BIOL 191 | Ch. 47 | Biodiversity Conservation

Biodiversity

Encompasses the genetic diversity of species, the variety of species, and the different ecosystems they form

Conservation biology

Aims to protect biological diversity at all levels

Why should people be concerned about the loss of biodiversity?

• Humans depend on plants, animals, and microorganisms for a wide range of food, medicine, and industrial products

• Ecosystems provide an array of essential services, such as clean air and water

• Humans have an ethical responsibility to protect what are our only known living companions in the universe

Examples of economic value of biodiversity include;

• Pharmaceutical industry

  • Plant and animal products

• Agriculture and natural products

  • Plants and animals (food)

Natural essential services

Beyond the direct economic gains from biodiversity humans benefit enormously from the essential services that natural ecosystems provide

Relationships between ecosystem function and biodiversity

• Diversity-stability hypothesis

• Redundancy hypothesis

• Keystone hypothesis

• Idiosyncratic hypothesis

Diversity-stability hypothesis

Species-rich communities are more stable than those with fewer species

Redundancy hypothesis

Ecosystem function levels off at higher levels of diversity due to redundancy

Keystone hypothesis

Ecosystem function dramatically rises as biodiversity approaches its natural levels

Idiosyncratic hypothesis

The relationship between species diversity and ecosystem function can be unpredictable

Plots with more species had;

Increased productivity, used more nutrients, and had less invasive species

Methods for targeting areas for conservation:

1. Identify mega-diversity countries (countries with the greatest number of species)

2. Consider the number of endemic species & target biodiversity hot spots

3. Conserve areas that are representative of all major habitats

4. The last of the wild: focus on preserving regions that are relatively untouched by humans

Proactive conservation

Megadiversity and “last of the wild”

Reactive conservation

Biodiversity hot spots and crisis ecoregions

Preserve design incorporates principles of island biogeography and landscape ecology

Wildlife preserves can be considered “islands” surrounded by a “sea” of human-altered habitat

Landscape ecology

Examines the spatial arrangement of communities and ecosystems in a geographic area

Preserve design

Incorporation of movement corridors and the minimization of edge effects

Indicator species

Status provides information about overall health of ecosystem

Umbrella species

Occupy large habitats so protection extends to many other species

Flagship species

Large or instantly recognizable species

Keystone species

Has a special/critical role within a community (e.g., beavers)

• Not numerous or ecologically dominant, but if removed, drastically affect community (e.g., pollinators) (75% of angiosperms are dependent on insect pollinators)

Restoration ecology

Can involve habitat restoration as well as reintroductions and captive breeding

Complete restoration

Attempt to put back exactly what was present prior to disturbance

Rehabilitation

Return habitat to something similar, but less than full restoration

Ecosystem replacement

Original system is replaced with a different ecosystem; used when terrain is drastically altered

Reintroducing species

To areas where they previously existed can reestablish populations; many reintroduced animals come from captive breeding programs

• Zoos, aquariums, and botanical gardens often play a key role in conservation education and captive breeding programs

Cloning endangered species

Attempts to clone endangered species have yielded mixed results; a number of issues remain unsolved

• Reproductive cycles and embryo nutritional needs are often unknown

• Surrogate mothers of similar species have to be found

• Cloning might not be able to increase genetic variability of the population

• Cloning does not address the underlying causes of driving species loss

How to cope with living

• Take control of the situation

• Recognize predictability

• Find an outlet for frustration

• Maintain social support

• Learn that stressors need not to be stressful, when they are perceived as being fun