Soils have an intrinsic ability to adapt to environmental perturbations compounded by global warming and soil pollution to continuously deliver soil functions, but little is known about how a severely degraded soil regains its functional stability after restoration of vegetation. Surface soils were sampled along slopes in a long-term trial where mono Pinus massoniana was transplanted since 1987 on an eroded bare land and pine litter was either protected or removed on the slopes. We hypothesized that litter quantity would drive changes in soil properties rather than soil microbial communities, which would be main factors in controlling soil functional stability. The specific objectives of this study were: 1) to evaluate the effects of litter management on soil properties, soil microbial community structure and functional stability and 2) to explore the relative role of soil properties and microbial community structure in controlling soil functional stability. The functional stability (resistance and resilience) was determined by measuring how the short-term decomposition of added barley (Hordeum vulgare) powder changed over 28-days following copper addition and heating. Community-level physiological profiles (CLPP) and phospholipid fatty acid (PLFA) profiles were measured to characterize soil microbial community structure. Litter quantity was significantly (P < 0.05) and positively correlated with soil organic carbon (SOC) and microbial biomass carbon (SMB-C) concentration, soil structural properties (porosity and aggregate stability) and the resilience to both perturbations. Soil microbial community structure was significantly separated in two different ways. One was associated with the quantity of litter, SOC concentration and its mediated soil properties (SMB and non-capillary porosity). Another was associated with SOC quality and its mediated soil properties (aggregate stability). These biophysical soil properties (SMB, SOC and capillary porosity) were significantly correlated with the resilience to heating and the resistance and resilience to copper addition. The separations of soil microbial community structure driven by litter quality were significantly correlated with the resistance to heating and the resilience to copper addition. This result suggests that the degraded soil could regain its functional stability after re-vegetation due to the concordant development of soil biophysical habitat and soil microbial community structure through continuous organic inputs. Maintaining litter on floor against anthropogenic collection has an important ecological value.
This study was carried out on a restored site at the Ecological Experimental Station of Red Soil, Chinese Academy of Sciences, Yingtan, Jiangxi Province, China (116 550 3000E, 28 150 2000N). In the experimental site, the topsoil (A and B horizons) had been totally eroded after the clear-cut of native forests in 1950s, forming gully landform (Zhang et al., 2004). P. massoniana trees were planted in 1987 by 3 3 m without changing the landform. Since 1987, part of the restored area was fenced to exclude litter collection and part was accessible to local farmers who used the litter as kindling. They performed a little management experiment on the soil from restored pine forest stands to determine resilience to stress (to mimic anthropogenic stress, including heating) to study the potential for re-vegetation and littler management as a strategic measure for climate change adaptation. See text for experimental manipulation of the soil.
|Climate change impacts||Effect of Nbs on CCI||Effect measures|
|Reduced soil quality||Positive||Functional stability (resilience and resistance) – changes in short term decomposition of barley powder Soil microbial community structure - Community level soil bacterial diversity/phospholipid fatty acid profiles Soil organic carbon, microbial biomass carbon Soil structural stability|
Ecological Experimental Station of Red Soil, Chinese Academy of Sciences, Yingtan, Jiangxi Province, China