Editorial Humusica 2

Humusica 2 is dedicated to three different groups of humipedons:a) submersed in sweet or salt waters;b) atypical and made by aerobic and anaerobic microorganisms, fungi, algae, lichens, musses, roots, and degrading wood specific organisms;c) Anthropogenic Techno (man made) and Agro (modi fied for agricultural purposes).Articles 9, 10, 11 and 12 correspond to keys of classification of soil horizons and humus systems of wetlands, peats and sea-sides. The pre-sentation of Humusica 2 follows the same scheme used for Humusica 1 “Terrestrial humipedons ”: a short part of vocabulary, an illustrated list ofdiagnostic horizons and key of classifications individuating series of diagnostic horizons.Article 13 deals with the initial phases of soil construction, through pioneer humus systems, from thin Crusto to thicker Bryo, Rhizo or Lignohumus systems in terrestrial ecosystems, or Archaeo and Anaero of submersed ecosystems. It corresponds to a first attempt of classification, with theaim to dispose along a hypothetic evolutionary line, humipedons of increasing complexity. The target was also to provide a complete “living skin” toplanet Earth, by looking at poorly investigated mountain or desert areas and rivers or sea beds.Articles 14 was written by soil scientists in order to point out the conceptual difference between anthropogenic soils and humipedons. Threepoints of view (World Reference Base; Soil taxonomy; Humus systematics) are illustrated, explaining the not availability of a single standardreference for global soil classification.Natural and anthropogenic soil structures are compared in article 15. This allowed to distribute the agricultural soils along a gradient ofincreasing distance (in term of quality of soil aggregates) of them from corresponding original natural soil structures.Some examples of Techno humus systems are illustrated in article 16; it finishes with the study of the biological activity in South African minetailings.Articles 17, 18 and 19 are dedicated to anthropogenic humus systems and agriculture. These articles support a biological/ecological concept ofsoil and sustainable agricultural strategies, to preserve organic matter and soil organisms. Instead of focusing on soil properties and quantity ofproduced food, we preferred to show the relationship between soil and food quality (article 17). The principal aim of article 18 was to give anoverview of existing soil- and humus system maps at global level. This allowed to evidence that agriculture and grazing activities are established onparticular soils and humus systems. Finally, in article 19, we reconsidered the concept of soil proposed at the beginning of the Special Issue(Humusica 1, article 1), based on historical scientific field experiences by Masanobu Fukuoka, Marcel Bouché, Jeff Lowenfels and Allan Savory,suggesting/confirming that: a) soil functionality and carbon storage strongly depend on the biological soil structure; b) natural processes of soil-plantcoevolution are still poorly understood; c) animal populations interacting out and in the soil of grasslands are necessary to restore and maintain theseprecious ecosystems; d) drainage and cultivation of ancient wetlands destroy the original functioning and diminish the carbon storage in these areas;e) we should take advantage of the natural soil biological machineries (humus systems), which are specialised and ecologically connected to theenvironment; in this perspective, Mull (crops) and Rhizo (pasture) humus systems are crucial means for mitigating the consequences of climatechange on the global carbon dynamic.