APES MIDTERM

Carbon Cycle

The organic circulation of carbon from the atmosphere into organisms and back again

sink

a reservoir that stores more than it releases

source

a process that adds more than it reserves

photosynthesis

Plants use the sun's energy to convert water and carbon dioxide into sugars
key process in the carbon cycle

cellular respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
key process in the carbon cycle

direct exchange

CO2 moves directly between atmosphere and the ocean by dissolving into and out of ocean water at the surface

sedimentation

the action or process of forming or depositing sediment
process in the carbon cycle where marine organism bodies sink to the ocean floor and broken down into carbon sediments

burial

step in the carbon cycle where the long time pressure of water compresses carbon into sedimentary stone

Nitrogen cycle

The transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere

reservoir

the atmosphere is the biggest nitrogen ______________

nitrogen fixation

Process of converting nitrogen gas into ammonia (usable form of nitrogen)

bacterial nitrogen fixation

Process by which certain bacteria living in soil convert nitrogen gas (N2) to ammonia (NH3).

synthetic nitrogen fixation

humans combust fossil fuels to convert N2 gas into nitrate (NO3)

Nitrogen cycle steps

nitrogen fixation, nitrification, assimilation, ammonification, denitrification

assimilation

part of the biogeochemical cycles (especially of nitrogen and phosphorous) where plants and animals take in nutrients and other chemicals

ammonification

soil bacteria, microbes, decomposers convert waste and biomass back into NH3 and return it to the soil

nitrification

ammonia is converted to nitrate ions by soil bacteria

denitrification

Conversion of nitrates into nitrogen gas which returns to the atmosphere

ammonia volatilization

excess fertilizer use can lead to NH3 gas entering the atmosphere
causes acid rain and respiratory irritants

eutrophication

A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.

phosphorous cycle

the cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment
SLOW CYCLE
NO GAS PHASE (no phosphorous cycle in the atm)

phosphorous used in all organisms in DNA, ATP, bone and tooth enamel, etc

natural phosphorous sources

weathering of phosphorous containing rock that is broken down by the wind, where phosphorous is released and dissolved, rain carries phosphorous in soil

synthetic phosphorous sources

humans mine phosphorous rocks and adds phosphorous to fertilizers/detergents/cleaners --> often leads to phosphorous being carried out as waste

steps of the phosphorous cycle

Phosphate released by erosion of rock
Plants take up the phosphate (assimilation)) Phosphorus moves from producer to consumer
excretion
phosphorus seeps into groundwater from soil, forming rocks (sedimentation)
Rocks erode (geo uplift), cycle goes on

excretion

part of biogeochemical cycles where chemicals are excreted through waste and biomass is broken down to return/continue the cycle

geological uplift

exposing underground rocks to the surface
(part of the phosphorous cycle)

the deadzone

a location within a body of water that does not have enough dissolved oxygen to sustain life.

(often occurs from eutrophication)

Hydrologic cycle

the movement of water through the biosphere
DRIVEN BY THE SUN --> phase changes

water reservoirs

the ocean is the largest water ______________
smaller __________________ include icecaps and groundwater

evaporation

The change of a substance from a liquid to a gas

transpiration

Evaporation of water from the leaves of a plant

evapotranspiration

the amount of water that enters the atm. from transpiration and evaporation

runoff

water that flows over the ground surface rather than soaking into the ground

infiltration

the process by which water on the ground surface enters the soil

groundwater aquifers

water held within the spaces in porous, permeable rocks

components of soil

sand, silt, clay, humus, nutrients, water, air, living org

purpose of soil

anchors plants to the ground, filters rainwater, recycles nutrient, provides habitat

weathering

The physical (wind and rain), biological (tree roots), and chemical (acid) breaking down of rocks and other materials on the Earth's surface.

erosion

Processes by which rock, sand, and soil that have been broken down/weathered are carried away

deposition

Process in which sediment is laid down in new locations and deposited

soil formation

________ formation
the weathering of parent material to produce sand, silt, clay
the breakdown of organic matter to develop humus

soil horizons

distinct layers of soil

O horizon

The organic horizon at the surface/top of many soils, composed of organic material that traps moisture and provides nutrients

A Horizon

the topsoil that has layers of humus and minerals that has the MOST BIOLOGICAL ACTIVITY. This is the layer of soil where nutrients are released

B Horizon

A soil horizon (subsoil) composed primarily of mineral material with very little organic matter

C Horizon

The least-weathered soil horizon, which is similar to the parent material.

soil degradation

The loss of some or all of a soil's ability to support plant growth
can occur from loss of topsoil, compaction, or nutrient depletion

tilling

The turning-over of soil before planting; contributes negatively to soil quality by disrupting soil structure, accelerating erosion and runoff

soil texture

the percent ratio of sand to silt to clay in the soil

soil porosity

pores or spaces in the soil. The greater pores or spaces, the greater the water holding ability. Sand has the most ___________ and clay has the least. Based on particle size

soil texture chart

Water holding capacity

how well soil can retain water (sand is low, clay is high). Based on porosity , permeability, etc.

soil fertility

A measure of how well soil supports plant growth.

loam

Rich, fertile soil that is made up of about equal parts of clay, sand, and silt.

nutrients in soil

N, P, K+, Mg2+, Ca+, Na+

green revolution

Agricultural revolution that increased production through improved seeds, fertilizers, and irrigation; helped to support rising Asian populations.

mechanization

In agriculture, the replacement of human labor with technology or machines.

High Yield Variety

the development of crops, such as rice, corn, and wheat, specifically bred to replace lower yielding native crops.

synthetic fertilizers

Fertilizer produced commercially, normally with the use of fossil fuels

irrigation

A way of supplying water to an area of land

pesticides

Chemicals used on plants that do not harm the plants, but kill pests and have negative repercussions on other species who ingest the chemicals.
rodenticides, insecticides, herbicides, fungicides

DDT

an insecticide that is also toxic to animals and humans. Led to the thinning of bird shells. Silent Spring book

phthalates

plasticizers used in skin care formulas to moisturize and soften skin, and to dissolve or blend ingredients that are endocrine disruptors

atrazine

Herbicide. Endocrine disruptor that causes the feminization of males, low sperm count.

Monocropping

An agricultural method that utilizes large plantings of a single species or variety. Reduces biodiversity

Slash and burn

A farming method involving the cutting of trees, then burning them to provide ash-enriched soil for the planting of crops

GMO

Genetically modified organism made when DNA is removed from one organism and placed within the DNA of what can be a very different organism.

impact: reduces genetic diversity

Bt crops

crops that have been given a bacterial gene that gives chemical protection against pests

Roundup Ready

Crops that have been modified to withstand treatment with roundup herbicide (glyphosate).

IPM

Pest management using a variety of techniques, agricultural, biological and use of minimal amount of pesticides when necessary. Unfortunately more expensive than pesticides

Biocontrol

Use of one kind of organism that is a predator or parasite of a pest species in order to reduce or eliminate populations of the pest. For example, bringing natural predators, competitors, or parasites to control pests

Crop rotation

The practice of rotating use of different fields from crop to crop each year, to avoid exhausting the soil and allowing pests to lay their eggs and breed there

Intercropping "Push - Pull" system

a agricultural system where pests are pushed out and pulled somewhere else nearby the crops

endocrine disruptors

chemicals that interfere with the normal functioning of hormones in an animal's body

mercury

an endocrine disruptor made in coal burning, medical waste burning, limestone production for cement, and attaches to PM and is deposited. Inhibits estrogen and insulin

teratogen

agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal development and cause harm

Arsenic

an endocrine disruptor that is from rocks underground that dissolves easily in water. Used in pesticides, wood treatments, coal combustion, ash. It is a carcinogen

Lead

endocrine disruptor found in paint, old water pipes, soils, contaminated by PM from old vehicle exhaust. It is a neurotoxicant

coal ash

waste from coal mining that contains mercury, arsenic and lead

persistant organic pollutants (POPs)

compound with carbon in it that resists photochemical, biological and chemical degradation
long-lasting carbon based pollutants that do not easily break down (are stored in animal fat)
they travel with the wind and impact far away ecosystems
in wastewater, leachate, fertilizers, biomass, etc. and are often eaten by animals or enter soil and water

Tragedy of the Commons

situation in which people acting individually and in their own interest use up commonly available but limited resources, creating disaster for the entire community
overusing public/shared resources since they don't experience the negative consequences of doing so (acting in self interest)

Clean Water Act

(CWA, 1972) set maximum permissible amounts of water pollutants that can be discharged into waterways; aims to make surface waters swimmable and fishable

Clean Air act

(CAA, 1970) set emission standards for cars and limits for release of air pollutants
6 Air pollutants
- SO2
- NOx
- CO
- Pb
- PM
- O3

air pollutants

specific chemicals, compounds, or particles harmful to air

air pollution

the introduction of harmful pollutants into atmosphere

SO2 (Sulfur Dioxide)

a pollutant from coal combustion
a respiratory irritant
causes acid rain

Reducing SOx and NOx

Reducing ______ and _____ (air pollutants)
- crushed limestone
- fluidized bed combustion

Crushed limestone

used to reduce SO2 from coal power plants
calcium carbonate + SO2 = calcium sulfate (rather than SO2)

Fluidized bed combustion

a clean-coal technology in which crushed coal is mixed with limestone to neutralize the acidic sulfur compounds produced during combustion
fluidized jets of air are pumped into the combustion "bed"
efficient combustion
brings SO2 into more contact with limestone
less NOx

NOx (Nitrogen Oxides)

pollutant occurs from fossil fuel combustion (gas)
causes smog and acid rain by creating O3

health impact:
- causes ozone formation
- respiratory irritant
- can form nitric acid and acid rain when combined with water and O2

CO (Carbon monoxide)

pollutant from incomplete combustion of fuel source (either from a lack of O2 or lack of temperature)
displaces O2 in the blood -- lethal

impacts:
causes suffocation
binds with hemoglobin in red blood cells
lethal in high concentration
oderless, colorless, and hard to detect

Pb (Lead)

a pollutant from metal plants and waste incineration
in 1978 the EPA prohibited its use in paint

impacts:
nuerotoxicant
damages nervous system

O3 (ozone)

a pollutant that causes photochemical oxidation and photochemical smog
respiratory irritant
causes plant damage

PM (particulate matter)

a pollutant from suspended particles -- common indoors
occurs from combustion, fire, construction, smoke

impacts:
respiratory irritant
causes smog

Electrostatic Precipitator

A device used for removing particulates from smokestack emissions. The charged particles are attracted to an oppositely charged metal plate, where they are precipitated out of the air.

Reduces PM

baghouse filter

Dirty air enters, combustion exhaust stream moes through and dust particles are trapped in a series of filter bags, cleaner and filtered air moves out of unit, shaker mechanism activated periodically to dislodge trapped particles which can then be collected from below unit.

reduces PM

VOCs (Volatile Organic Compounds)

chemical pollutants used in home
products that easily vaporize
ex. adhesives, formaldehydes
carcinogens
ex. plastics and fabrics

impacts:
irritate the eyes and lungs

asbestos

A long, thin, fibrous silicate mineral with insulating properties (no longer used but may be present in older architecture), which can cause cancer when inhaled.
can enter the air and the respiratory track

mesothelioma

lung cancer

Radon Gas

Radioactive gas from uranium decay
can leak into houses through cracks in the ground

impacts:
2nd leading cause of cancer