Biology 2483A Lecture 16: Lecture 16 - Change in Communities

• School: Western University
• Department: Biology
• Course: Biology 2483A
• Professor: Hugh Henry

Document Summary

Mount st. helens (1980): new habitats devoid of living organisms. Communities change over time, and one of the ways we see this, is when we see recovery from natural disasters such as the eruption of mount st. helen. Effects of the eruption varied depending on distance from the volcano and habitat type. Others were in burrows, or under ice-covered lakes, or were plants with underground parts. Grassy meadows, their preferred habitat, expanded after eruption. Their burrowing activities facilitated plant succession by bringing organic soil, seeds, and fungal spores to the surface thus plant growth increased where there was increased gopher activity. Newly-formed and isolated ponds were colonized by amphibians much faster than was thought possible. Frogs and salamanders were using tunnels created by northern pocket gophers to make their way from one pond to another. Multiple mechanisms were responsible for primary succession: facilitation by dwarf lupines on the pumice plain.