Contribution des sols à la production de services écosystémiques en milieu urbain – une revue

Les sols fournissent des services à la population humaine, appelés services écosystémiques. En vue de répondre aux problématiques environnementales qui se concentrent en milieu urbain, il est attendu que ces services soient facilement appréhendables par les acteurs de l’aménagement. Cet article propose des définitions claires de termes centraux comme « sol urbain », « sol anthropisé » et « couverture de sol » ; il présente également les caractéristiques bio-physico-chimiques des sols urbains. Des analyses bibliométrique et bibliographique de la littérature scientifique sur les services écosystémiques des sols urbains permettent de positionner la place de ce sujet sur les 20 dernières années et de proposer une liste de ces services. Enfin, une analyse critique des perspectives de développement d’outils d’aide à la décision à l’attention des aménageurs pour la prise en compte des sols urbains à chaque étape de l’aménagement est proposée.Soils, as ecosystems provide services that are also called ecosystem services. In the context of natural resources preservation, urban soils are expected to be multifunctional and to provide high level of ecosystem services (e.g. vegetation support, building support, flood control). Therefore, there is a need for urban planners to take into account the urban soil potentials in urban project development. This article proposes definitions of such crucial terms such as “urban soil”, “anthropized soil” and “sol cover”; it also presents the main bio-physical-chemical characteristics of urban soils. A bibliometric analysis has been conducted to describe the position of ecosystem services provided by urban soils within the frame of actual research. A list and a description of the ecosystem services provided by urban soils is proposed. Finally, this article offers prospects for the development of decision-making tools for planners to encourage them to take into account soil ecosystem at each stage of planning

Fonctionnement et évolution pédogénétiques de Technosols issus d'un procédé de construction de sol

La restauration des fonctions des sols est une étape clé de la requalification des sites dégradés par les activités humaines. Ces opérations nécessitent de disposer de procédés de remise en état du couvert pédologique favorisant la résilience écologique. Ils génèrent de nouveaux sols dont il faut prévoir l évolution. Notre objectif est de caractériser le fonctionnement et la pédogenèse de sols construits à l aide d un nouveau procédé fondé sur la formulation de déchets et sous-produits (terre industrielle traitée, sous-produit papetier, compost). Dans ce but, des colonnes en laboratoire ainsi que des parcelles lysimétriques in situ ont été mises en place. Des paramètres descriptifs des fonctionnalités et de la pédogenèse des sols construits ont été mesurés. Les résultats ont montré que les matériaux parents présentent des propriétés aptes à remplir des fonctions comme la fourniture d éléments ou la rétention en eau. Les sols construits remplissent les rôles de support de végétation, d échange/filtre et de support de la biodiversité comme des sols naturels. Les premiers stades de leur évolution pédogénétique se caractérisent par leur intensité, leur rapidité et leur caractère non habituel (e.g. dissolution conjointe de gypse et de calcite). La prospective sur l évolution des sols construits démontre que, de Technosols, ils évoluent vers des types de sols analogues aux sols naturels. Ce cheminement nous conduit à proposer une évolution de la classification des sols très anthropisés sur des critères génétiques. Enfin, les bases de la modélisation de la pédogenèse des sols très anthropisés sont posées ainsi que celles d un outil d aide à la décision pour le génie pédologiqueHuman activities induce growing impacts on soils. This has produced derelict lands that need thorough reclamation to minimize their negative effect on the environment. A better knowledge and control of the evolution of highly anthropized soils is needed in order to achieve a sustainable management of these sites. This work emphasizes on both the development of a process of soil construction with wastes and by-products (paper sludge, treated industrial soil, compost) and the study of the functioning and pedogenic evolution of the constructed soils. The project relies on both in situ pilot scale application and lab-scale experiments. The characterization of the parent materials and their compounding highlighted their properties and their originalities compared to geological or pedological materials. The study of the functioning of constructed soils demonstrated that they could fulfil the soil basic functions. In this way, the process has been able to achieve the reclamation of the pedological cover and initiate the ecological resilience. The nature, the intensity and the kinetics of the pedogenic processes have been identified. It appeared that the reactions were very fast and that they sometimes strongly differ from the natural local pedo-climate (e.g. dissolution of gypsum, amorphous silica). We suggest that they will spontanuously evolve to analogous natural form of soils. Our results are confronted with the present classification of the Technosols and some propositions are made in favour of a more genetic-oriented way. Some thoughts about the modelling of the pedogenesis of very anthropized soils are proposed. At last, this work evocates the basis for the development of a decision tool for the pedo-engineering approach.NANCY/VANDOEUVRE-INPL (545472102) / SudocNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF

Contribution des sols à la production de services écosystémiques en milieu urbain – une revue

Les sols fournissent des services à la population humaine, appelés services écosystémiques. En vue de répondre aux problématiques environnementales qui se concentrent en milieu urbain, il est attendu que ces services soient facilement appréhendables par les acteurs de l’aménagement. Cet article propose des définitions claires de termes centraux comme « sol urbain », « sol anthropisé » et « couverture de sol » ; il présente également les caractéristiques bio-physico-chimiques des sols urbains. Des analyses bibliométrique et bibliographique de la littérature scientifique sur les services écosystémiques des sols urbains permettent de positionner la place de ce sujet sur les 20 dernières années et de proposer une liste de ces services. Enfin, une analyse critique des perspectives de développement d’outils d’aide à la décision à l’attention des aménageurs pour la prise en compte des sols urbains à chaque étape de l’aménagement est proposée.Soils, as ecosystems provide services that are also called ecosystem services. In the context of natural resources preservation, urban soils are expected to be multifunctional and to provide high level of ecosystem services ( e.g. vegetation support, building support, flood control). Therefore, there is a need for urban planners to take into account the urban soil potentials in urban project development. This article proposes definitions of such crucial terms such as “urban soil”, “anthropized soil” and “sol cover”; it also presents the main bio-physical-chemical characteristics of urban soils. A bibliometric analysis has been conducted to describe the position of ecosystem services provided by urban soils within the frame of actual research. A list and a description of the ecosystem services provided by urban soils is proposed. Finally, this article offers prospects for the development of decision-making tools for planners to encourage them to take into account soil ecosystem at each stage of planning

Selection of soil health indicators for modelling soil functions to promote smart urban planning

International audienceThe contribution of soil health to global health receives a growing interest, especially in urban environment. Therefore, there is a true need to develop methods to evaluate ecological functions provided by urban soils in order to promote smart urban planning. This work aims first at identifying relevant soil indicators based either on in situ description, in situ measurement or lab analysis. Then, 9 soil functions and sub-functions were selected to meet the main expectations regarding soil health in urban contexts. A crucial step of the present research was then to select adequate indicators for each soil function and then to create adapted reference frameworks; they were in the form of 4 classes with scores ranging from 0 to 3. All the reference frameworks were developed to evaluate soil indicators in order to score soil functions, either by using existing scientific or technical standards or references or based on the expertise of the co-authors. Our model was later tested on an original database of 109 different urban soils located in 7 cities of Western Europe and under various land uses. The scores calculated for 8 soil functions of 109 soils followed a Gaussian distribution. The scoring successfully expressed the strong contrasts between the various soils; the lowest scores were calculated for sealed soils and soils located in urban brownfields, whereas the highest were found for soils located in city parks or urban agriculture. Despite requiring a soil expertise, the proposed approach is easy to implement and could help reveal their true potential of urban soils in order to promote smart urban planning and enhance their contribution to global health

From waste to fertile technosol - The circular approach of the French research prject SITERRE

Sustainable Urban Agricultures : Vector for the Ecological Transition, TOULOUSE, FRANCE, 06-/06/2017 - 09/06/2017Today, 50 % of the world population live in urban areas with an increasing evolution for the next decade. The city is an anthropological environment created by the man and for the man. For a very long time, the city was built to protect humans from wild animals. Nowadays, the city is a workplace, a hosting place, an entertainment place, a place of life in which the people must find all the necessary elements for his balance. The modern city presents a 'linear metabolism' that needs inputs (food, industrial products, raw materials) to develop all its activities with a lot of movement, circulation and transformation of material resources. A the end of the metabolize chain, the city produces waste that flow out of the urban system involving depletion of natural resources, pollution and toxic environments. Thus in the urban context, the balance, necessary for human physical and mental health, is a hot topic that must be deal with the environment and the nature. To preserve its viability, the urban system must evolve rapidly to a 'circular metabolism' by decreasing input consumption and by limiting economic and ecological costs for the transportation, treatment and landfill of waste materials