ABSTRACT

Conventional tillage (CT) degrades soil and environmental quality in many major cropping systems. Conservation agriculture, like reduced tillage, can play an important role in maintaining soil organic carbon (SOC) storage and in minimizing greenhouse gas (GHG) emissions from crop fields. An experiment was conducted at the Bangladesh Agricultural Research Institute (BARI), Gazipur to evaluate GHG emission, global warming potential (GWP), GHG intensity and net SOC variations in rice-mustard-rice cropping systems under CT and strip tillage (ST). The emissions of nitrous oxide (N₂O) and carbon dioxide (CO₂) varied significantly because of CT and ST tillage practices. The ST reduced 24–47% methane (CH₄) emission factor, 20–32% CH₄ flux, 32–46% GHG intensity and 31–47% GWP than CT practice. In mustard crop, ST reduced 55–61% of GHG intensity and 52–58% of GWP compared to CT. There was about 33% increase in N₂O emission and 24% augmentation of soil respiratory CO₂ with ST compared to CT. About 8% absorption of net ecosystem CO₂, 9–11% of net SOC and 10% of rice equivalent yields increased in ST compared to CT. It is concluded that ST can minimize soil C loss, improve net ecosystem CO₂ absorption, and reduce GHG intensity, GWP under rice-mustard-rice systems in Asian countries.

摘要

在许多主要种植系统中，传统耕作 (CT) 会降低土壤和环境质量。保护性农业，如减少耕作，可以在维持土壤有机碳 (SOC) 储存和减少农田温室气体 (GHG) 排放方面发挥重要作用。位于加兹普尔的孟加拉国农业研究所 (BARI) 进行了一项实验，以评估 CT 和条带耕作 (ST) 下水稻-芥菜-水稻种植系统的温室气体排放、全球变暖潜能值 (GWP)、温室气体强度和净 SOC 变化。_{一氧化二氮 (N 2} O) 和二氧化碳 (CO ₂ )的排放量因 CT 和 ST 耕作方式而显着不同。ST 减少了 24–47% 甲烷 (CH ₄ ) 排放因子，20–32% CH ₄通量、32-46% 的 GHG 强度和 31-47% 的 GWP 比 CT 实践。在芥菜作物中，与 CT 相比，ST 减少了 55-61% 的 GHG 强度和 52-58% 的 GWP。与 CT 相比，ST 的N ₂ O 排放增加了约 33% ，土壤呼吸 CO ₂增加了 24% 。与 CT 相比，ST 增加了大约 8% 的净生态系统 CO _{2吸收、9-11% 的净 SOC 和 10% 的水稻当量产量。}得出的结论是，在亚洲国家的水稻-芥菜-水稻系统下，ST 可以最大限度地减少土壤碳损失，提高生态系统 CO _{2净吸收量，并降低温室气体强度和全球升温潜能值。}