Determination of homogeneous zones for liming recommendations of black pepper using geostatistics

ABSTRACT Studies aimed at determining homogeneous zones and the spatial variability of soil characteristics may improve the efficiency of agricultural input applications. The purpose of this study was to determine homogeneous zones for liming applications and to characterize the spatial variability of characteristics related to soil acidity and productivity in an Oxisol cultivated with black pepper (Piper nigrum L.). This study was carried out in São Mateus, state of Espírito Santo, Brazil. The experimental site was 100 x 120 m. A grid with 126 sampling points was established. Three soil sub-samples were collected at each sampling point in the black pepper canopy areas, at a 0-0.20 m depth. Crop productivity was estimated by harvesting the three plants neighboring each sampling point. Descriptive statistics and geostatistical analyses were performed. Homogeneous management zones were defined based on map of liming needs. Mathematical models adjusted to semivariograms indicated that all of the studied variables exhibited spatial dependency. An analysis of the spatial variability together with the definition of homogeneous zones can be used to increase the efficiency of soil liming

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 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