Navegando por Assunto "Formiga (Animal)"

Agora exibindo 1 - 6 de 6

Acesso aberto (Open Access)
Avaliação das comunidades de formigas em uma área de extração madeireira
(Universidade Federal do Pará, 1999-07-30) KETELHUT, Suzana Maria; HARADA, Ana Yoshi; http://lattes.cnpq.br/4410204692155098
This work presents a comparative study of ant fauna communities inhabiting in a primary tropical forest and two types of logging systems (Managed and Traditional) located in Paragominas, PA, Brazil. From each area, ants were sampled using pitfall traps (Majer & Delabie 1994) in six 200m transects separated from each other by 100m. Differences in ant fauna diversity in the three forest types were tested using índices of diversity (Shannon, Simpson and Fisher's Alpha) and richness estimates protocols (Colwell Coddington 1994). Species composition was evaluated through affinity analysis (Scheiner 1992) and indices of similarity (jaccard and Morisita-Horn). A total of 134 ant species belonging to seven subfamilies and 42 genera were identified in the entire area. From these, 90 species were found in Primary Forest, 90 in Managed logged forest and 84 in the Traditional logged Forest. Differences between habitats could be detected by comparing diversity and similarity indices in different transects/habitats. There were no differences in índices when absolute values were compared for each habitat. Results from richness estimate protocols indicate that ant fauna was similar between habitats and suggests that ant fauna diversity was underestimated. Periodic variations on pluviosity had a strong effect on diversity and richness estimates in the three forest types. The ant fauna composition was similar between habitats; however, a high mosaic diversity could be detected by using affinity analysis, suggesting that the ant community is composed of complex gradients. Thus differences in ant composition would be detectable at smaller scales.
Acesso aberto (Open Access)
Diversidade e composição de formigas Ponerines (Hymenoptera, Formicidae, Ponerinae) de Serapilheira na Estação Científica Ferreira Penna, Caxiuanã, Melgaço, Pará, Brasil
(Universidade Federal do Pará, 2009-05-21) BASTOS, Alexandro Herbert dos Santos; HARADA, Ana Yoshi; http://lattes.cnpq.br/4410204692155098
The ponerines, after myrmicines, are the most conspicuous, rich and abundant ground-dwelling ants from tropical rain forests. In this ecosystem the ponerines are ecologically important, since they prey many kinds of invertebrates and nest among leaf litter and rotten logs. In this work the range of leaf litter Ponerinae ants was studied, as well their abundance, richness, diversity, and species composition. In addition, how the litter quantity affect the ponerines range was analyzed. This study was carried out in six primary Amazonian forest areas of 1 Km² (Area I, II, III, IV, V, and VI) at Ferreira Penna Scientific Station (ECFPn), Caxiuanã, Melgaço, Pará state, Brazil. The material was collected at April and October of 2003, and January of 2004, following the Ants Monitoring Protocol of TEAM Iniciative/Caxiuanã Project for the study of leaf litter ants. In each sampled site four transects lines of 100 m (sample units) with 10 samplings points were established. At each sampling point of 1 m², the leaf litter samples were sifted and then placed in mini-Winkler sacks. A total of 4,031 specimens were collected, belonging to three tribes, eight genera, and 60 species of Ponerinae in 470 records. In average 6.52 species were collected per sample. The total richness was estimated in 81 species using first order Jackkinife method. Hypoponera was the most abundant and rich genus, with 22 species in 268 records. The genus Hypoponera plus Pachycondyla showed a strong numerical dominance, with more than 70% of collected species. The Area V was the most diverse (H=3.30), with the highest species richness (38) and abundance (121 records), as well as with the largest amount of leaf litter (ANOVA; p<0,05 between Area V and the other sites). The quantity of leaf litter affected positively the ponerines ants species abundance and richness, and also influenced the species composition. The most common species were: Hypoponera sp#1, Hypoponera sp#2, Hypoponera sp#6, Hypoponera sp#7, Odontomachus scalptus and Pachycondyla constricta. These few species (10%) yielded more than half of total abundance. In short, the ponerines were widely spread in the leaf litter of ECFPn primary forests, being numerically affected by leaf litter volume. The sites showed differences in species diversity, abundance and richness. Furthermore, the species composition of ponerines ants at nearby samples often presented low similarity once high number of species was rare. Thus, the leaf litter availability of Amazonian forest is a key role on species distribution, even at small scales.
Acesso aberto (Open Access)
Does body size of neotropical ant species influence their recruitment speed?
(2013-03) GODOY, Bruno Spacek; CAMARGOS, Lucas Marques de
Ants are one of the most important animal groups in tropical forests because of its abundance and number of species. An important characteristic of the group is the eusociality, which allows the occurrence of a recruitment behavior when food resource is found. However, there are two main questions regarding this behavior: (i) the recruitment is a product of environmental or phylogenetic pressures, and (ii) the recruitment speed is related to the body size of the ant species. In this work we addressed these two questions using 17 species of neotropical ants, in the Amazonic lowland dense rain forest. According to results, recruitment behavior is related to ant size, where smaller species exhibit this trait when finding a protein resource. However, species size is not important in recruitment speed, which suggests that speed can be best explained by the type of food resources needed in the ant colony.
Acesso aberto (Open Access)
Impactos da exploração madeireira sobre a fauna de formigas e conseqüências para a remoção de sementes florestais na Amazônia Oriental
(Universidade Federal do Pará, 2001) KALIF, Kemel Amim Bittencourt; MOUTINHO, Paulo Roberto de Souza; http://lattes.cnpq.br/7277077476036269
Logging in the Amazon Forest affects approximately 1.5 million hectares of forestlands each year. These activities result in forest structural and microclimatic changes that could potentially affect diversity and animal species composition. Regeneration of these areas could be jeopardized since animals disperse most seeds. On the other hand, it is possible not to affect seed dispersal mechanisms by maintaining forest fauna integrity through the implementation of reduced impact logging techniques. By using ants as an ecologically representative animal group and integrated into the regeneration processes through dispersion and predation, this work evaluated; (1) if logging affects fauna (diversity and species composition), (2) if reduced impact logging techniques are capable of preserving it, and (3) if logging affects ants ecological efficiency in seed removal (dispersion and predation). Logging effects on ants' diversity and species composition, as well as seed removal done by these insects, were studied in three different forest areas in the municipality of Paragominas in the state of Pará. The first area was a forest that went through high impact logging (FC), the second a forest affected by reduced impact logging techniques (FB), and the third one a primary forest used as the control group (FP). Ants’ were sampled four times during 1998 using the Winkler method at four transects per area. The seed removal experiment was conducted by distributing seeds of six wood species through twelve points in each area. During the experiment the daily number of ants and other arthropods that visited the seed points was quantified. The amount of seeds removed was counted at the end of the experiment. Diversity and abundance of ant species were not affected by logging activities. However, species composition changed by 36% in FB and by 37% in FC. The Pheidole genus experienced richness and abundance reduction only in FC. Seed removal was also significantly lower (-33%) in FC compared to the ones registered in FB and FP. Ants represented 92% of all arthropods that visited the seed points in the three forest areas. The bigger seeds were the most removed ones, independently of its seed disperser adaptations and of the studied forest area. The results obtained suggest that forest logging can affect ant species composition, without affecting its diversity (except that of Pheidole). Reduced impact logging techniques have the capacity of preserving Pheidole species diversity, which guarantees seed movements similar to those of a primary forest. Nevertheless, conventional logging can reduce, both the number of species and occurrences of this genus, thus resulting in a reduced number of removed seeds. Such reduction probably jeopardizes forest regeneration after wood extraction.
Acesso aberto (Open Access)
Revisão taxonômica do grupo limata de Crematogaster Lund, 1831 (Formicidae: Myrmicinae: Crematogastrini)
(Universidade Federal do Pará, 2010) FELIZARDO, Sherlem Patricia de Seixas; HARADA, Ana Yoshi; http://lattes.cnpq.br/3315398997543458
The large number of species, peculiar morphology and its wide geographic distribution make the genus Crematogaster one of the most complex taxonomically among ants. About 780 species and subspecies were described and constants changes are made over time due to its morphological variety. A few revisions only for regional fauna were made for this genus. This study is a taxonomic revision of the species group Crematogaster limata. Six species are redescribed: Crematogaster brasiliensis Mayr, 1878, C. carinata Mayr, 1862, C. levior Longino, 2003, C. Limata Smith, 1858, C. longispina Emery, 1890, C. tenuicula Forel, 1904 and four new species are described: Crematogaster n. sp. 1, Crematogaster n. sp. 2, Crematogaster n. sp. 3, Crematogaster n. sp. 4. The taxa Crematogaster longispina var. boliviana was raised to species level and redescribed. Maps of the geographical distribution for it species and a key for species based in workers are presented.
Acesso aberto (Open Access)
A riqueza das formigas relacionada aos períodos sazonais em Caxiuanã durante os anos de 2006 e 2007
(2012-09) SANTOS, Sergio Rodrigo Quadros dos; VITORINO, Maria Isabel; HARADA, Ana Yoshi; SOUZA, Adriano Marlisom Leão de; SOUZA, Everaldo Barreiros de
The temporal variability of ant fauna collected in Caxiuanã -PA during the leaf litter ants protocol of the Project TEAM/Caxiuanã were studied based on the local meteorological conditions observed during the months from January to April (rainfall season), and July to October (dry season) to 2006 to 2007. Data from the micrometeorological tower at Caxiuanã were used. During the rainfall season the predominance of high values of precipitation and soil moisture and low values of air temperatures is noted. In the dry season the opposite behavior compared to the rainfall season is observed. In general, it was observed that the frequency of ants is greater when precipitation and soil moisture are reduced and air temperature is increased. Ants of the genera Crematogaster, Hypoponera, Pheidole and Solenopsis have higher number of individuals. It was noted also that the statistical correlations using second-order polynomial function, between atmospheric variables and the frequency of ants, occurred in reverse mode for precipitation and soil moisture, and direct for the air temperature. Our results corroboreted to the high abundance of the four upper mentioned ant genera in relation to the environmental atmospheric condictions in tropical regions.