Ch: 10 - Systems & Cycles

collection of components interacting with each other to produce outcomes that each component could not achieve on its own

system

system that is affected by outside influences

open system

system that is self-contained, neither receiving inputs nor sending outputs beyond the system’s borders

closed system

outcome arising from the function of the system as a whole

emergent property

supply of something that we want to observe and measure over time

stock

mechanisms and rates by which a stock changes over time

flows

increase the stock 

inflows

decrease the stock

outflows

simplified concept or representation of a complex process that is designed to help understand interactions among different factors

model

supply of something that we want to observe and measure over time

stock

mechanism and rate by which a stock in a system changes over time

flow

series of chemical reactions involving water and CO2 through which plants and some other organisms store the sun’s energy in simple sugars

photosynthesis

loop in a system that responds to and produces changes in levels of stocks that either amplify or counter a change

feedback

loop that responds to the direction of change in the stock by enhancing the same direction of change

reinforcing feedback

type of feedback that counteracts the direction in which a particular stock is changing 

balancing feedback

identifying the complete path of a particular element that returns where it beigns

cycle

path that shows how matter on earth flows through different parts of the environment

biogeochemical cycle

element that organism use in large amounts

macronutrient

place where matter accumulates and is held for a long period of time

sink

free nitrogen

highly stable, nonreactive form of nitrogen that is biologically unusual to humans and most other organism 

nitrogen-fixing symbiotic bacteria that live within a plant without causing harm of disease

diazotrophic endophytes

ammonia from synthetic fertilizers that become airborne linked to a range of human lung problems

fine particulate matter

process where free nitrogen inert nitrogen gas (N2) in the air is converted to soluble ammonium (NH4+) and nitrate (NO3-) ions that plants, algae, and bacteria can take in and use

nitrogen fixation

bacterium with an enzyme that uses free nitrogen from the air along with hydrogen to produce ammonia

diazotroph

process where bacteria and fungi break down nitrogen compounds in animal waste products and in dead plant and animal matter release ammonia

ammonification

process in which microorganism convert ammonia nitrogen compounds

nitrification

process in which microorganism use nitrogen compounds for respiration and create N2 gas, returning it to the atmosphere

denitrification

methane-producing microorganism that thrives in oxygen-poor enviroments

methanogen

ongoing decrease in the pH of earth’s oceans caused by absorption of carbon dioxide (CO2) from the atmosphere

ocean acidification

earth is generally what kind of system for matter?

closed system

earth is generally what kind of system for energy?

open system

oxygen and phosphorus are considered…

macronutrients

process where phosphorus can alter marine and freshwater ecosystems

eutrophication

what percent of nitrogen makes up earth’s atmosphere? 

80%

processes that create more carbon than they sequester

sources