Open Access

ARTICLE

Effects of Fertilization on Soil CO₂ Efflux in Chinese Hickory (Carya cathayensis) Stand

Juan Liu^1,2,*, Meiqun Zheng¹, Xueshuang Chen¹

1 Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration, Zhejiang A&F University, Hangzhou, 311300, China
2 State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China

* Corresponding Author: Juan Liu. Email:

(This article belongs to the Special Issue: The Effect of Soil Quality Degradation on the Plant Growth, Quality and Food Safety in Subtropical Agroforestry Ecosystems)

Phyton-International Journal of Experimental Botany 2023, 92(1), 271-283. https://doi.org/10.32604/phyton.2022.023397

Received 24 April 2022; Accepted 20 May 2022; Issue published 06 September 2022

Abstract

Chinese hickory (Carya cathayensis Sarg.) is a popular nut tree in China, but there is little information about the influences of fertilization on soil CO₂ efflux and soil microbial biomass. This study evaluated the short-term effects of different fertilizer applications on soil CO₂ efflux and soil microbial biomass in Chinese hickory stands. Four fertilizer treatments were established: control (CK, no fertilizer), inorganic fertilizer (IF), organic fertilizer (OF), and equal parts organic and inorganic N fertilizers (OIF). A field experiment was conducted to measure soil CO₂ effluxes using closed chamber and gas chromatography techniques. Regardless of the fertilization practices, soil CO₂ effluxes of all the treatments showed a similar temporal pattern, with the highest value in summer and the lowest in winter. The mean annual soil CO₂ efflux in the IF treatment was significantly higher than that in the CK, OIF, and OF treatments. There was no significant difference in soil CO₂ efflux between the OIF, OF, and CK treatments. Soil CO₂ effluxes were significantly affected by soil temperature. Soil dissolved organic carbon (DOC) was positively correlated with soil CO₂ efflux only in the CK treatment. Regression analysis, including soil temperature, moisture, and DOC, showed that soil temperature was the primary factor influencing soil CO₂ effluxes. Both OF and OIF treatments increased concentrations of soil microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN), but decreased the ratio of MBC:MBN. These results reveal that applying organic fertilizer, either alone or combined with inorganic fertilizer, may be the optimal strategy for mitigating soil CO₂ emission and improving soil quality in Chinese hickory stands.

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Keywords

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