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1.
Sci Total Environ ; 788: 147762, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34022571

RESUMEN

River flow characterizes the integrated response from watersheds, so it is essential to quantify to understand the changing water cycle and underpin the sustainable management of freshwaters. However, river gauging stations are in decline with ground-based observation networks shrinking. This study proposes a novel approach of estimating river flows using the Planet CubeSats constellation with the possibility to monitor on a daily basis at the sub-catchment scale through remote sensing. The methodology relates the river discharge to the water area that is extracted from the satellite image analysis. As a testbed, a series of Surface Reflectance PlanetScope images and observed streamflow data in Araguaia River (Brazil) were selected to develop and validate the methodology. The study involved the following steps: (1) survey of measurements of water level and river discharge using in-situ data from gauge-based Conventional Station (CS) and measurements of altimetry using remote data from JASON-2 Virtual Station (JVS); (2) survey of Planet CubeSat images for dates in step 1 and without cloud cover; (3) image preparation including clipping based on different buffer areas and calculation of the Normalized Difference Vegetation Index (NDVI) per image; (4) water bodies areas calculation inside buffers in the Planet CubeSat images; and (5) correlation analysis of CubeSat water bodies areas with JVS and CS data. Significant correlations between the water bodies areas with JVS (R2 = 88.83%) and CS (R2 = 96.49%) were found, indicating that CubeSat images can be used as a CubeSat Virtual Station (CVS) to estimate the river flow. This newly proposed methodology using CubeSats allows for more accurate results than the JVS-based method used by the Brazilian National Water Agency (ANA) at present. Moreover, CVS requires small areas of remote sensing data to estimate with high accuracy the river flow and the height variation of the water in different timeframes. This method can be used to monitor sub-basin scale discharge and to improve water management, particularly in developing countries where the presence of conventional stations is often very limited.

2.
Environ Monit Assess ; 190(9): 511, 2018 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-30097732

RESUMEN

The Serra do Mar State Park forms a green corridor that connects significant remnants of the Atlantic Forest in Brazil, a region that presents great biodiversity. However, the mounting pressure exerted on it by disorderly urban expansion around conservation unit areas is a cause for concern. Thereby, this paper aims to analyze a geographical and demographic characterization of Serra do Mar State Park and its buffer zone in order to identify regions under the greatest pressure and provide subsidies for developing public policies. The study is based on a cartographic representation using a geographic information system associated with the 2010 Census demographic data, which has been conducted by the Brazilian Institute of Geography and Statistics (IBGE in Portuguese acronym). The study area covers the territory of 32 municipalities and it was found that almost 25,000 inhabitants live inside the park while approximately 712,000 residents live inside its buffer zone.


Asunto(s)
Conservación de los Recursos Naturales , Demografía , Monitoreo del Ambiente , Animales , Biodiversidad , Brasil , Bosques , Sistemas de Información Geográfica , Geografía
3.
Eng. sanit. ambient ; 19(4): 461-470, Oct-Dec/2014. tab, graf
Artículo en Portugués | LILACS | ID: lil-735878

RESUMEN

O elevado consumo de combustíveis e sua inadequada disposição no passado geraram preocupações com a poluição do solo e de aquíferos. Essas preocupações tornaram-se ainda maiores pela necessidade de exploração de aquíferos para atender à crescente demanda por recursos hídricos. Este trabalho teve como objetivo avaliar a eficiência e a eficácia da técnica de bombeamento e tratamento aplicada à remediação da pluma de fase livre de hidrocarbonetos na área do Auto Posto Baía do Sol, localizado em São Sebastião, no litoral norte do estado de São Paulo, sobre o Aquífero Sedimentar Litorâneo. Os resultados demonstraram que a técnica de bombeamento e tratamento foi eficiente na remediação da área deste Auto Posto, com a remoção total dos poluentes em fase livre. Por outro lado, a técnica apresentou baixa eficácia em razão da necessidade de um período prolongado de bombeamento.


High fuel consumption and its inadequate control in fuel stations caused the pollution of soil and aquifers. These consequences created more concern with the increased exploration of aquifers to supply the groundwater demand. The objective of this study was to evaluate the eficiency and efectiveness of the of pump and treat technique of the water applied to the Coastal Aquifer in the cleaning up of the plumes produced by the leaking of fuel in the gas station Auto Posto Baía do Sol Ltda. The gas station is located in São Sebastião, in the north coast of São Paulo State. In the case of Auto Posto Baía do Sol Ltda., the technique of pump and treat was eficient and the plume produced by the leakage was completely removed. However, the efectiveness of this technique was low due to the long time required for the complete operation.

4.
Biota neotrop. (Online, Ed. port.) ; 6(2): 0-0, 2006. mapas, tab
Artículo en Portugués | LILACS | ID: lil-447592

RESUMEN

A Reserva Florestal do Morro Grande (RFMG, 10.870 ha) é um dos maiores remanescentes florestais do Planalto Atlântico paulista, região que foi submetida a fortes pressões de desmatamento tanto para a agricultura quanto para a exploração da lenha e do carvão e, mais recentemente, para a expansão imobiliária. A RFMG situa-se sobre embasamento cristalino, justo acima da Serra de Paranapiacaba, em altitudes que variam de 860 a 1075 m, numa região de transição entre o clima pluvial tropical do litoral e da encosta Atlântica, com o clima estacional do interior do estado. Por conseguinte, suas florestas acabam tendo uma composição de espécies particular, com elementos das florestas ombrófila densa e mesófila semi-decidual. Apesar desta particularidade, não houve até recentemente praticamente nenhum estudo nas florestas do Morro Grande. Foi apenas a partir de 2000 que um grupo de pesquisadores, no contexto de um projeto temático vinculado ao programa BIOTA/FAPESP, procurou analisar de forma sistemática a composição de diferentes grupos taxonômicos, assim como caracterizar processos ecológicos associados com a regeneração florestal. Este artigo tem por objetivo introduzir uma série de nove artigos com os principais resultados dos levantamentos biológicos na RFMG, obtidos nos últimos quatro anos, assim como fazer uma caracterização do histórico e das condições abióticas na Reserva, em termos de embasamento geológico, pedológico, clima, hidrografia, e do uso e cobertura do território.


The Morro Grande Forest Reserve (10,870 ha) is one of the biggest forest areas in the Atlantic Plateau. This region was intensively deforested for agriculture, wood and charcoal production, and more recently by the expansion of urban areas. The Reserve is located in the cristalline Plateau of Ibiúna, just above the Paranapiacaba Mountain (860 1075 m above sea level), in a transition region between the rainy climate from the Atlantic coast, and the seasonal climate from inland São Paulo state. As a consequence, species composition in Morro Grande Reserve combines elements from the tropical rainforest and the semideciduous forest. Despite this particularity, few studies were carried out in the forests from Morro Grande. It is only in 2000 that a group of scientist related to the BIOTA/FAPESP program began a systematic analysis of the species composition of different taxonomic groups, as well as the analysis of ecological processes related with forest regeneration. The present manuscript introduces a series of nine articles with the biological data obtained in the Reserve these last four years, and aims also to present an historical and abiotic description of the Reserve, highlighting aspects of the relief, geologic and pedological conditions, climate, hydrography, land use and land cover.


Asunto(s)
Conservación de los Recursos Naturales/análisis , Conservación de los Recursos Naturales/efectos adversos , Ecología/clasificación , Ecología/educación , Flora/análisis , Flora/efectos adversos
5.
Auton Neurosci ; 112(1-2): 31-6, 2004 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-15233928

RESUMEN

We determined the effects of moxonidine and rilmenidine 20 nmol (alpha(2)-adrenergic and imidazoline receptor agonists) injected into the medial septal area (MSA) on the pilocarpine-induced salivation, when injected intraperitoneally (i.p.), of male Holtzman rats weighing 250-300 g, with stainless-steel cannula implanted into the MSA. The rats were anesthetized with zoletil 50 mg kg(-1) b.wt. (tiletamine chloridrate 125.0 mg and zolazepan chloridrate 125.0 mg) into quadriceps muscle intramuscularly (IM), saliva was collected using pre-weighed small cotton balls inserted in the animal's mouth. The pre-treatment with moxonidine injected into the MSA reduced the salivation induced by pilocarpine (1 mg kg(-1)) injected i.p. (12+/-3 mg min(-1)) vs. control (99+/-9 mg min(-1)). The pre-treatment with rilmenidine 40 nmol also reduced the salivation induce by pilocarpine injected i.p. (20+/-5 mg min(-1)) vs. control (94+/-7 mg min(-1)). Idazoxan 40 nmol (imidazoline receptor antagonist) injected into the MSA previous to moxonidine and rilmenidine partially blocked the effect of moxonidine and totally blocked the rilmenidine effect in pilocarpine-induced salivation injected i.p. (60+/-8 and 95+/-10 mg min(-1), respectively). Yohimbine 40 nmol (alpha(2)-adrenergic receptor antagonist) injected into the MSA previously to moxonidine and rilmenidine partially blocked the moxonidine effect but produced no change on the rilmenidine effect on i.p. pilocarpine-induced salivation (70+/-6 and 24+/-6 mg min(-1), respectively). Injection of these alpha(2)-adrenergic and imidazoline agonists and antagonists agents i.p. produced no change on i.p. pilocarpine-induced salivation. These results show that central, but not peripheral, injection of alpha(2)-adrenergic and imidazoline agonists' agents inhibit pilocarpine-induced salivation. Idazoxan, an imidazoline receptor antagonist, totally inhibits the rilmenidine effect and partially inhibits the moxonidine effect on pilocarpine-induced salivation. Yohimbine produced no change on rilmenidine effect but partially inhibited the moxonidine effect. Both of these antagonists when injected into the MSA previous to pilocarpine i.p. potentiated the sialogogue effect of pilocarpine. The results suggest that alpha(2)-adrenergic/imidazoline receptor of the MSA when stimulated blocked pilocarpine-induced salivation in rats when injected intraperitonially. These receptors of the medial septal area have an inhibitory mechanism on salivary secretion.


Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Imidazoles/farmacología , Oxazoles/farmacología , Pilocarpina/toxicidad , Salivación/efectos de los fármacos , Antagonistas Adrenérgicos alfa/farmacología , Análisis de Varianza , Animales , Interacciones Farmacológicas , Idazoxan/farmacología , Masculino , Agonistas Muscarínicos/toxicidad , Ratas , Ratas Sprague-Dawley , Rilmenidina , Tabique del Cerebro/efectos de los fármacos , Yohimbina/farmacología
6.
Auton Neurosci ; 111(1): 66-70, 2004 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-15109940

RESUMEN

In this study we investigated the influence of d(CH2)5-Tyr(Me)-[Arg8]vasopressin (AAVP) and [adamanteanacetyl1,0-ET-d-Tyr2,Val4,aminobutyryl6,Arg8,9]-[Arg8]vasopressin (ATAVP), which are antagonists of vasopressin V1 and V2 receptors, and the effects of losartan, a selective angiotensin AT1 receptor antagonist, and CGP42112A, a selective AT2 receptor antagonist, injected into the lateral septal area (LSA) on thirst and hypertension induced by [Arg8]vasopressin (AVP). AAVP and ATAVP injected into the LSA reduced the drinking responses elicited by injecting AVP into the LSA. Both the AT1 and AT2 ligands administered into the LSA elicited a concentration-dependent decrease in the water intake induced by AVP injected into the LSA, but losartan was more effective than CGP42112A. The increase in MAP, due to injection of AVP into the LSA, was reduced by prior injection of AAVP from 18 +/- 1 to 6 +/- 1 mm Hg. Losartan injected into the LSA prior to AVP reduced the increase in MAP to 7 +/- 0.8 mm Hg. ATAVP and CGP42112A produced no changes in the pressor effect of AVP. These results suggest that the dipsogenic effects induced by injecting AVP into the LSA were mediated primarily by AT1 receptors. However, doses of losartan were more effective when combined with CGP42112A than when given alone, suggesting that the thirst induced by AVP injections into LSA may involve activation of multiple AVP and angiotensin II receptor subtypes. The pressor response of AVP was reduced by losartan and by AAVP. CGP42112A and ATAVP did not change the AVP pressor response. These results suggest that facilitator effects of AVP on water intake are mediated through the activation of V1 receptors and that the inhibitory effect requires V2 receptors. The involvement of AT1 and AT2 receptors can be postulated. Based on the present findings, we suggest that the AVP in the LSA may play a role in the control of water and arterial blood pressure balance.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Tabique del Cerebro/efectos de los fármacos , Vasoconstrictores/administración & dosificación , Vasopresinas/administración & dosificación , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Antihipertensivos/administración & dosificación , Presión Sanguínea/fisiología , Relación Dosis-Respuesta a Droga , Ingestión de Líquidos/fisiología , Inyecciones Intraventriculares , Losartán/administración & dosificación , Masculino , Oligopéptidos/farmacología , Ratas , Receptores de Angiotensina
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