Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

222.2 --- Genesis

Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

soil chemicophysical properties --- soil chemicophysical properties --- Soil biology --- Soil biology --- soil genesis --- soil genesis --- ecology --- ecology

Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

The natural background levels of metallic trace elements (MTEs) in cultivated soils should be known in order (i) to understand the processes in which MTEs are involved and (ii) settle a reference system dedicated to the appraisal of agricultural practices, to the detection of contaminations, or to the time-course follow-up of regional values. A methodological framework has thus been set up to evaluate the importance of natural driving factors, the pedogeochemical background, of the spatial distribution of MTEs in soils and also to compare the current levels of MTEs content in agricultural soils from the Loamy Region with natural values. As main results from the study of parent materials, (i) lithological units are now characterized with element content signatures, (ii) the prominent part of clay, total iron, and total aluminium contents as driving factors of the content in MTEs has been measured, and (iii) the geographical homogeneity as well as the absence of spatial continuity of the cover loessic parent material have been showed up. The relations between MTEs and driving variables have been confirmed through the study of the influences of pedogenesis factors on the vertical and lateral differenciations of MTEs content in soils. It was also demonstrated that taking into account the natural volumes of soils when sampling facilitates the interpretation of the results and allows finer estimations of the MTEs content, even in homogeneous context. The reference values about natural and usual content in MTEs for various soil horizons that are proposed reveal a relatively weak level of man-made contamination in the Loamy Region. It has also been shown that a regional reference system dedicated to the detection of local contaminations gains in relevance as it integers ancillary datas as well as the local specificities of small natural regions. The spatial variability of MTEs content has been evaluated through various cartographic approaches which led to the conclusion that the Soil Map of Belgium is an extremely worthy document for geochemical mapping.

Cultivated land --- Cultivated land --- Silty soils --- Silty soils --- Metallic elements --- Metallic elements --- Geographical distribution --- Geographical distribution --- soil genesis --- soil genesis --- cartography --- cartography --- Belgium --- Belgium

Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

Prodigal son (Parable) --- Jacob --- Bible. --- Relation to Luke. --- Criticism, interpretation, etc. --- Relation to Genesis.

Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

In this work, the principles and methods of geomorphopedology used as landscape comprehension "keys", have been evaluated and implemented in order to develop and put forward an integrated cartography of the steppic environment. The observations and surveys inherent to this method highlight the relations between the landscape forms, superficial formations, correlated soils, vegetation, and farming systems developed by the local populations. This approach has proved to be extremely well suited to understanding the soil genesis and in particular the shape of the associated calcareous accumulations in function of space and in time factors. The findings of specific analyses carried out using methods and techniques of several disciplines (mineralogy, micromorphology, palynology and C14 dating) throw light on the desertification process in space and time. For instance, analysis of pollen samples on soils of terraces from the Holocene (old and recent Rharbian) to the present time, have shown the clear dominance of a tree vegetation during the Neolithic period and its gradual decline. This implies that a progressive aridification of the climate has occurred since the Neolithic period (old Rharbian). This can be considered as a primary cause of the degradation of the steppic environment, making it more sensitive to the impact of anthropic factors.

Steppes --- Geomorphology --- Soil sciences --- soil genesis --- land use --- Landscape --- Desertification. --- Desertification --- Palynology --- Climatology --- human population --- Environmental impact --- Algeria --- Algeria