Effect of temperature and moisture on the mineralization and humification of leaf litter in a model incubation experiment

Eurasian Soil Science - Tập 50 - Trang 422-431 - 2017
A. A. Larionova1, A. N. Maltseva1, V. O. Lopes de Gerenyu1, A. K. Kvitkina1, S. S. Bykhovets1, B. N. Zolotareva1, V. N. Kudeyarov1
1Institute of Physicochemical and Biological Problems of Soil Science, Russian Academy of Sciences, Pushchino, Russia

Tóm tắt

The mineralization and humification of leaf litter collected in a mixed forest of the Prioksko-Terrasny Reserve depending on temperature (2, 12, and 22°C) and moisture (15, 30, 70, 100, and 150% of water holding capacity ( WHC)) has been studied in long-term incubation experiments. Mineralization is the most sensitive to temperature changes at the early stage of decomposition; the Q 10 value at the beginning of the experiment (1.5–2.7) is higher than at the later decomposition stages (0.3–1.3). Carbon losses usually exceed nitrogen losses during decomposition. Intensive nitrogen losses are observed only at the high temperature and moisture of litter (22°C and 100% WHC). Humification determined from the accumulation of humic substances in the end of incubation decreases from 34 to 9% with increasing moisture and temperature. The degree of humification CHA/CFA is maximum (1.14) at 12°C and 15% WHC; therefore, these temperature and moisture conditions are considered optimal for humification. Humification calculated from the limit value of litter mineralization is almost independent of temperature, but it significantly decreases from 70 to 3% with increasing moisture. A possible reason for the difference between the humification values measured by two methods is the conservation of a significant part of hemicelluloses, cellulose, and lignin during the transformation of litter and the formation of a complex of humic substances with plant residues, where HSs fulfill a protectoral role and decrease the decomposition rate of plant biopolymers.

Tài liệu tham khảo

L. N. Aleksandrova, Soil Organic Matter and the Processes of Its Transformation (Nauka, Leningrad, 1980) [in Russian].

K. S. Bobkova, A. V. Mashika, and A. V. Smagin, Dynamics of the Content of Organic Carbon in Automorphic Soils of Middle-Taiga Spruce Forests (Nauka, St. Petersburg, 2014) [in Russian].

M. M. Kononova, Problem of Soil Humus and Modern Challenges of Its Study (Academy of Sciences of the Soviet Union, Moscow, 1951) [in Russian].

E. Yu. Milanovskii, Soil Humus Substances as the Natural Hydrophobic-Hydrophilic Compounds (GEOS, Moscow, 2009) [in Russian].

M. A. Nadporozhskaya, L. B. L’vova, N. V. Kovsh, E. I. Fedoros, and O. G. Chertov, “Influence of lithogenic factor on the transformation of nitrogen compounds in forest soils,” Proceedings of the V All-Russian Conf. with International Participation on Forest Soil Science “Diversity of Forest Soils and Biological Diversity of Forests (Pushchino, 2013), pp. 84–86

D. S. Orlov, O. N. Biryukova, and N. I. Sukhanova, Organic Matter in the Soils Russia (Nauka, Moscow, 1996) [in Russian].

V. K. Pestryakov, N. V. Kovsh, A. I. Popov, and S. N. Chukov, “Modeling of the organic matter transformation under laboratory conditions,” Pochvovedenie, No. 3, 30–41 (1990).

A. V. Smagin, Gas Phase of Soils (Moscow State Univ., Moscow, 1999) [in Russian].

L. S. Travnikova, Organomineral Interactions: Role in Soil Formation, Fertility, and Tolerance Toward Degradation (Dokuchaev Soil Science Inst., Moscow, 2001) [in Russian].

S. Ya. Trofimov, P. Bottner, and M. M. Coateaux, “Decomposition of organic matter in organic horizons of forest soils in laboratory conditions,” Eurasian Soil Sci. 31, 1349–1357 (1998).

O. G. Chertov and M. A. Nadporozhskaya, “The effect of intensive nitrogen release during decomposition of the plant remains in laboratory conditions,” Izv. S.-Peterb. Lesotekh. Akad., No. 197, 272–283 (2011).

O. G. Chertov, S. N. Chukov, M. A. Nadporozhskaya, A. I. Popov, N. V. Kovsh, A. V. Belenets, I. N. Lapshina, V. D. Talashkina, and V. D. Davydov, “Analysis of the functional-dynamic characteristics of transformation of soil organic matter,” Vestn. S.-Peterb. Gos. Univ., Ser. 3: Biol., No. 3, 106–110 (1994).

N. Fierer, J. M. Craine, K. McLauchlan, and J. P. Schimel, “Litter quality and the temperature sensitivity of decomposition,” Ecology 86, 320–326 (2005).

C. M. Preston, J. R. Nault, J. A. Trofymov, and C. Smyth, “Chemical changes during 6 years decomposition of 11 litters in some Canadian forest sites,” Ecosystems 12, 1053–1077 (2009).