Microbial respiration and chemical composition of different sediment fractions in waterbodies of the upper Paraná River floodplain, Brazil

Thomaz, Sidinei Magela; Pagioro, Thomaz Aurélio

doi:10.1590/s0034-71082001000200010

Cited by 10 publications

(7 citation statements)

References 23 publications

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“…Most studies of the C cycle in rivers were conducted in pristine and disturbed watersheds in temperate regions (e.g., Yang et al 1996;Jarvie et al 1997;Amiotte-Suchet et al 1999;Aucour et al1999;Telmer and Veizer, 1999;Abril et al 2000; Wang and Veizer 2000;Helie et al 2002;Dawson et al 2001; Barth et al 2003;Finlay 2003;Raymond and Cole 2003) or in the largest and most pristine watersheds of the tropics (Devol et al 1987;Richey et al 1990;Quay et al 1992;Hamilton et al 1997;Galy and France-Lanord 1999;Thomaz et al 2001;Richey et al 2002). Much less attention has been devoted to smaller disturbed and undisturbed watersheds in the subtropics or tropical regions (Ballester et al 1999;Andrews et al 1998;Das et al 2005;Stephens and Rose, 2005;Jepsen and Winemiller 2007).…”

Section: Introductionmentioning

confidence: 99%

CO2 and O2 dynamics in human-impacted watersheds in the state of São Paulo, Brazil

Salomão¹,

Cole

Clemente³

et al. 2008

Biogeochemistry

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We studied the spatial and temporal variation in O 2 and dissolved inorganic carbon (DIC) forms concentrations in ten subtropical watersheds located in the state of São Paulo, Brazil, with different degrees of impact by urbanization and landuse changes. Additionally, we used stable carbon isotopic composition of DIC to explain observed patterns. We found that land-cover changes and watershed geology are the main drivers of DIC distribution. Land-cover/use changes influence the riverine DIC in two ways: by replacing the original Cerrado 3 (C3)-type forest vegetation by C4-type vegetation composed of grasses (pasture), and by sugarcane. Most domestic sewage is dumped untreated into rivers in the state of São Paulo. Consequently, in the most densely populated watersheds, sewage is an important source of labile carbon and consequently of DIC to rivers. In terms of geology, although silicate weathering that produces kaolinite is the main type of weathering in the watersheds, the weathering of carbonate cements present in the geological formations of the western portion of the state of São Paulo are also an important source of DIC to rivers.

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Section: Introductionmentioning

confidence: 99%

CO2 and O2 dynamics in human-impacted watersheds in the state of São Paulo, Brazil

Salomão¹,

Cole

Clemente³

et al. 2008

Biogeochemistry

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“…Interestingly, Santmire and Leff (2006) found no difference in the bacterial community composition among different sediment fractions indicating that in their case, functioning rather than structure underlies these differences. Also, Thomaz et al (2001) found no correlation between particle size and microbial respiration in waterbodies of the upper Paraná River floodplain but did recognize the phosphorus contents as important variable. In contrast to our study, their study compared fine sediments, with four sediment classes of sizes below 0.070 mm.…”

Section: Discussionmentioning

confidence: 76%

Testing the influence of sediment granulometry on heterotrophic respiration with a new laboratory flow-through system

et al. 2016

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Purpose Increased sedimentation due to land use intensification is increasingly affecting carbon processing in streams and rivers around the globe. This study describes the design of a laboratory-scale flow-through incubation system as a tool for the rapid estimation of sediment respiration. The measurements were compared with those obtained using an in situ closed chamber respiration method. The influence of sediment size on respiration rates was also investigated. Materials and methods Measurements were conducted on a pre-alpine gravel-bed river sediment separated into the following grain size fractions: > 60 mm (14.3%), 60-5 mm (60.2%), 5-2 mm (13.7%), 2-0.063 mm (11.1%) and <0.063 mm (0.6%). Concurrently, in situ and laboratory measurements were carried out on a naturally heterogeneous sediment. In situ respiration was determined in closed chambers as O 2 consumption over time, while in the laboratory, respiration was determined using flow-through respiration chambers. Oxygen concentrations were measured using a fibre-optic oxygen meter positioned at the inflow and outflow from the chamber. Results and discussion The mean respiration rates within naturally mixed riverbed sediments were 1.27 ± 0.3 mg O 2 dm −3 h −1 (n = 4) and 0.77 ± 0.1 mg O 2 dm −3 h −1 (n = 3) for the flow-through chamber system and closed chamber system, respectively. Respiration rates were statistically significantly higher in the flow-through chamber system (t test, p < 0.05), indicating that closed chamber measurements underestimated the oxygen consumption within riverbed sediments. Sediment grain size was found to significantly affect respiration rates in both systems (ANOVA, p < 0.001) with the fine sediment fraction (particle size <0.063 mm) having the highest respiration rate (r flow-through = 51 ± 23 mg O 2 dm −3 h −1 ). The smallest fractions (2-0.063 and <0.063 mm), which represent approximately 12% of total sediment volume, contributed 60% of total respiration. Conclusions The study demonstrated that flow-through respiration chambers more accurately estimate the respiration rate within riverbed sediments than in situ closed chambers, since the former experiment imitates the natural conditions where continuous interstitial flow occurs in the sediments. We also demonstrated that fine sediments (<5 mm) substantially contribute to heterotrophic respiration in the studied gravel-bed river.

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“…We observed a significant temporal influence of SIM on the abundance of exogenous testate amoebae. Thomaz, Pereira, & Pagioro, suggested that the direct or indirect influence of suspended inorganic material on the distribution of organisms may be more explicit in floodplain environments, where its availability is controlled by the hydrological regime.…”

Section: Discussionmentioning

confidence: 99%

Testate amoebae as indicators for suspended inorganic material in floodplains influenced by dam

Schwind

Arrieira

Mantovano

et al. 2018

Internat Rev Hydrobiol

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The construction of reservoirs impacts upon freshwater ecosystems, since it changes the hydrodynamics of the entire system upstream and downstream of the dam due to flow control and changes in environmental conditions. We analyzed the temporal variation in the abundance of exogenous testate amoebae related to the suspended inorganic material in Neotropical floodplain lakes, downstream of a series of dams. Sampling was carried out between 2000 and 2012 in six lakes in the upper Paraná River floodplain. The temporal variation in the abundance of the testate amoeba community was analyzed using the Threshold Indicator Taxa Analysis. Cucurbitella crateriformis, Protocucurbitella coroniformes, and C dentata f. quinquilobata had reduced population growth in higher concentrations of suspended inorganic material. On the other hand, Difflugia lobostoma, Centropyxis ecornis, and Difflugia pseudogramen populations increased under these conditions. These results showed that an increased flow of water could favor the growth of some populations due to the greater exchange of material between the lakes and the floodplain. The positive or negative responses could show better adaptation of the testate amoeba species to the planktonic environment. Furthermore, these results also highlighted the bioindicator role of these protozoa in aquatic ecosystems.

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Microbial respiration and chemical composition of different sediment fractions in waterbodies of the upper Paraná River floodplain, Brazil

Cited by 10 publications

References 23 publications

CO2 and O2 dynamics in human-impacted watersheds in the state of São Paulo, Brazil

CO2 and O2 dynamics in human-impacted watersheds in the state of São Paulo, Brazil

Testing the influence of sediment granulometry on heterotrophic respiration with a new laboratory flow-through system

Testate amoebae as indicators for suspended inorganic material in floodplains influenced by dam

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