What latitude is Xixian?

Henan is located in the middle and lower reaches of the Yellow River in the east of central China, with east longitude11021'~11639' and north latitude 3 1 23'~ 36 22'. The land area of the whole province is167,000 square kilometers, ranking 17 among all provinces and cities in China.

Henan is in the transition zone from the second step to the third step in China, and its position is moderate. On the national map, Henan occupies a central position in both political area and traffic status. With Henan as the center, Heilongjiang in the north, the Pearl River Basin in the south, the foot of Tianshan Mountain in the west and the coast of the East China Sea in the east, most of them span two or three provinces and regions. If Zhengzhou, the provincial capital, is the center, the north is far from Beijing, Tianjin and Tangshan, the south is far from Wuhan, the west is far from Guanzhong Plain, and the east is far from economically developed areas such as Shanghai, Nanjing and Hangzhou, the straight-line distance is mostly within 600-800 kilometers. Historically, Henan has always been the only place for Chinese people to pass from south to north and from west to east, and it is also a place where people of all ethnic groups have frequent activities and close contacts. Modern railway trunk lines such as Beijing-Guangzhou, Beijing-Kowloon, Jiaozhi, Longhai and Xinhe run through Henan. This superior geographical location and convenient traffic conditions have narrowed the distance between Henan and all parts of the country. Therefore, Henan is in a central position in both economic ties with the whole country and economic and technological exchanges with neighboring provinces and regions. Under the current situation of vigorously developing the socialist market economy and developing the central and western regions, it plays an important role in national economic activities, linking the east with the west and connecting the south with the north, which is incomparable to other provinces and regions.

Climatic characteristics

Henan is located in the north subtropical zone and warm temperate zone, with mild climate, abundant sunshine and precipitation, which is suitable for developing agriculture, forestry, animal husbandry and fishery. Its characteristics are: first, the transition is obvious and the regional differences are significant. Henan is located in the mid-latitude zone, and the Qinling-Huaihe line, which divides China into warm temperate zone and subtropical zone, just passes through Funiu Mountain Ridge and the main stream of Huaihe River in China. The north of this line belongs to warm temperate semi-humid and semi-arid areas, accounting for 70% of the total area of the province, and the south of this line is subtropical humid and semi-humid areas, accounting for 30% of the total area of the province. Climate has obvious transitional characteristics. Due to the influence of monsoon climate, the latitudes of north and south are different, and the topography of east and west is different. There are many heat resources in south and east, less in north and west, more in south and southeast, and less in north and northwest of Henan, so there are obvious regional differences in climate. Second, it is warm and moderate, with the advantages of north and south. Henan has a mild climate, with an annual average temperature of 12.8- 15.5℃, sunny winter in Leng Xia and distinct seasons. It has the characteristics of long winter, less rain and snow, short spring, dry and windy sand, abundant hot rain in summer, abundant sunshine in autumn and so on. Henan is located in the transition zone between warm temperate zone and subtropical zone, and the advantages of the two climatic zones, north and south, are beneficial to the growth of many plants. Third, the monsoon is remarkable and disastrous weather is frequent. Henan is bordered by the vast Eurasia in the west and the vast Pacific Ocean in the east. The temperature difference between sea and land is significant in winter and summer, and the wind direction changes obviously with the seasons. Monsoon climate is an advantage for agriculture, but it also has disadvantages, mainly instability, which is manifested in the uneven distribution of annual precipitation in time and space. Usually, the annual precipitation is mainly concentrated in summer, accounting for 45-60% of the annual precipitation, and the instability of precipitation is easy to cause drought and flood disasters.

Geomorphological features

With complex geological conditions, complete stratigraphic system and various structural forms, Henan is one of the provinces with superior geological conditions in China. The landform of Henan has two main characteristics: First, the terrain is high in the west and low in the east, with obvious differences between the east and the west. He 'nan is located in the transition zone of the second and third grade landform steps in China. Taihang Mountain, Xiaoshan Mountain, Xiong 'er Mountain, Songshan Mountain, Waifangshan Mountain and Funiu Mountain in the west belong to the second-class landform steps, while the plains, Nanyang Basin and hills in the east are the components of the third-class landform steps. The general trend of Henan topography is high ups and downs in the west and low levels in the east. From west to east, from Zhongshan to low mountains, and then from hills to plains. The difference between the highest point and the lowest point in Henan is 2390.6 meters. It is this terrain that makes most of the larger rivers in Henan originate from the western mountainous areas. Secondly, the surface morphology is complex and diverse, and the landform types such as mountains, hills, plains and basins are complete. Henan has complex and diverse landforms. There are not only high mountains, but also vast plains, rolling hills and basins surrounded by mountains. Various landform types provide favorable conditions for the all-round development of agriculture, forestry, animal husbandry, industry and mining in Henan. Henan mountains are concentrated in northwest, west and south Henan, with Taihang Mountain in the north, Tongbai Mountain in the south, Dabie Mountain and Funiu Mountain in the west. Most of the hills in Henan are rocky hills with long-term weathering and denudation in low mountains, and some of them are loess hills formed by cutting the loess plateau by running water. Hills and mountains are often distributed together, mainly in a few areas in northwest Henan, eastern margin of western Henan and eastern margin of southern Henan. Henan plain is widely distributed, vast and magnanimous. The central, eastern and northern plains of the province are alluvial from the Yellow River, Huaihe River and Haihe River, also known as Huanghuaihai Plain. It starts from the eastern foot of Taihang Mountain in the west and the mountainous area in western Henan, reaches the northern foot of Dabie Mountain in the south and reaches the provincial boundary in the east and north. With a vast territory and fertile soil, it is an important agricultural area in China. Nanyang Basin in the southwest is the largest intermountain basin in Henan Province, with obvious annular and stepped landforms, covering an area of about 26,000 square kilometers. The central part of the basin is flat and rich in water and heat resources, and many kinds of plants can grow and develop here.

Geological soil

Due to the influence of natural conditions such as climate, landform and hydrology, Henan Province has a long history of agricultural development, and there are many soil types, which are distributed as follows:

The alluvial plain of the Yellow River and Haihe River to the east of Beijing-Guangzhou Line and to the north of Sha Ying is the largest tidal soil area in Henan Province, and the floodplain of larger rivers in hilly areas is also generally tidal soil area. Henan fluvo-aquic soil can be divided into three soil genera: sandy soil, silt soil and mixed soil. Sandy soil is mainly distributed in the upper reaches of the Yellow River floodplain and near the main floodplain, and silty soil is distributed in the still water deposition area in the downstream or inter-river zone, and the two kinds of mixed soil are in between. Due to the long history of farming and reclamation, these areas generally lack organic matter and have low natural fertility. Because of water leakage and fertilizer leakage, the irrigation index and fertilization level are higher.

Huaibei Plain south of Shahe River and Heying River and Nanyang, Tanghe River, Xinye and Dengzhou on both sides of Tanghe River in Nanyang Basin are the distribution areas of Shahe black soil. In these areas, the soil is heavy, the water physics is poor, the drainage is not smooth, and the lower part is often blocked by Shahe, but the organic matter is high and the potential fertility is great.

Some counties in Xinxiang, Shangqiu, Kaifeng and Puyang on both sides of the Yellow River are the distribution areas of saline-alkali land. Because the salt content is too high, it affects the growth of crops, and the saline-alkali soil is barren and becomes saline-alkali wasteland. In the early days of the People's Republic of China, the saline-alkali land area was about 6 million mu. Later, due to improper irrigation, it increased to196130,000 mu in 0 year. After the 1970s, measures such as ditch digging and drainage were vigorously promoted, and now it has dropped to about 4 million mu.

Paddy soil is distributed in the alluvial plain south of the Huaihe River, Huaibin, Xixian and Zhengyang on the north bank of the Huaihe River, and on both sides of the lower reaches of the Tang and Baihe rivers in the province. Generally speaking, the paddy soil in Henan Province is low in organic matter content and its fertility level is not as good as that in the lower reaches of the Yangtze River, but it is still one of the high-yield soils in Henan Province.

The white clay terraces in the loess hilly area of western Henan, the vertical loess in the middle and upper part of gentle slope hilly area, the red clay in the high part of low mountain hilly area, and the oily loess in the transition area from Taihang Mountain to Funiu Mountain are all cinnamon soil. Some of these areas have good fertility, some are barren, arid and barren, but the soil erosion is serious, which is the main soil type that needs soil and water conservation measures.

Brown soil is distributed in the Zhongshan area of Taihang Mountain, where Qinling Mountain enters Henan Province (south of Lingbao), east to Songshan Mountain, southeast to Fangcheng North, and two overlapping Zhongshan areas: Xiong 'er Mountain, Songshan Mountain and Funiu Mountain. There is a great difference in layer thickness in these areas, and the soil layer is generally thin, which is forestry land and should be controlled for reclamation and rational utilization.

Yellow-brown soil is developed on the south slope of low mountain hills in western Henan and the north slope of Dabie Mountain, or the slope with slow slope erosion. It is a suitable soil for subtropical trees in Henan, especially economic trees such as tea tree and tung oil. However, the weathering and soil erosion of this low mountain and hill are serious. In addition, in the low hills of Nanyang basin and Xinyang area, Huanggang soil, which is cultivated by yellow brown soil or yellow cinnamon soil, is a sub-type of dry land soil, which is sticky, hard, easy to crack when dry, poor in air permeability, low in organic matter content, prone to drought and waterlogging, and is one of the low-yield soils in Henan.

To sum up, there are seven types of soil in Henan: yellow brown soil, brown soil, cinnamon soil, fluvo-aquic soil, black soil in Jiang Sha, saline-alkali soil and paddy soil. If classified by texture, their percentage in total cultivated land is: clay 47. 1, sandy 19.9, loam 15. 1, sandy bottom clay 14.0 and gravel 3.9.

By the end of 200 1, the whole province had jurisdiction over 17 provincial cities, 1 provincial cities, 2 1 county-level cities, 48 municipal districts, 89 counties, 2 123 townships and 48,000 administrative villages. The provincial cities are Zhengzhou, Kaifeng, Luoyang, Pingdingshan, Anyang, Hebi, Xinxiang, Jiaozuo, Puyang, Xuchang, Luohe, Sanmenxia, Nanyang and Shangqiu, Zhoukou, Zhumadian and Xinyang, and Jiyuan.

land resources

The total land area of the province is167,000 square kilometers, and Henan is located in the mid-latitude zone. Due to the comprehensive influence of geological, natural and socio-economic factors, Henan's unique land resources have been formed, and its main characteristics are as follows:

Land types are complex and diverse. Affected by natural factors, such as the transitional climate between the north and the south and the terrain difference between the east and the west, complex and diverse land types have been formed, which provides very favorable conditions for the comprehensive development of agriculture, forestry, animal husbandry and fishery and diversified management.

Flat land is slightly more than hills and mountains. Among the total area of the province, the hilly area is 74,000 square kilometers, accounting for 44.3% of the total area of the province, and the plain and basin area is 93,000 square kilometers, accounting for 55.7% of the total area.

The amount of land resources is limited. Henan accounts for 1.74% of the country's land and raises 7.5% of the country's population. The province's per capita land resources are only 0.07 hectares, which is less than the national average 1/4. Due to the large population base and the absolute growth, the situation of more people and less land is becoming more and more severe. Henan is one of the earliest agricultural development zones in China, with a high degree of land development and utilization. At present, the province's unused land area is 6.5438+0.67 million mu, and the available reserve land resources, especially the reserve cultivated land resources, are seriously insufficient.

Regional development conditions vary greatly. Influenced by complex landform, transitional climate, hydrology, soil and other natural factors, the geographical distribution of land resources in Henan Province shows obvious differences. Three-quarters of the province's cultivated land area is concentrated in the plain area, accounting for 55.7% of the province's total area, while the hilly land, which accounts for 44.3% of the province's total area, only accounts for 1/4. The development conditions of land resources in different regions are also obviously different. The Huang-Huai-Hai Plain in the east and southeast of Nanyang Basin has a good combination of water, heat and soil, which is the main part of agricultural agriculture in the province and the concentrated distribution area of irrigated land and paddy fields, with superior development conditions. The soil and water conditions in the hilly areas of western Henan and the marginal hilly areas of Nanyang basin are relatively poor, especially in most areas, which are the main dry farming areas in the province. It is difficult to develop land resources and the input-output ratio is low, which is suitable for the development of forestry and fruit industry. The humid hilly and mountainous areas in the south subtropical zone have good water and heat conditions and great potential for land development, which has superior conditions for developing subtropical forest and fruit industry.