Agricultural weight loss does not affect food security

Chemical fertilizer plays an important role in the continuous bumper harvest of agriculture in China, but with the increase of the amount of chemical fertilizer in our country, the efficiency of increasing crop yield is decreasing, and even has an impact on the ecological environment. In fact, the reduction of chemical fertilizer, especially the reduction of chemical fertilizer for cash crops such as vegetables and fruits, will not affect the national food security, and efficiency can be achieved through soil testing and formula fertilization technology and the use of organic fertilizer. more conducive to the sustainable development of agriculture. It is necessary to promote the optimization and upgrading of fertilizer structure and popularize new fertilizers and scientific fertilization methods.

A few days ago, the relevant departments launched a zero growth campaign for the use of chemical fertilizers for three types of crops, and the topic of chemical fertilizers has sparked a heated discussion on the Internet. Some netizens think that nowadays some melons and vegetables have no taste of melons and vegetables because farmers use a lot of chemical fertilizers, which are unreliable and organic agricultural products are healthy. Others believe that today's high land output depends on chemical fertilizers, and they are worried that the reduction of chemical fertilizers will affect food security. The author believes that in order to correctly understand the effect of chemical fertilizer on agriculture, increasing the use efficiency while reducing the amount of chemical fertilizer will be beneficial to food security.

"A flower in a crop depends entirely on fertilizer." Traditional farming culture mainly uses farm manure to increase soil nutrients. It was only in the 1970s that Chinese farmers began to widely use chemical fertilizer. For a time, governments at all levels worried that farmers could not buy chemical fertilizer. Over the past 35 years, China's chemical fertilizer use has increased by an average of 5.2% a year, and agricultural output has shown an overall growth trend. It can be said that, as a result of the progress of agricultural science and technology, chemical fertilizer has contributed greatly to the continuous bumper harvest of agriculture in our country.

However, although the use of chemical fertilizer is increasing, its efficiency in increasing crop production is declining. As the utilization rate of chemical fertilizer in the current season is only 33%, the average amount of fertilizer used per mu in China is higher than that in developed countries, 2.6 times that of the United States and 1.7 times that of South Korea. Excessive use of chemical fertilizer not only increases the cost of agriculture, but also affects the ecological environment. In reality, the application of chemical fertilizer to increase the yield at the same time, there may be a decline in the quality of agricultural products, such as watermelon is not sweet, cucumber is not fragrant and so on. At this time, people often attribute it to chemical fertilizer. In fact, the decline in quality is not due to the application of chemical fertilizers, but to the improper quantity, proportion and methods of fertilizer application.

The reasons for the excessive use of chemical fertilizer are very complicated, including both the mode of operation and the basic conditions, which are closely related to the reality of the overall transformation of China's agriculture from traditional to modern. Take vegetables as an example, most of them have short growth period and high yield, such as cucumber with a yield of more than 5000 kg per mu and high fertilizer intensity. As the way of fertilization is relatively backward, vegetable greenhouse or open field cultivation often use chemical fertilizer or flushing with water. At the same time, because the economic benefit of vegetables is relatively high and the proportion of fertilizer cost is not high, farmers' awareness of scientific fertilization is not strong. At present, vegetables have not yet achieved high quality and high price, resulting in some vegetable farmers one-sided pursuit of yield and more fertilization, but ignore the flavor, taste and other quality.

So, will the reduction of chemical fertilizer have an impact on national food security? Not only will not, but also reduce the amount can also achieve efficiency, more conducive to the sustainable development of agriculture.

First, the large amount of chemical fertilizer used in China is mainly concentrated in vegetables and fruits, especially in facility vegetables. China produces 52% of vegetables and 22% of fruits with 8% of the world's arable land, and the amount of chemical fertilizer for fruits and vegetables is also much higher than that of foreign countries. Therefore, reducing the amount of chemical fertilizer used for these cash crops will not have an impact on national food security.

Second, in recent years, grain soil testing formula fertilization technology has been more mature, through soil testing formula and the use of organic fertilizer, can reduce the amount of chemical fertilizer, but also achieve cost-saving and efficiency. In recent years, due to the vigorous promotion of soil testing and formula fertilization by the central government, the unreasonable amount of chemical fertilizer per mu in the demonstration area has been reduced by 1 to 2 kg, and the growth rate of chemical fertilizer use in the whole country has declined.

Third, according to international experience, the amount of chemical fertilizer increases rapidly at first, and then keeps falling steadily or continues to decline after reaching the peak. The amount of chemical fertilizer used in some developed countries in the European Union and North America began to decline in the 1980s, and even decreased by 30 to 50 percent in countries such as Germany and France. Of course, this process is not natural, but should be realized through technological progress and changes in the mode of production.

In the future, while improving the utilization efficiency of traditional chemical fertilizers, it is necessary to promote the optimization and upgrading of fertilizer structure and promote new fertilizers and scientific fertilization methods. Some people think that the new fertilizer is too expensive, in fact, the new fertilizer has the characteristics of low consumption and good effect, although the input cost is higher, but the input-output ratio is also high. Take the relatively large amount of bio-organic fertilizer products purchased as an example, the amount of bio-organic fertilizer per mu is calculated according to 200 kg, and the cost is no more than 300 yuan. On the whole, farmers can afford to use it. Of course, farmers will be more willing to accept it if it is supported by financial subsidies.