【摘要】 为了准确获取土壤钾素剖面分布信息,掌握区域钾素运移和合理精准施肥的需要,基于134个剖面(0—100 cm)采样数据,运用经典统计学和地统计学方法探讨了成都平原西部土壤速效钾剖面分布特征,并对比分析了成土母质、土壤类型和土地利用方式对土壤速效钾剖面分布的影响。结果表明:土壤速效钾含量在水平方向上具有一定的规律性,其高值密集在金马河以南的崇州、邛崃和大邑区域,而低值出现在都江堰—郫县—温江一带,低值区面积占研究区面积50%以上,总体呈现由西南部向东北部显著降低趋势。垂直方向上0—100 cm随土层逐渐降低,表层土壤显著高于下层土壤(P<0.05),下层土壤变幅(最大值与最小值之差)随土壤深度的增加逐渐减小。0—100 cm不同土层块金系数均为25%～75%,表现为中等程度空间自相关性,受结构性因素和随机因素共同影响。表层土壤速效钾空间分布受成土母质、土壤类型和土地利用方式共同影响,土壤类型的解释能力最高,分别是成土母质和土地利用方式的1.97,2.58倍;下层土壤主要受成土母质和土地利用方式的影响,影响程度均随着土层深度的增加而增加,相较之下,母质的影响程度增加更为显著。总体来看,成土母质和土地利用方式是影响研究区土壤速效钾剖面分布的主控因素。更多还原

【Abstract】 In order to accurately obtain the distribution information of soil potassium in the soil profile, and know well the regional migration of potassium and the need of reasonable precision fertilization, 134 soil profile(0—100 cm) samples were collected. Based on the sampling data, the distribution characteristics of soil available potassium in soil profiles of the western part of Chengdu Plain were studied through classical statistical and geostatistical methods, and the effects of parent material, soil type and land use on the available potassium distribution were compared and analyzed. The results found that the soil available potassium content had certain regularity in the horizontal direction, and its high value was concentrated in the Chongzhou, Qionglai and Dayi areas, which were south parts of the Jinma River, while the low value appeared in the Dujiangyan-Pixian-Wenjiang area. The area of the low-value-area accounted for more than 50% of the study area, and the overall showed a significant downward trend from the southwest to the northeast. In the vertical direction, the content of soil available potassium decreased with the increasing of soil depth in the range of 0 to 100 cm, and the available potassium content in top soil was significantly higher than that in the lower soil layer(P<0.05). The amplitude of soil available potassium content(the difference between the maximum and the minimum) in the lower soil gradually decreased with the increasing of soil depth. The nugget coefficients of different soil layers within 0 to 100 cm were between 25% and 75%, showing moderate spatial autocorrelation, which were affected by structural and random factors. The spatial distribution of available potassium in surface soil was affected by soil parent material, soil type and land use pattern, and the explanatory ability of soil type was the highest, which was 1.97 and 2.58 times that of soil parent material and land use pattern, respectively. The spatial distribution of available potassium in lower layer soil was mainly affected by the parent material and land use pattern, and the impact extents both increased with the increasing of soil depth, however the influence of parent material was more significant. The results showed that the parent material and land use pattern were the main controlling factors, which affecting the profile distribution of soil available potassium in the study area.更多还原