Phosphorus Speciation in Long-Term Drained and Rewetted Peatlands of Northern Germany

Previous studies, conducted at the inception of rewetting degraded peatlands, reported that rewetting increased phosphorus (P) mobilization but long-term effects of rewetting on the soil P status are unknown. The objectives of this study were to (i) characterize P in the surface and subsurface horizons of long-term drained and rewetted percolation mires, forest, and coastal peatlands and (ii) examine the influence of drainage and rewetting on P speciation and distributions using wet-chemical and advanced spectroscopic analyses. The total P was significantly (p < 0.05) different at the surface horizons. The total concentration of P ranged from 1022 to 2320 mg kg−1 in the surface horizons and decreased by a factor of two to five to the deepest horizons. Results of the chemical, solution 31P nuclear magnetic resonance (NMR), and P K-edge X-ray absorption near-edge structure (XANES) indicated that the major proportions of total P were organic P (Po). In the same peatland types, the relative proportions of Po and stable P fractions were lower in the drained than in the rewetted peatland. The results indicate that long-term rewetting not only locks P in organic matter but also transforms labile P to stable P fractions at the surface horizons of the different peatland types.

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Long-Term Mineral Fertilization Improved the Grain Yield and Phosphorus Use Efficiency by Changing Soil P Fractions in Ferralic Cambisol

Agronomy ◽

10.3390/agronomy9120784 ◽

2019 ◽

Vol 9 (12) ◽

pp. 784 ◽

Cited By ~ 4

Author(s):

Waqas Ahmed ◽

Kailou Liu ◽

Muhammad Qaswar ◽

Jing Huang ◽

Qinghai Huang ◽

...

Keyword(s):

Grain Yield ◽

Paddy Soils ◽

P Fractions ◽

Mineral Fertilization ◽

Mineral N ◽

Soil P ◽

Soil P Fractions ◽

Use Efficiency ◽

Labile P

Elevated mineral fertilization may change the composition and increase the availability of soil phosphorus (P) in subtropical paddy soils and thus affect long-term plant growth. However, an understanding of the response of soil P fractions to long-term nitrogen, phosphorus and potassium (NPK) additions remains elusive. This study aimed to explore the responses of soil P-fractions and their mobility to different long-term chemical fertilization rates under a double rice cropping system. The rates of nitrogen (N), phosphorus (P), and potassium (K) in the low NPK treatment (LNPK) were 90, 45, and 75 kg ha−1 year−1, respectively, and in the high NPK treatment (HNPK), they were 180, 90, and 150 kg ha−1 year−1, respectively. The results showed that the concentrations of soil organic matter (SOM), total P, Olsen P, total N, and mineral N were remarkably increased under HNPK by 17.46%, 162.66%, 721.16%, 104.42%, and 414.46%, respectively, compared with those under control (CT). Compared to the CT P fractions, HNPK increased the labile P fractions (i.e., NaHCO3-Pi and NaHCO3-Po) by 322.25% and 83.53% and the moderately labile P fractions (i.e., NaOH-Pi, NaOH-Po and HCl. dil. Pi) by 163.54%, 183.78%, and 3167.25% respectively, while the non-labile P was decreased by the HNPK addition. P uptake and grain yield were increased by LNPK and HNPK by 10.02% and 35.20%, respectively, compared with CT. P use efficiency indices were also higher under HNPK than under LNPK. There was a strong positive relationship between grain yield and P use efficiency (R2 = 0.97). A redundancy analysis (RDA) showed a strong correlation between soil chemical properties and the labile and moderately labile P pools. Structural equation modeling (SEM) revealed that SOM, mineral N, and available P strongly control the labile P pool. In conclusion, NPK additions under the paddy soils significantly influences the soil P fractions. The soil P dynamics and the mechanisms governing the interactions between plants and soil nutrients are clearly explained in this study.

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The influences of historic lake trophy and mixing regime changes on long-term phosphorus fractions retention in sediments of deep, eutrophic lakes: a case study from Lake Burgäschi, Switzerland

10.5194/bg-2019-389 ◽

2019 ◽

Cited By ~ 1

Author(s):

Luyao Tu ◽

Paul Zander ◽

Sönke Szidat ◽

Ronald Lloren ◽

Martin Grosjean

Keyword(s):

Binding Capacity ◽

Redox Conditions ◽

P Availability ◽

P Fractions ◽

Eutrophic Lakes ◽

Anoxic Hypolimnion ◽

P Fraction ◽

Labile P ◽

Total P

Abstract. Hypolimnetic anoxia in eutrophic lakes can delay lake recovery to lower trophic states via the release of sediment phosphorus (P) to surface waters on short time scales. However, the effects of hypolimnetic redox conditions and eutrophication on long-term sediment P-fraction retention are not clear yet. In this study, we investigated the sediment profiles since the early 1900s from Lake Burgäschi, a deep, eutrophic lake on the Swiss Plateau. The changes of sediment P-fraction retention were assessed with respect to lake trophic evolution (sedimentary green-pigments proxy), hypolimnetic oxygenation regime (Fe / Mn ratio proxy), sediment geochemical characteristics, and lake restoration history. Results showed that long-term retention of total P and labile P-fractions in sediments was predominantly affected by autochthonous Fe and Mn preserved in anoxic sediments, which were controlled by past hypolimnetic redox conditions. By contrast, refractory HCl-P (Ca-P) fraction retention largely resulted from authigenic CaCO3-P precipitation and increased with higher eutrophic levels. The retention of total P and labile P fractions was considerably reduced in surface sediments from 1977–2017 when Lake Burgäschi had the highest eutrophic levels and a persistent anoxic hypolimnion. We attributed the phenomenon to reduced sediment P-binding capacity (Mn and Fe oxyhydroxides) under the eutrophication-induced anoxic hypolimnion and decreased water-P concentrations due to hypolimnetic withdrawal. Our study implies that in seasonally stratified deep lakes like Lake Burgäschi, hypolimnetic withdrawal of P-enriched water can effectively reduce P retention in sediments and potentials of sediment-P release (seen from low P availability after 1977). However, the restoration has not improved lake trophic state, similarly to the findings from lake limnological survey.

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Phosphorus Forms and Associated Properties along an Urban–Rural Gradient in Southern China

Water ◽

10.3390/w11122504 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2504 ◽

Cited By ~ 1

Author(s):

Guobing Qin ◽

Jianfu Wu ◽

Xiaomei Zheng ◽

Rongwei Zhou ◽

Zongqiang Wei

Keyword(s):

Urban Soil ◽

Urban Soils ◽

Southern China ◽

P Fractions ◽

Environmental Implications ◽

Residual P ◽

Soil P ◽

Urban Rural ◽

Labile P ◽

Total P

Urbanization is widely assumed to degrade soil ecosystem services, but the changes in the urban soil phosphorus (P) status due to urbanization and the associated environmental implications have rarely been studied. The objective of this study was to investigate the P forms and associated soil properties in urban soils. Thirty sites were selected along an urban–rural gradient in Nanchang, China, to examine the effects of urbanization on soil P fractions. Residual P and NaOH-extractable P (NaOH-Pi and NaOHPo) were the major P forms in the 0–30 cm of urban soils, comprising on average 37% and 43% of the total P pool, respectively, similar to the suburban and rural soils. Compared with non-urban soils, urban soil had higher contents of total P and P fractions (i.e., PH2O, PKCl, NaOH-Pi, PHCl, and residual P), as well as higher contents of related soil P-retentive properties, especially soil pH and Mehlich 3-extractable Ca and Mg. Phosphorus enrichment in the urban soils may become a source of aquatic pollution because the soil labile P content (the sum of PH2O and PKCl) was positively related to total P, PHCl, NaOH-Pi, and residual P, which implied that the labile P can be replenished by these P pools. This study increased the understanding of P stabilization characteristics (e.g., the specific P forms) of urban soils and has further implications for urban environmental management.

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Long-term effects of liquid hog manure on the phosphorus status of a silt loam cropped to corn

Canadian Journal of Soil Science ◽

10.4141/s02-017 ◽

2003 ◽

Vol 83 (5) ◽

pp. 589-600 ◽

Cited By ~ 5

Author(s):

I. Royer ◽

R. R. Simard ◽

G. M. Barnett ◽

D. Cluis ◽

D. A. Angers

Keyword(s):

Water Contamination ◽

Water Soluble ◽

Silt Loam ◽

Long Term Effects ◽

Soil P ◽

Total Soil ◽

P Content ◽

Hog Manure ◽

Labile P

Repeated application of animal manure or mineral P fertilizer can significantly increase soil P content and enhance the risk of water contamination. The objectives of this study were to evaluate the long-term (8 yr) effect of liquid hog manure (LHM) applied at high rates and its timing of application on the soil P status and on the risk index of water contamination by P. Spring (S), fall (F), or spring + fall (SF) applications of LHM on a silt loam (Humo Ferric Podzol) were compared to recommended application rates of mineral fertilizer (MF) in a continuous corn (Zea mays L.) system. Total P applied ranged from 7 to 34 kg P ha-1 yr-1 in the MF treatment and from 106 to 150 kg P haP ha-1 yr-1 in the LHM treatments. Soil samples were collected to 1.0-m depth after one, six and eight annual applications. Applying high rates of LHM for 8 consecutive years resulted in a significant (P ≤ 0.10) enrichment in total soil P content relative to MF at the 0- to 20-cm soil depth. The effects of LHM on labile P forms (water soluble P, Pw and Mehlich-III extractable P, M3P) were also restricted to the 0- to 20-cm depth with values as high as 11 mg kg-1 for Pw and 241 mg kg-1 for M3P in the LHM plots. The degree of soil P saturation, evaluated as Pox/(Alox+Feox), increased to 15% in the 0- to 20-cm depth after 6 to 8 yr of LHM application. Saturation values of 12 to 15% were also found at the 80- to 100-cm depth in some LHM plots. The P index rating was always medium (109 to 216) in soil receiving MF but was high (217 to 432) after 6 to 8 yr of heavy LHM applications, which indicates a high potential risk of soil P transfer to surface water. The results of this study showed that timing of application had little influence on long-term soil P status. Overall, applying LHM at high rates greatly increased total soil P, the degree of soil P saturation, and the labile P forms in the surface horizons but had little effects below 20 cm. Key words: Hog manure, soil P, long-term effects, labile P, P saturation

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The influences of historic lake trophy and mixing regime changes on long-term phosphorus fraction retention in sediments of deep eutrophic lakes: a case study from Lake Burgäschi, Switzerland

Biogeosciences ◽

10.5194/bg-17-2715-2020 ◽

2020 ◽

Vol 17 (10) ◽

pp. 2715-2729 ◽

Cited By ~ 2

Author(s):

Luyao Tu ◽

Paul Zander ◽

Sönke Szidat ◽

Ronald Lloren ◽

Martin Grosjean

Keyword(s):

Trophic State ◽

Surface Sediments ◽

P Fractions ◽

Deep Lakes ◽

Eutrophic Lakes ◽

P Fraction ◽

Labile P ◽

Total P ◽

P Retention

Abstract. Hypolimnetic anoxia in eutrophic lakes can delay lake recovery to lower trophic states via the release of sediment phosphorus (P) to surface waters on short timescales in shallow lakes. However, the long-term effects of hypolimnetic redox conditions and trophic state on sedimentary P fraction retention in deep lakes are not clear yet. Hypolimnetic withdrawal of P-rich water is predicted to diminish sedimentary P and seasonal P recycling from the lake hypolimnion. Nevertheless, there is a lack of evidence from well-dated sediment cores, in particular from deep lakes, about the long-term impact of hypolimnetic withdrawal on sedimentary P retention. In this study, long-term sedimentary P fraction data since the early 1900s from Lake Burgäschi provide information on benthic P retention under the influence of increasing lake primary productivity (sedimentary green-pigment proxy), variable hypolimnion oxygenation regimes (Fe∕Mn ratio proxy), and hypolimnetic withdrawal since 1977. Results show that before hypolimnetic withdrawal (during the early 1900s to 1977), the redox-sensitive Fe∕Mn-P fraction comprised ∼50 % of total P (TP) in the sediment profile. Meanwhile, long-term retention of total P and labile P fractions in sediments was predominantly affected by past hypolimnetic redox conditions, and P retention increased in sedimentary Fe- and Mn-enriched layers when the sediment-overlaying water was seasonally oxic. However, from 1977 to 2017, due to eutrophication-induced persistent anoxic conditions in the hypolimnion and to hypolimnetic water withdrawal increasing the P export out of the lake, net burial rates of total and labile P fractions decreased considerably in surface sediments. By contrast, refractory Ca–P fraction retention was primarily related to lake primary production. Due to lake restoration since 1977, the Ca–P fraction became the primary P fraction in sediments (representing ∼39 % of total P), indicating a lower P bioavailability of surface sediments. Our study implies that in seasonally stratified eutrophic deep lakes (like Lake Burgäschi), hypolimnetic withdrawal can effectively reduce P retention in sediments and potential for sediment P release (internal P loads). However, after more than 40 years of hypolimnetic syphoning, the lake trophic state has not improved nor has lake productivity decreased. Furthermore, this restoration has not enhanced water column mixing and oxygenation in hypolimnetic waters. The findings of this study are relevant regarding the management of deep eutrophic lakes with mixing regimes typical for temperate zones.

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Effect of biochar addition on legacy phosphorus availability in long-term cultivated arid soil

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-021-00249-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Khaled D. Alotaibi ◽

Melissa Arcand ◽

Noura Ziadi

Keyword(s):

Chicken Manure ◽

Chemical Extraction ◽

P Availability ◽

P Fractions ◽

Arid Soil ◽

Soil P ◽

Sequential Chemical Extraction ◽

P Content ◽

Labile P

Abstract Background Continuous application of phosphorus (P) nutrient in association with its low recovery results in large amounts of P being accumulated in soil in different forms. Use of biochar can be a possible means to mobilize soil legacy P and increase its bioavailability. Therefore, the aim of this study was to identify the potential impact of a range of biochar types on P fractions in a long-term cultivated arid soil with high legacy P content. Methodology The soil was treated with biochar produced from four feedstock sources (BFS): sewage sludge (SSB), olive mill pomace (OPB), chicken manure (CMB), and date palm residues (DRB) pyrolyzed at 300, 500, or 700 °C in addition to an untreated control. The soil biochar mixture was incubated for 1 month followed by soil P fractionations using sequential chemical extraction to separate soil P into: labile (Resin-Pi, NaHCO3-Pi, NaHCO3-Po), moderately labile (NaOH-Pi, NaOH-Po), and non-labile (HCl-Pi and Residual-P) pools. Results Biochar addition clearly influenced most of the soil P fractions; however, the extent of this effect greatly varied depending on BFS and pyrolysis temperature (PT). The most evident biochar impact was observed with labile P pool, with the greatest increase being observed in NaHCO3-Pi fraction in most biochar treatments. Irrespective of PT, SSB and CMB were the most effective biochar type in increasing labile inorganic P; the SSB and CMB increased Resin-Pi by 77 and 206% and NaHCO3-Pi by 200 and 188%, respectively. In contrast, DRB made no changes in any P fraction. Differences in effects of biochar types on labile P is presumably related to the higher content of P in biowaste-based biochar compared to plant-based biochar which have much lower P content. The SSB, CMB, and OPB produced at low temperature reduced HCl-Pi content, indicating that these biochars may have stimulated organic matter decomposition and thereby dissolution of non-labile Ca-associated P to labile P forms. Conclusion Overall, biochar addition appeared to be an effective approach in enhancing legacy P availability in arid soil. However, further studies are necessary to verify these findings in the presence of plant and for a longer period. Graphic abstract

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Changes in phosphorus fractions at various soil depths following long-term P fertiliser application on a Black Vertosol from south-eastern Queensland

Soil Research ◽

10.1071/sr07069 ◽

2007 ◽

Vol 45 (7) ◽

pp. 524 ◽

Cited By ~ 49

Author(s):

X. Wang ◽

D. W. Lester ◽

C. N. Guppy ◽

P. V. Lockwood ◽

C. Tang

Keyword(s):

Surface Soil ◽

P Fractions ◽

Inorganic P ◽

Residual P ◽

Soil P ◽

P Pools ◽

Fertiliser Application ◽

P Addition ◽

Total P

Long-term removal of grain P and soil test data suggested that the Colwell phosphorus (P) extraction from the surface 0.10 m of a Black Vertosol from south-eastern Queensland was a poor indicator of run-down of soil P pools. We proposed that plants were also accessing P from layers below 0.10 m or from surface soil P pools not extracted by the Colwell extraction. Both topsoil and subsoil samples in 1994 and 2003 were collected from nil and 20 kg P/ha per crop treatments in a long-term N × P field experiment established in 1985 for detailed P fractionation. An uncropped reference soil was also taken in 2003 from an adjacent area. The long-term effect of the field treatments on soil P fractions was evaluated by comparing the reference site, which was assumed to represent the original soil condition, to the 2003 samples. Without addition of P fertiliser, 55%, 35%, and 10% of total P removal were from 0 to 0.10, 0.10 to 0.30, and 0.30 to 0.60 m, respectively, compared with the uncropped reference soil. Labile fractions comprising resin, bicarbonate, and hydroxide pools in the top 0.10 m decreased by approximately 60% and accounted for 15% of the total P decrease from 0 to 0.60 m depth. Acid and residual-P fractions decreased by 50% and 20%, respectively, and accounted for ~20% and 15% of the total P decrease. In contrast, P addition at 20 kg P/ha per crop over 18 crops doubled the resin and bicarbonate inorganic P (NaHCO3-Pi) pools in the surface 0.10 m. Hydroxide (NaOH-Pi) and acid extracted inorganic P increased by 25% and 10%, respectively, while the residual-P pool decreased by about 15%. Below 0.10 m, very little P was removed by the first 3 extractants. Most of the P was present in the acid and residual fractions irrespective of fertiliser application. The acid and residual-P dropped by 30% and 12%, respectively, at 0.10–0.30 m and 12% and 8% at 0.30–0.60 m. When comparing the experimental soil samples in 2003 with those in 1994, similar trends were observed in the changes of each soil P fraction. In the surface 0.10 m, acid and residual-P pools decreased greatly and explained almost all of the total P decrease in the surface soil without P input. With P addition, labile pools acted as the main sink for P. The acid pool increased by 7%, while the residual-P showed a decrease in the topsoil. Total P level was elevated noticeably in this soil layer. However, at 0.10–0.30 m depth, acid and residual pools were the dominant fractions and decreased significantly irrespective of P fertiliser addition. Below 0.30 m, no significant changes were detected for each fraction and total P. The results suggest that crops had accessed significant amounts of P at 0.10–0.30 m depth irrespective of P fertiliser application, and that subsoil sampling (0.10–0.30 m) should be considered in order to improve the monitoring of soil P status. However, choice of appropriate extractants for monitoring subsoil P reserves is yet to be undertaken.

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Microscale Heterogeneous Distribution and Speciation of Phosphorus in Soils Amended with Mineral Fertilizer and Cattle Manure Compost

Minerals ◽

10.3390/min11020121 ◽

2021 ◽

Vol 11 (2) ◽

pp. 121

Author(s):

Noriko Yamaguchi ◽

Toshiaki Ohkura ◽

Atsuko Hikono ◽

Yohey Hashimoto ◽

Aomi Suda ◽

...

Keyword(s):

Hot Spots ◽

Mineral Fertilizer ◽

Chemical Extraction ◽

Heterogeneous Distribution ◽

Edge Structure ◽

Soil P ◽

Macro Scale ◽

Cattle Manure Compost ◽

High Degree

Global concerns for the sustainability of agriculture have emphasized the need to reduce the use of mineral fertilizer. Although phosphorus (P) is accumulated in farmland soils due to the long-term application of fertilizer, most soil P is not readily available to plants. The chemical speciation of P in soils, which comprise heterogeneous microenvironments, cannot be evaluated with a high degree of specificity using only macroscopic analyses. In this study, we investigated the distribution and speciation of P accumulated in soils by using both macro- and microscopic techniques including chemical extraction, solution and solid-state 31P NMR, bulk- and micro- P K-edge X-ray absorption near edge structure (XANES), and electron probe microanalysis (EPMA). Soil samples were collected from a field in which cabbage was cultivated under three amendment treatments: i) mineral fertilizer (NPK), ii) mineral fertilizer and compost (NPK + compost), and iii) mineral fertilizer plus compost but without nitrogen fertilizer (PK + compost). Macro-scale analyses suggested that accumulated P was predominantly inorganic P and associated with Al-bearing minerals. The repeated application of compost to the soils increased the proportion of P associated with Ca which accounted for 17% in the NPK + compost plot and 40% in the PK + compost plot. At the microscale, hot spots of P were heterogeneously distributed, and P was associated with Fe and Ca in hot spots of the NPK + compost (pH 6) and PK + compost (pH 7) treated samples, respectively. Our results indicate that application of compost contributed to creating diverse microenvironments hosting P in these soils.

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Distribution of phosphorus fractions of different plant availability in German forest soils and their relationship to common soil properties and foliar P concentrations

10.5194/soil-2018-40 ◽

2018 ◽

Author(s):

Jörg Niederberger ◽

Martin Kohler ◽

Jürgen Bauhus

Keyword(s):

Soil Properties ◽

Forest Soil ◽

Soil Survey ◽

Soil Conditions ◽

Organic Carbon Content ◽

P Fractions ◽

P Pools ◽

P Content ◽

Labile P ◽

Total P

Abstract. Repeated, grid-based forest soil inventories such as the nationwide German forest soil survey (GFSI) aim, among other things, at detecting changes in soil properties and plant nutrition. In these types of inventories, the only information on soil phosphorus (P) is commonly the total P content. However, total P content in mineral soils of forests is usually not a meaningful variable to predict the availability of P to trees. Here we tested a modified sequential P extraction ac-cording to Hedley to determine the distribution of different plant available P fractions in soil samples (0–5 and 10–30 cm depth) from 146 GFSI sites, capturing a wide variety of soil conditions. In addition, we analyzed relationships between these P fractions and common soil proper-ties such as pH, texture, and organic Carbon content (SOC). Total P content among our samples ranged from approximately 60 up to 2800 mg kg−1. The labile, moderately labile, and stable P fractions contributed to 27 %, 51 % and 22 % of total P content, respectively, at 0–5 cm depth. At 10–30 cm depth, the labile P fractions decreased to 15 %, whereas the stable P fractions in-creased to 30 %. These changes with depth were accompanied by a decrease in the organic P fractions. High P contents were related with high pH-values. Whereas the labile P pool increased with decreasing pH in absolute and relative terms, the stable P pool decreased in absolute and relative terms. Increasing SOC in soils led to significant increases in all P pools and in total P. In sandy soils, the P content across all fractions was lower than in other soil texture types. Multiple linear regressions indicated that P pools and P fractions were moderately well related to soil properties (r2 mostly above 0.5), and sand content of soils had the strongest influence. Foliage P concentrations in Pinus sylvestris were reasonably well explained by the labile and moderately labile P pool (r

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