Litterfall and nutrients return to soil in pure and mixed stands of oak and beech

Abstract

Litterfall is a significant pathway for the return of nutrients and carbon (C) to the soil in forest ecosystems. It provides long-term maintenance of nutrients in the forest ecosystem. For maintaining healthy forest ecosystems, knowledge about litterfall, energy, and nutrient inputs to the soil biota is important. This study was aimed to determine litterfall and nutrient return to soil in pure and mixed stands of oak (Quercus petraea (Mattuschka) Liebl.) and beech (Fagus orientalis Lipsky) in Ataturk Arboretum, Turkey. Litterfall has been collected over 3 years from 2009 to 2011 at all three sites. Litter traps were used for this purpose, and the trapped samples were sorted into fractions, which included leaves (foliar), branches/twigs, and others (e.g., acorn, flowers, bark, etc.). The concentrations of 14 elements (C, N, P, K, Ca, Na, Mg, Mn, Fe, Al, Zn, Pb, Ni, and Cu) were analyzed. The highest amount of litterfall in the three areas was measured in 2010. The average total litterfall ranged from 3947 to 4578 kg/ha. The average amounts of leaflitter in oak, beech, and oak-beech sites were 86%, 62%, and 75%, respectively. Nutrient concentrations were higher in leaves and the least in branches and twigs. Element concentrations generally showed a descending order as C>Ca>N>Mg>K>Mn>P>Al>Fe>Na>Zn>Cu>Ni> in all the sites. The pure and mixed sites were not significantly different by years, but there was a significant difference in the nutrient concentrations of litterfall fractions between the two sites.