13 research outputs found

    Pedotransference functions for prediction of density in soils of Piauí, Brazil / Funções de pedotransferência para predição da densidade em solos do Piauí, Brasil

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    The determination of the density of the horizons of a soil profile allows to evaluate certain properties, such as: porosity, hydraulic conductivity and water storage. However, measured data is not always available or easy to obtain. Thus, it was objective with the work to build and evaluate models of pedotransference function based on multiparameters of the soil as alternatives for the estimation of soil density in areas with agricultural potential of the state of Piauí. Thus, soil samples were collected from 42 soil profiles in the state of Piauí at depths of 0.0-0.20; 0.20-0.40; and 0.40-0.60 m e, characterized in terms of chemical and physical attributes. Through multiple regression analysis, two pedotransfer function models were generated: i) including all determined attributes and, ii) only the particle size analysis and total organic carbon. For both models, all classes (generalized character) were considered, as well as each individual soil class Latossolo (Ferralsol), Argissolo (Acrisol), Plintossolo (Plinthosol) and Neossolo (Arenosol). The generated pedotransference functions are alternative to estimate bulk density of soil, obtaining "excellent" performance in model I for the "Latossolos" (Ferralsols) and "Argissolos" (Acrisols), which included a greater number of variables in the construction of the predictive model of bulk density

    Estoque de carbono de um neossolo quartzarênico sob diferentes usos: Carbon stock in a quartzarenic neosol under different land uses

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    A transformação de ambientes naturais em ambientes de produção, somada ao manejo inadequado, pode comprometer significativamente as funções do solo, com perda da qualidade física, química e biológica, além de influenciar na dinâmica de entrada e saída de matéria orgânica do solo. Os Neossolos Quartzarênicos embora sejam considerados como de baixa aptidão agrícola, a uma demanda por novas áreas para o cultivo agrícola e o uso contínuo desses solos, com culturas anuais, pode acarretar rápida degradação, porém o manejo correto pode elevar o seu potencial produtivo em curto prazo. Nesse sentido o objetivo deste trabalho foi avaliar o efeito de diferentes usos do solo sobre o estoque de carbono de um Neossolo Quartzarênico no município de Codó no Estado do Maranhão. Amostras de solo foram coletadas em quatro perfis distintos, sendo em área de vegetação natural, pastagem de sequeiro, pastagem irrigada e cultivada com culturas anuais. Foram coletadas amostras com estrutura deformada e indeformada, nas profundidades de: 0 a 20 e 20 a 40 cm, em minitrincheiras, com cinco repetições. Os atributos do solo determinados foram: análise granulométrica (teor de argila, silte e total de areia), potencial hidrogeniônico, teor de carbono orgânico total e densidade do solo. Os dados foram submetidos à análise estatística descritiva, análises de correlação de Pearson e análise de variância e aplicou-se o teste de Tukey (5%). O teor de carbono orgânico total variou entre 0,8 e 1,5 dag kg com média de 1,2 dag kg. As maiores correlações para o teor de carbono orgânico total foram observadas com o silte (-0,65), com o total de areia (0,63) e com teor de argila (0,51). O maior teor de carbono orgânico total foi observado em área de vegetação de natural e a menor foi para a área cultivada com culturas anuais. Foi observado uma redução do teor de carbono orgânico total nas profundidades de 20 a 40 cm em todas as áreas. O estoque de carbono orgânico e o carbono orgânico foram alterados pelos diversos usos do solo

    Characterization, agricultural potential, and perspectives for the management of light soils in Brazil

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    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

    NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

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    Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

    NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

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    Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data

    Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

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    Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

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