三调坡度图碎面融合规则探讨

Discussion on Fusion Rule of Small Area Spots for Slope Map inThe Third National Land Survey

第三次全国土地调查对坡度图碎面处理规则没有作具体的规定,只要求各省依据本省地形地貌特点自行定义最小上图面积指标,但对于坡度级就低不就高原则并入邻近图斑这一点有着不同的处理方式。文章就“就低不就高原则并入邻近图斑”这一关键点进行分析,探讨不同处理方式对耕地面积的影响趋势,以及不同处理方式对国土面积统计的影响。实验证明,坡度图碎面处理规则的细化能为今后坡度图的生产提供参考,且能更细致的反映出地貌情况。

In The Third National Land Survey,there were no specific provisions on the processing rules of small area spots for slope map.So,each province defined its own minimum area index of the top chart according to its own topographic features,but there were different processing methods for“incorporating small area spots into the adjacent map spots based on the principle of choice the low not the high into”.Therefor,this paper analyzed the principle,and discussed the influence trend of different processing methods on the cultivated land area,as well as the influence of different processing methods on the national land areastatistics.The result of experiment has shown that,the refinement of processing rules of small area spots for slope map can provide a reference for the future production of slope map,and can reflect the topographic features in details.