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Freshwater Biology-Chemical Cycles in Water_Cooper
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Gravity
Terms in this set (51)
Biogeochemistry
This refers to the concept of global cycling of chemicals through the biotic and abiotic reservoirs
Water cycle
Water vapor transpires through pores in leaves
Respiration also produces water vapor
Water evaporates from lakes, oceans, and rivers
Water vapor accumulates in the atmosphere and returns to the land as precipitation
What chemical cycles are within ecosystems?
Water
Carbon
Nitrogen
Phosphorous
Carbon cycle
Carbon dioxide
Dissolved Inorganic carbon (DIC)
Dissolved Organic Carbon (DOC)
Particulate Organic Carbon (POC)
Carbon dioxide
Diffuses between water and atmospheric air
Dissolved Inorganic Carbon (DIC)
Carbon dioxide, carbonic acid and bicarbonate ion
Dissolved Organic Carbon
Methane (CH4) is simplest form from decomposition of organic matter
Particulate Organic Carbon
All organic matter: living, dead, waste etc
Carbon Reservoirs
1. Rocks: limestone and dolomite
2. Atmosphere: carbon dioxide 0.04% of air
3. Oceans: bicarbonate ions, about 26mg/L of
organic carbon
4. Freshwater: bicarbonate ions
5. Detritus: bacteria and fine organic matter
decaying
6. Primary Producers: (plants) carbonhydrates
7. Consumers: relatively small amounts
DOC and pH
The CO2, bicarbonate, carbonate forms an equilibrium; whitening of lakes due to precipitation of carbonates
The Dark side of CO2
It can serve as an anesthetic, CO2 eruption in lake Nyos in Cameroun caused death of 1746 people
Oxygen Cycle (forms of oxygen gas)
Oxygen gas
Ozone
Inorganic
Organic
Oxygen gas
Needed for aerobic metabolism
Ozone
Primarily in the upper atmosphere
Inorganic
Component in many inorganic molecules e.g. water, nitrate, phosphate, silicate metal oxides
Organic
Carbon, Hydrogen, and Oxygen are components of all organic molecules.
Oxygen Reservoirs
1. Rocks: mostly bound very tightly to silicon and
aluminum in clay
2. Atmosphere: Diatomic gas (O2) at about 21% in
atmosphere
3. Water: linked to photosynthesis and respiration of plants and animals
Solubility of O2 in water
14mg/L
Define Aerobic respiration?
The process of using glucose and oxygen to produce ATP
Breathing in Water
Gills
Phosphorous Cycle
Total Phosphorous (TP)
Soluble reactive phosphorous (SRP)
Total soluble phosphorous
Orthophosphate
Total Phosphorous
All phosphorous in water sample: 10 to 18 micrograms/liter in most lakes
Soluble reactive phosphorous
Forms readily available for algae and plants
Total soluble phosphorous
All phosphorous that can pass through a filter
Orthophosphate
Inorganic form, nearly insoluble
Forms of phosphorous
1. Dissolved organic phosphorous
2. Particulate organic phosphorous
3. Particulate inorganic phosphorous
4. Phosphine gas
DOP
From living and/or decomposing organisms; also from detergents and some pesticides
POP
Organic phosphorous in plants and animal bodies waste
PIP
Orthophosphate bound to particular matter; electrostatic attraction to clay particles
Phosphine gas
PH3 poisonous gas produced by anaerobic decomposition of organic matter
Phosphorous reservoirs
1. Rocks: abundant in rocks
2. Soil: high in agricultural soils
3. Guano: bird or bat droppings
4. Atmosphere: small amounts in particulates (dust)
5. Oceans: poorly soluble, especially in more
alkaline saltwater, precipitates out to form
sediment layers
6. Freshwater: precipitates out with calcium and
magnesium and clay particles
7. Primary producers: Limiting nutrient for most
primary production
8. Consumers: obtained in diet and excess is
excreted
Nitrogen Cycle
Total nitrogen (TN)
Nitrogen gas
Nitrate (NO3) Nitrite (NO2)
Total nitrogen
All nitrogen in water sample except nitrogen gas
Nitrogen gas
Dissolve easily in water, but inert
Nitrate and Nitrite
forms oxides of nitrogen in water; nitrate is used by many plants, protists and microbes as a nitrogen source; nitrite is toxic
Forms of Nitrogen
Ammonia
Organic nitrogen compounds
Nitrate + nitrite + ammonium
dissolved inorganic nitrogen (DIN)
Nitrogen Reservoirs
1. Rocks: common in igneous rocks
2. Atmosphere: about 78% of the air
3. Oceans: Very soluble in water.
4. Freshwater: readily dissolves; unavailable to
plants or animals without bacteria fixation
5. Primary producers: Used by photosynthetic
plants, protists and bacteria
6. Consumers: Animals and fungi consume
autotrophs and use nitrogen to build proteins
Biological processes involving nitrogen in freshwater
Nitrogen fixation
Nitrification
Denitrification
Assimilation
Excretion
Nitrogen fixation
Nitrogen gas to ammonium
Nitrification
Ammonium to nitrate or nitrite
Denitrification
Nitrate to nitrogen gas
Assimilation
DIN or organic nitrogen incorporated into organic compounds
Excretion
Elimination by animals in ammonium, urea or uric acid
Nitrogen Fixation bacteria
Nitrogen gas to ammonia; symbiotic relationship with plants; bacteria gets sugar from plants and plants gets usable forms of nitrogen
Nitrogenous waste products
Silicon in water; found in water as silicate acid;
usually 13mg/L in water
Pollution
Any chemical, physical, or biological change in the environment that harms living organims
Eutrophication
Excessive nutrients that ultimately lead to oxygen-poor water; cannot sustain much life
Trophic level
Describes an organism's position in the food chain
How much energy is transferred from one trophic level to the next?
10%
Define Bioaccumulate/ biomagnify?
The concentration of toxins in an organism as a result of its ingesting other plants or animals in which the toxins are more widely disbursed
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