A laboratory study to disentangle hydrological, mechanical and structural mechanisms of soil stabilisation by plant mucilage between eroding and depositional zones of a slope

Zhong, X. L., Li, J. T., Naveed, Muhammad, Raffan, A. and Hallett, P. D. (2020) A laboratory study to disentangle hydrological, mechanical and structural mechanisms of soil stabilisation by plant mucilage between eroding and depositional zones of a slope. European Journal of Soil Science. ISSN 1351-0754

[img] PDF
Naveed_etal_EJSS_2020_A_laboratory_study_to_disentangle_hydrological_mechanical_and_structural_mechanisms_of_soil_stabilisation_by_plant_mucilage_between_eroding_and_depositional_zones_of_a_slope.pdf - Accepted Version
Restricted to Repository staff only until 3 March 2021.

Download (2MB)

Abstract

Biological exudates, such as plant mucilage, can greatly stabilise soils but as the mechanical and hydrological drivers depend much on soil particle size composition, eroding and depositional areas of a slope may respond differently. Soils from an eroded midslope and a depositional footslope in an arable farm were amended with chia (Salvia hispanica) seed mucilage at concentrations of 0 g C kg−1, 0.46 g C kg−1 and 2.3 g C kg−1 mucilage, formed into cores, and then imparted with wetting and drying (WD) cycles. Mucilage increased the stability of these inherently stable soils from 80% to >98% water stable macroaggregates at 0WD cycles regardless of slope position. Aggregate stability was maintained after 5WD cycles by mucilage, whereas the stability of unamended soil dropped by 66.7% in the footslope and 30.1% in the midslope compared with 0 WD. Underlying physical stability properties were measured by tensile strength and penetration resistance for mechanical, water sorptivity and repellency for hydrological, and micro‐, meso‐, macro‐ and total porosity for structural properties. Almost every soil physical property measured changed less with WD cycles if mucilage was present. Compared to unamended soil, 2.3 g C kg−1 mucilage amendment decreased water sorptivity from 0.289 mm s‐1/2 to 0.122 mm s‐1/2 in the midslope and 0.230 mm s‐1/2 to 0.182 mm s‐1/2 in the footslope after 5 WD cycles. Aggregate stability, total porosity and water sorptivity were correlated. In the midslope, hydrology and penetration resistance were affected most, likely driven by mucilage deposition in the macropores of this more coarsely textured soil. In the footslope, the greater impact of mucilage on tensile strength was likely driven by buffering of macroporosity formation by WD cycles in this finer textured soil.

Item Type: Article
Additional Information: This is the peer reviewed version of the following article: [Zhong, X.L., Li, J.T., Naveed, M., Raffan, A. and Hallett, P.D. (2020), A laboratory study to disentangle hydrological, mechanical and structural mechanisms of soil stabilisation by plant mucilage between eroding and depositional zones of a slope. Eur J Soil Sci. Accepted Author Manuscript], which has been published in final form at https://doi.org/10.1111/ejss.12955. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
Uncontrolled Keywords: hydrological, mechanical, plant mucilage, soil stability, slope, structural
Subjects: Construction and engineering
Depositing User: Camille Regnault
Date Deposited: 18 Mar 2020 13:56
Last Modified: 18 Mar 2020 13:56
URI: http://repository.uwl.ac.uk/id/eprint/6822

Actions (login required)

View Item View Item

Menu