Stratified Soil Sampling Improves Predictions of P Concentration in Surface Runoff and Tile Discharge

Phosphorus (P) stratification in agricultural soils has been proposed to increase the risk of P loss to surface waters. Stratified soil sampling that assesses soil test P (STP) in a shallow soil horizon may improve predictions of P concentrations in surface and subsurface discharge compared to single depth agronomic soil sampling. However, the utility of stratified sampling efforts for enhancing understanding of environmental P losses remains uncertain. In this study, we examined the potential benefit of integrating stratified sampling into existing agronomic soil testing efforts for predicting P concentrations in discharge from 39 crop fields in NW Ohio, USA. Edge-of-field (EoF) dissolved reactive P (DRP) and total P (TP) flow-weighted mean concentrations in surface runoff and tile drainage were positively related to soil test P (STP) measured in both the agronomic sampling depth (0–20 cm) and shallow sampling depth (0–5 cm). Tile and surface DRP and TP were more closely related to shallow depth STP than agronomic STP, as indicated by regression models with greater coefficients of determination (R2) and lesser root-mean square errors (RMSE). A multiple regression model including the agronomic STP and P stratification ratio (Pstrat) provided the best model fit for DRP in surface runoff and tile drainage and TP in tile drainage. Additionally, STP often varied significantly between soil sampling events at individual sites and these differences were only partially explained by management practices, highlighting the challenge of assessing STP at the field scale. Overall, the linkages between shallow STP and P transport persisted over time across agricultural fields and incorporating stratified soil sampling approaches showed potential for improving predictions of P concentrations in surface runoff and tile drainage.

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Indicator of risk of water contamination by phosphorus from Canadian agricultural land

Water Science & Technology ◽

10.2166/wst.2006.064 ◽

2006 ◽

Vol 53 (2) ◽

pp. 303-310 ◽

Cited By ~ 14

Author(s):

E. van Bochove ◽

G. Thériault ◽

F. Dechmi ◽

A.N. Rousseau ◽

R. Quilbé ◽

...

Keyword(s):

Water Contamination ◽

Crop Residue ◽

Management Practices ◽

Agricultural Land ◽

Soil Phosphorus ◽

Soil Test ◽

Soil P ◽

Soil Test P ◽

P Balance ◽

Balance Factor

The indicator of risk of water contamination by phosphorus (IROWC_P) is designed to estimate where the risk of water P contamination by agriculture is high, and how this risk is changing over time based on the five-year period of data Census frequency. Firstly developed for the province of Quebec (2000), this paper presents an improved version of IROWC_P (intended to be released in 2008), which will be extended to all watersheds and Soil Landscape of Canada (SLC) polygons (scale 1:1, 000, 000) with more than 5% of agriculture. There are three objectives: (i) create a soil phosphorus saturation database for dominant and subdominant soil series of SLC polygons – the soil P saturation values are estimated by the ratio of soil test P to soil P sorption capacity; (ii) calculate an annual P balance considering crop residue P, manure P, and inorganic fertilizer P – agricultural and manure management practices will also be considered; and (iii) develop a transport-hydrology component including P transport estimation by runoff mechanisms (water balance factor, topographic index) and soil erosion, and the area connectivity to water (artificial drainage, soil macropores, and surface water bodies).

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Phosphorus in runoff from two highly weathered soils of the tropics

Canadian Journal of Soil Science ◽

10.4141/cjss10064 ◽

2011 ◽

Vol 91 (2) ◽

pp. 267-277 ◽

Cited By ~ 3

Author(s):

John Ramírez-Ávila ◽

David Sotomayor-Ramírez ◽

Gustavo Martínez-Rodríguez ◽

Luís Pérez-Alegría

Keyword(s):

Surface Runoff ◽

Soil Test ◽

Antecedent Soil Moisture ◽

Broiler Litter ◽

Amended Soils ◽

Weathered Soils ◽

Soil Test P ◽

Highly Weathered Soils ◽

The Tropics ◽

Bray 1

Ramírez-Ávila, J. R., Sotomayor-Ramírez, D., Martínez-Rodríguez, G. A. and Pérez-Alegría, L. R. 2011. Phosphorus in runoff from two highly weathered soils of the tropics. Can. J. Soil Sci. 91: 267–277. Agricultural fields with high soil phosphorus (P) content are important contributors to surface water degradation. Two consecutive simulated rainfall events were conducted on two Ultisols previously amended with inorganic P fertilizer or broiler litter. Soil test P (Bray 1 and Olsen) levels evaluated ranged from 1 to 350 mg kg−1. Surface runoff concentrations of total P (TP) and dissolved P (DP) generated by a 30-min runoff event were quantified. Runoff DP concentrations ranged from 0.08 to 3.98 mg L−1 in fertilizer P-amended soils and from 0.08 to 4.93 mg L−1 in broiler litter-amended soils. A single exponential model adequately described the relationships between soil test P and DP concentrations in runoff. For each soil, the soil test P-DP concentration relationships were positively influenced by soil organic matter and negatively influenced by antecedent soil moisture (P<0.05). For both soils, the soil test P-DP concentration relationships were positively influenced by groundcover percentage and negatively influenced by slope. Environmental soil test P critical levels corresponding to a runoff threshold of 1 mg L−1 DP, ranged between 176 and 296 mg kg−1 (Olsen) and 143 to 276 mg kg−1 (Bray 1) in soils amended with fertilizer-P. In broiler litter-amended soils, threshold values were 88 and 111 mg kg−1 using Olsen and Bray 1, respectively. Differences in surface runoff-P concentrations due to amendment sources, antecedent soil moisture content, soil organic matter, groundcover and slope suggest that these factors need to be considered in P management decisions at the farm level.

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Integrated Soil, Crop and Water Management System to Abate Herbicide and Nitrate Contamination of the Great Lakes

Water Science & Technology ◽

10.2166/wst.1993.0453 ◽

1993 ◽

Vol 28 (3-5) ◽

pp. 497-507 ◽

Cited By ~ 41

Author(s):

C. S. Tan ◽

C. F. Drury ◽

J. D. Gaynor ◽

T. W. Welacky

Keyword(s):

Water Table ◽

Surface Runoff ◽

Management System ◽

Management Practices ◽

Drainage Water ◽

Tile Drainage ◽

Nitrate Contamination ◽

Runoff Water ◽

Runoff Events ◽

Water Table Control

Corn management practices, incorporating annual ryegrass intercrop, conservation tillage and water table management, were evaluated to reduce herbicide and N0−3 losses through surface runoff and tile drainage. The integrated management system being developed at Harrow in S.W. Ontario reduced herbicide input 50% by banding the chemical over the seed row. Runoff events close to herbicide application contained high concentrations of atrazine, metribuzin and metolachlor. However, the volume of runoff was low during the 1991 growing season, therefore herbicide loss was low (<2% of applied). The three herbicides rapidly dissipated in the soil so that subsequent runoff events transported little herbicide in the runoff water. The total quantity of de-ethyl atrazine loss was lower from soil saver than moldboard plow. No water table control or intercrop effects were found in 1991 for herbicide loss because of the drought Tile drainage resulted in a greater volume of water and loss of N0−3 than with surface runoff. Consequently, over 97% of the total N0−3 loss occurred through tile drainage. The flow weighted N0−3 concentration in tile drainage water was 22.5 mg N L−1 for the drainage treatments and 15.1 mg N L−1 for the water table control treatments from Nov. 1, 1991 till April 30, 1992. During this time period, N0−3 loss through tile drainage was 57.8 kg N ha−1 from the drainage treatments and 36.3 kg N ha−1 from the water table control treatments. Therefore, the water table control treatment reduced the flow weighted N0−3 concentration in tile drainage water by 33% and total N0−3 loss by 37%. The water table control treatments combined with soil saver tillage resulted in lower concentrations and losses of N0−3 than with any other treatments.

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Corn Stover Removal Responses on Soil Test P and K Levels in Coastal Plain Ultisols

Sustainability ◽

10.3390/su13084401 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4401

Author(s):

Jeffrey M. Novak ◽

James R. Frederick ◽

Don W. Watts ◽

Thomas F. Ducey ◽

Douglas L. Karlen

Keyword(s):

Coastal Plain ◽

Nutrient Removal ◽

Fertilizer Application ◽

First Year ◽

Soil Test ◽

Concentration Data ◽

Extractable P ◽

K Fertilizer ◽

Soil Test P ◽

K Concentration

Corn (Zea mays L.) stover is used as a biofuel feedstock in the U.S. Selection of stover harvest rates for soils is problematic, however, because excessive stover removal may have consequences on plant available P and K concentrations. Our objective was to quantify stover harvest impacts on topsoil P and K contents in the southeastern U.S. Coastal Plain Ultisols. Five stover harvest rates (0, 25, 50, 75 and 100% by wt) were removed for five years from replicated plots. Grain and stover mass with P and K concentration data were used to calculate nutrient removal. Mehlich 1 (M1)-extractable P and K concentrations were used to monitor changes within the soils. Grain alone removed 13–15 kg ha−1 P and 15–18 kg ha−1 K each year, resulting in a cumulative removal of 70 and 85 kg ha−1 or 77 and 37% of the P and K fertilizer application, respectively. Harvesting stover increased nutrient removal such that when combined with grain removed, a cumulative total of 95% of the applied P and 126% of fertilizer K were taken away. This caused M1 P and K levels to decline significantly in the first year and even with annual fertilization to remain relatively static thereafter. For these Ultisols, we conclude that P and K fertilizer recommendations should be fine-tuned for P and K removed with grain and stover harvesting and that stover harvest of >50% by weight will significantly decrease soil test M1 P and K contents.

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EFFECTS OF NITROGEN, PHOSPHORUS, POTASSIUM, AND MANURE FACTORIALLY APPLIED TO POTATOES IN A LONG-TERM STUDY

Canadian Journal of Soil Science ◽

10.4141/cjss73-031 ◽

1973 ◽

Vol 53 (2) ◽

pp. 205-211 ◽

Cited By ~ 13

Author(s):

W. N. BLACK ◽

R. P. WHITE

Keyword(s):

Solanum Tuberosum L ◽

Starch Content ◽

Leaf Tissue ◽

Soil Test ◽

Term Study ◽

Long Term Study ◽

Soil Test P ◽

Yield Responses ◽

Nitrogen Phosphorus

The effects of N, P, K, and manure factorially applied to potato (Solanum tuberosum L.) yields, starch content, and soil and tissue nutrient levels were evaluated on continuous plots over 12 yr in a 4-yr potato, grain, hay, hay rotation. Although yield responses were observed with N, P, and K applications, manure application substantially increased yields above yield levels due to applied N, P, and K. Increasing rates of KCl strongly depressed tuber starch contents. Soil test P and K levels increased with repeated fertility applications, and leaf tissue levels were increased with N, P, and K treatments.

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Effect on Colwell soil-test P of storing air-dry soil samples at room temperature for up to seventeen years

European Journal of Soil Science ◽

10.1111/j.1365-2389.1994.tb00486.x ◽

1994 ◽

Vol 45 (1) ◽

pp. 53-57

Author(s):

M.D.A. BOLLAND ◽

J. DHALIWAL ◽

J.W. BOWDEN ◽

D.G. ALLEN

Keyword(s):

Room Temperature ◽

Soil Samples ◽

Soil Test ◽

Soil Test P ◽

Dry Soil

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Relationship of soil phosphorus fractions to phosphorus soil tests and fertilizer response

Canadian Journal of Soil Science ◽

10.4141/s02-079 ◽

2003 ◽

Vol 83 (4) ◽

pp. 443-449 ◽

Cited By ~ 6

Author(s):

R. H. McKenzie ◽

E. Bremer

Keyword(s):

Available P ◽

Soil Test ◽

Strongly Correlated ◽

P Fractions ◽

Soil Tests ◽

Fertilizer Response ◽

Inorganic P ◽

Soil P ◽

P Fertilizer ◽

Soil Test P

Soil tests for available P may not be accurate because they do not measure the appropriate P fraction in soil. A sequential extraction technique (modified Hedley method) was used to determine if soil test P methods were accurately assessing available pools and if predictions of fertilizer response could be improved by the inclusion of other soil P fractions. A total of 145 soils were analyzed from field P fertilizer experiments conducted across Alberta from 1991 to 1993. Inorganic P (Pi) removed by extraction with an anion-exchange resin (resin P) was highly correlated with the Olsen and Kelowna-type soil test P methods and had a similar relationship with P fertilizer response. No appreciable improvement in the fit of available P with P fertilizer response was achieved by including any of the less available P fractions in the regression of P fertilizer response with available P. Little Pi was extractable in alkaline solutions (bicarbonate and NaOH), particularly in soils from the Brown and Dark Brown soil zones. Alkaline fractions were the most closely related to resin P, but the relationship depended on soil zone. Inorganic P extractable in dilute HCl was most strongly correlated with soil pH, reflecting accumulation in calcareous soils, while Pi extractable in concentrated acids (HCl and H2SO4) was most strongly correlated with clay concentration. A positive but weak relationship as observed between these fractions and resin P. Complete fractionation of soil P confirmed that soil test P methods were assessing exchangeable, plant-available P. Key words: Hedley phosphorus fractionation, resin, Olsen, Kelowna

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Finnish trends in phosphorus balances and soil test phosphorus

Agricultural and Food Science ◽

10.2137/145960607784125339 ◽

2008 ◽

Vol 16 (4) ◽

pp. 301 ◽

Cited By ~ 18

Author(s):

R. UUSITALO ◽

E. TURTOLA ◽

J. GRÖNROOS

Keyword(s):

Agricultural Soils ◽

Animal Production ◽

Plant Production ◽

Major Influence ◽

Soil Test ◽

P Loss ◽

P Concentration ◽

Soil Test P ◽

Soil Test Phosphorus ◽

Yield Responses

Soil test phosphorus (P) concentration has a major influence on the dissolved P concentration in runoff from agricultural soils. Thus, trends in soil test P partly determine the development of pollution potential of agricultural activities. We reviewed the changes of soil test P and P balances in Finnish agriculture, and assessed the current setting of P loss potential after two Agri-Environmental Programs. Phosphorus balance of the Finnish agriculture has decreased from +35 kg ha1 of the 1980s to about +8 kg P ha1 today. As a consequence, the 50-yr upward trend in soil test P concentrations has probably levelled out in the late 1990s, as suggested by sampling of about 1600 fields and by a modelling exercise. For the majority of our agricultural soils, soil test P concentrations are currently at a level at which annual P fertilization is unlikely to give measurable yield responses. Soils that benefit from annual P applications are more often found in farms specialized in cereal production, whereas farms specialized in non-cereal plant production and animal production have higher soil test P concentrations. An imbalance in P cycling between plant (feed) and animal production is obvious, and regional imbalances are a result of concentration of animal farms in some parts of the country. A major concern in future will be the fate of manure P in those regions where animal production intensity is further increasing.;

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Analysis of the Impact of the Type of Sampling of Representative Properties on the Results of Mass Appraisal

Folia Oeconomica Stetinensia ◽

10.2478/foli-2020-0041 ◽

2020 ◽

Vol 20 (2) ◽

pp. 152-167

Author(s):

Sebastian Gnat

Keyword(s):

Real Estate ◽

Random Sampling ◽

Simple Random Sampling ◽

Multiple Regression Model ◽

Stratified Sampling ◽

Sampling Errors ◽

Real Estate Valuation ◽

Simple Sampling ◽

The Impact ◽

Mean Square Errors

Abstract Research background: Mass valuation is a process in which many properties are valued simultaneously with a uniform approach. An example of a procedure used for mass real estate valuation is the Szczecin Algorithm of Real Estate Mass Appraisal (SAREMA), which can be developed into a multiple regression model. The algorithm is based on a set of drawn representative properties. This set determines, inter alia, the quality of obtained valuations. Purpose: The objective of the study is to verify the hypothesis whether changing the method of sampling representative properties from the originally used simple random sampling to stratified sampling improves the results of the SAREMA econometric variant. Research methodology: The article presents a study that uses two methods of representative properties sampling – simple random sampling and stratified sampling. Errors of the models of valuation created taking into account both methods of sampling and different number of representative properties are compared. A key aspect of the survey is the choice of a better sampling method. Results: The study has shown that stratified sampling improves valuation results and, more specifically, allows for lower root mean square errors. Stratified sampling yielded better results in the initial phase of the study with more observations, but reducing the percentage of strata participating in the draws, despite the increase in RMSE, guaranteed lower errors than the corresponding results based on simple sampling in all variants of the study. Novelty: The article confirms the possibility of improving the results of mass property valuation by changing the scheme of representative properties sampling. The results allowed for the conclusion that stratified sampling is a better way of creating a set of representative properties.

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