Ranking of wetting–drying, plant, and fauna factors involved in the structure dynamics of a young constructed Technosol

Abstract

Purpose Dynamical in situ observation of biological and climatic structuring factors involved in pedogenesis has not previously been possible in a way that would consider the early stages of pedogenesis. If studies have explored the effect of pedogenetic factors on soil structure, none have succeeded in ranking them in view of the intensity of their effects. We propose a novel approach for describing the aggregation process for a constructed Technosol obtained from a process of pedological engineering. Materials and methods We focus on agents including plants, macrofauna, and water, and we use (i) a dynamic in situ observation and (ii) the quantification of the evolution of selected descriptors of pores and aggregates. They are quantified from highresolution images obtained with the Soilinsight® device. Associating those images with each other, movies of interactions between soil and organisms over a 14-month non-destructive soil evolution experiment are made. Results and discussion Agents influencing aggregation-plant roots, earthworms, and water-can be ranked according to their impact on soil structure. During the studied period of evolution, wetting-drying cycles are the first to operate. The intensity of their action on soil structure is dominant at the very first stages of pedogenesis. Despite this ranking of agents, over the long term, plants and earthworms have a more intense effect on soil structure than wetting-drying cycles. Conclusions The method applied to observe and quantify soil structure dynamics is thus proposed as a helpful approach to modeling other processes involved in soil functioning and evolution in relation to their ability to fulfill ecosystem services.

Using constructed soils for green infrastructure – challenges and limitations

“…For example, in arid climates where the risk of hydromorphy is low, one can add a higher concentration of organic matter in subsurface deep horizons than in surface horizons so that organic matter will be protected from oxidation and will improve the water availability surrounding the root system. Establishing an active plant community as an internal source of organic matter and as a driver of multiple biotic and abiotic interactions is also important (Deeb et al, 2016b;Jangorzo et al, 2018Jangorzo et al, , 2014Pey et al, 2013aPey et al, , 2014. A 3-year monitoring plan of carbon balance in Technosols from Moscow, Russia, showed substantial carbon release during the first months after construction, which was almost completely fixated in the next 3 years by carbon input from the root biomass growth (Shchepeleva et al, 2017(Shchepeleva et al, , 2019.…”

“…For example, Séré et al (2008) highlighted the importance of shaping a functional soil for restoring abandoned land by focusing on three main soil functions, namely water buffering and transformation, biomass production, and trace element cycles. These authors noted additional functions such as microbial activity related to the nitrogen cycle (Hafeez et al, 2012a, b), improving soil structure (Jangorzo et al, 2018(Jangorzo et al, , 2013(Jangorzo et al, , 2014, and macrofauna activity related to nutrient cycling (Pey et al, 2013a(Pey et al, , 2014. The French Scientific Interest Group (GISFI; http://gisfi.univ-lorraine.fr/ fr/, last access: 4 September 2020) conducted the first largescale (100 m 3 ) field experiment using waste comparing two types of constructed Technosols for the ecological reclamation of abandoned land (Fig.…”

Constructed Technosols are key to the sustainable development of urban green infrastructure

“…For example, in arid climates where the risk of hydromorphy is low, one can add a higher concentration of organic matter in subsurface deep horizons than in surface horizons, so that organic matter will be protected from oxidation and will improve water availability surrounding root system. Establishing an active plant community as an internal source of organic matter and as a driver of multiple biotic and abiotic interactions is also important (Deeb et al, 2016b;Jangorzo et al, 2018Jangorzo et al, , 2014Pey et al, 2013aPey et al, , 2014. A threeyear monitoring plan of carbon balance in Technosols from Moscow, Russia showed substantial carbon release during the first months after construction, which was almost completely fixated in the next three years by carbon input from the root biomass growth (Shchepeleva et al, 2017;.…”

“…For example, Séré et al (2008) highlighted the importance of shaping a functional soil to restore abandoned land, focusing on three main soil functions: water buffering and transformation, biomass production, and trace element cycles. These authors noted additional functions such as microbial activity related to the nitrogen cycle (Hafeez et al, 2012a(Hafeez et al, , 2012b, improving soil structure (Jangorzo et al, 2018(Jangorzo et al, , 2013(Jangorzo et al, , 2014 and macrofauna activity related to nutrient cycling (Pey et al, 2013a(Pey et al, , 2014. The French Scientific Interest Group (GISFI) (http://www.gisfi.prd.fr) conducted the first large-scale (100 m 3 ) field experiment using waste comparing two types of constructed Technosols for ecological reclamation of abandoned land (Fig.…”