Original title: The saline-alkali land in the past, the rice grain river in the present (theme).
Hu Shuwen, a returnee professor at China Agricultural University (subtitle).
People's ** overseas edition reporter Zhao Yongxin Gu Yekai.
In 1999, Hu Shuwen, who had obtained his Ph.D. in China, went to McMaster University in Canada for further study, and then conducted scientific research at the University of California, Irvine and the University of Akron.
After returning to China, out of love for the land, Hu Shuwen changed his research direction and deeply cultivated the management of saline-alkali land. After more than 10 years of painstaking research, he led the team to explore a whole-process and systematic saline-alkali land improvement technology system, with a total of more than 100,000 mu of severely saline-alkali land and 1.9 million mu of salinized medium and low-yield fields. Writing ** on the field, Hu Shuwen's footsteps never stopped.
At 7 o'clock in the morning, I took the high-speed train from Beijing, got off the train at Hohhot City, Inner Mongolia Autonomous Region at 9 o'clock in the morning, and went straight to the saline-alkali land of Tuoketuo County, stepped on the snow to inspect the soil situation, and discussed with local large planters to discuss the ...... of the treatment planThis is the schedule of Hu Shuwen's business trip, and it is also a true portrayal of his daily work.
Hu Shuwen is inspecting the growth of corn. Photo by Zhao Yongxin, reporter of the People's ** Overseas Edition.
The 55-year-old is a professor at the College of Resources and Environment at China Agricultural University, and originally focused on the research of polymer materials, but an unexpected discovery made him change his research direction and devote himself to saline-alkali land management. After more than 10 years of hard work, he led the team to explore a whole-process and systematic saline-alkali land improvement technology system to achieve "treatment in the current year, effective in the current year, and stable production in the current year". According to incomplete statistics, by the end of last year, the team had treated more than 100,000 mu of severely saline-alkali wasteland and improved 1.9 million mu of salinized low- and medium-yield fields.
Saline-alkali land, known as the "stubborn disease of the land", is difficult to manage, long and easy to repeat, and is recognized as a worldwide problem. As a layman who became a monk halfway, the difficulties encountered by Hu Shuwen can be imagined - what has supported him to this day?
I just love it. Hu Shuwen said, "I was born in rural Shandong, and I have been dealing with land since I was a child, and I know the meaning of land to farmers. I rejoiced to see them reap a good harvest in the improved saline land. ”
If the saline-alkali land can be improved into fertile land for more grain, it will be very valuable."
In 1999, Hu Shuwen received his Ph.D. degree from the Department of Polymer Chemistry and Physics, Institute of Chemistry, Chinese Academy of Sciences, and went overseas to study and work in the field of polymer materials. In May 2006, China Agricultural University invited him to return to China to engage in the development of green and efficient functional controlled-release fertilizer.
Hu Shuwen built an experimental base in the suburbs of Beijing, conducting research and trial production. Design the production line, build the pilot plant, adjust the process parameters, and improve the material formula ......After more than a year of research, we have developed a coated controlled-release fertilizer that has reached the international advanced level and promoted it on a small scale.
In this process, Hu Shuwen unexpectedly found that the yield increase effect of coated controlled-release fertilizer on salinized land was significantly better than that of control land.
It's so much fun! Hu Shuwen said, "China's saline-alkali land has a wide area and great development potential, if the saline-alkali land can be improved into fertile land for more grain, how valuable it should be!" ”
You are doing so well in controlled-release fertilizer, why do you want to change careers halfway? "It is difficult to treat saline-alkali land, and it is not easy to apply for research topics, so what should I do if I can't do it in the end?" ”
In the face of the doubts of his friends, Hu Shuwen did not waver and gradually shifted the focus of his research to saline-alkali land management.
On Hu Shuwen's desk, there is a thick book of "Soil Science". "To treat saline-alkali land, we must first understand its characteristics. I'm a layman in soil, but as long as I'm willing to learn, it's not a problem. In order to understand the saline-alkali land, Hu Shuwen humbly sought advice from colleagues in related majors while gnawing books and checking literature.
Why is it so difficult to desalinate saline-alkali land? After in-depth research, Hu Shuwen found the crux of the problem: the soil particles of sodium-alkali land are fine, there is no normal soil aggregate structure, and it is compact, dry and hard, impermeable to water and air, which makes it difficult to remove salt.
If we could invent a 'binder' to bind fine saline-alkali soil particles into large particles and improve the permeability of the soil, wouldn't the salt in it be easier to wash off with water? Hu Shuwen uses natural polymer materials such as cellulose, lignin, and chitin as the base, and uses calcium, magnesium and other elements for chemical modification, and develops and designs a soil conditioner, so that it can "catch" the surrounding fine particles and form soil aggregates, thereby changing the soil structure of saline-alkali land and improving the efficiency of desalination. For each amendment he designed, he sent samples to his friends in the agriculture department, who asked them to conduct small-scale experiments in saline fields, and then optimize them based on the feedback until the ideal improver was selected.
After several years of exploration, Hu Shuwen developed an amendment for different types of saline-alkali land. The test results proved that after using soil amendment, the desalination efficiency was increased by more than 10 times compared with the traditional method, and the water consumption was also reduced by more than 90%.
We must pull the research team into the field and do it in a down-to-earth manner."
Efficient desalination is only the first step, and the key is to make good crops grow in saline soil. Hu Shuwen said, "It's not enough to just make models and 'potted plants' in the laboratory, you must pull the research team to the field and do it in a down-to-earth manner." ”
Since 2012, Hu Shuwen has carried out field experiments on improved saline-alkali land in Chifeng, Inner Mongolia, and other places, during which the yield of crops such as sugar beet, sorghum and corn has increased significantly.
Immediately afterwards, Hu Shuwen decided to gnaw on the "hardest bone" - the soda saline-alkali land in the western part of the Songnen Plain. It is one of the world's three major soda saline-alkali land concentrated distribution areas, with saline-alkali coexistence, soil compaction, poor permeability and poor nutrients.
In the spring of 2015, Hu Shuwen led his students to take root in a piece of saline-alkali land in Bamian Township, Tongyu County, Baicheng City, Jilin Province. Going to the ground, drilling the soil, digging the profile, measuring the soil sample, ......He and his students worked in the field for half a day, and their complexion became dark.
Farmer friends are the most down-to-earth teachers. Another thing Hu Shuwen did when he went to the field was to ask the local farmers for advice, "They have rich practical experience, are more familiar with the local climate and planting conditions, and have accumulated a lot of knowledge." Until now, Hu Shuwen has spent about half a year in practice. "You can only feel it when you go to the ground and touch your hands and feet. Hu Shuwen said.
Rooted in the land and working hard, humbly learning from the farmers, Hu Shuwen solved the problem of the growth of crops in saline-alkali land one by one in practice.
At the same time, Hu Shuwen also set his sights on interdisciplinary joint research. He said that saline-alkali land management is a multidisciplinary system engineering, and only by considering factors such as amendments, fertilizers, microbial communities, salt-tolerant crop varieties and water conservancy projects, and planting management can we explore a set of whole-process and systematic solutions to turn saline-alkali land into fertile land.
In the face of areas such as nutrition, microorganisms, crop varieties, and water conservancy engineering, Hu Shuwen invited colleagues from different departments of the school to work together to tackle key problems, and everyone showed their strengths to continuously improve the technical system of saline-alkali land treatment.
After long-term exploration, Hu Shuwen's team finally created an ecological restoration saline-alkali land system engineering technology system based on the principles of "soil remodeling, efficient desalination, combination of dredging and blocking, and reclamation of fertile land". He led the team to establish more than a dozen large-scale demonstration areas across the country, and the treatment results have been remarkable: the soda-shaped alkaline soil improvement demonstration field in the former Guoerlus Mongolian Autonomous County of Songyuan City, Jilin Province, the rice yield has been maintained at about 600 kg per mu for many years; In Linhe District, Bayannur City, Inner Mongolia, the seedling retention rate of sunflower was significantly improved, and the yield increased by 132% compared with the saline-alkali land improved by the original technology. On the saline-alkali land in Shuozhou, Shanxi, Yancheng, Jiangsu and other places, the output of dryland crops increased that year.
In the second and third years, the average local production ...... will be reached
What could be happier than being able to do something practical with your own expertise."
Hu Shuwen's busy footsteps did not stop. In the summer of 2022, he took his students to Xinjiang to conduct research. Xinjiang is the most widely distributed area of saline-alkali land in China, and it is of great significance to control saline-alkali land.
However, Hu Shuwen's research found that drip irrigation is commonly used in Xinjiang, and the original improver developed is a solid material that is incompletely soluble in water, which is easy to clog drip irrigation equipment. In addition, although the degree of soil salinization in Xinjiang is mostly moderate and mild, due to the dry climate, scarce precipitation and high evaporation, the method of washing salt with large water is simply not feasible.
After pondering all the way, Hu Shuwen came up with a solution: develop a water-soluble improver that does not clog the water pipes, and at the same time add a new function of water retention to the improver. Back in Beijing, he led the team to develop new functional water-soluble improvers.
In July 2023, he and his team came to Hotan, Xinjiang, with a newly developed improver, to carry out silage corn planting trials on newly reclaimed moderately and mildly salinized cultivated land. The results of field measurement showed that the yield of silage corn per mu in the improved group was 329238 kg, 60 more than the control group1%。Not only that, but the soil salinity was reduced by 62% compared to before the new amendment. In December 2023, the Aksu Prefecture Administration and China Agricultural University jointly established a saline-alkali land improvement laboratory to promote the technical achievements of Hu Shuwen's team on a large scale.
The saline-alkali land improvement model we have explored in Hotan, Xinjiang has broad prospects! Hu Shuwen said, "It is not only simple and easy, but also low cost, high income, a one-time investment of 200 yuan per mu, can increase the income of nearly 600 yuan that year." In the arid regions of northwest China, including Gansu, Ningxia and western Inner Mongolia, this method can be used wherever drip irrigation is used. ”
Since 2008, Hu Shuwen has been working on saline-alkali land for 16 years. His team has also increased from a few people to dozens of people, and has become a multidisciplinary scientific research team that combines the old, middle and young people in saline-alkali land management.
Mr. Hu's love for the cause of saline-alkali land improvement is almost selfless. This love is also infectious with other teachers and students in the team. Gao Haixiang, a professor at the College of Science of China Agricultural University, who has worked with Hu Shuwen for many years, said.
Hu Shuwen said: "What could be happier than being able to do something practical with your expertise?" ”
*: People's ** Overseas Edition.