A microbial perspective: Exploring the impacts of invasive Himalayan blackberry on soil bacterial diversity in BC's temperate rainforests

Invasive plant species have continued to spread globally at unprecedented rates, negatively impacting ecosystems dynamics. Notably, previous studies on invasive plants have emphasized their influence on native plant and animal species, opposed to soil microbiology. However, understanding their effects on microbes is crucial, as microbes play significant roles in the ecosystems they inhabit. This project seeks to strengthen our understanding on such interactions, by questioning and exploring how invasive Himalayan Blackberry affects soil bacterial diversity. Despite Himalayan Blackberry being the most common invasive plant in southwest BC, there is no existing literature on its soil microbial effects. Given the global significance of BC's coastal biodiversity, understanding the impacts of this invasive species is pivotal. To analyze the bacterial diversity of the soil, four samples will be collected at five sites. Specifically, a twelve-inch probe will be used to obtain soil core samples from beneath Himalayan blackberry and native Salal. The soil samples will be processed and diluted before being plated on nutrient agar, and incubated at room temperature for two weeks. Richness, abundance and Simpson’s diversity will be calculated for each plate once the colonies have grown. The averaged results across the invaded and non-invaded soil conditions will be compared using an independent sample's t-test, with a p–value of 0.05. It is expected that the average bacterial diversity indices in invaded soils will be lower compared to the average indices of non-invaded soils. Overall, this study aims to improve our knowledge of the cascading effects plant invasions have on our coastal ecosystems. Poster submission was sponsored by Dr. Jessie Clasen, (Science and Technology Department) and was presented at the New Westminster campus on April 10, 2025, for Student Research Days 2025.