1. Cultivated land area
In ancient times, Tongchuan was sparsely populated and was once a place with dense vegetation and lush forests. By the Spring and Autumn Period, the ancestors in the Tongchuan area were still mainly nomadic and also engaged in farming. According to the "Tongchuan Land Resources", by the fifth year of the Eastern Han Dynasty (29 AD), Ma Yuan was in the Sanfu region (Guanzhong) Tuntian, tongchuan was also among the tuntian, and the cultivated land area gradually increased. After the Western Jin Dynasty unified China, Emperor Wu of jin adopted the propositions of Fu Xuan (傅玄), a native of Niyang in the north (傅家原村; in present-day Guanzhuang Town, Yaozhou District, then Yushi Zhongcheng) to reduce taxes, build water conservancy projects, reclaim land, verify land acres, and punish officials who were not diligent in agricultural affairs. By the Ming and Qing dynasties, the land reclamation area reached its peak, and the sichuan, in situ and more than half of the gentle slope land had been reclaimed. The Ming Dynasty was still in Tongchuan, and according to the Republic of China's "Tongguan County Chronicle", "Mingcha Beishan Place Guardhouse, Military Land Tuntian, Early Qing Dynasty Cut and Tuntian Scattered People's Field, is the People's Tun Land."
Due to the alternating influence of stability and war disasters in the entire feudal society throughout the dynasties, the population is changeable, and the cultivated land is more and less. Tongchuan is multi-lineage mountainous, land resources are rich, but the distribution of cultivated land is relatively scattered, the soil is more barren and poor, especially in the northern mountainous areas, cultivated land is abandoned when cultivated, it is difficult to measure. In the long feudal society, the ruling class, due to the need for taxation, conscription, and conscription, had long ago begun to count the population and acres. Due to its long age, before the Ming Dynasty, the cultivated land area of Tongchuan was not examined. It was not until the late Ming Dynasty that there were more detailed figures. According to the "Land History of Tongchuan City", there were 259,000 mu of arable land in Yaozhou during the Ming Dynasty and 213,500 mu in Shiyao County of the Republic of China; during the Ming Dynasty, Yijun County had 336,000 mu of arable land, Qing Yongzheng had 574,700 mu of cultivated land, during the Republic of China (1937) there were 410,000 mu of cultivated land; during the Ming Jiajing period, Tongguan County had 594,000 mu of cultivated land, and later due to war and famine, farmers fled, the population plummeted, and the land was barren. In the tenth year of qing guangxu (1884), Tongguan County had 162,000 mu of civil land. In the twenty-fourth year of the Republic of China (1935), there were many foreign people migrating, the wasteland was reclaimed, and the people's land increased, and in the thirty-first year of the Republic of China (1942), the county's civil land was 352,100 mu, with an average of 6.41 mu.
After the founding of New China, after the land reform and the investigation of land and the determination of production, along with the stability of society and the restoration of the economy, the productive forces were greatly liberated, and the abandoned and deserted cultivated land was reclaimed, and many wastelands were reclaimed, and the area of cultivated land increased. In 1953, the cultivated land area of Tongchuan County was 419,200 mu, an increase of 15.54% over the 356,500 mu in 1949, and then with the occupation of cultivated land by urban and rural construction, the area was correspondingly reduced, and by 1974, the cultivated land area was 328,600 mu, and the per capita agricultural area was 3.76 mu. After 1980, Yao County and Yijun County were successively placed under the jurisdiction of Tongchuan City, with an area of 1.3026 million mu of arable land and 3.12 mu of agricultural per capita. In 1990, the city's cultivated land area was reduced to 1,179,100 mu. In 2000, it was 1,050,900 mu. In 2010, it was 940,600 mu.
Statistics of cultivated land area in some years of The Ming, Qing and Republic of China periods of Tongguan, Yaozhou and Yijun
Table 1-1 Units: 10,000 acres
| project name dynasty | Arable land area | Description | |||||
| Total | Among them | Household average (mu) | Per Capita (Mu) | ||||
| Officialdom | Civil land | ||||||
| Ming dynasty | Tongguan County | 59.40 | 0.38 | 59.02 | 64.5 | 17 | Jiajing time |
| Yaozhou | 25.98 | 113.9 | 12.25 | ||||
| Yijun County | 33.60 | 80.38 | 7.5 | Wanli | |||
| Qing Dynasty | 66.62 | 101.79 | 21 | Qianlong time | |||
| 57.47 | 60.65 | 12.14 | Yongzheng Shi | ||||
| Republic of China | 38.04 | 40.18 | 7.17 | 1931 to 1937 | |||
| 21.35 | 19.78 | 3.76 | 1937 to 1939 | ||||
| 41.00 | 3.70 | 37.70 | 44.05 | 9.28 | In 1937 | ||
| 100.39 | 36.76 | 7.75 |
Source: (1) Qiao Sanshi's "Yaozhou Zhi" (2) Tongguan, Yijun County Chronicle. (3) Tongchuan Land Information
Statistical table of cultivated land area in Tongchuan City from 1949 to 2012 in some years
Table 1-2 Units: 10,000 acres
| year | Arable land area at the end of the year | |||||||
| City-wide total | Yaozhou District (Yao County) | Printing station area (Suburbs) | Wang Yi District (Urban Area) | New | Paddy fields in the city total | The total amount of water and land in the city | ||
| 1949 | 149.61 | 69.55 | 44.41 | 35.65 | - | 0.04 | 0.58 | |
| 1953 | 170.24 | 81.25 | 47.80 | 41.19 | 0.21 | 1.32 | ||
| 1961 | 153.10 | 74.97 | 43.27 | 34.86 | 0.35 | 2.44 | ||
| 1965 | 166.01 | 74.42 | 55.13 | 36.46 | 0.27 | 2.05 | ||
| 1970 | 147.90 | 70.84 | 42.62 | 34.44 | 0.22 | 8.39 | ||
| 1975 | 135.79 | 66.67 | 36.15 | 32.97 | 0.23 | 9.57 | ||
| 1980 | 130.26 | 64.12 | 36.30 | 31.84 | 0.08 | 12.91 | ||
| 1985 | 121.73 | 60.63 | 31.64 | 29.46 | 14.00 | |||
| 1995 | 113.70 | 57.43 | 29.10 | 20.03 | 7.02 | 6.60 | 0.14 | 15.54 |
| 1996 | 111.68 | 57.23 | 28.78 | 18.68 | 6.98 | 6.54 | 0.13 | 13.79 |
| 1997 | 110.94 | 57.07 | 28.25 | 18.64 | 6.97 | 6.45 | 0.11 | 13.58 |
| 1998 | 110.29 | 56.81 | 27.82 | 18.65 | 7.00 | 6.23 | 0.10 | 13.61 |
| 1999 | 107.99 | 49.05 | 27.36 | 18.59 | 6.94 | 6.05 | 13.33 | |
| 2000 | 105.09 | 48.48 | 25.81 | 18.09 | 6.77 | 5.93 | 0.17 | 12.78 |
| 2001 | 96.54 | 45.21 | 23.79 | 17.56 | 5.76 | 4.21 | 0.18 | 11.94 |
| 2002 | 97.25 | 46.81 | 23.08 | 17.52 | 5.83 | 4.01 | 11.92 | |
| 2003 | 95.48 | 58.31 | 37.04 | 19.73 | 3.90 | 11.29 | ||
| 2004 | 95.93 | 46.65 | 22.56 | 17.17 | 5.68 | 3.85 | 12.27 | |
| 2005 | 96.39 | 46.99 | 22.66 | 17.29 | 4.02 | 12.35 | ||
| 2006 | 96.75 | 47.71 | 22.69 | 16.80 | 5.58 | 3.96 | 8.43 | |
| 2007 | 95.79 | 47.56 | 22.89 | 15.76 | 5.59 | 3.98 | 0.15 | 8.61 |
| 2008 | 93.01 | 47.52 | 23.22 | 13.11 | 5.60 | 3.51 | 7.06 | |
| 2009 | 93.90 | 47.45 | 24.20 | 12.76 | 5.10 | 3.52 | 8.34 | |
| 2010 | 94.06 | 25.66 | 12.90 | 2.02 | ||||
| 2011 | 94.98 | 47.51 | 26.77 | 13.27 | 5.84 | 1.59 | 8.65 | |
| 2012 | 94.86 | 43.33 | 28.70 | 13.39 | 5.61 | 0.09 | 10.91 |
2. Types of cultivated land
In the Republic of China and before, in order to facilitate the payment of land endowments and land rents, the county government divided cultivated land into 10 grades: upper flat land, middle flat land, lower flat land, in situ land, ditch land, terrace land, slope land, high slope land, mountain land, and beach land. After the founding of New China, after land reform and the inspection of land and production, the land grade was further verified, and the cultivated land was divided into 5 grades and 14 grades.
In 1984, a census of the city's land resources was conducted, and it was found that 1,752,900 mu of agricultural land in the city (including deforestation and grassland destruction, abandoned arable land and some underreported areas), accounting for 29.89%; forest land was 1,698,600 mu, accounting for 29%; grassland was 1,660,000 mu, accounting for 28.31%; garden land was 40,000 mu, accounting for 0.69%; water area was 89,400 mu, accounting for 1.53%; other land area was 622,200 mu, accounting for 10.6%; agriculture, forestry and animal husbandry land. It accounts for more than 85% of the total land area. The ratio of the three is basically 1:1:1. The agricultural land and in situ are mainly distributed in the southern Taiwon Chuandao district and the central and eastern remnants of the plains and ravines. The forest and pasture land is mainly distributed in the mountainous areas of the northwest.
In 1996, a detailed survey of the city's land was carried out, and the total cultivated land in the city was 1.8367 million mu, which was 657,200 mu more than the area (area used in the statistical annual report), an increase of 35.78%. Among them are a considerable number of wastelands reclaimed by deforestation and grass destruction.
Among the cultivated land, there are 891,200 mu of cultivated land on slopes, accounting for 50.8% of the total cultivated land, of which 216,000 mu, accounting for 12% of the slope land above 25 degrees; 764,700 mu of in situ land, accounting for 43.62%; 97,000 mu of Sichuan land, accounting for 5.54%; 342 mu of paddy fields, 143,700 mu of watered land, accounting for 12% of the actual cultivated land area, most of which are distributed in Yaozhou District. Dryland is the largest type of cultivated land in the city, with an area of 1,062,900 mu, accounting for 88% of the actual cultivated land, and is one of the areas with a relatively concentrated concentration of arid arable land in the province.
The city's vegetable land totals 12,754.3 mu, accounting for 0.7% of the cultivated land. Distributed in each district (county) 25 townships (towns) of the Chuandao, of which Yaozhou District is the largest area, totaling 7240.6 acres, accounting for 56.8% of the city's vegetable field area, concentrated in Yaozhou District Sigou, Chengguan and Xiagaobu, is the main vegetable production base in Tongchuan City. It is followed by Yintai District, with an area of 2971.4 mu, accounting for 23.3% of the city's vegetable field area, mainly distributed in Yintai, Laterite, Guangyang and Gaolouhe townships (towns). The vegetable field in Wangyi District is 2344.2 mu, and the area of Huangbao is the largest, accounting for 67.8% of the vegetable field in the district, followed by Wangjiahe Township and Wangyi Township. Yijun County is only 198.1 acres, mainly distributed in Wuli Town and Biaoqiao Township.
There is a lot of arable land on the slope of Tongchuan, how much rain there is in summer and autumn, and the soil erosion is serious, and the agricultural proverb once said: "Copper shines on dung, and Fuping Zatun" is difficult to cultivate. In order to change the farming conditions and control soil erosion, since the founding of New China, especially in the 1970s and 1980s, the city has built a total of 229,600 mu of horizontal terraces, 22,800 mu of river dam land, 257,100 mu of horizontal land, 0.65 million mu of river channel land, and a total of 516,000 mu of "four fields". The hierarchical distribution area of cultivated land slope in Tongchuan City is shown in the table:
Table of hierarchical distribution area of cultivated land slope in Tongchuan City
Table 1-3 Units: Acres
| City-wide | City district (present-day Wangyi District) | Suburbs (Present-day Intai District) | Yao County (present-day Yaozhou District) | ||
| flat ground | <2° (Level 1) | 263231.2 | 5375.9 | 36366.9 | 152064.2 | 69424.2 |
| slope earth | 2°-6° (Level II) | sloping land | ||||
| Terraces | 502609.4 | 22163.2 | 80626.7 | 263868.9 | 136314.6 | |
| 6°-15° (Level 3) | 614409.1 | 9574.9 | 87062.2 | 228502.1 | 289329.6 | |
| 133826.4 | 39842.8 | 53380.7 | 25743.8 | 14859.1 | ||
| subtotal | 748235.5 | 49417.7 | 140442.9 | 254186.2 | 304188.7 | |
| 15°-25° (Level 4) | 219018.6 | 8175.5 | 31614.4 | 106203.2 | 73025.5 | |
| 35222.4 | 11033.5 | 17562.9 | 3860.4 | 2765.5 | ||
| 254241 | 19209 | 49177.3 | 110063.6 | 75791.1 | ||
| ＞25° (Level 5) | 64787.6 | 3387.8 | 35441.3 | 9203.9 | ||
| 3574.6 | 1742.1 | 16754.6 | 1832.5 | |||
| 68362.2 | 5129.9 | 37278.8 | ||||
| 1836679.3 | 101295.7 | 323004.4 | 817456.7 | 594922.5 |
3. Soil type
During the Republic of China period, tongguan divided soil measurement into three districts and four layers. Three districts: hillside area, plain area, river valley area; four layers are divided into loess layer, laterite layer, alluvial layer and weathering layer.
In the mid-1980s, the Tongchuan Agricultural Department conducted a census of the city's soil. After the census, the soil was subdivided into 9 soil types, 15 sub-categories, 25 soil genera, and 73 soil species. The proportion of the nine soil types in the total soil area of the city is as follows: loess cotton soil area of 1704618 mu, accounting for 30.3%; black moorland soil area of 237780 mu, accounting for 4.32%; cinnamon soil 3021532 mu, accounting for 53.72%; new soil area of 113755 mu, accounting for 2.02%; marsh soil area of 85609 mu, accounting for 1.52%; fluvo-aquic soil area of 3502 mu, accounting for 0.06%; paddy soil area of 1557 mu, accounting for 0.03%; purple soil area of 1309 mu, Accounting for 0.02%; the area of red clay is 455396 mu, accounting for 8.1%. Its distribution law is from south to north, which is cinnamon soil, black moat soil and yellow cotton soil; the mountain valleys are mostly sandy loam new accumulation soil, sand and gravel new soil, loam new accumulation soil, alluvial new fluvo-aquic soil, and Hongshu type new fluvo-aquic soil; white soil and red clay soil are distributed in the remnants of Liang'an; black moorite and moorite soil are distributed in the original area; and sandstone mountains are distributed with sand and gravel brown soil and argillaceous rock brown soil. The city's soil is slightly alkaline, which is not only suitable for the growth needs of most crops, but also conducive to nitrogen-fixing fungi activities and can increase nitrogen fixation capacity.
List of soil types and distribution in Tongchuan City
Table 1-4 Units: 10,000 acres
| Type | Area | % of total land area | Distribution |
| Black mounds | 23.78 | 4.23 | It is distributed in all districts (counties) of the city. |
| Brown soil | 302.15 | 53.72 | It is mainly distributed in the middle and low mountains of the northwest. |
| Dirt | 8.56 | 1.52 | Mainly distributed in new areas. |
| paddy soil | 0.16 | 0.03 | It is mainly distributed in Yijun Chengguan, Shancha Gaoloutuo, Wuli Town and other townships (towns). |
| Yellow cotton soil | 170.46 | 80.3 | The distribution range is wide, from north to south, from remnants to ravines, from Taiyuan to gentle slopes. |
| Purple earth | 0.02 | It is mainly distributed in Kou Township, Yijun County. | |
| Red clay | 45.54 | 8.1 | The towns of Azhuang and Laterite in Yintai District, chengguan, Weeping Spring, Jiaoping, Gaolouyuan and other townships (towns) in Yijun County, and Gaoeryuan in Yaozhou District are scattered. |
| New soil | 11.38 | It is mainly distributed in the floodplains on both sides of the Qishui River, Depression River, Qingyu River, Zhao River, Huyu River, Wulizhen River, Qinghe River, Wangjia River, Leiyuan River and so on. | |
| Fluvo-aquic soil | 0.06 | It is distributed in Yijun County, Biqiao, Wuli Town, Leiyuan and Qipan Township. |
The cultivated layer of cultivated land in the city is generally 10 to 22 cm, the organic matter content is 1.02 to 1.3%, the total nitrogen content is 0.048 to 0.129%, the average is 0.078%, and the total phosphorus content is 0.1 to 0.2%, and the highest is 0.73%; The total content is 1.16~3.19%. The cinnamon soil area is the largest, the soil layer is thin, the soil is loose, although the organic matter content is high, but the mineralization is low, it is difficult to use, and it is easy to lose after maturation, it is advisable to plant forests and grasses; the yellow cotton soil layer is deep, it is suitable for long tillage period, although it is appropriate to plant grain and fruit, but the organic matter content is generally low and the yield is not high. Overall, the city's arable land foundation fertility is low. The effective fertility is: the average content of alkaline nitrogen is 8.4 ppm, equivalent to 6.4 kg of pure nitrogen per mu; the average available phosphorus is 8.4 ppm, the amplitude is 2-65 ppm; the average content of available potassium is 169 ppm; and the average amount of soil cation substitution (fertility retention) is 14.4 mg/100 mg (mg), which is a medium fertility level. The trace elements required for crop growth are: Fe: 5.08-6.8ppm; B:0.17-0.21ppm;Mn:5.9-7.23ppm;Zn:0.48-0.59ppm;Cl:0.75-0.92ppm.
The ratio of carbon and nitrogen in the soil tillage layer is 8.3:1 (less than the standard of the most suitable 25:1), the ratio of nitrogen and phosphorus is 2.2:1 (suitable for 3:1), and the nitrogen supply intensity is 5.4. The soil organic matter is insufficient, the nitrogen deficiency area accounts for 15.77%, and the phosphorus deficiency area is 93.29%. Among the trace elements, there is a serious shortage of boron and copper, an appropriate amount of iron, a lack of zinc and manganese, and a low level of fast-acting nutrients.