Navegando por Assunto "Mato Grosso - Estado"

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Acesso aberto (Open Access)
Abundância e diversidade de palmeiras no Distrito Florestal Sustentável da rodovia BR-163, Pará, Brasil
(2011-09) SALM, Rodolfo Aureliano; JARDIM, Mário Augusto Gonçalves; ALBERNAZ, Ana Luisa Kerti Mangabeira
The abundance and diversity of palm species, as well as its relationship with forest structure were investigated in two study areas in the Sustainable Forest District of the BR-163 road. As such, forty parcels of 0.04 ha (20 × 20 m) were established in a pristine forest in the Amazonia National Park, and another forty parcels in a area submitted to timber logging in the Tapajos National Forest. In each parcel, all the trees with DBH ≥ 10 cm were measured and the adult palms were identified and counted. We verified that although the exploited forest of the Tapajos National Forest is structurally more open than the forest in the national park, it still has a quantity and diversity of palms inferior to the national park, probably due to the dispersal limitation of palms and the relatively recent logging activities. We concluded that exploitation potential of palms in native forests of the region is extremely limited by the natural scarcity of palms in native forests of economic potential, but could be amplified with the deliberate planting of useful species, with benefits for the natural dynamics of the forest.
Acesso aberto (Open Access)
Amazônicos e tecnológicos: os Suruís de Rondônia e suas articulações globais
(Universidade Federal do Pará, 2012-08-03) COSTA, Tamiles do Espírito Santo; AMARAL FILHO, Otacílio; http://lattes.cnpq.br/2605877670235703
This work aims to describe and analyze the experience of the indigenous community Paiter-Suruí, located between the states of Rondonia and Mato Grosso, which experiences a process of technological integration. From materials posted on the internet about the Suruí´s partnerships, specially the partnership formalized with Google, is done a study of the position change of the Amazonian Indians, historically relegated to a subordinated position, who, in this new technological scenario, gains voice and ability to interfere in their own narrative, in particular using the internet. The concepts of "to see" and "to look", "social capital" and an overview on the imaginary built about the Indians, intends to subsidize a brief phenomenological analysis supported by a field research, which aims to understand how the Suruís see subjectively the objective phenomena they experience. In addition, other discussions will be raised during the work, such as post-colonialism, the dialogue between tradition and modernity and hybridization of cultures.
Acesso aberto (Open Access)
Análise da área desmatada municipal na Amazônia brasileira no período 2000-2004: uma abordagem com modelos não lineares
(2010-09) OLIVEIRA JÚNIOR, José Nilo de; DINIZ, Marcelo Bentes; FERREIRA, Roberto Tatiwa; CASTELAR, Luiz Ivan de Melo; DINIZ, Márcia Jucá Teixeira
There is a great amount of asymmetry in the distribution of deforestation in the Brazilian Legal Amazon, particularly in the states of Mato Grosso, Pará and Rondônia, what it would be, in principle, associate with certain common characteristics of their productive activities such as cattle, timber cutting and, more recently, the expansion in the production of grains. However, it can be inquired if municipalities with similar economic characteristics can be grouped as clubs with respect to deforestation. The goal of this article was to test the club convergence hypothesis of deforested areas in the cities of the Legal Amazon in the period of 2000 to 2004. In order to reach the objectives considered, a threshold model based in Hansen (2000) was used. The empirical results corroborate the hypothesis, with respect to formation of four clubs of convergence.
Acesso aberto (Open Access)
Avaliação do potencial alelopático de substâncias isoladas em sementes de araticum (Annona crassiflora)
(2010-12) INOUE, Miriam Hiroko; SANTANA, Dilerson Goulart; VILHENA, Karyme do Socorro de Souza; SOUZA FILHO, Antonio Pedro da Silva; GUILHON, Giselle Maria Skelding Pinheiro; POSSAMAI, Ana Cássia Silva; SILVA, Luiz Everson da; DALLACORT, Rivanildo
This work aimed to identify substances and the allelopathic potential of steroidal glycosides, isolated from the seeds of Annona crassiflora. Isolation of steroidal glycosides was carried out with the separation of chemical components of ethyl acetate extract in a chromatographic column and identified by 1H NMR. Germination tests with Euphorbia heterophylla and Ipomoea grandifolia were carried out in BOD Germinator at 25ºC and 12 hr photoperiod, monitored for 10 days at concentrations of 0, 20, 40, 80 and 100 mg L-1 of the materials isolated. Using the same concentrations, experimental radicle and hypocotyl development was maintained at 25ºC with 24hr photoperiod for 10 days. After the ethyl acetate extract was submitted to fractioning, the presence of characteristic signs of steroids in the 1H NMR spectrum was verified, providing a mixture of stigmasterol and sitosterol glycoside. The results indicate that the substances stigmasterol and sitosterol did not inhibit germination and germination velocity index (SIG) of E. heterophylla and I. grandifolia. However, both substances affected radicle and hypocotyl development of E. heterophylla.
Acesso aberto (Open Access)
Baetidae (Insecta, Ephemeroptera) em córregos do cerrado matogrossense sob diferentes níveis de preservação ambiental
(2011-09) SOUZA, Hilton Marcelo de Lima; CABETTE, Helena Soares Ramos; JUEN, Leandro
The effect of different stream environmental preservation levels, in 1st to 4th orders, over the richness, abundance, similarity in the composition and the potential of Baetidae (Ephemeroptera) species as bioindicators were investigated in a Cerrado region located in the state of Mato Grosso, Brazil. A total of twenty species/morphospecies were catalogued from the 1752 samples of nymphs, resulting in a new record for two species in Brazil. Values of Habitat Integrity Index (HII) were categorized among damaged, modified, and preserved environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz & McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of basins and the use of indicator species.
Acesso aberto (Open Access)
Batólito Guaporeí: uma extensão do Complexo Granitoide Pensamiento em Mato Grosso, SW do Cráton Amazônico
(2013-03) NALON, Patrícia Alves; SOUSA, Maria Zélia Aguiar de; RUIZ, Amarildo Salina; MACAMBIRA, Moacir José Buenano
The Guaporeí Batholith is located in the Vila Bela da Santíssima Trindade region, at Mato Grosso State (Brazil), and crops out over 240 km2 along the NW direction. It is situated in the Paraguá Terrane, included in the Rondonian-San Ignacio Province, in the southwestern portion of the Amazonian Craton. The batholith is made up of monzogranite, with subordinate granodiorite, quartz monzonite and syenogranite, shows coarse porphyritic/porphyroclastic texture, is metamorphosed in the greenschist facies and mylonitized along shear zones. The biotite is the main primary mafic mineral, sometimes associated with amphibole. Geochemical data indicated high-potassium calc-alkaline and metaluminous to peraluminous character, probably generated in continental arc environment, and evolved by fractional crystallization associated to crustal assimilation. Two stages of deformation related to the evolution of San Ignacio compressional orogeny were identified and are characterized by stretching and lineation, and development of S1 and S2 foliations. Dating by single zircon Pb-evaporation method yields a crystallization age of 1,314 ± 3 Ma, whereas Sm-Nd whole rock isotope data indicate a TDM model age of ca. 1.7 Ga and a negative value for εNd (t = 1,3) of -14, suggesting crustal contribution in the magma genesis. The obtained data indicate similarities between these rocks and those of the Pensamiento Granitoid Complex, in the Bolivian counterpart, and put in evidence that the Guaporeí Batholith is an extension of this complex.
Acesso aberto (Open Access)
Boas práticas agrícolas: análise de viabilidade financeira em propriedades sojicultoras e pecuaristas do Nordeste Mato-Grossense
(Universidade Federal do Pará, 2010-06-22) CHIACCHIO, Jayne Isabel da Cunha Guimarães; ALMEIDA, Oriana Trindade de; http://lattes.cnpq.br/0325909843645279
According to data from PRODES / INPE (2008), from 1988 to 2008, 369,154 km ² were deforested in the Amazon, an annual average of 17,578 km ². This process has been driven primarily by expansion of cattle ranching and agriculture. Several policies have been created to reduce deforestation. And these are targeted, usually by command and control instruments. A recent innovation, however, has been the search for improvements in environmental quality in medium and large farms through the introduction of Good Agricultural Practice (GAP). Based on this, this paper aims to examine whether the introduction of BPA in medium and large soy farms and ranches located northeast of Mato Grosso represents a financially viable alternative. The survey was conducted in five municipalities located northeast of Mato Grosso, in the Xingu watershed: Água Boa, Canarana, Querência, Bom Jesus do Araguaia and São Félix do Araguaia. First, we collected detailed data from activities in the region of study. For that, 40 farmers were interviewed (20 soy farmers and 20 ranchers). The second step raised the cost data of adoption of good practices on 14 soy farms and ranches found in the Registry of Social-Environmental Responsibility (RSR) of the Aliança da Terra (AT)/Instituto de Pesquisa Ambiental da Amazônia (IPAM). For the analysis of financial viability of Good Practice, we used three instruments: simple return, net present value (NPV) and internal rate of return. The results showed that BPA is capable of implementation, but there is a financial loss for the producer when he chooses to adopt BPA. However, opportunities for gains from adoption of BPA (such as the receipt by REDD, increased productivity, increased selling prices, among others) can reduce these "losses" and equalize the gains to production without BPA.
Acesso aberto (Open Access)
Caça em assentamento rural no Sul da Floresta Amazônica
(Universidade Federal do Pará, 2004-05-07) TRINCA, Cristiano Trapé; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
In this study, 1 investigated the effects on the local populations of wild mammals of the hunting activities of the residents of a rural settlement in the Amazonian forest of the northern part of the Brazilian state of Mato Grosso. The second part of the Japuranã settlement — the study site — was occupied three years ago. Formal interviews were conducted with 17 settlers. Additional information was collected informally, during all forms of contact with settlers during the study period. The majority of settlers are from southern and southeastern Brazil. Typically, they are semi-literate rural workers, with very low monthly income. The principal hunting techniques used are "ambush", "chase with dogs" and "excursion". Game meat was an important part of settlers' diets, and was included in about a third of meals. The activities of 14 hunters were monitored between May and November, 2003, during which they captured 113 mammals belonging to 17 species. Analyses of population structure based on crania were possible for only two species, the white-lipped (Tayassu pecari and the collared (Pecari tajacu) peccaries. The analysis indicated that the situation of the structure of the population of the T.pecari and the P.tajacu is sensible and could seriously be affected if the pressure increase. An estimated 4096.3 kg of game was extracted from an area of approximately 38 km2, representing an average consumption of 0.268 kg of meat per person per day. Line transect population surveys were conducted at three sites, two in the settlement and a third in a nearby "control" area of continuous forest where hunting is not practised. Over a total transect of 108 km, 15 species of mammal and four species of bird were recorded, with relatively high sightings rates in comparison with most other sites in central and eastern Amazonia. However, species richness and abundance were greater at both settlement sites in comparison with the control. The abundance of ungulates (peccaries and deer), the primary game species, was also greater in the settlement (both sites) in comparison with the control. This suggests clearly that hunting pressure has not yet had a significant impact on the mammal populations of the settlement, at least in terms of abundance. The majority (85.8%) of hunting was directed at subsistence, while 8.0% involved the control of predators of domestic stock, and the remaining 6.2% was "predatory", basically for the protection of the dogs during chase hunting. Despite this pressure, the relative abundance of mammals in the settlement suggests that hunting is sustainable over the short term (three years), possibly as a result of the natural abundance of mammals in the region, and the still reduced human population density. However, this situation may not last long, given that deforestation and consequent habitat fragmentation is an ongoing process, and there are no controls on hunting in the area. The results of this study provide an important data base for the development of management plans for the local fauna, involving the local community, government, environmental organisations, and research institutions. These plans will be fundamental to both the conservation of species and the more efficient exploitation of game resources by local settlers.
Acesso aberto (Open Access)
Caracterização genética parcial e completa da nucleoproteína de hantavírus na Amazônia brasileira
(Universidade Federal do Pará, 2011) SIMITH, Darlene de Brito; NUNES, Márcio Roberto Teixeira; http://lattes.cnpq.br/0299116892743368
The Hantavirus Pulmonary Syndrome (HPS) has been diagnosed in the Brazilian Amazon since 1995. Until december 2010 have been diagnosed 289 cases in the Brazilian Amazon, registered in the states of Mato Grosso, Pará, Maranhão, Amazonas and Rondônia. The overall objective of this study was to characterize genetically hantavirus strains circulating in these states. Samples of viscera from wild rodents positive for IgG antibodies against hantavirus caught in ecoepidemiológicos studies, conducted in the municipalities of Itacoatiara/AM, Alto Paraíso/RO and Campo Novo do Parecis/MT, and serum/blood of human cases of HPS from the municipalities in the area of influence of BR-163 in the states of Pará and Mato Grosso, Tomé-Açu/PA, Tangará da Serra/MT, and viscera of a pool of death coming from Anajatuba/MA. The samples were extracted viral RNA, followed by the reactions of RT-Hemi-Nested-PCR for samples from rodents, RT-Nested-PCR for human samples and nucleotide sequencing using the Sanger method and pyrosequencing, and later, scanned for matters such as identity (BLAST search), similarity (Simplot) and nucleotide and aminoacidic homology with other hantaviruses (Clustal W). We obtained partial sequences of hantavirus in five species of rodents Oligoryzomys microtis (n=2 from Itacoatiara/AM; n=3 from Alto Paraíso/RO) and in eight samples from humans (n=1 from Tomé-Açu/PA; n=1 from Altamira/Cachoeira da Serra; n=1 from Novo Progresso/PA; n=1 from Guarantã do Norte/MT; n=1 de Anajatuba/MA and n=3 de Altamira/Castelo dos Sonhos). Using the strategy of pyrosequencing were obtained complete sequences of the gene N, S-RNA of three hantavirus in rodents (n=2 from Alto Paraíso/RO and n=1 from Campo Novo do Parecis/MT) and two human cases (n=1 from Tangará da Serra/MT and n=1 from Novo Progresso/PA). Analysis of complete sequences showed the presence of ORFs for possible NSs protein, as described for other hantaviruses. Phylogenetic analysis of the sequences obtained in this study and other hantaviruses available in GenBank suggests that the virus Castelo dos Sonhos is responsible for cases of HPS in municipalities in the area of influence of BR-163, obtaining for the first time, the complete sequence of this virus in rodent Oligoryzomys utiaritensis, coming from Mato Grosso; confirmed the continued circulation of Laguna Negra-like virus associated with HPS cases in the state of Mato Grosso; the Rio Mamoré-like virus was first time detected in O.microtis rodents, the state of Amazonas and Rondônia, but not associated with human cases; the virus Anajatuba was responsible for a case of death from Maranhão. This work will serve as support for future epidemiological and molecular studies, therefore, provides new data about the spread of hantaviruses in the Brazilian Amazon.
Acesso aberto (Open Access)
Comparando as consoantes das línguas Tapajúna e Suyá
(2011-12) RODRIGUES, Cíntia Karla Coelho; SILVA, Marília de Nazaré Ferreira
This study investigates historical and comparative aspects of Tapajúna (Jê family) consonantal features, comparing cognates between Tapajúna and Suyá (also of the Jê family) with the goal of specifying similarities and differences in an effort to describe the reconstruction of the Macro-Jê stock. The comparative method was applied to detect correspondences between the languages. Data from Tapajúna and Suyá were compared to Proto-Jê data, as reconstructed by Davis (1966). There are few differences between Tapajúna and Suyá. Where there are variations in identical phonetic-phonological contexts, the question of speaker age arises, since, for example, pre-nasalized consonants occur in the speech of young people, whereas older Tapajúna speakers use only nasalized consonants.
Acesso aberto (Open Access)
Composição e riqueza de espécies de anfíbios anuros em três diferentes habitat em um agrossistema no Cerrado do Brasil central
(2013-03) CAMPOS, Vitor Azarias; ODA, Fabrício Hiroiuki; JUEN, Leandro; BARTH, Adriane; DARTORA, Aline
Adaptive plasticity has been postulated as one of the integrating factors that explain the distribution and abundance of species on different habitat with different environmental variations. The environmental heterogeneity is the most important factor for the maintenance, increment or decrement of biodiversity. On this study we determined the effect of periodicity and habitat structure on the richness and composition of species of three different habitat: stream (P1), temporary ponds (P2) and permanent dam (P3) in an agrosystem in the Central Brazilian Cerrado. We performed nine excursions to the field during November 2005 to April 2007. We found and registered the species by direct search and vocalization orientation. We identified 19 anuran species belonging to four families: Bufonidae (one species), Hylidae (nine species), Leptodactylidae (five species), and Leiuperidae (four species). The greatest richness and abundance were recorded in temporary ponds (P2), which differed significantly from the stream (P1) and from the permanent dam (P3). Dendropsophus nanus, Hypsiboas raniceps and Leptodactylus chaquensis showed strong association with P2. P2 and P3 showed greater differentiation between themselves in species composition than when compared to P1. Despite the fact that the studied areas are surrounded by intense farming and present a high degree of anthropic disturbance, these areas showed a high species richness being an important refugee for the amphibians, although the species found on this work are usually associated to impacted areas or open phytophysiognomies and are favored with the creation of artificial environments such as those in this study.
Acesso aberto (Open Access)
Composição, ecologia e história natural das serpentes de uma região de transição Amazônia - Cerrado, Mato grosso, Brasil
(Universidade Federal do Pará, 2010) ABE, Pedro Santos; COSTA, Maria Cristina dos Santos; http://lattes.cnpq.br/1580962389416378
This study aimed to document the composition and natural history of a community of snakes recorded at Tanguro Farm, Querência municipality, State of Mato Grosso, Brazil, an area which represents a transition between two major neotropical biomes, Amazonia and Cerrado. Six expeditions to the study site were carried out, resulting in the record of 203 specimens (194 captures), distributed in 34 species, 26 genera and 8 families. An estimate based in the incidence of rare species (Jackknife 1) indicated a total richness of 38 species in the study site, which demonstrate that the inventory was relatively exhaustive. The most abundant species were Caudisona durissa (N=50), Philodryas olfersii (N=15), Philodryas nattereri (N=13), Xenodon rabdocephalus (N=12), Lachesis muta (N=10) e Liophis almadensis (N=10). A Principal Coordinates Analysis (PCO) demonstrated that the taxocenosis are superimposed, revealing a trend to formation of three distinct groups: Amazonia’s, Cerrado´s and Mata Atlantica´s taxocenosis. The species composition at Tanguro Farm was intermediary between the groups formed by Amazonian and Cerrado species, occurring species with wide distribution ranges as well as species restrict to either Amazonia or Cerrado. The pattern of habitat use of the studied taxocenosis is terrestrial, followed by semi-arboreous and fossorial. With regards to the feeding strategies, there are a predominance of generalist snake species. An analysis of ecological groupings showed four functional groups, suggesting that the taxocenosis complexity could be explained by ecological and historical factors.
Acesso aberto (Open Access)
A comunidade de Curculionidae (Coleoptera) de inflorescências da palmeira Euterpe longebracteata Barb. Rodr. em uma área de transição Amazônia-Cerrado, Mato Grosso, Brasil
(Universidade Federal do Pará, 2009-10-30) GUIMARÃES, José Raimundo Rocha; VALENTE, Roberta de Melo; http://lattes.cnpq.br/9638288458835324
The research was done with the community Curculionidae inflorescences of the palm Euterpe longebracteata in riparian areas (PPAs), degraded and preserved, in Tanguro Farm, Mato Grosso, Brazil, aiming to provide inputs on policy management and recovery areas. The weevils represented the most important component of the fauna associated with the inflorescences of the E. longebracteata, with 23 species richness, frequency of 97% in the samples and abundance of 10,000 (or 90% of total abundance). Species Phyllotrox sp. 18, Phyllotrox sp. 19, Erirhininae gen.n.Asp.1 , Erirhininae gen.n.Esp.1 and Bondariella sp. 3 accounted for more than 98% of abundance, were found to be dominant in the inflorescences of E. longebracteata and therefore specifically related to the palm and can act as effective pollinators species of the E. longebracteata in the area. Despite the differences between PPAs preserved and degraded populations of E. longebracteata and species composition of Curculionidae were not correlated with the level of degradation of PPAs. The wealth of Curculionidae also not correlated with canopy cover, distance to the edge of the sample, size of inflorescences and number of flowers per inflorescence of E. longebracteata. The influence of collection period on the abundance of most dominant species was regarded as indicative of population dynamics and ecological succession. While Phyllotrox sp. 19, seems to present a pattern of aggregate distribution. Species Phyllotrox sp.18 and Erirhininae gen. No The sp. 1 were considered as having plenty more sensitive to degradation of PPAs. The palm E. longebracteata has potential use in the recovery of degraded areas of Tanguro farm because their populations and species of Curculionidae likely pollinators showed tolerance to the observed degradation.
Acesso aberto (Open Access)
Depósitos carbonáticos de Tangará da Serra (MT): uma nova ocorrência de capa carbonática neoproterozóica no sul do Cráton Amazônico
(2008-12) SOARES, Joelson Lima; NOGUEIRA, Afonso César Rodrigues
Cap carbonates are exceptional deposits related to the end of Neoproterozoic low-latitude glaciations. In the Tangará da Serra region, south Amazon craton, was described a Neoproterozoic carbonatic succession with approximately 20 m thick that includes the upper part of the Mirassol d'Oeste Formation and the base of the Guia Formation, respectively the dolomitic and calcareous caps of basal Araras Group. The cap dolomite is composed of pinkish peloidal dolograinstones with planar to low angle truncated laminations interpreted as deposits of a shallow to moderately deep platform. The cap limestone consists in massive to laminated siltstone and megaripple bedded crystalline limestone interpreted as deposits of moderately deep wave dominated mixed platform. Rippled crystalline limestone with crystals fans (pseudomorphosed aragonite) interbedded with shales were interpreted as oversaturated-CaCO3 deep platform deposits. Limestone with slump structures, convolute bedding and sinsedimentary faults characterize deposits of slope and neptunians dykes, filled by calcareous breccias, and isolated deformed limestone beds suggest seismic activity during the sedimentation. The succession of Tangará da Serra extends the occurrence of cap carbonates in the southern Amazon craton and corroborate with the presence of a large carbonate to mixed platform formed during the transgression after the glaciation Puga, correlate to Marinoan event.
Acesso aberto (Open Access)
Depósitos flúvio-costeiros da Formação Raizama, Ediacarano-Cambriano da faixa Paraguai Norte, região de Nobres, Mato Grosso, Brasil
(2014-12) SANTOS, Hudson Pereira; SILVA JÚNIOR, José Bandeira Cavalcante da; NOGUEIRA, Afonso César Rodrigues; ABRANTES JÚNIOR, Francisco Romério
The Ediacaran-Cambrian Raizama Formation presents siliciclastic deposits exposed discontinuously along of the southern margin of the Amazon Craton and the Northern Paraguay Belt, Central-Western Brazil. These deposits are interpreted as progradational coastal succession conformably overling the carbonate platform succession of the Upper Araras Group. The facies and stratigraphic analysis of outcrop section were carried out in the Nobres region, State of Mato Grosso, allowed the individualization of seventeen facies, grouped into five facies associations (FA): FA1) lower shoreface, consisting of sandstone with parallel and wave-truncated lamination (microhummocky) parted by laminated mudstones, locally bioturbed by Skolithos; FA2) upper shoreface, composed by parallel and swaley cross bedded sandstone; FA3) subtidal, represented by sandstones with tangential and through cross stratifications drapped by siltstone/very fine sandstone laminae interpreted as channel and bar deposits; FA4) tidal flat is characterized by sandstones with tangential and sigmoidal cross bedding, even parallel stratification, low-angle cross bedding, mud cracks, siltstone/very fine sandstone rhythmites with flaser bedding, organized in shallowing-meter scale cycles; and FA5) distal braid plain consisting of sandstones with through cross-bedding and laterally discontinuous lags, parallel stratification and low-angle cross stratification partially reworked by wave. The sedimentation of the Raizama Formation suggests an increase in the siliciclastic supply linked to uplift regions of the Craton in the northwest of the studied area, succeeding the Araras carbonate platform deposits. Tubular trace fossils in the FA1 indicate, by the first time, the presence of burrowed organisms, what strongly points to an age near of the Ediacaran-Cambrian boundary.
Acesso aberto (Open Access)
Efeito do uso do hábitat sobre a comunidade de Gerromorpha (Heteroptera) em uma área de transição Amazônia-cerrado, Mato Grosso, Brasil
(Universidade Federal do Pará, 2008) WANZELER, Elaine Cristina de Miranda; FERNANDES, José Antônio Marin; http://lattes.cnpq.br/6743352818723245
The aquatic and semiaquatic bugs (Heteroptera) belong to three different monophyletic infra-orders: Gerromorpha, Nepomorpha and Leptopodomorpha. In Brazil only a few studies on these groups have been carried out, mostly in the state of Minas Gerais. This study aimed to determine land use intensity effect over the aquatic Heteroptera-Gerromorpha community. The study was carried out at Tanguro farm, state of Mato Grosso, in a area of transition between cerrado and tropical rain forest. Samples were collected on May and July in 2006 and 2007 in six streams within three different environments: soybean plantation, pasture and forest. Five families, 19 genera, 36 species and 13 morphospecies of Gerromorpha were collected. Species accumulation curves for each environment did not reach an asymptote, though they showed a clear tendency to stabilization. Therefore, increasing the number of samples probably will set the real species number close to the observed for the whole study area. Although vegetation coverage was significantly different among the three environments (ANOVA, F2,45= 23,72; P < 0,001), the habitat type did not influence the number of Gerromorpha species (ANOVA F3,44= 0,77; P = 0,52). In addition, the two axis of a MDS analysis based on species composition did not discriminate the habitats. On the other hand, the abundance of seven species was significantly different among habitats. Analysis of the abundance matrix shown (axis 1- MANOVA; F2,45 = 16,27; P < 0,001 and axis 2- MANOVA; F2,45 = 6,31; P = 0,004) segregated forest species. The three habitats shared 57,14% of the species collected. The considerable decrease in number of specimens from the forest to the pasture may be related to the lost of vegetation coverage in disturbed areas. The species Brachymetra lata, Brachymetra sp. 1, Cylindrostethus palmaris, Tachygerris celocis, Rhagovelia paulana, Rhagovelia whitei and Neogerris lubricus could be considered indicator species based on significant differences in abundance between disturbed and undisturbed areas.
Acesso aberto (Open Access)
Efeitos do fogo recorrente na serrapilheira: consequências para artrópodes, decomposição e mineralização de carbono e nitrogênio em uma floresta de transição da Amazônia
(Universidade Federal do Pará, 2008) SILVEIRA, Juliana Miranda da; MOUTINHO, Paulo Roberto de Souza; http://lattes.cnpq.br/7277077476036269
Arthropods play an important role in ecosystem functioning, participating in nutrient cycling, decomposition and the breaking up and mixing of the leaf litter. Forest fires are increasing across the Amazon basin, and destroy the litter layer and kill the invertebrates that live within it. The objective of this thesis is to investigate how recurrent fires affect these processes, investigating the abundance and density of leaf-litter arthropods and the rate of decomposition of organic material and the mineralization of C and N, in a transitional Amazonian forest in the municipality of Querencia in the state of Mato Grosso, Brazil. The study was conducted in 50 ha of primary forest (500 x 1000 m) that was experimentally burned every year from 2004, and an unburned primary forest control of the same size. The arthropods were collected in 40 pitfall traps and 40 funnel Berlese traps, located randomly. The collections were undertaken in February, April (wet season), June, and August (dry season) of 2007, after the third experimental burning. The arthropods were identified to the level of Order, and the ants were identified to the level of Genera. The decomposition study was undertaken using 480 litter bags, randomly distributed with 240 in each plot, 4 months after the last burns. The litter bags were constructed with 2 mm nylon mesh (fine mesh), and 50% of them had 1 cm² holes cut in their sides (coarse mesh). 10g of dry leaves were placed in each litter bag, and 30 bags were collected from each plot every 2 months, equalling 2 collections in the wet season and 2 in the dry season. The litter bags were dried in an oven, and litter was weighted again to calculate decomposition. The difference between inicial and final weight showed the decomposition rate. Ten litter bags were selected randomly from every collection, mesh size, and plot, and subjected to a C and N analysis. The arthropods demonstrated strong seasonal differences. Springtails were less abundant and ants were more abundant in the dry season. Along with the seasonal effects, arthropods had diverse effects to the recurrent fires: Orthoptera were always more abundant in the burned plots in all post-fire samples when compared to controle plot. In general, macro-predators (ants, beetles, and others) were more abundant in the burned forest, while the ecosystem engineers and decomposers (cockroaches, Acaridae, and others) were less abundant in the burned forest, when compared to control plot. Ants were more diverse in the dry season, and also showed strong seasonal differences in composition. There was also a marked difference in ant diversity between the two plots, and fires favoured generalists ants. The decomposition rate in the burned forest were lower than in the control, and the fine mesh litter bags had a lower rate of decomposition than those with holes cut in their sides (coarse mesh). The level of C and N was also different between the plots, and the C/N ratio (indicating microbial activity) was stable over time in all post-fire collections, while the C/N ratio in the control plot declined gradually during the 4 collections. These results indicate that fire modifies the leaf-litter fauna, affecting the abundance and composition of various taxonomic groups. The fine mesh litter bags indicate that the exclusion of macroarthropods reduces the rate of organic matter decomposition and that microarthropods are more affected by fires. Fire also reduces the mineralization of C e N as C/N was stable in burned plot. Overall, this study shows that recurrent fires have strongly effects on leaf-litter fauna and nutrient cycling in Amazonian transitional forests.
Acesso aberto (Open Access)
Effects of environmental factors on community structure of Leptophlebiidae (Insecta, Ephemeroptera) in Cerrado streams, Brazil
(2013-09) BRASIL, Leandro Schlemmer; SHIMANO, Yulie; BATISTA, Joana Darc; CABETTE, Helena Soares Ramos
We analyzed the effects of environmental factors on abundance, species richness, and functional group richness of Leptophlebiidae in 16 sampling points along four Cerrado streams. Across three periods of 2005, we collected 5,492 larvae from 14 species in stream bed substrate. These species belong to three functional feeding groups: scrapers, filtering collectors and shredders. The abundance and species richness were not affected by water quality, but habitat quality related to presence of riparian vegetation had positive effects on the abundance of shredders. Our results add important information on the natural history of the species and functional groups of aquatic insects and also provide relevant data for the monitoring and conservation of streams in the Brazilian Cerrado.
Acesso aberto (Open Access)
Estrutura e composição da comunidade de Trichoptera (Insecta) de rios e áreas alagadas da bacia do rio Suiá-Miçú, Mato Grosso, Brasil
(2011-09) NOGUEIRA, Denis Silva; CABETTE, Helena Soares Ramos; JUEN, Leandro
The composition, abundance and species diversity of Trichoptera immatures was studied in 12 tributaries of Suiá-Miçú River Basin, a mosaic of wetlands, streams and rivers tributary of the Xingu River in the Cerrado-Amazonian Forest transition zone in Mato Grosso, Brazil. The varying sizes, flow types and conservation levels of the tributaries were sampled through three periods between 2007 and 2008 by the use of fixed transects along the environments margins. A total of 867 larvae was collected (divided in seven families, 17 genera, 49 species/morphospecies) with the most abundant and rich families being Hydropsychidae and Leptoceridae and the most abundant species Leptonema sparsum (n = 370). There has been loss of species richness in impacted, large and lentic environments. Composition variations related to the flow, the vegetation type and the interaction between conservation levels and flow was detected. Conservation levels, width and the quantitative habitat integrity index (HII) did not influence the Trichoptera composition. These results may encourage further investigation of impact effects on aquatic insect compositions and pattern of distribution in the transition area between the Cerrado and the Amazonian Forest.
Acesso aberto (Open Access)
Estudo da comunidade de pequenos mamíferos não-voadores, sob efeito do fogo e da borda, em área de floresta de transição Amazônia-Cerrado, Querência, MT
(Universidade Federal do Pará, 2008-10-10) SANTOS, Paulo Guilherme Pinheiro dos; OLIVEIRA, Ana Cristina Mendes de; http://lattes.cnpq.br/1199691414821581
The deforestation of the Amazon, caused by farming and agribusiness activities in the northern state of Mato Grosso, has committed Transition Forests Amazon-Savanna, before the biodiversity of these areas is known by researchers. The fauna of small non-flying mammals is part of the little-known groups in the region, and may be suffering impacts of human activities, primarily effect of fire, used for cleaning of pastures and deforestation for the soybean plantations. This study characterized the diversity of small mammals not flying in an area of Amazon forest-savannah transition in the northern state of Mato Grosso and investigated the effect of fire and the effect of edge on this group of fauna. Two areas of 150 hectares were sampled, a preserved and another under impact of fire, with 183 traps of the type live-trap for three years in two season (dry and rainy seasons). The method used was the capture-mark-recapture. The sampling effort was 23,424-traps night. 390 individuals were captured with a successfully capture of 1.66%. A total of 11 species were caught, 6 rodents and 5 marsupials. Hylaeamys megacephalus was the most abundant species. The diversity of small mammals in the study area was more related to the Savanna than Amazon. In relation to fire, the species richness was not statistically different, but the abundance was significantly higher in transects located in an area without fire. Two distinct groups of transects were characteristic depending on the presence or absence of fire based on the composition of small mammals. The abundance of Hylaeamys megacephalus was significantly higher in transects that suffered no impact from fire. Regarding the effect of edge in Area 2, despite the richness of species was not significantly different, the abundance was significantly higher regarding distance from the border. Already in Area 1, nor richness nor abundance was statistically different regarding distance from the edge. This fact could be masked by both the direct and indirect effect of experimental fire on small mammals. When considered together fire and distance from the border, the relationship between them became clearer, since all transects sampled under effect of the fire had minor abundances. The population size of Hylaemys megacephalus was calculated over five seasons (dry and wet) in the area without influence of fire, and the rainy season of 2006 was statistically different peak and the other that growth can be explained by the “Alle effect”. There was no statistically significant differences in the structure of the community of small non-flying mammals between the dry and rainy seasons. This work contributed to the search of mammal knowledge at this region threatened by human pressures.