Plankton Preservation Flashcards

1
Q

How soon should fixation and preservation of samples be carried out

A

Within 5 mins of collection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is lugols iodine

A

10g iodine, 20g potassium iodide in 200ml distilled water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Advantages to Lugols iodine

A

Adds weight to cells and helps phytoplankton sells sink to bottom of settling chamber.
Not very toxic
Good preservative for soft and hard tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the disadvantages of Lugols iodine

A

Breaks down in sunlight. Need to store samples in dark
Can change colouration and impair ID
(Phytoplankton from green to brown)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How are plankton samples stored

A

Preserved samples stored best in well ventilated room at <25°C
Accurate detailed labeling crucial pencil rather than pen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Two enumeration sample analysis methods

A

Volumetric
Gravimetric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the volumetric method work

A

Plankton sample filtered through suitable mesh size.
Interstitial water removed with blotting paper.
Filtered plankton transferred to measuring cylinder in 4% buffered formalin
Displacement volume obtained by recording the vol of fixative in measuring jar displaced by the plankton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does the gravimetric method work

A

Plankton filtered and blotted dry
Plankton wet weight taken on pre weighed filter paper or tin foil
Sample can be dried in oven at 60°C prior to weighing to obtain dry weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does Utermöhl method work

A

Plankton sample left to settle on bottom of cylinder
Bottom cylinder viewed on inverted microscope
Counts made on microscope
Often used to enumerate phytoplankton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the problem with Utermöhl chamber method

A

Certain forms voutant - do not settle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Example of sub sampling method used for plankton

A

Folsom plankton splitter
Ensures plankton are evenly dispersed through subsamples

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Give example of technological advances in plankton analysis

A

Underwater cameras capable of recording plankton of organisms at resolution that allows for identification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly