CADStat: Statistical Tools for Causal Analysis

Calculating Trait Metrics

Introduction

This module calculated trait metrics from biological data. Available traits include physical habits (e.g., clinger, sprawler, etc.) and feeding habits (e.g., shredder, collected/gatherer). The tool summarizes biological data in terms of three metrics for each trait class: relative abundance, relative richness, and richness. For example, selecting the physical habitat trait file will return a data frame with the relative abundance, relative richness, and richness of clingers, sprawlers, and other physical habits in the data.

The module is initiated by choosing Analysis Tools -> Calculate Trait Metrics from the menus. A dialog box should appear as follows:

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Input files

Active Dataset: This file is a data frame that contains observations of benthic macroinvertebrate. The file can be selected from the working directory or loaded using the Browse option. At least three columns are required in this data frame: (1) a unique sample identifier (specified by selecting the appropriate field in Site ID:, (2) taxon names (specified in Taxon Name, and (3) the number of individuals of a particular taxon within a particular sample (Taxon Count).

Coefficient data: Select a file with species traits Two trait files are currently available: physical habit (trait.habit) and feeding habit (trait.feeding).

Output file

Results: Select this option to save the results of the script in a separate text file.