Authors

• Michelle Talal– Oregon State University
• Mary Santelmann – Oregon State University
• Hattie Greydanus – Oregon State University

Purpose

This research aims to understand plant composition patterns in urban parks of Portland, Oregon, and to describe some of the environmental variables and plant traits present in different types of urban parks.

Description

Urban parks are a type of green infrastructure that have the potential to promote habitat and biodiversity conservation, as well as provide a range of physical, psychological, and social benefits for people. Understanding the needs and desires of park visitors can be useful for assisting urban planners and park managers by providing information on human benefits and potential areas for improvement in urban parks. I used a stratified random sampling design to select 15 urban parks within the Portland city boundary, from which I collected vegetation data in five 400-m² square plots in each park. Additionally, I sampled five 1-m² square subplots for herbaceous species and cover within each of the 400-m² plots. Plant trait data were obtained from the USDA Plants Database and other local guides, and the wetlands data were collected from the US Fish and Wildlife Service Wetland Mapper. I will analyze the data using a variety of non-parametric multivariate statistics such as hierarchical agglomerative clustering, multi-response permutation procedure, and non-metric multidimensional scaling.

Attributes

Percent cover data for species of trees, saplings/shrubs, herbs, and vines, park type (i.e., binary variables for natural-passive use, multi-use, and recreational-active use), wetland presence (binary variable) (National Wetland Inventory [NWI]) within each park, landform (i.e., binary variables for majority hillslope, majority terrace), local relief (i.e., binary variables for concave, flat, mixed, and concave), percent slope, percent bare ground, elevation (meters), date of park establishment, total park acreage, and beta diversity (half changes), growth form (i.e., binary variables for herb, vine, sapling/shrub, and tree), group (i.e., binary variables for fern, horsetail, gymnosperm, monocot, and dicot), legal status (i.e., binary variables for native, non-native, invasive, and unknown), and growth duration (i.e., binary variables for annual, biennial/combination of growth patterns, and perennial).