Soil phosphorus tests I: What soil phosphorus pools and processes do they measure?

被引:36
作者
Moody, Philip W. [1 ]
Speirs, Simon D. [2 ,3 ]
Scott, Brendan J. [4 ,5 ]
Mason, Sean D. [6 ]
机构
[1] DSITIA, Dutton Pk, Qld 4102, Australia
[2] NSW Dept Primary Ind, Graham Ctr Agr Innovat, Narellan, NSW 2567, Australia
[3] Charles Sturt Univ, Narellan, NSW 2567, Australia
[4] NSW Dept Primary Ind, Graham Ctr Agr Innovat, Wagga Wagga, NSW 2650, Australia
[5] Charles Sturt Univ, Wagga Wagga, NSW 2650, Australia
[6] Univ Adelaide, Sch Agr Food & Wine, Glen Osmond, SA 5064, Australia
关键词
P buffer capacity; P diffusion; YIELD RESPONSE; WHEAT;
D O I
10.1071/CP13112
中图分类号
S [农业科学];
学科分类号
09 ;
摘要
The phosphorus (P) status of 535 surface soils from all states of Australia was assessed using the following soil P tests: Colwell-P (0.5 M NaHCO3), Olsen-P (0.5 M NaHCO3), BSES-P (0.005 M H2SO4), and Mehlich 3-P (0.2 M CH3COOH + 0.25 MNH4NO3 + 0.015 MNH4F + 0.013 MHNO3 + 0.001 M EDTA). Results were correlated with soil P assays selected to estimate the following: soil solution P concentration (i.e. 0.01 M CaCl2 extractable P; Colwell-P/P buffer index); rate of P supply to the soil solution (i.e. P released to FeO-impregnated filter paper); sorbed P (i.e. Colwell-P); mineral P (i.e. fertiliser reaction products and/or soil P minerals estimated as BSES-P minus Colwell-P); the diffusive supply of P (i.e. P diffusing through a thin gel film, DGT-P); and P buffer capacity (i.e. single-point P buffer index corrected for Colwell-P, PBICol). Across all soils, Colwell-P and BSES-P were highly correlated with FeO-P (r = 0.76 and 0.58, respectively). Colwell-P was moderately correlated with mineral P (r = 0.24), but not solution P. Olsen-P and Mehlich-P were both highly correlated with FeO-P (r = 0.80 and 0.78, respectively) but, in contrast to Colwell-P and BSES-P, also showed moderate correlations with soil solution P (r = 0.29 and 0.34, respectively) and diffusive P supply (r = 0.31 and 0.49, respectively). Correlation coefficients with mineral P were r = 0.29 for Olsen-P and r = 0.17 for Mehlich-P. Soils were categorised according to their pH, clay activity ratio, content of mineral P and CaCO3 content, and the relationships between the empirical soil P tests examined for each soil category. Olsen-P and Colwell-P were correlated across all soil categories (r range 0.66-0.90), and a widely applicable linear equation was obtained for converting one soil test to the other. However, the correlations between other soil tests varied markedly between soil categories and it was not possible to develop such widely applicable conversion equations. Multiple step-up linear regressions were used to identify the key soil properties affecting soil solution P, P buffer capacity, and diffusive P supply, respectively. For all soil categories, solution P concentration (measured by CaCl2-P) increased as rate of P supply (measured as FeO-P) increased and P buffer capacity decreased. As an assay of sorbed P, Colwell-P alone did not significantly (P > 0.05) explain any of the variability in soil solution P, but when used in the index (Colwell-P/P buffer index), it was highly correlated (r = 0.74) with CaCl2-P. Soil P buffer capacity was dependent on different properties in different soil categories, with 45-65% of the variation in PBI accounted for by various combinations of Mehlich-Al, Mehlich-Fe, total organic C, clay content, clay activity ratio, and CaCO3 content, depending on soil category. The diffusive supply of P was primarily determined by rate of P supply (measured as FeO-P; r range 0.34-0.49), with significant (P < 0.05) small improvements due to the inclusion of PBICol and/or clay content, depending on soil category. For these surface soil samples, key properties of pH, clay activity ratio, clay content, and P buffer capacity varied so widely within individual Australian Soil Orders that soil classification was not useful for inferring intrinsic surface soil P properties such as P buffer capacity or the relationships between soil P tests.
引用
收藏
页码:461 / 468
页数:8
相关论文
共 25 条
[1]   Towards a single-point method for measuring phosphate sorption by soils [J].
Barrow, NJ .
AUSTRALIAN JOURNAL OF SOIL RESEARCH, 2000, 38 (06) :1099-1113
[2]   A MECHANISTIC MODEL FOR DESCRIBING THE SORPTION AND DESORPTION OF PHOSPHATE BY SOIL [J].
BARROW, NJ .
JOURNAL OF SOIL SCIENCE, 1983, 34 (04) :733-750
[3]   Chemical characteristics of phosphorus in alkaline soils from southern Australia [J].
Bertrand, I ;
Holloway, RE ;
Armstrong, RD ;
McLaughlin, MJ .
AUSTRALIAN JOURNAL OF SOIL RESEARCH, 2003, 41 (01) :61-76
[4]   Prediction of the CEC to clay ratio using mid-infrared spectroscopy [J].
Bloesch, Philip M. .
SOIL RESEARCH, 2012, 50 (01) :1-6
[5]  
COLWELL J. D., 1963, AUSTRALIAN JOUR EXPTL AGRIC AND ANIMAL HUSB, V3, P190, DOI 10.1071/EA9630190
[6]   A conceptual framework for improving the P efficiency of organic farming without inputs of soluble P fertiliser [J].
Conyers, M. K. ;
Moody, P. W. .
CROP & PASTURE SCIENCE, 2009, 60 (02) :100-104
[7]   EVALUATION OF PARAMETERS OF SOIL-PHOSPHORUS AVAILABILITY FACTORS IN PREDICTING YIELD RESPONSE AND PHOSPHORUS UPTAKE [J].
DALAL, RC ;
HALLSWORTH, EG .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1976, 40 (04) :541-546
[8]  
Eldridge S., 2003, Sugar soils: A guide to characterising Australian sugarcane soils
[9]   AN EVALUATION OF 8 SOIL PHOSPHATE EXTRACTANTS ON ACIDIC WHEAT-GROWING SOILS [J].
HOLFORD, ICR ;
CULLIS, BR .
AUSTRALIAN JOURNAL OF SOIL RESEARCH, 1985, 23 (04) :647-653
[10]   EFFECTS OF PHOSPHATE BUFFER CAPACITY ON YIELD RESPONSE CURVATURE AND FERTILIZER REQUIREMENTS OF WHEAT IN RELATION TO SOIL PHOSPHATE TESTS [J].
HOLFORD, ICR ;
CULLIS, BR .
AUSTRALIAN JOURNAL OF SOIL RESEARCH, 1985, 23 (03) :417-427