The World Business Council for Sustainable Development and IUCN have recently released this valuable overview of global agricultural practices and the potential of sustainable practices.
From one section:
As wealth increases so does per capita calorie intake. The demand for a more diverse diet that includes animal protein such as meat and milk products requires more land to produce. What role do consumers play when choosing their diet? Do consumers need to be encouraged to have a vegetarian diet?
Meat consumption in China has more than doubled in the last 20 years and it is projected to double again by 2030.
Consumer concerns about food safety, the origin of produce and environmental impacts are also driving improvements in food quality throughout the global agri-food value chain.
Diet changes in richer countries towards increasing consumption of fruit and vegetables contribute to generating less calories per hectare. For instance China is gradually abandoning field crops – such as cereals – to produce vegetables and fruit; it has now become the world’s largest producer of vegetables and apples.
Producing meat, milk, sugar, oils and vegetables typically requires more water than producing cereals. Average water use also differs greatly between feed-based meat production and grazing systems.
Food production to satisfy a person’s daily dietary needs takes about 3,000 liters of water – a little more than one liter per calorie.