The Spatial Data Quality Control System Of The Second Rural Land Survey

The important embodiments and basal applications of the Second National Land Survey results are the four level databases which are as follows:the national, the provincial, the municipal and the county database. All of them will provide the important basal data for the daily management of land resources and decision-making, but the data quality is the key factor in applying the database results, in addition, unreliable and false data will result in wrong decisions, even cause great losses. Therefore, the accurate land survey data is the crucial foundation of the national economic construction and social development, from this it appears that taking effective measures to ensure the quality of database results, especially controlling the basal link of the four levels of database construction—the quality of county database construction, become the focus problem of us investigators.In order to ensure the quality of database results, the National Land Survey Organization organizes the related companies to develop the software of inspecting the database quality, the software unifies inspection standards and methods, and also achieves the good effects. But from the investigations of the county database construction, we find a few data production units just partially consider that so long as the data can be checked through the software published by the Country is just ok. So they cancel some items which need manual inspection, thus ignore the quality control of database construction process. In order to guarantee the accuracy and reliability of the land survey database construction, this article analyzes the problem that how to strengthen the quality in the process of land survey from the perspective of production units. Then check out the problems and then solve them at the initial data production stage, avoid the errors caused by multiple stacking and made data more complicated, prevent the data from re-doing and modifying repeatedly. Thereby it's crucial for the Second National Land Survey to put the quality control into force to ensure the data quality in a series of production process from production of remote sensing images, image interpretation, field survey, data acquisition and processing to loading the data into the database. Therefore, this article analyzes the quality problems in detail during each process, and puts forward the methods to optimize the data accuracy and reduce data errors accordingly. Through the quality control in each step of the land survey, we strive to achieve the overall quality requirement of database examination and inspection.