The thesis comprises a classification and analysis of 64 tales told by Indian inhabitants of the rural communities around the highland town of Canar, Southern Central Ecuador, The informants all had Quichua as their mother tongue and, with the exception of 4 texts, used it in the telling of the tales. These were tape-recorded, transcribed with the help of a Quichua assistant, and are presented in full together with English translations. The classification of texts is based largely upon criteria of contents, although both genre and tale structure are also taken into account, all three considerations being closely interrelated. Classification according to content owes something of theory and method to the Finnish-American school led by Aarne and Thompson (Thompson 1955-58, Aarne and Thompson 1951). The discussion of genre definition takes Bascom's article (1965) as a starting point, and also takes into account more recent statements on the subject. The consideration of structure as a criterion at the classification stage is in accordance with the arguments of Propp (1968) and Dundes (1962b, 1964). The classification scheme resulted in a breakdown of the tales into four sections (A-D), The largest of these is Section A, whose 32 tales will be shown to adhere to a common structural framework, whilst the sub-sections into which they are divided reflect their differences in surface content. Sections B and C are both examples of tale cycles, bound by this definition to be grouped together. Section D comprises humorous tales, largely borrowings from mestizo culture, with little in common on grounds of structure. The analysis seeks to examine the relationship between tales within the sections, at the levels of both structure and content if this is appropriate; where it is not, remarks are confined to content alone. The analysis of both structure and content calls for some comparisons to be drawn with material from elsewhere. Such comparisons are confined to the Ecuadorean highlands, to a lesser extent Peru, and incidental reference is made to other geographical areas, especially where borrowings are concerned, Structural analysis was most applicable to Section A, an apparently heterogeneous group of legends and folktales which, it is argued, are bound together by common underlying features of structure. These features appear to derive from the local legends of the area, and have then encouraged the adoption and development of certain folktales whose structure was compatible with such already existing forms. The theoretical basis for this approach is to be found in Dundes (cit.), Maranda and Kongas Maranda (1971), and Hymes (1971). The breakdown of texts to reveal their structure takes both the 'syntagmatic' and the 'paradigmatic' aspects of the latter into account (see Dundee's intro, to Propp 1968:xi-xii). In order to reveal more clearly the paradigmatic characteristics of the texts, and the structural affinities that exist between tales at this level, use is made of Levi-Straussian terminology and the methods he uses for the schematic cross-comparison of tales have been adapted (Levi-Strauss 1970, 1972), Analysis of content follows two main lines: in the case of the legendary material it is particularly appropriate to examine the relationship that apparently exists between the local belief system and oral narrative. In the case of folktales, it is relevant to consider content on comparative lines, examining the nature and/or distribution of episodes as they occur in Canar and as they are found elsewhere in Andean narrative tradition. The works of Morote Best were particularly useful for this purpose (1950b, 1953b, 1954, 1957, 1958a, 1958b). The main aim of the thesis is therefore to analyse the structure and content of the tales in order to show the underlying relationships that bind them within a coherent system of narrative tradition. Some connections at both these levels are also to be seen between sections as well as within them, and these are pointed out. Material introduced from outside was adopted, it is suggested, for its compatibility with that which was already there. In addition to this, possible social and cultural reasons for the appeal of particular kinds of tale in the area are discussed as relevant.

Doctor of Philosophy / Department of Civil Engineering / David Steward / Western Kansas has a semi-arid climate where the demand for water resources is greater than the natural supply. To meet the demand for irrigated agriculture, the groundwater has been extracted at a rate greater than the natural recharge rate, resulting in declining water table in the aquifer and reduced streamflow in the rivers and streams in the region. An assessment of the rivers in western Kansas was conducted to determine the fluxes between the river, groundwater, and the atmosphere. Riverbeds were instrumented to determine the conductivity of the riverbed sediments, the transmission losses of the Arkansas River were modeled to determine the interactions between the surface water and groundwater, and the evapotranspiration of the Arkansas River corridor was estimated using satellite remote sensing to quantify of water lost to the atmosphere. The Arkansas River and Cimarron River are shown to have a high hydraulic conductivity and a large infiltration capacity at the surface of the riverbed. However, the large surface infiltration capacity does not translate into large transmission losses, which are a fraction of the rate of the surface infiltration capacity of the riverbed. Thus, surface infiltration is only one factor of what controls the transmission losses. It is shown that transmission losses for a connected river-aquifer system are driven by induced infiltration by riparian vegetation. The interactions between the surface, groundwater and atmosphere were assessed over time, revealing that the flux to the atmosphere can be decoupled from the Arkansas River discharge and the groundwater recharge. While the declining discharge in the Arkansas River can be attributed to the extraction of groundwater resources and the management of surface water resource, the atmospheric fluxes are independent of the surface water and groundwater at an annual scale. When the river ecosystem is water stressed, the trees continue to draw water. This points to both the reliable store of water from the alluvial aquifer and the ability of the tree community to respond to water stress. While the water in the alluvial deposits are currently being lost from the system through evapotranspiration, this provides a potential store for consideration in future water management decisions.

This study documents the stage adjustments in the Lower White River between 1931 and 2012 at four rated gaging stations along the trunk stem of the river. The study reach extends from Calico Rock, Arkansas, to the confluence of the White River with the Mississippi River north of Arkansas City, a distance of about 509 km. The specific gage approach was used to track hydrological response in the study reach. In order to approach spatial homogeneity across the four gaging locations along the study reach, input discharges were normalized to multiples of mean daily flow (MDF). Specific gage analysis tracks water surface elevation changes for fixed discharge conditions over time. Three discharges were analyzed at each station: low flow, mean flow, and high flow. The low flow specific gage trends are emphasized to highlight degradation and aggradation due to the sensitivity of specific stages at low flows to channel bed elevation changes. An `enhanced interpolation' technique was used to fill gaps in the specific stage time series in order to avoid errors derived from extrapolation of annual rating curves. The analysis shows decreasing trends in specific stage at Clarendon and DeValls Bluff at low flows, indicating net degradation. The gages at Newport and Calico Rock show increasing trends in specific stage over time at low flows, indicating aggradation downstream of Norfork and Bull Shoals reservoirs.

During the past decade, a series of record flood stages have occurred along the Tisza River, resulting in extensive damage and displacing the local floodplain population. Previous research on the Tisza River in Hungary showed increases in flood stages for fixed discharges (above bankfull). These results suggest that a loss of conveyance has taken place on the Tisza River, contributing to recent record flood levels. In order to assess the potential causes of flood conveyance losses, new hydrological and geospatial data were obtained from the Hungarian Federal Hydrological Authority (VITUKI) in order to develop hydrodynamic models for two reference conditions, 1979 and 1999, along two study reaches on the Middle Tisza River. In addition to these models of actual conditions at each time step (i.e., "retro-models"), four "scenario models" were developed in order to test the individual impacts of each of the hypothesized causal mechanisms: 1) channel geometry, 2) levees, 3) floodplain roughness (land cover), and (4) channel roughness. Comparison of the models for actual conditions ("retro-model") and the scenario models allows for quantitative assessments of the impacts of each of these parameters on flood conveyance. In addition to these four scenario models, an additional land cover scenario-model was created to further assess the impact of floodplain roughness on stage. Assessment of the two retro-models showed changes in flood stage along both study reaches over the 20-year time step. Along the upper study reach, changes in stage ranged between 0.64 and 1.64 m. On the lower study reach, changes in stage ranged from 0 to 1.75 m. These changes in stage were larger on average than changes in stage previously detected by Venzcel, 2008. Contributions from the channel geometry scenario model were significant on the upper study reach where channel geometry decreased flood stage by up to 0.58 m at Kisköre over the 20-year time step. This was attributed to the dam that was constructed immediately upstream from the Kisköre gauge on the upper study reach. Construction of a dam would cause incision downstream, and therefore, a decrease in flood stage over time due to channel geometry. On the lower study reach, change in stage due to channel geometry was negligible. Contributions from the levee scenario model were negligible on both the upper and lower study reach with a maximum change in stage over the 20-year time step at only 0.11 m. However, during the time step analyzed, no significant change in levee configuration occurred. Changes in stage due to changes in land cover were also negligible along both study reaches. An additional land cover scenario model was created to assess the impact of land cover change on modern flood levels. This scenario model set Manning's n values for floodplain roughness to 0.04, which approximates roughness for pasture and cropland. This scenario model showed that flood stages will decrease by 0.34-0.40 m, but only if the entire floodplain is converted from woodland to pasture/cropland. Channel roughness accounted for the majority of change in stage during the 20-year time step. Along the upper study reach, channel roughness accounted for an average of 1.51 m of change over the 20-year time step. On the lower study reach, channel roughness accounted for 1.03 m of change. Change in the stage/discharge relationship is the best explanation for changes in stage due to channel roughness. Most likely, the channel did not experience such a large change in roughness during the 20-year time step. Instead, the two flood years used in this analysis were different "types" of floods (with differing degrees of hysteresis), and the stage/discharge relationships could not be easily compared. Comparing these two floods may have exaggerated the total change in stage between the two retro-models. Backwater effects are a likely explanation for the change in hysteresis between the two flood years.

The Cache River, located in southern Illinois, faces a unique set of restoration challenges due to multiple anthropogenic modifications to the watershed. In 1915 the Cache River was disconnected and divided into two sub-watersheds, the upper Cache River (UCR) and the lower Cache River (LCR). This alteration has led to impairments in both sections of the Cache River. The UCR currently suffers from channel incision and wetland loss due to an increase in channel slope, while the LCR experiences decreased flows and related habitat degradation. Currently, watershed managers are proposing to restore a more natural flow regime to the LCR through some degree of hydrologic reconnection. I quantified the effects of small-scale differences in flow velocities on snag-dwelling aquatic macroinvertebrates in the UCR and LCR. My study was designed to provide critical information on potential ecological responses to proposed reconnection of the Cache River by examining the effects of flow on elements of ecosystem structure (macroinvertebrate community structure, diversity, richness, evenness, biomass, and abundance) and function (secondary production). Total snag-dwelling macroinvertebrate abundance was higher in the LCR (p < 0.001), and both total biomass and total production did not differ between the UCR and LCR. Passive filter-feeders (families Hydropsychidae and Simuliidae), EPT taxa (orders Ephmeroptera Plecoptera and Trichoptera), and Elmidae were more abundant and had higher biomass on snags in the UCR compared to the LCR. Due to high variability in estimates, only Elmidae production was higher in the UCR (p < 0.05), with non-significant trends of higher production of passive filter-feeders and EPT taxa in the UCR. Non metric multidimensional scaling (NMDS) ordinations showed different communities on snags in the UCR and LCR, and analysis of similarity indicated these differences were significant (ANOSIM Global R = 0.98, p < 0.05). This UCR community was more diverse (p < 0.05) and composed of larger-sized individuals than the LCR (p < 0.001). In contrast, the LCR community was composed mainly of taxa that are associated with very low flows (e.g., zooplankton), tolerant of degraded conditions (e.g., Isopoda and Chironomidae), and generally smaller in body size. Although not statistically significant, there was a trend for higher total production in the LCR (28.90 ± 54.51) (mean ± 95% CI) than the UCR (10.22 ± 6.43). This trend was driven primarily by a patchily distributed Chironomidae, which were highly productive on some LCR snags. However, given the degraded water quality in the LCR, the ultimate fate of this production is not clear. The more natural flow regime in the UCR is likely driving many of the differences between the UCR and LCR that I observed, but relationships may be complex, as flow influences biota in numerous direct and indirect ways. This study is the first I know of to examine the structure and function of macroinvertebrate communities prior to hydrologic restoration of a river. Results will assist resource managers in the justification, planning, and execution of hydrologic restoration in the Cache watershed. Given that many river restoration projects are not based on sound ecological information and principles, this project can also serve as a model for future river restoration efforts.

The introduction and spread of two Asian Carp species, Bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix have caused severe ecological damage throughout North America. Currently, academic institutions, and state and federal agencies are investigating ways of controlling the spread of these species and managing existing populations to minimize further damage. One promising method of control is the commercial harvest of Asian carps for export to China, as both species are highly valued foodfish throughout Asia. Habitat modification and destruction, along with the questionable quality of fish produced in aquaculture facilities throughout China, have caused members of the foodfish industry to search elsewhere for a high quality product destined for middle and upper class consumers in China. At this time, harvest practices are not standardized, and taking market potential into consideration, it is important to optimize aspects of harvest so commercial fishermen and processors can supply consumers with the highest quality product. Therefore, the present studies evaluated the effects of season (summer and fall), geographic origin (Alton and Peoria Reach), and harvest gear type (trammel nets and hoop nets) on commercially caught fresh fish and those subjected to standard processing practices and simulated shipping conditions to China (blast frozen to core temperatures near - 33oC and stored at- 20oC for 6 wk) using quality evaluation methods common in the foodfish industry. Impacts of season, geographical origin, and gear type on fresh Bighead and silver carp were assessed using fillet internal and external pH, color, Torrymeter freshness, and proximate analysis (percent moisture, protein, lipid, and ash). The effects of season, geographical origin, and gear type on fish processed and held under simulated shipping conditions were analyzed using fillet internal and external pH, color, Torrymeter freshness, K value, and peroxide and aldehyde concentrations. Results indicate negligible effects of season of harvest or geographical origin on final quality of Asian carp products, but the optimization of Asian carp products may require only exporting Bighead carp. Hoop nets yielded better quality fish overall, indicating that commercial fishermen should consider using these specifically for the harvest of fish destined for human consumption. Information assembled in this research can be used by commercial fishermen and processors to develop standardized methods for the harvest of Asian carps. Providing a high quality product is vital considering market potential and the resulting economic stimulation provided to fiscally starved areas where these facilities are located. Most importantly, the development of this industry could, in conjunction with continued academic and agency efforts, offer an independent solution to the serious ecological threat posed by these species.

River otter (Lontra canadensis) populations in Illinois have rebounded considerably after >80 years of harvest protection and a successful reintroduction program. However, few studies of river otter ecology exist in the Midwestern U.S. where river otter numbers have increased in recent decades. Capturing study animals safely and efficiently is a critical part of wildlife research, and difficulties associated with live capture of river otters have contributed to the dearth of research on the species. Furthermore, estimating survival rates and identifying causes of mortality are important in effectively managing river otters. To address these knowledge gaps, my objectives were determine survival rates and mortality causes for river otters in southern Illinois, and to measure injury rates of river otters captured using Comstock traps. During 2014-16, I captured 42 river otters 49 times at Crab Orchard National Wildlife Refuge (CONWR) in southern Illinois. Eight river otters (3 M, 5 F) were captured in foot-hold traps during 788 trap nights (1 capture/88 trap nights), and the remaining 34 (19 M, 15 F) were captured in Comstock traps during 2,540 trap nights (1 capture/64 trap nights). I detected no significant differences in efficiency or escape rate between the 2 trap types, but Comstock traps did have higher rates for both unavailability and non-target captures. Eleven of the 20 river otters inspected for injuries received some type of injury as a result of capture in a Comstock trap (55%). The most common injury was claw loss (45%), followed by tooth fracture (25%), and lacerations (10%). The ease of setting the Comstock traps and of releasing non-target captures made them a more appealing option than foot-hold traps; however, river otters have a propensity for doing permanent damage to their teeth when live captured in Comstock traps. My study provides information on the functionality and safety of a novel live capture method for river otters. Thirty-four (16 F, 18 M) river otters were successfully radio-marked and monitored for survival for a total of 8,235 radio-days (¯x days/river otter = 242.2 ± 20.6 [SE throughout]). Two river otters (2 M) died during the period of radio-telemetry monitoring: 1 was trapped during nuisance wildlife control activities at an adjacent fish hatchery, and the other died of unknown causes. Annual survival rates were 1.0 ± 0.00 (lower confidence bound = 0.83) and 0.85 ± 0.09 for females and males, respectively, and similar between sexes (χ_1^2 = 1.7, P = 0.19). Pooled-sex breeding season survival was 0.96 ± 0.04. Trapping was the primary source of mortality over the course of my study. After radio-telemetry ended, 2 river otters were harvested by recreational trappers, at 114 (1 M) and 120 (1 F) weeks post-capture, and 1 male was killed by a vehicle collision at 52 weeks post-capture. Primary mortality sources for river otters in southern Illinois are similar to those reported elsewhere (i.e., trapping and vehicle collisions). Although I found no significant difference in survival rates between sexes, the majority of otters that died during my study were male (4 M, 1 F). As river otters occupying CONWR are protected from harvest, males may be more likely to leave the confines of CONWR, thereby putting themselves at greater risk to recreational trapping mortality. My study provides useful demographic information for Illinois’ recently-recovered river otter population.

The Miocene to Pliocene southern Bouse Formation preserves a record of depositional environments immediately prior to and during integration of the Colorado River to the Gulf of California. Uncertainty over Bouse paleoenvironments obscures our understanding of the timing and magnitude of regional uplift, as well as the conditions and processes that were active during integration and early evolution of the Colorado River. Prior studies over the past 20 years have concluded that the southern Bouse Formation accumulated in chain of lakes isolated from the ocean. Sedimentologic analyses presented here aid interpretation of depositional environments and provide evidence for a strong tidal influence on deposition, consistent with a marine interpretation of other prior studies. This interpretation places a critical constrain on the elevation of these deposits at ca. 5 Ma, and suggests post-Miocene uplift of the Lower Colorado River corridor. This thesis includes previously published coauthored material.

SOARES, T. C. M. Variação sazonal, transporte e partição de hg no gradiente fluviomarinho do Rio Jaguaribe - CE. 2011. 102 f. Dissertação (Mestrado em Ciências Marinhas Tropicais) - Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2011. / Submitted by Geovane Uchoa (geovane@ufc.br) on 2016-01-25T14:33:46Z No. of bitstreams: 1 2011_dis_tcmsoares.pdf: 7302588 bytes, checksum: 174e73c49292a683e0c7c609fddb0a45 (MD5) / Approved for entry into archive by Nadsa Cid(nadsa@ufc.br) on 2016-01-25T18:42:38Z (GMT) No. of bitstreams: 1 2011_dis_tcmsoares.pdf: 7302588 bytes, checksum: 174e73c49292a683e0c7c609fddb0a45 (MD5) / Made available in DSpace on 2016-01-25T18:42:39Z (GMT). No. of bitstreams: 1 2011_dis_tcmsoares.pdf: 7302588 bytes, checksum: 174e73c49292a683e0c7c609fddb0a45 (MD5) Previous issue date: 2011 / Coastal environments operate as connections between terrestrial and oceanic environments and in the control of transfers of heavy metals from fluvial waters to the ocean and may cause the deposition of metals associated with suspended material or the release of dissolved form, which completely changes metal vailability to the environment. Hg is an element naturally present in the biosphere, but can also occur via the contamination of the water, biota, soils and atmosphere and is associated with various dissolved or suspended compounds in the aquatic environment, presenting a potential risk to living beings. The partitioning of Hg between the dissolved (Hg-D) and particulate (Hg-P) phases is one of the most important factors to consider in the mobilization and transport of Hg in aquatic systems. In this context, the aim of this work was to analyze the chemistry of Hg partitioning along the estuary of the Jaguaribe river and the adjacent coastal region and estimate the flux of Hg to the adjacent continental shelf through different tidal cycles and seasons and try to identify their controlling factors. Sampling was conducted at two points in the Jaguaribe estuary (Aracati-CE, region with the greatest influence of fresh water, and Fortim-CE, region with the highest marine influence) in the estuarine plume (PE) and the continental platform (PC) and two distinct periods, the rainy season and dry season. For the rainy season, the Hg-D was detectable only in Aracati and in the PE with an average of 10.1 ng.L-1 and 5.6 ng.L-1 respectively. For PC and Fortim the values were lower than the limit of detection (L.D = 0.1 ng.L-1). The average concentration of Hg-P, for the same period was 0.5 ng.L-1 in Aracati, 1.5 ng.L-1 in Fortim, 3.0 ng.L-1 in PE and, 0.12 ng.L-1 in the PC. For the dry season the average concentration of Hg in Aracati was 3.4 ng.L-1; in Fortim was 2.6 ng.L-1, in PE was 0.7 ng.L-1 and in the CP was 2.9 ng.L-1. The average concentration of Hg-P for the same period was 0.25 ng.L-1 in Aracati, 0.38 ng.L-1 in Fortim; 0.18 ng.L-1 in PE and 0.16 ng.L-1 in the PC. The estimated average annual flow of Hg-T from the Jaguaribe river to the continental shelf was ~ 126 kg. The balance between the inflow and output of Hg-T in the estuary indicates that is occurring the retention of this material for the two studied periods. But for the period of lowest discharge the situation is considered more critical, because the retention of Hg is quantitatively larger as well as its residence time in the estuary, increasing the reactivity of the Hg and producing Hg-D, which includes the most bioavailable form of Hg, increasing the possibility of incorporation by the biota and biomagnification in the food chain. / Os ambientes costeiros atuam na ligação entre o ambiente terrestre e oceânico e no controle da transferência de metais pesados presentes nas águas fluviais para as águas oceânicas podendo causar a deposição do metal associado ao material em suspensão ou liberação desse metal, o que modifica a sua disponibilidade para o meio. O Hg é um elemento presente naturalmente, mas também pode entrar na região costeira via contaminação da água, da biota, da crosta terrestre e da atmosfera estando associado a diferentes compostos dissolvidos e em suspensão no ambiente aquático, apresentando risco potencial aos seres vivos. A partição do Hg, portanto, entre as fases dissolvida (Hg-D) e particulada (Hg-P) é um dos mais importantes fatores a serem considerados na mobilização e transporte de Hg em sistemas aquáticos. Nesse contexto, o objetivo do trabalho foi analisar a partição química do Hg ao longo do gradiente fluviomarinho do estuário do rio Jaguaribe e estimar o fluxo continental de Hg para a plataforma continental adjacente através de diferentes ciclos de maré e estações do ano observando identificar seus fatores controladores. A amostragem foi realizada em dois pontos do estuário do rio Jaguaribe (Aracati-CE região com maior influência fluvial e em Fortim-CE região com maior influência marinha), na pluma estuarina (PE) e na plataforma continental (PC) e em dois períodos distintos, período chuvoso e período seco. Para o período chuvoso o Hg-D foi detectável apenas para Aracati e para a PE com média de 10,1 ng.L-1 e 5,6 ng.L-1 respectivamente. Para Fortim e a PC os valores foram menores que o limite de detecção do método (L.D = 0,1 ng.L-1). A concentração média de Hg- P, para o mesmo período foi de 0,5 ng.L-1 em Aracati; 1,5 ng.L-1 em Fortim, 3,0 ng.L-1 para a PE e 0,12 ng.L-1 para a PC. Para o período seco a média da concentração de Hg-D em Aracati foi de 3,4 ng.L-1;em Fortim foi de 2,6 ng.L-1; na PE foi de 0,7 ng.L-1 e na PC foi de 2,9 ng.L-1. A concentração média de Hg-P para o mesmo período foi de 0,25 ng.L-1 em Aracati; de 0,38 ng.L-1 em Fortim; de 0,18 ng.L-1 na PE e de 0,16 ng.L-1 na PC. O fluxo anual médio estimado de Hg-T do rio Jaguaribe para a plataforma continental foi de ~ 126,0 kg. O balanço entre os fluxos de entrada e saída de Hg-T no estuário indica que está ocorrendo uma retenção desse material para os dois períodos estudados. Porém para o período de menor vazão a situação é considerada mais crítica, pois a retenção de Hg é maior quantitativamente assim como também seu tempo de residência no estuário, aumentando a reatividade do Hg produzindo Hg-D, que inclui a forma de Hg mais biodisponível, aumentando a possibilidade de incorporação pela biota e biomagnificação na cadeia alimentar.

CAVALCANTE, M. S. Transporte de carbono orgânico dissolvido no estuário do rio Jaguaribe sob clima semiárido. 2015. 83 f. Dissertação (Mestrado em Ciências Marinhas Tropicais) -Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2015 . / Submitted by Geovane Uchoa (geovane@ufc.br) on 2016-01-26T12:28:17Z No. of bitstreams: 1 2015_dis_mscavalcante.pdf: 2005948 bytes, checksum: 550992dba556517ad3b0cd9b528580b9 (MD5) / Approved for entry into archive by Nadsa Cid(nadsa@ufc.br) on 2016-01-27T20:07:47Z (GMT) No. of bitstreams: 1 2015_dis_mscavalcante.pdf: 2005948 bytes, checksum: 550992dba556517ad3b0cd9b528580b9 (MD5) / Made available in DSpace on 2016-01-27T20:07:47Z (GMT). No. of bitstreams: 1 2015_dis_mscavalcante.pdf: 2005948 bytes, checksum: 550992dba556517ad3b0cd9b528580b9 (MD5) Previous issue date: 2015 / Estuaries are pathway for dissolved organic carbon (DOC) from the coastal to the sea. However, before reaching the ocean, DOC can suffers biogeochemical transformations and influence of estuarine hydrodynamics, which responds to seasonal, and tidal changes. This study analyzed the spatial and temporal variability of DOC, the hydrochemical and physical aspects of Jaguaribe river estuary, under different climate conditions (dry and rainy) and tide (ebb / flood). The spatial variation of the DOC was between 1.1 and 6.4 mg L-1 in the dry season and between 1.1 and 9.15 mg L-1 in the rainy season. There was no great seasonal variability in DOC concentrations, probably due to low levels of rainfall in wet seasons. The hydrogeochemical DOC behavior was different between the seasons. In the dry season, the DOC showed conservative behavior, highly influenced by physical processes because the tidal effects were dominants in the estuary in this season . In the rainy season, the DOC presented non-conservative behavior, linked to biological activity. The DOC was strongly correlated with the residence time and the amount of freshwater, it shows the importance of fluvial descharge to the estuarine DOC input. The values of DOC, freshwater input and residence time increased toward the coastal, indicating retention of freshwater and DOC upstream. The mixing zone of the Jaguaribe River estuary behaved as a DOC retainer in the dry season and as an exporter in the rainy season. The COD flow was lower than expected for areas under semi-arid climate, possibly by rainfall was lower than the historical average. / Os estuários são vias de transporte de carbono orgânico dissolvido (COD) do continente para o mar. Contudo, antes de chegar ao seu destino o COD sofre transformações biogeoquímicas e/ou influência da hidrodinâmica estuarina, que dependem de fatores como clima, descarga fluvial e maré. Este estudo analisou a variação espacial e temporal do COD, a hidroquímica e aspectos físicos do estuário do rio Jaguaribe sob diferentes condições de clima (seco/chuvoso) e maré (vazante/enchente). A variação espacial dos teores de COD foi entre 1,1 e 6,4 mg.L-1 na estação seca e entre 1,1 e 9,15 mg.L-1 na estação chuvosa. Não houve grande variabilidade sazonal dos teores de COD, provavelmente devido ao baixo índice de pluviosidade na estação chuvosa. O comportamento hidroquímico do COD foi diferente entre as duas estações climáticas. Na estação seca, o COD apresentou comportamento conservativo, fortemente influenciado pelos processos físicos devido ao domínio marinho no estuário. Na estação chuvosa, o comportamento não conservativo e mostrou ser fortemente atrelado à atividade biológica. O COD apresentou forte correlação positiva com o tempo de residência (TR) e o percentual de água doce (PAD), mostrando a importância da contribuição fluvial para o aporte de COD no ambiente estuarino. Os valores de COD, PAD e TR foram crescentes em direção ao continente, indicando represamento de águas fluviais e do COD à montante. A zona de mistura do estuário do rio Jaguaribe comportou-se como retentora de COD na estação seca e exportadora na estação chuvosa. O fluxo de COD foi inferior ao esperado para regiões sob clima semiárido, possivelmente pelo regime de chuvas ter sido menor do que a média histórica.