Abstract:
To explore the fractal characteristics of soil particle size under different management modes of reclaimed poplar forest in homestead, and provide a theoretical basis for scientific guidance of soil remediation of construction land, an experimental area was established in the abandoned rural homestead of Weicheng District, Xianyang City, Shaanxi Province. There were 4 treatments: check (no disturbance), irrigation, fertilization irrigation and natural growth. The fractal characteristics of soil particle size distribution under different management modes were examined by soil mechanical composition through collecting soil samples from four test areas. The mean contents of soil clay, silt and sand in different management modes were 14.58%, 81.21% and 4.22% in check, 14.08%, 79.92% and 5.99% in natural growth, 15.17%, 81.19% and 3.64% in irrigation, and 16.75%, 80.20% and 3.05% in fertilizer irrigation, respectively. The soil volume fractal dimension
D was in the range of 2.721 - 2.808. It was significantly positively correlated with clay content and multifractal dimension parameters (
D0 −
D10,
D−10 −
D0) (
P < 0.05), and significantly negatively correlated with sand content
(P < 0.05). The soil roughness decreased gradually in the order of irrigation, fertilization irrigation, natural growth and check experiment. The soil texture uniformity decreased gradually in the order of fertilization irrigation, irrigation, natural growth and check experiment. And the overall fractal structure of soil was gradually simplified in the order of check experiment, irrigation, natural growth and fertilization irrigation. Therefore, it could be considered that irrigation and fertilizer irrigation modes could improve the soil texture by the homestead was reclaimed into the poplar forest land. Soil volume fractal dimension D could be used as an indicator to measure soil quality change.