Ecosystem Disturbances and Ecosystem Services Chapter 3

Ecosystem Disturbances A large part of environmental science is studying what happens when natural or anthropogenic disturbances occur or predicting what will happen when they do

What is a WATERSHED? It is an area of LAND that water flows across or through downstream on its way to a stream, lake or ocean. The watershed acts like a funnel collecting all the water within an area into a larger waterway. It is also called a Drainage Basin

Watershed Study- Hubbard Creek Deforested watershed vs. forested watershed Take aways: 1) disturbances in ecosystems disrupt natural cycling and systems 2) Forests/vegetation are important for accumulation and maintenance of soil nutrients

Case Study- Haiti

Take aways- 1) poorer nations often rely on cheaper fuels such as raw or less processed biomass like trees and charcoal 2) positive feedback loop - - less trees = more erosion = less vegetation 3) #2 has economic impacts - - less farming, greater impact from natural disasters, less jobs 4) Finding innovative solutions to environmental issues must strike a balance and must acknowledge the connectivity between the environment, human health and well being, and the economy -Related story: Wangaari Maathai

Resistance vs. Resilience Resistance – how much a disturbance affects flows of energy and matter -a disturbance that affects populations and communities but not the flow of energy and matter we say it has high resistance More biodiversity = greater resistance

Resistance vs. Resilience Resiliance – how quickly an ecosystem can recover and return to its original state - more biodiversity = greater resilience Intermediate Disturbance Hypothesis Take away – the more diverse an ecosystem is the better off it is! Restoration Ecology – studies how to reverse effects and restore original ecosystem services EX: wetland remediation

Ecosystem Services Ecosystems provide all of our essential needs: clean water, shelter, clean air, etc. Instrumental value – value based on if the entity can be useful, act as a tool, or provide a service. Can often associate a monetary value with it EX: Water purification Provisions Regulating services Support services Resilience Cultural Services Intrinsic value – moral value or benefit