Enviromental Test 1
Terms
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- Ecological Organization
- organism, population, community, ecosystem, landscape, biosphere
- 1st law of thermodynamics
- energy can neither be created nor destroyed but can change forms
- 4 types of energy
- kinetic, potential, heat, solar
- 2nd law of thermodynamics
- with every energy transformation, there is a loss in usable energy
- entropy
- all energy is moving toward a less availablt and more dispersed state
- Ecosystem composition
- producers, consumers, decomposers
- consumers
- herbivores, detrivores, omnivores, carnivores
- Biogeochemical cycles
- hydologic, nitrogen, phosphorous, carbon
- list the 5 biomes
- tundra, boreal forest, tropical rainforest, desert, temperate grassland
- describe the tundra
- v. high latitudes, nutrient poor soils, low precipitation, treeless, permafrost
- describe the boreal forest
- just south of the tundra, northern coniferous forest, extreme cold winters, little precipitation, some permafrost, acidic, mineral poor soil
- describe tropical rainforest
- lot of rainfall, central and S. America, SE Asia, Africa, warm temperatures, mineral poor
- describe Temperate grasslands
- U.S. prairies, hot summers, cold winters, mineral rich topsoil, periodic wildfires
- Desert
- major temp. changes, little organic material in soil, temperate, subtropical
- what 3 things erode land mass?
- wind, precipitation, temp. changes
- definition of ecological succession
- the gradual changes over time in dominant species within a community following an ecological disturbance
- what is primary succession
- occurs in uninhabited area, starts with nothing, pioneer communities move in, soil forms, lichens-moss-grass-shrubs-trees
- secondary succession
- start with something( re-establish) area degraded ie burned forest faster than primary
- describe an S-curve
- upper limit of curve indicates pt. at which birth and death rates are in equilibrium between the biotic potential and environmental resistance
- describe a J-curve
- population growth exponentially increases up to or beyond carrying capacity--population crash
- population definition
- collective individuals of the same species living together within a given area
- biotic potential definition
- the max. growth rate that a population can achieve in an unlimited environment.
- environmental resistance definition
- the environmental pressures that limit the populations capacity for growth
- homeostatic controls
- behavioral, physiological, and social responses that control population size
- list some homeostatic controls
- food shortage disease excess predation overcrowding stress
- Factors affecting birth rates
- nutrition, education for mother, career opportunities for women, value of children, contraception availability
- factors affecting death rates
- nutrition medical care disease age structure infant mortalities
- Density efficient for:
- utilities, sanitation, transportation, goods+services
- too much puts pressure on:
- resources, sanitation, health care, psychological stress
- pregnancy after age 35 increases risk of:
- LBW, miscarriage, premie, stillborn
- factors influencing food demands
- population growth, rising increase in personal incomes= increased demand of high quality foods
- basal metabolic rate
- minimum amount of energy needed to power the human body
- causes of famine:
- prolonged droughts, floods, wars
- causes of hunger
- unequal food distribution, poverty, rising food prices
- Mediterranean diet
- some meat, veggies, pasta, seafood
- Kwahiorkor
- protein deficiency symptoms: hair loss, bloated stomach, muscle wastage, discoloration of hair, white patches on skin, loss of appetite, digestion problems, enlarged liver
- Marasmus
- overall protein calorie deprevation starvation, often occurs after disease or diarrhea, thin, wasted appearance, shrunken body
- Health impact of hunger
- directly impacts mental development and physical growth, increased susceptibility to disease, mothers have high risk of miscarriage, premie, LBW
- Name 3 micronutrient deficiencies
- Vitamin A deficiency Iodine deficiency Iron deficiency
- describe vitamin a deficiency
- cause of childhood blindness 100-140 million affected 250,00-500,000 go blind
- iron deficiency
- anemia most common deficiency 4-5 billion
- Iodine deficiency
- affects 740 million affects fetus wordls #1 preventable cause of mental retardation and brain damage
- Ways to reduce world hunger
- decrease post harvest food loss increase yield per acre expand amount of cultivated land increase world fish catch eat lower on the chain
- what is the #1 cause of soil degradation?
- overgrazing
- what is the T-value
- max. avg. soil loss that will still allow economical maintenance of current level of production in the future
- the Dust Bowl sparked what env. group?
- Soil Conservation Service
- increase in commodity prices and overseas demand in the 1970's increased what?
- reacceleration of soil loss
- What are the 4 types of till?
- conservation till mulch till strip till no till
- describe conservation till
- 30 % or more of soil surface is covered with previous crops residue
- describe mulch till
- entire field is tilled before planting, with crop residue partially incorporated into soil
- describe stip till
- fields are tilled only in narrow raised rows to be planted, remiander left with residue
- describe no till
- crops are planted on undisturbed residue of the former crop with no tilling
- what did the Food Security Act of 1985 do?
- created the Conservation Reserve Program rewarded farmers for leaving certain land for 10-15 yrs grassy areas at low areas
- Causes of soil erosion
- improper mechanical tillage poor water management of irrigate fields water logging, salinization
- Forests cover what percentage of the earths land?
- 30%
- Causes of deforestation
- #1-land clearing for agriculture gathering of fuel wood commercial lumbering cattle ranching soy bean production
- Desertification definition
- land degradation in arid, semiarid, and dry sub-humid areas resulting from climatic variations and human activities
- what is the #1 risk to biodiversity?
- habitat destruction due to human encrochment