ENV 1301 Exam 2 Notes

What does the IPAT model represent?

total impact (I) on the environment results from the interaction of population (P), affluence (A), and technology (T0

What is demography?

Principles of population ecology can be applied to the study of stat changes in the human population

What human population characteristics do demographers study?

Size, density, distribution, age structure, sex ratio, rates of birth, death, emigration, and immigration

What is the total fertility rate (TFR)?

average number of children born per woman during her lifetime

What is Replacement fertility

the TFR that keeps the size of the population stable. 2.1

what is the rate of natural increase?

includes only birth and death rates

What is Malnutrition?

shortage of specific nutrients, such as lipids, proteins, vitamins, or minerals

What is Kwashiorkor?

causes bloating of the abdomen, deterioration of hair, mental disability, and other issues

What can lead to Marasmus?

protein deficiency and a loss of calories

What leads to anemia?

deficiency of iron

What is traditional agriculture?

the work of cultivating, harvesting and distributing crops was performed by human and animal muscle power

What are polycultures?

Something that most farmers plant, mixtures of different crops in small plots of land

What is industrial agriculture?

introduced large scale mechanization and fossil fuel consumption into agriculture

What are monocultures?

where farmers grow vast areas of single crops in orderly rows

What was the Green Revolution?

introduced new technology, crop varieties, and farming practices to the developing world

What is sustainable agriculture?

maintains healthy soil, clean water, pollinators, and other vital resources

what are some economic and societal factors that affect fertility?

Access to contraceptives, acceptance of contraceptive use, level of women’s rights, cultural influences, level of affluence, importance of child labor, and availability of governmental support for retirees

What is low input agriculture?

an approach that uses less amounts of fossil fuels, water, pesticides, fertilizers, growth hormones, and antibiotics than are used in industrial agriculture

What is soil?

a system consisting of disintegrated rock, organic matter, water, gases, nutrients, and microorganisms

What does weathering do?

Parent material is broken down into smaller particles

What is physical weathering?

results from wind, rain, freezing, and thawing

What is chemical weathering?

occurs as water or gases chemically alter rock

What is biological weathering?

involves living things, such as lichens producing acid or tree roots rubbing against rock

What are soil horizons

the movement and sorting of soil particles creates distinct layers

What is soil profile?

entire cross section of soil

What is leaching?

minerals dissolved or suspended in water can be transported downward in a process

What is topsoil?

a mixture of inorganic mineral components with humus mixed in from above

What is swidden agriculture?

where they culivate a plot for a few years and then move on to another

What is slash and burn agriculture?

a practice where plots are burned first

What is irrigation?

the artificial provision of water beyond what is received by precipitation

What is waterlogging?

occurs when irrigation oversaturate the soil to the point where water drowns plant roots, depriving them grass

What is salinization?

the buildup of salts in surface soil layers as a result of irrigation

What are fertilizers?

substances that contain essential nutrients for plant growth

What are inorganic fertilizers?

fertilizers that are mined or synthetically manufactured

What are organic fertilizers?

fertilizers that are made of the remains or wastes from organisms, including manure, crop residue, charcoal, fresh vegetation and compost

What is compost?

mixture produced when decomposers break down organic matter in a controlled environment

What is precision agriculture?

involves monitoring soil nutrient levels and only applying specific types of fertilizer when needed

What is erosion?

the removal of material from one place and its transport to another by wind or water

What is deposition?

when eroded material is left at a new location

what are drylands?

arid and semi arid environments that cover about 40% of the Earth’s land surface

what is desertification?

a land degradation where more than 10% of productivity is lost

What is overgrazing?

without adequate regeneration of plant biomass

what is a pest?

any organism that damages crops or lievstock

what is a weed?

any plant that competes with crops

What are pesticides

include synthetic chemicals that kill insects (insecticides), plants (herbicides) and fungi (fungicides)

What are biological control/ biocontrol?

An alternative to chemical pesticides. where natural predators or parasites are introduced to eliminate the pest

What is a transgenic organism?

an organism that contains DNA from another species

What is biotechnology?

creates products derived from organisms

What is biodiversity?

the variety of life across all levels of biological organization (genes through ecosystems)

What is a species?

a set of organisms that share unique characteristics and can breed and produce fertile offspring

what is species diversity?

describes the number or variety of species found in a region

What is the Endangered Species Act (ESA of 1973?

offers protection to species that fall within the endangered and threatened. It forbids the US government and citizens from taking actions that destroy individuals within identified species

What is habitat conservation plans?

Allow the landowner to harm some individuals of a species if the overall habitat is improved

What is a safe harbor agreement?

a promise that the government will not pursue additional action if the landowner pursues actions that assist in the species’ recovery

What is the Living Plant Index?

a way to express how large the average population size of a species is now compared to a baseline year of 1970

What is extinction?

occurs when the last member of a species dies and the entire ceases to exist

What is Exirpation?

the loss of a species from one area, but not the entire world

What is the background extinction rate?

the pace at which organisms independently go extinct

What are mass extinction events?

events that eliminated at least half of the species on the Earth

What is the Red List?

list of all species at high risk of extinction

What is habitat fragmentation?

habitat loss most commonly occurs through gradual, piecemeal degradation

What is poaching?

the illegal killing of wildlife for meat or body parts

What is conservation biology?

a study that seeks to understand the loss, protection, and restoration of biological diversity

What is minimum viable population size?

how small a population can become and how much genetic variation it can lose before encountering inbreeding depression

What is the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)?

bans the international transport of the body parts of rare species

What is the Convention on Biological Diversity?

a treaty that provides funding and incentives fro conservation in developing countries

What is captive breeding?

where endangered individuals are bred and raised with the intention of reintroducing their progeny into the wild

What is biodiversity hotspots?

regions that support a large number of species that are found nowhere else

What is a forest?

any ecosystem with a high density of trees

What are forest types?

classifications of forests based on their predominant tree species

What is canopy?

the upper level of leaves and branches in the treetops?

What is a sub canopy?

the middle portion of the forest, found beneath the tree crowns of the canopy

what is the understory?

the shaded lower level consisting of shrubs and small trees

what is the forest floor?

contains ground cover plants

What are snags?

dead and dying trees that are home for insects, which in turn provide food sources for birds

what are tree fall gaps?

Fallen trees create openings, these are areas where sunlight encourages the growth of early successional plants

What is deforestation?

the clearing of forests more quickly than they can regrow

What is the primary forest?

natural forest left uncut by people

What are the secondary forests?

may have a very different species composition, structure, and nutrient balance

What are concessions?

developing nations may allow their timber to be extracted by large multinational corporations, who pay them these fees.

What did Thomas Malthus argue?

That the number of people would eventually outgrow the available food supply

What was The Population Bomb?

Paul and Anne Ehrlich of Stanford University made similar warnings in their 1968 book