Trash in Streams Data

Methods

Data were collected on trash in 10 streams around Mecklenburg County, North Carolina and 14 stream reaches around Cuyahoga County, Ohio in 2021 and 11 reaches again in 2024. Data collected included information on the trash itself (e.g., material, size) and its location within in the stream (e.g., what it was touching, whether any bed material had eroded or deposited around it). Within the 50 m reach, 4-6 transects were created across the stream and every piece of trash within 2 m of the transect was included.

Workflow

The workflow for this starts with raw data on trash in streams and their locations. The data were put through a cluster analysis to create morphospecies of trash (e.g., glass items, plastic bags, plastic bottles) and microhabitats within the stream. These morphospecies and microhabitat numbers were the basis for further analysis. Abundance matrices of these habitats and species were created. Environmental, land use, and stream reach data were also included in the further analysis.

Files

01 Raw data

Field data: trash_data.csv The original datasets transcribed from field datasheets. For explanations of the variables look at definitions.csv
Stream reach, land use, and other environmental variables: env_variables For explanations of the variables look at definitions.csv
GPS locations: gps_coordinates These are GPS coordinates for the stream reaches. It was not included in the analysis.

02 Cluster analysis

Cluster analysis uses the trash_data.csv in the cluster_analysis.R file.
Libraries required: factoextra, corrplot, fpc, cluster, writexl
The results of the two clustering analyses are in cluster_results.csv. The numbering of the cluster was adjusted to be more logical and those results are in new_cluster_numbers.csv

03 Data analysis

Diversity analysis uses the new_cluster_numbers.csv in diversity_analysis to calculate Shannon's diversity indices on the reaches. If t tests and/or ANOVAs are done, use diversity_scores.
Library required: picante
NMDS analysis uses specieshabitat_abundancematrix in nmds_analysis.R Further NMDS analysis included env_variables and specieshabitat_abundancematrix.csv in nmds_with_envfit
Library required: vegan, vegan3d
PERMANOVA analysis uses specieshabitat_abundancematrix in permanova_analysis
Libraries required: vegan, pairwiseAdonis

References:

U.S. Geological Survey (USGS), 2019, Annual NLCD Collection 1 Science Products: U.S. Geological Survey data release, https://doi.org/10.5066/P94UXNTS.