Human Destruction of BiodiversityKate Foley

Outline

• Importance of biodiversity• Human impacts• Economic value of biodiversity• Impacts of deforestation on biodiversity• Extinction of species

What is Biodiversity?

• Variety of different species within a giving ecosystem, biome, or entire planet.

What is Biodiversity?

• The number of species of plants, animals, and microorganisms, the enormous diversity of genes in these species, the different ecosystems on the planet such as deserts, rainforests and coral reefs are all part of a biologically diverse Earth.

• conservation and sustainable development strategies

Diversity

• Species Diversity- Number of different species and their relative abundance in a given area, related to species richness.

• Ecosystem Diversity- Variety of ecosystems present in a biosphere: variety of forests, grasslands, oceans, lakes, deserts, etc.

• Genetic Diversity- Total number of genetic characteristics in the genetic makeup of a species: Variety in the genetic makeup of organisms of a species that allow the species to reproduce and gain a competitive advantage.

Why is it important?• Stability- Stable environment• Genetic reserves- Genetic diversity• Medicinal- Medicines• Agricultural- Food• Industrial- Building homes• Scientific- Experimental, new technology• Aesthetic-Beautiful!• Ethical- What should we do regarding the environment• Religious- Religious beliefs regarding the environment

Healthy Biodiversity offers many Natural Services• Ecosystem services: protection of water resources, oil

formation and protection, nutrient storage and recycling, pollution breakdown and absorption, climate stability, maintenance of ecosystems.

• Biological resources: food, medicinal resources and pharmaceutical drugs, wood products, ornamental plants, breeding stocks, future resources, diversity in genes.

• Social benefits: Research, education, recreation, tourism, cultural values

Why is it important?

• Biodiversity boosts ecosystem productivity where each species, no matter how small, all have an important role to play.

• Ex: A larger number of plant species means a greater variety of crops, greater species diversity ensures natural sustainability for all life forms, and healthy ecosystems can better withstand and recover from a variety of disasters.

Biodiversity• Weird Moon Lady

Genetic Diversity in Forests

• The genetic diversity of tropical forests is basically the deepest end of the planetary gene pool. • Hidden in the genes of plants, animals, fungi, and

bacteria that have not even been discovered yet may be cures for cancer and other diseases or the key to improving the yield and nutritional quality of foods

• Finally, genetic diversity in the planetary gene pool is crucial for the resilience of all life on Earth to rare but catastrophic environmental events, such as meteor impacts or massive, sustained volcanism.

Biggest threat to Earth’s Biodiversity•HUMANS!!!•Population: Growth of human

population is a major factor affecting the environment, There are now 7 billion people on the earth!

Human Impacts

• Habitat alteration• Over harvesting• Pollution• Introduction of new species• Climate change

Human Impacts on Biodiversity

• We have depleted and degraded some of the earth’s biodiversity and these threats are expected to increase if we do not make a change.

Economic Value

• “At least 40 percent of the world’s economy and 80 percent of the needs of the poor are derived from biological resources. In addition, the richer the diversity of life, the greater the opportunity for medical discoveries, economic development, and adaptive responses to such new challenges as climate change.”

-The Convention about Life on Earth, Convention on Biodiversity wed site

Economic Value• Pharmaceutical- 640 billion, 25-50% derived from genetic

resources• Biotechnology- 70 billion, from public companies alone, Many

products derived from genetic resources (enzymes, microorganisms)

• Agricultural seeds- 30 billion, All derived from genetic resources

• Personal care, Botanical, Food & Beverage industries- 22 billion, 12 billion, and 31 billion respectively. Some products derived from genetic resources. represents ‘natural’ component of the market.

Report from Economics of Ecosystems and Biodiversity for National and International Policy Makers 2009, provided the following example of sectors dependent on genetic resources:

Struggling to Conserve• Unfortunately, despite the effort put into conservation by

organizations and activists, their work can easily be undermined by those who have other interests. This occurs, for example, from habitat destruction, illegal poaching, to influencing or manipulating laws designed to protect species.

• Cost of replacing species, if possible, would be extremely expensive. Therefor it makes more sense to move towards sustainability.

• As we start destroying, reducing, and isolating habitats, the changes for interaction from species with a large gene pool decreases.

Deforestation of Forests• The world’s forests have been exploited to a point of crisis,

major changes in global forest management strategies would be needed to avoid devastation.

• Deforestation on a human scale results in decline in biodiversity is known to cause the extinction of many species. The removal or destruction of areas of forest cover has resulted in a degraded environment with reduced biodiversity.

• Forests provide habitat for wildlife• Deforestation and introduction of non-native species has led

to about 12.5% of the world’s plant species to become critically rare.

Fig. 10-4, p. 193

Support energy flow and chemical cycling

Reduce soil erosion

Absorb and release water

Purify water and air

Influence local and regional climate

Store atmospheric carbon

Provide numerous wildlife habitats

ForestsNatural Capital

Fuelwood

Lumber

Pulp to make paper

Mining

Livestock grazing

Recreation

Jobs

EconomicServices

EcologicalServices

Types of Forests

• Old Growth Forest: uncut or regenerated forests that has not ben seriously disturbed for several hundred years.• Account for 22% of the

world’s forest.• Hosts many species with

specialized niches.

Types of Forests• Second Growth Forest: is a forest which has re-grown

after a major disturbance such as a fire, insect infestation, timber harvest, until a long enough period has passed so that the effects of the disturbance are no longer evident.

Harvesting Trees

• Humans build roads into previously inaccessible forests which paves the way for fragmentation, destruction, and degradation.

Deforestation

• Large areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rate.

• Deforestation and increased road building in the Amazon Rainforest are a significant concern because of increased human movement into wild area, increased resource extraction and further threats to biodiversity.

Humans affecting biodiversity

Habitat Loss, Degradation, and Fragmentation• Conservation biologists summarize the most important causes of premature extinction as “HIPPO”: • Habitat destruction, degradation, and

fragmentation• Invasive species• Population growth• Pollution• Overharvest

Fragmentation

• Reduction in the total area of the habitat• Decrease of the interior : edge ration• Isolation of one habitat fragment from other

areas of habitat• Breaking up of one patch of habitat into several

smaller patches• Decrease in the average size of each patch of

habitat

Implications of Fragmentation

• Reduction of available amount of habitat:• Plants are usually directly destroyed• Mobile animals (birds and animals)- retreat

into remnant patches of habitat. This leads to crowding effects and increased competition

• Mobile animals can move between fragments of the habitat, but It is very difficult and dangerous(unless you’re a bird).

Implications of Fragmentation

• Size of fragment will influence the number of species which are present:• Small fragments can only support small populations of

plants and animals, and are more vulnerable to extinction.

• Minor fluctuations in climate, resources, or other factors that would be unremarkable and quickly corrected in large populations can be catastrophic in small, isolated populations. Thus fragmentation of habitat is an important cause of species extinction.

Biodiversity and Deforestation

• Many species are so specialized to microhabitats within the forests and their specialization makes them vulnerable to extinction.

• Vulnerable: organisms in the fragments of forest that remain also become increasingly vulnerable, sometimes to extinction.

• Edges of fragmentation: dry out and are buffeted by hot winds, mature rainforest trees often die standing at the margins.

• Changes in the types of trees, plants, and insects that can survive in the fragments rapidly reduces biodiversity in the forest that remains.

Loss of Biodiversity: Extinction

• Human activity had ben causing massive extinctions for a long time.

• The current extinction crisis is the first to be cause by a single species … US!

• Happening faster than ever, a few decades versus thousands to millions of years.

• Humans are not only eliminating species, but also the environment. Ex. Tropical Rainforest

Extinction

• Extinct: Complete disappearance of a species from the earth.• Ex. Dinosaurs

Loss of Biodiversity• In different parts of the world, species face different levels and

types of threats. But overall patterns show a downward trend in most cases.

• Threats of extinction• 1 out of 8 birds• 1 out of 4 mammals• 1 out of 4 conifers• 1 out of 3 amphibians• 6 out of 7 marine turtles• 75% of genetic diversity of agricultural crops has been lost• 75% of the world’s fisheries are fully or over exploited• Up to 70% of the world’s known species risk extinction if the

global temperatures rise by more than 3.5°C

What Can We Do?

• Take immediate action to preserve world’s biological hot spots.

• Keep old growth intact• Ensure that the full range of the earths

ecosystems are included in global conservation strategy.

• Make conservation profitable.• Initiate ecological restoration products to heal

some of the damage done and increase share of earth’s land and water allotted to the rest of nature.

What else can we do?• Cute Bee Video!

Expected Learning Outcomes

•Definition of biodiversity• Importance of biodiversity•Effects of deforestation