Land-use Changes Alter Energy and Water Balances on an African BrachiariaPasture Replacing a Native Savanna in the Orinoco llanos

• DOI: 10.30564/jasr.v2i2.558
• Publication Date: 2019-07-25T23:56:57Z
• Authors: José San José; Rubén Montes; Rafael Herrera; Jair M. Maia; Nina Nikonova
• Keywords: Brachiaria; Herbaceous plant; Dry season; Bowen ratio; Canopy conductance

The seasonal changes in the energy balance after substitution of a herbaceous savanna by Brachiaria field located Orinoco lowlands were assessed over an entire year using eddy covariance technique. Simultaneously, was monitored as control. This work provides evidence that vegetation replacement lead to different patterns and water balance. trends latent heat flux (λE) available (Ra) ratio tended decrease senescence increased due influence air humidity mole fraction deficit soil content on leaf area index (LAI) surface conductance (gs). Therefore, partitioning depended both climatological (i.e., solar radiation, volumetric deficit) biological variables behavior LAI) which stress-induced. For wet season, seasonally averaged daily λE 0.8 ± 0.1 mm d-1) 1.3-fold higher than 0.6 (Mann-Whitney U-test). dry value 2.7 2.2 0.4 d-1, respectively, these means values not significantly different. In stands, annual evapotranspiration 731 594 year-1, precipitation 0.52 0.42 respectively. field, deep drainage relatively lower (43% total precipitation) stand (53%) leaving similar amount increase storage. current shift land cover uptake from pasture with high belowground phytomass LAI.