Analysis of Unit System Standards for Measuring Land Area

"Mu" as a measure of land area can be said to be a long-standing history in our country. According to "The Mencius Liang Hui Wang Shang" records: five acres of houses, the tree is mulberry, fifty can be clothes. It can be seen that, at least in the spring and autumn, "Mu" has already been used as a unit of measurement. The ancients "established and established acres"
("Front Chinese book" volume 24), that is, the number of steps to calculate the number of acres. The size of the acre is different due to different dynasties.
For example, there was once a history of large, medium, and small acres: 100 acres of small steps, and weekly systems; 294 acres of medium-sized, and Chinese-made systems; 366 acres of large-scale, homogeneous systems ("urgent on the chapter") ). In addition, each step was six feet before the Tang and five feet after the Tang. Each foot length gradually increases from 19.9 centimeters in the Zhou Dynasty to 32 centimeters in the Qing Dynasty. Therefore, the actual area of ​​an acre in history is difficult to determine.
The city’s municipal acre was determined by the Nationalist government in 1929 with the provisions of the Qing Dynasty. In 1956, the State Council affirmed the use of the Mu system in the "Order for a Unified Metrological System." Therefore, the use of acres of units has been continued. With the continuous deepening of China's reform and opening up, the use of acres of units has brought more and more prominent problems. The main points are as follows:
1. Due to historical reasons and differences in local and customs, the actual amount of mu used in some areas of China is inconsistent with the prescribed amount. The actual use of mu is often greater than the prescribed value, the average national average is 30%, and individual regions are even 50-100% larger. According to the results of satellite surveys and sampling surveys, the total number of arable land in China is approximately 130 million hectares (2 billion mu), while the actual statistics are only 100 million hectares (15 million mu), which is 30 million hectares less than the number of surveys ( 500 million mu). This has brought serious difficulties to our country's taxation, statistics, planning and land management.
2. At present, 86 countries and regions in the world have adopted the International System of Units (sI). It has become international practice to measure land area in square meters and hectares. If we continue to use the Mu system, it will inevitably adversely affect China's foreign trade and international exchanges.
3. Mu system is derived based on the city length unit city scale. Due to the fact that the municipal length units have long been abolished, the mu-units can only be associated with metric units of length. In this way, the operation must be measured in length in units of metric lengths first, and then converted to municipal units. This not only adds an unnecessary process, but also makes errors in the conversion of the two units.
4. Since people are already accustomed to metric units, if one hectare is an area of ​​100 meters in length and width, the average size of the area can be imagined, and the area of ​​one mu of land is about 666.6 square meters. It is difficult to give an intuitive impression.
It can be seen that China's mu system should not continue to use it.
In 1984, China promulgated the "Statistical Measurement Unit of the People's Republic of China" and determined that the legal measurement unit for the land area of ​​China is hectares, but considering the specific circumstances of China at that time. The State Council, in issuing the order to implement legal measurement units, pointed out that the reform of units for measuring farmland land area should be based on investigations and studies to formulate reform plans and announce them separately.
In December 1990, the State Bureau of Technical Supervision, the State Bureau of Land Management, and the Ministry of Agriculture jointly issued the "Notice on Reforming the Measurement Unit of Land Area in the Whole Country." The notice pointed out: On July 27, 1990, the 65th executive meeting of the State Council decided to use square kilometers, hectares, and square meters as the units for measuring land area. On May 13, 1993, the State Land Administration Bureau issued a document stipulating that, since 1993, legal filing units should be used in principle in issuing documents, reporting on correspondence, publicity, and publication of books and textbooks.
The abolition of the mu system in China is an important measure for the implementation of reform and opening up and its integration with the international community. In recent years. The 100% use of the statutory land area measurement unit of the forestry industry has made great achievements. For example: "National Forestry Statistics" edited by the Ministry of Forestry (1 volume per year). Since 1992, all units of statutory land area have been used. Most of the forestry science and technology publications also use statutory land area measurement units. However, it should also be noted that there are still some issues that cannot be ignored in the use of statutory land area measurement units. At a national conference, the conference published a total of 34 written materials, of which only the communication materials of the Hebei Provincial Department of Forestry and the Songjianghe Forestry Bureau adopted a legal land area measurement unit. The rest of the materials involved in the measurement of land area units All use of acres of units. Some forestry newspapers and periodicals, publicity materials, and some documents that have been uploaded and distributed still have problems with the use of illegal land area measurement units to varying degrees.
The correct use of legal land area measurement units and the rational use of acreage measuring instruments and other advanced farmland area measuring instruments are not only a matter of implementing the relevant national laws and regulations, but also a concrete embodiment of our forestry industry's awareness of science and technology, and promoting the standardization and science of forest land resources. Management and the promotion of foreign economic and technological exchanges in the forestry industry should be given full attention by leaders at all levels and the majority of forestry workers.
The statutory land area measurement unit should be used correctly.

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