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Esteves, Francisco A.; Enrich‐Prast, Alex; Biesboer, David D.

doi:10.1023/a:1017550729084

Cited by 29 publications

(5 citation statements)

References 9 publications

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“…The similarity between DNP rates in the NO 3 À þ C amendments and NO 3 À originally suggests no appreciable carbon limitation for denitrifiers, in spite of the rather low total carbon concentrations (0.08e0.63%). This is consistent with several similar studies that found that NO 3 À and not organic carbon, limited sediment denitrification (Esteves et al, 2001;Wall et al, 2005). However, in this study stepwise regression suggested a positive contribution from OxC, owing to this fraction being most available for bacterial metabolism.…”

Section: Denitrification Potential Ratessupporting

confidence: 93%

Excess N2 and denitrification in hyporheic porewaters and groundwaters of the San Joaquin River, California

et al. 2020

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The San Joaquin River (SJR) in California is purported to receive high nitrate loadings from surrounding agricultural lands through both surface and groundwater inputs. To investigate the potential removal of nitrate (NO 3 À ) from surface and ground water sources, the spatial variations in dinitrogen (N 2 ) gas concentrations and direct measurements of sediment denitrification potential (DNP), with amended NO 3 À and carbon (C) treatments, were investigated in the summer along a 95-km reach of the San Joaquin River. Excess N 2 in hyporheic porewaters ranged from <0.1 to 8.65 mg L À1 and was significantly higher in porewaters from the 1.3 m (ground water source) versus 0.3 m (mixed surface and ground water) depths.In deep groundwater wells (3e7 m), median excess N 2 concentration was 5.39 mg L À1 (range ¼ <0.1 e14.6 mg L À1 ). Excess N 2 concentrations were inversely correlated with dissolved oxygen and NO 3 À concentrations suggesting denitrification as an important process in the dominantly anaerobic sediments. Hyporheic porewater NO 3 À concentrations exceeded the detection limit of 0.01 mg L À1 in only 20% of the hyporheic porewaters, in spite of high NO 3 À concentrations measured in both surface waters (mean ¼ 2.25 mg N L À1 ) and surrounding groundwaters. Sediment DNP rates averaged 253 and 297 mg N kg À1 hr À1 for NO 3 À amended, and NO 3 À þ C amended sediments, respectively, supporting the prevalence of denitrification in hyporheic sediments. Our results indicate that the hyporheic/riparian zones act as an anoxic barrier to nitrate transport from regional groundwater and as a location to remove NO 3 À from surface waters exchanging with the hyporheic zone.

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Section: Denitrification Potential Ratessupporting

confidence: 93%

Excess N2 and denitrification in hyporheic porewaters and groundwaters of the San Joaquin River, California

et al. 2020

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“…Nitrogen and carbon cycling also received substantial attention during the monitoring project of Batata Lake. The former was mainly explored regarding nitrogen fixation (Enrich-Prast et al, 1999, 2002Enrich-Prast & Esteves, 1996, 1998, Esteves et al, 2001Nielsen et al, 2004), and the latter considering particulate organic carbon incorporation by organisms (Bozelli, 1998a, b), dissolved organic carbon (DOC) quality, origin, and photo-oxidation (Amado et al, 2003(Amado et al, , 2006Farjalla et al, 2006), and recently CH 4 production (Conrad et al, 2010;Vavilin et al, 2017).…”

Section: Major Findings and Trends Over Timementioning

confidence: 99%

“…Beyond comparing natural and impacted areas, the Batata Lake monitoring project also better understood how Amazonian floods and seasonality shape local environmental conditions and aquatic communities. For instance, floods revealed to be an essential factor controlling the lake limnological features (Panosso et al, 1995;Panosso & Kubrusly, 2000;Panosso, 2000), nitrogen and phosphorus concentrations in the water (Roland & Esteves, 1993;Esteves et al, 2001;Farjalla et al, 2002Farjalla et al, , 2006, both virus and bacteria abundance (Barros et al, 2010;Almeida et al, 2015), bacteria abundance (Anesio et al, 1997), bacterial metabolism (Amado et al, 2006), and bacterial association with detritus from O. glumaepatula (Enrich-Prast et al, 2004), zooplankton abundance and composition (Bozelli, 1994(Bozelli, , 1996Bozelli & Esteves, 1995;Carneiro et al, 2003;Bozelli et al, 2015, Sodré et al, 2015, benthic macroinvertebrates metabolism, abundance and composition (Callisto & Esteves, 1995), phytoplankton abundance, biovolume and composition (Sophia & Huszar, 1996;Huszar & Reynolds, 1997;Melo & Huszar, 2000;Melo et al, 2004), and functional diversity (Cardoso et al, 2017), seston quality (Ferrão-Filho, 2000), wildrice (O. glumaepatula) growth and abundance Enrich-Prast et al, 2006;Brum et al, 2006), and plant community composition (Barbieri et al, 2000a).…”

Section: Major Findings and Trends Over Timementioning

confidence: 99%

From virus to igapó forest: a systematic review of 35 years monitoring of an Amazonian Lake impacted by bauxite tailings (Batata Lake)

et al. 2023

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Aim Long-term ecological research often integrates many research groups and subjects in one or few sites sampled systematically along the time. In the Amazon, there is a tradition of long-term research in terrestrial habitats, but this has been less common in floodplain lakes. This study systematically reviews 35 years of research (1988-2022) in Batata Lake, a clear water flood plain lake impacted by bauxite mining tailings for ten years (1979-1989) and discuss some research opportunities and challenges for the future. Methods The review covered 99 scientific reports (78 papers and 21 book chapters) comprising a large spectrum of data from snapshot observations and experiments to enduring quarterly observational and hypothesis-testing studies. Soil, sediments, and the water column were consistently sampled in natural and impacted areas. Results Research topics were quite diverse and covered biological communities from aquatic virus to igapó flooded forests and provided an overview of ecological processes such as primary and secondary production. Ecological variables monitored along the project were constrained by a strong seasonality of the flood pulse and the effect of sampling areas (natural and impacted), which was performed by very connected research groups. Conclusions Despite the extensive information, long-term ecosystem function trends are still incomplete.

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“…There might be two causes for the significant difference of NH 4 + -N and NO 3 − -N in response to litter manipulations. First, the increase of litter reduces the air circulation to a certain extent, resulting in an oxygen-deficient environment, which is not conducive to the progress of nitrification [47], hence the accumulation effect of NH 4 + -N as a substrate of nitrification is higher than that of NO 3 − -N. Second, plants preferentially absorbed NO 3 − -N from the soil in our study area [48,49], and NO 3 − -N as an anion is easily lost in the soil through soil eluviation and denitrification [50], leading to less impact of litter manipulations on NO 3 − -N. Meanwhile, we also found that litter manipulations had a significantly higher effect on surface soil inorganic N and MBN than on deep soil for a given litter manipulation (Table 3), possibly because abundant plant roots and litters and lower soil bulk density of surface soil could enhance soil microbial activities so that more soil inorganic N and MBN accumulates in the surface soil [51].…”

Section: Impact Of Litter Manipulations On Soil N Availabilitymentioning

confidence: 99%

Short-Term Litter Manipulations have Strong Impact on Soil Nitrogen Dynamics in Larix gmelinii Forest of Northeast China

Xiao

Man

Duan

et al. 2020

Forests

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Changes in above-ground litterfall can influence below-ground biogeochemical processes in forests, which substantially impacts soil nitrogen (N) and nutrient cycling. However, how these soil processes respond to the litter manipulation is complex and poorly understood, especially in the N-limiting boreal forest. We aimed to examine how soil N dynamics respond to litter manipulations in a boreal larch forest. A litter manipulation experiment including control, litter exclusion, and litter addition was performed in the Larix gmelinii forest on the north of the Daxing’an Mountains in China. Monthly soil inorganic N, microbial biomass and the rate of net N mineralization in both 0–10 cm and 10–20 cm layers, and N2O flux were analyzed from May 2018 to October 2018. In 0–20 cm soil layer the average soil inorganic N contents, microbial biomass N (MBN) contents, the rate of net N mineralization (Rmin), and the soil N2O emission in the litter addition plot were approximately 40.58%, 54.16%, 128.57%, and 38.52% greater, respectively than those in the control. While litter exclusion reduced those indexes about 29.04%, 19.84%, 80.98%, and 31.45%, respectively. Compared with the dynamics of the 10–20 cm soil layer, the N dynamics in 0–10 cm soil were more sensitive to litter manipulation. Rmin and N2O emissions were significantly correlated with MBN in most cases. Our results highlight the short-term effects of litter manipulations on soil N dynamics, which suggests that the influence of litter on soil N process should be considered in the future defoliation management of the boreal larch forest.

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Untitled

Cited by 29 publications

References 9 publications

Excess N2 and denitrification in hyporheic porewaters and groundwaters of the San Joaquin River, California

Excess N2 and denitrification in hyporheic porewaters and groundwaters of the San Joaquin River, California

From virus to igapó forest: a systematic review of 35 years monitoring of an Amazonian Lake impacted by bauxite tailings (Batata Lake)

Short-Term Litter Manipulations have Strong Impact on Soil Nitrogen Dynamics in Larix gmelinii Forest of Northeast China

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