Land And Water Pt.2

The Tragedy of the Commons

In 1968, ecologist Garrett Hardin described the “tragedy of the commons”.

It describes the tendency of a shared, limited resource to become depleted because people act from self-interest for short-term gain.

Externalities

a cost or benefit of something that is not included in the purchase price of the product or service.

In environmental science we are concerned about negative externalities because of the environmental damage for which no one bears the cost. 

Primary (old growth) Forest

Natural forest uncut by people. Little remained by the 20th century

Harvesting timber: Clear Cutting

• All trees in the area are cut

• Most cost-efficient

• Greatest impact on forest ecosystems

• May mimic some natural forms of disturbance

• Destroy entire ecological communities

• Soil erosion

• Public outrage

National Parks

managed for scientific, educational, and recreational use, and sometimes for their beauty or unique landforms. (Yellowstone, Grand Canyon)

Managed Resource Protected Areas

managed for the sustained use of biological, mineral, and recreational resources.

Urban Sprawl

Urbanized areas that spread into rural areas creating suburbs.

The four main concerns of urban sprawl in the U.S. are:

- automobiles and highway construction

- living costs (people can get more land and a larger house in the suburbs for the same amount of money)

- urban blight (city revenue shrinks as people move to the suburbs) 

- government policies

Urban decay (Positive Feedback Loop)

 (urban blight) - the process where a functioning city, falls into disrepair

Smart Growth for Sustainable Communities

- Mixed land uses

- Create a range of housing opportunities and choices

-Create walkable neighborhoods

- Builds on vacant lots within cities rather than expanding into new land outside the city - Infill

- Encourage community and stakeholder collaboration in development decisions

- Compact building design

-Focus on energy and resource conservation

-Conserve natural habitats, farmland, open spaces and critical environmental areas

- A variety of transportation choices

- Strengthen and direct development toward existing communities

- Make development decisions predictable, fair and cost-effective