Chin J Plan Ecolo ›› 2007, Vol. 31 ›› Issue (1): 56-65.doi: 10.17521/cjpe.2007.0008

• Research Articles • Previous Articles     Next Articles

STUDY ON FRACTAL FEATURES OF SOIL AGGREGATE STRUCTURE UNDER NATURAL EVERGREEN BR OADLEAVED FOREST AND ARTIFICIAL REGENERATION IN SOUTHERN SICHUAN PROVINCE

GONG Wei; HU Ting_Xing; WANG Jing_Yan; GONG Yuan_Bo; RAN Hua; ZHANG Shi_ Rong; LIAO Er_Hua   

  1. Sichuan Provincial Key Laboratory of Ecological Forestry Engineering, Sichuan Agricultural University, Ya’an, Sichuan 625014, China
  • Online:2007-01-30 Published:2007-01-30
  • Contact: GONG Wei

Abstract:

Aims Fractal theory, a study tool popular in recent years, offers a new means to quantitatively investigate soil structure. Soil structure is the basis of soil fertility, which is the basic property of soil. It can be comprehensively reflected by soil physical, chemical and organism properties, and change of soil structure will result in changes in other soil properties. Fractal features of soil aggregate structure under natural evergreen broadleaved forest and regeneration of artificial systems is rarely studied. We chose to study natural evergreen broadleaved forest and three artificial plantations of Sassafras tzumu, Cryptomeria fortunei andMetasequoia glyptostroboidesin southern Sichuan Province. Our objective was to determine a) effects of artificial regeneration on fractal features of soil aggregate structure, b) effects of different plantations on fractal dimension of soil aggregate structure, c) relationships between fractal dimension and soil physical properties, nutrient content and microbe number, and d) use of fractal dimension of soil aggregate structure for evaluating the water conservation, fertility and microbe activity of soil. 
Methods Soils were collected from each forest to determine a) fractal dimension of soil aggregate structure using Yang Peiling’s approach and b) soil physical and chemical properties and soil microbe number. The relationship between fractal dimension and soil physical properties, nutrient content and microbe number was analyzed with regression analysis.
Important findings Natural evergreen broadleaved forest and artificial regeneration resulted in increased fractal dimension of soil aggregate structure and percent of construction damage, poorer soil physical properties and reduced nutrient content and number of microbes. The higher the content of aggregates, water-stable aggregates and water-stable big aggregates in soil, the smaller the fractal dimension of soil aggregate structure. With wet sieving condition and decreased fractal dimension, the percent of construction damage decreased. There were close relationships between fractal dimension of soil aggregate structure and soil natural water content, bulk density, capillary porosity, non-capillary porosity, original infiltration coefficient, stable infiltration coefficient, content of organic matter, total-N, hydrolysis-N, total-P, available-P, total-K, available-K and the number of bacteria, fungi and actinomyces. Different stands had different effects for maintenance of soil structure, which resulted in changes of soil physical, chemical and organism properties under natural evergreen broadleaved forest and artificial regeneration, and changes of soil aggregate structure had an effect on the value of fractal dimension. This indicates that fractal dimension can be used as a comprehensive quantitative index to evaluate water conservation function, fertility states and microbe activity of soil for natural evergreen broadleaved forest and artificial regeneration. It provides a solid foundation for protecting natural evergreen broadleaved forest, choosing appropriate trees for its artificial regeneration, managing soil after artificial regeneration and choosing trees for converting farmland to forest.

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[1] . [J]. Chin Bull Bot, 1994, 11(专辑): 19 .
[2] Xiao Xiao and Cheng Zhen-qi. Chloroplast 4.5 S ribosomol DNA. II Gene and Origin[J]. Chin Bull Bot, 1985, 3(06): 7 -9 .
[3] CAO Cui-LingLI Sheng-Xiu. Effect of Nitrogen Level on the Photosynthetic Rate, NR Activity and the Contents of Nucleic Acid of Wheat Leaf in the Stage of Reproduction[J]. Chin Bull Bot, 2003, 20(03): 319 -324 .
[4] SONG Li-Ying TAN Zheng GAO Feng DENG Shu-Yan. Advances in in vitro Culture of Cucurbitaceae in China[J]. Chin Bull Bot, 2004, 21(03): 360 -366 .
[5] . [J]. Chin Bull Bot, 1994, 11(专辑): 76 .
[6] LI Jun-De YANG Jian WANG Yu-Fei. Aquatic Plants in the Miocene Shanwang Flora[J]. Chin Bull Bot, 2000, 17(专辑): 261 .
[7] XU Jing-Xian WANG Yu-Fei YANG Jian PU Guang-Rong ZHANG Cui-Fen. Advances in the Research of Tertiary Flora and Climate in Yunnan[J]. Chin Bull Bot, 2000, 17(专辑): 84 -94 .
[8] Sun Zhen-xiao Xia Guang-min Chen Hui-min. Karyotype Analysis of Psathyrostachys juncea[J]. Chin Bull Bot, 1995, 12(01): 56 .
[9] . [J]. Chin Bull Bot, 1994, 11(专辑): 8 -9 .
[10] Yunpu Zheng;Jiancheng Zhao * ;Bingchang Zhang;Lin Li;Yuanming Zhang . Advances on Ecological Studies of Algae and Mosses in Biological Soil Crust[J]. Chin Bull Bot, 2009, 44(03): 371 -378 .