Soil Carbon and Nutrient Dynamics Following Cessation of Anthropogenic Disturbances in Degraded Subtropical Forests

Abstract

Soil carbon (C) and nutrient availability is fundamental to terrestrial biodiversity and functionality. In recent decades, the restoration of degraded forests has become a major concern worldwide, and recent studies have demonstrated that soil C and nitrogen (N) increase over time following restoration. However, our understanding of the responses of soil phosphorus (P), calcium (Ca), potassium (K) and magnesium (Mg) and elemental stoichiometric ratios to restoration remains elusive. We employed a chronosequence to examine the responses of C and macronutrients in three soil layers (0–10 cm, 10–20 cm and 20–30 cm) to the time (0 to 31 years) since the cessation of anthropogenic disturbances in the degraded subtropical forests of Eastern China. We found that stand basal area, soil water content, organic matter content and C concentration and stock increased, while soil pH and bulk density decreased over time, with the most pronounced effects within the 0–10 cm layer. Total and available N and K as well as available P and total Mg increased, while total P in the 20–30 cm layer and Ca in all soil layers decreased over time. The mass concentration ratios of soil C to total N and available N, P and K decreased, whereas those for C to total P and Ca as well as total N to total P and available N to available P increased over time. Our results suggest that soil C accumulation and biologically driven nutrients increase, while nutrients that are driven primarily through geochemical mechanisms decrease with live biomass accumulation following restoration. Copyright © 2017 John Wiley & Sons, Ltd.

Rapid increases in fine root biomass and production following cessation of anthropogenic disturbances in degraded forests

“…Our results indicate that cessation of anthropogenic disturbances in the highly degraded forests, despite that they were also dominated by trees prior to restoration, could double FR biomass and production within 6 years after closure. Given the strong contributions of roots and root‐associated microorganisms to soil carbon (Clemmensen et al, ; Jackson et al, ; McCormack et al, ; Yuan et al, ), our finding indicates a profound contribution of China's large‐scale closure (Feng et al, ; Ouyang et al, ) to the carbon sequestration and nutrient cycling of China's forests and their global contributions. Our results offer a new and important understanding of the importance of ecological restoration to ecosystem function.…”

“…Compared with tree plantation establishment, closure is more cost‐effective for restoring degraded forests (Ma, Lv, & Li, ; Xu et al, ). Previous studies have shown that tree canopy cover and stand basal area increase quickly (Xu et al, ), canopy dominance shifts from early‐ to late‐successional tree species (Hou, R‐d, B‐w, & Wang, ), and soil carbon concentration and pool size increase (Feng, Ma, Fu, & Chen, ) over time following closure. Although restoring ecosystem productivity is regarded as an important criterion for success (Ruiz‐Jaen & Aide, ), the effect of mountain closure on ecosystem productivity has rarely been examined.…”

“…Compared with tree plantation establishment, closure is more cost-effective for restoring degraded forests (Ma, Lv, & Li, 2013;Xu et al, 2015). Previous studies have shown that tree canopy cover and stand basal area increase quickly (Xu et al, 2015), canopy dominance shifts from early-to late-successional tree species (Hou, R-d, B-w, & Wang, 2004), and soil carbon concentration and pool size increase (Feng, Ma, Fu, & Chen, 2017) over time following closure.…”

Effect of multipurpose trees and shrubs on degraded mined‐out soil in a semi‐deciduous forest zone of West Africa

“…According to Luna et al (), application of organic amendment enhanced soil structure and infiltration and reduced soil losses by erosion. The development of rooting systems, addition of biomass, and slight anthropogenic perturbation after reclamation improved soil structure, increased porosity, and decreased soil bulk density (Akala & Lal, ; Feng, Ma, Fu, & Chen, ; Luna et al, ). In their study, Luna et al () made similar observation of increasing soil moisture along the chronosequence.…”

Assessment of potential land degradation and recommendations for management in the south subtropical region, Southwest China

“…In mountainous forest regions, the vegetation and soil parameters were investigated to evaluate forest degradation at the field level. Forest degradation caused reduced vegetation and increased soil disturbances, such as damaged biodiversity and a reduction in soil carbon and nutrients (Cao, ; Feng, Ma, Fu, & Chen, ). Combined with the study area's local situation, we considered commonly accepted indicators related to degradation, such as canopy density, the diversity index (Shannon's diversity index), soil physical properties (soil moisture and soil bulk density), soil organic matter, and soil total nitrogen (Cowie et al, ; Kairis et al, ).…”