Shifts in soil nutrient concentrations and C:N:P stoichiometry during long-term natural vegetation restoration

PeerJ

article

Rentian Ma¹  Feinan Hu¹  Jingfang Liu¹  Chunli Wang¹  Zilong Wang¹  Gang Liu¹  Shiwei Zhao¹ 

[1] State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Natural Resources and Environment, Northwest A&F University;Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources

关键词: Vegetation restoration;    Soil organic carbon;    Nitrogen;    Phosphorus;    Secondary forest;   

DOI  :  10.7717/peerj.8382

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundEcological stoichiometry (C:N:P ratios) in soil is an important indicator of the elemental balance in ecological interactions and processes. Long-term natural vegetation plays an important role in the accumulation and distribution of soil stoichiometry. However, information about the effects of long-term secondary forest succession on soil stoichiometry along a deep soil profile is still limited.MethodsWe selected Ziwuling secondary succession forest developed from farmland as the study area, investigated the concentrations and stoichiometry of soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) at a depth of 0–100 cm along a 90-year succession chronosequence, including farmland (control), grassland, shrub, early forest, and climax forest.ResultsSOC and TN concentrations significantly increased with increasing restoration age, whereas soil P concentration remained relatively stable across various successional stages. SOC and TN concentrations decreased with an increase in soil depth, exhibiting distinct soil nutrient “surface-aggregation” (high nutrients concentration in the top soil layer). The soil C:P and N:P ratios increased with an increase in restoration age, whereas the variation of the C:N ratio was small and relatively stable across vegetation succession. The nutrient limitation changed along with vegetation succession, transitioning from limited N in the earlier successional stages to limited P in the later successional stages.ConclusionOur results suggest that more nitrogen input should be applied to earlier succession stages, and more phosphorus input should be utilized in later succession stages in order to address limited availability of these elements. In general, natural vegetation restoration was an ecologically beneficial practice for the recovery of degraded soils in this area. The findings of this study strengthen our understanding of the changes of soil nutrient concentration and nutrient limitation after vegetation restoration, and provide a simple guideline for future vegetation restoration and reconstruction efforts on the Loess Plateau.

【 授权许可】

CC BY