Influence of pruning waste biochar and oyster shell on N2O and CO2 emissions from Japanese pear orchard soil

Aung Zaw Oo; Shigeto Sudo; Khin Thuzar Win; Akira Shibata; Takeru Gonai

doi:10.1016/j.heliyon.2018.e00568

Influence of pruning waste biochar and oyster shell on N₂O and CO₂ emissions from Japanese pear orchard soil

Heliyon. 2018 Mar 12;4(3):e00568. doi: 10.1016/j.heliyon.2018.e00568. eCollection 2018 Mar.

Authors

Aung Zaw Oo¹, Shigeto Sudo¹, Khin Thuzar Win², Akira Shibata³, Takeru Gonai⁴

Affiliations

¹ Institute for Agro-Environmental Science (NIAES), National Agriculture and Food Research Organization (NARO), 3-1-3 Kannondai Tsukuba, Ibaraki, 305-8604, Japan.
² Central Regional Agricultural Research Center, National Agriculture and Food Research Organization (NARO), Kannondai 2-1-18, Tsukuba, 305-8666, Japan.
³ Ritsumeikan University OIC Research Organization, 2-150 Iwakura-cho, Ibaraki, Osaka, 567-8570, Japan.
⁴ Horticultural Institute, Ibaraki Agricultural Center, 3165-1 Ago, Kasama, Ibaraki, 319-0292, Japan.

Abstract

Two incubation experiments were conducted under controlled moisture and temperature conditions to determine the effects of soil amendment treatments based on pruning waste biochar and oyster shell, on N₂O and CO₂ emissions from an orchard soil. In experiment 1, four treatments were tested including, control (CK), pruning waste biochar at 2% (B2%), at 10% (B10%), and oyster shell (OS), mixed with soil from two different depths, namely, from the 0-5 cm and the 0-10 cm layers. In experiment 2, only the 0-10 cm soil layer was used to study the effect of surface application of pruning waste biochar (B2% and B10%) on soil N₂O and CO₂ emissions. The results showed that soil pH, total C and C: N ratio increased with biochar amendment treatments. Significant reduction in soil NO₃^- content was observed for the B10% treatment. Although OS application increased soil pH, no effect was observed on soil mineral N content, total C or C: N ratio. The rate of N₂O emissions from the 0-5 cm soil layer after B2% and B10% addition, significantly declined by 12.5% and 26.3%, respectively. However, only the B10% treatment caused significant reduction in N₂O emissions from the 0-10 cm soil layer and from surface soil, by 15.1% and 13.8%, respectively. Oyster shell application had no effect on either soil N₂O or CO₂ emissions from either soil layer tested. Our results suggest that the addition of pruning waste biochar at a high rate has the potential to mitigate N₂O emissions from orchard soils; while, oyster shell can be used for liming without altering soil N₂O nor CO₂ emissions.

Keywords: Agriculture; Earth sciences; Environmental science.