Test #3 Flashcards
Topic 1: Threats to Biodiversity
cards 2-12
Genetic diversity
variety of genes/inheritable traits in a population
Species diversity
variety of different organisms in an area
Ecosystem diversity
variety of different ecosystems in an area
- regions closer to equator have more eco diversity
Habitat loss
organisms’ area of living gets destroyed/disrupted
Fragmentation of habitat
sep. of an ecosystem into small pieces of land
- edge effect: diff enviro conditions occurring along ecosystems’ boundaries
- natural corridors: pathways connecting segments of habitat
Pollution
accumulation of chemicals in the biosphere
- biological magnification, acid precipitation, eutrophication
Biological magnification
increased concentration of a chemical in organisms
Acid precipitation
fossil fuels are burned- chemicals and smoke go into the atmosphere
Eutrophication
excess nitrogen and phosphorus enter the water- diff nutrients are possible
Introduced/Invasive species
introduced- organisms brought into area they don’t normally grow in
- reproduce rapidly & often take over areas
invasive- out of control species
Biological augmentation
adding a native organism to speed up habitat restoration
- often used to alleviate invasive species
Topic 2: Eutrophication
cards 14-18
Biological Oxygen Demand (B.O.D.)
amount of oxygen needed by the decomposers to break down organic waste in the ecosystem
Dissolved Oxygen (D.O.)
amount of oxygen available to living aquatic organisms
Oligotrophic (lake)
healthy lake
- light penetrates through
- plant and animal biodiversity
- available dissolved oxygen (& low B.O.D.)
- water clarity
Phosphates and nitrates
plant nutrients introduced into lakes that increase plant growth
Algae
plant- if there’s too much- stops light penetration
Topic 3: Environmental Conservation
cards 20-32
Overharvesting/Deforestation
removal of trees faster than forests can replace themselves; usually for wide areas
- solution: replanting
- consequence: monoculture forestry
Monoculture
little biodiversity & poor provision of services: soil erosion control, clean water production
Reducing Emissions from Deforestation and Forest Degradation (REDD)
framework made by the UN framework convention on CC
- purpose is to: reduce emissions from deforestation, reduce forest degradation, manage forests w/ indigenous partnerships
Clear-cutting
process of cutting down all the trees in an area at once
Strip cutting
loggers cut down trees in narrow strips that are left to reseed
Selective logging/cutting
cutting down only some trees in a forest and leaving a mix of tree sizes and species behind
Shelterwood harvesting
mature trees are removed in a series of two or more cuts
Problem- overgrazing
precip run offs- causes accelerated erosion rather than being absorbed by soil
- plants undernourished (disrupts food webs)
- groundwater not replaced
- leads to desertification- converts fertile land to
desert
2 overgrazing solutions
- Rotational Grazing- confine animals to a small area for 1-2 days before relocating them
- Raise Wild Species- take less care & supplements, uses greater plant types more efficiently
Parks and preserves in nations have different
levels of protection for diff preserves
- %s & management level varies between nations
International Union for Conservation of Nature (IUCN) strategy
- maintain essential eco processes
- preserve genetic diversity
- ensure sustainable use
Ecotourism
activities of people traveling structured to be eco and socially sustainable
Biosphere reserves
protected areas divided into zones with different purposes
Topic 4: Food and Agriculture
cards 34-61
Global trends
- large % of food comes from large-scale agriculture
- probs w/ insufficient quantities of food/calories
- probs w/ nutrition/vitamin deficiency & overeating
Food innovation
- confined animal feeding operations
- new breeds
- special feed, antibiotics
Water and wind erosion
detachment & removal of soil by water/wind
- row crops, lack of weeds, lack of wind/water breaks expose more soil
Nutrient depletion
usually occurs w/ removal of topsoil
Salt accumulation
occurs when the water reaching is just enough for plant growth
Causes of soil degradation
acidification, pollution, soil compaction, waterlogging, laterization
Acidification
from acid rain, parent bedrock, mineral leaching, high crop yields
Soil compaction
from heavy equipment
Waterlogging
saturation of soil with water
- from excess irrigation
Laterization
solidification of soil in tropical climates due to exposure to sun and rain
Water wastage
- areas of high evaporation
- unlined irrigation equipment
soil effects: waterlogging and salinization (has high salt content)
Fertilizer usually has
nitrogen, phosphorus, & potassium
Overfertilizing
leads to polluted runoff or adding to groundwater
- manure is an alternative to inorganic fertilizer
- incorporating legume (bean/peanut) helps w/ nitro
Oil uses
- tractors & other machinery
- transportation
- makes fertilizer & pesticides
- runs irrigation pumps
- dries and processes crops
Oil use results in
increasing greenhouse gases
- carbon dioxide: use of fossil fuels
- methane: livestock & bacteria in wet rice paddies
- nitrous oxide: from ammonia fertilizers
Goal of pesticides is to
eliminate pests & increase crop yields
Pesticide problems
- may contaminate water
- could cause biological magnification
- pesticide treadmill: increasingly complex mixture of pesticides in response to pest resistance
Pesticide alternatives
- mixing crops/crop rotation
- cover crops
- polyculture
- biological augmentation
- genetically modified organisms (GMOs)
Crop rotation/mixing crops
prevents animal populations from growing
Cover crops
controls the organisms that colonize
Polycultures
planting them prevents population growth in ideal conditions
Biological augmentation
adding a native organism to speed up habitat restoration
Genetically modified organisms (GMOs)
- most engineered for pesticide production/tolerance
- concern about ecological effects if it escapes captivity & unknown effects on economy/social constructs
Sustainable farming
- soil conservation (terracing, contour, strip-farming)
- leave crop residue or use cover crops
- crop rotation
- nutrient management
Terracing
shaping the land to create shelves of Earth to hold soil and water
Contour
plowing across a hill, not up and down
Strip-farming
planting different kinds of crops in alternating strips along land contours
Action steps
- support local farmers
- eat more grains & vegetables- less meat
Topic 5: Environmental Health and Toxicology
cards 63-92
Study environmental health because
- natural resources are used to support human health
- human actions and enviro issues are interdependent & influence each other
Ecological disease
sudden, widespread epidemics among livestock or wild species
Pandemic vs Epidemic
pandemic = infectious disease spreads around the globe (disease’s growth is exponential)
epidemic = infectious disease spreads rapidly to a large population
Conservation medicine
emerging sci attempting to understand how enviro change threatens human & eco communities
Antibiotic problems
caused by:
- ability to evolve as population
- overuse in people and livestock
- failure to complete treatment
may lead to higher cases of chronic diseases
Toxicology
study of adverse effects of external factors on organism or system
Environmental toxicology
sci that studies interactions, transformation, fate, & effects of toxins in biosphere; includes organism, population, & ecosystem levels
Allergen
substance that activates immune system
Antigen
substance recognized as foreign by white blood cells & stimulate production of specific antibodies
Antibody
protein produced by human bodies that recognize & bind to foreign cells or chemicals
Neurotoxin
special class of metabolic poisons that specifically attack nerve cells (neurons)
Mutagen
agents that damage or alter genetic material (DNA) in cells
Teratogen
chemical/other factors that specifically cause abnormalities during embryonic development
Carcinogen
substance that causes cancer
Endocrine hormone disruptor
chemicals that interrupt normal endocrine hormone functions
Toxin behavior
chemical move between organisms & eco based on molecular size, solubility, stability, & reactivity
Solubility
physical property that indicates how easily substance dissolves in another substance
Soluble types
water- move rapidly & widely through enviro
fat (more toxic)- usually has carrier to navigate enviro, once inside organism, penetrates tissues & accumulates
Stability
- exposure to sun, air, & water may break down/inactivate a substance
- more persistent materials last years/centuries cycling through ecosystems
Reactivity
could be antagonistic reactions, additive effects, and/or synergism
Antagonistic reaction
interferes with effects of/breakdown of other chemicals
Additive effect
effect of multiple substances increases in proportion to the exposure
Synergism
interaction where 1 substance exacerbates effects of another- effects increases disproportionately
Ways toxins can enter human bodies
- inhalation
- dermal (skin) absorption
- oral (food, water, medicine)
- injection (IV, intramuscular)
varies depending on: age, health, time, & route of exposure
Dose
quantity usually reported as a concentration
Lethal dose
substance amount exposed to at one time that kills 50% of population
Retrospective study
identifies people exposed and compares health to a control group
Prospective study
identifies people & DOCUMENTS potential exposures and health effects
Animal study
- specific studies required based on intended use
- requires 2 animal models: rodent & non-rodent
Biomagnification
increase in concentration of a substance in successively higher trophic levels
