Why does reducing fertilizer use and increasing efficiency in agriculture not affect food security?

Chemical fertilizers have made an indelible contribution to China's consecutive years of agricultural harvests, but as chemical fertilizer use in China has increased, its efficiency in boosting crop yields has been declining, and it has even brought impacts on the ecological environment. In fact, reducing fertilizer use, especially for cash crops such as vegetables and fruits, will not affect national food security, and through soil testing and formulated fertilization technology and the use of organic fertilizers, efficiency can also be improved, which is more conducive to sustainable agricultural development. This requires promoting the optimization and upgrading of the fertilizer structure and extending new types of fertilizers and scientific fertilization methods.

Recently, relevant departments launched an action to achieve zero growth in chemical fertilizer use for three types of crops, and the topic of chemical fertilizers subsequently sparked heated discussion online. Some netizens feel that the reason some melons and vegetables no longer taste like melons and vegetables is that farmers use large amounts of chemical fertilizers, and that chemical fertilizers cannot be relied upon, while organic agricultural products are what is healthy. Others believe that today's high land output depends entirely on chemical fertilizers, and they worry that reducing chemical fertilizer use will affect food security. The author believes that we must correctly understand the role of chemical fertilizers in agriculture, and that reducing chemical fertilizer use while increasing use efficiency will be beneficial to food security.

“If a crop is to bloom, it all depends on fertilizer.” Traditional farming culture mainly used farmyard manure to increase soil nutrients. It was only from the 1970s that Chinese farmers began to widely use chemical fertilizers. For a time, governments at all levels were even worried that farmers could not buy chemical fertilizers. Over the past 35 years, China's chemical fertilizer use increased at an average annual rate of 5.2%, and agricultural output generally showed a growth trend. It can be said that, as an achievement of agricultural scientific and technological progress, chemical fertilizers have made an indelible contribution to China's consecutive years of agricultural harvests.

However, although chemical fertilizer use has been increasing, its efficiency in boosting crop yields has been declining. Because the fertilizer utilization rate in the current season is only 33%, China's average fertilizer application per mu is higher than that of developed countries, at 2.6 times that of the United States and 1.7 times that of South Korea. Excessive chemical fertilizer use not only increases agricultural costs but also brings impacts on the ecological environment. In reality, while the application of chemical fertilizers increases yields, there may indeed be cases in which the quality of agricultural products declines, such as watermelons not being sweet or cucumbers not being fragrant. At such times people often attribute this to chemical fertilizers. In fact, the decline in quality is not because chemical fertilizers are applied, but because the amount, proportions, and methods of fertilizer application are inappropriate.

The reasons for excessive chemical fertilizer use are very complex, including both reasons related to operating methods and problems with basic conditions, and they are closely related to the reality of China's agriculture as a whole transitioning from traditional to modern. Take vegetables as an example: most have a short growth period and high yields. For example, cucumbers can reach a yield of more than 5,000 kg per mu, so their fertilizer demand is high. Because fertilization methods are relatively backward, vegetable greenhouses or open-field cultivation mostly use broadcasting chemical fertilizers or flushing them on with water. At the same time, because the economic benefits of vegetables are relatively high and fertilizer costs account for a small proportion, farmers' awareness of scientific fertilization is not strong. At present, vegetables have not yet achieved higher prices for better quality, which leads some vegetable growers to one-sidedly pursue yield and apply more fertilizer while neglecting qualities such as flavor and taste.

So, will reducing chemical fertilizer use affect national food security? Not only will it not, but reducing use can also achieve efficiency gains and is more conducive to sustainable agricultural development.

First, the crops with relatively large chemical fertilizer use in China are mainly concentrated in vegetables and fruits, especially protected vegetables. China uses 8% of the world's arable land to produce 52% of the world's vegetables and 22% of the world's fruits, and the chemical fertilizer use for fruits and vegetables is also substantially higher than abroad. Therefore, reducing the chemical fertilizer use for these cash crops will not affect national food security.

Second, in recent years, soil testing and formulated fertilization technology for grain crops has become relatively mature. Through soil testing and formulated fertilization and the use of organic fertilizers, chemical fertilizer use can be reduced, and cost savings and efficiency gains can also be achieved. In recent years, because the central government has vigorously promoted soil testing and formulated fertilization, demonstration areas have reduced unreasonable chemical fertilizer use per mu (in pure nutrient terms) by 1 to 2 kg, and the national growth rate of chemical fertilizer use has declined.

Third, according to international experience, chemical fertilizer use first shows rapid growth, and after reaching a peak it maintains a trend of steady decline with some fluctuation or continuous decline. Chemical fertilizer use in the European Union and some developed countries in North America began to decline in the 1980s, and countries such as Germany and France even reduced it by 30% to 50%. Of course, this process is not automatic; it must be achieved through technological progress and changes in production methods.

In the future, while improving the utilization efficiency of traditional chemical fertilizers, it is necessary to promote the optimization and upgrading of the fertilizer structure and extend new types of fertilizers and scientific fertilization methods. Some people think that new types of fertilizers are too expensive. In fact, new types of fertilizers have the characteristics of low application rates and good effects. Although the input cost is somewhat higher, the input-output ratio is also higher. Take the purchase of biological organic fertilizer products, which are used in relatively large amounts, as an example: calculated at 200 kg per mu, the cost is no more than 300 yuan. Overall, farmers can afford to use them. Of course, if there is financial subsidy support, farmers will be even more willing to accept them.