Effect of the storage conditions of soil samples on carbon and nitrogen extractability

• Published in: Eurasian soil science Vol. 50; no. 5; pp. 549 - 558
• Main Authors: Makarov, M. I., Kuznetsova, E. Yu, Malysheva, T. I., Maslov, M. N., Menyailo, O. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.05.2017; Springer; Springer Nature B.V
• Subjects: Analysis; Carbon; Carbon content; Drying; Earth and Environmental Science; Earth Sciences; Ecosystems; Extraction processes; Feature extraction; Freezing; Geotechnical Engineering & Applied Earth Sciences; Incubation period; Moisture content; Nitrogen; Organic matter; Organic soils; Soil; Soil Chemistry; Soil conditions; Soil organic matter; Soil water storage; Soils; Storage conditions; Water content; freezing; drying; extraction; carbon; nitrogen; incubation
• ISSN: 1064-2293; 1556-195X
• DOI: 10.1134/S1064229317030085

Concentrations of carbon and nitrogen extractable by 0.05 M K 2 SO 4 (C ext and N ext , respectively) in 14 soils of different ecosystems vary from 16 to 205 and from 4 to 53 mg/kg, respectively. The portion of C ext in soil organic matter is 0.06 to 0.38% of total carbon, and the portion of N ext is 0.12–1.05% of total nitrogen. The storage of samples and their preparation to analysis differently affect the extractability of elements. The concentration of C ext is less variable than the concentration of N ext . An increase in C extractability (by 1.4–6.7 times) is a common feature of all soils under drying; at the following incubation of dried soils, the extractability of C decreases by 28–56%. The extractability of N increases not only under drying (by 1.5–7.1 times) and the following incubation of samples (by 25–60% to 2–3 times), but also under freezing of most soils and at the incubation of fresh and defrozen samples. A close direct correlation is observed between the initial water content of soil and the relative increase in C extractability under drying and N extractability under freezing and drying.