Soil Respiration in Stands of Different Tree Species

Puslapiai nurodyti pagal pataisytą leidinįForest ecosystems of different tree species participate actively in climatic and biotic processes, such as photosynthesis, plant and soil respiration so knowledge especially on soil respiration such as CO2 emissions to the atmosphere is of great importance. The aim of the study was to determine soil respiration rate of stands of deciduous (Betula pubescens Ehrh., Quercus robur L.) and coniferous (Larix eurolepis Henry, Thuja occidentalis L.) tree speciesas well as impact of abiotic (soil temperature, humidity, electrical conductivity and pH) and biotic (abundance of undergrowth, shrub, herbs ) factors .Measurements of CO2 emissions, temperature, moisture and electrical conductivuty were performed in-situ in the stands of different tree species with portable ADC BioScientific LCpro+ system and digital electrochemical device “Wet” (Delta-T). Soil samples were collected for the physicochemical analysis simultaneously. Chemical analysis of soil samples were done at the lab of the Environmental Research of the Aleksandras Stulginskis University by standard methods.Soil respiration was highest in the stand of Thuja occidentalis and lowest in the stand of Betula pubescens . According soil respiration intensity in the ascending direction the stands as follow: Thuja˂ Quercus˂ Larix˂ Betula. In the coniferous tree stands, the soil respiration was lower on average 27% comparing to deciduous tree stands. Soil respiration rate from biotic factors was most influenced by abundance of herbaceous vegetation (r = 0.86): as the herbaceous vegetation cover increased, the soil respiration rate also increased. The soil respiration was the most influenced by the abiotic factor – the soil temperature (r = 0.86). The soil respiration rate increased with increasing soil temperature. Sixty year after planting, four stands of different tree species formed specific conditions which influenced soil respiration rateVytauto Didžiojo universitetasŽemės ūkio akademij