Recipient control and legislation

Question 1

What is the purpose of “16 Swedish Environmental objectives” and which of them are relevant for Recipient Control?

Answer 1

The 16 Swedish objectives are based on the global Sustainable Development Goals and is what we need to achieve to make sure we have a good environment. For recipient control, “natural acidification only”, “a non-toxic environment”, “zero eutrophication”, “flourishing lakes and streams”, “good quality groundwater” are of importance.

Question 2

How can you with an easy and cheap method show if a water body is stratified?

Answer 2

Measure the temperature at different depths. In a stratified lake there are big temperature differences.

Question 3

What is the compensation depth and how do you measure it?

Answer 3

The compensation depth is where the rates of photosynthesis and respiration are equal. It’s 2 x visibility depth.

Question 4

How does Oxygen-free bottoms occur?

Answer 4

Stratification of water –> nutrient rich water in the top–> algae blooming –> Dead algae sink to bottom –>Degradation of algae requires oxygen–> oxygen free bottom

Question 5

Which parameters affect the speciation of iron (Fe) in the water column?

Answer 5

pH, redox, organic material

Question 6

How does the speciation of iron (Fe) affect nutrient (P,N) in the water column and in the sediments?

Answer 6

Nutrients is bound to iron-hydroxides in oxygen rich environments and when they come to anoxic environments iron(III)hydroxides turn into iron(II) which causes the nutrients to become free in the water/sediments as well.

Question 7

How does the speciation of iron (Fe) affect metals (e.g. Cu) in the water column and in the sediments?

Answer 7

Metals are bound to iron-hydroxides in oxygen rich environments and when they come to anoxic environments iron(III)hydroxides turn into iron(II) which causes the metals to become free in the water/sediments as well.

Question 8

Which parameters would you measure to identify eutrophication of a lake and where would you measure them?

Answer 8

Oxygen level at bottom, visibility depth, how much nutrients close to surface, TOC level close to surface, temperature through water column (pH in water column)

Question 9

When during the year would you try to identify eutrophication and why then?

Answer 9

Summer because that is why algae’s bloom and make the problem with for example anoxic bottoms worse.