Work

Phenology-resolved dynamics of rice growth and methane emissions across transplanting dates and cultivars using logistic models

Year: 2026

Type: article

Abstract: Methane (CH 4 ) emissions from flooded paddy soils are closely linked to rice growth, yet this relationship is commonly evaluated using seasonal totals rather than dynamic growth–emission indicators. This study applied three-parameter logistic models to characterize phenology-associated rice growth and CH 4 accumulation under four transplanting dates in a continuously flooded paddy field. Koshihikari, an early- to medium-maturing cultivar, and Chamdream, a medium- to late-maturing cultivar, were evaluated for plant growth, grain yield, and CH 4 emissions. Logistic parameters describing asymptotic magnitude (L), inflection timing (x 0 ), rate (k), and time to 90% accumulation (t 90 ) were derived. Delayed transplanting shortened the transplanting-to-heading period and compressed crop development without a significant yield penalty. Compared with the May transplantings, the June transplantings reduced both observed seasonal CH 4 emissions and fitted asymptotes by approximately one-half, resulting in similarly lower CH 4 -based global warming potential and greenhouse gas intensity. Logistic models accurately described cumulative CH 4 emissions (R 2 =0.993–0.999; NRMSE = 2.56–5.60%). Delayed transplanting advanced CH 4 x0 by 19–36 d in Koshihikari and 16–37 d in Chamdream and shortened t 90 by 35–55 and 26–65 d, respectively, indicating earlier and more compressed CH 4 accumulation. Positive associations between aboveground biomass and cumulative CH 4 emissions remained significant after adjustment for days after transplanting. These findings show that crop-calendar adjustment can reduce CH 4 intensity under continuous flooding and that logistic timing indices can complement seasonal totals for phenology-based monitoring and emission-factor refinement.

Source: Smart Agricultural Technology

DOI: 10.1016/j.atech.2026.102514

Authors: Yong-Seon Lee, Tae-Il Moon, A-Rin Kim, Sunghoon Kim, Hyun-Hwoi Ku

Institutions: Hankyong National University, National Institute of Environmental Research

Language: English

Topic: Rice Cultivation and Yield Improvement

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Climate action, Zero hunger

Open Access status: gold

Estimated APC paid: $1,770