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Nitrogen Saturation, Methane Emission Intensity, and ThermalTurning Points in Intensive Rice Cultivation in the VietnameseMekong Delta |
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| รหัสดีโอไอ | |
| Creator | Vo Nguyen Thien Phuc |
| Title | Nitrogen Saturation, Methane Emission Intensity, and ThermalTurning Points in Intensive Rice Cultivation in the VietnameseMekong Delta |
| Contributor | Tra Van Trung, Nguyen Tuong Chau |
| Publisher | Thai Society of Higher Education Institutes on Environment |
| Publication Year | 2569 |
| Journal Title | EnvironmentAsia |
| Journal Vol. | 19 |
| Journal No. | 3 |
| Page no. | 179-189 |
| Keyword | Nitrogen saturation, Methane emission intensity, Entity fixed effects, Thermalturning point, Mekong Delta rice |
| URL Website | http://www.tshe.org/ea/index.html |
| Website title | EnvironmentAsia |
| ISSN | 1906-1714 |
| Abstract | Intensive lowland rice cultivation in the Vietnamese Mekong Delta (VMD) confronts a persistenttension between yield maintenance and greenhouse gas accumulation. A province-levelpanel with entity fixed effects (1995–2022, 13 VMD provinces, up to 364 province-yearobservations) was constructed from General Statistics Office of Vietnam, Ministry of Agricultureand Rural Development, and IPCC Tier 1 was recorded to examine nitrogen–yield saturation,sub-regional methane (CH4) emission intensity, and a shared thermal turning point. Neither thelinear nor the quadratic term of inorganic nitrogen application (mean = 132.74 kg N/ha) wasassociated with biological yield (327 observations, 12 provinces; p > 0.1), a pattern consistentwith, though not sufficient on its own to confirm, nitrogen saturation. Mean CH4 emissionintensity, after correcting a unit inconsistency in the underlying dataset, is 32.48 kg CH4/tongrain (SD = 7.19; 355 observations). Nitrogen application was positively associated with CH4intensity in the Coastal acid-sulfate sub-region (β = 0.022 kg CH4/ton per kg N/ha, p = 0.008);the additional Inland differential was not statistically distinguishable from zero (p = 0.244).Quadratic temperature terms indicated turning points of 28.15 °C (yield equation; 95% CI27.76–28.53) and 28.11°C (CH4 equation; 95% CI 27.75–28.47), with overlapping confidenceintervals. These findings offered a cautious, delta-scale empirical reference for nitrogen andthermal-risk management discussions in comparable Southeast Asian lowland paddy systems. |
