1 Overview of the study area
Shawan County is located in the southern margin of Junggar Basin, on the west bank of Manas River on the northern slope of Tianshan Mountain. It is bounded by 84 57 ′ ~ 86 09 ′ east longitude and 43 20 ~ 45 56 ′ north latitude. It is narrow from east to west, the widest 10 1 km, and the longest from north to south is 280 km. The total area of the county is 13 1 10 square kilometers. The terrain inclines from south to north, and the Eurasian Continental Bridge, National Highway 3 12, National Defense Highway, Hook Highway and Wukui Expressway pass through the territory, which is 0/85km away from Urumqi/KLOC-0, the capital of the autonomous region. The traffic is convenient and fast, and it is the main traffic artery from Urumqi to northern Xinjiang. Shawan County has jurisdiction over 9 towns including Sandaohezi Town, Wulan Wusu Town, Dongwan Town, West Gobi Town, Anjihai Town, Sidaohezi Town, Laoshawan Town, Jingouhe Town, Liumaowan Town, Daquan Township, Merchants Township and Botong Ancient Town. 3 townships; Niuquanzi Ranch, Bortonggu Ranch and Caojiapo Ranch; State farm; That is, the seed field; Plain forest farm; Sandaohezi Forest Farm; 242 administrative villages. Total population196820 (5438+0 in May 2006), of which agricultural population 14 169 1, accounting for 75.08% of the total population; There are 12 1 regiment, 122 regiment, 132 regiment, 133 regiment, 134 regiment, 135 regiment and/kloc-0 regiment in China. There are 15 1 etc. 12 farms with a population of 2 17 172 (provided by the Bureau of Statistics in May 2006, 5438+0). There are 25 ethnic groups in the county, including Uygur, Kazak, Han, Hui and Mongolian. In 2000, the total land area of Shawan County was 65,438+0,267,657.75 hectares, including 65,438+0,926,865,438+0.34 hectares of cultivated land (including Corps), 265,438+0.64 hectares of garden land and 62,338 hectares of woodland.
2 technology and methods to find location factors
2. 1 position coefficient
Location factors reflect the distance and relative position between land and cities (towns), villages and towns, and the relative position with administrative and economic centers. For agricultural land, it is an important factor that determines the direction of land use, intensive use and land productivity. Location factors can be expressed by the influence of central cities, the influence of farmers' markets, the accessibility of roads and the convenience of external transportation. Liumaowan Township and Sidaohezi Town in Shawan County are greatly influenced by Karamay City, and Huck Highway runs through them. Daquan Township and Jingouhe Town are greatly influenced by Shawan County. As a vegetable base in Shawan County, Wulan Wusu Town is close to Shihezi City. As a vegetable base in Shawan County, Anjihai Town has the reputation of "hometown of peppers in China", which is close to Dushanzi and Kuitun, and is mainly used in Dushanzi and Kuitun. Geographically speaking, only the ancient town of Bortong has the worst external traffic conditions.
2.2 the influence of central towns
(1) Central town is the main source of means of production, technology and information for regional agricultural production, and the focus of production organization and management. Therefore, the closeness with the center directly affects all aspects of production and the ultimate realization of agricultural land value. The influence of central towns on agricultural land mainly depends on two aspects: first, the function and grade of towns; The second is the relative distance from the central town.
In the actual operation process, some densely populated towns are not only influenced by the central town of this county, but also the agricultural land in marginal towns is greatly influenced by neighboring counties and cities. So we should consider its influence.
Generally, agricultural land at county level is classified, and the functional classification order of central position is: county level, township level and village level. From high to low, the central towns of county towns are divided into city (county) level (including this county and its neighboring counties), township level and village level. The functions of the central town include the functions of the town corresponding to the level of the center itself and the functions of its lower levels. The influence of the center on the level of agricultural land is comprehensively reflected by these functions and should be measured by the function score of the corresponding level.
(2) Determine the service radius and relative distance of the functions of urban centers at all levels. Through the distribution map of the town center, the service radius of the functions of the town center at all levels is determined by the following formula:
1) The functional service radius of municipal towns is equal to the maximum distance from the edge of municipal center to the edge of contiguous agricultural land;
2) The service radius of functions at all levels other than the functions of municipal towns is equal to the maximum service distance of towns at the same level.
The influence radius from the centers at all levels is calculated by the actual maximum action distance of the unit from the county (neighboring county) and the township center, and the formula is as follows:
Collection of Papers on Land Resources Monitoring and Investigation Project [2]
Where: Fi is the central score of the I-level center; Fi is the function of the first-level center; D is the maximum radius of action; Di is the actual distance to the class I center.
2.3 Road accessibility
Road accessibility reflects the road accessibility in the land unit, which is related to the road type and the distance from the road. According to the road system and actual function in the county, the roads in the county are divided into three levels, namely, main roads (national roads and provincial roads), secondary roads (county roads and township roads) and branch roads (village roads). Because the distribution of main roads in the county is greatly influenced by topography, the actual influence distance of roads is taken as the action radius of roads, the average traffic capacity of roads is taken as the action index of roads at all levels, and the score is calculated by linear attenuation method.
Table 1 quantitative classification table of influence degree of Shawan county central town
Table 2 Road Accessibility Function Scoring Table
The calculation adopts linear attenuation method, and the formula is:
Collection of Papers on Land Resources Monitoring and Investigation Project [2]
Where: Fi is the access function score of the first-class road; Fi is the function of Class I road; D is the maximum service radius; Di is the distance from the adjacent road.
2.4 the impact of farmers' markets
The farmer's market affects the consumption, transportation and production costs of agricultural products. In the classification of agricultural land, we should also consider the farmer's market in this county and its neighboring counties, and classify the function according to the scale. The calculation method and principle are the same as those of the central town.
2.5 Calculation of position coefficient
Whether the quantitative grading of scoring factors is reasonable is the key to ensure the accuracy and scientificity of the results; Weight is the key determinant of the comprehensive score of the unit. The weight of grading factors in Shawan county is determined by derivative Delphi method.
Table 3 Quantitative Classification and Weight Table of Location Factors in Shawan County
According to the weighted summation method, the scoring factors are synthesized into scoring factor scores, and the calculation method is as follows:
Collection of Papers on Land Resources Monitoring and Investigation Project [2]
Where: Hi is the location factor index of the I-th grading unit; I is the number of grading units; J is the number of grading factors; Wj is the weight of the j th grading factor; Fij is the score of the j th grading factor in the i th grading unit.
3 Result analysis
Table 4 Weight Table of Agricultural Land Classification Factors in Shawan County
According to the above index system and weight, it is concluded that the agricultural land in Shawan County is divided into five grades, among which I and II are distributed in the suburbs of Shawan County and the remote towns such as Wulanwusu and Anjihai, which are close to neighboring counties and cities. Ⅳ and Ⅴ grades are distributed in towns close to mountainous areas with inconvenient transportation, such as the ancient town of Boertong, which basically conforms to the present situation of agricultural land utilization in Shawan County.
Table 5 Distribution of Agricultural Land Grades in Shawan County
Considering the index of location factors to neighboring counties, the classification ratio of agricultural land in Anji Sea, Wulanwusu, Liumaowan and Sidaohezi Town has changed. Because these four towns are less influenced by Shawan county in location, but more influenced by neighboring counties.
4 Conclusion theory
On the basis of analyzing the location factors of agricultural land classification in Shawan County, this paper selects three location factors: the influence of central town, the influence of farmers' market and the accessibility of roads, and considers and quantifies the influence of neighboring counties on agricultural land location. The result accords with the actual situation of agricultural land use in Shawan County. Therefore, in the process of agricultural land classification, for counties with vast territory and dense villages and towns, it is necessary to consider the situation that peripheral towns are affected by neighboring counties.