The role of environmental, root, and microbial biomass characteristics in soil respiration in temperate secondary forests of Northeast China

Abstract

For secondary forests, the major forest resources in China (accounting for more than 50% of the national total), soil respiration (R S ) and the relationship between R S and various biotic/abiotic factors are poorly understood. The objectives of the present study were to examine seasonal variations in soil respiration during the growing season, and to explore the factors affecting the variation in soil respiration rates for three forest types (Mongolian oak, Manchurian walnut and mixed forests) of temperate secondary forest in Northeast China. The results showed that (1) the maximum total R S rate occurred in July, following a bell-shaped curve with season, (2) for all forest types, the total R S was significantly influenced by soil temperature (P \ 0.01), and did not significantly correlate with soil moisture, (3) compared with fine root biomass, coarse root biomass was more closely related with the root respiration in mixed forest (R 2 = 0.711, P = 0.017) and in Manchurian walnut forest (R 2 = 0.768, P = 0.010), and (4) microbial biomass carbon (MBC) and nitrogen were significantly correlated with heterotrophic R S in Mongolian oak forest (R 2 = 0.664, P = 0.026; R 2 = 0.784, P = 0.008, respectively) and in mixed forest (R 2 = 0.918, P = 0.001; R 2 = 0.967, P = 0.001, respectively). We can conclude that in temperate secondary forests: (1) the R S rate and the relationships between R S and abiotic/biotic factors change greatly with forest types, and (2) R S is strongly influenced by soil temperature, MBC, microbial biomass nitrogen and coarse root biomass in temperate secondary forests.

Responses of soil respiration and its temperature sensitivity to thinning in a pine plantation

“…Additionally, the amount of rainfall that actually reached the soil was lower in control plots due to the higher forest crown interception during light rainfall events (Bao et al, 2004); for example, over 60% of the annual rainfall was intercepted by the pine canopy (Bao et al, 2004). Our observation of lower soil moisture and lower R s in the control stands than in the thinned stands during the growing season of 2009 has also been reported in other studies, especially in dry regions (Defreitas and Enright, 1995;Dore et al, 2010;Grady and Hart, 2006;Zhu et al, 2009). It is clear that in regions with dry seasons, the primary control on R s rate could be soil moisture.…”

Different responses of soil respiration and its components to nitrogen addition among biomes: a meta‐analysis

“…Therefore, root/fine root biomass is often closely correlated with Ra (Fig. f, Lee & Jose, ; Zhu et al ., ), while soil microbial biomass, SOC, and litter mass are widely demonstrated to tightly relate with Rh (Fig. e, Yoshitake et al ., ; Iqbal et al ., ), inducing their significant correlations with Rs (Fig.…”

Nitrogen Addition Affects Soil Respiration Primarily through Changes in Microbial Community Structure and Biomass in a Subtropical Natural Forest

“…This pattern of Rs under N addition is different in N limited ecosystems, which have often been reported to increase Rs via root products and biomass [74]. Importantly, heterotrophic respiration dominates Rs (almost 72%) [75], and the positive relationships were observed between root/fine root biomass and autotrophic respiration [15,76] and microbial biomass and heterotrophic respiration [77]. Additionally, N addition significantly increased root biomass ( Figure S1) and decreased microbial biomass, which collectively suggested that heterotrophic respiration may have decreased even further under N addition.…”