A study of the main factors influencing soil organic carbon stock distribution in urban soils, at French scale - Institut Agro Rennes-Angers Accéder directement au contenu
Communication Dans Un Congrès Année : 2017

A study of the main factors influencing soil organic carbon stock distribution in urban soils, at French scale

Résumé

Soils are the largest pool of terrestrial organic carbon. They can behave as a sink or a source of atmospheric CO2 (Jacobson et al., 2000). The prediction of climate change consequences on ecosystems depends partly on the better understanding of the distribution and control of soil organic carbon (SOC) content. Artificialized areas represent nearly 3% of the World territory (9.3% in France), and by 2050 the proportion of the urban population is expected to reach 66% worldwide (Liu et al., 2014; Service de la Statistique et de la Prospective, 2015; United Nations et al., 2014). However, available data to assess whether urbanization leads to an increase or decrease of SOC and which factors explain the most the SOC distribution in these very heterogeneous soils, are extremely scarce. Hence, the effective role of urban soils in carbon sequestration and greenhouse gas balance is unknown and generally underestimated. Our hypothesis is that the anthropic factors (i.e. land use types and management) and vegetation cover mostly explain SOC cartography in urban soils, at a territory scale. The first objective is to link the urban soil use, management and vegetation cover to their soil organic carbon stock (SSOC), at French territory scale. The second objective is to determine whether these factors explain the most SSOC distribution in urban soils, compared to extrinsic natural factors and soil property variables (e.g., climate, nitrogen content, carbonate content, clay content), at French territory scale. This work is based on a systematic data collection from different organizations (e.g., research institutes and associated project leaders, cities and urban agglomerations), over the French territory, which have accepted to share their data for this study. More than 10,000 data, displaying environmental characteristics, SOC contents and other soil properties (e.g., cation exchange capacity, pH, nitrogen and carbonate contents and soil texture), were collected. After SSOC estimation, a statistical treatment was conducted to characterize the different types of urban soils, according to their SSOC and the main factors explaining SSOC distribution. We have tested the effect of extrinsic parameters such as climate, urban land use (a classification of 14 types of uses adapted from Micand and Larramendy, 2014), vegetation cover (herbaceous, horticultural massive, tree or vegetation mix covers), management frequency and age of the site. The effects of the available intrinsic soil properties were also tested. The effects of the anthropic factors (land use, age of site, and type of vegetation) on SSOC were the most significant and allowed to regroup the urban soils in three different categories, according to their SSOC: i) sealed soils; ii) open vegetated and strongly managed soils; iii) open vegetated and near-natural soils. The climate had also a significant effect on SSOC distribution as well as the following soil properties: nitrogen and clay contents. According to these results, it will be necessary to focus on the three urban soil categories in different cities of France, under contrasted climatic conditions, in order to understand the SOC dynamics, at the soil profile scale.
Fichier non déposé

Dates et versions

hal-02516009 , version 1 (23-03-2020)

Identifiants

  • HAL Id : hal-02516009 , version 1

Citer

Aurelie Cambou, Laure Vidal Beaudet, Patrice Cannavo, Christophe Schwartz. A study of the main factors influencing soil organic carbon stock distribution in urban soils, at French scale. SUITMA 9 The 9th International conference of Soils of Urban, Industrial, Traffic, Mining and military Areas, Jun 2017, Moscou, Russia. pp.150-151. ⟨hal-02516009⟩
94 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More