A Year-Round Study of Water Vapor, Energy and Net Ecosystem Exchanges in a Young Oil Palm Field in Dangbo, Bénin

Abstract

In 2022, an eddy covariance site was established in a young oil palm plantation in southeast Dangbo, Bénin, to study the exchange of CO 2 , energy, and water vapor. This study aims to present the first one-year analysis of seasonal dynamics in energy balance components and net ecosystem exchange above this type of ecosystem in Africa. The first results show that on average during the 2023 year, 55% of net radiation is consumed into actual evapotranspiration, demonstrating the significant amount of latent heat flux in the energy balance, as expected at this tropical humid site. The sensible heat flux was substantial, ranging between 60 and 200 W·m −2 , while net radiation varied between 440 and 650 W·m −2 . Carbon uptake and net release of CO 2 into the atmosphere were permanent at the site. However, the CO 2 uptake increases more when rainy events become regular. On average, the mean nighttime CO 2 flux was ~8 µmol·m − 2 ·s − 1 , while during the daytime it was ~−20 µmol·m − 2 ·s − 1 .