fertiliser

organic fertiliser is better for the environment

chemical fertiliser can harm the soil

farmers use fertiliser to improve crop yields

compost can be used as a natural fertiliser

balanced fertiliser contains all necessary nutrients

excessive fertiliser can lead to water pollution

fertiliser application should be done carefully

nitrogen fertiliser is commonly used in agriculture

phosphorus and potassium are essential fertiliser nutrients

the right fertiliser can help plants grow healthy

Nitrogen fertilisers have altered the balance of chemical isotopes in peat bogs.

Cutting forests releases greenhouse gases from the wood and the soil, and fertilisers create greenhouse gases too.

Meanwhile higher fertiliser and energy costs will crimp farmers' margins everywhere.

But initial evidence from the German dairy and fertiliser industries suggests that even heavy users respond to higher prices.

Fertiliser shortages are even harder to cover: new potash mines take 5-10 years to build.

So it means Africans are just using less fertiliser.

Farmers have switched from gas to oil heating; ammonia, fertiliser's gas-intensive ingredient, is now imported instead of being made locally.

VOICE OVER: The whales' fecal fertiliser allows for the growth of phytoplankton.

But fertiliser costs remain high, meaning more reassurance will probably be needed in the future.

In recent years, human sewage and fertilisers from intensive farming have increased plankton blooms in the Gulf, providing extra jellyfish food.