BIO Ch. 46
watershed
A _______ is an area from which all precipitation drains into a specific waterway
biomass pyramid; producers; aquatic systems
A _________ depicts dry weight of organisms at each trophic level in an ecosystem Largest tier is usually ______ For some ______, pyramid is inverted
Food chain
A sequence of steps by which some energy captured by primary producers is transferred to organisms at successively higher trophic levels Omnivores feed at several levels
runoff; leaching
Ammonium, nitrite, and nitrate are also lost from land ecosystems in _____ and by _____
energy pyramid; producers
An ________ depicts the energy that enters each trophic level in an ecosystem Largest tier is always _______
Ammonification
Bacteria and fungi make additional ammonium available to plants when they break down nitrogen-rich wastes and remains is called __________
Nitrification
Bacteria convert ammonium to nitrite (NO2-), and then to nitrate, which plants easily take up is called ______
N2O
Chemical fertilizers and manure from livestock increase bacterial production of _____ Burning fossil fuel also releases _____ into the air
sewage, fertilizer run-off, nutrient runoff from the land.
Cultural eutrophication is caused mostly by _____, _____ and increased ______
Denitrification
Denitrifying bacteria convert nitrate or nitrite to gaseous nitrogen (N2) or nitrogen oxide (NO2) is called _______
trophic level
Each _______ is a number of transfers away from the system's original energy input
greatest; aquatic systems
Efficiency of transfers tends to be _____ in ________ (less lignin, more ectotherms)
oxygen; hydrogen; carbon; nitrogen; phosphorus
Elements essential to life (nutrients) include ______, _____, ______, ______, & ________
one way; Producers; photosynthesis; Metabolic; not
Energy flows ______ _____ capture light energy and convert it to bond energy in organic molecules (________) ______ reactions break bonds and give off heat, which is _____ recycled
Detrital food web
Energy in producers flows to decomposers and detritivores, which tend to be small is called _____
Grazing food web
Energy stored in producers flows to herbivores, which tend to be large animals is called ______
shortest; variable; longer; stable
Food chains tend to be _____ in _____ habitats, _____ in ____ habitats
carnivores; fewer; herbivores; more
Food webs with more ______ have _____ connections; _____ have _____ connections
5,000 gigatons
Fossil fuels such as coal, oil, and natural gas hold an estimated _______ of carbon
Consumers (heterotrophs)
Get energy and carbon from organic sources Carnivores, herbivores, parasites, omnivores
Trophic levels
Hierarchy of feeding relationships in which energy is transferred when one organism eats another Each trophic level is a number of transfers away from the system's original energy input
increase; cultural
Human activity can greatly _______ the input of nutrients into the water This is called _____ eutrophication
biogeochemical cycle
In a ________, an essential element moves from nonliving environmental reservoirs, into living organisms, then back to the reservoirs
detritivores
In aquatic ecosystems, most of the energy in producers flows to grazers rather than ______
detrital food chains
In land ecosystems, most of the energy stored in producers moves through ________
carbon cycle; carbon; food webs
In the ________, _______ moves among Earth's atmosphere, oceans, rocks, and soils, and into and out of ________
nitrate; iodine
Ingested ______ inhibits _____ uptake by the thyroid gland and may increase the risk of thyroid cancer
atmospheric cycle
It is an ________ - the atmosphere holds about 760 gigatons (billion tons) of carbon, mainly in the form of carbon dioxide (CO2)
photosynthesis
Land plants incorporate CO2 from the atmosphere into their tissues through _______ Soil contains more than twice as much carbon as the atmosphere - consisting of humus and living soil organisms
calcium; 65 gigatons
Marine sediments and sedimentary rocks formed from _____ carbonate-rich shells are Earth's largest carbon reservoir, with more than ______
ocean; atmosphere
Most of the annual cycling of carbon occurs between the ______ and the _______
cycled; inorganic; decomposers
Nutrients are ______ Producers take up ______ compounds from the environment; ______ return them
inorganic reservoirs; primary producers
Nutrients move from __________ (rocks, sediments, water, atmosphere) to living systems through ________
Primary producers (autotrophs)
Obtain energy from nonliving sources (sunlight) Build organic compounds from CO2 and water
oceans
Oceans cover about 70% of Earth's surface, so most rainfall returns water directly to the _______
marine carbon cycle
Photosynthesis, aerobic respiration, decomposition, and sediments contribute to the ________
CO2 ; aerobic respiration
Plants and other organisms release _____ into the atmosphere through ________
Primary production
Rate at which producers capture and store energy
twice
Soil contains more than _____ as much carbon as the atmosphere - consisting of humus and living soil organisms
heat; not
Some energy is lost as ____ Some biomass is _____ digested
10
The EPA mandates that public drinking water contain less than ____ ppm nitrate and requires periodic testing
water cycle
The _______ moves water moves from the world ocean (main reservoir) through the atmosphere (by evaporation and transpiration), onto land (by condensation and precipitation), then back to the ocean
algae blooms, cyanobacteria, water hyacinths, duck weed
The added nutrients cause _____, large colonies of ______, _______, and ________.
nitrogen cycle; N2; ammonia; ammonium & nitrate
The nitrogen cycle starts with nitrogen fixation Nitrogen-fixing bacteria convert _____ in the air to ______ (NH3), then to _______ (NH4+) and ______ (NO3-), which plants easily take up
fertilizers; fossil fuels
The use of ______ and burning of _______ has added large amounts of nitrogen-containing compounds to our air and water and altered the nitrogen cycle
phosphorus cycle; phosphorus
The_________ is a sedimentary cycle that moves _______ from its main reservoir (Earth's crust) through soils and sediments, to food webs
depletes, aquatic organisms
When they die their decomposition _____ the dissolved oxygen This oxygen depletion causes the death of ______
Chemical; geologic
_____ and ______ processes move elements to, from, and among environmental reservoirs
Cumulative; length of food chains; four; five
_____ energy losses from energy transfers between trophic levels limits the ________ to _____ or _____ trophic levels
N2O; CO2
_____ is a highly persistent and effective greenhouse gas, with a warming potential 300 times that of _____
Community, Biotic
______ - group of interacting populations that inhabit the same region ______ - living organisms
N2O
______ contributes to destruction of the ozone layer which protects life at Earth's surface from damaging UV radiation
Photosynthetic
______ organisms take up dissolved ions and carbon dioxide; bacteria fix nitrogen gas
5 to 30%
_______ % of energy in tissues of organisms at one trophic level ends up in tissues of those at the next trophic level
Bicarbonate; inorganic carbon
_______ (HCO3-) is the main _______ in seawater
Nitrate (NO3-)
_______ from fertilizers and septic tanks leaches into groundwater and contaminates sources of drinking water
Decomposers
_______ such as bacteria and fungi, feed on organic wastes and remains and break them down into inorganic building blocks
Detritivores
_______ such as earthworms and crabs, eat small particles of organic matter (detritus)
Food webs
_______Multiple interconnecting food chains
Groundwater; soil water; aquifers
________ includes ________ and water in ________ (permeable rock layers that hold water)
Gaseous nitrogen (N2); 80; gaseous nitrogen
________ makes up about _____ percent of the lower atmosphere Most organisms can't use _________
Flowing
________ water carries nutrients from place to place
Greenhouse effect
________Radiant energy from the sun is absorbed by Earth's surface and radiated back as heat Gases in the upper atmosphere trap heat like a greenhouse, and radiate it back to Earth
Ecosystem
_________ - includes all the organisms plus abiotic, or nonliving, environment with a defined area
Atmospheric CO2
_________ fluctuates seasonally with patterns of photosynthesis
Greenhouse gases
_________ include carbon dioxide, water, nitrous oxide, methane, chlorofluorocarbons (CFCs)
Global climate change
_________ is a long-term alteration of Earth's climate - global warming is one aspect of this change
Runoff
_________ is water that flows over saturated ground into streams
Gross primary production; Net primary production
__________ - amount captured by producers ________ - amount used in growth and reproduction
Primary producers
__________ capture energy and take up nutrients, which move to other trophic levels
Phosphorus; phosphate; phosphorus
__________ is a component of all nucleic acids and phospholipids Land plants take up dissolved ______ from the soil water Land animals get _____ by eating the plants or one another In the seas, ____ enters food webs when producers take up phosphate dissolved in seawater
Eutrophication
is the natural nutrient enrichment of lakes