Study On The Associated Types Of The Factors Of Arable Land Gradation

Agricultural land rate and appraisal is a new land discipline. That is suitable for the need of socialist rural land use system reform. At present, it is a urgent task for land management departments. It is base on the Marxism rent theory, land price theory, land location theory, land reward conversion theory and ecology theory.This research elaborated the meaning and features of associated land types. Based on this, the system of associated land types was founded. According to the CRT rule and the concrete situations of ZhuoLu County, the grading standards included seven main factors (slope, soil body thickness, condition of irrigation, O.M., soil texture, salt-status, soil body configuration). According to the conditions of ZhuoLu County, it was divided three index-control regions: plain region, hilly-land region and mountainous region. On the base of this, sixty-five associated land types of ZhuoLu County were founded, the natural quality fraction of them were worked out and were made out in index table. The merit and defect of the natural yield separation method and quality embody point method were analyzed and the method of potential comparable yield was put forward. The feasibility of associated land types was tested by this method. The method of associated land types was a simple and easy method that provided a quick and accurate model of grading and could be used in other cities or counties. Based on the study on ZhuoLu County, the grading results objectively and accurately reflected the practical condition of this county and confirmed the science and feasibility of the associated land type method.