6 research outputs found

    FORMAS DE HUMUS EM ECOSSISTEMAS DE FLORESTA COSTEIRA INTERTROPICAL. 1- A MATA ATLANTICA DE TABULEIROS

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    The Mata Atlantica ecosystems, located in the north part of Espirito Santo (Linhares) has two humus foons according to the forest type: Mata Alta Forest and Mussununga Forest. In the first case, humus is a mull-like fonn, and in the second, a moder-like humus is present. In the moder humus, 22t/ha corresponding to holorganic horizons- are superposed ou the A horizon, with 500kg/ha of organic nitrogen, while in the mull, this quantity reaches 6t/ha, with 100kg/ha of organic nitrogen. Below-ground pools -A horizon at 0-10cm depth- are similar in the two decomposition systems (10t/ha of organic carbon and700kg/ha of total nitrogen). A marked organic matter accumulation in Mussunnnga forest is essentially linked to the parental soil substrata with a limited clay fraction and very poor nutrieut content. Despite the factors detennining the humus fonns, which are simihlr to temperate forests, Mata Atlântica humus are differentiated by faster recycling of nutrieuts and a high organic-maner turnover.O ecossistema de Mata Atlantica localizado no norte do Espírito Santo (Linhares), apresenta duas fomas de húmus, de acordo com o tipo florestal: Mata Alta e Mata Mussununga. No primeiro caso, observa-se um húmus do tipo mull, enquanto a segunda fitofisionomia apresenta um humus do tipo moder. Nesta forma de humus, encontramos no horizonte holorgânico 22t/ha de matéria orgânica superficial e 500kg/ha de nitrogênio orgânico, enquanto no mull, estes valores alcançam 6t/ha de matéria orgânica superficial e 100kg/ha de nitrogênio orgânico. Com relação ao horizonte A subjacente (0-10cm), as duas áreas são similares nos seus conteúdos de matéria orgânica nitrogênio (10t/ha de carbono orgânico e 700kg/ha de nitrogênio total). Uma marcada acumulação superficial de matéria orgânica na Mata de Mussununga está intimamente relacionada à composição do substrato parental, com uma limitada fração de argila e baixíssimo conteúdo de nutrientes. Apesar dos fatores determinantes das formas húmicas serem semelhantes aos das florestas temperadas, os húmus da Mata Atlântica são diferenciados pela rápida reciclagem de nutrientes e alto" turnover" da matéria orgânica

    Evaluation of soil conditions in fast-growing plantations of Eucalyptus grandis and Acacia mangium in Brazil: A contribution to the study of sustainable land use

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    This study is a comparison of the holorganic horizons (L and F) and hemiorganic horizons (A11 and A12) of 7-years-old stands of Eucalyptus grandis and Acacia mangium, in the region of the Tabuleiro Forest, in Linhares, Espírito Santo, Brazil. In the soil under A. mangium, the stocks of organic matter in the L and F horizons were higher, and the C/N ratio was lower, due to the high nitrogen content of the leaf material. The same was observed for the A horizon chemical properties: the C and nutrients concentrations of the soil fine fraction were higher under A. mangium. The comparison of the C and nutrient concentrations between the A11 and A12 horizons and between the aggregate fraction and fine fraction showed similar trends in both sites. In both plantations, the C and nutrient concentrations were higher in A11 than in A12 horizons, and the soil aggregate fraction had higher concentration of nutrients than the soil fine fraction. Nevertheless, the percentage of aggregates in the soil matrix was much higher in A. mangium than in E. grandis. These results show that in this superficially sandy soil (Argissolo Amarelo Distrófico - Ultisol), the organic matter is the most important way of keeping nutrients, and that the aggregate fraction can be the most effective way of avoiding nutrient loss to the deeper soil horizons. In this context, A. mangium provides better conditions for restoring the soil fertility and soil biodiversity, thus providing better sustainability of the cropping systems than E. grandis. © 2004 Elsevier B.V. All rights reserved

    Neotropical xenarthrans: a dataset of occurrence of xenarthran species in the Neotropics.

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    International audienceXenarthrans—anteaters, sloths, and armadillos—have essential functions forecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosys-tem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts withdomestic dogs, these species have been threatened locally, regionally, or even across their fulldistribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths.Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae(3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data onDasypus pilo-sus(Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized,but new genetic studies have revealed that the group is represented by seven species. In thisdata paper, we compiled a total of 42,528 records of 31 species, represented by occurrence andquantitative data, totaling 24,847 unique georeferenced records. The geographic range is fromthe southern United States, Mexico, and Caribbean countries at the northern portion of theNeotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regardinganteaters,Myrmecophaga tridactylahas the most records (n=5,941), andCyclopessp. havethe fewest (n=240). The armadillo species with the most data isDasypus novemcinctus(n=11,588), and the fewest data are recorded forCalyptophractus retusus(n=33). Withregard to sloth species,Bradypus variegatushas the most records (n=962), andBradypus pyg-maeushas the fewest (n=12). Our main objective with Neotropical Xenarthrans is to makeoccurrence and quantitative data available to facilitate more ecological research, particularly ifwe integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, andNeotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure,habitat loss, fragmentation effects, species invasion, and climate change effects will be possiblewith the Neotropical Xenarthrans data set. Please cite this data paper when using its data inpublications. We also request that researchers and teachers inform us of how they are usingthese data

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data
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