Episode 20 Nitrogen Fertiliser. We look at the cycles operating within the ‘rule of return’, focusing on the nitrogen cycle, nitrogen availability being a common limiting factor in plant growth. Various traditional methods of controlling the nitrogen content of the soil are discussed, before Justus von Liebig’s work sparked a desire to solve the problem of nitrogen fixation artificially, through industrial scientific processes. Eventually Fritz Haber discovered a viable method, and human civilization has become reliant on the reactive nitrogen it produces. We look at the application of fertiliser, its controversies and downsides, and discuss the extent of organic farming in Britain. Finally, we look at the contribution of James Rebanks, a British farmer, to the debate.

0:00 Recap
1:22 The nitrogen cycle
3:04 The problem of fertiliser
7:14 Fertiliser application
9:21 Controversy
13:09 Some disasters
14:25 Environmental problems
19:13 James Rebanks

Sources:

https://vaclavsmil.com/wpcontent/upl...
https://pubs.rsc.org/en/content/artic...
https://foodfoundation.org.uk/news/fo...
https://www.gov.uk/government/statist...
https://www.bbc.co.uk/programmes/arti...
https://www.nfuonline.com/updatesand...
https://www.yara.co.uk/cropnutrition...
https://www.ft.lk/frontpage/Inorgani...
‘English Pastoral: an Inheritance’, James Rebanks.

Media used:
Traipsing through the country by Greg Fellman, from Pixabay under a Creative Commons License,
Make Fruitful the Land, British Council, under a Creative Commons License