Leaf litter C and N cycling from a deciduous permanent crop

• Published in: Soil science and plant nutrition (Tokyo) 2016-05, Vol.62 (3), p.271-276
• Main Authors: Khalsa, Sat Darshan S., Almanza, Carolina A., Brown, Patrick H., Smart, David R.
• Format: Article
• Language: English
• Subjects: Abundance; Ammonium; Biomass; Carbon; Crops; Cycles; Decomposition; Enrichment; Immobilization; Leaf litter; Leaves; Litter; Microorganisms; Mineralization; Nitrates; Nitrogen; Organic carbon; Organic nitrogen; Pools; Prunus dulcis; Respiration; soil respiration; Soil testing; Soils; Total organic carbon
• ISSN: 0038-0768; 1747-0765
• DOI: 10.1080/00380768.2016.1188413

Our understanding of leaf litter carbon (C) and nitrogen (N) cycling and its effects on N management of deciduous permanent crops is limited. In a 30-day laboratory incubation, we compared soil respiration and changes in mineral N [ammonium (NH 4 + -N) + nitrate (NO 3 - -N)], microbial biomass nitrogen (MBN), total organic carbon (TOC) and total non-extractable organic nitrogen (TON) between a control soil at 15 N natural abundance (δ 15 N = 1.08‰) without leaf litter and a treatment with the same soil, but with almond (Prunus dulcis (Mill.) D.A. Webb) leaf litter that was also enriched in 15 N (δ 15 N = 213‰). Furthermore, a two-end member isotope mixing model was used to identify the source of N in mineral N, MBN and TON pools as either soil or leaf litter. Over 30 d, control and treatment TOC pools decreased while the TON pool increased for the treatment and decreased for the control. Greater soil respiration and significantly lower (p