A study of habitat fragmentation in Southeastern Brazil using remote sensing and geographic information systems (GIS)

The purpose of this work was to study fragmentation of forest formations (mesophytic forest, riparian woodland and savannah vegetation (cerrado)) in a 15,774-ha study area located in the Municipal District of Botucatu in Southeastern Brazil (São Paulo State). A land use and land cover map was made from a color composition of a Landsat-5 thematic mapper (TM) image. The edge effect caused by habitat fragmentation was assessed by overlaying, on a geographic information system (GIS), the land use and land cover data with the spectral ratio. The degree of habitat fragmentation was analyzed by deriving: 1. mean patch area and perimeter; 2. patch number and density; 3. perimeter-area ratio, fractal dimension (D), and shape diversity index (SI); and 4. distance between patches and dispersion index (R). In addition, the following relationships were modeled: 1. distribution of natural vegetation patch sizes; 2. perimeter-area relationship and the number and area of natural vegetation patches; 3. edge effect caused by habitat fragmentation, the values of R indicated that savannah patches (R = 0.86) were aggregated while patches of natural vegetation as a whole (R = 1.02) were randomly dispersed in the landscape. There was a high frequency of small patches in the landscape whereas large patches were rare. In the perimeter-area relationship, there was no sign of scale distinction in the patch shapes, In the patch number-landscape area relationship, D, though apparently scale-dependent, tends to be constant as area increases. This phenomenon was correlated with the tendency to reach a constant density as the working scale was increased, on the edge effect analysis, the edge-center distance was properly estimated by a model in which the edge-center distance was considered a function of the to;al patch area and the SI. (C) 1997 Elsevier B.V. B.V

Synopsis of the species of Myxobolus Butschli, 1882 (Myxozoa: Myxosporea, Myxobolidae) described between 2005 and 2013

A synopsis of the species of Myxobolus Butschli, 1882 (Myxozoa, Myxosporea, Myxobolidae) described between 2005 and 2013 is presented, including 112 nominal species. For each species the most important morphological and morphometric features are indicated in tabulated format. Included are also accession numbers for molecular data (when available), site of the infection within the host, features of the vegetative stage, organ infected, etc., plus a full bibliography of the original records for these species.A synopsis of the species of Myxobolus Butschli, 1882 (Myxozoa, Myxosporea, Myxobolidae) described between 2005 and 2013 is presented, including 112 nominal species. For each species the most important morphological and morphometric features are indicated in tabulated format. Included are also accession numbers for molecular data (when available), site of the infection within the host, features of the vegetative stage, organ infected, etc., plus a full bibliography of the original records for these species

Data from: Long-term isolation at a low effective population size greatly reduced genetic diversity in Gulf of California fin whales

The Gulf of California, Mexico is home to many cetacean species, including a presumed resident population of fin whales, Balaenoptera physalus. Past studies reported very low levels of genetic diversity among Gulf of California fin whales and a significant level of genetic differentiation from con-specifics in the eastern North Pacific. The aim of the present study was to assess the degree and timing of the isolation of Gulf of California fin whales in a population genetic analysis of 18 nuclear microsatellite genotypes from 402 samples and 565 mitochondrial control region DNA sequences (including mitochondrial sequences retrieved from NCBI). The analyses revealed that the Gulf of California fin whale population was founded ~2.3 thousand years ago and has since remained at a low effective population size (~360) and isolated from the eastern North Pacific (Nem between 0.89–1.4). The low effective population size and high degree of isolation implied that Gulf of California fin whales are vulnerable to the negative effects of genetic drift, human-caused mortality and habitat change.,Microsatellites_GC_NP_fin_whalesMicrosatellite genotypes from Rivera-León et al. (2019) Long-term isolation at a low effective population size greatly reduced genetic diversity in Gulf of California fin whales in Scientific Reports"MtDNA_sequences_Gulf_California_NP_fin_whalesMitochondrial control region DNA sequences from Rivera-León et al. (2019) Long-term isolation at a low effective population size greatly reduced genetic diversity in Gulf of California fin whales in Scientific Reports"

Etudes des effets de l'entrainement et du vieillissement sur la fibre musculaire

CNRS AR 11264 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc