Estimation of soil organic carbon stocks of two cities, New York City and Paris

Abstract

In cities, the strong heterogeneity of soils, added to the lack of standardized assessment methods, serves as a barrier to the estimation of their soil organic carbon content (SOC), soil organic carbon stocks (SOCS; kgC m) and soil organic carbon citywide totals (SOCCT; kgC). Are urban soils, even the subsoils and sealed soils, contributing to the global stock of C? To address this question, the SOCS and SOCCT of two cities, New York City (NYC) and Paris, were compared. In NYC, soil samples were collected with a pedological standardized method to 1 m depth. The bulk density (D) was measured; SOC and SOCS were calculated for 0-30 cm and 30-100 cm depths in open (unsealed) soils and sealed soils. In Paris, the samples were collected for 0-30 cm depth in open soils and sealed soils by different sampling methods. If SOC was measured, D had to be estimated using pedotransfer functions (PTFs) refitted from the literature on NYC data; hence, SOCS was estimated. Globally, SOCS for open soils were not significantly different between both cities (11.3 ± 11.5 kgC m in NYC; 9.9 ± 3.9 kgC m in Paris). Nevertheless, SOCS was lower in sealed soils (2.9 ± 2.6 kgC m in NYC and 3.4 ± 1.2 kgC m in Paris). The SOCCT was similar between both cities for 0-30 cm (3.8 TgC in NYC and 3.5 TgC in Paris) and was also significant for the 30-100 cm layer in NYC (5.8 TgC). A comparison with estimated SOCCT in agricultural and forest soils demonstrated that the city's open soils represent important pools of organic carbon (respectively 110.4% and 44.5% more C in NYC and Paris than in agricultural soils, for 0-30 cm depth). That was mainly observable for the 1 m depth (146.6% more C in NYC than in agricultural soils). The methodology to assess urban SOCS was also discussed.

Effects of Urban Forest Types and Traits on Soil Organic Carbon Stock in Beijing

“…In contrast, green space management in Paris may help to increase SOC stock in open soil [75]. However, researchers of urban forest soil organic carbon need to learn more from the research experience of natural forest soil and carry out more systematic and comprehensive research in the world [76].…”

Urban areas, human health and technosols for the green deal

“…Cambou et al ( 2021 ) consider urban area soil organic carbon stock mainly depends on whether the soil is sealed or not. Carbon entry into sealed soils is practically impossible (Cambou et al, 2021 ), although Cambou et al ( 2018 ) mention the importance of analyzing subsoil organic carbon storage, in urban sealed soils because total amount is relevant. In fact, approximately 69% of carbon storage in a citywide related to greenspace soil, 13% on sealed soil and 18% on vegetation (Edmondson et al, 2012 ).…”

“…Consequently, this paper provides a compilation of their proposals: Strategies to enhance policy, sustainable soil management practices (Cambou et al, 2021 ; Montanarella & Panagos, 2021 ; Tresch et al, 2018a , 2018b ) and direct production processes towards sustainable models (EC, 2020a ). In addition, seems to be a need for addressing the development of globalized regulations for soil protection, for using waste to formulate Technosols, and for standardizing assessment methods (Akande et al, 2019 ; Cambou et al, 2018 ). Authors agree on the requirement of expanding research on analyzing urban soil quality, to assess their level of ecosystem functioning as a service provider (Paradelo et al, 2020 ; Tresch et al, 2018a ), and because additional studies can help to understand links between soils and health (Brevik et al, 2020 ; Fergusson, 2017 ).…”

“…Strategies to enhance policy, sustainable soil management practices (Cambou et al, 2021 ; Montanarella & Panagos, 2021 ; Tresch et al, 2018a , 2018b ) and direct production processes towards sustainable models (EC, 2020a ). In addition, seems to be a need for addressing the development of globalized regulations for soil protection, for using waste to formulate Technosols, and for standardizing assessment methods (Akande et al, 2019 ; Cambou et al, 2018 ).…”

The Impact of Impervious Surface Expansion on Soil Organic Carbon: A Case Study of 0–300 cm Soil Layer in Guangzhou City

“…The effect of impervious surface expansion on soil carbon storage has been studied from two perspectives. Some studies revealed the differences in SOC storage between sealed soils and surrounding greenspace soil at the sample site scale [14,[19][20][21][22][23], and others have used spatially explicit models driven by land cover change and/or other multiple environmental covariates to analyze the total SOC loss and its spatial and/or temporal variability at regional, national and even global scales [24][25][26][27][28]. These models provide a powerful and effective tool for presenting carbon changes in space and time.…”