DOI: 10.5285/47f036c4-e319-4825-9cb8-f27977eb20dd
title: Impacts of chronic radiation exposure on reproduction, development and genetic diversity of the freshwater crustacean Asellus aquaticus at Chernobyl

description: This dataset contains morphological data from the isopod crustacean, Asellus aquaticus collected from Chernobyl affected areas of Belarus and Ukraine in 2015. This data was collected to calculate fluctuating asymmetry, a measure of developmental stability, in organisms along a gradient of radiation contamination. Five different morphological characters were measured and fluctuating asymmetry (right side minus left side) was calculated. Fluctuating asymmetry was calculated here as FA2: [|R-L|/(R+L)/2)] where R and L represent measurements in micrometres for right and left sides of the five morphological characters. Number of segments represents raw right minus left data for the number of antennal segments and is thus provided in a separate column. All data provided are means of two independent measurements. In addition, a measure of environmental factors and total dose rates are also provided in this dataset. Blank cells indicate where no data was available.
description: The data comprises a series of experiments to assess the impacts of chronic radiation exposure at Chernobyl on the development, reproduction and genetic diversity of the freshwater crustacean, Asellus aquaticus. Field samples were collected from six lakes of varying contamination in Belarus and the Ukraine in 2015 and 2016 using kick netting and immediately preserved in ethanol and returned to the Institute of Marine Sciences, University of Portsmouth. Development was assessed using the fluctuating asymmetry technique, which assesses deviations from the expected perfect bilateral symmetry of an organism. Presented data is the results of the FA2 assay: FA2 = mean [| R − L | / (R + L) / 2)] where R and L represent measures of the right and left side of the organism in µm respectively. Measurements were conducted blind using Image J (v1.48) on randomly coded images obtained using a Leica DFC130 camera. Data is provided for two sampling periods; 2015 and 2003-2005 (conducted by colleagues at the Belarusian National Academy of Sciences).  Reproduction was assessed by analysis of fecundity and the proportion of gravid females at each site. Data presented includes number of eggs, weight of eggs (in milligrams), female weight (in milligrams), weight-normalised egg numbers (in milligrams) and sampling dates. Weights were obtained using a Kern ABT 120-5DM analytical fine balance with a precision of ± 0.02 mg. Data is presented from two sampling years at six sites of varying contamination. Dose rates are also provided, calculated using ERICA based on deposition values at the corresponding site. Finally, genetic diversity was calculated following genotyping-by-sequencing analysis conducted at the genomic diversity facility, Cornell University, New York. Data provided includes a number of routinely used genetic diversity parameters calculated at both the individual level (inbreeding coefficient, F, observed and expected heterozygosity) and population level (Tajima’s D & Nucleotide Diversity). This data was generated using the UNEAK pipeline within TASSEL software (v 3.0) by bioinformatics analysists at Cornell University. Tajima’s D & Nucleotide were calculated using the PopGenome package in R Studio.