Nitrogen effects on the carbon cycle in forest ecosystems: A review
Journal
Russian Journal of Forest Science
Journal Volume
2018
Journal Issue
2
Pages
143-159
Date Issued
2018
Author(s)
Abstract
We reviewed the recent publications on the nitrogen cycle and application of nitrogen fertilizers in forest ecosystems. The level of nitrogen precipitation in Russia is much less than in Europe or USA. Nitrogen fixation intensity contributes only 1–2% of the stands’ total demand in nitrogen. The main source of nitrogen for trees is mineralization and migration of nitrogen from soil organic matter. We show that intensification of forestry and sustainable forest management, when cut storages is less than annual yield, are impossible without nitrogen fertilization in Russia. However, application of nitrogen fertilizers can lead both to losses and accumulation of soil carbon comparable to the accumulation of carbon in plant biomass due to the fertilization. Losses of carbon in soils after input of nitrogen are obviously due to the rise in availability of nitrogen for heterotrophic microorganisms decomposing organic matter. Accumulation of organic matter is linked to inhibition of heterotrophic activity with nitrogen. There are two mechanisms of the inhibiting published, as follows: 1) suppression of ligninolytic fungi, 2) polymerization of heavily humified organic matter. Overall the fate of soil carbon controls the effect from nitrogen mineral fertilizers in forest ecosystems. © 2018, Izdatel’stvo Nauka. All rights reserved.
Subjects
Carbon cycle; Forest ecosystems; Nitrogen fertilizers; Soil microorganisms
Type
journal article