DSpace Coleção: Artigos Publicados em Periódicos
https://repositorio.museu-goeldi.br/handle/mgoeldi/56
Artigos Publicados em Periódicos2024-01-27T23:49:59ZEcologia reprodutiva dos tralhotos Anableps anableps e Anableps microlepis (Pisces: Osteichthyes: Cyprinodontiformes: Anablepidae) no rio Paracauari, ilha de Marajó, Pará, Brasil
https://repositorio.museu-goeldi.br/handle/mgoeldi/1470
Título: Ecologia reprodutiva dos tralhotos Anableps anableps e Anableps microlepis (Pisces: Osteichthyes: Cyprinodontiformes: Anablepidae) no rio Paracauari, ilha de Marajó, Pará, Brasil
Abstract: and A. microlepis collected from the Paracauari River between 48º 30’ 20” W/ 00º 44’ 36” S and 48o 31’ 12” W/ 00o 43’ 34” S Marajó Island, state of Pará, Brazil, from August 2001 through April 2002. Sampling was carried out with trawls, shrimp nets, and casting-nets. A total of 1.203 specimens were collected and analyzed, from which 901 were A. anableps and 302 A. microlepis. Both species group themselves into schools of ten to 50 individuals; however, A. microlepis is predominant in the summer when the water is more saline, while A. anableps predominates in the winter when the water is fresh. Regarding sex ratio, it was of 1:1 for A. anableps, while A. microlepis females surpassed males in a ratio of 2:1. In relation to size, A. anableps (x = 240 mm) is on average smaller than A. microlepis (x = 270 mm), but females of each species were significantly larger than the males. Both species reproduce throughout the year, yet with reproductive peaks in distinct periods: A. anableps in winter and A. microlepis in summer. Each female produces ten to 31 oocytes that are released into the ovarian cavity when they reach 1.0-1.5 mm in diameter; when reaching 2.0 mm they attach themselves once again to the ovary’s wall, where they remain until eclosion. The embryos are released inside the ovarian cavity when development is complete and measure 45-47 mm in length at birth. Despite being mixed, each species maintains distinct strategies regarding structural and temporal organization time, and requiring different environmental conditions – possibly those that are more favorable for offspring development.
Tipo: Artigo de Periódico2008-09-01T00:00:00ZDinâmica da regeneração natural de árvores em áreas mineradas na Amazônia
https://repositorio.museu-goeldi.br/handle/mgoeldi/1460
Título: Dinâmica da regeneração natural de árvores em áreas mineradas na Amazônia
Abstract: Forest restoration on strip mines is done with many native species in an effort to enrich floral composition and accelerate soil protection, along with the replacement of top soil and its contained seed bank. The aims of this study are to analyze the dynamics and structure of natural tree regeneration, identify the trees’ seeds and their dispersers, elaborate a set of indicators for the dynamics of tree regeneration, and to rank reforested areas on a year by year basis at the Mineração Rio do Norte bauxite strip mine in the Saracá-Taqüera National Forest in Porto Trombetas, Pará state, northern Brazil. The study is based on the results of monitoring 26 permanent forest plots over four years (2001-2005) in areas reforested by the mining company between 1981-1987 and 1992-1996. All trees over 1,5 m in height were sampled. Of the observed tree regeneration, it is possible to conclude the following: (i) more tree species are found in younger areas (9-13 years of reforesting) than in older ones (18-24 years); (ii) the oldest areas show the largest annual increase in number of tree species; (iii) tree abundance (individuals per ha) tend to be greater in younger areas; (iv) the annual recruitment ratetends to be higher in older areas than in younger ones; (vi) annual mortality rates are greater in younger areas than in older ones; (vii) the annual turnover rate is much greater in older areas; (viii) turnover time is greater in younger areas; (ix) medium tree diameter was practically constant during the monitoring period; (x) the annual increase in basal area is greater in older areas than in young ones; (xi) the median total height is greater in younger areas than in older ones; (xii) many tree species are dispersed by more than one agent and more than 80% of the monitored tree species are dispersed by animals whose role in ecological succession is fundamental; (xiii) the plots reseeded in 1992 are ranked as having the best forest regeneration, whereas those from 1987, on the other extreme, exhibit the most problems; (xiv) research on top soil management is needed in areas strongly impacted by human activities that are to be reforested; (xv) forestry practices and soil preparation should also be refined in order to accomplish efficient forest restoration where the objective is to maximize tree diversity and biomass, especially of well-adapted, fast-growing native species
Tipo: Artigo de Periódico2007-05-01T00:00:00ZRelações da biomassa microbiana do solo com características químicas de frações orgânicas e minerais do solo após exploração mineral na Amazônia Oriental
https://repositorio.museu-goeldi.br/handle/mgoeldi/1456
Título: Relações da biomassa microbiana do solo com características químicas de frações orgânicas e minerais do solo após exploração mineral na Amazônia Oriental
Abstract: The studied area is located in Porto Trombetas, district of Oriximiná, in the northwest of Pará, state, Brazil and has been subject to bauxite mining. The chemical and biological measurements were made on sites recuperation from 1981 to 1994, and one in Yellow Latosol under secondary forest, taken as reference. The values corresponding to the chemical and biological characteristics were obtained from analyses of the litter layer, light organic matter and soil of the altered and unaltered sites. The data were analyzed using Pearson correlation and Path Analysis. The results given how the chemical an biological composition litter layer and light organic matter were related of the carbon and microbialbiomass phosphorus concentration
Tipo: Artigo de Periódico2006-05-01T00:00:00ZCaracterização dos Argissolos amarelos com adição de resíduos de madeira: uma alternativa de uso como cobertura em solos da Amazônia paraense.
https://repositorio.museu-goeldi.br/handle/mgoeldi/1441
Título: Caracterização dos Argissolos amarelos com adição de resíduos de madeira: uma alternativa de uso como cobertura em solos da Amazônia paraense.
Abstract: In soils highly intemperic happens in the tropics, the reason of impoverishment is related to the lixiviation of the nutrients of the superficial layers. An alternative to minimize this loss of nutrients would be the use of organic coverings in these soils, be covering green or dead (mulch). In that sense, with the intention of characterizing the morphologic aspects, physical and chemical of the soils with and without addition of wood residues as covering, under the paricá (Schizolobium amazonicum) and pupunha culture (Bactris gasipaes). Were selected and collected 32 samples of 4 profiles of soil of the areas of paricá and pupunha planting with and without addition of wood residues for evaluation of their morphologic characteristics, physics and chemistries. The use of wood residues as covering favored for decrease of the density with values among 1,19 to 1,33 kg.dm-3 for the soils with addition of residues, while the soils without addition of wood residues the values were from 1,19 to 1,67 kg.dm-3. The same influence can be noticed for the increase of the porosity in the soils with material addition with values from 0,48 to 0,46 m3.m-3 in the superficial horizons, while the soils without residues, these demonstrated results from 0,35 to 0,38 m3.m-3. The pH values in water, for the soils with covering of wood residues varied from 4,6 to 6,0. To the soils without addition of wood residues, these presented values from 4,6 to 5,2. Could be verified that the addition of wood residues favored in the increase of the pH in the soil. The highest values for the saturation of bases were also observed for the soils with use of wood residues as covering, the values varied inside of these profiles, among 26 to 54%. While that for the profiles without addition of organic material presented variation among 26 to 39%. The appropriate use of wood residues in the soil played important part in the readiness of some nutritious as the calcium and the magnesium, reduced the acidity of the soils. Like this, the use of wood residues as covering in the soil in agroforests systems is satisfactory for allowing an appropriate destination for these materials besides improving the environmental conditions of the Amazon soils.
Tipo: Artigo de Periódico2006-01-01T00:00:00Z