Field-scale variability of soil test phosphorus and other nutrients in grasslands under long-term agricultural managements

Field-scale variation of soil nutrients in grassland is becoming important because of the use of soil-nutrient information as a basis for policies such as the recently introduced EU Nitrates Directive. This study investigates the field-scale variability of soil-test phosphorus (STP) and other nutrients in two grasslands with a long-term history of poultry litter application. Two fields (field 1 for silage and field 2 for grazing pasture) were selected, and soil samples were collected based on 12 m by 12 m (field 1) and 15 m by 15 m (field 2) grids. Data were analysed using conventional statistics, geostatistics, and a geographic information system (GIS). In field 1, STP values ranged from 12.4 to 90 mg L–1 (average 38.5 mg L–1). In field 2, STP values ranged from 4.3 to 130.0 mg L–1 (average 21.4 mg L–1). Attention should be paid to long-term poultry application, as the average STP values in both fields were much greater than the recommended agronomic optimum STP status in Ireland of 8 mg L–1. Coefficient of variation values of soil nutrients in field 2 were much higher than those in field 1. Log-transformation and Box–Cox transformation were applied to achieve normality. Statistically significant (P < 0.01), positive correlations between P and other nutrients were found in both fields. Exponential and spherical models were fitted to the experimental variograms of STP in fields 1 and 2, respectively. Compared with the counterparts in field 1, soil nutrients in field 2 had larger ‘nugget-to-sill’ values, revealing that sheep grazing could weaken the spatial auto-correlation of soil nutrients. A grid of 60 m by 60 m was recommended for soil sampling in grassland, based on this study. High STP concentrations in field 1 were in the north-eastern side, which was related to uneven poultry litter application. Strong spatial similarity of low STP, magnesium, and pH values in their spatial distribution were found in field 2, confirming their strong statistical correlation.

[1]  D. Styles,et al.  Linking soil phosphorus to water quality in the Mask catchment of western Ireland through the analysis of moist soil samples , 2006 .

[2]  Margaret A. Oliver,et al.  Variograms of Ancillary Data to Aid Sampling for Soil Surveys , 2003, Precision Agriculture.

[3]  A. Gallardo,et al.  Spatial variability of soil elements in two plant communities of NW Spain , 2007 .

[4]  Andrew N. Sharpley,et al.  Practical and Innovative Measures for the Control of Agricultural Phosphorus Losses to Water: An Overview , 2000 .

[5]  Noel A Cressie,et al.  Statistics for Spatial Data. , 1992 .

[6]  A. Gassner.  Factors controlling the spatial specification of phosphorus in agricultural soils , 2003 .

[7]  P. Withers,et al.  Phosphorus transfer in runoff following application of fertilizer, manure, and sewage sludge. , 2001, Journal of environmental quality.

[8]  G. McCarty,et al.  SPATIAL VARIABILITY OF SOIL PHOSPHOROUS LEVELS BEFORE AND AFTER POULTRY LITTER APPLICATION , 2006 .

[9]  Chaosheng Zhang,et al.  Using GIS and Geostatistics to Optimize Soil Phosphorus and Magnesium Sampling in Temperate Grassland , 2013 .

[10]  William V. Harper,et al.  Practical geostatistics 2000 , 2000 .

[11]  D. Mcgrath,et al.  Spatial distribution of soil organic carbon concentrations in grassland of Ireland , 2003 .

[12]  J. Syers,et al.  Effects of season and fertiliser rate on phosphorus concentrations in pasture and sheep faeces in hill country , 1988 .

[13]  A. Konopka,et al.  FIELD-SCALE VARIABILITY OF SOIL PROPERTIES IN CENTRAL IOWA SOILS , 1994 .

[14]  Bruce S. Thorrold,et al.  A Review of New Zealand Research Measuring Phosphorus in Runoff from Pasture , 2000 .

[15]  Timothy C. Coburn,et al.  Geostatistics for Natural Resources Evaluation , 2000, Technometrics.

[16]  Chaosheng Zhang,et al.  Spatial variation of soil test phosphorus in a long-term grazed experimental grassland field , 2010 .

[17]  M. Peech,et al.  RAPID MICROCHEMICAL SOIL TESTS , 1944 .

[18]  A. Mauromoustakos,et al.  Soil phosphorus variability in pastures: implications for sampling and environmental management strategies. , 2001, Journal of environmental quality.

[19]  Hans-Georg Frede,et al.  Agricultural nitrogen, phosphorus and potassium balances in Germany : Methodology and trends 1970 to 1995 , 1998 .

[20]  F. van der Pol,et al.  Soil Mining: An Unseen Contributor to Farm Income in Southern Mali , 1994 .

[21]  Dwayne R. Edwards,et al.  Relating Extractable Soil Phosphorus to Phosphorus Losses in Runoff , 1996 .

[22]  David J. Wittry,et al.  Soil phosphorus, management practices, and their relationship to phosphorus delivery in the Iowa Clear Lake agricultural watershed. , 2003, Journal of environmental quality.

[23]  S. J. Smith,et al.  Nitrogen and Phosphorus Fate from Long-Term Poultry Litter Applications to Oklahoma Soils , 1993 .

[24]  Andrew N. Sharpley,et al.  Phosphorus management at the watershed scale:a modification of the phosphorus index , 2000 .

[25]  W. Wiebold,et al.  Different Techniques to Identify Management Zones Impact Nitrogen and Phosphorus Sampling Variability , 2003 .

[26]  Nelson,et al.  Soil Fertility and Fertilizers: An Introduction to Nutrient Management , 1998 .

[27]  T. Sauer,et al.  Spatial Variation of Plant-Available Phosphorus in Pastures with Contrasting Management , 2003 .

[28]  H. Tunney.  A Note on a Balance Sheet Approach to Estimating the Phosphorus Fertiliser Needs of Agriculture , 1990 .

[29]  Francisco Cabrera,et al.  Spatial variability of the chemical characteristics of a trace-element-contaminated soil before and after remediation , 2006 .

[30]  D. Cox,et al.  An Analysis of Transformations , 1964 .

[31]  E. O. McLean,et al.  Buffer Methods for Determining Lime Requirement of Soils With Appreciable Amounts of Extractable Aluminum , 1961 .

[32]  M. G. Cline,et al.  PRINCIPLES OF SOIL SAMPLING , 1944 .

[33]  Chaosheng Zhang,et al.  Using Moran's I and geostatistics to identify spatial patterns of soil nutrients in two different long-term phosphorus-application plots , 2011 .

[34]  J. S. Bailey,et al.  Within and between-field spatial variation in soil phosphorus in permanent grassland , 2009, Precision Agriculture.

[35]  R. Reese.  Geostatistics for Environmental Scientists , 2001 .

[36]  Chaosheng Zhang,et al.  Geostatistical analyses and hazard assessment on soil lead in Silvermines area, Ireland. , 2004, Environmental pollution.

[37]  C. W. Wood,et al.  Impact of long-term land application of broiler litter on environmentally related soil properties , 1994 .

[38]  H. Wheater,et al.  Evaluation of two hybrid metric-conceptual models for simulating phosphorus transfer from agricultural land in the river enborne, a lowland UK catchment , 2005 .

[39]  G. Kiely,et al.  Patterns and processes of phosphorus transfer from Irish grassland soils to rivers—integration of laboratory and catchment studies , 2005 .

[40]  John Doe,et al.  Soil Map of the World , 1962 .

[41]  T. C. Daniel,et al.  Determining environmentally sound soil phosphorus levels , 1996 .

[42]  A. Utset,et al.  A geostatistical method for soil salinity sample site spacing , 1998 .

[43]  Noel A Cressie,et al.  Statistics for Spatial Data, Revised Edition. , 1994 .

[44]  S. W. Melsted,et al.  Field Sampling for Soil Testing , 2015 .

[45]  R. W. Whitney,et al.  Microvariability in Soil Test, Plant Nutrient, and Yield Parameters in Bermudagrass , 1998 .

[46]  H. Tunney,et al.  Phosphorus needs of grassland soils and loss to water. , 2002 .

[47]  Olle Selinus,et al.  Statistical analyses for heavy metal contents in till and root samples in an area of southeastern Sweden , 1998 .

[48]  J. Bailey,et al.  Sampling Strategies for Mapping Soil Phosphorus and Soil Potassium Distributions in Cool Temperate Grassland , 2000, Precision Agriculture.

[49]  I. Steen,et al.  Phosphorus availability in the 21st century : Management of a non-renewable resource , 1998 .

[50]  David B. Marx,et al.  Spatial Variability of Soil Chemical Properties in Grazed Pastures , 1989 .