Chapter 43 Global Ecology and Conservation

1.8 million

How many species have been formally names and described?

5-100 million

How many species are estimated by scientists to exist?

Extinction

Human activities alter natural disturbances, trophic structures, energy flow, and chemical cycling and we are pushing many species toward ____________.

Conservation Biology

The integrated study of ecology, evolutionary biology, physiology, molecular biology, and genetics to sustain biological diversity at all levels. This field studies and develops efforts to sustain ecosystem processes and stem the loss of biodiversity.

Genetic diversity, species diversity, and ecosystem diversity

What are the three levels of biological diversity?

Genetic Diversity

Genetic variation within a population and between populations associated with adaptations to local conditions.

Species Diversity

The number and relative abundance of species in an ecosystem. Generally, the number of species in an ecosystem or across the biosphere.

Endangered Species

A species that is in danger of extinction throughout all or a significant portion of its range.

Threatened Species

A species that is considered likely to become endangered in the foreseeable future.

Ecosystem Diversity

The variety of ecosystems on Earth

Negative

The local extinction of a species can have a _______ impact on other species in the ecosystem.

Overgrazing, diversions, organisms

Human activities like draining wetlands, _________ by livestock, flood control, water ________, lowering water tables, and invasion by non-native __________.

Biophilia

Our sense of connection to nature and all life.

Medicinal

There are many practical benefits to species diversity like ___________ uses of organisms, foods, and fibers for human uses We also lose genetic variation and certain genes and proteins that science uses for genetic engineering. ,

Ecosystem Services

All the processes through which natural ecosystems help sustain human life. Purify water and air, detoxify and decompose wastes, reduce impacts of extreme weather and flooding etc.

Habitat destruction, Invasive species, Population growth, Pollution, Climate change, and Overexploitation

HIPPCO is an acronym used to describe the major threats to biodiversity and ecosystems. What does it stand for?

Habitat Destruction

The single greatest threat to biodiversity throughout the biosphere. Brought about through agriculture, urban development, forestry, mining, and pollution.

Habitat Fragmentation.

When an original expanse of a habitat is broken into “islands” of the original habitat dispersed throughout a changed area. Leads to species loss because smaller populations have a higher probability of local extinction.

Introduced Species

Non-native or exotic species that humans move intentionally or accidentally from the species native location to new geographic locations. These species are free from their natural predators, parasites, and pathogens of their native habitat and therefore often outcompete other species and disrupt the community.

Overharvesting

The harvesting of wild organisms at rates exceeding the ability of their populations to rebound. Species with restricted habitats are particularly vulnerable as well as large organisms with low reproductive rates.

DNA

Scientists can use the _________ in tissues of endangered animals to track where they were killed.

Global Changes

The fourth threat to biodiversity, the alteration of earth’s ecosystems at regional to global scales. Includes climate change, atmospheric chemistry, and broad ecological systems that reduce the capacity of Earth to sustain life.

Acid Precipitation

Rain, snow, sleet, or fog with a pH less than 5.2/ Caused by the burning of wood and fossil fuels which release oxides of sulfur and nitrogen that react with water in the air forming sulfuric and nitric acids. These acids fall to earth and harm ecosystems and organisms.

Small

______ populations are particularly vulnerable to over harvesting, habitat loss, and other threats to biodiversity. A small population can push itself to extinction due to lack of genetic variety or inability to rebound from events that cause a drop in numbers.

Extinction Vortex

A downward population spiral in which inbreeding and genetic drift combine to cause a small population to shrink and unless the spiral is reversed, become extinct.

Variation

Small populations are subject to a loss of genetic ___________ which is very harmful because individuals are more likely to be homozygous for harmful traits or not have resistance genes.

Minimum Viable Population (MVP)

The smallest population size at which a species is able to sustain its numbers and survive. Usually estimated using computer models.

Effective Population Size

An estimate of the size of a population based on the numbers of females and males that successfully breed; generally smaller than the total population.

Ne= (4NfNm)/ Nf+Nm

Formula for effective population size (Ne)

Reproductively Active

When considering minimum Viable number of a species or population it is best to consider _______ ________ individuals.

Declining Population approach

The approach to conservation ecology that focuses on threatened and endangered populations which down a downward trend even if the pop[ulation is far above minimum viable population.

Small; declining

The ______ population approach emphasizes smallness itself as the issue while the ________ population approach emphasizes the environmental factors that caused a population decline in the first place.

Conflicts

Conservation biology and its efforts to preserve diversity often face _______ of interest like job opportunities and human needs/safety.

Keystone

Not every species can be saved but _______ species should be prioritized to maintain higher levels of biodiversity as a whole.

Structure

The physical features of a given landscape; heavily influences biodiversity especially for species that use more than one kind of ecosystem.

Boundaries

The ______________ between ecosystems are defining features of landscapes and often have their own physical conditions which are an intermediate of the two ecosystems.

Edges

Human alterations and habitat fragmentation can lead to an increase in “_______” between ecosystems which can lead to a decrease in biodiversity and the preponderance of edge-adapted species.

Movement Corridor

A narrow strip or series of small clumps of habitat connecting otherwise isolated patches which can help to conserve biodiversity. A series of small clumps or a narrow strip of quality habitat that connects otherwise isolated patches of habitat. They also promote disperals and reduce inbreeding in declining populations.

7%

About _____ of the world’s land has been set aside in various forms of reserves.

Biodiversity Hot Spot

A relatively small area with numerous endemic species and a large number of endangered and threatened species. Areas that take high conservation priority.

Endemic Species

A species that is found nowhere else in the world.

Disturbances

Management policies of reserves must balance between ignoring management of natural _______ and stopping them all together as a moderate amount promotes diversity and ecosystem health overall.

Small, large

______ , unconnected reserves can be helpful in slowing the spread of disease however _________ reserves are less affected by edges and have a greater range of species with extensive habitats. Overall, scientists have found reserves are too small.

Zoned Reserve

An extensive region that includes areas relatively undisturbed by humans surrounded by areas that have been changed by human activity and are used for economic gain. The surrounding areas continue to support human activities but regulations prevent extensive alterations likely to harm the protected area and therefore these surrounding areas act like buffer zones.

Marine

Efforts have been made to establish more _______ reserves to combat overfishing and human damage. Some marine sanctuaries have already been put in place and have seen great success.

Nutrient Enrichment

Human activity often leads to nutrient displacement and a disruption of natural chemical cycling. This can lead to ________ ___________ where nutrients are increased in one area and depleted in another and in both the chemical cycles are disturbed.

Nitrogen

One example of nutrient enrichment is seen with the chemical ________ which is often displaced by farming where crops containing it are exported but fertilizers add it back in high amounts and a leached to water sources and other ecosystems.

Critical Load

The amount of a nutrient that can be absorbed by plants without damaging the ecosystem integrity. When this has been exceeded disruption occurs.

Rivers

Concentrations of chemicals often accumulate in lakes or _______ due to run-off or leaching which can lead to eutrophication or depleted oxygen levels.

Toxins

Humans release an immense amount of ________ into the biosphere where they can accumulate in or affect organisms.

Biological Magnification

A process in which retained substances (like toxins) become more concentrated at each higher trophic level in a food chain. This occurs because the biomass at any given trophic level is produced from a larger biomass ingested from the level below.

Top-level carnivores

Which level of a food chain/pyramid would be most affected by toxic co,pounds in the environment.

Chlorinated Hydrocarbons

a class of industrially synthesized compounds that have demonstrated biological magnification. Includes the industrial chemicals called PCBs (polychlorinated biphenyls) and many pesticides, such as DDT.

DDT

A chemical used to control insects such as mosquitoes and agricultural pests that decimated the populations of birds that feed at the top of food webs and has since been banned.

Climate change

A directional change to the global climate that lasts for three decades or more.

Carbon Dioxide

Human actions contribute to climate change because the burning of fossil fuels has drastically increased the amount of __________ in the atmosphere.

Greenhouse Gases

Atmospheric gases that intercept and absorb much of the infrared radiation that Earth emits radiating most of it back toward Earth. Includes CO2, Methane, and Water Vapor

Greenhouse Effect

The warming of Earth due to the atmospheric accumulation of carbon dioxide and certain other gases which absorb reflected infrared radiation and reradiated some of it back toward Earth.

Increase

As global temperatures ________, climate also changes through wind and precipitation patterns and more common extreme weather events

Range

Global warming affects the geographic _______ of organisms which may not be able to adapt or move fast enough.

North

The habitats that have been the most affected by climate change are the farthest __________. Some acrtic regions have even been switched from a CO2 sink to a CO2 source

Fires

Warmer drier temperatures as a result of climate change can also increased the risk of _________.

Many approaches are needed to slow climate change. Everyone can help by using energy more efficiently but things like replacing fossil fuels with renewable solar and wind power and, more controversially, with nuclear power may require national and international support and regulations. Another important approach is slowing ___________ around the world to allow for reabsoprtion of carbon dioxide and cut down on emissions.

Human Population

Global environmental problems, such as climate change, arise from the intersection of two factors. One is the growing amount of goods and resources that each of us consumes. The other is the increasing size of the _________ ________, which has grown at an unprecedented rate in the last few centuries.

Industrialization

Today, the growth rates of individual nations tend to vary with their degree of _________. With industrialized nations having populations near equilibrium or even below replacement and less industrialized nations having the most population growth.

10-15 billion

Average estimates for human carrying capacity average around _______________

Ecological Footprint

The aggregate land and water area required by a person, city, or nation to produce all of the resources it consumes and to absorb all of the waste it generates. Found by adding up all of the ecologically productive land on the planet and dividing it by the population. Each person should have a footprint of 1.7 gha

Sustainable

Ecologists try to find solutions that are _____________ when establishing long-term priorities.

Sustainable Development

Economic development that meets the needs of people today without limiting the ability of future generations to meet their needs. Efforts are needed from individuals, businesses, fields, countries, and international support. Takes a collective and interdisciplinary approach.

Low

If a population has reduced heterozygosity, increased homozygosity, genetic drift, and inbreeding the effective population size is likely ______.

Habitat Destruction

Greatest threat to biodiversity is______________________

United State

Organisms introduced into the _________ _________ that are invasive:

Kudzu, zebra mussels, starling, brown tree snake

Edge species

Species that may require the conditions of both bordering habitat types.

Solar, nuclear, geothermal

Switching from fossil fuels to _____ energy would significantly decrease the release of carbon dioxide into the atmosphere.

Ozone Depletion

Gradual thinning of the Earth’s ozone layer. This is harmful to humans and other organisms because ozone protects from UV radiation and without a strong layer organisms are exposed to high amounts of UV.

Ozone Depleting Substances

Bromine and chlorine containing chemicals; chlorofluorocarbons, carbon tetrachloride, methyl bromide, hydrochlorofluorocarbons. Some of these chemicals used to be involved with the functioning of refrigerators but have now been banned/reduced.