Fertilizers and Pesticides

Fertilizers and Pesticides - Transcript

Aims of the session
Learn about fertilisers and their effects on the environment Be able to answer exam questions on the effects Learn about Pesticides and their effects Summarise the key points about pesticides

Fertilisers and Pesticides

Fertilisers

The process of Eutrophication

The process of Eutrophication cont

Biochemical Oxygen Demand BOD
This measures the rate of oxygen consumption by a sample of water and therefore gives a good indication of eutrophication A high BOD means lots of organic material and aerobic microbes i e eutrophication

The nitrate concentration falls during spring and summer and rises during autumn and winter Less algal growth as autumn begins Possibly all plants have died

Pesticides

Pesticides
Include
Herbicides
Insecticides Fungicides Bactericides

Pesticides

Persistence Bioacculmulation Lipid solubility

Bioaccumulation
E g DDT
w a te r z o o p la n k to n 0 0 4 p p m s m a ll fis h 0 5 p p m la r g e f is h 2 ppm b ir d s 25 ppm