M2-1 Flashcards
Water quality
The chemical, physical, and biological characteristics of water . Lvl of quality is often based on the use of water
5 physical indicators
1) total dissolved solids
2) conductivity
3) total suspended solids
4) turbidity
5) water colour
7 chemical indicators
1) pH
2) boi oxygen demand (BOD$)
3) DO
4) hardness
5) TN
6) TP
7) heavy metals and pesticides (toxic materials)
5 biol indicators or water quality
1) bacteria content
2) EPT count (classes that are sensitive)
3) community comp
4) diversity index
5) dominance of pollution tolerant organisms
What control primary production
Nutrients
What is a key way to understand biological processes?
Understand nutrient cycles
dissolved vs particulate matter
often an arbitrary distinction. Dissolved matter can pass through a filter, while particulate cannot.
often the cutoff for dissolved is between 0.5 to 1 microm
total dissolved solids
determined using mass that is dissolved in water (2microm trheshold)
what is the range of TDS in tap water
170-410
conductivity
the electricity is transferred through water via ions.
note specific conductance is correct to 25 degrees
TSS
the mass of particles retained on a filter
turbidity
determined via the amount of light scatter or absorbed. more parties haas more scattering (cloudy)
what is the range of conductivity for tap water
50-800 mS/cm
pH meaning
potential of hydrogen- a measurement of acidity
what does pH dictate
- biological activity in a water system
- most biol sys like pH=7
what is the risk of a low pH system?
the mobilization of toxic metals
Alkalinity
the buffering capacity of water (neutralize acids)
- measure in mg/l of equivalent carbonates
often varies with geology and rock sources
hardness
the sum of mg and ca ions in the water. this acts and an indicator for the ability for water to precipitate soap.
an important factor in the domestic water supply.
biogeochemistry
chemistry in an environmental context w/ emphasis on the living and non living components of an ecosys
nutrients
elements that are essential for plant growth
where is phos are incorporated into
used in: lipids, nucleotides and nuc acids
sources of nutrients
through precip, weathering/errosion, water, mirco orgs (inot bio avaiable formes), decomp of larger orgs
macro nutrients
N, P, O, C, (and K)
micronutrients
Fe, Cl, Cu, Mn, Zn, Mo Bo
nutrient use by primary vs heterotophs
primary can use nut in an inorg form (like nitrite and phosphate) while hetero much aquire in the org form
where is nitrogen incorporated into
AA and proteins, along with nucleotides and nuc Acid
stoich
the balance of energy and elements- how they impact living systems
redfeild ratio
106 C: 16 N: 1 P (phos is often limiting if these ratios hold)
this ratio promotes the balanced growth of organisms
nutrient assimiliation
the acquisition of nutrients by orgs. often incorperated into biomass
remineralization
the breakdown or OM into biologically available forms.
a form a recycling often completes nutrient cycles
leibig;s law of minimum
the element or resource with the least relative amount will limit growth and production.
the idea that a single nut will limit the primary prod of a system
common limiting nutrients
N and P
