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

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 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset 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 south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards 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 datasets of Neotropical Series which 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 dataset

Adubação nitrogenada e partição de massa em plantas de Brachiaria brizantha cv. xaraés e Panicum maximum x Panicum infestum cv. massai Nitrogen fertilization and dry matter partition in xaraes grass and massai grass

Objetivou-se, com o presente trabalho, avaliar a partição de massa seca em plantas de capim-xaraés (Brachiaria brizantha) e capim-massai (Panicum maximum x Panicum infestum), submetidas a quatro doses de nitrogênio (0, 40, 80 e 120 mg/dm³). O experimento foi realizado em delineamento inteiramente casualizado, com 4 repetições. A semeadura de ambas as forrageiras foi feita em bandejas contendo substrato agrícola comercial e 15 dias após a emergência cinco plantas foram transferidas para os vasos, com volume de 5,8 dm³. Dezoito dias após a transplantação realizou-se o desbaste, deixando-se três plantas/vaso. Quando as plantas atingiram altura média de 35 cm foram submetidas a um corte de uniformização a 5 cm do solo. A adubação nitrogenada foi fracionada em 4 aplicações, e após quarenta e cinco dias em crescimento livre, as plantas foram colhidas e avaliadas quanto aos teores de MS da lâmina, colmo, material morto e raiz. Avaliaram-se também as razões parte aérea:raiz e lâmina:colmo. O nitrogênio exerce efeito na partição de MS de plantas de capim-xaraés, favorecendo o desenvolvimento da parte aérea, sem efeito no sistema radicular. Observou-se também que o nitrogênio favorece a relação lâmina:colmo, além de acelerar o processo de senescência nessas plantas, com conseqüente aumento na deposição de material morto.<br>The experiment was carried out in a greenhouse with the objective of evaluating the dry matter partition of capim-xaraés (Brachiaria brizantha) and capim-massai (Panicum maximum x Panicum infestum) submitted to four treatments of nitrogen (0, 40, 80, and 120 mg/dm3). A randomized design with four replications was applied. Both species were sowed in trays containing commercial agricultural substratum and 15 days after the emergence of five plants they were transferred to 5.8-dm3 vases. When the plants reached an average height of 35 cm, they were cut 5 cm from the soil to achieve a uniform cut. The nitrogen was applied four times. After forty-five days of free development the plants were cut and evaluated for dry matter of the leaf, stem, dead material, and root. The shoot to root and lamina to stem ratios were also evaluated. It was observed, according to the results that the nitrogen affected the dry matter partition of capim-xaraés, favoring the development of the shoot, but without effect on the roots. The total dry matter production of xaraes and massai shoot, as well as the lamina to stem ratio increased linearly with the doses of N, without affecting the root dry matter. It was also observed that nitrogen favors the lamina to stem relation and increases the dead material deposit in xaraes grass and massai grass