlations, multiple regression and canonical analysis, was developed to identify the spatial relationship between land management conditions, the socioeconomic and environmental context (described using 40 biophysical and socioeconomic indicators) and desertification risk. Our analysis identified a number of distinct relationships between the level of desertification experienced and the underlying socioeconomic context, suggesting that the effectiveness of responses to land degradation is strictly dependent on the local biophysical and socioeconomic context. Assessing the latent relationship between land management practices and the biophysical/socioeconomic attributes characterizing areas exposed to different levels of desertification risk proved to be an indirect measure of the effectiveness of field actions contrasting land degradation.

This study investigates the socio-ecological system dominated by pasture land in Asteroussia Mountains (Crete, Greece) between 1950 and 2010 with the aim to identify changes in the most relevant system's attributes, as a contribution to the study of land degradation from the resilience perspective. The analysis of 10 system indicators identifies two time periods (1950 - mid 1980s and mid 1980s - 2010) characterized by distinct relations between system's components. The grazing system was sustainable in the former time period being satisfactorily managed with moderately-low soil erosion rates despite adverse soil, topographic and climate conditions. Larger land patches have experienced better system's performance than smaller patches. The latter time interval was characterized by landscape fragmentation which has impacted negatively the stability of the overall system. A continuous growth in livestock density was observed in the study period determining high soil erosion rates, loss in plant productivity and a general over-exploitation of natural resources. A significant increase in desertification risk and a parallel decrease of ecological resilience were observed in the last time interval. The contrasting spatial patterns of system's indicators - possibly associated with different responses to land degradation - can be considered in the design of mitigation strategies addressing climate change and socioeconomic vulnerability of Mediterranean pasture land.

The experiment described in this paper compared the effects of two systems for labeling recycled water on potential consumers' intention to use this resource; the current identifying symbol used worldwide (purple color for pipes, containers, and tanks) and a new, empirically derived and validated set of symbols that provide specific information on water quality and positive comparative information. In total, 807 face-to-face surveys were carried out. Subjects were asked to rate their intentions for using different qualities of recycled water for commercial agriculture as well as for using products and facilities irrigated with recycled water, either in the presence of the established symbol or the new, empirically derived symbols. Potential consumers' self-reported intentions to use recycled water were reliably higher in the presence of empirically derived symbols with positive comparative information than in the presence of the conventional identification symbol. This program of research provides a model for the application of principles of behavioral psychology to enhance the consumer acceptance of technological advances that preserve natural resources and protect ecosystems.

The abandonment of land is a global problem with environmental and socioeconomic implications. An approach to assess the relationship between land abandonment and a large set of indicators was illustrated in the present study by using data collected in the framework of the European Union DESIRE research project from 808 field sites located in 10 study sites in the Mediterranean region, Eastern Europe, Latin America, Africa and Asia. A total of 48 indicators provided information for biophysical conditions and socioeconomic characteristics measured at the plot level. The selected indicators refer to farm characteristics (family status, land tenure, present and previous types of land-use, soil depth, slope gradient, tillage operations) and to site-specific characteristics including annual rainfall, rainfall seasonality and water availability. Classes were designated for each indicator and a sensitivity score was assigned to each class based on existing research or empirically assessing the importance of each indicator to the land abandonment issue. Questionnaires for each process of land degradation were prepared and data were collected at field site level in collaboration with land users. Based on correlation statistics and multivariate analyses more than ten indicators out of 48 resulted as significant in affecting land abandonment in the studied field sites. Among them, the most important were rainfall seasonality, elderly index, land fragmentation, farm size, selected soil properties, and the level of policy implementation. Results contribute to the development of appropriate tools for assessing the effectiveness of land management practices for contrasting land abandonment.

The impact of land management practices on soil erosion and land degradation was assessed during three consecutive years (December 2008–November 2011) in a rural area sensitive to desertification (Crete, Greece). The area is characterized by soils formed on flysch parent material, dry sub-humid climate with water deficit concentrated in summer, and frequent drought episodes. Precipitation, water runoff, sediment loss, soil moisture, air and soil temperature, and plant cover were recorded at two sites experiencing overgrazing and sustainable grazing. Sustainable grazing was associated with lower water runoff, reduced sediment loss and lower soil temperature than overgrazing. Plant cover protected soils from water erosion more effectively in the “sustainable grazing” plot than in the “overgrazing” plot. The study identifies overgrazing as a driver of land degradation in southern Europe and points out the contribution of sustainable management of pastoral landscapes in the mitigation of desertification risk.

Land degradation is a complex process resulting from the permanent interaction between physical and human factors. The effect of changes in land-use and land management on soil erosion and desertification risk has been studied in Messara Valley (Crete, Greece) over the last six decades (1950–2010). Vegetation cover and land-use have been analyzed using representative aerial photographs and ortho-photomaps for representative dates. Soil attributes have been described in a semi-detailed survey in 2010. Soil erosion rates and desertification risk have been assessed for each period using the PESERA and TERON models and the MEDALUS methodology, respectively. Based on distinct socio-ecological characteristics of the area three major time intervals have been identified. Cereals extensively cultivated during the first time interval were progressively replaced by olive plantations and vineyards in the following periods. Soil erosion due to water runoff was important especially in the olive transition period, declining in the olive subsidy period. However, tillage erosion became an important degradation process especially in the olive subsidy period due to mechanization of the agriculture determining soil losses ranging from 0.5 to 30 cm in sloping areas. Desertification risk due to soil erosion and land characteristics has significantly increased during the olive subsidy period.

Fat mimetics, namely Raftiline, Simplesse, C*deLight and polydextrose, diluted in water to give a gel with 200 g kg−1 concentration, were used for partial fat replacement and polyols, namely lactitol, sorbitol and maltitol, for sugar replacement in low-fat, sugar-free cookies. Raftiline, Simplesse or C*deLight combined with lactitol or sorbitol in 35% fat-reduced, sugar-free cookies resulted in products with hardness and brittleness comparable to those of the control. Polydextrose as fat mimetic and maltitol as sugar substitute resulted in very hard and brittle products. Further fat replacement to 50% was achieved using Raftiline, Simplesse or C*deLight combined with a blend of lactitol and sorbitol; however, the final products were hard, brittle and did not expand properly after baking. Cookies prepared with Simplesse had the least acceptable flavour, while cookies prepared with C*deLight were rated as the most acceptable by a sensory panel. The textural properties were improved by either decreasing the amount of alternative sweetener or increasing the concentration of fat mimetic in the gel which was added to the cookies. All fat-reduced, sugar-free cookies prepared in this study had higher values of moisture content and water activity than the control, but these values were below the upper limit that affects cookie shelf-life. © 2002 Society of Chemical Industry

International audience; An approach to derive relationships for defining land degradation and desertification risk and developing appropriate tools for assessing the effectiveness of the various land management practices using indicators is presented in the present paper. In order to investigate which indicators are most effective in assessing the level of desertification risk, a total of 70 candidate indicators was selected providing information for the biophysical environment , socioeconomic conditions, and land management characteristics. The indicators were defined in 1,672 field sites located in 17 study areas in the Mediterranean region, Eastern Europe, Latin America, Africa, and Asia. Based on an existing geo-referenced database, classes were designated for each indicator and a sensitivity score todesertification was assigned to each class based on existing research. The obtained data were analyzed for the various processes of land degradation at farm level. The derived methodology was assessed using independent indicators, such as the measured soil erosion rate, and the organic matter content of the soil. Based on regression analyses, the collected indicator set can be reduced to a number of effective indicators ranging from 8 to 17 in the various processes of land degradation. Among the most important indicators identified as affecting land degradation and desertification risk were rain seasonality, slope gradient,plant cover, rate of land abandonment, land-use intensity, and the level of policy implementation.