Quantifying soil physical quality by using indicators and pore volume-function characteristics of the gypsiferous soils in Iraq
2022
Al-Kayssi, A.W.
Despite the fact that indicators of soil physical quality (SPQ) are direct or indirect manifestations of pore volume function, optimal pore volume-function parameters of gypsiferous soils are still to be identified. The study's goals were to: i) to determine the impact of soil gypsum content on the SPQ and pore volume distribution characteristics, ii) develop an optimal pore volume distribution recommendation using the indicators, iii) using indicators and pore volume distributions, evaluate the SPQ of a poly-γ-glutamic acid-amended gypsiferous soil. Using undisturbed soil cores and grab materials from 15 gypsiferous soils, the SPQ indices were determined in the lab. To determine pore volume ranges and water-released curves, the van Genuchten equation was used to fit desorption values using soil cores and grab materials. The best overall SPQ was found in soils with a gypsum content of 135–150 g kg⁻¹, according to the determined indicators, which was applied to determine an optimal pore volume distribution. There were two different types of non-optimal soils. The first group had a gypsum content of 30–123 g kg⁻¹, which was much below “optimal” and had a higher proportion of small pores, whereas the second group had a gypsum content of 164–301 g kg⁻¹, which was generally over “optimal” and had a lower proportion of small pores. The SPQ and maize yield of soils with gypsum content of 30 and 301 g kg⁻¹ were improved by adding poly-γ-glutamic acid. For measuring the physical quality of gypsiferous agricultural soils, the SPQ indicators should be considered in conjunction with optimal pore volume distribution and Dexter “S-value”.
Afficher plus [+] Moins [-]Mots clés AGROVOC
Informations bibliographiques
Cette notice bibliographique a été fournie par National Agricultural Library
Découvrez la collection de ce fournisseur de données dans AGRIS