TITLE:
An Influence of Multiple Drying/Rewetting Cycles upon the Respiration of Organic Forest Soil
AUTHORS:
Zofia Fischer
KEYWORDS:
Soil-Water Relationships, Climate Change, Carbon Dioxide Excretion
JOURNAL NAME:
Open Journal of Soil Science,
Vol.9 No.9,
September
24,
2019
ABSTRACT: It is already known that repeating cycles of drying and rewetting decrease the metabolic activity of the soil. The aim of this paper is to explain on the basis of a laboratory experiment how the respiratory processes of organic soil collected from the forest ecosystem typical for a moderate climate are changing during ten consecutive events of watering, and how alters the relationship between changing humidity of the soil and oxygen consumption/carbon dioxide emission. After 10 cycles, the respiration decreases by 2.4 times however amounts of excreted carbon dioxide and consumed oxygen do not differ between cycles 9 and 10. In successive DRW cycles also the relationship between oxygen consumption/carbon dioxide excretion and humidity level changes. This relationship is logarithmic and the analysis of subsequent regressions indicates the direction of those changes. In successive cycles the value of β coefficient (slope) decreases, and both the values of β and coefficient R2 are always higher for oxygen consumption that for carbon dioxide excretion. This indicates that processes involving oxygen consumption are always more sensitive to fluctuations of humidity than processes producing carbon dioxide. The optimum of respiration declines in successive DRW cycles.