Global patterns and drivers of soil total phosphorus concentration

Abstract. Soils represent the largest phosphorus (P) reserves on land and determining the amount is a critical first step for identifying sites where ecosystem functioning is potentially limited by P availability. However, global patterns and predictors of soil total P concentration remain poorly understood. To address this knowledge gap, we constructed a database of the total P concentration of 5,275 distributed globally natural soils. We quantified the relative importance of 13 soil-forming variables in predicting soil total P concentration and then made further predictions at the global scale using a random forest approach. Soil total P concentration varied significantly among parent material types, soil orders, biomes, and continents, and ranged widely from 1.4 to 9,630.0 (median 430.0 and mean 570.0) mg kg−1 across the globe. About two-thirds (65 %) of the global variation was accounted for by the 13 variables that we selected, among which soil organic carbon concentration, parent material, mean annual temperature, and soil sand content were the most important. While global predictions of soil total P concentration increased significantly with latitude, they varied largely among regions with similar latitudes due to regional differences in parent material, topography, and/or climate conditions. Global soil P stocks (excluding Antarctica) were estimated to be 26.8 ± 3.1 (mean ± standard deviation) Pg and 62.2 ± 8.9 Pg (1 Pg = 1 × 1015 g) in the topsoil (0–30 cm) and subsoil (30–100 cm), respectively. Our global map of soil total P concentration as well as the underlying drivers of soil total P concentration can be used to constraint Earth system models that represent the P cycle and to inform quantification of global soil P availability. Raw datasets and global maps generated in this study are available at https://doi.org/10.6084/m9.figshare.14583375 (He et al., 2021).

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Global patterns and drivers of soil total phosphorus concentration

Earth System Science Data ◽

10.5194/essd-13-5831-2021 ◽

2021 ◽

Vol 13 (12) ◽

pp. 5831-5846

Author(s):

Xianjin He ◽

Laurent Augusto ◽

Daniel S. Goll ◽

Bruno Ringeval ◽

Yingping Wang ◽

...

Keyword(s):

Parent Material ◽

Phosphorus Concentration ◽

Mean Annual Temperature ◽

P Availability ◽

Soil P ◽

Soil P Availability ◽

P Concentration ◽

Organic Carbon Concentration ◽

Global Patterns ◽

Total P

Abstract. Soil represents the largest phosphorus (P) stock in terrestrial ecosystems. Determining the amount of soil P is a critical first step in identifying sites where ecosystem functioning is potentially limited by soil P availability. However, global patterns and predictors of soil total P concentration remain poorly understood. To address this knowledge gap, we constructed a database of total P concentration of 5275 globally distributed (semi-)natural soils from 761 published studies. We quantified the relative importance of 13 soil-forming variables in predicting soil total P concentration and then made further predictions at the global scale using a random forest approach. Soil total P concentration varied significantly among parent material types, soil orders, biomes, and continents and ranged widely from 1.4 to 9630.0 (median 430.0 and mean 570.0) mg kg−1 across the globe. About two-thirds (65 %) of the global variation was accounted for by the 13 variables that we selected, among which soil organic carbon concentration, parent material, mean annual temperature, and soil sand content were the most important ones. While predicted soil total P concentrations increased significantly with latitude, they varied largely among regions with similar latitudes due to regional differences in parent material, topography, and/or climate conditions. Soil P stocks (excluding Antarctica) were estimated to be 26.8 ± 3.1 (mean ± standard deviation) Pg and 62.2 ± 8.9 Pg (1 Pg = 1 × 1015 g) in the topsoil (0–30 cm) and subsoil (30–100 cm), respectively. Our global map of soil total P concentration as well as the underlying drivers of soil total P concentration can be used to constraint Earth system models that represent the P cycle and to inform quantification of global soil P availability. Raw datasets and global maps generated in this study are available at https://doi.org/10.6084/m9.figshare.14583375 (He et al., 2021).

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Prediction of phosphorus concentration in tile-drainage water from the Montreal Lowlands soils

Canadian Journal of Soil Science ◽

10.4141/s02-029 ◽

2003 ◽

Vol 83 (1) ◽

pp. 73-87 ◽

Cited By ~ 17

Author(s):

S. Beauchemin ◽

R. R. Simard ◽

M. A. Bolinder ◽

M. C. Nolin ◽

D. Cluis

Keyword(s):

Management Practices ◽

Drainage Water ◽

Tile Drainage ◽

Phosphorus Concentration ◽

Surface Soils ◽

Drainage Systems ◽

Soil P ◽

P Concentration ◽

Soil Units ◽

Total P

Subsurface drainage systems can be a significant pathway for P transfer from some soils to surface waters. The objective of the study was to determine P concentration in tile-drainage water and its relationship to P status in surface soils (A horizons) from an intensively cultivated area in the Montreal Lowlands. The profiles of 43 soil units were characterized for their P contents and pedogenic properties. Tile-drainage water P concentrations were monitored over a 3-y r period on a weekly basis on 10 soil units, and four times during each growing season for the other 33 units. The soil units were grouped into lower and higher P sorbing soils using multiple discriminant equations developed in an earlier related study. The A horizons of the lower P sorbing soils had an elevated P saturation degree [mean Mehlich(III) P/Al = 17%] associated with total P concentrations in tile-drainage water consistently greater than the surface water quality standard of 0.03 mg total P L-1. Conversely, low P concentrations in tile-drainage waters (< 0.03 mg L-1) and a moderate mean Mehlich(III) P/Al ratio of 8% were observed in the higher P sorbing soil group. Total P concentrations in drainage systems were significantly related to soil P status in surface soils. Grouping soils according to their P sorption capacities increased the power of prediction based on only one soil variable. However, accurate predictions in terms of drain P concentration can hardly be obtained unless large dataset and other factors related to field management practices and hydrology of the sites are also considered. Therefore, a better alternative to predict the risk of P leaching is to work in terms of risk classes and rely on a multiple factor index. Key words: Tile-drainage water, phosphorus, P transfer, P loss, degree of soil P saturation, phosphorus index

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Genetic variation of seed phosphorus concentration in winter oilseed rape and development of a NIRS calibration

Euphytica ◽

10.1007/s10681-021-02782-3 ◽

2021 ◽

Vol 217 (4) ◽

Author(s):

Jakob Eifler ◽

Jürgen Enno Wick ◽

Bernd Steingrobe ◽

Christian Möllers

Keyword(s):

Genetic Variation ◽

Field Experiments ◽

Seed Quality ◽

Rapeseed Meal ◽

Quality Analysis ◽

Phosphorus Concentration ◽

Genotypic Differences ◽

Organic P ◽

P Concentration ◽

Total P

AbstractPhytic acid is the major organic phosphorus storage compound in rapeseed. Following oil extraction, the defatted meal is used in feed mixtures for livestock. However, monogastric pigs and chickens can only poorly metabolize phytate. Hence, their excrements are rich in phosphorus (P), which when applied as manure may lead to eutrophication of surface waters. The aim of the present study was to analyze the genetic variation for total and organic P concentration (i.e. mainly phytate) in rapeseed and to compare the results with soybean. Two sets of rapeseed material were tested in field experiments in different environments with varying soil P levels and harvested seeds were used for seed quality analysis. Results revealed significant genotypic differences in total seed P concentration, which ranged from 0.47 to 0.94%. Depending on the experiment, the heritability for total P concentration ranged from 52 to 93%. The organic P portion of total P concentration was above 90% for current rapeseed hybrids. In both sets, there was a significant positive correlation between seed protein and P concentration. A NIRS calibration for total P concentration in intact seeds showed in cross validation a standard error of 0.05% and a coefficient of determination of R2 = 0.83. Total P concentration of soybean seeds and meal was between 0.55 and 0.65%, and around 1.1% for rapeseed meal. Rapeseed meal had a twofold higher ratio of total P to nitrogen concentration as compared to soybean which could be considered adverse when the meal is used for feeding livestock.

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Plant mechanisms to optimise access to soil phosphorus

Crop and Pasture Science ◽

10.1071/cp07125 ◽

2009 ◽

Vol 60 (2) ◽

pp. 124 ◽

Cited By ~ 223

Author(s):

Alan E. Richardson ◽

Peter J. Hocking ◽

Richard J. Simpson ◽

Timothy S. George

Keyword(s):

Plant Growth ◽

Mycorrhizal Fungi ◽

Specific Root Length ◽

Soluble Form ◽

P Availability ◽

Agricultural Systems ◽

Root Characteristics ◽

P Deficiency ◽

Soil P ◽

Total P

Phosphorus (P) is an important nutrient required for plant growth and its management in soil is critical to ensure sustainable and profitable agriculture that has minimal impact on the environment. Although soils may contain a large amount of total P, only a small proportion is immediately available to plants. Australian soils often have low availability of P for plant growth and P-based fertilisers are, therefore, commonly used to correct P deficiency and to maintain productivity. For many soils, the sustained use of P fertiliser has resulted in an accumulation of total P, a proportion of which is in forms that are poorly available to most plants. The efficiency with which different P fertilisers are used in agricultural systems depends on their capacity to supply P in a soluble form that is available for plant uptake (i.e. as orthophosphate anions). In addition to fertiliser source, the availability of P in soil is influenced to a large extent by physico-chemical and biological properties of the soil. Plant access to soil P is further affected by root characteristics (e.g. rate of growth, specific root length, and density and length of root hairs) and biochemical processes that occur at the soil–root interface. The ability of roots to effectively explore soil, the release of exudates (e.g. organic anions and phosphatases) from roots that influence soil P availability, and the association of roots with soil microorganisms such as mycorrhizal fungi are particularly important. These processes occur as a natural response of plants to P deficiency and, through better understanding, may provide opportunities for improving plant access to soil and fertiliser P in conventional and organic agricultural systems.

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Interpretation of a single-point P buffering index for adjusting critical levels of the Colwell soil P test

Soil Research ◽

10.1071/sr06056 ◽

2007 ◽

Vol 45 (1) ◽

pp. 55 ◽

Cited By ~ 70

Author(s):

P. W. Moody

Keyword(s):

Buffer Capacity ◽

Soil Phosphorus ◽

Single Point ◽

Maximum Yield ◽

P Value ◽

P Availability ◽

Soil P ◽

P Concentration ◽

Soil P Test ◽

Rate Of Increase

Soil phosphorus (P) buffer capacity is the change in the quantity of sorbed P required per unit change in solution P concentration. Because P availability to crops is mainly determined by solution P concentration, as P buffer capacity increases, so does the quantity of P required to maintain a solution P concentration that is adequate for crop demand. Bicarbonate-extractable P using the Colwell method is the most common soil P test used in Australia, and Colwell-P can be considered to estimate P quantity. Therefore, as P buffer capacity increases, the Colwell-P concentration required for maximum yield also increases. Data from several published and unpublished studies are used to derive relationships between the ‘critical’ Colwell-P value (Colwell-P at 90% maximum yield) and the single-point P buffer index (PBI) for annual medics, soybean, potato, wheat, and temperate pasture. The rate of increase in critical Colwell-P with increasing PBI increases in the order: temperate pasture < medics < wheat < potato. Indicative critical Colwell-P values are given for the 5 crops at each of the PBI categories used to describe soil P buffer capacity as it increases from extremely low to very high.

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Soil Phosphorus Speciation and Availability in Meadows and Forests in Alpine Lake Watersheds With Different Parent Materials

Frontiers in Forests and Global Change ◽

10.3389/ffgc.2020.604200 ◽

2021 ◽

Vol 3 ◽

Author(s):

Thomas Heron ◽

Daniel G. Strawn ◽

Mariana Dobre ◽

Barbara J. Cade-Menun ◽

Chinmay Deval ◽

...

Keyword(s):

Forest Soils ◽

Management Practices ◽

Lake Tahoe ◽

Parent Material ◽

P Availability ◽

Organic P ◽

Lake Tahoe Basin ◽

Parent Materials ◽

Tahoe Basin ◽

Total P

In the Lake Tahoe Basin in California and Nevada (USA), managing nutrient export from watersheds into streams and the lake is a significant challenge that needs to be addressed to improve water quality. Leaching and runoff of phosphorus (P) from soils is a major nutrient source to the lake, and P loading potential from different watersheds varies as a function of landscape and ecosystem properties, and how the watershed is managed. In this research, P availability and speciation in forest and meadow soils in the Lake Tahoe Basin were measured at two watersheds with different parent material types. Soils developed on andesitic parent materials had approximately twice as much total P compared to those developed on granitic parent materials. Regardless of parent material, organic P was 79–92% of the total P in the meadow soils, and only 13–47% in the forest soils. Most of the soil organic P consisted of monoester P compounds, but a significant amount, especially in meadow soils, was diester P compounds (up to 30% of total extracted P). Water extractable P (WEP) concentrations were ~10 times greater in the granitic forest soils compared to the andesitic forest soils, which had more poorly crystalline aluminosilicates and iron oxides that retain P and thus restrict WEP export. In the meadow soils, microbial biomass P was approximately seven times greater than the forest soils, which may be an important sink for P leached from upland forests. Results show that ecosystem and parent material are important attributes that control P speciation and availability in the Lake Tahoe Basin, and that organic P compounds are a major component of the soil P and are available for leaching from the soils. These factors can be used to develop accurate predictions of P availability and more precise forest management practices to reduce P export into Lake Tahoe.

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Effect of long-term phosphorus fertilization on soil phosphorus fractions .

Spanish Journal of Soil Science ◽

10.3232/sjss.2012.v2.n2.03 ◽

2014 ◽

Vol 2 ◽

Author(s):

Ester Crisitna Zamuner ◽

Andrea Beatriz Díez ◽

Liliana Inés Picone

Keyword(s):

Crop Production ◽

High Rate ◽

Phosphorus Fertilization ◽

Buenos Aires Province ◽

P Availability ◽

P Fertilization ◽

Soil P ◽

Total P ◽

Bray 1 ◽

Low Rate

A limitation to crop production in the southeast of the Buenos Aires province (Argentina) is the low phosphorus (P) availability. P fertilization is required for high yields. The objective of this work was to quantify the forms of soil P as affected by different P fertilization strategies after 8 years under wheat. The combination of high rate (H; 176 kg P ha-1), low rate (L; 88 kg P ha-1), single application (S; at the beginning of the experiment), and fractionated application (F; annual fertilization of 22 and 11 kg P ha-1) were evaluated. Soil total P, total inorganic P, total organic P, organic (Po) and inorganic (Pi) extractable with NaHCO3 and NaOH, were determined, plus available P (P-Bray 1). Fertilization did not change the total P or the total Po (344 and 412 mg P kg-1, respectively). Fertilized treatment, compared with a non-fertilized one, increased the concentration of Pi-NaHCO3 (14.49 and 7.62 mg P kg-1) and Pi-NaOH (47.13 and 28.37 mg P kg-1). The H rate increased the Pi extracted with NaHCO3 (13.16 mg P kg-1) and with NaOH (53.82 mg P kg-1) compared with the L rate (9.82 and 40.43 mg P kg-1, respectively). The FH rate increased the concentration of Pi-NaOH (59.55 mg P kg-1) compared to SH (48.10 mg P kg-1), while the low rate produced no changes in this fraction. In summary, when the amount of P added was fractioned and exceeded the quantity removed by crop, the excess was converted mainly to Pi-NaOH. A positive and significant correlation (r2 = 0.95; P < 0.001) between the sum of Pi-NaHCO3, Pi- NaOH and P-Bray 1 was established.

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Soil P in a forested seabird colony: inventories, parent material contributions, and N : P stoichiometry

Soil Research ◽

10.1071/sr05075 ◽

2005 ◽

Vol 43 (8) ◽

pp. 957 ◽

Cited By ~ 15

Author(s):

David J. Hawke

Keyword(s):

Peat Soil ◽

Drainage Water ◽

Parent Material ◽

Reference Element ◽

Soil System ◽

Soil C ◽

Soil P ◽

Seabird Colony ◽

Fisheries Waste ◽

Total P

Guano from breeding seabirds provides a large external source of nutrients to the soils of breeding colonies. However, little is known of guano P retention relative to N or the relative importance of guano and soil parent material as P sources. Soil profile N and P inventories (0–0.60 m, n = 4; 0–0.36 m, n = 1) and guano N and P concentrations were measured at a Westland petrel colony, and the parent material contributions of P were calculated using Ca, Al, Fe, Ti, and Zr as reference elements. Median inventories (0–0.60 m) were 1.49 kg N/m2 and 332 × 10–3 kg P/m2, the N result being similar to that from a seabird colony on peat soil where N retention was very low. Calculated parent material contributions were smallest (32–66% of soil P) when based on Ca and largest (47–102% of soil P) when based on Zr. Contributions were similar for Al, Fe, and Ti; Al (41–87% soil P) was selected for subsequent calculations. Regardless of the reference element, parent material therefore contributed a large part of soil P. Phosphorus in excess of parent material supply (Pexcess) was significantly correlated with soil C, implying that guano P is held primarily in organic form. The median soil N : P molar ratios were 9.6 : 1 based on total P and 11.2 : 1 based on Pexcess, compared with ratios for Westland petrel guano of 4.1 : 1 (when birds were consuming fisheries waste) and 16.4 : 1 (when fisheries waste was replaced by fish). The similarity between soil and guano N : P ratios implies that both N and P are lost from soil at similar rates, although volatilisation of N would enrich soil drainage water in P. Calculations using guano deposition rates from the literature yielded P residence times of 4–15 years (Pexcess) and 11–41 years (total P), consistent with a highly dynamic soil system.

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Soil phosphorus supply affects nodulation and N:P ratio in 11 perennial legume seedlings

Crop and Pasture Science ◽

10.1071/cp11229 ◽

2011 ◽

Vol 62 (11) ◽

pp. 992 ◽

Cited By ~ 10

Author(s):

Jiayin Pang ◽

Mark Tibbett ◽

Matthew D. Denton ◽

Hans Lambers ◽

Kadambot H. M. Siddique ◽

...

Keyword(s):

N Uptake ◽

Dry Weight ◽

Good Growth ◽

P Availability ◽

Soil P ◽

Pasture Legumes ◽

P Concentration ◽

N Concentration ◽

P Supply ◽

N Status

Developing new perennial pasture legumes for low-P soils is a priority for Australian Mediterranean agro-ecosystems, where soil P availability is naturally low. As legumes tend to require higher P inputs than non-legumes, the ability of these plants to fix N2 under varying soil P levels must be determined. Therefore, the objective of this study was to investigate the influence of soil P supply on plant N status and nodule formation in 11 perennial legumes, including some novel pasture species. We investigated the effect of applying soil P, ranging from 0 to 384 μg P/g dry soil, on plant N status and nodulation in a glasshouse. Without exogenous P supply, shoot N concentration and N : P ratio were higher than at 6 μg P/g soil. Shoot N concentration and N : P ratio then changed little with further increase in P supply. There was a close positive correlation between the number of nodules and shoot P concentration in 7 of the 11 species. Total nodule dry weight and the percentage of plant dry weight that consisted of nodules increased when P supply increased from 6 to 48 μg P/g. Without exogenous P addition, N : P ratios partitioned into a two-group distribution, with species having a N : P ratio of either >70 or <50 g/g. We suggest that plants with a high N : P ratio may take up N from the soil constitutively, while those with a low N : P ratio may regulate their N uptake in relation to internal P concentration. The flexibility of the novel pasture legumes in this study to adjust their leaf N concentrations under different levels of soil P supplements other published evidence of good growth and high P uptake and P-use efficiency under low soil P supply and suggests their potential as pasture plants in low-P soils in Australian Mediterranean agro-ecosystems warrants further attention.

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Relationships of phosphorus concentration in reproductive organs with soil phosphorus availability for tropical rain-forest trees on Mount Kinabalu, Borneo

Journal of Tropical Ecology ◽

10.1017/s0266467418000329 ◽

2018 ◽

Vol 34 (6) ◽

pp. 351-363

Author(s):

Yuki Tsujii ◽

Kanehiro Kitayama

Keyword(s):

Reproductive Organs ◽

Reproductive Organ ◽

Phosphorus Concentration ◽

P Availability ◽

P Deficiency ◽

P Use Efficiency ◽

Tree Community ◽

P Concentration ◽

Mount Kinabalu ◽

Use Efficiency

Abstract:Bornean rain forests on phosphorus (P)-poor soils exhibit a high P-use efficiency in the production of reproductive organs (i.e. the inverse of P concentration in reproductive-organ litter). The mechanism underpinning this high P-use efficiency is not known, but is hypothesized to result from dilution of P in a given type of reproductive organ and/or a shift of the community composition of flower/fruit types with decreasing P availability. These hypotheses were tested using eight forests with different soil P availabilities on Mount Kinabalu, Borneo. Mean P concentration per forest by genus in inflorescences was significantly positively correlated with P availability, while that in seeds or pericarps was not significantly correlated. This trend was consistent across 21 genera that we analysed, suggesting that P concentration in seeds is maintained in exchange with the dilution of P in inflorescences. The composition of fruit types in tree community was estimated based on the relative abundances of genera in each forest. The relative abundance of capsulate species, which required less P in pericarps, tended to increase in tree community with decreasing P availability. Therefore, both mechanisms were involved in P-use efficiency. This work provides an insight into the reproductive adaptation of trees to P deficiency.

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