Total, cold and hot water extractable organic carbon in soil profile: impact of land-use change

Abstract

The content of labile, especially water extractable organic carbon (WEOC) is a sensible indicator of soil organic matter quality. The main objectives of this study were: i) to investigate the profile changes of cold and hot water extractable organic carbon in forest and arable soils; ii) to evaluate the correlation between these labile fractions of soil organic matter and total organic carbon content. The experiments were carried out on a Gleyic Albeluvisol (ABg) in the upper part of Dniester basin, Western Ukraine. The soil samples were taken from 50-cm depth soil profile with 5-cm step. Total organic carbon (TOC), cold water extractable organic carbon (CWEOC) and hot water extractable organic carbon (HWEOC) contents in soil were determined as well as pH (H 2 O) and electrical conductivity of soil:water suspensions. The results of this study showed that in 0-50 cm layer of arable soil TOC content decreased by 32%, CWEOC -by 23% and HWEOC -by 74% compared to forest soil that confirmed a high informative role of HWEOC fraction. The profile changes of WEOC percentage were analysed. They also show that HWEOC is much more informative indicator of soil organic matter quality than CWEOC. The most prominent changes of soil chemical properties, TOC, CWEOC and HWEOC contents in response to deforestation were observed in the top 5-cm soil layer. We suggested this thin soil layer to be defined as soil stress-sensitive zone.

Comparison of the Effects of Different Crop Production Systems on Soil Physico-Chemical Properties and Microbial Activity under Winter Wheat

“…In tilled soil under both crop production systems the assessed quantities of CWEC in all studied layers represented similar level and were two times higher as compared with non-tilled ( Figure 7). Our results are in accordance with the ones published earlier by Hamkalo and Bedernichek [30]. They also indicated that quantities of HWEC and CWEC were significantly lower in arable than in uncultivated soils.…”

“…In tilled soil under both crop production systems the assessed quantities of CWEC in all studied layers represented similar level and were two times higher as compared with non-tilled ( Figure 7). Our results are in accordance with the ones published earlier by Hamkalo and Bedernichek [30]. They The highest quantity of HWEC fraction was assessed in the surface soil depth 0-5 cm under permanent grass 1387.2 µg g −1 d.w. of soil, on average, which was almost three times the quantity obtained in soil under the CON system.…”

Suminė ir labilioji anglis dirvožemyje tręšiant šunažolę mineralinėmis trąšomis ir biodujų gamybos šalutiniu produktu

“…Pastaruoju metu vis daugiau kalbama ir tyrinėja ma, kaip biodujų gamybos procese likusios atliekos, panaudotos žemės ūkyje, tampa organinės anglies šaltiniu ir prisideda prie dirvožemių kokybės geri nimo. Vis daugiau dėmesio skiriama labiliajai dir vožemio angliai (Rao et al, 2013;Hamkalo et al, 2014), kuri pripažįstama kaip gero dirvožemio in dikatorius (Strosser, 2010;Dinesh et al, 2015). La biliosios anglies šaltiniai, nustatyti chemiškai frak cionuojant, pripažįstami kaip jautrūs dirvožemio organinės medžiagos kokybės ir sudėties pokyčių indikatoriai, vykstantys dėl dirvožemio naudojimo pokyčių (Landgraf et al, 2006;Šlepetiene et al, 2010).…”

Infrared spectroscopy estimation methods for water-dissolved carbon and amino sugars in diverse Canadian agricultural soils

“…The hot-water-dissolved C (HWDC) consists of more stable components that function as a reserve of nutrients and energy for plants and microorganisms (Bu et al 2011). Compared with the CWDC, the HWDC pool is bigger (5-to 10-fold) and represents a more heterogeneous C pool (Hamkalo and Bedernichek 2014). This is because hot (≥70°C) water kills vegetative cells of microorganisms and extracts many components from microbial biomass, as well as many nonmicrobial soil organic substances (Landgraf et al 2006).…”