资源科学 ›› 2019, Vol. 41 ›› Issue (4): 753-765.doi: 10.18402/resci.2019.04.12

• 土地资源 • 上一篇    下一篇

土壤肥力及其影响因素的尺度效应——以北京市平谷区为例

葛畅1, 刘慧琳1, 聂超甲1, 沈强2, 张世文1   

  1. 1. 安徽理工大学地球与环境学院,淮南 232001;
    2. 安徽理工大学测绘学院,淮南 232001
  • 收稿日期:2018-06-27 修回日期:2018-11-02 发布日期:2019-04-25
  • 通讯作者: 国家重点研发计划项目(2016YFD0300801); 国家自然科学基金项目(41471186;41571217)
  • 作者简介:葛畅,男,山东临沂人,硕士生,研究方向为土壤肥沃耕层提升潜力与信息化管理。E-mail:gechang1105@126.com

Scale effect of soil fertility spatial variability and its influencing factors

GE Chang1, LIU Huilin1, NIE ChaoJia1, SHEN Qiang2, ZHANG Shiwen1   

  1. 1. Earth and Environmental Sciences, Anhui University of Science and Technology, Huainan 232001, China;
    2. Faculty of Surveying and Mapping, Anhui University of Science and Technology, Huainan 232001, China
  • Received:2018-06-27 Revised:2018-11-02 Published:2019-04-25

摘要: 为揭示区域土壤肥力空间变异与影响因素及其随尺度变化的特征,本文以北京市平谷区为研究区,选择全区(L)、西部三镇(M)及三镇加密采样(S)三种尺度,以加权和法计算得到的土壤综合肥力指数(IFI)作为土壤肥力的表征,并结合变异函数与地理加权回归(GWR)等方法,分析IFI空间变异特征、各评价指标对土壤肥力贡献程度及其尺度效应,探究不同尺度土壤肥力影响因素作用差异。结果表明:不同尺度下土壤各指标差异明显,而三种尺度下IFI均在0.61左右,不同尺度间IFI变异度变化与其他各指标均不相同;IFI空间变异性具有明显的尺度效应,IFI块基比随着尺度的减小而增加,随机因素引起的变异在总变异中所占比重逐渐增大,L尺度表现为强空间相关性,M尺度表现为中等空间相关性,S尺度表现为弱空间相关性;不同尺度下不同土壤养分含量对IFI的贡献程度不同,L到M尺度各养分系数有所降低,M到S尺度各养分系数变化范围略有增加,单一指标对IFI的作用会受到其他指标的影响。土壤亚类、母质等因素对IFI的影响具有明显的尺度效应,随着尺度的降低各因素对IFI的影响作用总体上呈减弱的趋势。研究结果揭示了平谷区土壤肥力空间变异特征与影响因素及其随尺度的变化特征,为不同尺度下区域土壤肥力评价、空间格局分析等提供了技术支撑。

关键词: 土壤综合肥力指数, 影响因素, 尺度效应, 变异函数, 地理加权回归, 北京市平谷区

Abstract: In order to reveal the spatial variability of regional soil fertility and its influencing factors, and their change with scale, this study took Pinggu District of Beijing Municipality as the study area, and examined soil fertility and varibility at three spatial scales — the whole district (large), three towns in the western part of the district (medium), and dense sampling in the same three twons (small). The soil Integrated Fertility Index (IFI), which was calculated by the weighted sum method, was used for the characterization of soil fertility. Combined with the methods of variation function and geographically weighted regression (GWR), the spatial variability characteristics of IFI, the contribution degree of each evaluation indicator to soil fertility, and the scale effect were analyzed. Difference of the influencing factors of soil fertility at different scales were identified and characterized. The results show that the difference of soil fertility influencing factors at different spatial scales was obvious, while IFI was around 0.61 at all three scales, and the CV ratio changes of IFI between different scales were different compared to other indicators. The spatial variability of IFI illustrated a significant scale effect. The C0/Sill of IFI increased with the decrease of scale and the proportion of variation caused by random factors increased gradually. IFI showed a strong spatial correlation at the large scale, moderate spatial correlation at the medium scale, and weak spatial correlation at the small scale. The contribution of different soil nutrient contents to IFI varied at different scales. From the large to the small scale, the nutrient coefficients exhibited a decreasing trend, and the range of nutrient coefficients increased slightly from medium to small scale. The effect of a soil property on IFI will be affected by other properties. Factors such as soil subclass and parent material had an obvious scale effect on IFI. As the scale decreases, the influence of various factors on IFI decreased generally. The results provide a technical support for regional soil fertility evaluation and spatial pattern analysis at different scales.

Key words: soil Integrated Fertility Index(IFI), influencing factors, scale effect, variogram, geographically weighted regression, Pinggu District of Beijing Municipality