Bayesian spatio-temporal modeling of soil phosphorus in Britany in western France (1995-2014) with INLA-SPDE

Soil phosphorus (P) is one of the most critical elements for Earth&#8217;s ecosystem. P is a component of the complex nucleic acid structure of plants, which regulates protein synthesis, plants deficient in P are stunted in growth and lead to diseases. In practice, P is most often the element responsible for eutrophication problems in freshwater meanwhile, and it is considered the macronutrient most frequently as the element limiting eutrophication because many blue-green algae are able to use atmospheric N2. Since the Second World War overuse application of fertilizer P has leaded to lots of serious environmental problems such as eutrophication of water body.Soil P was affected by several factors including climate, geology, time, anthropogenic activities (irrigation, industrial emission, fertilizer application, crop planting pattern etc.) and so on. This makes soil P varied in a very complex manner on both spatial and time dimension and thus increases the difficulty of estimating spatio-temporal variation of soil P. Therefore, a flexible framework is necessary for modelling spatio-temporal variation of soil P.To explore spatio-temporal variation of soil available P, we propose a Bayesian hierarchical spatio-temporal model using Integrated Nested Laplace Approximation with Stochastic Partial Differential Equation approach (INLA-SPDE). The study was conducted on phosphorus measured by Olsen (P Olsen) and Dyer (P Dyer) methods in Britany (western France) from 1995 to 2014 with data of more than 30,000 samples of France national soil test database (BDAT).The INLA-SPDE method exploits the Laplace approximation in Bayesian latent-Gaussian models and does not require generating samples from the posterior distribution. Hence, it can often be used for quite large data sets at reasonable computational expense. It could provide approximate marginal (posterior) distributions over all states and parameters. In this study, the constructed model includes of several components such as spatial varying trend, space varying temporal trend, effects of covariates, and residual with space-time dependent variation.Regardless the method of quantifying phosphorus, the results indicated that the mean content of soil available P decreased between 1995 and 2014 in Britany. Our model explained 49.5% of variance of spatio-temporal variation of P Olsen in Britany in external validation dataset. For P Dyer, our model explained 50% of variance in external validation dataset. The purely spatial effects shown that the available P in west of Britany was higher than east part. Our study could contribute to better soil management and environmental protection. Further study still needed to include more related factors into the model to improve the model performance and detected more related factors (such as soil management measures) which have important effects on spatio-temporal variation of available P in soil.

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Comparison of soil phosphorus and phosphatase activity under long-term no-tillage and maize residue management

Plant Soil and Environment ◽

10.17221/307/2019-pse ◽

2019 ◽

Vol 65 (No. 8) ◽

pp. 408-415 ◽

Cited By ~ 1

Author(s):

Xiaozhu Yang ◽

Xuelian Bao ◽

Yali Yang ◽

Yue Zhao ◽

Chao Liang ◽

...

Keyword(s):

Soil Phosphorus ◽

Soil Layer ◽

Residue Management ◽

Available P ◽

No Tillage ◽

Organic P ◽

Inorganic P ◽

Phosphatase Activities ◽

Soil P ◽

Soil Available P

The migration and transformation of soil phosphorus (P) are essential for agricultural productivity and environmental security but have not been thoroughly elucidated to date. A 10-year field study was conducted to explore the effects of conventional tillage (CT) and no-tillage with maize residue management (NT-0, NT-33%, NT-67% and NT-100%) on P contents and phosphatase activities in soil layers (0–5, 5–10, 10–20 and 20–40 cm). The results showed that soil available P content and phosphatase activities were higher in no-tillage with maize residue than CT. Soil moisture and pH were significantly positively correlated with soil available P. Higher organic P contents and lower inorganic P contents in the 0–5 cm soil layer were found in the treatment NT-67% compared with other treatments. According to the structure equation model, the source of available P was inorganic P in NT-33%, while organic P in NT-67%. This study demonstrated that the variation of dominant mechanisms involved in soil P migration and transformation were dependent on residue input amounts, and NT-67% might play an important role in the maintenance and transformation of soil organic P.

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Using a One-Dimensional Convolutional Neural Network on Visible and Near-Infrared Spectroscopy to Improve Soil Phosphorus Prediction in Madagascar

Remote Sensing ◽

10.3390/rs13081519 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1519

Author(s):

Kensuke Kawamura ◽

Tomohiro Nishigaki ◽

Andry Andriamananjara ◽

Hobimiarantsoa Rakotonindrina ◽

Yasuhiro Tsujimoto ◽

...

Keyword(s):

Neural Network ◽

Convolutional Neural Network ◽

Near Infrared ◽

Soil Phosphorus ◽

Predictive Ability ◽

Available P ◽

Accurate Estimation ◽

One Dimensional ◽

P Content ◽

Soil Available P

As a proximal soil sensing technique, laboratory visible and near-infrared (Vis-NIR) spectroscopy is a promising tool for the quantitative estimation of soil properties. However, there remain challenges for predicting soil phosphorus (P) content and availability, which requires a reliable model applicable for different land-use systems to upscale. Recently, a one-dimensional convolutional neural network (1D-CNN) corresponding to the spectral information of soil was developed to considerably improve the accuracy of soil property predictions. The present study investigated the predictive ability of a 1D-CNN model to estimate soil available P (oxalate-extractable P; Pox) content in soils by comparing it with partial least squares (PLS) and random forest (RF) regressions using soil samples (n = 318) collected from natural (forest and non-forest) and cultivated (upland and flooded rice fields) systems in Madagascar. Overall, the 1D-CNN model showed the best predictive accuracy (R2 = 0.878) with a highly accurate prediction ability (ratio of performance to the interquartile range = 2.492). Compared to the PLS model, the RF and 1D-CNN models indicated 4.37% and 23.77% relative improvement in root mean squared error values, respectively. Based on a sensitivity analysis, the important wavebands for predicting soil Pox were associated with iron (Fe) oxide, organic matter (OM), and water absorption, which were previously known wavelength regions for estimating P in soil. These results suggest that 1D-CNN corresponding spectral signatures can be expected to significantly improve the predictive ability for estimating soil available P (Pox) from Vis-NIR spectral data. Rapid and accurate estimation of available P content in soils using our results can be expected to contribute to effective fertilizer management in agriculture and the sustainable management of ecosystems. However, the 1D-CNN model will require a large dataset to extend its applicability to other regions of Madagascar. Thus, further updates should be tested in future studies using larger datasets from a wide range of ecosystems in the tropics.

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Effect of Soil Available Phosphorus Levels on Chickpea (Cicer arietinum L.) - Rhizobia Symbiotic Association

Legume Research - An International Journal ◽

10.18805/lr-524 ◽

2020 ◽

Author(s):

Khadraji Ahmed ◽

Bouhadi Mohamed ◽

Ghoulam Cherk

Keyword(s):

Cicer Arietinum ◽

Available P ◽

Phosphorus Concentration ◽

Available Phosphorus ◽

Symbiotic Association ◽

P Deficiency ◽

Soil P ◽

P Content ◽

Nodule Biomass ◽

Soil Available P

Background: Growing chickpea (Cicer arietinum) plants is affected by several environmental constraints as osmotic stress and nutrients deficiency particularly phosphorus (P). For other legume species, it was confirmed that P deficiency affects negatively their rhizobial symbiosis. The purpose of this study was to assess the effect of soil available P level on chickpea-rhizobia symbiosis under field conditions at Oualidia region of Morocco. Methods: Ten farmers’ fields with different soil available P levels were considered to carry out this study based on samples of 10 plants per plot. Result: The results showed that the plants from soil 7, with the lowest pH and the highest available P level (23.52ppm), presented high shoot dry weight (38.3 g/plant). Meanwhile the soil 5 with the lowest available P content showed low plant growth. The shoot P content was positively linked to soil P level but nodule biomass showed an irregular variation with soil available P level. Furthermore, it was confirmed that adequate plant P nutrition results in high chickpea yield and it was the case for plants from soil 7 presenting a mean yield of 62 seeds per plant). Finally, strong correlation was noted between yield and phosphorus concentration in soil (r=0.94).

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Phosphate Adsorption Capacity and Organic Matter Effect on Dynamics of P Availability in Upland Ultisol and Lowland Inceptisol

Journal of Tropical Soils ◽

10.5400/jts.2011.v16i2.107-114 ◽

2013 ◽

Vol 16 (2) ◽

pp. 107-114

Author(s):

. Marsi ◽

. Sabaruddin

Keyword(s):

Organic Matter ◽

Fresh Water ◽

Water Soluble ◽

Available P ◽

Phosphate Adsorption ◽

P Availability ◽

Soil P ◽

Soil Available P ◽

Adsorption Desorption ◽

Desorption Capacity

Ultisols and Inceptisols were used to investigate the adsorption-desorption capacity of P and the effect of organic matter on the dynamics of P availability in tropical acid soils. The experiment consisted of two sub-experiments. Sub-experiment I was to study the adsorption-desorption capacity of Ultisols, Fresh-water lowland Inceptisols, and tidal-swamp Inceptisols. Therefore, surface soils (0 to 30 cm) of each tested soil were treated with 0, 10, 20, 30, 40, 60, 80, 100, 120, 140, 170, and 200 mg P kg-1 of soil. Sub-experiment II was to study the effects of organic matterapplication (0, 5, 10, and 15 Mg ha-1) on the dynamics of available P following 60d incubation under room temperature.P fertilizer application significantly affected water soluble-P (WSP) (p<0.01) and soil available P-Bray and Kurtz No. 1 (BKP) (p<0.01) in the three tested soils. The different response of both WSP and BKP confirmed that the soils tested in the current experiment had different soil P buffering capacity in the order of Tidal-lowlandInceptisol>Upland Ultisol>fresh-water Lowland Inceptisol. OM application increased the BKP in all tested soils as compared to the control. Differences in pattern of soil available P dynamics over time were detected between upland soil and two lowland soils used in the current experiment.Keywords: Adsorption-desorption, Inceptisols, organic matter, Ultisols

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Depletion, accumulation and availability of soil phosphorus in the Askov long-term field experiment

Soil Research ◽

10.1071/sr19203 ◽

2020 ◽

Vol 58 (2) ◽

pp. 117 ◽

Cited By ~ 1

Author(s):

Musibau O. Azeez ◽

Gitte Holton Rubæk ◽

Ingeborg Frøsig Pedersen ◽

Bent T. Christensen

Keyword(s):

Rock Phosphate ◽

Soil Phosphorus ◽

Available P ◽

Soil P ◽

Olsen P ◽

Extractable P ◽

P Application ◽

Plant Available P ◽

Water Extractable

Soil phosphorus (P) reserves, built up over decades of intensive agriculture, may account for most of the crop P uptake, provided adequate supply of other plant nutrients. Whether crops grown on soils with reduced supply of other nutrients obtain similar use-efficiency of soil P reserves remains unclear. In treatments of the Askov Long-Term Experiment (initiated in 1894 on light sandy loam), we quantified changes in soil total P and in plant-available P (Olsen P, water extractable P and P offtake in wheat grains) when P-depleted soil started receiving P in rock phosphate and when P application to soil with moderate P levels ceased during 1997–2017. Additionally we studied treatments with soil kept unfertilised for >100 years and with soil first being P depleted and then exposed to surplus dressings of P, nitrogen (N) and potassium in cattle manure. For soil kept unfertilised for >100 years, average grain P offtake was 6 kg ha–1 and Olsen P averaged 4.6 mg kg–1, representing the lower asymptotic level of plant-available P. Adding igneous rock phosphate to severely P-depleted soil with no N fertilisation had little effect on Olsen P, water extractable P (Pw), grain yields and P offtake. For soils with moderate levels of available P, withholding P application for 20 years reduced contents of Olsen P by 56% (from 16 to 7 mg P kg–1) and of Pw by 63% (from 4.5 to 1.7 mg P kg–1). However, the level of plant-available P was still above that of unfertilised soil. Application of animal manure to P-depleted soil gradually raised soil P availability, grain yield and P offtake, but it took 20 years to restore levels of plant-available P. Our study suggests symmetry between rates of depletion and accumulation of plant-available P in soil.

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Changes in soil phosphorus balance and phosphorus-use efficiency under long-term fertilization conducted on agriculturally used Chernozem in Germany

Canadian Journal of Soil Science ◽

10.1139/cjss-2018-0061 ◽

2018 ◽

Vol 98 (4) ◽

pp. 650-662 ◽

Cited By ~ 2

Author(s):

Tetiana Medinski ◽

Dirk Freese ◽

Thomas Reitz

Keyword(s):

Soil Phosphorus ◽

Spring Barley ◽

Farmyard Manure ◽

Available P ◽

Phosphorus Use Efficiency ◽

P Fertilization ◽

Mineral N ◽

Efficient Treatment ◽

Soil P ◽

Use Efficiency

This study investigates changes in soil phosphorus (P) in different fertilization treatments applied since 1902 on Chernozem soil at a “Static Fertilization Experiment” in Germany. Total and plant-available soil P, and soil P balances were assessed at 0–30, 30–60, and 60–90 cm depth layers in unfertilized “Zero”, mineral “NK” and “NPK”, and combined mineral and organic “FYM + NK” (farmyard manure + NK) and “FYM + NPK” fertilization treatments. P-use efficiencies were determined for each crop in rotation (sugar beet, spring barley, potato, and winter wheat). The 110 yr of P fertilization at rates between 22 and 55 t ha−1 yr−1 resulted in a significant increase of available P contents. P stocks increased up to 60 cm depth. Total P accumulation comprised 1.4 t ha−1 for NPK, 1.3 t ha−1 for FYM + NK, and 3.1 t ha−1 for FYM + NPK. Crops cultivation without P fertilization in Zero and NK treatments resulted in negative P balances and reduction of available P below recommended levels. Reduction of mineral P application rates after 1981, along with crop variety-dependent yield increases, resulted in an improved P-use efficiency. An organic fertilization combined with mineral N and K fertilizers (FYM + NK) was found to be the most P-efficient treatment for Chernozem soils.

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Sensitivity of Three Phosphate Extraction Methods to the Application of Phosphate Species Differing in Immediate Plant Availability

Agronomy ◽

10.3390/agronomy9010029 ◽

2019 ◽

Vol 9 (1) ◽

pp. 29 ◽

Cited By ~ 4

Author(s):

Tobias Hartmann ◽

Iris Wollmann ◽

Yawen You ◽

Torsten Müller

Keyword(s):

Soil Phosphorus ◽

Extraction Methods ◽

Available P ◽

Plant Availability ◽

Soil P ◽

Low Concentrations ◽

High Sorption ◽

Phosphate Species ◽

Different Characteristics ◽

Plant Available P

Extractive tests for determining the plant-availability of soil phosphorus (P) give varying results due to the inherently different characteristics of the extraction solution. Generally, classical soil P tests such as the Olsen or calcium acetate/lactate (CAL) method do not give an indication on the total amount of plant available P, but merely give an indication of the equilibrium between soil and extraction solution. It is also not entirely clear which fractions of P are directly determined through the various methods of extraction, i.e., determined P must not be immediately plant available, as is the case for rock phosphate. It is therefore possible that extraction methods either over or under estimate the amount of P available for plant consumption. In this research, we compared three methods of soil P determination (CAL, Olsen and diffusive gradients in thin films (DGT)) with regards to their ability to determine P species (Ca(H2PO4)2, CaHPO4, Ca3(PO4)2 and Inositol-6-hexakisphosphate) added to soils of high sorption capacity, immediately after as well as two weeks after application. For each of the methods, it could be shown that sorption processes in the soil immediately (0 days incubation) fix P to a point where it is not extractable through any of the described methods. These sorption processes continue over time, leading to a further decrease of determined P. The acidic CAL extraction method gives higher results of extractable P compared to the Olsen method. Due to the extraction of Ca3(PO4)2, the CAL method may overestimate immediately plant-available P. The most suitable methods for the determination of immediately plant available P may therefore be the Olsen and DGT methods. Organic IP6 is not determined by any of the extraction methods. At low concentrations of soil P, the DGT method may fail to give results.

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Build-up in soil available P and yield response of spring wheat to seed-placed P in a 24-year study in the Brown Soil zone

Canadian Journal of Soil Science ◽

10.4141/cjss93-020 ◽

1993 ◽

Vol 73 (2) ◽

pp. 173-181 ◽

Cited By ~ 3

Author(s):

R. P. Zentner ◽

C. A. Campbell ◽

F. Selles

Keyword(s):

Spring Wheat ◽

Available P ◽

Yield Response ◽

Soil P ◽

Olsen P ◽

Leaf Stage ◽

Extractable P ◽

Soil Available P ◽

P Fertilizer ◽

Yield Responses

Producers in western Canada have applied phosphorus (P) fertilizer to annual crops for many years. This has increased soil available P and gradually decreased the expected yield response to P fertilization, but yield responses to small amounts of P placed with the seed are still reported regardless of soil available P levels. Controlled growth chamber studies suggest that the P responses should be most apparent during cool, wet springs. This 24-yr field study compared the yields of two fallow–spring wheat–spring wheat (F–W–W) systems, one fertilized with N and P each crop year, and the other fertilized with only N. The study, which was part of a long-term crop rotation experiment, was conducted on an Orthic Brown Chernozemic loam at Swift Current, Saskatchewan. Bicarbonate-extractable P (Olsen P) in the 0- to 15-cm depth in spring of the treatment receiving no P remained relatively constant (about 19 kg ha−1) throughout the study, while P fertilizer application at 6.5 kg ha−1 yr−1 increased extractable soil P by about 0.9 kg ha−1 yr−1. However, this increase in available P has not reduced yield responses to seed-placed P over the years. Regression analysis showed that yield response to P on fallow soil was positively related to temperature between emergence and the three-leaf stage and to precipitation at dough stage, but negatively related to precipitation near seeding time. For wheat grown on stubble, response to P was negatively related to temperature between 10 and 16 June (i.e., about the three- to four-leaf stage) and positively to precipitation received at anthesis stage. We concluded that, although available P in prairie soils has probably increased in recent years, producers can still expect to receive a 10% yield increase when small amounts of P are applied with the seed.Key words: Crop rotations, bicarbonate-extractable P, Olsen P, temperature effects, effect of precipitation

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Evaluation on a Novel Phosphorus Fractionation Method in Acid Soils

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.272 ◽

2012 ◽

Vol 204-208 ◽

pp. 272-278

Author(s):

Hong Jun Lei ◽

Xin Liu ◽

Bei Dou Xi ◽

Duan Wei Zhu

Keyword(s):

Soil Phosphorus ◽

Acid Soils ◽

Phosphorus Fractionation ◽

Red Soil ◽

Water Bath ◽

Available P ◽

Control Treatment ◽

Available Phosphorus ◽

Soil P ◽

The Difference

Phosphorous fractionation is a method developed to estimate sizes of readily soil available P pool, soil P sub-pools and their ability to replenish the available P. Three types of acid soils (1aterite red soil, yellow red soil and brown red soil) were used in pot experiment under a rain-shelter condition to investigate the effect of lime amendment on P fractions and their bioavailability by plant of broad bean. A novel phosphorus fractionation scheme was developed and used to study the phosphorus fractionation of the tested soils compared with the two typical soil phosphorus fractionation schemes, adopting a series of extractants such as 0.25mol L-1 NaHCO3, 1h (for Ca2-P), 0.5mol L-1 NH4F (pH8.5), 1h (for Al-P), 0.7mol L-1 NaClO, pH 8.05, 85°C water bath 30min (for Org-P), 0.1mol L-1 NaOH-0.1Na2CO3, 4h (for Fe-P), 1mol L-1 NaOH, 85°C water bath 1h (for O-Al-P), 0.3 mol L-1 Na-citrate-0.5 g Na2S2O4 -0.5 mol L-1 NaOH, 85°C water bath 15min (for O-Fe-P), 0.25mol L-1 H2SO4, 1h (for Ca10-P). Main results are obtained just as follows: besides Ca2-P, Al-P, Fe-P and O-Fe-P are potentially available phosphorus resource. Although O-P reflects the difference of P between lime and control treatment well, when it appears as a whole, it needs further subdivision to reflect soil phosphorus biologically availability difference better.

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Surface soil phosphorus and phosphatase activities affected by tillage and crop residue input amounts

Plant Soil and Environment ◽

10.17221/437/2010-pse ◽

2011 ◽

Vol 57 (No. 6) ◽

pp. 251-257 ◽

Cited By ~ 42

Author(s):

J.B. Wang ◽

Z.H. Chen ◽

L.J. Chen ◽

A.N. Zhu ◽

Z.J. Wu

Keyword(s):

Crop Residue ◽

Soil Phosphorus ◽

Conventional Tillage ◽

Available P ◽

Inorganic Pyrophosphatase ◽

Organic P ◽

Phosphatase Activities ◽

Soil P ◽

No Till ◽

Total P

The effects of tillage and residue input amounts on soil phosphatase (alkaline phosphomonoesterase ALP, acid phosphomonoesterase ACP, phosphodiesterase PD, and inorganic pyrophosphatase IPP) activities and soil phosphorus (P) forms (total P, organic P, and available P) were evaluated using soils collected from a three-year experiment. The results showed that no-till increased soil total and organic P, but not available P as compared to conventional tillage treatments. Total P was increased as inputs of crop residue increased for no-till treatment. There were higher ALP and IPP activities in no-till treatments, while higher PD activity was found in tillage treatments and tillage had no significant effect on ACP activity. Overall phosphatase activities increased with an increase of crop residue amounts. Soil total P was correlated negatively with PD activity and positively with other phosphatase activities. Organic P had a positive correlation with ACP activity, but a negative correlation with PD activity. Available P had no significant correlation with phosphatase activities. Our data suggests that no-till and residue input could increase soil P contents and enhance the activities of phosphatase.

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