Chinese Journal OF Rice Science ›› 2021, Vol. 35 ›› Issue (1): 78-88.DOI: 10.16819/j.1001-7216.2021.0509

• Research Papers • Previous Articles     Next Articles

Effects of Tillage Methods on Distribution Characteristics of CH4 and N2O in Soil Profile ofDouble-cropping PaddyField

Tong YANG, Junnan WU, Ting BAO, Fengbo LI, Jinfei FENG, Xiyue ZHOU, Fuping FANG*()   

  1. China National Rice Research Institute, Hangzhou 311401, China
  • Received:2020-05-12 Revised:2020-06-08 Online:2021-01-10 Published:2021-01-10
  • Contact: Fuping FANG

耕作方式对双季稻田土壤剖面CH4和N2O分布特征的影响

杨通, 吴俊男, 鲍婷, 李凤博, 冯金飞, 周锡跃, 方福平*()   

  1. 中国水稻研究所,杭州 311401
  • 通讯作者: 方福平
  • 基金资助:
    国家重点研发计划资助项目(2016YFD0300906)

Abstract:

【Objective】Exploring the spatial and temporal variation of the concentrations of CH4 and N2O in soil profile is beneficial to understanding the mechanism behind the effects of agronomic measures on the production and diffusion of greenhouse gas from paddy fields.【Method】A field experiment with different tillage treatments [rotary tillage (RT) and no tillage (NT)] and fertilization measures, including no fertilization (CK), only chemical fertilizer (F), and fertilizer + straw returning (FS), was conducted to reveal the distribution characteristics of CH4 and N2O in the surface water and soil profile.【Result】The concentration of CH4 in the surface water in the early and late rice growing seasons was significantly lower than that in the soil profile. On the contrary, the concentration of N2O in the surface water was higher than that in the soil profile. The concentration of CH4 in the soil profile decreased with the increase of soil depth. Whereas no obvious trend was observed for N2O in the soil profile. Tillage methods significantly affected the concentrations of CH4 and N2O in the soil profile. RT significantly increased the concentration of CH4, especially in 0-5 cm and 5-10 cm soil layers, while significantly reduced the concentration of N2O in the soil profile at some growth periods, as compared with NT. The correlation indexes between net CH4 flux rate and CH4concentration in upper soil layers was higher than that in the deep soil layers and field surface water. The net flux rate of N2O in the early rice growing season was primarily affected by the concentration of N2O in the surface soil layer; while the net flux rate of N2O in the late rice growing season was mainly affected by the concentration of N2O in the middle and deep soil layers.【Conclusion】The concentrations of CH4 and N2O in soil profile presented great spatial-temporal variation during the early and late rice growing seasons. Tillage method significantly affected the concentrations of CH4 and N2O in soil profile.

Key words: double cropping rice, soil profile, temporal and spatial distribution, greenhouse gas, soil surface water

摘要: 目的 探明双季稻稻田土壤剖面CH4和N2O的时空分布特征,有利于揭示农艺措施对稻田土壤温室气体产生和排放过程的作用机制。方法通过小区试验,研究了旋耕(RT)和免耕(NT)在不同培肥措施[不施肥(CK)、仅施化肥(F)、化肥+秸秆还田(FS)]下对双季稻主要生育期田面水和土壤剖面CH4和N2O分布特征的影响。结果 早晚稻季田面水CH4浓度显著低于土壤剖面CH4浓度;而田面水N2O浓度高于土壤剖面N2O浓度。土壤剖面CH4浓度随深度增加而下降;而N2O浓度在土壤剖面中无显著变化。耕作方式对土壤剖面CH4和N2O浓度存在显著效应。与NT相比,RT显著增加了土壤剖面CH4浓度,尤其是0-5 cm和5-10 cm土层;而在部分生育期显著降低土壤剖面N2O浓度。早晚稻季CH4净排放通量与上层土壤CH4浓度相关性高于下层土壤和田面水。表层土壤是影响早稻季N2O排放的主要因素,而中下层土壤是影响晚稻季N2O排放的主要因素。结论 双季稻田土壤剖面CH4和N2O具有明显的时空变化特征,而耕作方式对其浓度具有显著影响。

关键词: 双季稻, 土壤剖面, 时空分布, 温室气体, 田面水