以甘肃省榆中县为例，建立县域耕地质量监测评价体系，运用"重点因素划定"方法划分县域耕地质量渐变类型分区并确定主导因素，布设监测样点。对样点的主导因素进行监测，获取样点等别变化情况，通过计算各监测样点代表面积，进而估算出渐变类型分区、县域耕地等别变化情况。结果表明，相比2017年耕地质量更新评价成果，榆中县耕地国家利用等级平均提高0.38等。榆中县耕地质量变化的主导因素为灌溉保证率和土壤有机质含量。干旱瘠薄型和山地干旱型分区灌溉保证率未发生变化，肥力提升型区域土壤有机质含量有降低趋势。为了提升榆中县耕地质量，对于无灌溉保证率的问题，需实施引灌工程进行解决，而土壤有机质含量较低则需通过长期持续的测土配方施肥或农家肥大量施用等手段解决。

Taking Yuzhong County in Gansu Province as an example， the monitoring and evaluation system of cultivated land quality at county level was established， using the method of “key factor delineation” to divide the county-level cultivated land quality gradual change types，determines the leading factors， and arranges monitoring points. Monitor the dominant factors of the sample points， obtain the changes of the sample points，and calculate the representative area of each monitored sample， and then estimate the change of the gradual type districts and the cultivated land of the county. The results showed that compared with the updated evaluation results of the quality of cultivated land in Yuzhong County in 2017， the national utilization of cultivated land in Yuzhong County has increased by 0.38 on average. The main factors for changes in the quality of cultivated land in Yuzhong County are the irrigation guarantee rate and the content of soil organic matter.The arid and barren type and the mountain arid type have no change in the guarantee rate of zoning irrigation， and the soil organic matter content in the fertility-enhancing area has a tendency to decrease. In order to improve the quality of cultivated land in Yuzhong County， irrigation projects should be implemented to solve the problem of no irrigation guarantee rate， while the low soil organic matter content should be solved by long-term continuous soil testing and formula fertilization or large amount of farm fertilizer application.

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甘肃省自然资源厅项目“甘肃省耕地质量等别监测评价”(甘国土利发〔2017〕17号)。