13C abundance, water-soluble and microbial biomass carbon as potential indicators of soil organic carbon dynamics in subtropical forests at different successional stages and subject to different nitrogen loads

• Published in: Plant and soil Vol. 320; no. 1-2; pp. 243 - 254
• Main Authors: Fang, Hua-Jun, Yu, Gui-Rui, Cheng, Shu-Lan, Mo, Jiang-Ming, Yan, Jun-Hua, Li, Shenggong
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.07.2009; Springer; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Biochemistry and biology; Biological and medical sciences; Biomass; Biomedical and Life Sciences; Carbon; Chemical, physicochemical, biochemical and biological properties; Ecology; Ecosystems; Forest ecosystems; Forest soils; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Life Sciences; Microbiology; Nitrogen; Organic carbon; Organic matter; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Plant Physiology; Plant Sciences; Plant species; Rainforests; Regular Article; Soil dynamics; Soil science; Soil Science & Conservation; Soil surfaces; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Water consumption; SOC turnover; Successional stages; N deposition; C natural abundance; Labile C fractions; Subtropical China; Organic carbon; Organic matter; Forests; Carbon Isotopes; Potential; Water solubility; Chemical properties; Non metal; Subtropical zone; Load; Dynamic characteristic; Solubility; Nitrogen; Microbial biomass; Indicator; Group VA element; Soils; C-13; Soil plant relation
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-009-9890-7

Chronic atmospheric nitrogen deposition affects the cycling of carbon (C) and nitrogen (N) in forest ecosystems, and thereby alters the stable C isotopic abundance of plant and soil. Three successional stages, disturbed, rehabilitated and mature forests were studied for their responses to different nitrogen input levels. N-addition manipulative experiments were conducted at low, medium and high N levels. To study the responses of C cycling to N addition, the C concentration and 13 C natural abundances for leaf, litter and soil were measured. Labile organic carbon fractions in mineral soils were measured to quantify the dynamics of soil organic C (SOC). Results showed that three-year continuous N addition did not significantly increase foliar C and N concentration, but decreased C/N ratio and enriched 13 C in N-rich forests. In addition, N addition significantly decreased microbial biomass C, and increased water soluble organic C in surface soils of N-rich forests. This study suggests that N addition enhances the water consumption per unit C assimilation of dominant plant species, restricts SOC turnover in N-poor forests at early and medium successional stages (thus favored SOC sequestration), and vice versa for N-rich mature forests.