ng

Filireumi

do R

Soaixa

Bacterial respiratory activityBiochemical compositionEsterase enzymes

o q

creating and establishing eutrophication indicative rates and records compatible with tropical coastal

te and

of benthic organisms may be fundamental in accounting for thequantity and quality of the bulk organic matter of sediments(Emerson et al., 1985; Cowie and Hedges, 1992; Danovaro et al.,1999; Fiordelmondo and Pusceddu, 2004). Marine sediments arealso intensively colonized by microorganisms (bacteria, cyanobac-

microbes may use alternative electron acceptors (nitrate, manga-nese, iron, sulfate, and carbon dioxide) for the oxidation of organicmaterial. Combined with their logarithmic growth and shortgeneration times microbes possess a high metabolic potential(Demaison and Moore, 1980; Relexans et al., 1992; Meyer-Reiland Kster, 2000). Finally, although a part of the settled organicmatter may return to the water column, a fraction will remain asa sedimentary record (Tselepides et al., 2000).

The bacteria involved in anaerobic mineralization in sedimentsare generally much less versatile than the aerobic ones (Sepers,1981) as to the amount of organic carbon and the energy sources

* Corresponding author. Tel.: +55 (21) 2629 2312; fax: +55 (21) 2629 2292.E-mail addresses: lffontana@hotmail.com (L.F. Fontana), graciano@geologia.

ufrj.br (J.G. Mendona Filho), annibal@vm.uff.br (A.D. Pereira Netto), esabadini@gmail.com (E. Sabadini-Santos), alberto@igeo.uff.br (A.G. de Figueiredo), mirian@

Marine Pollution Bulletin 60 (2010) 16741681

Contents lists availab

Marine Pollut

lsevm.uff.br (M.A.C. Crapez).a given water column. Initially this organic matter consists of allthe major classes of naturally occurring organic compounds suchas sugars, amino acids, pigments, phenolic substances, lipids, poly-peptides, polysaccharides, and other constituents of living organ-isms. During the sedimentation process, only a small portion ofthe initial organic matter reaches the bottom sediments (Premuzicet al., 1982).

After sedimentation, organic particles are equally subjected to acontinuous degradation and mixing process, while deposition ofother materials continues at the same time (Colombo et al.,1996). Thus, environmental and biological factors such as thedepth of the water column, resuspension events, the concentrationof dissolved oxygen, primary production or the metabolic activity

cellular polymeric substances (EPS) secreted by the cells. Throughtheir organization in biolms, organisms create their own micro-habitats with pronounced gradients of biological and chemicalparameters. Along these gradients they can use substrates andenergy effectively (Meyer-Reil, 1994). Microorganisms are presentin sediments in high numbers (about 1010 cells g1 d.w.). Their bio-mass is greater than the biomass of all other benthic organisms.The cell surface of microbes by far exceeds that of all other organ-isms. Microbes possess a high surface-to-volume ratio, indicatingtheir high metabolic activity rates. Dissolved inorganic and organicsubstrates can be metabolized with high substrate afnity andspecicity. Particulate organic matter can be decomposed in closecontact with the substrate by hydrolytic enzymes. Besides oxygen,1. Introduction

Organic matter occurs in particula0025-326X/$ - see front matter 2010 Elsevier Ltd.doi:10.1016/j.marpolbul.2010.06.049systems. The biochemical representative relationships in the cores were equivalent to those from studieson coastal marine environments made in the Northern Hemisphere. The esterase enzymes in the sedi-ment proved efcient in the mineralization of biopolymers, even with preferentially anaerobic metabolicphysiology. Despite the lack of incipient geomicrobiological studies, the results highlighted the possibleapplication of microbiology to a better understanding of geological processes.

2010 Elsevier Ltd. All rights reserved.

dissolved forms within

teria, fungi, algae; size 150 lm). Most are organized in biolms,complex associations of microbes immobilized on surfaces andembedded in an extracellular organic matrix, consisting of extra-SedimentGeomicrobiology

terial respiratory activity in four cores collected in Suru Mangrove, Guanabara Bay RJ. Biopolymer con-centration was 1000 times lower than previously reported in the literature, indicating the need forGeomicrobiology of cores from Suru Ma

Luiz Francisco Fontana a,*, Joo Graciano MendonaElisamara Sabadini-Santos d, Alberto Garcia de Figuea Programa de Ps-Graduao em Geologia e Geofsica Marinha, Universidade Federal Fls/n Campus da Praia Vermelha to Gragoat, Niteri, RJ, CEP 24210-340, Brazilb Programa de Ps-Graduao em Geologia, Instituto de Geologia, Universidade FederalCidade Universitria, Ilha do Fundo, Rio de Janeiro, RJ, CEP 21949-900, BrazilcPrograma de Ps-Graduao em Qumica, Universidade Federal Fluminense, Outeiro ded Programa de Ps-Graduao em Biologia Marinha, Universidade Federal Fluminense, C

a r t i c l e i n f o

Keywords:

a b s t r a c t

The aim of this work was t

journal homepage: www.eAll rights reserved.rove Guanabara Bay Brazil

ho b, Annibal Duarte Pereira Netto c,do Jr. a, Mirian Arajo Carlos Crapez d

nense, Av. General Milton de Tavares de Souza,

io de Janeiro, Av. Athos da Silveira, 274, Bloco J, sala JI20,

Joo Batista, s/n, Valonguinho, Centro Niteri, RJ, CEP 24020-141, BrazilPostal: 100.644, Niteri, RJ, CEP 24001-970, Brazil

uantify the biopolymers associated to esterase enzymes and identify bac-

le at ScienceDirect

ion Bulletin

vier .com/locate /marpolbul

that can be used. An exception may be some denitrifying bacteriathat are active in sediment surfaces and whose anaerobic metabo-lism does not greatly differ from their metabolism under aerobicconditions. However, for apparently stringent reasons, such quan-titatively important substrates as glucose cannot be oxidized tocompletion by microbes that can carry out anaerobic respirationin which sulfate or carbon dioxide act as electron acceptors. In con-trast to aerobic environments, mineralization in sediments is theresult of a sequence of processes whereby products of one meta-bolic group of organisms form the substrate for others. The com-munities thus formed therefore consist of microbes that arehighly dependent on each others activities. For this reason, theparticipants in anaerobic mineralization processes are of particularinterest to the study of microbial interactions.

A community similar to the one found in sediments occurs inthe anaerobic environment created by man for the degradation oforganic matter in sewage. The 2000 oil spill was one of the mostsevere ever recorded in Guanabara Bay, hitting several ecosystemsin the region. It was the second accident with the same pipeline,which had already leaked in 1997, due to the rupture of a Duquede Caxias Renery (REDUC) oil pipeline. According to Petrobrasestimates, a total of about 1300 m3 of crude leaked, of which 25%(325 m3) evaporated, 40% (520 m3) were recovered and the rest(455 m3) was retained in mangroves and rocky shores (Mitchel,

their buttress roots. The mangrove is under strong anthropic pres-sure, since due to the tidal regime it is possible to nd, all around it,garbage that invades it by the fringe. The predatory practice ofcatching crabs with rafa sacks next to the burrows, and the indis-criminate tree logging, landlling, draining and deforesting alterhydrological conditions and, consequently, mangrove functioning,thus hampering management and conservation and constitutinga great impact over the Guapimirim APA mangroves (Soareset al., 2006).

The aim of this work was to characterize sediment samples col-lected in Suru Mangrove as to levels of organic matter and bio-polymers, and granulometry, and verify their relationship tobiomass, metabolism and bacterial enzymatic activity.

2. Materials and methods

The Suru Mangrove (7.489.800 S, 694.280 W, Zona 23 S) islocated in Mag Municipality spanning approximately 80,000100,000 m2. Because it is located to the north of the GuapimirimEnvironmental Protection Area (APA), it shares features with thezone termed Norte-APA de Guapimirim, Guanabara Bay, Rio deJaneiro, Brazil (Fig. 1).

This mangrove is bound by Morro da Solina to the west and by

L.F. Fontana et al. /Marine Pollution Bulletin 60 (2010) 16741681 16752000). The Suru Mangrove area may have been impacted by partof the oil spilled in that incident. Its importance increases by thepresence of the Suru River and the Suru-Mirim Channel, both act-ing in some parts as boundaries to Guapimirim APA, and by the factthat they ow into Guanabara Bay (Soares et al., 2006). Water owthrough the mangrove is reduced by mangrove plants, characteriz-ing complex current patterns, including jets, eddies and stagnantzones. The ow of suspended sediment shows that most of itreturns and settles in the mangrove itself, and is not reexported(Furukawa et al., 1997). Suru Mangroves predominant plant spe-cies along most of the Suru Rivers 3600 m (from Suru to themouth) is the white mangrove (Laguncularia racemosa). There arealso, interspersed, a few clusters of black mangrove (Avicenniaschaueriana), with their pneumatophores. Closer to the mouthsome clusters of red mangrove (Rhizophora mangle) appear, withFig. 1. Localization of Suru Mangrove and appthe RJ-116 highway to the north. Its importance increases by thepresence of the Suru River and the Suru-Mirim Channel, both act-ing in some parts as boundaries to Guapimirim APA, and by the factthat they ow into Guanabara Bay (Soares et al., 2006). Like mostrivers in the region, they are constantly ooded and have predom-inantly at topography, close to sea level, which generates thedevelopment of mangroves and the presence of chernies at theedges and fringe (Fontana et al., submitted for publication).

Four sediment samples were collected in triplicate, using PVCsoil cores (4.5 30.0 cm) (Fig. 1) during 2008. To facilitate thetransportation and analyses of the cores, they were cut in 5-cmsections. Each section was divided into the following intervals:03, 510, 1015, 1520, 2025 and 2530 cm. These sampleswere stored in sealed polythene bags, conditioned in ice and takento the laboratory, where they were processed and analyzed.roximate localization of sampling points.

tionThe particle size distributions of sediments were evaluated intriplicates using 4 g of sediment samples. The distributions weredetermined with a Malvern laser sediment meter, model Master-sizer 2000, with an analysis capacity of particle sizes ranging from0.02 to 2000 lm and classied according to the textural classica-tion proposed by Flemming (2000).

Total organic matter was estimated in triplicates by the calcina-tion method. Around 50 g of wet samples were dried to a constantweight and calcinated. Organic matter (OM) was determined as thedifference between sediment dry weight (60 C, 24 h) and weightof the residue after combustion (450 C, 4 h) (Byers et al., 1978;Baptista Neto et al., 2000; Crapez et al., 2003).

Concentrations of total biopolymers (carbohydrate, lipids andproteins) were determinated in triplicates, using one gram of sed-iment samples. All determinations were done by spectrophotomet-ric methods. Carbohydrates (CHO) were quantied using the sameprinciple as Dubois et al. (1956), according to the modied methodof Gerchacov and Hatcher (1972) for sediment analysis, using glu-cose as a standard. Lipids (LIP) were extracted with chloroform andmethanol and analyzed according to Marsh and Wenstein (1966);tripalmitine was used as the standard. Proteins (PTN) were deter-mined according to the method proposed by Hartree (1972) andmodied by Rice (1982), to compensate for phenol interference.Bovine albumin, fraction V (Sigma), was used as the standard.

The sum of protein, carbohydrate and lipid carbon equivalentswas referred to as biopolymeric carbon (BPC) (Fabiano et al.,1995) and the bioavailable organic carbon (%) was determinedaccording to the equation: [(total biopolymeric carbon 100)/totalbiopolymers)]. The unavailable organic carbon (%) was determinedaccording to the equation: (100 total biopolymeric carbon).

Esterase enzyme activity (EST) was analyzed according to Stub-bereld and Shaw (1990). It is based on uorogenic compounds,which are enzymatically transformed into uorescent products thatcan be quantied by spectrophotometric assay. These enzymes acton biopolymers and transform them into low-molecular-weightorganic carbon. Triplicates of 1 g of each sediment were analyzed.The results were expressed in lg uorescein/h g of sediment.

Electron transport systemactivity (ETSA)wasmeasured accordingto Trevors (1984) andHouri-Davignon and Relexans (1989), based ondehydrogenase enzyme activities. These enzymes provide equiva-lents for ATP synthesis (third phosphate adenosine) in the electrontransport systems. Triplicates of 1 g of each sediment were used.Results from this assay were expressed in lL O2/h g of sediment.

Metabolic bacterial activity such as aerobic, facultative anaero-bic, denitrication and sulfate reduction was measured usingmethodology described by Alef and Nannipieri (1995), using tripli-cates of 1 g of each sediment.

Bacterial carbon (BC) was enumerated by epiuorescentmicroscopy (Axiosp 1, Zeiss, triple lter Texas Red DAPI uores-cein isothiocyanate, 1000magnication) and using uorochromeuorescein diacetate and UV-radiation (Kepner and Pratt, 1994).Carbon biomass (mg C/g sediment) data were obtained using themethod described by Carlucci et al. (1986).

The statistical analyses considered sediment core samples andthe evaluated parameters. Wards Method with City-block(Manhattan) distance was used. It is distinct from all other meth-ods because it uses an analysis of variance approach to evaluatethe distances between clusters. In short, this method attempts tominimize the Sum of Squares (SS) of any two (hypothetical) clus-ters that can be formed at each step. This distance is simply theaverage difference across dimensions. In most cases, this distancemeasurement yields results similar to the simple Euclidean dis-tance. However, note that in this measurement the effect of single

1676 L.F. Fontana et al. /Marine Pollularge differences (outliers) is dampened (since they are notsquared). The package Statistica was used with this purpose.3. Results and discussion

Granulometric fractions in the cores varied from sand to clay.Sedimentary layers were comprised of 2589% silt, 420% clayand 074% sand. Following Flemmings (2000) classication, coresamples were classied into six main groups: silt (E-I sample 7),slightly clayey silt (E-II samples 11, 12, 17, 23 and 24), extremelysilty slightly sandy mud (D-I samples 8 and 9), extremely silty san-dy mud (CI samples 14, 15, 21 and 22), very silty sandy mud (CII samples 1, 2, 4, 6 and 18) and very silty sand (B-I samples 3, 5, 10,16, 19, 20 and 22) (Fig. 2).

Organic matter in the sedimentary layers varied from 1.3% to4%, the largest values being determined in the top layers, with anaverage of 3%. The deepest layers presented an average of 1.5%(Fig. 2). Our values agree with those previously determined byDa Silva et al. (2008), Baptista Neto et al. (2006) and Catanzaroet al. (2004), who analyzed sediment samples of Guanabara Bay.The highest level of organic matter was found in the areas closeto the Guapimirin APA at 8.4%. Comparatively higher levels oforganic matter, ranging from 0.97% to 15.4%, were found inUbatuba Bay in 38 supercial sediment samples (Burone et al.,2003). In a study on Italys Apulian coast, DellAnno et al. (2002)found total organic matter contents between 1.8% and 5.4%.

Biopolymers were distributed over all sedimentary layers andvaried widely. CHO showed its largest and lowest concentrationsin, respectively, the 03 cm layer of core 2 (311.3 lg/g) and inthe 1015 cm layer of core 2 (110.6 lg/g) (Fig. 2). PTN also showedthe largest and lowest concentrations in core 2 (403.1 and 77.6 lg/g) respectively (Fig. 2). LIP levels were lower than CHO and PTN.The largest concentration was found in core 1 (99.1 lg/g) whilethe lowest one was obtained in core 2 (11.6 lg/g) (Fig. 2).

The highest values for biopolymeric organic carbon wereobserved in all cores (Fig. 2). The largest concentration was deter-mined in core 2 at 275 lg/g and the smallest in core 3 at 130.9 lg/g. Bioavailable carbon obtained uniform distribution in the 4 cores,ranging from 47% to 49% (Fig. 2).

Our values resembled those found by Da Silva et al. (2008), whodetermined protein (22111 lg g), carbohydrate (2191483 lg/g)and lipid (641711 lg/g) distribution in 30 supercial samplesfrom Guanabara Bay, with biopolymeric carbon values rangingfrom 191 to 1684 lg/g. Pusceddu et al. (1999) found 76070530 lg/g of carbohydrates, 216012,100 lg/g of proteins and2604470 lg/g of lipids in the sediments from the western Medi-terranean (Italy). DellAnno et al. (2002) found 4600 lg/g of carbo-hydrates, 3702100 lg/g of proteins and >1000 lg/g of lipids onthe Apulian Coast of Italy. However, DellAnno et al. (2002) founda variation of 900 to 6900 lg C/g in the sediments. These valueswere not similar to the results found in this study.

Pusceddu et al. (1999) and DellAnno et al. (2002) found the fol-lowing relationship: carbohydrates > protein > lipids. In regard tothe functional role of proteins, DellAnno et al. (2002) related it tothe high levels of primary production, while Pusceddu et al.(1999) dened it as a limiting factor for benthic organisms. The low-er hydrodynamics in this area (Kjerfve et al., 1997; Amador, 1980)probably explained the higher lipid levels associated to ne sedi-ments. DellAnno et al. (2002) associated the increase in lipid levelsto the increase in sediment depth, which was not veried in our re-sults. In Guanabara Bay lipid were the most abundant polymers,after carbohydrates (Da Silva et al., 2008), due to the associationwith hydrophobic organic micropollutants (HOMs including hal-ogenated hydrocarbons, plasticizers, fused-ring hydrocarbons andpesticides) (Turner and Millward, 2002). A raw sewage input inthe order of 20 m3/s (derived from a population of about 7.3 106

Bulletin 60 (2010) 16741681inhabitants) is a major cause of environmental concern (Feema,1990). The uneven distribution of nonpoint sources of sewage has

tionL.F. Fontana et al. /Marine Polluresulted in pronounced spatial gradients of contamination in baywater and sediments (Kjerfve et al., 1997; Valentin et al., 1999; Cra-pez et al., 2000; Baptista Neto et al., 2005; Brito et al., 2006). (Carre-ira and Wagener, 2003; Carreira et al., 2004), and Pinturier-Geisset al. (2002) highlighted that preservation of lipids in the sedimentswas linked to the prevailing anoxic condition.

Although several authors have identied the eutrophication pro-cess in various environments using biopolymeric ratios, this toolcannot be applied in the present study due to the heterogeneousresults, probably linked to the greater speed of physico-chemicalreactions in tropical environments (Fontana et al., submitted forpublication).

The available biopolymeric carbon average was approximately50%. It is a function of organic matter that initially escapes remin-eralization due to rapid sinking, encapsulation or surface associa-tion and aggregation that may be enzymatically inaccessible indepths for the bacterial communities (Lee et al., 2004). This occurswith the adsorption of organic compounds onto a mineral matrix,

Fig. 2. Variation of grain sizes, organic matter, carbohydrates,Bulletin 60 (2010) 16741681 1677and it has been suggested that organic matter in association withmineral material beyond that equivalent to a mono-layer coatingmight be due to its isolation from oxygen (Crapez, 2008, 2009;Lee et al., 2004). According to Henrichs (1992), the labile portionof organic matter consists of simple or combined (e.g., biopoly-mers) compounds, which include carbohydrates, lipids and pro-teins that are rapidly mineralized. Some labile compounds maybecome recalcitrant to degradation as a result of complex interac-tions between the sedimentary matrix and/or refractory organicmolecules (Keil et al., 1994).

Sedimentary organic matter is dominated by carbohydrates(46%), followed by proteins (42%) and lipids (12%), indicating greatconcentration of bioavailable substances to the microbiota. Com-plexation of this bioavailable organic matter with polluting organicsubstances present in the area (Fontana et al., submitted for publi-cation) makes it recalcitrant.

The large concentrations of high nutritional value organic mat-ter in the sediments suggest that the latter behave as detritic traps.

proteins, lipids and biopolymeric carbon in core samples.

Considering that the main sources of organic matter in mangrovesare vascular plants, it is not directly bioavailable to benthic con-sumers, and tends to accumulate.

Bacterial carbon (BC) did not have similarities in the vertical dis-tribution in the cores. The largest concentration was 1.7 lgC/cm3 incore 1, and the smallest 0.4 lgC/cm3 in cores 2 and 3 (Table 1).

Due to the anoxic sedimentary environment, hydrolysis oforganic matter biopolymers is carried out by anaerobic bacteria,with high esterase enzyme activity and less electron transport sys-tem activity. Anaerobic processes such as fermentation, denitrica-tion and sulfate reduction are energetically less efcient, but arethe ones responsible for the biogeochemical cycles in GuanabaraBay sediments (Da Silva et al., 2008). This hypothesis is borneout by the low activity of the electron transport system, responsi-ble for the energy synthesis process and, concomitantly, of bio-mass. Other studies corroborate this statement (Relexans et al.,1992; Fenchel et al., 1988; Edwards et al., 2005).

Electron transport system activity (ETSA) yielded lower concen-trations than esterase activity (EST). ETSA presented its largestconcentration in cores 2 and 3 at 0.5 lg O2/h g. In core 2 no activitywas detected in the 03 and 510 cm layers (Table 1). The lowestdetected concentration was 0.4 lg O2/h g in core 1. Between layersin each core ETSA displayed considerable variation, possibly result-ing from water ow, quality of organic matter (proteins, lipids andcarbohydrates) and grain characteristics.

EST presented its highest concentration in core 1 at 1.2 lg of

3.63 lg uorescein/h g and 3.38 lL O2/h g, respectively (BaptistaNeto et al., 2004). Da Silva et al. (2008), sampling 30 points ofsupercial sediment along Guanabara Bay, found an average valueof 3.20 lg of uorescein/h g for esterase activity and low electronsystem transport activity concentrations at only 15 points.

Bacterial respiratory activity (Table 1) indicated an overlappingof aerobic and facultative anaerobic results in all cores and pre-sented aerobic process in few layers. Sulfate-reduction and denitri-cation, anaerobic processes, were present in all supercial layers.These results indicate that the metabolism responsible for theorganic matter and nutrient cycle are affected by an anaerobic bac-terial food web that can use electron acceptors like nitrogen, iron,manganese and sulfur which may be derived from continental andcoastal erosion (Turner and Millward, 2002). After polymer cleav-ages, monomers and oligomers are carried into the cell, becomingavailable for the oxide reduction reactions that culminate in theproduction of energy. However, the facultative anaerobic, denitri-cation and sulfate reduction processes produce, respectively, 50,100 and 170 kJ/mol, as opposed to the aerobic process, which pro-duces 500 kJ/mol (Edwards et al., 2005).

SRB are predicted to facilitate precipitation of calcium carbon-ate ions in solution. These bacteria impact the pH, because forevery sulfate and two organic carbons consumed, one calcium car-bonate can potentially precipitate (Baumgartner et al., 2006). Theresults demonstrated that SRB were found in all sediments coresfrom Suru Mangrove because they utilize energy eld based elec-

tivit

1678 L.F. Fontana et al. /Marine Pollution Bulletin 60 (2010) 16741681uorescein/h g in the 03 cm layer. Its lowest concentration was0.04 lg of uorescein/h g in core 2 (Table 1).

All values were similar to those found for the environments thatcompose Guanabara Bay. Crapez et al. (2001) determined 0.54 lgof uorescein/h g for esterase activity and 0.31 lL O2/h g for elec-tron transport system activity in sandy sediments from Praia deBoa Viagem (Guanabara Bay). In another study with sedimentsfrom the same site, Crapez et al. (2003) found different patternsin enzymatic determinations performed at different seasons ofthe year. Esterase activity and electron transport system activitywere highest in samples from Niteri Harbor (Guanabara Bay), at

Table 1Bacterial carbon, heterotrophic bacteria, metabolism bacterial activity and esterase ac

Core Samples (cm) BC (lgC/cm3) MBA

A F

T1 03 0.56 V P510 0.46 V P1015 1.06 V P1520 1.64 V P2025 0.61 V P2530 1.73 A P

T2 03 1.11 P P510 0.42 V V1015 1.04 P P1520 1.59 V P2025 0.40 A P2530 0.73 A P

T3 03 0.94 V V510 1.34 V P1015 0.98 V P1520 0.51 V P2025 1.01 A P2530 0.84 V V

T4 03 1.08 P P510 0.79 P P1015 0.50 P P1520 0.87 V P2025 1.04 P P2530 0.35 V PBC, bacterial carbon; MBA, metabolism bacterial activity; A, aerobic; F, facultative anaeresterase enzymes; ETSA, enzymatic transport system activity.tron acceptors: rst oxygen, then nitrate/nitrite and nally sulfurcompounds (e.g., sulfate, sulte, thiosulfate and elemental sulfur)(Krekeler and Cypionka, 1995). An association of SRB and denitri-cation microorganisms could also explain our results. When SRBreduce nitrate/nitrite and produce ammonia nitrogen, denitrifyingbacteria can carry out anaerobic oxidation, with generation of gas-eous nitrogen (Shivaraman and Shivaraman, 2003).

The evaluation of all parameters utilizing Wards Method andManhattan Distance showed three groups. The rst group wasformed by silt and clay. The second was formed by BC, EST andthe sources of available carbon in the sediments, such as PTN,

y in core samples.

EST (lg uorescein/h/g) ETSA (lg O2/h/g)

DN SR

P P 1.24 0.16P P 1.21 0.18P P 0.55 0.31P P 0.56 0.05P P 0.38 0.05P P 0.49 0.04P P 1.03 0.00P V 0.28 0.00P V 0.15 0.06P P 0.04 0.17P P 0.34 0.50P P 0.26 0.22P P 0.26 0.13P V 0.41 0.59P P 0.39 0.19P P 0.33 0.46P P 0.42 0.18P P 0.57 0.24P P 0.73 0.48P P 0.63 0.45P P 0.53 0.57P P 0.51 0.48V P 0.47 0.20A P 0.27 0.24obic bacteria; DN, denitrication; SR, sulfate reduction; P, positive; V, variable; EST,

CHO and LIP. The last group was formed by sand, ETSA and OM(Fig. 3). The bacterial carbon, esterase enzyme activity and biopoly-mers are close to silt and clay, because the nest grains representa major microhabitat for these microorganisms. The esteraseenzyme activity was detected in the coarse sediment, suggestingthe availability of molecules with molecular weights up to600 Da (Weiss et al., 1991). Actually, the ETSA was minor due donot have molecules inside the cells to make energy.

Correlation analyses using the studied parameters showed twopositive correlations. The rst was between clay and silt, and mayhave been caused by the mineralogical composition, which hasdenite effects on the clay fraction, with consequences to the siltfraction. The second was between CHO and LIP. This correlationdoes not mean that the presence of one class of compound neces-sarily implies in the presence of the other. To state that, specicexperiments would have to be conducted. There is thus the possi-bility of connective processes, which might act in a wide, complexsystem. The negative correlations between sand and silt and sandand clay demonstrated differences in mineralogical composition,which inuence the presence of fractions. These differences arethe result of the large contribution of the sand fraction, due tothe occurrence of chernies. The negative correlation between bio-polymers demonstrates the different quality of organic mattercomposition in the same site. These differences maybe explainedthe contribution of industrial and municipal sewage in the region.The negative correlation found between clay and organic matter ofthe sediment can also be explained by the high porosity and per-meability of this kind of bottom (Table 2).

4. Conclusion

The Suru Mangrove show different composition of organic sub-stances in the surface and subsurface sediments and prevent thedecreasing of more complex compounds by bacterial communities,despite the high development of bacterial communities present insediments, responsible for processing the biogeochemical cycles.

Tide inow due to the at topography (Fontana et al., submittedfor publication) favors a greater distribution of organic compoundsover the mangrove, thus facilitating incorporation into supercialsediments and the establishment of aerobic bacteria, which partlycontribute to the diagenesis of carbon, nitrogen and the nutrientsthat result in products that maintain facultative anaerobic, denitri-fying and sulfate-reducing bacteria.

3 (C

ETSA

1.00.00.10.30.2

L.F. Fontana et al. /Marine Pollution Bulletin 60 (2010) 16741681 1679Fig. 3. Clustering of parameters using Wards Method and Manhattan Distance.

Table 2Correlations for all parameters. Marked correlations are signicant at p < .05000, N = 2

CorrelationsOM LIP PTN CHO

OM 1.00LIP 0.44 1.00PTN 0.24 0.35 1.00CHO 0.70 0.63 0.15 1.00ETSA 0.29 0.10 0.26 0.23EST 0.14 0.31 0.09 0.20BC 0.18 0.02 0.13 0.00SAND 0.39 0.00 0.14 0.36CLAY 0.59 0.28 0.26 0.41

SILT 0.31 0.07 0.23 0.32 0.3

OM, organic matter; LIP, lipid; PTN, protein; CHO, carbohydrate; ETSA, electron transpoThe important occurrence of viable anaerobic bacteria throughthe cores, observed by the high concentrations of bacterial carbonand high concentration for OM characterizes an anoxic environ-ment. In this way, diagenesis of organic matter occurs throughthe cores where an expressive biomass of anaerobic bacteria exists,and the esterase enzymes, rather than investing in highly complexorganic compounds, prefer biopolymers, which are present in highconcentrations and are less complex.

Biopolymer and biopolymeric carbon concentrations were sim-ilar to the results found in the studies previously performed inGuanabara Bay. However, biopolymeric carbon concentrationswere 1000 times smaller in the Northern Hemisphere, indicatingthe need for the establishment of new indices indicating the tro-phic levels present in tropical coastal systems.

The location of core 1 at the back of Suru Mangrove is a possi-ble tide site for deposition of particulate matter, stabilized by thetides and the surrounding rivers, on the supercial layers. Thishypothesis is based on the highest bacterial carbon and esteraseactivity results.

Being the deposition rate of Suru Mangrove approximately upto 2.2 cm/year (Ribeiro et al., 2008) this core 2 is possibly localizedin a more washed-over region and thus has less deposition of par-ticulate matter. The core 3, in contrast, while near the center ofmangrove, is reached by the ow and inux and so has its super-cial layer washed, but it is possible to nd high concentrations ofbiopolymers into the deeper layers due to migration vertical andbioturbation of the region.

Core 4, although located in the area with greater inow ofGuanabara Bay waters, and although with high washing and mix-ing of sedimentary layers, was almost equally impacted, demon-strating a possible continuous impact of the area. Thesehypotheses are based on the smallest bacterial carbon and highestelectron transport system activity results. These results demon-strated have not connection between the bacterial anaerobic car-bon and electron transport system activity.

asewise deletion of missing data).

SAND CLAY SILTEST BC

05 1.004 0.30 1.006 0.08 0.16 1.004 0.07 0.25 0.81 1.00

6 0.07 0.13 0.99 0.70 1.00

rt system activity; EST, esterase enzyme; BC, bacterial carbon.

tionReferences

Alef, K., Nannipieri, P., 1995. Enrichment, isolation and counting of soilmicroorganism. In: Methods in Applied Soil Microbiology and Biochemistry.Academic press, pp. 123186.

Amador, E.S., 1980. Assoreamento da Baa de Guanabara taxas de sedimentao.Anais da Academia Brasileira de Cincias 52, 723742.

Baptista Neto, J.A., Smith, B.J., McAlister, J.J., 2000. Heavy metal concentrations insurface sediments in a nearshore environment, Jurujuba Sound, SoutheastBrazil. Environmental Pollution 109, 19.

Baptista Neto, J.A., Crapez, M.A.C., McAlister, J.J., Vilela, C.G., 2005. Concentrationand bioavailability of heavy metals in sediments from Niteri harbour(Guanabara Bay/S.E. Brazil). Journal of Coastal Research 20, 17.

Baptista Neto, J.A., Gingele, F.X., Leipe, T., Brehme, I., 2006. Spatial distribution ofheavy metals in supercial sediments from Guanabara Bay: Rio de Janeiro,Brazil. Environmental Geology 49, 10511063.

Baumgartner, L.K., Reid, R.P., Dupraz, C., Decho, A.W., Buckley, D.H., Spear, J.R.,Przekop, K.M., Visscher, P.T., 2006. Sulfate reducing bacteria in microbial mats:changing paradigms, new discoveries. Sedimentary Geology 185, 131145.

Brito, E.M.S., Guyoneaud, R., Goi-Urriza, M., Ranchou-Peyruse, A., Verbaere, A.,Crapez, M.A.C., Wasserman, J.C.A., Duran, R., 2006. Characterization ofhydrocarbonoclastic bacterial communities from mangrove sediments inGuanabara Bay, Brazil. Research in Microbiology 157, 752762.

Burone, L., Muniz, P., Pires-Vanin, A.M., Rodrigues, M., 2003. Spatial distribution oforganic matter in the surface sediments of Ubatuba Bay (Southeastern Brazil).Anais da Academia Brasileira de Cincias 75, 7790.

Byers, S., Mills, E., Stewart, P., 1978. Comparison of methods of determining organiccarbon in marine sediments, with suggestions for a standard method.Hydrobiologia 58, 4347.

Carlucci, A.F., Craven, D.B., Robertson, D.J., Willians, P.M., 1986. Surface-lmmicrobial populations diel amino acid metabolism, carbon utilization andgrowth rates. Marine Biology 92, 289297.

Carreira, R.S., Wagener, A.L.R., 2003. Caracterizao da matria orgnica sedimentarna Baa de Guanabara atravs de marcadores moleculares. Anurio do Institutode Geocincias UFRJ 26, 7991.

Carreira, R.S., Wagener, A.L.R., Readman, J.W., 2004. Sterols as markers of sewagecontamination in a tropical urban estuary (Guanabara Bay, Brazil): space timevariations. Estuarine Coastal and Shelf Science 60, 587598.

Catanzaro, L.F., Baptista-Neto, J.A., Guimares, M.S.D., Silva, C.G., 2004. Distinctivesedimentary processes in Guanabara Bay SE/Brazil, based on the analysis ofecho-character (7.0 kHz). Revista Brasileira de Geofsica 22, 6983.

Colombo, J.C., Silverberg, N., Gearing, J.N., 1996. Biogeochemistry of organic matterin the Laurentian trough, II. Bulk composition of the sediments and relativereactivity of major components during early diagenesis. Marine Chemistry 51,295314.

Cowie, G.L., Hedges, J.I., 1992. The role of anoxia in organic matter preservation incoastal sediments: relative stabilities of the major biochemicals under oxic andanoxic depositional conditions. Organic Geochemistry 19, 229234.

Crapez, M.A.C., Tosta, Z.T., Bispo, M.G.S., Pereira, D.C., 2000. Acute and chronicimpacts caused by aromatic hydrocarbons on bacterial communities at BoaViagem and Forte do Rio Branco Beaches, Guanabara Bay, Brazil. EnvironmentalPollution 108, 291295.

Crapez, M.A.C., Cavalcante, A.C., Bispo, M.G.S., Alves, P.H., 2001. Distribuio eatividade enzimtica de bactrias nos limites inferior e superior entre-mars naPraia de Boa Viagem, Niteri, R.J., Brasil. In: Moraes, R. et al. (Eds.), Efeito depoluentes em organismos marinhos, So Paulo, Arte e Cincia, Villipress, pp.129138.

Crapez, M.A.C., Baptista Neto, J.A., Bispo, M.G.S., 2003. Bacterial enzymatic activityand bioavailability of heavy metals in sediments from Boa Viagem Beach(Guanabara Bay). Anurio do Instituto de Geocincias UFRJ 26, 5864.

Crapez, M.A.C., 2009. Bactrias marinhas. In: Pereira, R.C., Soares-Gomes, A. (Org.),Biologia Marinha, second ed., Editora Intercincia, Rio de Janeiro, pp. 183212.

Crapez, M.A.C., 2008. Microorganismos. In: Baptista Neto, J. A., Wallner-Kersanach,M., Patchineelam, S.M. (Org.), Poluio Marinha, Intercincia, Rio de Janeiro, p.21.

Da Silva, F.S., Pereira, D.C., Nuez, L.S., Krepsky, N., Fontana, L.F., Baptista Neto, J.A.,Crapez, M.A.C., 2008. Bacteriological study of the supercial sediments ofGuanabara Bay, RJ, Brazil. Brazilian Journal of Oceanography 56, 1322.

Danovaro, R., Dellanno, A., Pusceddu, A., Fabiano, M., 1999. Nucleic acidconcentrations (DNA, RNA) in the continental and deep sea sediments of theeastern Mediterranean: relationships with seasonally varying organic inputsand bacterial dynamics. Deep-Sea Research I 46, 10771094.

DellAnno, A., Mei, M.L., Pusceddu, A., Danovaro, R., 2002. Assessing the trophic stateand eutrophication of coastal biochemical composition of sediment organicmatter. Marine Pollution Bulletin 44, 611622.

Demaison, G.J., Moore, G.T., 1980. Anoxic environments and oil source bed genesis.Organic Geochemistry 2, 913.

Dubois, M., Gilles, K., Hamilton, J.K., Rebers, P.A., Smith, F., 1956. Colorimetricmethod for determination of sugars and related substances. AnalyticalChemistry 28, 350356.

Edwards, K.J., Bach, W., McCollom, T.M., 2005. Geomicrobiology in oceanography:microbemineral interactions at and below the seaoor. Trends Microbiology

1680 L.F. Fontana et al. /Marine Pollu13, 449455.Emerson, S., Fischer, K., Reimers, C., Heggie, D., 1985. Organic carbon dynamics and

preservation in deep-sea sediments. Deep-Sea Research 32, 121.Fabiano, M., Danovaro, R., Fraschetti, S., 1995. A three-year time series of elementaland biochemical composition of organic matter in subtidal sediments of theLigurian Sea (northwestern Mediterranean). Continental Shelf Research 15,14531469.

FEEMA, 1990. Projeto de recuperao gradual da Baa de Guanabara, vol. 1.Fundao Estadual de Engenharia do Meio Ambiente, Rio de Janeiro, RJ, Brazil. p.203.

Fenchel, T., King, G.M., Blackburn, T.H., 1988. Bacterial Biogeochemistry: TheEcophysiology of Mineral Cycling, second ed. Academic Press, Berlin. p. 307.

Fiordelmondo, C., Pusceddu, A., 2004. Short-term response of benthic bacteria andnanoagellates to sediment resuspension: an experimental study. Chemistryand Ecology 20, 107121.

Flemming, B.W., 2000. A revised textural classication of gravel-free muddysediments on the basis of ternary diagrams. Continental Shelf Research 20,11251137.

Fontana, L.F., Da Silva, F.S., Figueiredo, N.G., Brum, B.M., Pereira Netto, A.D.,Figueiredo Jr., A.G., Crapez, M.A.C., submitted for publication. Supercialdistribution of aromatic substances and geomicrobiology of sediments fromSuru Mangrove, Guanabara Bay, RJ, Brazil. Anais da Academia Brasileira deCincias.

Furukawa, K., Wolanski, E., Mueller, H., 1997. Currents and sediment transport inmangrove forests. Estuarine Coastal Shelf 44, 301310.

Gerchacov, S.M., Hatcher, P.G., 1972. Improved technique for analysis ofcarbohydrates in sediment. Limnologia Oceanography 17, 938943.

Hartree, E.F., 1972. Determination of proteins: a modication of the Lowry methodthat gives a linear photometric response. Analytical Biochemistry 48, 422427.

Henrichs, S.M., 1992. Early diagenesis of organic matter in marine sediments:progress and perplexity. Marine Chemistry 39, 119149.

Houri-Davignon, C., Relexans, J.-C., 1989. Measurement of actual electron transportsystem (ETS). Activity in marine sediments by incubation with INT.Environmental Technology Letters 10, 91100.

Keil, R.G., Montlucon, D.B., Prahl, F.G., Hedges, J.I., 1994. Sorptive preservation oflabile organic matter in marine sediments. Nature 370, 549552.

Kepner Jr., R.L., Pratt, J.R., 1994. Use of uorochromes for direct enumerations oftotal bacteria in environmental samples: past and present. MicrobiologicalReviews 58, 603615.

Kjerfve, B., Ribeiro, C., Dias, G., Filippo, A., Quaresma, V., 1997. Oceanographiccharacteristics of an impacted coastal bay: Baa de Guanabara, Rio de Janeiro,Brazil. Continental Shelf Research 17, 16091643.

Krekeler, D., Cypionka, H., 1995. The preferred electron acceptor of Desulfovibriodesulfuricans. CSN FEMS in Microbiology and Ecology 17, 271278.

Lee, C., Wakeham, S., Arnosti, C., 2004. Particulate organic matter in the Sea: thecomposition conundrum. Royal Swedish Academy of Science 33, 565575.

Marsh, J.B., Wenstein, D.B., 1966. A simple charring method for determination oflipids. Journal of Lipids Research 7, 574576.

Meyer-Reil, L.A., 1994. Microbial life in sedimentary biolms the challenge tomicrobial ecologists. Marine Ecology Progress Series 112, 303311.

Meyer-Reil, L.A., Kster, M., 2000. Eutrophication of marine waters: effects onbenthic microbial communities. Marine Pollution Bulletin 41, 255263.

Mitchel, J., 2000. Assessment and recommendations for the oil spill cleanup ofGuanabara Bay, Brazil. Spill Science and Technology 6, 8996.

Pinturier-Geiss, L.L., Mejanelle, L., Dale, B., Karlsen, D.A., 2002. Lipids as indicators ofeutrophication in marine coastal sediments. Journal of Microbiological Methods48, 239257.

Premuzic, E.T., Benkovitz, C.M., Gaffney, J.S., Walsh, J.J., 1982. The nature anddistribution of organic matter in the surface sediments of world oceans andseas. Organic Geochemistry 4, 6377.

Pusceddu, A., Sara, G., Armeni, M., Fabiano, M., Mazzola, A., 1999. Seasonal andspatial changes in the sediment organic matter of a semi-enclosed marinesystem (W-Mediterranean Sea). Hydrobiologia 397, 5970.

Relexans, J.C., Lin, R.G., Castel, J., Etcheber, H., Laborde, P., 1992. Response of biota tosedimentary organic matter quality of the West Gironde mud patch, Bay ofBiscay (France). Oceanologica Acta 15, 639649.

Ribeiro, L.G.L., Carreira, R.S., Wagener, A.L.R., 2008. Black carbon contents anddistribution in sediments from the Southeastern Brazilian Coast (GuanabaraBay). Journal of the Brazilian Chemical Society 19, 12771283.

Rice, D.L., 1982. The detritus nitrogen problem: new observations and perspectivesfrom organic geochemistry. Marine Ecology Progress Series 9, 153162.

Sepers, A.B.J., 1981. Diversity of ammonifying bacteria. Hydrobiologia 83, 343350.

Shivaraman, N., Shivaraman, G., 2003. Anammox a novel microbial process forammonium removal. Current Science 84, 15071508.

Soares, M.L.G., Silva Jr., C.M.G., Cavalcanti, V.F., Almeida, P.M.M., Monteiro, A.S.,Chaves, F.O., Estrada, G.C.D., Barbosa, B., 2006. Regenerao de oresta demangue atingida por leo na Baa de Guanabara (Rio de Janeiro, Brasil):Resultados de 5 anos de monitoramento. Geochemistry Brasiliensis 20, 5477.

Stubbereld, L.C.F., Shaw, P.J.A., 1990. A comparison of tetrazolium reduction andFDA hydrolysis with other measures of microbial activity. Journal ofMicrobiology Methods 12, 151162.

Trevors, J., 1984. Effect of substrate concentration, inorganic nitrogen, o2concentration, temperature and pH on dehydrogenase activity in soil. WaterResearch 77, 285293.

Bulletin 60 (2010) 16741681Tselepides, A., Polychronaki, T., Marralle, D., Akoumianaki, I., DellAnno, A.,Pusceddu, A., Danovaro, R., 2000. Organic matter composition of the

continental shelf and bathyal sediments of the Cretan Sea (NE Mediterranean).Progress in Oceanography 46, 311344.

Turner, A., Millward, G.E., 2002. Suspended particles: their role in estuarinebiogeochemical cycles. Estuarine, Coastal and Shelf Science 55, 857883.

Valentin, J., Tenenbaum, D., Bonecker, A., Bonecker, S., Nogueira, C., Paranhos, R.,Villac, M.C., 1999. Caractristiques hydrobiologiques de La Baie de

Guanabara (Rio de Janeiro, Brsil). Journal du Recherche Ocanographique24, 3341.

Weiss, M.S., Abele, U., Weckesser, J., Welte, W., Schiltz, E., Schulz, G.E., 1991.Molecular architecture and electrostatic properties of a bacterial porin. Science254, 16271630.

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Geomicrobiology of cores from Suru Mangrove Guanabara Bay BrazilIntroductionMaterials and methodsResults and discussionConclusionReferences