Impact of nitrogen fertilization and cropping systems on aggregate-bound soil organic carbon fractions in Southern India

verfasst von
Usha Kumari, A. Sathish, Dev Raj, Pooja Rani, Seema Sheoran, Kavita Tanwar, Sarita Rani, Nidhi Kamboj, Ritambhara Jakhar, Rajbir Garg, Stephan Peth
Abstract

Understanding soil organic carbon fractions in southern India is crucial for enhancing soil health, crop productivity, and sustainable land management. It is majorly affected by cropping systems, nitrogen levels, irrigation management, etc. Therefore, the present study aimed to investigate the effects of varying nitrogen doses [N1: No nitrogen, N2:100% of recommended dose of N (RDN), and N3: 200% RDN] and different cropping systems (fieldbean, finger millet, and maize) on aggregate-associated soil organic carbon and its fractions, as well as their impact on aggregate stability under rainfed and irrigated conditions. Aggregates were separated into different classes and analyzed for organic carbon and its fractions (dissolved organic carbon, microbial biomass carbon, potassium permanganate oxidizable carbon, and non-labile organic carbon). Applying 200% RDN enhanced total organic carbon (TOC) and its fractions. Conversely, aggregate stability was not influenced by N levels as determined by mean weight diameter and tensile strength. Macroaggregates (> 250 μm) had higher total organic carbon and their fractions than microaggregates (< 250 μm). The effect of the cropping systems was significant and the maize cropping system had the highest content of TOC and other fractions, followed by fieldbean and finger millet cropping systems. Mean weight diameter (MWD) was significantly higher in finger millet-grown soils. The impact of nitrogen fertilizer and cropping systems on aggregate-associated organic carbon was more pronounced in irrigated than rainfed conditions, indicating the potential for carbon sequestration under irrigated conditions. Thus, the optimum level of nitrogen and the type of cropping system adopted influence the distribution pattern of aggregate-associated organic carbon, along with its fractions that play a pivotal role in carbon accumulation and stabilization.

Organisationseinheit(en)
Institut für Erdsystemwissenschaften
Externe Organisation(en)
CCS Haryana Agricultural University
University of Agricultural Sciences, Bangalore
Krishi Vigyan Kendra
Typ
Artikel
Journal
Scientific reports
Band
15
ISSN
2045-2322
Publikationsdatum
30.09.2025
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Allgemein
Ziele für nachhaltige Entwicklung
SDG 2 – Kein Hunger, SDG 15 – Lebensraum Land
Elektronische Version(en)
https://doi.org/10.1038/s41598-025-09036-5 (Zugang: Offen)