中文摘要：

以华北平原曲周18年长期定位试验的农田土壤为研究对象,利用偏光显微镜观察常规种植、无公害种植和有机种植3种种植方式下的土壤薄片,研究种植方式对土壤微形态特征的影响。结果表明：3种种植方式下的土壤和土壤粗颗粒的矿物组合基本一致,主要由石英和长石组成,但颗粒的形态和粒径有一定差别;有机种植下,土壤表层结构由中度分离的块状和板状结构为主变为团粒结构为主,发育良好的团聚体含量明显增加,土壤容重显著下降,有机质显著增加;表层土壤容重为1.19 g/cm^3,有机质含量为22.67 g/kg,总孔隙度高达32%。常规种植条件下,土壤表层结构以中度分离的块状结构为主,土壤结构较为紧实,发育程度较低;表层土壤容重为1.30 g/cm^3,有机质含量为18.42 g/kg,表层的总孔隙度为30%。无公害种植条件下,土壤表层结构以中度分离的团块状结构和少量的高度分离的粒状结构为主,土壤结构发育程度居于有机种植和常规种植二者之间。因此,有机种植条件下土壤结构疏松,土壤透气性良好,有利于作物生长。

英文摘要：

Based on an 18-year experiment with different planting patterns in Quzhou County of Huabei Plain, the farmland soils under the conventional cultivation, pollution-free cultivation and organic planting conditions were used to investigate the effects of planting patterns on soil micro morphological characteristics. Soil samples under the three planting conditions were collected and then soil thin sections were made. Soil micro morphological characteristics in soil thin sections were segmented from cross plain light photographs by image analysis. Results showed that the three soils were quite similar in mineral composition under three planting patterns. Their coarse granules were mainly formed of quartz and feldspar,but there was somewhat difference in size and shape of particles. The soil matrix and soil aggregates were well developed and soil organic matters were increased by about 25% under the organic planting condition,compared with conventional cultivation. The organic planting led to the highest soil pore area and soil surface porosity was up to 32%,the bulk density was the lowest with value of1. 19 g/cm^3 and the organic matter was the highest of 22. 67 g/kg. Under the conventional cultivation condition,the bulk density of topsoil was 1. 30 g/cm^3,the organic matter was 18. 42 g/kg,the soil surface porosity was 30%,and soil structure was tight and under-developed. Under the pollution-free cultivation condition,the development degree of soil structure was bigger than that under the conventional cultivation condition,but it was less than that under organic planting condition. Therefore,soil structure was loose and well developed under the organic cultivation condition for plant growth.