Biodiversity, Conservation, and Environmental Issues: A Comprehensive Guide

Biodiversity

Biodiversity = Number, variety and variability of Earth’s organisms (of plants and animals)

Levels of Biodiversity

1. Genetic Diversity - The genetic variety within all populations of that species.

2. Species Richness - The number of species

3. Ecosystem Diversity - The variety of ecosystem found on earth. Ex, The forests, prairies, deserts, coral reefs, lakes

Endangerment and Extinction

Species of imminent danger of extinction throughout all or a significant portion of its range.

The death of the last individual of a species.

Leading Causes of Endangerment and Extinction

• -land use of biodiversity hotspots(biggest contributor to species loss)
• -The introduction of a foreign species into an ecosystem from  which it did not evolve.
• -Overexploitation: species become extinct or endangered as a result of deliberate efforts to eradicate or control their numbers
• -Commercial harvest: the collection and sale of live organisms from nature.
• -Pollution

Characteristics of Species Prone to Extinction and Endangerment

low reproductive rates, specific food intake or reproductive requirements: Limited natural ranges.

Small Range and population size, requiring large territory, living on an island, requiring specialized breeding

Conservation Biology

Study of human impact on organisms and protect biological diversity.

Conservation Methods

In Situ: ie. establish parks and refugees

Ex Situ: te. Captive breeding (zoo)  and genetic modification

Biodiversity Hotspots

Small land w/ high number of Endemic Species with a high risk from human activities.

25 Hotspots (15 tropical and 9 are islands)

Habitat Fragmentation and Restoration

Habitat Fragmentation

Habitat fragmentation= The division of habitats that formerly occupied large, unbroken areas into smaller areas by road, fields cities.
Its impacts= 1.Large areas broken into smaller. 2.Low biodiversity.

3.Habitat Corridors = strips of habitat that connect isolated habitat fragments (allows animals to move from one fragment to another safely)  4.Introduction of foreign species and overexploitation and pollution

Habitat Restoration

(IN-situ): Goal is to reintroduce organisms back to their natural habitat.

“Save organisms from extinction” ¤ Artificial insemination ¤ Embryo transfer ¤ Surrogate mothers ¨

Zoos, aquaria, botanical gardens, and seed banks = -save individual species from extinction by artificial insemination, -embryo transfer, -surrogate mothers, -seed banks (stored seeds safe from habitat destruction)

Conservation Practices

IN Situ: establish refuges and parks

Ex Situ: captive breeding and genetic mod

* ESA ¨ Endangered Species Act (ESA) 1973 ¤ Authorized protection of endangered and threatened species n Makes it illegal to sell or buy any product made from an endangered species ¤ Currently 1300 species are listed in US ¤ Species are designated as endangered or threatened based on biological grounds

Land Use

World Land Use

World land use: (3% cities),( 38% agriculture), (30% land consists of rock, ice, tundra, desert), (29% natural ecosystems ex: forests).
US land use: (55% owned by citizens/corporations) (3% native tribes) (35% federal government) (7% state and local gov)

Major Federal Land Owners and Land Use

• Bureau of Land Management (Dept of Interior): national resource lands, 270 million acres, used for mining, livestock, grazing, oil and natural gas extraction

• U.S. Forest Service (Dept of Agriculture): National forests, 191 million acres, used for logging, recreation, conservation of watersheds, wildlife habitat, mining, livestock grazing, and oil and natural gas extraction

• U.S. Fish and Wildlife Service (Dept of Interior): National wildlife refuges, 95 million acres, used for wildlife habitat, logging, hunting, fishing, mining, livestock, and oil and natural gas extraction.

• National Park Service (Dept of Interior): National Park system, 84 million acres, used for recreation and wildlife habitat.

• Other- includes Dept of Defence, Corps of Engineers, and Bureau of Reclamation: 72 million acres, Remaining federal lands, used for military and wildlife habitat.

Forest Management

= conserve forests for the commercial harvest of timber and non-timber forest products, AND  sustain biological diversity, prevent soil erosion, protect the soil, and preserve watersheds that produce clean water.

Forestry Practices

• Monoculture: areas covered only by one crop, ecological simplification,these are prone to damage from insects and disease-causing-microorganisms.

• Selective Cutting: older trees are harvested from time to time and the forests regenerates naturally. Fewer negatives than the other methods, but it is not profitable in the short term.

• Shelterwood Cutting: Less desirable and dead trees are harvested. As the younger trees mature, they produce seedlings, which continue to grow as the now-mature trees are harvested. Little soil erosion occurs, but more trees are removed than selective cutting.

• Clear Cut: Cut all trees down and leave the stumps. This is most cost-effective way to harvest trees and provides few benefits for some wildlife, such as deer and songbirds. However, clear cutting causes landslide, soil degradation, destroys biological habitats, and is ecologically unsound.

• Seed Tree Cutting: removes all but a few big trees, which provide seeds for natural regeneration.

• Deforestation: It is the “most serious problem facing the world”. Causes include forest fires, land-clearing practices, agriculture, construction, tree harvests, and insects/disease. It results in decreased soil fertility, uncontrolled soil erosion, formation of deserts, extinction, regional climate change, ocean acidification, and increase in global temperature. THIS SHIT IS NOT GOOD

Understand what rangelands are and their benefits/impacts

rangelands= land that is not intensely managed and used for grazing livestock..  
PROS: ⅔ privately owned, Forests cut down for rangeland, If under carrying capacity can renew land . Often over burdened soil and non renewable.

CONS: Overgrazing leaves ground barren ¤ Animals exceed land’s carrying capacity ¨ Land degradation ¤ Natural or human-induced process that decreases future ability of land to support crops or livestock ¨ Desertification ¤ Degradation of once fertile land into nonproductive desert

Understand what agricultural lands are and their benefits/impacts
Agricultural lands/prime farmland= has right soil, conditions and water to produce food, forage, fiber, and oilseed crops.

CONS: urbanization, loss of rural land

Understand what wetlands are and their benefits/impacts

*Wetlands= Covered by shallow of water for at least half the year

*PROS: Habitat for organisms, purify natural water, “recharge” ground, protect coastal erosion, provide commercially important products, reduce damage from flooding

CONS: Often converted to agricultural land, residential or industrial. Dredging for nav, dams and mining.

Understand coastal management and the importance of wetlands

Coastal management= deals w/ eco development of a thin strip of land bordering the ocean

Importance of wetlands= Provides food and shelter for many aquatic species

Chapter 21
Understand major issues related to water quality

Water pollutants

Types of water pollutants

Eight Categories: 1.Sewage, 2.disease-causing agents, 3.sediment pollution, 4..inorganic plant and algal nutrients, 5.organic compounds,6.  inorganic chemicals, 7. radioactive substances, 8. thermal pollution

Sources of pollution

Chemicals added to the atmosphere by natural events or human activities high enough in concentration to be dangerous.

Point source vs. nonpoint source pollution

Point Source: Water pollution that can be traced to a specific origin

Nonpoint source pollution: Pollutants that enter bodies of water over large areas rather than being concentrated at a single point of entry

How can we improve water quality

What is eutrophication?

Slow-flowing stream, lake or estuary enriched by inorganic plant and algal nutrients such as: High nutrient levels, poor light penetration, low dissolved oxygen levels, shallow waters, high algal growth

Waste water= industrial liquid waste and sewage in towns and urban areas.

How do we treat wastewater?

-Primary Treatment=Removing suspended and floating particles by mechanical processes

-Secondary Treatment=Treating wastewater biologically to decompose suspended organic material; reduces BOD

-Tertiary Treatment=:Advanced wastewater treatment methods that are sometimes employed after primary and secondary treatments

Know the different types and sources of air pollution

• Primary Pollution: Harmful substance emitted directly into the atmosphere

(Major ones are oxides, nitrogen oxides, sulfur dioxide, particulates, and hydrocarbons)

• Secondary Air Pollution: Harmful substance formed in the atmosphere when a primary air pollutant reacts with substances normally found in the atmosphere or with other air pollutants. (Major ones are sulfur and sulfur trioxide)

• Most significant amount of air pollution comes from densely populated urban areas

• 7 most important types of air pollutants: particulates, lead,  nitrogen oxides, sulfur oxides, carbon oxides, hydrocarbons, ozone, and air toxics

• Sources of Air pollutants: transportation (57%), Fuel Combustion- except in vehicles (21%), industrial processes (12%), and misc (10%).

• Air pollutants: Carbon Monoxide (50.9%), Nitrogen oxides (11.6%), particulates (11.6%), volatile organics (9.5%),  sulfur dioxide (8.5%), particulates PM 2.5 (3.6%), Ammonia (2.3%), and lead (2%).

What are the basic impacts from Air Pollution

*Air pollution= various chemicals present in high enough levels in the atmosphere to harm humans, other animals, plants or materials.

*Impacts= Global Warming, Smog, Photochemical smog

Human Health: Exposure to pollution can irritate the eyes, inflame the respiratory tract, suppress the immune system, increase susceptibility to infection, chronic respiratory disease like emphysema and chronic bronchitis

Environmental Impacts: ozone depletion from CFC’s, acid deposition, forest decline, groundwater contamination,

-Acid Deposition: acid falls from the atmosphere as precipitation or as dry acidic particles. They react with water to produce sulfuric acid. It kills aquatic life, harms forests, and attacks metals.

-Pollution is worse in developing countries due to rapid industrialization, growing automobiles, and lack of emission standards.

How do we regulate and control Air Pollution in the US

Mitigation: Limiting greenhouse gas emissions to moderate global climate change

-Air quality in the US has slowly improved since passage of the Clean Air Act in 1970. This allows EPA to set limits on how much specific air pollutants are permitted in the US. Most dramatic improvement has been decline of lead in the atmosphere, although sulfur oxides, nitrogen oxides, ozone, carbon monoxide, volatile organic compounds and particulates have also been reduced.

What is Ozone Depletion in the Stratosphere

Stratospheric Ozone Thinning: The accelerated destruction of ozone in the stratosphere by human-produced chlorine and bromine containing chemicals. The primary chlorine releasing chemicals are CFCs which are used in aerosol cans, fridges, air conditioners, etc. Pesticides, fire retardants and industrial solvents also contain chemicals that release chlorine and bromine, thus adding to ozone depletion.

What is Acid Deposition and how do we deal with it?

Acid Deposition is what occurs when sulfur dioxide and nitrogen oxides released into the atmosphere, combine with moisture to form acids and then deposit onto the land through rain, snow or dew.  EX: vehicles (nitrogen oxide), coal burning plants/boilers (sulfur dioxide)
Installing scrubbers in smokestacks and using clean-coal technologies will diminish acid deposition.

What are the major causes of climate change?

Damage to Ecosystems (Coral reefs, ice caps)

Rising sea levels

What are the major concerns related to climate change?

What are some measures we can implement to deal with climate change?

Increase efficiency of cars and trucks

Carbon capture and storage

Plant and maintain trees to naturally sequester carbon

Use alternative fuels to fossil fuels

What are the potential impacts from climate change to our environment? To humans?

Rising sea levels- move further inland

Shifting agricultural zones

What is sustainability?

Ability to meet humanity’s current needs without compromising the needs to future generations

What are the three pillars of sustainability?

1. Social 2.Economic 3.Environment

How can we make our communities more sustainable?

• 1. Eliminating poverty and stabilizing the human population

• 2. Protecting and restoring Earth’s resources

• 3. Providing adequate food for all people

4. Mitigating climate change

• 5. Designing sustainable cities