Repositório RCAAP

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

The existence of an urban gradient can influence the distribution of the local avifauna. The objectives of this work were: 1. to establish distribution (space and time) of the avifauna in a section of the urban area of Uberlândia; 2. to estimate the richness and the contact frequency of the species found in the study area; 3. to determine the existence of an urban gradient along the area and 4. to evaluate the influence of environmental parameters on the distribution of the avifauna in that gradient. They were established nine transects along three avenues of the city, disposed parallely, that are prolonged from the periphery to the center. The corners were considered observation points. The avifauna was reasearched between October of 2003 and August of 2004. The observations were accomplished about 30 minutes after dawning, in sessions of eight minutes for point. The registrations of the species were visual and/or acoustic. The number of contacts was establish through the counting method for points. The species Columba livia, Notiochelidon cyanoleuca and Passer domesticus were not counted. The registered species were classified as for the occurrence frequency. The transects were sampled in nine days a month, a totality of 432 points (57,6 hours). The urban gradient was characterized by amount of houses, buildings, urban trees, lamp posts and fallow lands, as well as the distance of each point. We found 56 species of birds (10 orders, 21 families and 49 generes). The rainy station presented larger richness (51 species) and larger number of exclusive species (n = 5). The resident species (n = 31) acted more than 55% of the registered birds. In the total, 3,746 contacts were registered. The stations differed statisticaly as for the number of contacts: 1,516 in the rainy station and 2,230 contacts in the dry station. Fourteen species of birds were classified as common (registered in all of the months), representing 88,3% of the total of registrations (n = 3,311). The initial points of the transectos presented larger number of trees and fallow lands. Richness showed significant relationship with the distance of the points to the center. Among the quantified environmental variables, those that demonstrated the existence of the urban gradient were: urban trees, fallow lands and buildings; while buildings between an and five floors, fallow lands and lamp posts had larger weight about the distribution of the avifauna.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

The caprellid amphipods are small crustaceans, usually with 0.1 to 3 cm long, belonging to the suborder Caprellidea. The caprellids have an important ecological function, because in addition to providing the connection between primary producers and higher trophic levels, they are sensitive to environmental variations, toxins and pollutants. Among these pollutants, organotin compounds, such as the tributyltin (TBT) stands out. The TBT is commonly used as active ingredient in biocides. Its wider application, however, is in the hulls of vessels due to its anti-fouling effect. Due to these factors, TBT and its derivatives (dibutyltin - DBT and monobutyltin - MBT) have caused environmental contamination in the marine environment, especially in the sediment and water, from areas with high boat traffic, like marinas and harbors. As the detection limits of organotins, such as TBT, through the normal analytical methods are relatively high, the use of marine organisms in the monitoring of these compounds are interesting because, besides accumulating these compounds, lower trophic level organisms such as caprellid amphipods, have higher concentrations of TBT. Therein, the aim of this study was evaluate the potential use of caprellids as bioindicators of OTs in the northern coast of São Paulo State. For this, two samplings were performed (December 2009 and March 2010) at three beaches (Fortaleza, Lázaro and Lamberto) from Ubatuba, SP. Ten individual fronds of Sargassum were collected per beach in each period to characterize the structure of caprellid assemblages. The environmental conditions of the beaches were evaluated by measurements of hydrodynamics, temperature, dissolved oxygen, turbidity and organic matter in water. The fronds were fixed, washed and examined and the organisms were identified to species level. For organotin evaluation, fifty fronds of Sargassum were collected, per beach, in each sampling period, from which caprellids were removed for analysis. In laboratory, the caprellids were stored in aluminum foil, frozen and sent to the organotin compounds analysis. The samples were then homogenized, and passed through an analytical procedure before analysis in a gas chromatography with pulsed flame photometric detector (GC-PFPD). To describe the caprellid assemblages, the density, species richness and indexes of diversity and evenness were calculated. Some differences in environmental conditions among beaches and between sampling periods were recorded. A total of 384 caprellids of nine different species were collected. The Lázaro beach had the highest density, richness, and diversity. Despite this species richness, only two species (Caprella danilevskii and Caprella dilatata) could be used in the organotin analyses, because of the amount of mass required by the method. High concentrations of TBT were found in the samples of C. danilevskii (above 200 ng Sn/g), whereas for C. dilatata the values were from below the detection limit up to 35 ng Sn/g. It is expected that with the implementation of new legislation in Brazil, there is a decrease in concentrations of TBT in the coastal areas of the country. However, the monitoring of TBT concentrations is still needed and the results obtained indicate that caprellids C. danilevskii stands out as an efficient bioindicator of TBT contamination in littoral north of São Paulo and another areas of Brazilian littoral, because this species besides concentrating this compound, can be easily collected, occurs in a wide variety of environmental conditions and is widely distributed in the country.

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Universidade Federal de Uberlândia

The Brazilian Merganser (Mergus octosetaceus) is a critically-endangered species whose largest wild populations can be found at conservation units in Brazil. Habitat loss and degradation due to anthropic interference are the main threats to its survival. I used nine different niche modeling algorithms to build a consensus model composed of the best five models to predict Mergus octosetaceus potential geographical distribution in Brazil. I also employed a multicriteria analysis technique (weighted linear combination) in a GIS environment to map anthropic pressure levels over the species potential range. Modeling of the potential geographical distribution resulted in a habitat suitability map which indicated 17.3% of the national territory as suitable to occurrence of M. octosetaceus. Two hundred and nineteen integral protection conservation units were identified as protecting 2.66% of the species potential range. Besides indicating new potential occurrence areas, the habitat suitability map confirmed current and historical occurrence records. Application of the weighted linear combination resulted in a map of three anthropic pressure levels (low, medium, and high), with high level prevailing over 40.8% of M. octosetaceus potential range. Brazilian Merganser s occurrence points tended to be associated with areas of low anthropic pressure, supporting the notion that interference of anthropic factors lead to its exclusion from altered habitats.

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Universidade Federal de Uberlândia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior