Long-term nutrient inputs shift soil microbial functional profiles of phosphorus cycling in diverse agroecosystems

AbstractMicroorganisms play an important role in soil phosphorus (P) cycling and regulation of P availability in agroecosystems. However, the responses of the functional and ecological traits of P-transformation microorganisms to long-term nutrient inputs are largely unknown. This study used metagenomics to investigate changes in the relative abundance of microbial P-transformation genes at four long-term experimental sites that received various inputs of N and P nutrients (up to 39 years). Long-term P input increased microbial P immobilization by decreasing the relative abundance of the P-starvation response gene (phoR) and increasing that of the low-affinity inorganic phosphate transporter gene (pit). This contrasts with previous findings that low-P conditions facilitate P immobilization in culturable microorganisms in short-term studies. In comparison, long-term nitrogen (N) input significantly decreased soil pH, and consequently decreased the relative abundances of total microbial P-solubilizing genes and the abundances of Actinobacteria, Gammaproteobacteria, and Alphaproteobacteria containing genes coding for alkaline phosphatase, and weakened the connection of relevant key genes. This challenges the concept that microbial P-solubilization capacity is mainly regulated by N:P stoichiometry. It is concluded that long-term N inputs decreased microbial P-solubilizing and mineralizing capacity while P inputs favored microbial immobilization via altering the microbial functional profiles, providing a novel insight into the regulation of P cycling in sustainable agroecosystems from a microbial perspective.

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Soil phosphorus bioavailability as influenced by long-term management and applied phosphorus source

Canadian Journal of Soil Science ◽

10.1139/cjss-2018-0075 ◽

2019 ◽

Vol 99 (3) ◽

pp. 292-304

Author(s):

Tandra D. Fraser ◽

Derek H. Lynch ◽

Ivan P. O’Halloran ◽

R. Paul Voroney ◽

Martin H. Entz ◽

...

Keyword(s):

Management Practices ◽

Soil Phosphorus ◽

P Uptake ◽

Italian Ryegrass ◽

P Availability ◽

P Fractionation ◽

Soil P ◽

Plant P Uptake ◽

Term Management

Soil phosphorus (P) availability may be impacted by management practices, thereby affecting plant P uptake and plant response to P amendments. The aim of this study was to determine the effects of long-term management on soil P pools and to assess the response of P bioavailability, plant growth, and P uptake to mineral versus manure P treatments. Soils were collected from plots under organic (ORG), organic with composted manure (ORG + M), conventional (CONV), and restored prairie (PRA) management. Italian ryegrass (Lolium multiflorum L.) seedlings were grown in the greenhouse for 106 d in soils amended with various rates of manure or mineral P. The ORG soil had lower concentrations of labile P (resin-P and NaHCO3-P) compared with the CONV and PRA soils, as determined by sequential P fractionation prior to planting. Ryegrass biomass (root + shoot) and shoot P uptake from soils receiving no P were significantly lower for the ORG than all other management systems. Although apparent P use efficiency of the whole plant was increased by low P rate in the ORG management system, the source of applied P, manure > mineral, only influenced Olsen test P.

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Influence of long-term irrigation on the distribution and availability of soil phosphorus under permanent pasture

Soil Research ◽

10.1071/sr05065 ◽

2006 ◽

Vol 44 (2) ◽

pp. 127 ◽

Cited By ~ 13

Author(s):

L. M. Condron ◽

S. Sinaj ◽

R. W. McDowell ◽

J. Dudler-Guela ◽

J. T. Scott ◽

...

Keyword(s):

Soil Phosphorus ◽

Soil Layer ◽

P Availability ◽

Organic P ◽

Retention Capacity ◽

Pasture Production ◽

Inorganic P ◽

Permanent Pasture ◽

P Movement

This study examined the influence of irrigation on soil phosphorus (P) distribution and availability under permanent pasture in New Zealand. Soil samples (0–0.075, 0.075–0.15, 0.15–0.25 m) were taken from a long-term field experiment, which included a dryland and 2 irrigation treatments (irrigated at 10% and 20% soil moisture) that had received 25 kg P/ha annually as superphosphate for 52 years. Corresponding data for soil from an adjacent ‘wilderness’ site that had not been used for agriculture for 54 years were included for comparison. Analyses included total P, organic P, and inorganic P; isotopic exchange kinetics (IEK) was used to determine soil inorganic P pools of differing plant availability. Concentrations of total and inorganic P were greater in soil taken from the dryland treatment than the irrigated treatments at all depths. This was attributed to a combination of decreased pasture growth and P transfer in drainage and off-farm produce. Concentrations of organic P were greater in the irrigated treatments (e.g. 0–0.075 m: 672–709 mg P/kg) than in the dryland treatment (e.g. 0–0.075 m: 574 mg P/kg) as a consequence of increased pasture production and soil biological activity. Inorganic P availability (Cp and E1min) was also greater in the dryland treatment than the irrigated treatments. Furthermore, concentrations of inorganic P in the recalcitrant IEK pool (E>3m = E3m–1y + E>1y) in the 0–0.075 m soil from the dryland treatment (479 mg P/kg) were significantly greater than the 10% irrigated (346 mg P/kg) and 20% irrigated (159 mg P/kg) treatments, which was mainly attributed to physico-chemical reactions that decreased the exchangeability of accumulated inorganic P with time. Despite increased P retention capacity at depth (R/r1, 0.15–0.25 m: dryland 6.6, 10% irrigated 10.2, 20% irrigated 12.8), concentrations of total inorganic P in the 0.15–0.25 m soil layer were lower under irrigation (195–266 mg P/kg) than dryland (354 mg P/kg), which indicated that long-term flood irrigation increased P transfer by leaching. The findings of this study revealed that while irrigation improved the utilisation of applied fertiliser P it also resulted in increased P movement to depth in the soil profile.

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Four soil phosphorus (P) tests evaluated by plant P uptake and P balancing in the Ultuna long-term field experiment

Plant Soil and Environment ◽

10.17221/313/2018-pse ◽

2018 ◽

Vol 64 (No. 9) ◽

pp. 441-447 ◽

Cited By ~ 1

Author(s):

Jarosch Klaus A ◽

Santner Jakob ◽

Parvage Mohammed Masud ◽

Gerzabek Martin Hubert ◽

Zehetner Franz ◽

...

Keyword(s):

Soil Phosphorus ◽

P Uptake ◽

P Availability ◽

Soil P ◽

Extractable P ◽

Plant P Uptake ◽

Soil P Tests ◽

Water Extractable ◽

Term Field

Soil phosphorus (P) availability was assessed with four different soil P tests on seven soils of the Ultuna long-term field experiment (Sweden). These four soil P tests were (1) P-H2O (water extractable P); (2) P-H2OC10 (water extractable P upon 10 consecutive extractions); (3) P-AL (ammonium lactate extractable P) and (4) P-CDGT (P desorbable using diffusive gradients in thin films). The suitability of these soil P tests to predict P availability was assessed by correlation with plant P uptake (mean of preceding 11 years) and soil P balancing (input vs. output on plot level for a period of 54 years). The ability to predict these parameters was in the order P-H2OC10 > P-CDGT > P-H2O > P-AL. Thus, methods considering the P-resupply from the soil solid phase to soil solution performed clearly better than equilibrium-based extractions. Our findings suggest that the P-AL test, commonly used for P-fertilizer recommendations in Sweden, could not predict plant P uptake and the soil P balance in a satisfying way in the analysed soils.

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Soil phosphorus dynamics during 17 years of continuous cultivation: A method to estimate long-term P availability

Geoderma ◽

10.1016/s0016-7061(97)00011-6 ◽

1997 ◽

Vol 78 (1-2) ◽

pp. 59-70 ◽

Cited By ~ 28

Author(s):

J.P Schmidt ◽

S.W Buol ◽

E.J Kamprath

Keyword(s):

Soil Phosphorus ◽

Continuous Cultivation ◽

P Availability ◽

Phosphorus Dynamics

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Effects of Rotations With Legume on Soil Functional Microbial Communities Involved in Phosphorus Transformation

Frontiers in Microbiology ◽

10.3389/fmicb.2021.661100 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hui Yu ◽

Fenghua Wang ◽

Minmin Shao ◽

Ling Huang ◽

Yangyang Xie ◽

...

Keyword(s):

Microbial Communities ◽

Soil Microbial Communities ◽

Soil Microbial ◽

P Cycling ◽

P Transformation ◽

Microbial P ◽

The Impact ◽

Metagenomic Approach ◽

Insight Into ◽

Phosphorus Transformation

Including legumes in the cereal cropping could improve the crop yield and the uptake of nitrogen (N) and phosphorus (P) of subsequent cereals. The effects of legume-cereal crop rotations on the soil microbial community have been studied in recent years, the impact on soil functional genes especially involved in P cycling is raising great concerns. The metagenomic approach was used to investigate the impacts of crop rotation managements of soybean-wheat (SW) and maize-wheat (MW) lasting 2 and 7years on soil microbial communities and genes involved in P transformation in a field experiment. Results indicated that SW rotation increased the relative abundances of Firmicutes and Bacteroidetes, reduced Actinobacteria, Verrucomicrobia, and Chloroflexi compared to MW rotation. gcd, phoR, phoD, and ppx predominated in genes involved in P transformation in both rotations. Genes of gcd, ppa, and ugpABCE showed higher abundances in SW rotation than in MW rotation, whereas gadAC and pstS showed less abundances. Proteobacteria, Acidobacteria, and Gemmatimonadetes played predominant roles in microbial P cycling. Our study provides a novel insight into crop P, which requires strategy and help to understand the mechanism of improving crop nutrient uptake and productivity in different rotations.

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Soil Phosphorus Exchange as Affected by Drying-Rewetting of Three Soils From a Hawaiian Climatic Gradient

Frontiers in Soil Science ◽

10.3389/fsoil.2021.738464 ◽

2021 ◽

Vol 1 ◽

Author(s):

Julian Helfenstein ◽

Emmanuel Frossard ◽

Chiara Pistocchi ◽

Oliver Chadwick ◽

Peter Vitousek ◽

...

Keyword(s):

Soil Phosphorus ◽

P Availability ◽

Climatic Gradient ◽

Soil Behavior ◽

P Concentration ◽

P Cycling ◽

Inherent Feature ◽

History Of ◽

Climatic History ◽

P Recovery

Current understanding of phosphorus (P) dynamics is mostly based on experiments carried out under steady-state conditions. However, drying-rewetting is an inherent feature of soil behavior, and as such also impacts P cycling. While several studies have looked at net changes in P pool sizes with drying-rewetting, few studies have dynamically tracked P exchange using isotopes, which would give insights on P mean residence times in a given pool, and thus P availability. Here, we subjected three soils from a climatic gradient on the Kohala peninsula from Hawaii to 5-month drying-rewetting treatments. The hypotheses were that physico-chemical and biotic processes would be differently affected by repeated drying-rewetting cycles, and that response would depend on climatic history of the soils. Soils were labeled with 33P and 18O enriched water. At select time intervals, we carried out a sequential extraction and measured P concentration, 33P recovery (only first 3 months), and incorporation of 18O from water into phosphate. This allowed tracing P dynamics in sequentially extracted pools as well as O dynamics in phosphate, which are driven by biological processes. Results showed that P concentration and 33P recovery were predominantly driven by soil type. However, across all soils we observed faster dilution of 33P from resin-P into less mobile inorganic pools under drying-rewetting. On the other hand, O dynamics in phosphate were mostly governed by drying-rewetting treatment. Under drying-rewetting, considerably less O was incorporated from water into phosphate of resin-P, microbial-P and HCl-P, suggesting that drying-rewetting reduced biological P cycling. Hence, our results suggest that repeated drying-rewetting increases inorganic P exchange while reducing biological P cycling due to reduced microbial activity, independent of climatic history of the soils. This needs to be considered in P management in ecosystems as well as model representations of the terrestrial P cycle.

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Improved Plant Diversity as a Strategy to Increase Available Soil Phosphorus

10.24047/bc103143 ◽

2019 ◽

Vol 103 (1) ◽

pp. 43-45 ◽

Cited By ~ 1

Author(s):

Carlos Crusciol ◽

João Rigon ◽

Juliano Calonego ◽

Rogério Soratto

Keyword(s):

Crop Yields ◽

Soil Phosphorus ◽

Cropping System ◽

P Availability ◽

P Fractions ◽

Crop Species ◽

Soil P ◽

Residue Decomposition ◽

Available Soil Phosphorus ◽

Crop Residue Decomposition

Some crop species could be used inside a cropping system as part of a strategy to increase soil P availability due to their capacity to recycle P and shift the equilibrium between soil P fractions to benefit the main crop. The release of P by crop residue decomposition, and mobilization and uptake of otherwise recalcitrant P are important mechanisms capable of increasing P availability and crop yields.

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