title: Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China.
abstract: Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.
authors.affiliation: State Key Laboratory of Forest Ecology and Environment, China's State Forestry Administration, The Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China. Niuxiang@caf.ac.cn.
authors.forename: Xiang
authors.initials: X
authors.lastname: Niu
authors.affiliation: College of Forestry/Mountain Tai Forest Ecosystem Research Station of State Forestry Administration/Shandong Provincial Key Laboratory of Soil Erosion and Ecological Restoration, Shandong Agricultural University, Tai'an 271018, China. gaopengy@163.com.
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Forest Ecology and Environment, China's State Forestry Administration, The Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China. wangbing@caf.ac.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.affiliation: College of Forestry/Mountain Tai Forest Ecosystem Research Station of State Forestry Administration/Shandong Provincial Key Laboratory of Soil Erosion and Ecological Restoration, Shandong Agricultural University, Tai'an 271018, China. smile123liuyu@163.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000383:Agriculture; D000538:Aluminum Silicates / Q000737:chemistry*; D002681:China; D000077215:Clay; D003247:Conservation of Natural Resources; D004463:Ecology; D065928:Forests; D017709:Fractals; D065948:Grassland; D031324:Juglans / Q000254:growth & development; D010316:Particle Size; D028223:Pinus / Q000254:growth & development; D027927:Pistacia / Q000254:growth & development; D006109:Poaceae / Q000254:growth & development; D029963:Quercus / Q000254:growth & development; D031301:Robinia / Q000254:growth & development; D012987:Soil / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D012987:Soil; D000077215:Clay
keywords: Return Farmland to Forests Project; fractal method; monofractal and multifractal dimension; soil particle