@Article{PachecoSACRASAO:2015:EfRiIn,
author = "Pacheco, Felipe Siqueira and Soares, M. C. S. and Assireu, A. T.
and Curtarelli, Marcelo Pedroso and Roland, F. and Abril, G. and
Stech, Jos{\'e} Luiz and Alval{\'a}, Plinio Carlos and Ometto,
Jean Pierre Henry Balbaud",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Universidade Federal de Juiz de Fora (UFJF)} and {Universidade
Federal de Itajub{\'a} (UNIFEI)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Universidade Federal de Juiz de
Fora (UFJF)} and {Laboratoire Environnements et
Pal{\'e}oenvironnements Oc{\'e}aniques et Continentaux (EPOC)}
and {Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "The effects of river inflow and retention time on the spatial
heterogeneity of chlorophyll and water–air CO2 fluxes in a
tropical hydropower reservoir",
journal = "Biogeosciences",
year = "2015",
volume = "12",
pages = "147--162",
abstract = "Abundant research has been devoted to understanding the complexity
of the biogeochemical and physical processes that are responsible
for greenhouse gas (GHG) emissions from hydropower reservoirs.
These systems may have spatially complex and heterogeneous GHG
emissions due to flooded biomass, river inflows, primary
production and dam operation. In this study, we investigated the
relationships between the waterair CO2 fluxes and the
phytoplanktonic biomass in the Funil Reservoir, which is an old,
stratified tropical reservoir that exhibits intense phytoplankton
blooms and a low partial pressure of CO2 (pCO2). Our results
indicated that the seasonal and spatial variability of chlorophyll
concentrations (Chl) and pCO2 in the Funil Reservoir are related
more to changes in the river inflow over the year than to
environmental factors such as air temperature and solar radiation.
Field data and hydro\-dynamic simulations revealed that river
inflow contributes to increased heterogeneity during the dry
season due to variations in the reservoir retention time and river
temperature. Contradictory conclusions could be drawn if only
temporal data collected near the dam were considered without
spatial data to represent CO2 fluxes throughout the reservoir.
During periods of high retention, the average CO2 fluxes were 10.3
mmol m\−2 d\−1 based on temporal data near the dam
versus \−7.2 mmol m\−2 d\−1 with spatial data
from along the reservoir surface. In this case, the use of solely
temporal data to calculate CO2 fluxes results in the reservoir
acting as a CO2 source rather than a sink. This finding suggests
that the lack of spatial data in reservoir C budget calculations
can affect regional and global estimates. Our results support the
idea that the Funil Reservoir is a dynamic system where the
hydrodynamics represented by changes in the river inflow and
retention time are potentially a more important force driving both
the Chl and pCO2 spatial variability than the in-system ecological
factors.",
doi = "10.5194/bg-12-147-2015",
url = "http://dx.doi.org/10.5194/bg-12-147-2015",
issn = "1726-4170",
language = "en",
targetfile = "Pacheco_effects.pdf",
urlaccessdate = "28 abr. 2024"
}