陕西省农田土壤紧实度空间变异及其影响因素

为探明陕西省农田土壤紧实度现状及区域差异,2013年在全省选取228个调查点,对1 100多块地的农田土壤紧实度进行调查。结果表明:陕西省农田耕层土壤紧实度为250.0~2 080.0kPa,平均为781.3kPa,变异性中等;全省各区犁底层紧实度为716.0~5 650.0kPa,平均为2 900.5kPa,中等变异。耕层土壤紧实度以关中东部和陕南东部较大,1 000kPa以上,陕北大部分县区耕层比较疏松;犁底层紧实度以关中地区及陕南东部较大,在3 000kPa以上,陕北地区犁底层紧实度普遍较低。耕层土壤紧实度主要受区域位置、农田利用类型、地形、作物类型、耕作方式及土壤类型影响(P0.05);犁底层紧实度受区域位置、作物类型、地形、耕作方式、熟制、机耕年限、灌溉情况、土壤类型以及土壤含水量等因素影响(P0.05)。

Spatial Variability and Influence Factors of Cropland Soil Compaction in Shaanxi Province

In order to explore the current condition of cropland soil compaction in different regions in Shaanxi province,a soil compaction survey was conducted in 1 100 patches in 228 points throughout the whole province in 2013.The results showed that the average compaction of plow P layer in cropland in Shaanxi province was 781.3 kPa,ranging from 250.0 kPa to 2 080.0 kPa with a moderate variability; the average compaction of plow pan was 290.5 kPa,ranging from 716.0 kPa to 5 650.0 kPa with a moderate variability.The plow P layer compaction of eastern Guanzhong area and eastern Shannan area was larger compared with other regions,with a value more than 1 000 kPa.Most part of northern Shaanxi area had a relatively looser plow player.Plow pan compaction in Guanzhong area and eastern Shannan area were comparatively larger with a value of 3 000 kPa or more. Plow pan compaction of northern Shaanxi area was generally lower.Plow player compaction was influenced mainly by regional location,plots situation,terrain,crop types,tillage methods and soil types (P<0.05);and plow pan compaction was influenced by regional location,crop types,topography,tillage methods,cropping system,mechanical tillage years,irrigation conditions,soil types and soil moisture (P<0.05).