Mega-cities to cause severe agricultural losses
It is no secret that our global population is increasing in an exponential fashion, and this is placing an ever-greater strain on the worldwide food chain. In the simplest analysis, more people than ever before need more food than ever before. Looking a bit more deeply, the issue is regional. Developing nations where food is scarcer are seeing their populations increase a greater rate than areas where food is more plentiful. This is clearly a problem and the food chain in many places is becoming increasingly precarious as a result.
The loss of land suitable for growing crops is a huge problem across the world. Each year approximately three million hectares of cropland become unusable due to soil erosion and degradation. A further four million hectares are lost each year to urban conversion, making space for highways, housing factories and everything else needed for a modern city.
A new report from Proceedings of the National Academy of Sciences of the United States of America (PNAS) argues that this loss of land suitable for farming is set to get much worse over the next decade.
Roughly 60% of the world’s cropland is located on the periphery of cities, leading to the PNAS prediction that the growth of a relatively small number of mega-cities could lead to the loss of almost 3% of all land suitable for growing crops across the world by 2030.
3% does not sound like a lot in isolation, but this is where the regional pressures on the global food chain come back into consideration.
The majority of new mega-cities are destined to be heavily concentrated in Africa and Asia – the ‘developing world’. The stand out examples of this are New Delhi in India and the Pearl River Delta in China which are projected to be home to 37 million and 60 million people respectively by 2030. Countries such as India and China are home to cropland which is more than 1.7 times as productive as the global average and they will be losing a disproportionate amount of it. That is without even mentioning Africa which has serious and well-known issues with its food chain already.
The loss of this cropland is likely to go hand in hand with other sustainability and environmental issues. Solving this issue will require intelligent local governance and it is likely that we will also need to rethink the global food chain somewhat. Famine is often thought to be a natural phenomenon, but this is not actually true. Famines generally occur as a result of bad political choices and agricultural mismanagement, and it is not hard to imagine a scenario where a rush for urban development in developing nations leads to a neglect of the local food chain and all the terrible consequences which come with that.