Water vapor flux in tropical lowland rice

• Published in: Environmental monitoring and assessment 2019-09, Vol.191 (9), p.550-550, Article 550
• Main Authors: Chatterjee, Dibyendu, Nayak, Amaresh Kumar, Vijayakumar, S., Debnath, Manish, Chatterjee, Sumanta, Swain, Chinmaya Kumar, Bihari, Priyanka, Mohanty, S., Tripathi, Rahul, Shahid, Mohammad, Kumar, Anjani, Pathak, H.
• Format: Article
• Language: English
• Subjects: Agricultural research; Agriculture; Air temperature; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon Cycle - physiology; Carbon dioxide; Carbon Dioxide - analysis; Carbon dioxide flux; Climate change; Correlation coefficient; Correlation coefficients; Covariance; Diurnal; Diurnal variations; Dry season; Earth and Environmental Science; Ecology; Ecosystem; Ecotoxicology; Eddy covariance; Environment; Environmental Management; Environmental monitoring; Environmental Monitoring - methods; Environmental science; Evaporation; Flowering; Fluctuations; Heat; Heat flux; Heat of vaporization; Heat transfer; India; Latent heat; Latent heat flux; Minimum temperatures; Monitoring/Environmental Analysis; Net radiation; Oryza - chemistry; Principal Component Analysis; Principal components analysis; Radiation; Radiation balance; Radiation flux; Relative humidity; Seasons; Short wave radiation; Soil; Soil - chemistry; Soil temperature; Soil water; Soils; Steam - analysis; Temperature; Tropical climate; Vapor pressure; Vaporization; Vaporization heat; Vapour pressure; Water - chemistry; Water temperature; Water vapor; Water vapor flux; Water vapour
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-019-7709-4

A field experiment was conducted at Indian Council of Agricultural Research-National Rice Research Institute, Cuttack, Odisha, India in the dry seasons of 2015 and 2016 to assess the water vapor flux (FH 2 O) and its relationship with other climatic variables. The FH 2 O and climatic variables were measured by an eddy covariance system and a micrometeorological observatory. Daily mean FH 2 O during the dry seasons of 2015 and 2016 were 0.009–0.092 g m −2 s −1 and 0.014–0.101 g m −2 s −1 , respectively. Seasonal average FH 2 O was 14.6% higher in 2016 than that in 2015. Diurnal variation for FH 2 O showed a bell-shaped curve with its peak at 13:30–14:00 Indian Standard Time (IST) in both the years. Carbon dioxide flux was found higher with rise in FH 2 O. This relationship was stronger at higher vapor pressure deficit (VPD) (20 ≤ VPD ≤ 40 and VPD > 40 hPa). The FH 2 O showed significant positive correlation with latent heat flux, net radiation flux, photosynthatically active radiation, air, water and soil temperatures, shortwave down and upwell radiations, maximum and minimum temperatures, evaporation, and relative humidity in both the years. Principal component analysis showed that FH 2 O was very close to latent heat flux in both the years (Pearson correlation coefficient close to 1). The two-dimensional observation map of the principal component F1 and F2 showed the observations taken during the vegetative stage and panicle initiation stage, and flowering stage and maturity stage were closer to each other. It can be concluded that the most important climatic variables controlling the FH 2 O were latent heat of vaporization, net radiation, air temperature, soil temperatures, and water temperature.