Over 40% of China's cultivated land has degraded, with pollution problems becoming even more severe
Recently, the Ministry of Agriculture held a national on-site meeting on farmland quality construction in Yangzhou, Jiangsu. At the meeting it was revealed that degraded farmland now accounts for more than 40% of total farmland area. Behind the decline in farmland quality, which factors cannot be ignored? How can farmland quality be protected to ensure national food security?
“Red line” and “bottom line”:
Establish the concept of “giving equal weight to quantity and quality” in farmland resources
“Ten years ago, this land was still very good; you could plant anything. But in recent years, for some reason, ‘it is hard as a rock on sunny days, and water will not soak in on rainy days.’ Now we can only grow some hardy potatoes and interplant a bit of corn.” After the autumn harvest, Chen Wanfu, a villager from Zhangguan Village, Xiaoguan Township, Xuan'en County, Hubei, was preparing to level the several mu of farmland his family owns. He picked up a handful of compacted clods of soil and said with emotion.
⟦NL> At the Soil and Fertilizer Workstation of the Hubei Provincial Department of Agriculture, researcher Liang Huadong showed a chart titled “Soil Survey and Land Fertility Evaluation.” The chart shows that among Hubei's current farmland, high-yield fields with an annual grain yield of more than 800 kg per mu account for only 26.1%, while medium- and low-yield fields account for 73.9%. Thirty years ago, according to the nine-grade farmland classification method, among Hubei's 50 million mu of regularly cultivated land, first- and second-grade land exceeded 60%. Today, the area of first-grade land has decreased by 28.14%, while the area of poor-quality farmland has increased rapidly, with sixth-grade land more than tripling.
Behind the data is the reality of declining farmland quality in our country. National farmland quality monitoring results show that in the black soil region of Northeast China, the organic matter content of farmland soil has dropped sharply, with an average content of 26.7 grams per kilogram, a decrease of 31% compared with 30 years ago. The black soil layer has fallen from 80 cm to 100 cm at the early stage of reclamation to 20 cm to 30 cm, and in many places the yellow soil is already exposed.
“At present, secondary salinization is severe in the Huang-Huai-Hai Plain of our country, the fertility of the black land in Northeast China is declining, and soil organic matter is dropping rapidly. In the Northwest, farmland soil degradation caused by soil erosion, and in the central-southern red soil areas, infertility, acidification and heavy metal pollution of soil are relatively serious, while the quality of newly added farmland is low.” pointed out Zhou Wei, a researcher at the Institute of Agricultural Resources and Regional Planning of the Chinese Academy of Agricultural Sciences.
The decline in farmland quality poses a certain threat to stable grain production and has also sounded an alarm for the country's food security issue. “In order to ensure our country's future food security, the state has already clearly proposed a ‘red line’ of no less than 1.8 billion mu of farmland area, but this is only a quantitative concept and is far from enough. While ensuring the quantity of farmland, we must vigorously strengthen farmland quality construction and hold the ‘bottom line’ of farmland quality; this is equally significant.” said Chen Wenfu, an academician of the Chinese Academy of Engineering.
Insufficient soil fertility and worsening pollution:
Control non-point source pollution to achieve “storing grain in the soil”
On the one hand, the basic soil fertility of our country's farmland lacks staying power; on the other hand, the problem of worsening land pollution is becoming more and more serious.
According to statistics, our country's farmland area is less than one tenth of the world's, yet it uses nearly four tenths of the world's chemical fertilizers. At present, our country's pesticide use has reached 1.3 million tons, 2.5 times the world average.
“From a scientific perspective, 70% to 80% of grain output should rely on basic soil fertility, and 20% to 30% on water and fertilizer inputs, while the contribution rate of our country's basic farmland fertility to grain output is only 50%. Land degradation caused by industrial waste pollution, chemical fertilizer and pesticide pollution, and seed product pollution is serious.” Zhou Wei said.
Experts say that at present our country's chemical fertilizer use level is already very high. Affected by the law of diminishing returns, the output increase that can be brought about by increasing chemical fertilizer input is near its limit. In the future, the model of relying solely on increasing inputs of agricultural chemicals and energy should be changed. By controlling agricultural non-point source pollution, improving the basic fertility of farmland, and storing grain in the soil, this is the inevitable choice for establishing a long-term mechanism for our country's future food security and realizing food security guarantees.
In order to promote the protection and improvement of farmland quality, this national on-site meeting on farmland quality construction proposed that in the future it is necessary to comprehensively improve the level of field facilities and the basic fertility of farmland, improve the farmland quality environment, and ensure that by 2020, 800 million mu of contiguous, high-standard farmland that yields stable harvests despite drought or excessive rain will be built, soil organic matter content will be increased by 0.5 percentage points, the utilization rate of organic fertilizer resources will be increased by 20 percentage points, straw return will reach 80%, and zero growth in pesticide and chemical fertilizer use will be achieved.
Balancing the present and focusing on the long term:
Establish a long-term mechanism for farmland quality protection
⟦NL> “Before 2011, this place was 1,300 mu of abandoned facilities such as homesteads, roads and ponds left after four villages relocated. After three years of reclamation and consolidation, these lands became farmland after reclamation and, together with the surrounding farmland, formed a contiguous area of 10,500 mu. After comprehensive management and the application of good seeds and good methods, they have become high-standard farmland with stable yields despite drought or excessive rain. This year the rice yield here reached 1,300 jin per mu.” said Liu Yan, deputy station chief of the district soil and fertilizer station, at the rapid fertilization project area for reclaimed land in Huaishi Town, Hanjiang District, Yangzhou City, Jiangsu Province.
Zeng Yande, director of the Planting Industry Department of the Ministry of Agriculture, said that to improve farmland quality, attention must be paid to balancing the present and the long term, coordinating production and ecology, engineering and techniques, and agricultural machinery and agronomy, and making efforts in several aspects such as improving obstacle soils such as acidified and salinized soils, building up soil fertility, retaining water and fertilizer, and pollution control and remediation.
Chen Wenfu pointed out that in the future it is also necessary to explore and promote the establishment of compensation policies for farmland construction and protection, so as to provide financial guarantees for farmland quality construction. It is suggested that the state, on the basis of using no less than 15% of land transfer revenue for agricultural land development, add more than 30% to establish a special fund for improving the quality of existing farmland, to be used for straw return, increased application of organic fertilizer and soil amendments, and other measures to build up soil fertility.
At present, our country has no specialized laws or regulations on farmland quality management, only some principled provisions in the Land Administration Law and the Regulations on the Protection of Basic Farmland. Due to the lack of corresponding laws and regulations on farmland quality management, it is difficult to exercise control over farmland quality, and it is difficult to impose timely and effective penalties for acts that damage farmland or cause a decline in farmland quality. In this regard, experts suggest that while implementing farmland quality construction actions, work on designating permanent basic farmland should be done well, the farmland quality monitoring system should be strengthened, the legislative process for farmland quality protection should be accelerated, and farmland quality protection should be brought onto a track of normalization, legalization and standardization.