51 research outputs found
Modeling freshwater quality scenarios with ecosystem-based adaptation in the headwaters of the Cantareira system, Brazil
Although hydrologic models provide hypothesis testing of complex
dynamics occurring at catchments, freshwater quality modeling is
still incipient at many subtropical headwaters. In Brazil, a few
modeling studies assess freshwater nutrients, limiting policies on
hydrologic ecosystem services. This paper aims to compare freshwater
quality scenarios under different land-use and land-cover (LULC) change,
one of them related to ecosystem-based adaptation (EbA), in
Brazilian headwaters. Using the spatially semi-distributed Soil and
Water Assessment Tool (SWAT) model, nitrate, total phosphorous (TP) and
sediment were modeled in catchments ranging from 7.2 to
1037 km2. These headwaters were eligible areas of the
Brazilian payment for ecosystem services (PES) projects in the
Cantareira water supply system, which had supplied water to
9 million people in the São Paulo metropolitan region (SPMR). We considered
SWAT modeling of three LULC scenarios: (i) recent past scenario
(S1), with historical LULC in 1990; (ii) current land-use
scenario (S2), with LULC for the period 2010–2015 with field
validation; and (iii) future land-use scenario with PES
(S2 + EbA). This latter scenario proposed forest cover
restoration through EbA following the river basin plan by
2035. These three LULC scenarios were tested with a selected record
of rainfall and evapotranspiration observed in 2006–2014, with the
occurrence of extreme droughts. To assess hydrologic services, we
proposed the hydrologic service index (HSI), as a new composite
metric comparing water pollution levels (WPL) for reference
catchments, related to the grey water footprint (greyWF) and water
yield. On the one hand, water quality simulations allowed for the
regionalization of greyWF at spatial scales under LULC
scenarios. According to the critical threshold, HSI identified areas
as less or more sustainable catchments. On the other hand,
conservation practices simulated through the S2 + EbA scenario
envisaged not only additional and viable best management practices (BMP),
but also preventive decision-making at the headwaters of water
supply systems.</p
Physical characterization of a watershed through GIS: a study in the Schmidt stream, Brazil
Mapeamento de cianobactérias por meio da fluorescência da ficocianina e de análise geoestatística
Analysis of the phytoplankton community emphasizing cyanobacteria in four cascade reservoirs system of the Iguazu River, Paraná, Brazil
How land use/land cover changes can affect water, flooding and sedimentation in a tropical watershed: a case study using distributed modeling in the Upper Citarum watershed, Indonesia
[EN] Human activity has produced severe LULC changes within the Upper Citarum watershed and these changes are predicted to continue in the future. With an increase in population parallel to a 141% increment in urban areas, a reduction of rice fields and the replacement of forests with cultivations have been found in the past. Accordingly, LCM model was used to forecast the LULC in 2029. A distributed model called TETIS was implemented in the Upper Citarum watershed to assess the impact of the different historical and future LULC scenarios on its water and sediment cycles. This model was calibrated and validated with different LULCs. For the implementation of the sediment sub-model, it was crucial to use the bathymetric information of the reservoir located at the catchment's outlet. Deforestation and urbanization have been shown to be the most influential factors affecting the alteration of the hydrological and sedimentological processes in the Upper Citarum watershed. The change of LULC decreases evapotranspiration and as a direct consequence, the water yield increased by 15% and 40% during the periods 1994-2014 and 2014-2029, respectively. These increments are caused by the rise of three components in the runoff: overland flow, interflow and base flow. Apart from that, these changes in LULC increased the area of non-tolerable erosion from 412 km(2) in 1994 to 499 km(2) in 2029. The mean sediment yield increased from 3.1 Mton -yr(-1) in the 1994 LULC scenario to 6.7 Mton-yr(-1) in the 2029 LULC scenario. An increment of this magnitude will be catastrophic for the operation of the Saguling Dam.This study was partially funded by the Spanish Ministry of Economy and Competitiveness through the research projects TETISMED (CGL2014-58,127-C3-3-R) and TETISCHANGE (RTI2018-093717-B-I00). The authors are also thankful to the Directorate General of Higher Education of Indonesia (DIKTI) for the Ph.D. funding of the first author.Siswanto, SY.; Francés, F. (2019). How land use/land cover changes can affect water, flooding and sedimentation in a tropical watershed: a case study using distributed modeling in the Upper Citarum watershed, Indonesia. Environmental Earth Sciences. 78(17):1-15. https://doi.org/10.1007/s12665-019-8561-0S115781
Avaliação do subleito de rodovias vicinais de baixo volume de tráfego por meio de ensaios geotécnicos
Efeito da taxa de carregamento sobre a remoção de poluentes de esgoto em sistemas alagados construídos
Sistemas de classificações geotécnicas de solos: estudo de caso aplicado à rodovia não pavimentada vcs 346, Viçosa, MG
Structure and dynamics of the community of periphytic algae in a subtropical reservoir (state of São Paulo, Brazil)
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