China cut fertilizer use and still increased crop yields (2018)

From the article:

Specific, evidence-based recommendations were made to 21 million Chinese farmers over a decade, offering them detailed advice about which variety of crop to use, exactly the best time to plant, how many seeds to sow and how much fertilizer to use.

The detailed guidance led to an increase in the amount of maize, wheat and rice produced, with crop yields increasing at an average of 11%.

Meanwhile, fertilizer use was reduced by an average of 15% per crop, saving 1.2 million tonnes of nitrogen, according to the study published in Nature.

And the combination of greater yields and less fertilizer led to total economic savings of $12.2bn for the farmers.

…

The scale of the project was vast and required a significant investment of both manpower and money which would be hard for other developing countries to replicate.

The farmers were convinced to change their practices as a result of 14,000 workshops, on-site demonstrations and outreach programmes. This was achieved with the help of more than 1,000 researchers, 65,000 bureaucrats and technicians as well as 140,000 representatives from agriculture businesses.

…

The success in China is also partially due to its history of over-use of fertilizers, as it has strived to produce enough food to keep pace with population growth.

Chinese farmers use an average of 305 kilograms of nitrogen per hectare per year – more than four times the global average. China has been a significant contributor to the world’s increased use of fertilizers, and Asia’s fertilizer consumption has grown faster than any other part of the world.

Since then, the trend has continued. China fertilizer consumption peaked a decade ago.