ENV234H1 Lecture 14: Ecosystem management & Restoration
Document Summary
Lecture 14 (lecture 13 slides) ecological succession: communities are. At different times have disturbances: = things that remove plants or have major impact on how many plants there are. Severity of disturbances shown on graph: very severe: glaciers and volcanoes. Volcanoes erupt, burn everything, cover everything in lava. Major disturbances send community to primary succession: milder disturbances: wars, mining. May send a region to primary succession or send a place to secondary succession: mild disturbances: agriculture, fire, hurricane. Bare rock: no remnant organisms, place has to be colonized from organisms outside. Ex: sand dunes: poor/no substrate, very hardy plants that manage to make habitat. On disturbed site: soil present (have substrate for plants to anchor in, some live organisms and seeds remaining. Recolonization by: seed bank, vegetative growth. Underground runners of plants that re-sprout: dispersal. May have burned all the big trees but may have seeds in soil: old-field. Stop agriculture and allow field to grow out.
