Aerobic and Anaerobic Respiration in Profiles of Polesie Lubelskie Peatlands

Abstract

A b s t r a c t. Soil respiration is a very important factor influencing carbon deposition in peat and reflecting the intensity of soil organic matter decomposition, root respiration, and the ease of transporting gases to the surface. Carbon dioxide release from three different peat soil profiles (0-80 cm) of the Polesie Lubelskie Region (Eastern Poland) was analyzed under laboratory conditions. Peat samples were incubated at 5, 10, and 20°C in aerobic and anaerobic environments, and their CO 2 -evolution was analyzed up to 14 days. The respiration activity was found to be in the range of 0.013-0.497 g CO 2 kg -1 DW d -1 . The respiratory quotient was estimated to be in the range of 0.51-1.51, and the difference in respiration rates over 10°C ranged between 4.15 and 8.72 in aerobic and from 1.15 to 6.53 in anaerobic conditions. A strong influence of temperature, depth, the degree of peat decomposition, pH, and nitrate content on respiration activity was found. Lack of oxygen at low temperature caused higher respiration activity than under aerobic conditions. These results should be taken into account when the management of Polish peatlands is considered in the context of climate and carbon storage, and physicochemical properties of soil in relation to soil respiration activity are considered.K e y w o r d s: peat ecosystem, aerobic and anaerobic respiration, carbon dioxide

Responses of peat carbon at different depths to simulated warming and oxidizing

“…During incubation the jars were completely sealed, permitting only 5-10 minutes of gas exchange time. Therefore, the short incubation period (35 days) did not cause much moisture loss, similar to other short incubation experiments Szafranek-Nakonieczna and Stêpniewska, 2014).…”

“…At the same time, the difference of Q 10 values under AE and AN conditions also demonstrated that soil carbon became more liable to microbes under O 2 abundant environment (Lee et al, 2012;Wang et al, 2013). Though the effect of temperature and O 2 on Rs had been well studied in other peatlands (Knoblauch et al, 2013;Moore and Dalva, 1997;Szafranek-Nakonieczna and Stêpniewska, 2014;Treat et al, 2014;Wang et al, 2013), our results from an area of midlatitude and high altitude were different from others. Rs increase with oxidizing or 10°C warming was much lower in our study than in other incubation studies (85.8-226.1% and 128.9-200%) (Table S1), indicating the lower sensitivity of peat in this area to warming and oxidizing, which can be explained by the different climate (temperature and precipitation) and vegetation in our study area from those of the others (Table S1).…”

Calibrating the sqHIMMELI v1.0 wetland methane emission model with hierarchical modeling and adaptive MCMC

“…The model calibration consists of several steps but can be summarized as first estimating the posterior with MCMC and then based on those results, recalibrating the objective func- -) and ζexu (-)) priors were relaxed by a factor of 3 to allow for a more data-constrained resampling and to accommodate the low values of Q 10 reported by Szafranek-Nakonieczna and Stepniewska (2014). Note that the values of the prior for these two parameters were sampled at each iteration with Gibbs sampling.…”

Irrigation and Greenhouse Gas Emissions: A Review of Field-Based Studies

“…Changes in soil moisture greatly affect soil redox conditions, increase in soil moisture decreases soil redox potential, which in turn alters the likelihood and rate of GHGs emissions; some studies have shown that the change in redox potential is closely related to N 2 O emission [44]. Studies have demonstrated that anoxic conditions will suppress CO 2 production due to a shift from aerobic to anaerobic microbial respiration, which occurs at a slower rate [50][51][52]. Effects of individual irrigation strategies on GHG emissions have been studied extensively; however, most studies compared a single irrigation treatment to the effects of dryland/rainfed (i.e., non-irrigated) treatment [53][54][55].…”