No matter how much fertilizer, the land is still hungry.

Since this issue, Ecological Weekly has launched a column entitled "Ecological Restoration, Beautiful Golden Autumn", focusing on ecological restoration of soil, mines, wetlands, forests, rivers, etc., covering and reporting typical cases in various fields. We look forward to your attention.

On September 13, 30 agricultural experts from 8 provinces gathered in Xihua County, Zhoukou City, Henan Province, including the stationmaster of soil and fertilizer stations in 8 provinces. In the hinterland of this grain area, they will observe a chemical fertilizer reduction experiment that has lasted for many years, measure production on the spot, and complete the evaluation of the results. Li Rong, director of the cultivated Land quality Inspection Department of the National Agricultural Technology extension Center of the Ministry of Agriculture, pulled out two soybean plants grown in experimental plots and general plots. One root stick straight down and can count more than 50 effective rhizobium. One root grows horizontally, and there are more than 20 rhizobium, which are still rotten.

Rhizobium can help soybeans fix nitrogen from the air and promote growth. Therefore, the survival rate of rhizobium is an index to measure the growth and health of legumes.

Li Rong simply asked to dig up the land and have a look. The improved land appears soft, known as "sponge soil", while the long-term use of chemical fertilizer soil porcelain, the masses say this is called "multi-layer steamed bread". Only then did everyone understand: "the roots can't take root, so it's no wonder they grow horizontally." The application of "carbon adsorbed polyglutamic acid organic water soluble fertilizer" in the experimental plot has achieved remarkable results in chemical fertilizer reduction and soil improvement, and has been tested by more than 10 million mu in 64 regions of 12 provinces.

The soil is hardened and the root system of the plant cannot be opened until it is deeply rooted.

At the end of September, Xihua in Zhoukou was in the autumn harvest of corn and soybeans, but Cao Zitang, a big grain grower, was in no hurry. On September 13, the National Agricultural Technology extension Center of the Ministry of Agriculture organized to observe his improved land. He is a major grain grower in the country, and he is equipped with "high-end" equipment such as spraying drones and self-propelled sprayers. In other people's fields, the machines are busy harvesting, and Cao Zitang has to wait another week.

Different from the surrounding plot, the restored plot of Cao Zitang did not dry up, but maintained the mature state of green living stalk. "the land is nutritious and has strong vitality. If it is not harvested, it is still filling, and it can still increase production." Cao Zitang said, "crops were particularly prone to drought a few years ago and had to be watered repeatedly. Only later did I know that the soil had hardened and that the roots of the plants were not deep enough to open. "

Pull out Cao Zitang's corn control, the root is obviously strong, spread out a lot, firmly grasp the soil. The consolidation of the land is not easy to see with the naked eye, but it is obvious to the plants. Last year, Xihua County asked him to experiment with spraying a water-soluble organic fertilizer called "carbon adsorbed polyglutamic acid" while greatly reducing chemical fertilizers, which he did not want to take the risk. In the end, the deputy county magistrate in charge of agriculture promised to compensate for the losses, but he only tried a few plots. This year, he put all the polyglutamic acid he could get into the field without saying a word, and he didn't even want to stay in the field.

With close planting, improved varieties and other methods, others beat 400jin of soybeans per mu, he beat 700jin of improved land, and others beat 700jin of corn per mu, he beat 1400 jin. Corn used to use more than 100 jin of chemical fertilizer per mu, but it has dropped to 60 jin this year. Big growers in Shanxi and Hubei all come to learn from the classics.

"during the pollination period this year, there was heat damage, the weather was extreme, and the yield contrast after land restoration was even stronger. In a normal year, the harvest of my field is 30% higher than that of consolidated land. I am sure to hit more than 200 jin, and the quality is better. " Cao Zitang said.

In Laiwa Village, Xihuaying Town, many plots have been repaired for five years. This year, Cui Jinli's soybeans attracted villagers from Shiliba Township. Such good beans have never been grown in the sand. The harvest began on September 22 and the yield per mu exceeded 400 jin. But Cui Jinli is no longer surprised. Four years ago, the restored land planted wheat for the first time, and experts from the Provincial Academy of Agricultural Sciences estimated that the yield per mu was 1200 jin. He did not believe it. Because the wheat here has never talked about jin, only about bags: generally, four or five bags per mu, about 500 jin. The result impressed him deeply, with a total of 10 mu and 4 points of land and hit 12880 jin.

As he spoke, a bean bug climbed onto Lao Cui. If chemical fertilizers and pesticides are used too much, worms are not common in the fields. After the land was restored, the worms came back. Lao Cui said that in those years, the wheat was green and yellow, and if he couldn't find the reason, he sprinkled more chemical fertilizer. Only later did I know that the herbicide followed Rain Water to the depression, so he "burned" the wheat. Farmers do not know, and will not "detoxify" the soil, only thinking that there is not enough fertilizer, and finally there is a vicious circle.

Today, the organic water-soluble fertilizer that farmers use to repair the soil is called "Nai'an", and its inventor is an authentic farmer: Dang Yongfu. He is 50 years old this year, and has spent 26 years of painstaking efforts on protecting the land. He has won the National May 1 Labor Medal, the United Nations International Academy of Ecological Life Sciences, and the "Science Star" medal of the International Ecological Security Cooperation Organization.

In Dang Yongfu's view, the long-term use of chemical fertilizer on land is like people blindly eating big fish and meat, naturally getting sick after a long time, high blood lipids and high blood pressure, and all the complications have come. No matter how much chemical fertilizer, the land is still hungry, need a balanced diet, organic matter, minerals are indispensable.

Polyglutamic acid is non-toxic, hydrophilic and biodegradable. it has been recognized as a soil regulator to balance acid-base, solidify heavy metals, increase fertilizer efficiency and increase plant yield. Dang Yongfu's scientific research results have significantly reduced the production cost of polyglutamic acid, and showed good results in a large number of long-term field verification.

Overcome difficulties and overcome the side effects of herbicides and chemical fertilizers

Dang Yongfu has been hungry, and he has different feelings for grain.

In 1989, when he was working at home, he used herbicide herbicide for the first time, and the effect was amazing, but the crops experienced an inhibition period of 10 to 15 days after application, which was not long and turned yellow, reducing yield by 10 to 30%. Ever since that crop was harvested, he began to think about overcoming the side effects of herbicides.

Over the next few years, he used to find something to sprinkle in the ground, trying to neutralize the harm of herbicides. In 1995, Dang Yongfu went to Shenyang Chemical Research Institute and asked Professor Chen Chang to help him treat the side effects of herbicides. Professor Chen Chang suggested that it would be better to adapt to the situation and open your own herbicide factory. In 1996, the factory was built, but Dang Yongfu flatly shut it down and not a single drop of herbicide was produced. Because the more he inspected, the more afraid he was, worried that the factory would cause serious pollution to the local area.

Helpless and moved, Chen Chang decided to help Dang Yongfu build a pharmaceutical factory. The raw materials were first available, but Chen Chang died in 1997. But it is this pile of raw materials and the purification ideas left by Chen Chang that have become the starting point of Dang Yongfu's scientific research. Dang Yongfu began the "long March" in the field of degradation residues.

By 2003, Dang Yongfu had completed the accurate quantification of the main degradants. After that, the harm of herbicides was exposed in some parts of the northeast. Due to the excessive use of herbicides by farmers for many years, many plots have become "dead places", making it difficult for crops to survive, and people call them "cancer fields". Dang Yongfu took his products to Suihua, Heilongjiang, where the local plant protection station did not trust: "German companies have not been cured, and the cost is too high. Why should you?"

The old party relied on the effect, and the "cancer field" grew corn and soybeans again. In this way, he took "Nai'an" all the way north and traveled all over Heilongjiang, which is almost a household name in the countryside.

In this process, the old party found problems in the application of chemical fertilizer. The masses complain that chemical fertilizers are "boring", but the increments of chemical fertilizers do not increase grain. It takes 1.55 tons of coal to produce 1 ton of nitrogen fertilizer. Over the past 20 years, the use of chemical fertilizer per mu has increased by 12 to 15 times, and the yield per mu has only increased by about 40%.

In the old party's view, Henan has a period of eight months of accumulated temperature, has the best soil quality, and should theoretically be able to grow the best wheat in the world. However, chemical fertilizer dependence causes soil consolidation and acidification, the content of organic matter in the soil is seriously declining, and the plants grown are naturally not strong enough.

By chance, they cultivate microorganisms to secrete polyglutamic acid, which is purified in batches and reduces costs. Starting from here, the old party has found a feasible path for soil remediation, fertility activation, heavy metal passivation, pesticide residue degradation, and three-dimensional treatment of diseases, insect pests and weeds.

There is a long way to go, and it will take time for farmers to accept new soil remediation products.

The improved and restored land proves that these degradation enzymes and polyglutamic acid used for land restoration are really good things. Li Rong said, "this is exactly the technology our country needs. It can adjust both acid and alkali, and can solidify heavy metals." It has shown remarkable effects of losing weight, increasing production, improving quality and increasing efficiency on more than 10 kinds of crops, and occupies the leading level of similar products in the world in terms of technology. "

However, good things may not be accepted. Dealers were the first to resist, and Dang Yongfu was chased and beaten by dealers. Dealers welcome new applications of chemical fertilizers such as soil testing and fertilization and formula fertilization, but do not welcome the technology of fertilizer reduction. Even though polyglutamic acid can reduce costs, increase yields and repair soil, it still encounters rejection from time to time.

Under the action of polyglutamic acid, the amount of chemical fertilizer per mu can be reduced from more than 100 jin to less than 70 jin, and the cost of carbon adsorbed polyglutamic acid organic water-soluble fertilizer is about 30 yuan, and the yield can be increased. According to a relatively conservative assessment by experts from the Ministry of Agriculture, this technology can increase grain production by 8% with a 30% reduction in chemical fertilizer. But farmers' concept of "more fertilizer and more grain" is deep-rooted, and they want to be more high-yielding, and they are not willing to reduce the amount of grain.

In the large plots of land in Northeast China, farmers have a high acceptance of carbon-adsorbed polyglutamic acid organic water-soluble fertilizer, and the big grain growers in the mainland accept it quickly. However, if this new fertilizer is not used well, the harvest of one season may fail, and it is not cost-effective to trade high-risk for an increase of two or three mu of land.Therefore, small farmers who abuse chemical fertilizer most seriously are slow to accept it.

For farmers, the degradation of heavy metal passivation and pesticide residues has little to do with the immediate benefits, and one more degradation process means higher costs, but its effectiveness is difficult to be intuitive, and the market may not recognize it. Therefore, even with such good technology, they are not enthusiastic.

China has set the goal of zero growth in the use of chemical fertilizers and pesticides by 2020, but it is difficult to achieve the goal. As experts say, good technology still faces a lot of practical constraints and has a long way to go if it wants to be applied on a large scale.