The main point is that cities play a leading role in regional economic development, and the promotion of cities to regional economy is inversely proportional to spatial distance. The development of regional economy should take the city as the center and gradually develop outward, which has the characteristics of annular and layered spatial distribution.
A city is a constantly changing regional entity. On the surface, it refers to the actual scope of social and economic activities with a fairly non-agricultural population. The city has a close relationship with its surrounding areas.
The role of cities in the region is restricted by the law of "distance attenuation" of spatial interaction, which will inevitably lead to the formation of a circular layered spatial distribution structure with the built-up area as the core. From the built-up area to the periphery, from the urban core to the suburbs, various lifestyles, economic activities and land use patterns change regularly from the center to the periphery.
Extended data:
The application of administrative circle structure theory;
The theory of administrative circle structure is to divide a country's central administrative region and marginal administrative region into several types according to the relationship with the central government or superiors, which can be divided into corresponding geographical distribution space or political structure space.
It can also be subdivided into several sub-circle layers or sub-circle layers. We divide circles according to road distance, political control, economy, nationality and culture.
First of all, the distance within the road is the basic basis for us to divide the administrative circle. Without geographical boundaries, no administrative region can exist. Different types of administrative regions must have different regional support. The early administrative circle or macro-administrative circle is closely related to geographical space, such as the Yugong Five Affairs Circle mentioned above.
Secondly, political control is the direct basis for us to divide administrative divisions. According to my observation, countries throughout the ages, except pocket countries, basically have two types of circles: central area and marginal area. However, in countries with great cultural differences (such as China, a multi-ethnic country), the circle can be further refined.
For example, the central area can include two sub-circles, namely, autonomous regions and general administrative regions, while the peripheral areas include two sub-circles, namely, autonomous regions and vassal States. The density of the relationship between different administrative regions and the central government is different, which is generally manifested in the degree of autonomy, which is the standard to judge the nature of each administrative region. The higher the degree of autonomy.
The rarer the relationship with the central government or superiors; The lower the degree of autonomy, the closer the relationship with the central government or superiors. In multi-ethnic countries, the former mainly refers to the types of vassal countries and autonomous regions, which mostly appear in marginal areas; The latter mainly refers to the types of ordinary administrative regions and direct jurisdiction, which mostly appear in the central area.
Third, economic strength, ethnic distribution and cultural identity are also important references for us to divide circles. With the change of national territory, the imbalance of economic development, and the influence of ethnic migration and cultural exchange, some administrative regions that were originally in the central area often moved out (such as counties directly under the jurisdiction of new monarchs in various countries during the Spring and Autumn Period and the Warring States Period).
Most of them are distributed in the border areas of the country; Sanquan County, which was directly under the jurisdiction of the Song Dynasty, is located in the Qinba Mountain area), and the ethnic autonomous regions that were originally in the marginal areas often moved inward (for example, the Tangut Qiangjimifu prefecture in the northwest of the Tang Dynasty moved to Guanzhong and Shannan areas; Jimizhou, a miscellaneous state in the northeast, moved to Hebei and Henan, and there was a phenomenon of "breaking" in geographical space.
The so-called fracture phenomenon seems to be the fracture of the geographical circle, but it actually follows the internal evolution logic of the administrative circle structure. As mentioned earlier, the core of the administrative circle structure is the relationship between the central area and the peripheral area, not the form that the central area must be inside and the peripheral area must be outside.
From this perspective, although the geographical circle will be broken, the political relationship with the central government has not changed. The two circles, the central area and the peripheral area, and even several sub-circles, are completely different in various administrative types. Therefore, breaking the phenomenon only enriches the content of the circle.
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