Different soil respiration responses to litter manipulation in three subtropical successional forests

Abstract

Aboveground litter inputs have been greatly altered by human disturbances and climate change, which have important effects on soil respiration. However, the knowledge of how soil respiration responds to altered litter inputs is limited in tropical and subtropical forests. We conducted an aboveground litterfall manipulation experiment in three successional forests in the subtropics to examine the soil respiration responses to different litter inputs from January 2010 to July 2012. The soil respiration decreased by 35% in the litter exclusion treatments and increased by 77% in the doubled litter additions across all three forests. The reduction in soil respiration induced by the litter exclusion was greatest in the early successional forest, which may be related to a decrease in the soil moisture and shifts in the microbial community. The increase in soil respiration produced by the doubled litter addition was largest in the mature forest, which was most probably due to its relatively high quantity and quality of litterfall. Our results suggest that the effect of reduced litter inputs on the soil respiration lessened with forest succession but that the doubled litter inputs resulted in a stronger priming effect in the mature forest than in the other two forests.

Contribution of soil respiration to the global carbon equation

“…At a global scale, annual litter production is highly correlated with SOC and Rs (Raich and Tufekciogul, 2000;Davidson et al, 2002a;Sayer et al, 2007;Han et al, 2015). In addition to litter production, the species composition of vegetation may alter litter quality and thus Rs (Hättenschwiler et al, 2005;Chiang et al, 2014).…”

Global effects of plant litter alterations on soil CO2 to the atmosphere

“…The priming effect could be quantitatively significant and presents a potent challenge to first-order kinetic models of soil C (Fontaine et al, 2007;Heimann & Reichstein, 2008;Sayer et al, 2011). However, perspectives on the priming effect of plant litter on Rs are mixed with some empirical support (Han, Huang, Liu, Zhou, & Xiao, 2015;Sayer, Powers, & Tanner, 2007;Sayer et al, 2011). Others have described priming as short-term and idiosyncratic (Cardinael et al, 2015;Dalenberg & Jager, 1989;Leff et al, 2012;Liu, Lin et al, 2017).…”

Interactions between Vegetation, Hydrology, and Litter Inputs on Decomposition and Soil CO2 Efflux of Tropical Forests in the Brazilian Pantanal

“…The direct effects of litter production on Rsoil described here are consistent with results reported from other ecosystems, indicating that the effect of litter production on ecosystem C emission may be general across diverse forest types. For example, we compiled results from litter manipulation experiments reported in the literature [23,25,[27][28][29][49][50][51][52][53][54] and used linear regression to determine if there were consistent trends in the log response ratio of Rsoil [LN(Rsoil treatment/Rsoil control)] as a function of relative litter pool size ( Figure 6). Litter addition and/or removal resulted in surprisingly similar relative responses in Rsoil in spite of widely varying experimental methods (plot sizes, measurement intervals) and forest types ( Figure 6).…”

“…However, climate change will also alter forest phenology [16], mortality [17], productivity [4,18,19], and species composition [20], which can alter litter decomposition and Rsoil through changes in soil and forest floor C quantity and quality [11,21,22]. Plant litter has been estimated to contribute between 18 and 48% to the total Rsoil in temperate [23][24][25][26], subtropical [27], and tropical forests [28,29]. Some of this contribution is due to the "priming" effect of fresh litter on rates of Rsoil [29]; however, litter pool mass and thickness also feedback on soil moisture and temperature [11,14,15,30].…”