Soil organic matter gain by reduced tillage intensity: Storage, pools, and chemical composition

• DOI: 10.1016/j.still.2022.105584
• Publication Date: 2022-11-25T01:20:57Z
• Authors: Gergely Jakab; Balázs Madarász; Malihe Masoudi; Máté Karlik; Csilla Király; Dóra Zacháry; Tibor Filep; Igor Dekemati; Csaba Centeri; Thulfiqar Al-Graiti; Zoltán Szalai
• Keywords: Chernozem; Topsoil; Soil carbon; Conventional tillage; Soil structure

Soil organic matter (SOM) loss due to intensive cultivation is the focus of studies on climate change and food security. Dropping tillage intensity has been widely reported as a potential tool for SOM increase; however, chemical composition, storage mechanisms, vertical distribution gain are not fully understood, especially in calcareous soils. This study aimed analyze increased conditions among pools depths an eighteen-year-long field experiment comparing under conventional moldboard plowing (PT), deep (DC), no (NT) systems base-saturated Endocalcic Chernozem (Loamic). samples were collected from 0–10 cm 30–40 soil layers divided into mineral phase-associated (<63 µm, stable pool; MPAOM) aggregate related (>63 labile pool). The was further particulate (POM, <1.0 g cm-3) aggregates-associated (AAOM, >1.0 cm-3). Results indicated overall increase carbon (SOC) concentration topsoil order PT<DC<NT. surplus did manifest POM but either MPAOM or AAOM fractions. likely resulted above-ground plant residue input, SOC content layer change. additional SOM, stabilized soil, affect composition between fractions, suggesting preferential binding by fine fraction aggregates. suggests more aromatic less complex fraction, even recent years. fractionation maintains increases difference (soil fractions) terms composition. In addition, differentiation result mitigation established stratification aromaticity. These results suggest key role dissolved movement profile driving force aromaticity with depth. also emphasize local OM changes, establishing complexity process difficulties holistic model construction.