The effect of soil water content and microbial activity on restoring the structure of a Vertisol

被引:2
作者
Kostopoulou, SK [1 ]
Zotos, A [1 ]
机构
[1] Aristotle Univ Thessaloniki, Dept Agr, Lab Soil Sci, Thessaloniki 54124, Greece
关键词
water potential; sterilization; aggregate size distribution; aggregate stability;
D O I
10.1016/j.still.2004.07.013
中图分类号
S15 [土壤学];
学科分类号
0903 ; 090301 ;
摘要
Soils with high clay content are susceptible to structural damage, if they are intensively cultivated. The structure of soils of the Vertisol group has the tendency to restore as a result of wetting and drying. Samples of a remoulded clayey soil were exposed to seven successive wetting/drying (w/d) cycles, in order to study the change of some structural features of the newly formed aggregates. To assess the effect of soil water content and microbial activity, two different matric water potential ranges were used under sterile and non-sterile conditions. Aggregate size distribution depended on both the water potential range and microbial activity and approached to a steady state with increasing cycle number. The water stability of the 2-1 mm aggregates was affected by the activity of soil microorganisms under wet conditions and by forces of mechanical nature when the soil was reaching dryness. All cases resulted in aggregates of reduced water stability with respect to the natural aggregates. The < 50 mu m aggregated particles initially preserved stability, but after a number of w/d cycles they collapsed at a rate, depending mainly on the water potential range. (c) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:203 / 209
页数:7
相关论文
共 19 条
[1]  
ALLISON LE, 1967, METHODS SOIL ANAL 2, P1367
[2]  
ANGERS DA, 1993, SOIL SAMPLING METHOD, V61, P651
[3]  
[Anonymous], 1954, HDB USDA, V60
[4]  
[Anonymous], USDA SCS AGR HDB
[5]   THIXOTROPIC CHANGES WITH AGING OF SYNTHETIC SOIL AGGREGATES [J].
BLAKE, GR ;
GILMAN, RD .
SOIL SCIENCE SOCIETY OF AMERICA PROCEEDINGS, 1970, 34 (04) :561-&
[6]   SLAKING CHARACTERISTICS OF SOME AUSTRALIAN AND BRITISH SOILS [J].
CHAN, KY ;
MULLINS, CE .
EUROPEAN JOURNAL OF SOIL SCIENCE, 1994, 45 (03) :273-283
[7]   SOIL PHYSICAL-PROPERTIES RELATED TO SOIL-STRUCTURE [J].
HORN, R ;
TAUBNER, H ;
WUTTKE, M ;
BAUMGARTL, T .
SOIL & TILLAGE RESEARCH, 1994, 30 (2-4) :187-216
[8]   CHANGES OF STRUCTURE AND TILTH MELLOWING IN A VERTISOL DUE TO WET/DRY CYCLES IN THE LIQUID AND VAPOR-PHASES [J].
HUSSEIN, J ;
ADEY, MA .
EUROPEAN JOURNAL OF SOIL SCIENCE, 1995, 46 (03) :357-368
[9]   INFLUENCE OF AGGREGATE DIAMETER, SURFACE-AREA AND ANTECEDENT WATER-CONTENT ON THE DISPERSIBILITY OF CLAY [J].
KAY, BD ;
DEXTER, AR .
CANADIAN JOURNAL OF SOIL SCIENCE, 1990, 70 (04) :655-671
[10]  
Lynch J. M., 1985, Advances in Soil Science, USA, V2, P133