7 research outputs found

    Classification of the coefficients of variation for sugarcane crops

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    The objective of this paper was to evaluate the range of classification of variation coefficient in experiments with sugarcane. For this study, some of the variables that are mostly used by researchers of the culture were considered. The data was obtained after extensive bibliographical revision from scientific journals, data base from the improvement program of sugarcane from the Federal University of Viçosa, master dissertations, doctorate thesis and technical reports. Classification ranges were proposed according to the Costa method, in which is based the use of a median and pseudo-sigma. The variables tons of stalks per hectare and tons of pol per hectare presented the highest ranges of the classification of the coefficients of variation, while the variable percentage of sucrose presented the lowest range. All of the variables presented specific ranges of classification, showing the need to consider, in the classification of coefficients of variation, the nature of the variable being studied.O objetivo deste trabalho foi avaliar a faixa de classificação do coeficiente de variação em experimentos com cana de açúcar. Para este estudo, foram consideradas algumas das variáveis mais utilizadas por pesquisadores da cultura. Os dados foram obtidos de extensa revisão bibliográfica em revistas científicas, banco de dados do programa de melhoramento de cana de açúcar da Universidade Federal de Viçosa, dissertações de mestrado, teses de doutorado e relatórios técnicos. Foram propostas faixas de classificação segundo o método de Costa, o qual se baseia no uso da mediana e do pseudo-sigma. As variáveis toneladas de colmos e toneladas de sacarose por hectare apresentaram as maiores faixas de classificação dos coeficientes de variação, enquanto que a variável porcentagem de sacarose apresentou a menor faixa dos coeficientes de classificação. Todas as variáveis apresentaram faixas de classificação específica, evidenciando a necessidade de se considerar, na classificação dos coeficientes de variação, a natureza da variável estudada

    Classification of the coefficients of variation for sugarcane crops Classificação dos coeficientes de variação para a cultura da cana de açúcar

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    The objective of this paper was to evaluate the range of classification of variation coefficient in experiments with sugarcane. For this study, some of the variables that are mostly used by researchers of the culture were considered. The data was obtained after extensive bibliographical revision from scientific journals, data base from the improvement program of sugarcane from the Federal University of Viçosa, master dissertations, doctorate thesis and technical reports. Classification ranges were proposed according to the Costa method, in which is based the use of a median and pseudo-sigma. The variables tons of stalks per hectare and tons of pol per hectare presented the highest ranges of the classification of the coefficients of variation, while the variable percentage of sucrose presented the lowest range. All of the variables presented specific ranges of classification, showing the need to consider, in the classification of coefficients of variation, the nature of the variable being studied.O objetivo deste trabalho foi avaliar a faixa de classificação do coeficiente de variação em experimentos com cana de açúcar. Para este estudo, foram consideradas algumas das variáveis mais utilizadas por pesquisadores da cultura. Os dados foram obtidos de extensa revisão bibliográfica em revistas científicas, banco de dados do programa de melhoramento de cana de açúcar da Universidade Federal de Viçosa, dissertações de mestrado, teses de doutorado e relatórios técnicos. Foram propostas faixas de classificação segundo o método de Costa, o qual se baseia no uso da mediana e do pseudo-sigma. As variáveis toneladas de colmos e toneladas de sacarose por hectare apresentaram as maiores faixas de classificação dos coeficientes de variação, enquanto que a variável porcentagem de sacarose apresentou a menor faixa dos coeficientes de classificação. Todas as variáveis apresentaram faixas de classificação específica, evidenciando a necessidade de se considerar, na classificação dos coeficientes de variação, a natureza da variável estudada

    Neotropical freshwater fisheries : A dataset of occurrence and abundance of freshwater fishes in the Neotropics

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    The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications

    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora

    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
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