Temperature Sensitivity of Soil Respiration to Nitrogen Fertilization: Varying Effects between Growing and Non-Growing Seasons

Abstract

Nitrogen (N) fertilization has a considerable effect on food production and carbon cycling in agro-ecosystems. However, the impacts of N fertilization rates on the temperature sensitivity of soil respiration (Q10) were controversial. Five N rates (N0, N45, N90, N135, and N180) were applied to a continuous winter wheat (Triticum aestivum L.) crop on the semi-arid Loess Plateau, and the in situ soil respiration was monitored during five consecutive years from 2008 to 2013. During the growing season, the mean soil respiration rates increased with increasing N fertilization rates, peaking at 1.53 μmol m−2s−1 in the N135 treatment. A similar dynamic pattern was observed during the non-growing season, yet on average with 7.3% greater soil respiration rates than the growing season. In general for all the N fertilization treatments, the mean Q10 value during the non-growing season was significantly greater than that during the growing season. As N fertilization rates increased, the Q10 values did not change significantly in the growing season but significantly decreased in the non-growing season. Overall, N fertilization markedly influenced soil respirations and Q10 values, in particular posing distinct effects on the Q10 values between the growing and non-growing seasons.

Coupling temperature‐dependent spatial turnover of microbes and plants using the metabolic theory of ecology

“…Our results, together with those of previous studies (Hawkins et al, 2007;Wang et al, 2009;Zhou et al, 2016), showed that the values of E for both the α and β diversities of the most diverse microbes may be lower than the predicted range of 0.60-0.70 eV (Brown et al, 2004;Allen et al, 2005). For reference, the E-values were expressed in terms of Q 10 , which is defined as the rate of change with a 10°C increase in temperature and were calculated according to Liu et al (2016). The E-values for bacteria (0.047 eV) and the functional genes (0.341 eV) are equivalent to Q 10 values of 1.07 and 1.64; therefore, the spatial turnover of the soil microbial community increases c. 1.1-1.6 times for every 10°C increase in mean annual environmental temperature.…”

“…For reference, the E ‐values were expressed in terms of Q 10 , which is defined as the rate of change with a 10°C increase in temperature and were calculated according to Liu et al . (2016). The E ‐values for bacteria (0.047 eV) and the functional genes (0.341 eV) are equivalent to Q 10 values of 1.07 and 1.64; therefore, the spatial turnover of the soil microbial community increases c .…”

Interactions between labile carbon, temperature and land use regulate carbon dioxide and methane production in tropical peat

“…? /NO 2 -/NO 3 -) limitation (Liu et al 2016;Wang et al 2010), although in this study only total peat nitrogen was assessed and this did not differ significantly between peat types. The lack of significant difference in temperature sensitivity of CO 2 and CH 4 production with glucose addition may be because despite an increase in carbon lability, unamended peats still had sufficient available carbon for respiration due to high organic matter content (Dai et al 2017).…”

Soil respiration dynamics in forage-based and cereal-based cropping systems in central Italy

“…Most studies that have investigated soil C dynamics were performed in ecosystems where human disturbance is relatively rare, such as forest ecosystems (Casals R S rates in wheat (Liu et al, 2016). For HW and PW, no R S peaks were detected immediately after application of N fertilizer.…”