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小比例尺土壤图制图单元内土体构型往往不一致,以土壤图为评价单元,土体构型往往难以作为一个评价指标。本文以河南省为例,基于1∶5万比例尺土壤图,根据县域土种志记载的典型剖面信息,将全省428个土种按照质地构型和障碍土层归纳为32种土体构型,然后在GIS中概括生成1∶50万土体构型图,并分析了该图与1∶50万河南省土壤图在空间表达方面的差异以及土体构型指标对耕地地力评价结果的影响。结果表明:土体构型图图斑多样性低,面积变异系数大,但图斑平均密度大,图斑形状指数复杂,既实现对生产性能变异较低区域的图斑简化,又保持生产性能变异较大区域图斑表达的高精度;在统一的评价体系下,若土体构型参与耕地评价,1∶50万土壤图的评价结果与土体构型图的评价结果在省级尺度上趋势相似,但后者与市级、县级耕地地力评价相比产生的尺度效应较低,与小麦单位产量拟合度更高;若采取剔除土体构型指标的技术路线,评价精度较前两者均明显降低。
Soil profiles in small-scale soil mapping units tend to be inconsistent. Taking soil maps as evaluation units, the soil configuration is often difficult to be used as an evaluation index. Taking Henan Province as an example, based on the 1: 50000 scale soil map, based on the typical profile records of the soil species records in the county, 428 soil types in the province were classified into 32 soil types , And then 1: 500,000 soil structure maps are summarized in GIS, and the differences between this map and 1: 500,000 soil maps in Henan Province are analyzed and the effect of soil structure indexes on the assessment results of cultivated land productivity is analyzed . The results showed that the maps of soil texture map were low in diversity but large in coefficient of variation of area, but the average density of patches was large, and the shape index of patches was complicated, which not only reduced the patch size but also maintained the production performance in areas with lower variability of production performance In the unified evaluation system, if the soil structure is involved in the evaluation of arable land, the evaluation results of the 1: 500000 soil map and the soil structure map are evaluated on the provincial scale The trend is similar, but the latter has lower scale effect compared with the evaluation of farmland productivity at city and county level, and the fitting degree with unit output of wheat is higher. If the technical route of removal of soil configuration index is adopted, the evaluation accuracy is higher Both are significantly lower.