By 2050, it is estimated that rising populations and changing diets may lead to a 70 percent increase in global food demand.

One ingredient, which will play an important role in making sure we have enough food to feed ourselves, is phosphorus. This mineral is vital to plant growth and is a key component of fertiliser.

Yet, according to some experts, minable reserves of phosphorus may be completely depleted in a few hundred years.

We also continue to use excessive amounts of phosphorus in agriculture, which creates problems such algal blooms and nutrient pollution when the fertiliser runs off into our waterways.

One sewage plant in London, however, is dealing with both the shortage of phosphorus and also the environmental damage its inappropriate use causes. Using technology developed in Canada, the plant is turning faeces into fertiliser and creating a new, greener way to grow crops.

Join Amandeep Bhangu in London, UK as she visits Europe's first facility that is turning raw sewage into fertiliser. 

earthrise can be seen each week at the following times GMT: Monday: 2230; Tuesday: 0930; Wednesday: 0330; Thursday: 1630.

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Source: Al Jazeera