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The Amazon rainforest is an important source of evapotranspiration and is essential in the global atmospheric circulation and hydrological cycle. However, measurements on vegetated surfaces are difficult, and methods such as remote sensing are promising in the micrometeorological data area. We aimed to assess the applicability of the MOD16 product to estimate evapotranspiration in a vegetated area. MOD16 data (LEMOD) derive from the Moderate Resolution Imaging Spectroradiometer sensor. For comparison, we used data from the eddy covariance system (LEEC) of the tower of the Large-scale Biosphere-Atmosphere Program in the Amazon of the Jaru Biological Reserve. To measure the linearity among variables, the Pearson correlation test (α=0.05) was used, and the T test was applied to assess the statistical significance between LEMOD and LEEC means (α=0.05); the root mean square error was also calculated. Regarding LEMOD, a similarity was found between the annual means of model and data, in which the best LEMOD estimates were obtained for annual averaging, when mean values were 96.51 W m–2 (0.7% lower than LEEC). LEMOD overestimates ranged from 1.05 W m–2 (1%) in 2007 to 15.78 W m–2 (18%) in 2005. Variations in short periods were not represented by the LEMOD product.

The Amazon basin, with a drainage area of about 6 million km2, is the largest drainage basin in the world, consequently the accurate measuring the rainfall dynamics at high spatial and temporal resolution is essential for a better understanding of the hydrological cycle. So, we validated rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) satellite using surface precipitation data collected from 2004 to 2012. Rainfall data came from the Jaru Biological Reserve meteorological station, located to the east in the state of Rondônia, Brazil, and was compared with the estimates of the algorithms 3B42 V7 and 3B43 V7 of the product TRMM. Statistical analysis was based on indices of continuous variables such as the Spearman correlation coefficient (ρ), the square root mean square error normalized by the mean of the observed values ​​(NRMSE), the mean square error (RMSE), the error (ERV) and some categorical indices such as probability of detection (POD), False Alarm (FAR) and success rate (CSI) between the daily and monthly precipitation observed data and the estimated precipitation data. The 3B43 V7 precipitation estimates were broadly representative of surface observations, but underestimated precipitation in the wet season and overestimated precipitation in the dry season. The 3B42 V7 product performed poorly and does not generate a robust representation of surface precipitation.

Small hydroelectric power (SHP) facilities are proliferating around the world, including in Brazil where legislation encourages SHP over other hydropower development, defining SHP as facilities with installed capacities of 3–30 MW and reservoirs

Este trabalho avalia a aplicabilidade dos instrumentos legais de “Outorga” e “Enquadramento” ao setor de saneamento no perímetro urbano da bacia do rio Coxipó, município de Cuiabá/MT, para viabilizar um planejamento estratégico para regularização dos usos, controle da poluição e futura gestão. A proposta foi baseada em um diagnóstico da qualidade de água e das vazões atuais na bacia e um levantamento dos principais usuários e suas demandas. Os mananciais no perímetro urbano mostram uma deterioração da qualidade da água com extrapolação dos limites dados pela Resolução CONAMA 357/2005 para classe 02, principalmente dos parâmetros Fósforo, com valores medianos de até 0,20 mg.L-1, e de Escherichia coli que atingiu medianos acima de 8.000 NMP.100-1 ml, impossibilitando a concessão ou renovação de qualquer Outorga sob as premissas da legislação ambiental vigente. Assumindo como base os limites da Resolução CONAMA para classe 03 e considerando o uso preponderante mais restritivo na bacia é formulada uma proposta de enquadramento transitório para trechos do rio Coxipó, de forma a permitir a regularização do uso para saneamento público.

There are 104 hydroelectric facilities proposed to be installed in the watersheds that feed the Pantanal, a vast floodplain wetland located mostly in Brazil. The Pantanal is host to 23 long‐distance migratory fish species that ascend upland tributaries to spawn. A Geographic Information System was used to predict the impact of hydroelectric dams on potential migration routes for these species. Both anthropogenic (hydroelectric dams) and natural barriers were included in the analysis. Natural barriers were identified by river slope. Critical river slopes of 10 and 25%, above which fish were predicted to be incapable of ascending, were modeled as natural barriers. Based on this model, we show that between 2 and 14% of rivers in the Pantanal watershed are naturally blocked to fish migration. An additional 5 to 9% of rivers are currently blocked due to 35 existing hydroelectric facilities. If all proposed dams are built, the area flooded by new reservoirs will triple and the river kilometers blocked will double, blocking 25 to 32% of the river system to fish migration. The Taquari and Cuiaba River sub‐basins will be the most impacted, each having more than 70% of their rivers blocked. The impact of individual proposed facilities on the loss of migration routes is related to their proximity to existing barriers. Fourteen of the proposed dams are upstream from existing barriers and will therefore not further restrict long‐distance fish migration routes while proposed dams are predicted to close an additional 11,000 to 12,000 km of river channels.

Hydroelectric facilities often release water at variable rates over the day to match electricity demand, resulting in short-term variability in downstream discharge and water levels. This sub-daily variability, known as hydropeaking, has mostly been studied at large facilities. The ongoing global proliferation of small hydropower (SHP) facilities, which in Brazil are defined as having installed capacities between 5 and 30 MW, raises the question of how these facilities may alter downstream flow regimes by hydropeaking. This study examines the individual and cumulative effects of hydropower facilities on tributaries in the upland watershed of the Pantanal, a vast floodplain wetland system located on the upper Paraguay River, mostly in Brazil. Simultaneous hourly discharge measurements from publicly available reference and downstream gage stations were analyzed for 11 reaches containing 24 hydropower facilities. Most of the facilities are SHPs and half are run-of-river designs, often with diversion channels (headraces). Comparison of daily data over an annual period, summarized by indicators of hydrological alteration (HA) that describe the magnitude, frequency, rate of change, and duration of flows, revealed differences at sub-daily scales attributable to hydropeaking by the hydropower facilities. Results showed statistically significant sub-daily HA in all 11 reaches containing hydropower facilities in all months. Discharge indicators that showed the highest percentage of days with increased variability were the mean rates of rise and fall, amplitude, duration of high pulses, maximum discharge, and number of reversals. Those that showed higher percentages of decreased variability included minimum discharge, number of high pulses, duration of stability, and number of low pulses. There was no correlation between HA values and physical characteristics of rivers or hydropower facilities (including installed capacity), and reaches with multiple facilities did not differ in HA from those with single facilities. This study demonstrates that SHPs as well as larger hydropower facilities cause hydrological alterations attributable to hydropeaking. Considering the rapid expansion of SHPs in tropical river systems, there is an urgent need to understand whether the ecological impacts of hydropeaking documented in temperate biomes also apply to these systems.

This work aims to evaluate the hydrologic changes caused by a small hydropower plant on the watercourse in which it is installed. Since hydrologic research with data of temporal frequencies less than a day is less common than daily measurements, there are few indicators and methodologies capable of treating such records. For this reason, 17 indicators are proposed which describe the magnitude, duration, frequency and rate of changes in hydrologic conditions occurring in a watercourse at a sub-daily frequency. These 17 indicators were used to assess changes in the flow regimes at sub-daily scales across the Itiquira hydroelectric facility in Mato Grosso, Brazil. During the dry season the river was more susceptible to hydroelectric operations than during the wet season. Eighty-eight percent of the proposed indicators were significantly altered during the dry season compared to 71% during the rainy season. In addition to the number of indicators that changed between the seasons, the magnitude of the change was different. During the dry season, 53% of the magnitudes of the proposed indicators were classified as having a high magnitude of change, while in the rainy season only 6% of the indicators were characterized as having a high magnitude of change.

This study is an exploratory, spatio-temporal analysis of river discharge in the upper Teles Pires contribution area for the period between 1993 and 2006, and its relationship with deforestation dynamics on a watershed scale. After an evaluation of temporal variability of monthly rainfall and runoff time series, generalized linear models (GLM) have been fitted to examine the relationships between discharge with indicators of deforestation in the contribution area of six sub-watersheds. Monthly discharges at the main outlet show a significant positive trend, whereas increase of precipitation has no statistical significance. Besides precipitation, principal determinant of specific discharge, deforestation percentages and the annual relative rates of deforestation are significant predictors in the three smaller sub-basins with areas up to about 14.000 km 2 . In the most altered sub-basin under intensive agricultural use, the ratio of residence and hydrological response have positive correlations with deforestation indicators, evidencing the removal of arborous formations diminish evapotranspiration and favor discharge. With increasing contribution areas up to about 54,000 km 2 , the interference of deforestation on discharge and hydrological parameters decrease and precipitation remains the unique significant predictor.

Changes in land use associated with the suppression of native vegetation can greatly alter the landscape configuration, affecting biodiversity and environmental services availability. This study analyzes how changes in land use affect landscape patterns of vegetation remnant over a 10 year period. We quantified spatial landscape patterns throughout a hydrographic basin for the years 2002, 2008, 2010 and 2012, using nine landscape metrics. An indicator of integrity was used to details the transformation processes occurring in the basin that could be used to monitor the impact of landscape changes and its spatial patterning. Results showed that over this decade, extension of farming activities reduced the cover of native vegetation by 4.4%, with grassy-woody savanna, wooded savanna and forested savanna impacted especially strongly. Suppression of vegetation across this period reduced the size of fragments and their connectivity. The landscape fragmentation indicator indicated that the fragmentation pattern varied spatially, with the upland areas along river headwaters, being most fragmented. Areas of floodplains vegetation, belonged to the Pantanal Wetland, although in better integrity states, are the most threatened by current pressures of land use change. An intense recovery program for headwaters and aquifer recharge areas, as well as riparian forests, is recommended to avoid the future depletion of water production. Besides, we also recommend the maintenance and recovering of the connectivity of the current remaining patches of natural vegetation corridors and elaboration of specific laws that incoporate the consolidated scientific knowladge about wetland ecosystem functioning, like the Pantanal.

Water quality time series available for major tropical floodplains commonly have low temporal resolutions and irregular sampling frequencies. Here we examine such data using singular spectrum analysis, a non-parametric time series analysis technique, to assess the typical cyclical variations and long-term trends in upland Cerrado and lowland floodplain reaches of three rivers that are tributaries to the Pantanal in Brazil to evaluate ecological state and impact level, and develop recommendations for improved monitoring of Cerrado–Pantanal river systems. Both upland and lowland reaches have their average water quality cycles linked to a monocyclical hydrological regime. Amplitudes of nutrient concentrations (N, P) and Turbidity are higher in the uplands, whereas cyclical oxygen variations are up to two times higher in the floodplain reaches. SSA showed that trend extraction is possible for parameters with lower intra-annual variations and were found to be partially opposing (oxygen) in upland (negative trend) and floodplain (positive trend) stations. Land use intensification in the uplands is reflected by N concentrations in upland reaches. In the floodplain, the Paraguay river was found under a slight TN enrichment regime of about 0.02 mg L−1 per year between 1995 and 2009. Assuming a fixed budget for institutional water quality monitoring, we recommend a reduction of the 150 registered sampling gauges by environmental agencies in the Brazilian Pantanal and its contribution area, 95 % of them with less than four samples per year, in favor of using the same resources for increased sampling frequency at a smaller number of sites.

Summary Facilities that produce hydroelectricity by diversion of part of the river’s flow, which are often considered to have lower environmental impact than conventional hydropower dams, are being built in large numbers on river systems throughout the world, yet their cumulative impacts are not well understood. This study evaluated the hydrological effects of operation of a diversion hydropower facility on the Correntes River in Brazil (mean discharge 73 m 3 s −1 ), which is potentially important because of the ecological implications for the floodplains of the Pantanal into which it flows. Many similar dams are built or proposed on rivers feeding the Pantanal. The 210-MW facility known as Ponte de Pedra diverts part of the river flow into a diversion channel in a nearly “run-of-river” design. The natural (reconstructed) and regulated (observed) flow regimes were characterized using Indicators of Hydrologic Alteration (IHA) and Flow Duration Curves (FDC). Seven parameters of IHA were significantly altered by the reservoir formation (magnitude of lowest monthly flow, minimum flows of 1, 3 and 7 days, maximum flow of 90 days and counts of high and low pulses). Among these, Principal Components Analysis identified the maximum flow of 90 days and the count of high flow pulses as integrators of hydrological alterations. The FDC showed that the reservoir also changed the seasonal regime of the flows, with greater changes in the lowest flow season. The reduction of river–floodplain connectivity and loss of associated ecosystem services are the major downstream ecological implications of this altered flow regime. To maintain the seasonal flooding regime while meeting the requirements for hydroelectric production, proposed limits for flow regime alterations are up to ±18% in low flow, ±24% in the rising limb and ±22% in high flow and the falling limb, relative to the natural flow. Operational changes to maintain flows with these limits could easily be implemented because the hydrological alterations attributed to the reservoir and operations of its dam are modest compared to seasonal variation in river flow. Without attention to maintaining the natural flow regime, the cumulative effects of diversion hydropower dams like this one will significantly alter the ecohydrology of downstream rivers and floodplains.

Diversion hydroelectric facilities are proliferating worldwide, yet how they alter water quality has seldom been assessed. This study evaluates effects of a nearly “run-of-river” diversion hydropower dam (210 MW capacity) on water quality in the Correntes River, a tributary to the Pantanal floodplain of Brazil. Water quality was analyzed from eight locations before and after reservoir construction. Relative to an upstream reference site, the reservoir significantly decreased turbidity (mean, 38%) and concentrations of total solids (23%), total phosphorus (28%), and nitrate (14%). Most changes occurred in the upstream segment of the reservoir (except for turbidity). Only turbidity and nitrate were affected by reservoir operator control of the hydraulic retention time, which ranged from 7.3 to 21.2 days. Overall, the most consequential changes in downstream water quality may be sediment and associated phosphorus retention, which over the long term could affect channel geomorphology and reduce floodplain biological productivity.

The aim of this study was to understand seasonal variations in the vertical structure of the water column, and to quantify the importance of the physical forces (solar radiation, wind and hydraulic retention time) that control mixing processes in a reservoir bordering the Pantanal floodplain. Samples were taken every three months in the reservoir centre, at four depths, for the measurement of nine physical and chemical water quality parameters. The reservoir presented a long stratification period with complete mixing in winter. The vertical structure showed that, during the stratification period, the upper layers of the reservoir are homogeneous and the physical and chemical composition only changes at greater depths. The wind acting over an extended period is the only factor that significantly influences the vertical structure in the reservoir, giving rise to mixing processes. Moreover, the position of the draw-off point in the upper layer of the reservoir, together with the reservoir depth, enha...

This study aimed to (1) examine the effects of land-use change on the soils of natural Cerrado transformed to common croplands (soybean/cotton/maize rotation and sugarcane) and pasture and (2) indicate how agricultural production affects water quality across a meso-scale catchment. Land conversion caused significant reduction in infiltration rates near the soil surface (0–40 cm depth) of pasture (− 96%) and croplands (− 90% to − 93%). Soil aggregate stability was significantly lower in croplands than in Cerrado and pasture. Topsoil pH and nutrient concentrations were high in croplands and pasture. Soybean crops had extremely high extractable P concentrations (80 mg·kg − 1 ; 9 times greater than the natural background), whereas pasture N levels declined. Nutrient accumulation of N and P did not occur at deeper horizons for any land-use type. Snapshot water sampling showed strong seasonality in water quality parameters. Higher temperature, oxi-reduction potential (ORP), NO 2 − , and very low oxygen concentrations ( − 1 ) and saturation ( − 1 ) PO 4 3 − concentrations were measured during summer. Water quality parameters were affected by agricultural activities at all sampled sub-catchments across the meso-scale catchment, regardless of stream characteristics (stream order, percentage of riparian vegetation, sub-catchment size); thus, no spatial trends were observed. Direct NO 3 − leaching appeared to play a minor role; however, water quality is affected by agricultural non-point sources, due to topsoil fertiliser inputs affecting the entire catchment, from small low order streams to the larger rivers of the modified catchment. In conclusion, land-use conversion has degraded soil physical properties, leaving cropland soils more susceptible to surface erosion with potential lateral nutrient transport to the stream network.

A crescente demanda por recursos hídricos tem obrigado os gestores a criarem mecanismos de controle para garantir a sustentabilidade dos mananciais e gerir conflitos entre usuários. Neste trabalho está exposto o desenvolvimento de um Sistema de Suporte à Decisão baseado em lógica fuzzy e AHP para avaliar os efeitos dos usos múltiplos em bacias hidrográficas sobre a disponibilidade hídrica considerando características quantitativas e qualitativas da água. Possibilita também a geração de cenários para solução de possível conflitos, distribuindo o ônus para manutenção do sistema hidrológico entre usuários projetados e já instalados em uma bacia. Concepção e funcionamento do protótipo e suas saídas são ilustrados. A água é um elemento indispensável para a manutenção da vida e, apesar da sua abundância sobre as superfícies do planeta, somente uma pequena fração de 0,007% da água potável se encontra em rios e lagos de onde é retirada a maior parte para usos consuntivos [USGR, 2016]. A partir de 1980 a captaçaõ mundial de água doce tem aumentado cerca de 1% ao ano, principalmente devido à crescente demanda dos países em desenvolvimento. [UNESCO, 2016].

The Brazilian Cerrado is recognized as one of the most threatened biomes in the world, as the region has experienced a striking change from natural Cerrado vegetation to intense cash crop production. This paper reviews the history of land conversion in the Cerrado and the development of soil properties and water resources under past and ongoing land use. We compared soil and water quality parameters from different land uses considering 80 soil and 18 water studies conducted in different regions across the Cerrado to provide quantitative evidence of soil and water alterations from land use change. Following the conversion of native Cerrado, significant effects on soil pH, bulk density and available P and K for croplands and less-pronounced effects on pastures were evident. Soil total N did not differ between land uses because most of the sites classified as croplands were nitrogen-fixing soybeans, which are not artificially fertilized with N. In contrast, water quality studies showed nitrogen enrichment in agricultural catchments, indicating fertilizer impacts and potential susceptibility to eutrophication. Regardless of the land use, P is widely absent because of the high-fixing capacities of deeply weathered soils and the filtering capacity of riparian vegetation. Pesticides, however, were consistently detected throughout the entire aquatic system. In several case studies, extremely high-peak concentrations exceeded Brazilian and European Union (EU) water quality limits, which were potentially accompanied by serious health implications. Land use intensification is likely to continue, particularly in regions where less annual rainfall and severe droughts are projected in the northeastern and western Cerrado. Thus, the leaching risk and displacement of agrochemicals are expected to increase, particularly because the current legislation has caused a reduction in riparian vegetation. We conclude that land use intensification is likely to seriously limit the Cerrado's future regarding both agricultural productivity and ecosystem stability. Because only limited data are available, we recommend further field studies to understand the interaction between terrestrial and aquatic systems. This study may serve as a valuable database for integrated modelling to investigate the impact of land use and climate change on soil and water resources and to test and develop mitigation measures for the Cerrado. Copyright (C) 2014 John Wiley & Sons, Ltd.

O rio Cuiabá é um importante tributário do rio Paraguai, cuja bacia é de grande importância por agasalhar o Pantanal, a maior área úmida do planeta. A base econômica da bacia hidrográfica do rio Cuiabá é a produção agrícola e pecuária que, para manter elevada produtividade, requer grandes quantidades de insumos agrícolas como os pesticidas que, podem atingir diversos ambientes devido aos processos de dispersão que ocorrem após sua introdução no ambiente. Os sedimentos desempenham importante papel para a caracterização da poluição de rios devido a seu potencial de acumulação de poluentes. Este estudo objetivou avaliar a contaminação por pesticidas usados nas lavouras plantadas na bacia do rio Cuiabá, MT. Para tanto, amostras de sedimento de fundo foram coletadas mensalmente de agosto de 2011 a julho de 2012. Para a determinação dos pesticidas atrazina, cipermetrina, clorpirifós, endossulfam (α, β e seu metabólito endossulfam sulfato), lambda-cialotrina, malationa, metolacloro, metribuzim, parationa metílica, permetrina e trifuralina no sedimento utilizou-se método multirresíduo que consiste na extração sólido-líquido por agitação mecânica seguida de purificação por extração líquido-líquido e identificação e quantificação por cromatografia a gás acoplada a espectrometria de massas. Resíduos de pesticidas foram identificados em amostras coletadas em agosto e setembro de 2011 e janeiro, fevereiro, abril e julho de 2012, em concentrações variando de 5,7 a 79,3 µgkg-1. Embora a frequência de detecção tenha sido baixa, esses resultados indicam que há potencial de transporte de pesticidas usados na bacia do rio Cuiabá e seus tributários atingindo o Pantanal.

Os rios Cuiabá (CBA) e São Lourenço (SL) são considerados estratégicos por integrar regiões de grande relevância econômica, social e ambiental para o Brasil e o mundo. Porém, diversas atividades nas bacias destes rios podem representar fontes de metais potencialmente tóxicos e comprometer a sua qualidade ambiental. Neste trabalho foi avaliada a variabilidade espacial e temporal da concentração de metais nestas bacias e a sua relação com parâmetros de qualidade da água. Foram coletadas mensalmente, de agosto/2012 a julho/2013, 15 amostras de água superficial e 9 amostras de sedimento de fundo, nos rios CBA e SL. As concentrações de Cr, Cu, Fe, Mn, Pb e Zn nas amostras de água foram determinadas por espectrometria de emissão óptica com plasma acoplado indutivamente, e nas amostras de sedimento de leito, por espectrometria de absorção atômica com atomização em chama. Os elementos Fe, Mn, Pb e Cr apresentaram elevadas concentrações nas amostras de água e sedimento, porém apenas Pb e Cr representam potencial risco ambiental. As concentrações de Fe e Mn foram mais elevadas na parte alta do rio SL enquanto as concentrações de Cu e Pb ocorreram na área dos centros urbanos. Temporalmente, os metais estiveram associados ao regime pluviométrico. A correlação observada entre metais indica uma fonte comum. Desta maneira, a ocorrência e concentração de metais nos rios CBA e SL mostram contribuição de origem natural, reflexo do tipo de solo associado ao regime pluviométrico da região, bem como contribuição antrópica devido às atividades agropecuárias e ao lançamento de efluentes urbanos não tratados. Cuiabá (CBA) and São Lourenço (SL) rivers are considered strategic once they integrate regions, which are economically, socially and environmentally relevant for Brazil and the world. However, several activities developed in their watersheds may represent sources of metals and be a threat to the environmental quality. Thus, in this study we evaluated the spatial and temporal variability of potentially toxic metals in water and sediment and the relationship of their concentration with water quality parameters. Surface water samples were collected monthly in 15 points and bottom sediment in nine points distributed throughout both rivers from August 2012 to July 2013. Cr, Cu, Fe, Mn, Pb and Zn were determined in water by inducted coupled plasma optical emission spectrometry and in sediment by flame atomic absorption spectrometry. Fe, Mn, Pb and Cr had high concentrations in water and sediment but only Pb and Cr represent environmental risk. Fe and Mn were in higher concentrations in at the upper points of SL River and Cu and Pb in the urban area of both rivers. Temporally, the metal concentrations were associated with precipitation variation. The observed correlations amongst metal concentrations indicate common sources. Thus, the metals occurrence and concentrations in water and sediment of both rivers showed a natural contribution, as a reflex of soil type associated to the region's precipitation regimen as well as the anthropic contribution due to agricultural and cattle breeding activities, and disposal of untreated urban effluents.

The modeling of top predators’ habitats and the understanding of their environmental requirements in landscapes facing high land-use transformation pressure have long-standing importance for the development of conservation strategies. Multi-distance spatial cluster analysis and logistic regression with environmental weighting for pseudo-absence designation were applied to understand spatial patterns of jaguar occurrence in Mato Grosso state (Central Western Brazil). This location has been under intense deforestation pressure since the 1970s and is historically one of the most important jaguar habitats in the world. By using a model of five independent variables, we were able to achieve a 73.2 percent success rate of case/non-case classification and indicate not only a general loss of habitat suitability, but also an increasing interruption of potential migration corridors in the state. Our analysis on a regional scale demonstrates the importance of forest and savannah woodland for jaguar habitat maintenance in the Mato Grosso state. The jaguar species demonstrates a sensitivity to landscape fragmentation, which can be parameterized for improved model building by metrics such as edge density and patch size. Comparisons with previous studies in South America show that parameter selection for jaguar habitat modeling is highly scaledependent and that habitat suitability in partially transformed landscapes could be maintained if fragmentation is minimized. Recent land-use transformation, however, has significantly weakened the conservation status of the Pantanal-Amazon corridor.

This study examines the application of the Singular Spectrum Analysis (SSA) method to assess existing trends and oscillations in time series of mean monthly flow in non-parametric fashion. The method was applied to analyze the values of mean monthly flows recorded at the Acorizal and Cuiaba gauges located in the Cuiaba River. The results show that the SSA is able to extract the components of trend, harmonics and noise of the series. The reconstructed time series (with only the trend and harmonic components) satisfactorily reproduced the nonlinear trend of the original time series indicating that the method can be considered as a new tool to water resources management. Key-words: Time series, Mean monthly flow, Singular Spectrum Analysis (SSA), Cuiaba River

Litter production is related to canopy processes including the timing and amount of leaf development, reproduction and net primary production. However, quantifying spatial and temporal patterns in litter production is complicated in Amazonian semi-deciduous forests because of high spatial heterogeneity and seasonal variation in rainfall. Here, we use monthly measurements of litter production and Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) composites over a 6-year period to assess whether MODIS can be used to quantify litter production of tropical semi-deciduous forests. Original MODIS NDVI and EVI values were poorly related to the seasonal periodicity in litter production, but after using singular spectrum analysis (SSA) signal extraction techniques, clear relationships between litter production and the NDVI and EVI emerged. These results indicate that MODIS NDVI and EVI data are useful for detecting temporal patte...

In this paper we propose a DEM-based GIS methodology for the identification and delimitation of riparian protection areas according to stream width. In Brazil, vegetation cover in buffer zones is monitored by mid-resolution satellite imagery, so our methodological approach includes procedures to ensure geometrical accuracy for multiple spatial layer overlay. For a study area in Mato Grosso, a sequence of DEM pre-processors was used to hydrologically correct a SRTM 90 m resolution digital elevation model. Then samples of river widths were obtained by measures using high-resolution IKONOS imagery and regressed against watershed contribution areas to define protection zone buffers. We propose a procedure to attribute the DEM-based width estimates derived from topographic maps and satellite imagery to the river networks. Validation using high-resolution IKONOS imagery indicates that the proposed methodology produces RMS errors of about 20 m on average for watercourses up to 600 m wide. This is a considerable improvement in protection area delimitation compared with current practice, particularly in headwater regions and along streams with widths of up to 200 m. Accuracy assessments indicate that environmental licensing procedures should include a tolerance of between 48% (

Sprinkler irrigation, an agricultural production system that is causing increasing conflict among water resource users, is expanding quickly in the Central Western Cerrado regions of Brazil. To subsidize watershed management and concession of water rights, GIS-based spatial modelling was applied to spatially predict relative likelihood of the installation of centre sprinkler irrigation systems. Interpretation of multitemporal Landsat Thematic Mapper and Enhanced Thematic Mapper imagery was conducted to map spatial distribution of centre-pivot sprinkler systems. Multi-source data layers on environmental conditions and infrastructure were elaborated to test their predictive power in an Ecological Niche Factor Analysis, a spatial modelling technique for presence-only data. Underpinned by an exploratory analysis of spatial autocorrelation of irrigation systems, suitability predictions were found to be accurate on landscape scale and improved when the model includes underlying ecogeographical factors (EGV) suc...

Summary The relations between hydrology, geomorphology and vegetation provide the basis for understanding the ecological processes in the floodplains of rivers. In this paper, long-term (1969–2009) local flood characteristics (magnitude, duration, frequency, return period) are quantified for the floodplain of the Cuiaba River (Pantanal wetland in Brazil), using a predictive model based on artificial neural networks (ANNs) with input given by the historic river-level record. Morphological features were then described and their relation to vegetation analyzed and used to reconstruct floods. In addition to the river-level data used to train and validate a three-layer ANN, data were also used from 11 floodplain gauges across a 12 km transect lateral to the river, which were monitored during the annual floods of 2004–2007. The resulting neural network gave satisfactory estimates of water depth over the floodplain, with an absolute error of 0.09 m not exceeded in 95% of occurrences. The ANN showed that in almost all years, the level reached by the river was high enough to flood the profile completely: the exceptions were 1971 and 2001 when only 50% and 58% was flooded, to mean depths of 0.34 and 0.48 m, respectively. The highest flood was that of 1995 when the floodplain was flooded to a mean depth of 2.56 m. The median flood event (return period 2 years) produced a mean flood depth 1.80 m and lasted 119 days. Among the most important morphological features is the presence of palaeo-channels which provide hydrological connectivity between the river and the floodplain. The distribution of phytophysiognomic units is significantly influenced by local geomorphology, which determines spatial variation in the magnitude, duration, and frequency of flooding.

O ambiente físico na área de influência da hidroelétrica "Aproveitamento Múltiplo do Manso" (APM-Manso) apresenta elementos favoráveis para o desenvolvimento do ciclo silvestre da febre amarela. Neste contexto, o presente estudo visa a aplicação de técnicas de Sensoriamento Remoto, Sistema de Informação Geográfica e Regressão Logística para mapeamento da aptidão de habitats de Haemagogus janthinomys e Haemagogus leucocelaenus, os principais vetores de transmissão de Febre Amarela Silvestre. Foram realizadas 64 campanhas entomológicas entre os anos de 2000 e 2001, com capturas em oito pontos de coleta. Planos de Informação das Formações vegetais e da Terceira componente da transformação Tasseled Cap, um índice espectral da umidade da superfície terrestre foram obtidas de uma imagem multiespectral do Landsat ETM+. De um Modelo Numérico de Terreno de alta resolução foram derivados Planos de informação da Declividade, Exposição das rampas e Incidência solar. Um modelo de Regressão Logística identificou a Incidência solar, a Declividade e a Terceira componente da transformação Tasseled Cap como variáveis explanatórias significativas para a presença dos vetores. O modelo de Regressão Logística resultou em uma exatidão geral de 85,9%, um desempenho considerado satisfatório para predições espaciais da aptidão de habitats.

This study investigates the relationship between spatial patterns of water quality and land occupation in the cities of Cuiaba and Varzea Grande, Mato Grosso state, Brazil, applying Geographic Information System (GIS) techniques and Polynomial Redundancy Analysis. The results show a strong relationship between water quality and population density, urbanization rate and regionalized low water runoff. Higher treatment rates improve oxygenation levels, but do not reduce concentrations of total nitrogen, phosphorus and coliforms, indicating inefficiency of the sanitation infrastructure. The presence of more sophisticated treatment systems positively influenced catchment pollution levels. Sub-catchments which impact water quality of the Cuiaba River throughout the year typically deliver loads of mixed origin (impervious surfaces and untreated domestic wastewater). Monitoring stations downstream of the urban reach of the river show a trend of chemical and biological degradation.

Since 1999, the Manso hydropower plant has been regulating the Cuiaba River, which is one of the two main affluents of the northern Pantanal of Mato Grosso, responsible for the flooding of at least 20,000 km2 of the world's greatest floodplain. Since the initiation of regular reservoir operation in 2002, discharge at the beginning of the wet season (November–December) has been reduced by about 20%. Current power plant operation increases dry-season discharges from about 100 m3/s to 150 m3/s, resulting in water levels approximately 1 m above those recorded before regulation. Rainy season runoff higher than 400 m3/s is retained in about 6 weeks and the period of drying up is anticipated. Hydrograph analysis in conjunction with a planialtimetric field survey determined that discharge of 240 m3/s is the minimum required to initiate flooding in the Pantanal in the northern Cuiaba River floodplain, while runoff of 355 m3/s is necessary to guarantee consistent flooding of the same. Constrained by positive linear trends in precipitation and discharge, which were detected through a time series analysis of a 68-year period, two reoperation alternatives are proposed, which would not reduce mass balance of power generation, but can guarantee river overflow during the months November through May, minimizing the impact on ecological functions of the floodplain.

This study evaluates the environmental impacts caused by informal occupation in the city of Cuiaba, Mato Grosso, Brazil. In 10 selected districts, an assessment of 35 environmental indicators was conducted, evaluating secondary data as well as field survey results, air photo interpretation and geographical information system (GIS) analysis. A matrix approach was then applied to quantify the magnitude and relevance of 13 types of impacts on the following environmental components: surface water, soil, flora/fauna, air, land use and life quality. Impacts were analyzed in the spatial context of four main classes of municipal zoning. Redundancy analysis (RDA), a multivariate ordination method, was applied to evaluate the dependency of impacts from environmental and socio-economical factors. Total impact scores were the highest in areas devoted to environmental preservation according to municipal zoning, indicating a limited ability of authorities to control informal occupation processes and their impacts on the environment. Indicator analysis showed strong impacts along the stream network in areas susceptible to episodic flooding. RDA indicates that age and district organization have a significantly important impact in the sampled districts; they were found to be as important in ordination as environmental factors such as geo-technical units.

This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality. A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration.

Multitemporal data sets from the Landsat Thematic Mapper (TM) were used to evaluate their applicability for exploratory soil mapping in the floodplain of the Northern Pantanal of Mato Grosso, Brazil. Fifty-four soil profiles were classified into 21 soil units according to the FAO–UNESCO system. Information layers of vegetation types and dynamics of flooding were elaborated by applying supervised hierarchical classification rules. Geomorphologic units were mapped by visual image interpretation. Multinomial logistic regression was applied to test relations between thematic layers and soil units as well as aggregated soil clusters, developing a statistical mapping model. Northern Pantanal floodplain soils show a high variability as a function of age and granulemetry of underlying sediments, as well as soil moisture and flooding regimes. GIS layers of nine vegetation formations, three geomorphologic units and three multi-temporal moisture types were elaborated. Cross-tabulations and multinomial logistic regression models indicate significant relations between FAO–UNESCO soil units and GIS layers. As soil sampling density had been low, a final predictive model was developed for the mapping of six aggregated soil clusters, obtaining a high significance level (p

Hydrologic modeling has been one of the analytic instruments available to help water resources management. The possibility of water quality monitoring resulting from the leaching of pollutants as a result of agricultural activities, called diffuse(non-point) pollution, is the central hypothesis of this study which seeks to identify and quantify water quality changes in the Cuiaba river basin, as a function of soil cover and land use. This basin was chosen because it lies in the state of Mato Grosso which has an eminently agricultural vocation, and is located upstream from the Pantanal complex, constituting an important area for environmental studies in Brazil. The Cuiaba River basin has a drainage area of approximately 29,000 km2. RBRH – Revista Brasileira de Recursos Hidricos Volume 8 n.4 Out/Dez 2003, 115-135 135 In this context, an attempt was made to develop a distributed hydrologic model based on geoprocessing via a geographic information system (GIS). Specifically, the spatial distribution of total nitrogen and total phosphorus as pollutants in the basin is evaluated, based on the integration of data on hydrometeorology, water quality, physiography, land use and occupation and images from the Landsat 7 – ETM+ sensor in a GIS environment. The results obtained by the model, when compared to historical water quality series in the Cuiaba river basin, indicated the acceptability of the methodology proposed as an indicator of spatial variability of mean water quality.

Background In Brazil, 99% of the cases of malaria are concentrated in the Amazon region, with high level of transmission. The objectives of the study were to use geographic information systems (GIS) analysis and logistic regression as a tool to identify and analyse the relative likelihood and its socio-environmental determinants of malaria infection in the Vale do Amanhecer rural settlement, Brazil. Methods A GIS database of georeferenced malaria cases, recorded in 2005, and multiple explanatory data layers was built, based on a multispectral Landsat 5 TM image, digital map of the settlement blocks and a SRTM digital elevation model. Satellite imagery was used to map the spatial patterns of land use and cover (LUC) and to derive spectral indices of vegetation density (NDVI) and soil/vegetation humidity (VSHI). An Euclidian distance operator was applied to measure proximity of domiciles to potential mosquito breeding habitats and gold mining areas. The malaria risk model was generated by multiple logistic regression, in which environmental factors were considered as independent variables and the number of cases, binarized by a threshold value was the dependent variable. Results Out of a total of 336 cases of malaria, 133 positive slides were from inhabitants at Road 08, which corresponds to 37.60% of the notifications. The southern region of the settlement presented 276 cases and a greater number of domiciles in which more than ten cases/home were notified. From these, 102 (30.36%) cases were caused by Plasmodium falciparum and 174 (51.79%) cases by Plasmodium vivax. Malaria risk is the highest in the south of the settlement, associated with proximity to gold mining sites, intense land use, high levels of soil/vegetation humidity and low vegetation density. Conclusions Mid-resolution, remote sensing data and GIS-derived distance measures can be successfully combined with digital maps of the housing location of (non-) infected inhabitants to predict relative likelihood of disease infection through the analysis by logistic regression. Obtained findings on the relation between malaria cases and environmental factors should be applied in the future for land use planning in rural settlements in the Southern Amazon to minimize risks of disease transmission.

As in many other parts of the world, gold is produced in the surface mining region of Poconé, Mato Grosso, Brazil, using mercury. The goal of this investigation was to estimate the amount of mercury in certain tailings and to determine the area of the land that has been contaminated by the gold mining operations. Mercury concentrations from 2 to 495 ng/g (dw) were determined in the tailing materials. It was observed that only isolated sites were acting as central points of contamination. Using digital Landsat satellite data (The-matic Mapper) and aerial photos, the sites degraded by the mining were classified, and their total area was estimated to be 12.3 km(2) in the region of Poconé. It was estimated, that 4.9 km(2) were occupied by the contaminated tailings. The mean height of the pile slags was determined to be 4.5 m. From the experimentally calculated average density of the material in the tailings, 2.01 g/cm(3), the total mercury content in the piles of tailings was estimated to be 1600 ± 350 kg.