Long-term Changes in Grassland Soil Phosphorus with Fertilizer Application and Withdrawal

A mathematical description is presented of the effects through time of phosphorus fertilizer application on the growth of Stylosanthes hamata cv. Verano and on changes in extractable soil phosphorus on a red and a yellow earth in the semi-arid tropics. For the five years of observations, the models used provided reasonable descriptions of both aspects. It was not possible, however, to clearly demonstrate which of two functions tested better described the decreasing effectiveness of phosphorus with time. The simpler exponential function provided as good a fit to the yield data as did the function proposed by Barrow, whilst for the extractable phosphorus data the latter did explain a significantly higher proportion of the variance, but its coefficients could not be estimated with great precision. The results show that the phosphorus requirements of such pastures on these soils are modest. Extractable soil phosporus levels of approximately 12 �g g-1 in either 0.005 M H2SO4 or 0.5 M NaHCO3 are indicated as being adequate to ensure near-maximum yields of the legume. Long-term maintenance fertilizer needs as predicted by the models are discussed.

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Long-term crop rotation and fertilizer effects on phosphorus transformations: II. In a Luvisolic soil

Canadian Journal of Soil Science ◽

10.4141/cjss92-048 ◽

1992 ◽

Vol 72 (4) ◽

pp. 581-589 ◽

Cited By ~ 41

Author(s):

R. H. McKenzie ◽

J. W. B. Stewart ◽

J. F. Dormaar ◽

G. B. Schaalje

Keyword(s):

Sodium Bicarbonate ◽

Sequential Extraction ◽

Sodium Hydroxide ◽

Crop Rotation ◽

Soil Phosphorus ◽

Fertilizer Application ◽

P Fractions ◽

Soil P ◽

P Transformations

The effects of different cropping systems, fertilizer, and lime on soil phosphorus (P) dynamics in soils developed under forest vegetation have received little attention. The objective of this study was to develop an understanding of P fractions and transformations in long-term rotation plots on a Luvisolic soil at Breton, Alberta. Results have shown that crop rotation and fertilizer application have affected more inorganic soil phosphorus (Pi) and organic phosphorus (Po) fractions, as determined by a sequential extraction procedure. Continuously cropped treatments, which had not received fertilizer, resulted in P drawdown of resin-extractable Pi (resin-Pi), sodium bicarbonate-extractable Pi (bicarb-Pi), sodium hydroxide-extractable Pi (NaOH-Pi), sodium bicarbonate-extractable Po (bicarb-Po), sodium hydroxide-extractable Po (NaOH-Po) and hydrochloric acid-extractable Pi (HCl-Pi) fractions. Only the residual-P fraction (insoluble Pi and stable Po forms) was unaffected. Addition of fertilizer had an effect on all P fractions except the NaOH-Po fraction. Phosphorus fertilizer treatments positively affected the Pi fractions and N fertilizer positively affected the bicarb-Po fraction. Lime application affected soil pH, which lowered NaOH-Pi levels and increased HCl-Pi levels through formation of more stable calcium phosphate compounds. Addition of lime also resulted in lower bicarb-Po levels. Cropping without using phosphate fertilizer has resulted in a 30–40% decline in total-P in the Breton plots in the Ap horizon. Continuous cropping, with a forage crop in the rotation, coupled with modest N and P fertilizer application, had the most positive effects on P cycling and transformations. Summerfallow had no apparent beneficial effects on P transformations. Key words: Soil P transformations, Luvisolic soil, P bioavailability, sequential extraction

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Long-term changes in soil phosphorus status related to P budgets under maize monoculture and mineral P fertilization

Soil Use and Management ◽

10.1111/j.1475-2743.2010.00287.x ◽

2010 ◽

Vol 26 (3) ◽

pp. 354-364 ◽

Cited By ~ 46

Author(s):

A. J. Messiga ◽

N. Ziadi ◽

D. Plénet ◽

L.-E. Parent ◽

C. Morel

Keyword(s):

Soil Phosphorus ◽

P Fertilization ◽

Long Term Changes ◽

Phosphorus Status

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Influence of long-term fertilizer application on changes of the content of Mehlich-3 estimated soil macronutrients

Plant Soil and Environment ◽

10.17221/930/2013-pse ◽

2014 ◽

Vol 60 (No. 4) ◽

pp. 151-157 ◽

Cited By ~ 14

Author(s):

M. Kulhánek ◽

J. Balík ◽

J. Černý ◽

F. Vašák ◽

Š. Shejbalová

Keyword(s):

Sewage Sludge ◽

Crop Rotation ◽

Field Experiments ◽

Soil Phosphorus ◽

Farmyard Manure ◽

Magnesium Content ◽

Fertilizer Application ◽

Climatic Conditions ◽

Total Magnesium

The aim of this work is to evaluate the changes of Mehlich 3 – P, K, Ca and Mg contents in soil during a long-term field experiments with sewage sludge, farmyard manure (FYM) and mineral NPK (NPK) application, compared to the control non-fertilized treatment. The experiment was established at the Humpolec and Suchdol sites (Czech Republic). Potatoes, wheat and barley were grown in crop rotation. Fertilizing system was based on the same nitrogen dose of 330 kg N/ha per one crop rotation. Archive soil samples from the beginning of the experiment (1996) and from the end of each year’s crop rotation (1999, 2002, 2005, 2008 and 2011) were analyzed. In spite of the different soil-climatic conditions of the studied sites, very similar tendencies of P, K, Ca and Mg contents changes after the fertilizing systems used were observed in the soil. In case of the same nitrogen dose (330 kg N/ha), sewage sludge appeared to be better source of bioavailable soil phosphorus compared to the farmyard manure and NPK. On the contrary, FYM was a better source of bioavailable potassium and magnesium, despite the lower total magnesium content in FYM. The NPK treatment was the best long-term source of bioavailable potassium.

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Modelling long-term changes in soil phosphorus and carbon under contrasting fertiliser and grazing management in New Zealand hill country

Journal of New Zealand Grasslands ◽

10.33584/jnzg.2019.81.397 ◽

2019 ◽

pp. 171-178 ◽

Cited By ~ 2

Author(s):

Franco Bilotto ◽

Ronaldo Vibart ◽

Alec Mackay ◽

Des Costall

Keyword(s):

New Zealand ◽

Current Knowledge ◽

Soil Phosphorus ◽

National Level ◽

Transfer Model ◽

Soil C ◽

Hill Country ◽

C Stocks ◽

Long Term Changes

Soil carbon (C) stocks under permanent New Zealand pastures vary with slope and aspect due to differences in primary production, animal behaviour and nutrient return. An existing nutrient transfer model was extended using a web-based, general-purpose modelling tool to simulate long-term changes in soil phosphorus (P) and C in hill country under contrasting fertiliser and sheep stocking regimes. Three self-contained farmlets were examined: no P applied; 125 kg single superphosphate (SSP)/ha/year; and 375 kg SSP/ha/year, since 1980. The refined spatial model was able to simulate P and C distribution with varying slopes and aspects. For example, the mean annual changes in soil P and C were greater on low slopes and eastern aspects than on the other two slope and aspect positions, consistent with observed changes in these nutrients. However, the model overestimated changes in soil C, which highlighted both gaps in current knowledge and key factors influencing change in soil C stocks. Understanding the spatial patterns of soil C across the landscape will be critical in the design of soil C monitoring regimes, should soil C stocks be considered at a national level as a sink or source of CO2 emissions.

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Long-term effects of fertilizers and manure application on the forms and availability of soil phosphorus

Canadian Journal of Soil Science ◽

10.4141/cjss95-040 ◽

1995 ◽

Vol 75 (3) ◽

pp. 281-285 ◽

Cited By ~ 35

Author(s):

Thi Sen Tran ◽

Adrien N’dayegamiye

Keyword(s):

Soil Phosphorus ◽

Fertilizer Application ◽

P Uptake ◽

Cattle Manure ◽

Organic P ◽

Manure Application ◽

Soil P ◽

P Fertilizer ◽

Labile P

Long-term application of cattle manure and fertilizer can affect the forms and availability of soil phosphorus. This cumulative effect was evaluated on Le Bras silt loam (Humic Gleysol) cultivated with silage corn (Zea mays L.). In this long-term trial, treatments were arranged in a split-plot design, with dairy cattle manure applied at 0 and 20 Mg ha−1 as the main factor. The subplots consisted of six fertilizer treatments (NK, PK, NP, NPK, NPKMg and the unfertilized check). Fertilizer rates for silage corn were 150, 100, 150 and 40 kg ha−1 N, P205, K20 and Mg, respectively. The N fertilizer rate was reduced to 100 kg N ha−1 in manured plots. Soil inorganic P (Pi) and organic P (Po) fractions were sequentially extracted by resin, NaHCO3, NaOH, HCl and a final H2SO4 wet digestion of the residue. On average, labile P extracted by resin and NaHCO3 represented 17% of the total P (Pt); moderately labile NaOH-Pi and Po more than 40%; and stable P 36%. Application of manure and fertilizers increased significantly resin-, NaHCO3-, NaOH-Pi and Pt. However, NaOH-Po was decreased by P fertilizer application in NPK and NPKMg treatments, while long-term manure application maintained this Po pool in the soil. Stable P fractions were not affected by fertilization or by manuring. In all 6 yr of the study, P uptake by silage corn was significantly increased both by long-term N and P fertilizer application and also by manure incorporation. Phosphorus uptake by corn was highly related to all labile and moderately labile Pi fractions and Pt. Long-term application of dairy manure at a rate of 20 t ha−1 increased soil Pi forms and maintained Po fractions. Key words: Inorganic labile P, organic P, soil-P fractionation, P uptake, silage corn

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