Variations in Organic Carbon Content and Dehydrogenases Activity in Post-Agriculture Forest Soils: A Case Study in South-Western Pomerania

Katarzyna Wiatrowska,Jolanta Komisarek,Janusz Olejnik

doi:10.3390/f12040459

Abstract

Temperate forest soils of Europe are regarded as an important sink of carbon and thought to have potential to sequester CO2 from atmosphere. However, there are insufficient data not only on organic carbon (OC) content in forest soils and its temporal changes but also on microbiological activity and especially their relationship to carbon turnover. In this study seven research plots were located on afforested land in the north-western part of Poland in Tuczno Forest District (Western Pomerania) in order to examine seasonal variation in OC content and dehydrogenases activity (DHA) during 2012–2016. Based on the studies conducted, statistically significant seasonal variation of the OC content was observed. Higher amounts of OC in the A horizon were observed during spring and autumn seasons and lower in summer. However, no seasonal variation on OC content was observed in the organic horizon (O horizon). Although DHA is thought to exhibit strong seasonal variability, no seasonal variation on DHA was observed. However, a statistically significant difference was observed among studied years (2012–2016), a sharp drop of DHA was noted from spring 2014. Statistical analyses revealed that OC content in soils was a function of forest stand age and progressing acidification of soil. Moreover, OC content in O horizon was negatively correlated with soil moisture and DHA, suggesting that periods with higher microbial activity lead to lower accumulation of carbon in the O horizon. During 2012–2016 only for the O horizon was an increase in OC content was observed.

Highlights

Forest ecosystems play an important role in the global carbon cycle, accumulating the largest amounts of this element among all terrestrial ecosystems
Soil cover of the studied area was mainly represented by Brunic Eutric Arenosol (Ochric) that developed from fluvio-glacial outwash materials
Research plot 6 was represented by Brunic Eutric Arenosol (Cumullic, Ochric), which was related to the location of this surface in a local depression

Summary

Introduction

Forest ecosystems play an important role in the global carbon cycle, accumulating the largest amounts of this element among all terrestrial ecosystems. It is estimated that 80% of the carbon resources contained in terrestrial ecosystem biomass are associated with forest areas. 70% of the pedosphere’s organic carbon resources are accumulated in forest soils [1]. Any consideration of carbon circulation in forest ecosystems must include soil. The carbon resources accumulated in soil exceed those in the atmosphere by a factor of 3.3 and those in the biomass of the biosphere by 4.5. Higher biomass production and organic carbon accumulation occur in areas with higher amounts of rainfall [5,6]

Objectives

Methods

Results

Discussion

Conclusion