1. Show the vertical profiles of nutrient (NO3) and biomass (PON) during winter and spring
2. How can nitrogen be measured?
nitrite -> photometer
-> in acid solutions -> sulfanilamide forms diaconiumsalt with nitrite coupled on benzenering which is photoactive
nitrate -> photometer but indirect
. over nitrite calculated
Redfield ratio DIC = 2109, PO4 = 0.5, NO3 = 12. Mixing depth at 100m. Which is the limiting nutrient?
C:N:P -> P needs to be one (alles durch P teilen)
-> wenn ratio größer als redfield: phosphate is limiting
-> wenn ratio kleiner als redfield ist: phosphate is not limiting
- normally PON important as nitrogen is limiting planton growth in ocean
4. Biogeochemie: determine concentration of dissolved organic N and inorganic N
-> inorganic:
nitrite -> photometer -> in acid solutions -> sulfanilamide forms diaconiumsalt with nitrite coupled on benzenering which is photoactive
nitrate -> photometer but indirect, over nitrite calculated
-> dissolved organic nitrogen: gaschromatography
1. important factors stressing the role of microzooplankton role in food web (Microzoopl.)
a. animal nutrition (particulate organic substance)
1. what are otoliths? which function for fish/biologists (Ichthyoplankton)
a. sensory organ, in inner ear important for balance
1. differences foraminifera/radiolarian (form, propagation, etc.) (Zooplankton)
a. foraminifera: calciumcarbonate shells, single or multiple chamber systems, hosting endosymbionts, size 100 µm to a view mm, heterotrophic (not important in baltic)
b. radiolaria: silica skeleton, surrounded by cytoplasm, size: 20 µm to some mm, heterotropic (not important in baltic)
1. at least three characteristic taxon (genus, order) for Baltic sea, Antarctic, subtropical area? (+ species identification) . What is the abundance and size of species? (Zooplankton)
a. Antarctic (Polar): low diversity, view species high abundance, mainly calanoid copepod species
b. Tropics/subtropics: many species, low abundance: most species small, many cyclopoid copepod species
c. Baltic (shelf): view species, low diversity, many smaller species, view large taxa, Cladocera, meroplanktic larvae
d. Oceanic: more species, high diversity, very view meroplanktic larvae
Role of microzooplantkon in marine food web
Secondary producers
Intermediate
Improve to higher levels, food quality, trophic upgrade
Name four protostome species or genera (and the phyla they belong to) that can be found associated with mussel / oyster reefs of the Baltic and North Sea
- Mytilus edulis (Bivalvia) Lophotrochozoa
- Corbula gibba (Bivalvia)
- Musculus niger
- Abra abra
- Arctica islandica
- Also: ecdysozoa (häutungstiere)
- Hemigrapsus takanoi
- Hemigrapsus sanguineus (crustacea)
Name two deuterostome species or genera (and the phyla they belong to) that can be found associated with mussel / oyster reefs of the Baltic and North Sea
- Echinodermata
- Asterias rubens
- Ophiura albida
Name at least one red, green and brown algae species or genus that occurs in coastal waters of the Baltic and North Sea
- Red: porphyra (bangiophycee)
- Green: (Chlorophyceae) ulva compressa
- Brown: Fucus (fucophyceae)
Describe the life cycle of a typical red, green or brown alga
How are red, green and brown algae adapted to specific light climates in their habitats?
- Different chromophores have different absorption spectra
-
- Red: chl a d (deeper waters than green), phycobiline
- Green: chl a, b, carotene, xanthophyli
- Brown: chl a und c, fucoxanthin, xantophylli
What is a keystone species?
- Species with disproportionate influence on ecosystem (relative to mass)
- Eg. Asterias rubens, sea otter
8-What is a foundation species?
- Species that have strong role in structuring a community, can occupy any trophic level in foodweb
- Eg. Mytilus edulis
How can marine invertebrates cope with abrupt and more gradual reductions in seawater salinity?
o Change in sainity: body mass increase without good osmoregulation
- Osmoconformer:
o Have concentration of environment -> if changing they also have to change
o No active change in osmolarity in body -> need to adapt to environment:
o Short term: releasing ions
o Long term: aminoacids
o when more time: - keep ion conc the same but change org osmolyte conc
o = Metabolise aminoacids and keep potassium konzentration stable (inorganic ions only exchanged in extreme stress situation)
o Bsp: mytilus
- Osmoregulator: -> high acclimatization!!
o Ongoing process the whole time
o can take up or excrete ions. To keep osmolarity constant in body
o Inorganic ions (kalium) are released/taken up
o Fish artemia shrimp
10-What is an osmoconforming species? Give an example
- Mytilus edulis
- Regulator: paleomonetes, carcinus maenas
what class of particles are measured by the determination biogenic silicate? what problems can be expected using this method where terrestrial or riverine inputs are large? how can these problems overcome?
measurement of diatoms, silicoflagelates, radiolarian
lithogenic might be measured as well
overcoming the problem by using the koroleft method for determining only biogenic silicate
November: values of 10 µg/L chl were measured. Is this typical for this season?
what conditions lead to autumn bloom
thermocline destabilize and is deeper than in summer (cooling, fall winds)
higher mixing depth an replenishment of nurtrients in surface layers
still enough light for phytoplankton growth in this time of year
clear water phase (low zooplankton) after summer bloom
chl a normaly at 20 µg/l
How to measure: is the system dominated by autotrophic processes?
ratio of PP and respiration needed
phytoplankton biomass estimated with chla valze
- low-light adapted cells -> POC:Chl a 50:1
high-light adapted (unhealthy cells) 200:1
is a high amount of detritus present?
detritus: higher measured POC valvue than the calculated POC
in detritus the RR ratio is not valid, it has higher C-contents, because N and P are quicker remineralized
which nutrient is limiting
main differences in zooplankton communities between regions
polar: big copepods (euphasidea, cladocera), antarctic: salp (endemic species)
tropic: lucifer, soppharina
oceanic: no meroplankton (often siphonophores)
neritic: meroplankton (bsp. benthic larvae)
p
silicate is: Si:C = 6.8:1
when silicate conc high: diatoms will dominate as si is major nutrient
how does phytoplankton biomass develop if upper mixed layer is deeper than critical depth?
decreases, because R>P
if the structures of translocated communities change at differenr rates, which could be the reason
pros and cons of benthic sampling method
explaim two aspects of diversity and name most common parameters to measure diversity
diversity is the species richness and evennes within a defined area
parameters: simpon´s dominance index, shannon-wiener index, pilons evennes index
4 benthic foulig types
which set of parameters would you suggest to descrube community structure
biodiversity
distribution (regurlarly, patchy, random…)
dominance
species composition
% cover
biomass
functional groups
what is convergence of communities and how would you quantify the process
if the structures of translocated communities change at different rates, what could be the reason
which parameters define the coefficient of competition
which ecologically relevent parameters change with increasing depth
oxygen
nutrients
salinity
temperature
light
density increases with depth
give genus name and higher taxon name
what class of particles are mesured by the determination of particulate biohenic silicate?
shells of diatoms
silicoflaggellates
radiolaria
what problems can be expected using biosi method when terrestrial or riverine inputs are large
how can these problems be overcome
name most important nutrients for phytoplankton and in which seaon they are lowest in concentration
processes replenishing nutrientsin upper mixed layer for plankton growth
remineralisation
mixing
N2-fixation
river runoff and dust input
iddentify nutrients that limit phytoplankon growth
nitrate
phosphate
silicate
ion
which processes faciliate phytoplankton bloom in spring in temp ocean regions
better light conditions, longer day light
development of thermocline above critical depth
why is tropical ocean oligotrophic (except upwelling regions)
because of permanent thermocline that inhibits nutrient replenishment
convert number of phytoplankton cells counted in utermöhl chamber into actual abundance -> formel
N = Z (A/aV)
Z= cells counted
A= area of counting chamber
a=diameter * width of chamber/strip
V= volume in chamber
3 reasons why mortality coefficients derived from the sampling during the course might be unrealistic
net selection: too small fish and not quantitatively sampled
immigration of fish
efford was not exactly the same
1. Name 3 sampling filters. Pros and cons of each?
Quantitative: Van Veen grab and Peterson grab
à smaller impact
Qualitative: ‘Kieler Kinderwagen’
à trawl over distance, destroys benthos communities in that area but gives clear idea on the ecosystem
2. Which two aspects for species diversity are combined in Shanon-Weener-Index?
H = -Σpi * ln(pi)
where:
Σ: A Greek symbol that means “sum”
ln: Natural log
pi: The proportion of the entire community made up of species i
à combines species richness and species evenness (distribution of individuals among species)
3. Which factors are used to sort benthic organisms?
Size à sort higher taxa à species ID
4. Which parameter limits the diversity between Flansburg and Lübecker Bucht?
· Salinity
· Nutrient availability
· Fishing pressure
9. Bray-curtis index? purpose + which parameters used?
Most popular quantitative resemblance coefficient
1. Anatomical characters (carp vs cod) (Digestion morphology/ range of functions of swimbladder and sensory perception)
Carp: Physostomes, two chamber swim bladder, extensions from the swim bladder to the inner ear called ‘Weber appendages’
Cod: Physoclists
1. Do fishes drink water? If so which?
The tissues of marine fishes are less salty than the surrounding water
à Water is continually leaving the body of a marine fish through its skin and gills
à To keep from becoming dehydrated, a marine fish drinks large amounts of water and produces a small amount of concentrated urine. In addition, its gills are adapted to secrete salt
The tissues of a freshwater fish are saltier than its surrounding environment
à Water is continually entering the body of a freshwater fish through its skin and gills
à Freshwater fishes do not drink water, and they produce large amounts of dilute urine
Compare anatomy of Carp and Herring in a) digestion, b) maintaining buoyancy and c) sensory organs and most prominent brain structures
a) Herring:
Carp:
b) Herring: Physostoma
Carp: Physostoma, two chamber swim bladder
c) Herring: Weber appendages (hearing and communication), no lateral line
Carp: Weber appendages (hearing and communication), lateral line?
1. Explain evolution (analogy) of cartilage and bony fish for maintaining buoyancy
Bony fish mostly have a gas-filled bladder called the swim bladder. This was originally developed as a respiratory organ and is now used for maintaining buoyancy. Cartilage fish have no swim bladder. Here, buoyancy is reached through squalene (fat) in their liver.
1. Copepoda and species for each.
· Copepoda:
o Calanoida: first antennae longer that >half of the body, movable joint behind the sixth thoracic segment
o Cyclopoida: movable joint between the fifth and sixth thoracic segment
o Harpacticoida: lack of obvious divisions between the cephalothorax and the abdomen
Resource for three dimensional growth of periphyton communities plus analogous growth architecture?
Growth architecture is of periphyton very diverse. Resource for growth are light, and nutrients, P, N, C. For Diatoms also Silicate. Growth architecture can be gliding prostrate, or adhesive prostrate, solitary upright type, belt shaped, stalked solitary or colonial, tube dwelling or filamentous colonial type.
1. Aim of Ichthyoplankton studies. How sampled?
Sampling: Nets with 50 µm and larvae 300 µm
Vertical hauls from non-moving ship, towed sampling gear, neuston sledge, bongo, mocness, longhurst hardy
a. Name 3 pros and cons of barcoding and explain them briefly
Pros:
Sometimes full specimen don’t exist -> can be find with eDNA
Identify putative new species
Increase rate of species ID
Cons:
(Need to have high dna sample -> need to be pure for barcoding)
Taxonomic bias: plants don’t have universal barcode
Always needs to be referenced to database (not only barcoding used)
Matches wont be exact bc of mutation
Expensive compared to usual taxonomy
preservation techniques for dna synthesis
freezing -20
shock/ dry freezing -70
ethanol
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