Fertilisers and nitrogen, pesticides and pollution
This page is a brief summary of these significant issues and their relevance to churches and church members.
The nitrogen cycle
Compared to global warming and carbon emissions, there is much less awareness of this area of concern.
It has been cited as one of a catalogue of ‘planetary boundaries’ which we dare not transgress – but are in danger of doing so.
Nitrogen is vital for plant metabolism. Although atmospheric nitrogen is abundant (about 78% of the atmosphere), it mostly can’t be used by plants, but has first to be ‘fixed’ (processed into useable compounds) mainly by bacteria.
Human activities have drastically affected the nitrogen cycle. The use of chemical fertilisers has more than doubled natural fixation!
This makes it easier for crops to grow, but is not necessarily the good thing it might seem:
- The natural uptake of nitrogen compounds by plants is thrown out of balance, disturbing eco-systems, threatening biodiversity, and causing eutrophication – the phenomenon when over-nourished algae suddenly cover an expanse of water;
- This starves the water of oxygen and kills off other organisms. The oceans themselves are now becoming depleted in the oxygen needed to support life;
- Nitrogen compounds especially oxides from vehicles and aeroplanes are toxic and add to the problems of global warming, ozone depletion and acid rain. Vehicle use is substantially responsible for central London’s unacceptable air quality.
So, we should curb our use of fertilisers and our nitrogen emissions from flying and driving.
Rachel Carson wrote a book called ‘Silent Spring’ in 1962. It’s about the promiscuous use of toxic pesticides in post-WW2 USA. It is still widely read. As well as being deeply moving, it is excellent science (though manufacturing lobby groups have tried to cast doubt on it).
Silent Spring is credited with launching the whole environmental movement. It led to the foundation of the US Environmental Protection Agency (EPA) (since 2018 tragically under threat). Rachel Carson was also the inspiration for Al Gore’s campaigns concerning the environment and climate change.
‘Silent Spring’ did lead to a cut in pesticide use, although this still continues including in our own back gardens.
Organically grown food should be free of pesticides. See Food and Drink.
To read more