Are Beidahuang and Beidacang the same place?

Beidacang, Sanjiang Plain, Beidahuang, Heilongjiang and Northeast China are often called "Beidahuang", which refers to the vast barren areas of Nenjiang River Basin, Heilongjiang River Basin and Sanjiang Plain in Heilongjiang Province. More than half a century ago, it was a vast wilderness, sparsely populated, with dense forests, swamps everywhere, wild animals in the forest, and birds flying low. "Hunting roe deer for fish, pheasant flying into the rice cooker" was once a true portrayal of the ecological environment here. One of the precious resources of this wasteland is land, which is thick humus formed through thousands of years, that is, fertile black soil layer. The organic matter content of this soil is about 10 times that of loess, and it is the most fertile and suitable land for cultivation. It is one of the three black soil regions in the world, accounting for 1/5 of the total black soil region in the world. Why did Beidacang return farmland to wasteland? After the founding of New China, half a century's reclamation has made Beidacang an important national commodity grain base with an annual output of 7 billion kilograms. Among them, soybean production accounts for 37% of the national total output, and corn production accounts for 53% of the national total output, which has an irreplaceable position in China, which is why "Great Northern Wilderness" is also called "Great Northern Warehouse". Now, however, the embarrassment faced by Beidacang is that there are fewer and fewer black lands that it can be proud of. The data show that the organic matter content in the surface layer of cultivated land in the black soil area has dropped to 2.5% ~ 6.5%, which is more than half of the 1 1.8% at the beginning of reclamation. Due to excessive reclamation, the original ecology here has been seriously damaged. Nature has mercilessly issued a huge "ticket" to people-soil erosion, river flooding, wind erosion and desertification, abnormal climate, frequent droughts and floods, and reduced grain production. First, the soil erosion is shocking. The average annual precipitation in Northeast China is not much, but it is concentrated in summer, mostly in the form of heavy rain. Due to the destruction of surface vegetation, concentrated runoff and strong scouring power, the soil suffered from serious water erosion. When snow melts in spring, it will produce snowmelt runoff. When the black soil thaws, a layer of soil is washed away. This freeze-thaw erosion phenomenon is very serious, and its scouring speed is no less than the soil erosion caused by heavy rain. Nowadays, in places with serious soil erosion in the black soil area, we can actually see a scene similar to the unmanned Loess Plateau: large areas of fertile land are dismembered and fragmented, and the land in Ma Pingchuan is criss-crossed! It is estimated that nearly 30% of the black soil areas in Northeast China have different degrees of soil erosion. The black soil layer is lost at a rate of about 0.7 cm ~ 1 cm every year (and it takes 400 years to form the top soil of 1 cm), and the black soil layer has dropped from 80 cm ~ 100 cm at the beginning of reclamation to 20 cm ~ 30 cm. Experts predict that at this rate, most of the black soil layer will basically disappear after 50 years, and the rest will be loess-like loam. In this kind of soil, crops can hardly grow, and the black soil area in Northeast China will become a veritable "Great Northern Wilderness". According to the documents on the current situation of cultivated land in Heilongjiang Province, the nitrogen, phosphorus and potassium elements lost in the soil in this province are converted into millions of tons of standard chemical fertilizers every year, and the grain output is reduced by 2 billion to 4 billion kilograms due to soil erosion. Large-scale soil erosion has taken away a lot of nutrients from our scarce black land and greatly reduced soil fertility. Agricultural production has to use more and more chemical fertilizers, which in turn increases land pollution and intensifies soil hardening and degradation. Second, the ecological problems are getting more and more serious, and excessive reclamation has reduced the wetlands here by half. As "kidney of the earth", wetlands and forests can purify air and water, alleviate droughts and floods, detoxify and decompose wastes, help to increase and restore soil and its fertility, and stabilize local climate. These functions are weakened or almost disappeared, which makes the black soil area in Northeast China with pleasant climate become an ecologically fragile area: the frequency of climate anomalies is getting higher and higher, the types of natural disasters are increasing, and the scope and frequency of drought, flood and wind disasters are getting wider and wider. In this way, the northeast is also likely to become another wind source of sandstorms! Sediment produced by soil erosion is discharged and deposited on rivers, reservoirs and roads, resulting in frequent floods. Due to sediment deposition, 89 water conservancy projects have been scrapped in the West Liaohe River Basin. 1998 During the catastrophic floods in Songhua River and Nenjiang River basins, eight tributaries of Nenjiang River basin suddenly experienced flash floods, resulting in floods with super historical water level. Due to a large amount of sediment deposited in the riverbed, the Songhua River waterway has been shortened from 1500 km in the 1950s to 580 km at present ... Third, it is urgent to return farmland to "wasteland". People pay more and more attention to the serious soil erosion in the black soil area of Northeast China. Sustained large-scale soil erosion not only fundamentally destroyed the precious agricultural resources and ecological environment in the Northeast Plain, but also damaged the comprehensive agricultural production capacity of the "Northeast Granary". Faced with successive ecological crises and the punishment of nature, people in the Great Northern Wilderness understand a truth: to improve the ecological environment of the Great Northern Wilderness and realize sustainable development, there is no choice but to return farmland to forests and restore vegetation. In 200 1 year, the Heilongjiang Provincial Party Committee and the provincial government made a far-reaching strategic decision: stop reclaiming wetlands, return all the land unsuitable for cultivation to forests and grasslands, vigorously promote the natural forest protection project, and build a lasting "ecological barrier" for Beidacang. After several years' efforts, the Great Northern Wilderness has revived: in Sanjiang Plain, the number of wild animals has increased from 168 three years ago to 224 now, and some wetlands that disappeared in the past due to land reclamation have also begun to recover, showing a gratifying scene of rich water plants, birds singing in Luming Literature and frequent wildlife. While returning farmland to "wasteland", scientific biological measures were taken to increase the yield per unit area, and the improvement of ecological environment promoted the sustainable development of grain production. At present, it has formed a commodity grain production capacity with an annual output of 654.38+000 billion kilograms.