Effects of nitrogen and phosphorus additions on aggregate-associated soil carbon and interactions with phosphorus fractions in evergreen broad-leaved forest

Jiangxi Agricultural University

Clc Number:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
  • |
  • Comments

    In order to explore how phosphorus input regulates the effects of atmospheric nitrogen deposition on soil aggregate organic carbon content and the coupling relationship between carbon and phosphorus, a long-term monitoring test platform for nutrient addition for 6 years (2015-2021) was established in the soil of evergreen broad-leaved forest, including 4 treatments: Control (P0+N0, 0 kg P ha-1 a -1 +0 kg N ha-1 a -1), nitrogen addition (P0+N100, 0 kg P ha-1 a -1 +100 kg N ha-1 a -1), phosphorus input (P50+N0, 50 kg P ha-1 a -1 +0 kg N ha-1 a -1) and nitrogen and phosphorus were simultaneously input (P50+N100, 50 kg P ha-1 a -1 +100 kg N ha-1 a -1), 3 replicates were performed, and a total of 12 plots were obtained. 0-10 cm soil samples were collected from the sample site in August 2021 to determine the basic physical and chemical properties, soil particle size distribution, phosphorus components of soil aggregates of different particle sizes, and organic carbon (SOC) content. The results showed that: (1) Under P0 (0 kg P ha-1 a-1 without P input) treatment, nitrogen addition significantly increased the proportion of large aggregates, reduced the content of clay and powder particles, and increased the SOC content of each aggregate particle size. Nitrogen addition significantly decreased and increased the content of LP and RP components in aggregate clay and powder, respectively. (2) Under P50 (50 kg P ha-1 a-1 with P input) treatment, nitrogen addition significantly increased the mean geometric mass diameter (GMD) of soil aggregates, and increased the proportion of large aggregates while decreased the proportion of small aggregates. Nitrogen addition had no significant effect on the content of phosphorus and SOC in aggregates of different particle sizes. (3) Under P0 treatment, soil aggregate SOC showed a positive correlation with refractory phosphorus. Under P50 treatment, SOC of soil aggregates had no significant correlation with all functional phosphorus components. It is concluded that under P0 treatment, nitrogen addition can increase soil organic carbon retention by increasing the insoluble phosphorus in aggregate viscosity and powder particle size of evergreen broad-leaved forest. Under P50 treatment, the effect of nitrogen addition on organic carbon in each particle size may be regulated by biological factors and has nothing to do with the availability of phosphorus. In conclusion, the effect of nitrogen deposition on the coupling relationship between carbon and phosphorus in soil aggregates in evergreen broad-leaved forests is regulated by phosphorus. The results of this study provide data support for the response of forest soil carbon cycling to global climate change.

    Cited by
Get Citation
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
  • Received:August 23,2023
  • Revised:October 09,2023
  • Adopted:October 10,2023
  • Online: January 27,2024
  • Published: