Avulsions Drive Ecosystem Services and Economic Changes in the Brazilian Pantanal Wetlands

The Pantanal wetland is a mosaic of landscapes that brings together rich biodiversity with the valuable activities of fishing, tourism and ranching. Human occupation and land use in the headwaters have intensified the rate of channel avulsions in the lower reaches of the largest megafan on the Taquari River. This study evaluates the long-term changes of landscapes in the active depositional lobe of the Taquari megafan from the perspective of local communities of pantaneiros. Maps derived from multiple decades of multispectral Landsat data have proven useful for studying land cover changes through the relationship between dry (terrestrial vegetation and soil/dry pastures) and humid landscapes (open waters, aquatic macrophytes and wet soils), as well as through Sankey diagrams and spatiotemporal mapping with Boolean operations according to the rate of dryland recovery. We found that dryland recovery associated with an older and smaller avulsion (known as Zé da Costa) is analogous to that of a most recent and much larger avulsion (known as Caronal), which is still ongoing and has greater importance due to the scale of the impacts. Land value and fish capture depreciate as the partial Caronal avulsion still evolves, increasing the likelihood of environmental conflicts. While pantaneiros no longer profit from ecosystem services of provision (e.g., livestock or fishing), dryland recovery may deliver quantifiable ecosystem services of regulation. The strengthening of partnerships among stakeholders and the implementation of environmental compensation mechanisms are central for the best management of the Pantanal\u27s megafans that ensure quality of life for all pantaneiros

METHODOLOGY FOR ANALYSIS OF DISTRIBUTION AND CLASSIFICATION OF THE INTENSITY OF DEQUADA FISH KILL EVENTS IN THE PANTANAL WETLAND

Extensive fish mortality occurs occasionally in the Pantanal wetland and the phenomenon is called dequada by local inhabitants. The phenomenon originates by deterioration water quality in rivers and lakes, and the depletion of dissolved oxygen (DO) is the major indicator. Researches have shown that dequada occurs when DO reaches values lower than 3 mg/L. In addition, the duration of these low DO values determines the intensity of fish mortality. This paper presents a proposed classification of dequada event, using water quality data for Pantanal rivers surveyed by National Agency of Water (ANA). The proposed method has qualitative and quantitative bases and utilizes mean DO value and duration of these values, based on historical series of DO measurements. The results are compared to other studies of the dequada phenomenon, showing that the method is efficient to determine locales with higher probability of dequada. The Paraguay River has displayed highest dequada intensity. The rivers with narrower floodplains, such as Piquiri River, do not have dequada or the intensity is lower. The phenomenon is shown to be linked to basin hydrological condition

SPATIOTEMPORAL EVOLUTION OF THE MARGINS OF LAKE UBERABA, PANTANAL FLOODPLAIN (BRAZIL)

Aquatic macrophytes are important components of wetland ecosystems, and studying them contributes to a better understanding of ecological succession in the Pantanal. The function and history of floating macrophytes on the shores of Lake Uberaba, located on the Paraguay River floodplain, were examined. A multitemporal analysis of Landsat satellite images in the years 1984-2015 was conducted. For the analysis, a land cover map was generated with three classes: water, aquatic macrophytes, and surroundings (undefined vegetation). The results revealed ~21.4% decrease in open water area of the lake over a period of 26 years (-4.7 km2/yr.). The expansion of vegetation helps explain the loss of open water and the recent shrinkage of Lake Uberaba. Macrophyte surface area along the lake margins grew by 1.4 km2/yr. Through ecological succession, the growth and decay of aquatic plants (r-strategists) along the lake shore likely provided the soil substrate needed for colonization by terrestrial plant assemblages (k-strategists). This hypothesis that we propose to describe the evolution of dynamic geomorphological processes in Lake Uberaba should be tested in other areas to verify its applicability to similar system

Methane emission of Amazonian hydroelectric reservoirs from Powerlaw relations.

Este trabalho tem por objetivo avaliar a emissão de metano em dois reservatórios amazônicos, Tucuruí e Samuel. A análise leva em consideração flutuações da área/cota e medidas isotópicas e de fluxos de d13CH4 obtidas em campo, as quais são influenciadas por diversos fatores simultaneamente, como ventos, pressão atmosférica, oxidação na coluna d´água e outros. A composição isotópica do metano em bolhas do sedimento indica que a principal via metanogênica é a redução de CO2. Os resultados também mostram que as emissões em reservatórios rasos são bem mais elevadas que nos mais profundos. Usando conceitos e técnicas da teoria fractal, baseada fundamentalmente em leis de potência, um modelo entre nível de água, área do reservatório e fluxo de metano permitiu estimar a emissão do reservatório de Tucuruí, num horizonte de 100 anos de vida útil, em 2,5 ± 2,7 x 10^6 toneladas de CH4. As emissões locais são amplificadas com a diminuição da cota, porém a emissão total do reservatório diminui, em função da contração da área do reservatório. Num cenário mais otimista, as emissões de Tucuruí em CO2 equivalentes devem ser 0,13 ± 0,14 x 10^6 toneladas de C/ano.The purpose of this work is evaluating methane emissions from two Amazonian reservoirs, Tucuruí and Samuel. The analysis considers fluctuations of the reservoir area-height and isotopic measurements and fluxes of d13CH4 acquired in the field, which are influenced by many factors simultaneously, such as winds, atmospheric pressure, oxidation in the water column, and others. Isotopic composition of methane in bubbles indicates that CO2 reduction is a major pathway for methane production in the sediments. The results also show that fluxes are higher in shallow reservoirs than in deeper ones. Using concepts and techniques of fractal theory, fundamentally based on power law functions, and considering a time horizon of 100 years, a model between water level, flux and reservoir area of Tucuruí allowed to estimate methane emission from Tucuruí at about 2,5 ± 2,7 x 10^6 tons of CH4. When water levels drop local methane emissions are enhanced, although, total reservoir emission decreases, due to the shrinking of the reservoir area. Over an optimistic scenario, the emissions of Tucuruí reservoir in CO2 equivalents would be around 0,13 ± 0,14 x 10^6 tons C/year

Da quantidade à qualidade

A temida explosão populacional já não se encontra no papel principal do palco das discussões ambientais no planeta e no Brasil. A tendência do aumento da população mundial é de estabilização, ainda na primeira metade deste século. O desrespeito às políticas públicas de desenvolvimento e a falta de qualidade de vida da maioria das pessoas são muito mais preocupantes hoje do que o ritmo de crescimento da população mundial. Particularmente quando se estima que dois terços da população no mundo e..

Biofuel production from water hyacinth in the Pantanal wetland

The Pantanal is a major wetland in the inner South America, with the potential for production of large quantities of biomass of aquatic floating species, especially water hyacinth (Eicchornia crassipes and E. azurea), during the aquatic phase of the flood pulse characteristic for this ecosystem. Such biomass could be wisely managed for the production of biofuels. This should be based on the concepts of renewability and ecosystem surplus, and could help in neutralizing of regional and global industrial carbon impacts and to induce socioeconomic development. The aquatic biomass exploitation would require low fossil energy and materials inputs, leaving a positive energy balance, with minimal interference in the environment. This emerging biofuel-based economy in the Pantanal can be a good example of human adaptation to climatic changes by managing carbon export of natural wetlands. The concepts described herein could be used in other natural, restored or artificially constructed wetlands

WATER BALANCE BASED ON REMOTE SENSING DATA IN PANTANAL

Water storage in a drainage basin determines its water security. The quantity of water retained in the watershed can be measured by means of the water balance calculation. This balance can be defined by the input of water subtracted from the outputs. However, for the Pantanal, the measurements of water inlet and outlet are expensive, which makes the use of remote sensing data a high impact tool with clear socioeconomic advantages. Studies of water availability with orbital sensors are relatively scarce in the Upper Paraguay Basin (BAP). This work is an attempt to estimate the BAP water balance using rainfall and evapotranspiration remote sensing data from the Tropical Rainfall Measuring Mission (TRMM) and the MODIS Global Evapotranspiration Project (MOD16), respectively. The results indicate that BAP had an annual surplus of water between 2000 and 2014, though water parameters seem weakly correlated at annual basis. However, there may be atmospheric-climatic phenomena that maximize the correlation between the hydrological parameters and the temperature anomaly with delays of 2 to 5 years, suggesting lagged teleconnections with QBO and ENSO