, Volume 1, Issue 3, pp 283–291 | Cite as

Impacts of chicken manure and peat-derived biochars and inorganic P alone or in combination on phosphorus fractionation and maize growth in an acidic ultisol

  • Muhammad Aqeel Kamran
  • Ren-Kou XuEmail author
  • Jiu-yu Li
  • Jung Jiang
  • Ren-Yong Shi
Original Article


The forms of phosphorus (P) in animal manure and peat are different from synthetic P fertilizers and will affect soil P fractions when they are used as P amendments. Effects of chicken manure (CMB) and peat (PB) derived biochars (CMB and PB) alone or in combination with P fertilizer (KH2PO4) and rock phosphate (RP) on plant/soil health and soil P fractions in an acidic ultisol were examined with greenhouse pot experiments. The total P rate was constant at 120 mg kg−1 in all treatments. Soil P fractions, P uptake, and maize growth were determined after 56 days. Application of CMB combined with P fertilizer or alone significantly increased soil pH, water extractable and relatively labile P, dry matter yield of maize, chlorophyll contents in maize leaves, while decreasing the Fe and Al binding P. Moreover, sole application of CMB and PB showed greater effects than application of P fertilizer alone regarding plant growth and P fractionation. Integration of synthetic inorganic P sources with CMB or sole application of CMB is more beneficial than application of inorganic P sources to improve plant growth and P availability.


Acidic soil Manure-derived biochar Peat-derived biochar Inorganic P fertilizer P fractions Plant P uptake 

1 Introduction

Phosphorus is an essential element for plant growth and development (Kamran et al. 2018b). However, its deficiency in plants is a serious problem in acidic soils. P availability in many acidic soils around the world is very low. In China about 22% of total arable land is suffering from soil acidification which leads to the deficient nutrient availability, especially low-available P values (Hong et al. 2018; Li et al. 2018). Therefore, continued higher application of P fertilizers in these acidic soils is required to maintain plant productivity. Unfortunately, it is estimated that less than 20% of fertilizer P can be used by crops during the growing season in China (Zhang et al. 2008). P is fixed in acidic soils through various mechanisms. Acidic soils usually contain great amounts of Fe and Al oxides. They react with phosphate and convert P into less soluble/available forms (Zhang et al. 2009). On the other hand, excessive application of P fertilizers in China to maintain plant growth in acidic soils led to severe eutrophication and other environmental constraints due to runoff (Zhang et al. 2012). Therefore, P management in acidic soils is necessary to improve P availability to plants and reduce P losses from the soils.

Organic amendments such as manures can be used as alternative to chemical fertilizer and other P sources (Kashem et al. 2004; Nziguheba et al. 1998). These manures can provide great amounts of essential nutrients in acidic soils and also improve other physiochemical properties of the highly weathered soils (Molnár et al. 2016). Application of manure amendments can initially build up P concentration in P-deficient soils as manures contain higher amount of P, but their repeated application can lead to environmental concerns regarding P losses by runoff and leaching. C/N/P ratios are not same in various manures, which makes them not suitable as organic amendments applied mostly on the basis of C/N ratio. Application of these amendments on the basis of C/N ratio resulted in excessive application of P in the soils which caused other potential issues (Liang et al. 2014).

To avoid these environmental concerns, converting manure into biochar is a good option. Thermal combustion of animal manure at low temperature in oxygen-limited conditions is recommended for soil amendment production to improve soil quality and physiochemical characteristics (Hass et al. 2012). Higher CEC, exchangeable cations, and functional groups of these manure-derived biochars can improve soil structure, nutrient sorption and enable more P retention in soils (Cao and Harris 2010). Manure biochar inhibits the P losses by reducing leaching and runoff. Addition of these organic amendments can greatly influence soil chemical properties, which ultimately affects the P magnitude and fractionations in acidic soils. Micro and macro nutrients present in manure-derived biochars significantly affected soil characteristics and productivity (DeLuca et al. 2009; Jin et al. 2016). Different forms of P in the biochars can also play a key role in soil P availability to plants in highly weathered soils.

Various organic amendments increased P concentrations and changed P forms in soils (Ajiboye et al. 2004; Sharpley and Moyer 2000). P species showed diverse behavior when these amendments were applied to different soil types, some species showed more conversion into plant-available P than others. Essential nutrients in organic amendments also affected the P forms and their stability in different types of soils. In acidic soils, various forms of P added by organic amendments have shown similarity in P availability to plants (Chan et al. 2008). Along with this, P availability has also been affected by changes that occurred in rhizosphere with increase in soil pH and plant–microbe interaction. Some other factors such as organic anion exudations, ligand exchange reactions, and enzymatic hydrolysis also influence P availability to plants. However, few studies have involved in the effect of manure biochar on P fractions and their availability to plants.

The effectiveness of mineral P and P from manure-derived biochars may differ from each other in terms of their availability to crops and their fractions in different soils (Xu et al. 2014). Comparison of these amendments can provide a detailed framework or strategy for proper management of these amendments in P-deficient acidic soils. Some previous studies suggested that P availability to plants was less affected by organic amendments; other studies reported that P from organic amendments is equally or more available than inorganic P from P fertilizers (Xu et al. 2014; Jin et al. 2016; Kamran et al. 2018a, b). Determining the forms of P by applying these inorganic and organic amendments can give clear information about the plant-available P.

Some attempts have been made to observe the changes in P fractions and P availability to crops by addition of manure into soils (Hansen et al. 2004; Hass et al. 2012), but very few studies investigated the effects of manure and peat-derived biochars on P fractions in acidic soils and P availability to crops. Moreover, very little attention has been given to combined application of these manure-derived biochars along with inorganic P fertilizer in acidic soils and its effect on P fractionation and P availability to plants. In the present study, the interactive effects of alone and co-application of P fertilizer with manure and peat-derived biochars on soil P fractionation and maize growth have been investigated. The hypothesis of the study was that there would be an interactive effect between fertilizer application and biochar treatment on soil P fractionation in acidic ultisol and plant P uptake. The objective of this study was to determine the effect of organic (manure and peat-derived biochars) and inorganic sources of P alone or combined on P fractions and P uptake by maize plant in an acidic ultisol with P deficiency.

2 Materials and methods

2.1 Soil and biochar preparation

The acidic ultisol used in this experiment was collected from top ~ 15 cm (A horizon) from Langxi (31°6′N, 119°8′E), Anhui Province of China. Soil sample was air dried. Vegetation and coarse minerals were removed and then ground to pass through < 2 mm aperture sieve. Basic properties of the soil are presented in Table 1. Soil pH was measured at a ratio of 1:2.5 w/v with deionized water by an Orion 720 pH meter (Orion Research Incorporated, Boston, MA, USA). Soil OM was measured with the dichromate method and CEC was determined with the ammonium acetate method at pH 7.0 (Pansu and Gautheyrou 2006). Soil exchangeable acidity was extracted with 1.0 M potassium chloride and then titrated against 0.01 M NaOH (Pansu and Gautheyrou 2006). Fe oxide was extracted using DCB method (Pansu and Gautheyrou 2006) and measured by atomic absorption spectrometry (nov AA350, Analytik Jena AG, Germany).
Table 1

Basic properties of the ultisol used in the experiment


Parental material





Organic matter

Fe oxide

Exchangeable acidity

Exchangeable H+

Exchangeable Al3+



(g kg−1)

(g kg−1)

(mmolc kg−1)

(cmolc kg−1)


Quaternary red earth











CEC cation exchange capacity

The biochars of organic amendments were prepared under oxygen-limited conditions. Briefly, manure and peat were air dried, and ground to pass through < 2 mm sieve. Then, the organic materials were placed in the ceramics crucible and fitted with lid for pyrolizing under oxygen-limited conditions in a muffle furnace (RH Corp., Shanghai, China). The furnace temperature was raised up to 400 °C for 4 h at the rate of 20 °C/min. After cooling at room temperature, biochars were used for further analysis. Basic properties of biochars are presented in Table 2. The pH and electric conductivity of biochar samples were measured at a ratio of 1:5 w/v with deionized water by an Orion 720 pH meter (Orion Research Incorporated, Boston, MA, USA) and EC 215 conductivity meter 143 (Hanna instruments, Padova, Italy), respectively (Xu and Zhao 2013). Volatile matter (VM) was determined using method D-1762-84 of the American Society for Testing and Materials (Jiang et al. 2015a). Ash was quantified as the mass loss by heating to 700 °C for 6 h, and fixed carbon content was determined as the difference between 100% and the additive of ash and VM (Jiang et al. 2015a). Total C, H, and N were determined by dry combustion using a Carlo Erba NA1500 NSC elemental analyzer (Haake Buchler Instruments, USA). The CEC of the biochars was measured by a modified NH4-acetate compulsory displacement method (Yuan et al. 2011).
Table 2

Properties of biochars produced from chicken manure (CMB) and peat (PB) at 400 ℃ for 4 h





Fixed C

Total C

Total N

Total H

Total P

Total K


(mS cm−1)

(g kg−1)


(g kg−1)

(cmolc kg−1)























EC electrical conductivity, VM volatile matter, C carbon, N nitrogen, H hydrogen, P phosphorus, K potassium, CEC cation exchange capacity

2.2 Experimental treatments

Prior to transplanting, soil sample was thoroughly mixed with the organic and inorganic amendments. There were nine treatments including the following: (1) control, (2) chicken manure biochar (CMB), P at the rate of 120 mg kg−1, (3) peat biochar (PB), P at the rate of 120 mg kg−1, (4) KH2PO4, P at the rate of 120 mg kg−1 (5) rock phosphate (RP), P at the rate of 120 mg kg−1, (6) CMB + KH2PO4, P at the rate of (60 + 60) mg kg−1, (7) CMB + RP, P at the rate of (60 + 60) mg kg−1, (8) PB + KH2PO4, P at the rate of (60 + 60) mg kg−1, (9) PB + RP, P at the rate of (60 + 60) mg kg−1. There were three replicates for each treatment.

2.3 Green house experiment

Maize was used for pot experiment, because it is a common crop in the region from where the soil sample was taken. The experiment was conducted for 8 weeks in greenhouse of the Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China, in natural light conditions during 2017. Temperature ranged from 25 to 27 °C during day time and around 18–20 °C in the night time. 2.5 kg of acidic Ultisol sample was placed in plastic pots. Basel dose of N and K was applied to reach the same rate of 200 mg N kg−1 as Urea and 80 mg K kg−1 as KOH in all treatments to meet the fertilizer requirements. 100 mg kg−1 N as urea was also added to maize crop for top dressing. Seeds of Zhengdan-958 maize variety were scarified with 10% H2O2 for 15 min and then washed several times with deionized water. After washing, seeds were placed on moist towels in trays and kept in dark in a growth chamber at 25 °C. After germination, seven seeds/pot were transferred to green house pots and thinned to five seeds per pot after one week. Deionized water was added through the experiment period to maintain 70% soil water holding capacity.

2.4 Plant and soil analyses

After 8 weeks, Chlorphyll content was measured with SPAD-502 plus chlorophyll meter (Konica Minolta Sensing, Tokyo, Japan) (Baquy et al. 2018). Then shoots and roots of maize crops were harvested separately and washed with deionized water several times. After washing, plants were placed in an oven at 70 °C for 48 h and then used for further analysis. The weights of plant shoots and roots were measured after oven drying. Plant samples were ground to measure the nutrient uptake by maize plants. The shoot P uptake was calculated using the following equation:
$$\begin{aligned} {\text{Shoot P uptake}}\;\left( {{\text{mg P}}\;\left( {\text{kg soil}} \right)^{ - 1} } \right) & \, = \,{\text{P in plant tissue }}\left( {{\text{mg}}\; {\text{g}}^{ - 1} } \right) \\ & \times \,{\text{plant biomass}}\;\left( {\text{g}} \right)/{\text{soil weight}}\;\left( {\text{kg}} \right). \\ \end{aligned}$$
After plant harvesting, soil sample was collected to measure pH and P fractions from each pot. Soil was air dried and ground to pass through < 2 mm sieve for further analysis. Soil pH was measured with the method mentioned above. The P fractions of the soil were measured by method of Hedley et al. (1982), which was further modified by Tiessen and Moir (1993) to use strong extractants that removed inorganic and organic phosphorus (Table 3). Briefly, 1 g of soil samples was placed in 50 mL tube and sequentially extracted with 30 mL of deionized water followed by 30 ml 0.5 M NaHCO3 at pH 8.5, 30 ml 0.1 M NaOH and 30 ml 1 M HCl. Soil residues were then digested with concentrated H2SO4 and 30% H2O2 to get organic P. After adding each extractant, the soil was shaken for 16 h and then centrifuged at 7000×g for 10 min at room temperature. Supernatant was filtered with 0.45 μm cellulose membrane filter. 5 mL extract from each extractant was used to determine reactive P (inorganic fraction) by ascorbic acid method (Murphy and Riley 1962). Another 5 mL of the same extract was oxidized with persulfate to decompose organic matter and P in digesting solution was determined to represent total P. Organic P of each extractant was calculated by the difference between inorganic and total P.
Table 3

Soil P fractions scheme used in the experiment


P fractions


Time (h)


Fairly labile, Pi (mobile P)

Deionized water



Relatively labile Pi, microbial P, Po adsorbed on soil surface

0.5 M NaHCO3



Crystalline Fe and Al phosphates, as well as P strongly bound by chemisorption to Fe and Al compounds

0.1 M NaOH



Al–P and Fe–P

1 M HCl



Residue P

Concentrated H2SO4 and 30% H2O2


2.5 Statistical analysis

SPSS 20.0 (SPSS Inc., Chicago, IL, USA) and origin Pro 9.0 were used for the statistical analysis of the data. Analysis of variance (ANOVA) was used to test the significant differences (p < 0.05) among the different treatments.

3 Results

3.1 Biochar characteristics and effects of various amendments on soil pH

The chemical properties of biochars are given in Table 1. Total N, H, C, and P contents were higher in CMB than PB. The pH, CEC, and EC were also higher in CMB. Fixed C and ash content were greater in CMB than in PB. Higher nutrient contents in CMB are due to the quality of char material. It indicates that biochar is in more stable conjugated aromatic structures than in the feedstocks (Enders et al. 2012; Krull et al. 2009). The contents of heavy metals differed between the two biochars: CMB contained 1.03, 0.13, 109.1 and 361.3 mg kg−1 of Pb, Cd, Cu, and Zn, respectively; and PB had 19.4, 0.23, 104.5, and 88.4 mg kg−1 of the corresponding metals (Kamran et al. 2018a, b).

The soil was low in nutrient availability with low CEC and higher exchangeable acidity (Table 1). Application of both biochars alone and combined with inorganic P sources ameliorated soil acidity and thus increased soil pH significantly (p < 0.05) (Fig. 1). Sole application of CMB increased soil pH more than PB and other treatments compared with control. Soil pH was increased by 0.48 and 0.22 units with CMB and PB applied, respectively. This trend was consistent with the pH of both biochars (Table 2). The soil pH increased with biochars due to proton consumption reactions. The biochar alkalinity and higher ash content play a key role to improve soil pH. In addition, ligand exchange reactions between the P anion and functional groups on biochars with soil Al–OH and Fe–OH lead to release of OH and also contribute to increase in soil pH (McBride 1994).
Fig. 1

The post-harvest pH of soil with different P amendments at a rate of 120 mg P kg−1 at the end of 56 days (n = 3). Error bars represent standard errors. Different letters on pillars show significant differences among the treatments (P < 0.05). CK control, B1 chicken manure biochar, B2 peat biochar, P1 KH2PO4, P2 rock phosphate

3.2 Effects of various amendments on soil P fractions

Application of high-quality organic P source such as CMB alone and in combination with inorganic P sources increased labile inorganic P. RP had greater water extractable P than the control treatment. Water extractable P fraction was higher in combined application of CMB with KH2PO4 than the control and all other treatments, while RP yielded the lowest water extractable P among all treatments which was significantly lower than the other amendments (Table 4). The values of water extractable P in the treatments with CMB and PB applied alone or PB combined with KH2PO4 were intermediate compared with application of KH2PO4 or RP alone. Similar trends were observed for NaHCO3 extracted Pi. The overall concentration of NaHCO3–Pi was higher than the water extractable P in all treatments. The NaHCO3–Pi fraction increased when CMB applied with KH2PO4. However, when the different amendments were applied solely, the CMB increased NaHCO3–Pi more than PB alone or in combination with KH2PO4 and RP. Moreover, the difference in NaHCO3–Po with different amendment application was also significant among treatments (Table 4). NaHCO3–Po was significantly higher in CMB combined with KH2PO4 than other treatments (Table 4). Easily available Pi, the sum of H2O–P and NaHCO3–Pi, was higher in the treatment of CMB combined with KH2PO4 followed by the application of CMB alone. Sole and combined application of CMB and KH2PO4 increased the labile and moderately labile P fractions. However, the combined application of CMB with KH2PO4 is more effective than that both applied solely. Increase in labile or easily available P in CMB treatment reflects the higher P content in soluble form. Higher P content in manure biochar was also reported by some previous studies (Hansen et al. 2004; Jin et al. 2016). Moreover, higher available P in the treatment of CMB + KH2PO4 than CMB or KH2PO4 alone indicated that the high-quality organic source P inhibited inorganic P adsorption and increased available P in soil solution. A previous study by Iyamuremye et al. (1996) also found similar results. They found that addition of manure residues increased soil-available P (water soluble and bicarbonate P).
Table 4

Effects of biochars and inorganic P sources added into the acidic ultisol on soil P fractions (mg kg−1)










2.6 ± 0.5d

8.8 ± 0.6g

61.4 ± 2.2e

71.5 ± 2.2g

158.6 ± 3.6d

135.1 ± 2.1f

11.4 ± 0.7f


6.1 ± 0.2bc

19.4 ± 0.4a

87.7 ± 3.0b

99.8 ± 2.7c

160.2 ± 5.5cd

155.4 ± 4.7d

22.0 ± 2.6cd


4.4 ± 0.6cd

15.8 ± 1.1cd

79.7 ± 2.3c

107.7 ± 2.1b

161.8 ± 8.5cd

160.7 ± 4.7bc

26.4 ± 0.9bc


7.9 ± 0.5b

18.5 ± 1.5b

69.8 ± 4.4d

120.1 ± 4.4a

165.6 ± 11.2b

164.3 ± 6.2b

13.2 ± 0.8rf


3.5 ± 0.1cd

10.5 ± 0.8fg

66.3 ± 5.8d

120.1 ± 2.4a

173.7 ± 4.4a

171.3 ± 8.5a

12.3 ± 0.5f

CMB + Pi

10.5 ± 0.4a

22.9 ± 1.0a

92.6 ± 3.5a

77.7 ± 5.1f

159.9 ± 13.2cd

159.8 ± 7.8c

17.6 ± 1.1de


5.2 ± 0.7cd

15.0 ± 0.8de

77.0 ± 2.2c

87.4 ± 2.6e

162.7 ± 4.3bc

157.2 ± 2.3cd

35.3 ± 3.1a

PB + Pi

7.9 ± 0.6b

17.6 ± 1.7bc

85.7 ± 3.8b

90.9 ± 4.6d

171.3 ± 6.2a

148.4 ± 4.2e

26.4 ± 1.0c


5.2 ± 0.6cd

13.2 ± 2.1ef

78.1 ± 4.5c

97.1 ± 3.0c

165.9 ± 10.9b

161.6 ± 7.8c

30.0 ± 3.2b

Data are shown as means of three replicates ± SD. Different letters on the same column indicate significant difference at p < 0.05

CMB chicken manure biochar, PB peat biochar, Pi KH2PO4, RP rock phosphate

The NaOH–P fraction was generally associated with less available P due to binding with Fe and Al oxides and presented on adsorption sites. NaOH–P was greater in application of KH2PO4 or RP alone and the concentration of NaOH–Pi decreased in CMB alone or combined application with KH2PO4 (Table 4). Moreover, NaOH–Po was higher in RP treatment alone, while CMB + KH2PO4 had lower NaOH–Po than all other treatments (Table 4). The HCl–P fraction generally reflects the insoluble mineral P, especially Fe and Al bound. In present study, the treatments with application of RP or KH2PO4 alone contained the highest HCl–P, while the combined application of biochars with KH2PO4 (CMB + KH2PO4 followed by PB + KH2PO4) and the sole application of CMB and PB contained intermediate HCl–P compared with other treatments (Table 4). Residual-P which is more chemically stable Po form and relatively insoluble Pi form has less proportion of total P percentage in this study (Table 4).

3.3 Effects of various amendments on phosphorus uptake and plant growth

Dry matter yield of maize was significantly enhanced by CMB alone or combined application with KH2PO4 (p < 0.05) (Figs. 2 and 3). Significant interactions were observed between KH2PO4, CMB and PB effects. The dry matter (shoot dry weight and root dry weight) of plant was higher in sole or combined application of biochar amendments than KH2PO4 sole application. Shoot dry weight was higher in CMB alone application followed by CMB combined with KH2PO4 and then other treatments (Fig. 2). The root dry weight was higher in CMB alone application followed by CMB + KH2PO4, PB, and then other treatments (Fig. 3). Similar results were observed for chlorophyll content (Fig. 4). Chlorophyll content was higher in CMB application followed by CMB + KH2PO4, PB and PB + KH2PO4. However, the lowest chlorophyll contents among different amendments were found in alone application of P fertilizers either KH2PO4 or RP.
Fig. 2

The shoot dry weight of maize with different P amendments at a rate of 120 mg P kg−1 at the end of 56 days (n = 3). Error bars represent standard errors. Different letters on pillars show significant differences among the treatments (P < 0.05). CK control, B1 chicken manure biochar, B2 peat biochar, P1 KH2PO4, P2 rock phosphate

Fig. 3

The root dry weight of maize with different P amendments at a rate of 120 mg P kg−1 at the end of 56 days (n = 3). Error bars represent standard errors. Different letters on pillars show significant differences among the treatments (P < 0.05). CK control, B1 chicken manure biochar, B2 peat biochar, P1 KH2PO4, P2 rock phosphate

Fig. 4

The chlorophyll content of maize leaves with different P amendments at a rate of 120 mg P kg−1 at the end of 56 days (n = 3). Error bars represent standard errors. Different letters on pillars show significant differences among the treatments (P < 0.05). CK control, B1 chicken manure biochar, B2 peat biochar, P1 KH2PO4, P2 rock phosphate)

For maize P uptake, sole application of two biochars and KH2PO4 and combined application of two biochars with KH2PO4 and RP all significantly increased P uptake by maize (p < 0.05) (Fig. 5). CMB with KH2PO4 increased the uptake of P to the greatest extent and P content in maize shoots was significantly higher than other treatments (p < 0.05) (Fig. 5). Phosphorus uptake by maize plant in combined application of CMB and PB with KH2PO4 was higher than that in corresponding sole application of CMB, PB and KH2PO4. For sole application treatments, CMB application significantly increased the P content in maize shoots to the greatest extent, followed by PB and then KH2PO4 (P < 0.05). The application of RP did not increase P uptake by maize significantly.
Fig. 5

The cumulative amounts of maize shoot P uptake with different P amendments at a rate of 120 mg P kg−1 at the end of 56 days (n = 3). Error bars represent standard errors. Different letters on pillars show significant differences among the treatments (P < 0.05). CK control, B1 chicken manure biochar, B2 peat biochar, P1 KH2PO4, P2 rock phosphate)

4 Discussion

4.1 Effects of various amendments on soil P fractions

The distribution of different P fractions reflects the quality of applied P sources. CMB and CMB + KH2PO4 treatments showed significant increase in available P fractions by sequential extraction method. The increase in labile P by the addition of CMB reflects the large amount of P present in the manure-derived biochar. Higher amount of H2O–P availability with application of CMB + KH2PO4 and alone application of CMB rather than sole or combined application of RP and PB reflected the influence of CMB on increased P availability and decreased P adsorption by the soil. Higher available P content was observed in the treatment of CMB + KH2PO4 compared with CMB + RP. This was due to the changes in soil properties as well as higher availability of P in CMB and KH2PO4. However, the less available P content in RP reduced P availability in the soil. NaOH–P generally described as less available or sorbed P due to Fe and Al oxides. CMB sole or CMB + KH2PO4 treatments decreased NaOH–P more than all other treatments, which showed the role of biochar in P adsorption and desorption. Generally there was significant difference among the organic P pool as well as inorganic P pool. Incorporation of CMB with KH2PO4 showed significant increase in plant-available P over the other treatments and control, and decrease in NaOH–P. Phosphorus availability to plants was affected by several processes like adsorption of P to Fe and Al oxides, mineralization, dissolution and precipitation to mineral pools (Li et al. 2011). The acidic soils have higher P sorption capacity than calcareous soils which was due to the presence of high amounts of free Fe and Al oxides. In the present study, the phosphorus availability in the acidic ultisol was also mainly affected by the adsorption of Fe and Al oxides. Organic amendments positively affected P distribution and P fractionation in the soil (Kashem et al. 2004; Xu et al. 2014). Application of such materials which have high contents of organic matter can decrease P adsorption by soil surface due to competition of organic compounds with phosphate for adsorption sites on soils. Our results is supported by the previous study of Cui et al. (2011) who observed that application of biochar decreased P adsorption on ferrihydrite and that P desorption was increased by combined application of P with biochar. The results presented in this study were also consistent with previous reports by others (Iyamuremye et al. 1996; Kashem et al. 2004).

Incorporation of biochar alone or in combination with synthetic P fertilizer increased the negative surface charge on the soil which increased the repulsion of soil surface to phosphate and thus decreased phosphate adsorption by the soil (Jiang et al. 2015b). Manure biochar is also a rich source of phosphorus and using manure biochar as organic amendment can be a valuable solution to cater P scarcity in acidic soils. Biochar has ability to influence soil P availability in acidic soils by changing soil pH and soil sorption capacity. Biochar reduced adsorption of phosphate to Fe and Al oxides by increasing soil pH (Atkinson et al. 2010; Maranguit et al. 2017). Soil P availability had been increased by biochar application while P sorption to Fe and Al oxides had been decreased. The use of manure-derived biochar in an increasingly P-constrained agricultural industry appears attractive.

In this study CMB was more effective than PB. Biochar properties mainly depend on char material. It is due to higher nutrient content in manure than peat. CMB has higher pH and CEC. Application of CMB increased the soil pH and CEC and thus improved soil quality. Some studies also suggested that soil P availability was increased due to increasing soil pH (Barrow 2017; Kamran et al. 2018a, b). In this study, increased soil pH was one of the factors which increased soil P availability along with desorption of P from the soil. Results of previous studies suggested that application of biochar alone or in combination with fertilizer enhanced P availability by improving the soil’s physical and chemical properties, such as soil surface area, soil microbial community, soil water holding capacity, and soil CEC, which improved soil health and plant growth. In the present study, combined application of CMB with KH2PO4 or alone application of CMB significantly increased the soil P availability. However, the PB application alone or combined with KH2PO4 was intermediate between CMB and P fertilizer alone application.

4.2 Effects of various amendments on phosphorus uptake and plant growth

Statistical analyses suggested that effects of amendments were significant on soil pH, plant growth, and P uptake by maize plant. Higher nutrient values and pH of biochar resulted in increased soil pH which ultimately increased nutrient uptake due to better plant growth (Silber et al. 2010). CMB was rich in other essential nutrients which increased soil fertility and plant dry matter yield as compared to other treatments. The higher pH of CMB led to more increase in post-harvest soil pH than PB (Fig. 1). The increase in soil pH by addition of biochar resulted in higher plant dry weight by increasing essential nutrient availability to plants (Anugoolprasert et al. 2012). The higher base cations in applied biochar increased soil Ca2+, Mg2+, and K+ contents significantly, which also contributed to the increase in plant dry biomass. Previous studies showed that plant mass was higher in the treatment with organic amendments applied compared to synthetic fertilizer application (Carry and Gunn 2003). Organic amendments improved soil fertility which ultimately improved plant growth. Addition of macro- and micronutrients affected the soil P dynamics by improving soil characteristics which behaves differently in sole application of P fertilizer and other treatments (Jindo et al. 2012).

Results presented in this study showed that the changes in soil P fractions significantly affected the P uptake by maize plant. Labile and moderately labile P are positively correlated with the P uptake by maize plant (Table 5). The P availability to maize plant was higher in those treatments which have the higher labile P contents. Combined application of CMB with KH2PO4 has higher available P fractions from all other treatments which increased the P availability to plant to the greatest extent.
Table 5

The correlation between P fractions and soil and plant characteristics multivariate ANOVA


Shoot biomass

Root biomass


P uptake







Labile Pi






























NS Non-significant

*p ≤ 0.05, **p ≤ 0.01, significant correlation coefficients, Labile-P = H2O–P + NaHCO3–P

Lone application of RP and KH2PO4 has lower labile P fractions in acidic soils which led to lower P uptake by maize plant as well. However, when biochars were applied alone the P uptake by maize plants was higher in CMB than that in PB. Combined application of inorganic P fertilizer with biochar had more effect on P availability than sole application of inorganic P fertilizer. This is due to the changes in soil properties by application of the biochar. The combined application of inorganic and high-quality organic amendments was found to be more effective to enhance P uptake by plants in acidic soils. Results of present study suggested that application of high-quality organic P source could be a better option to improve plant growth and development in acidic soils.

5 Conclusions

The CMB as high-quality organic amendment showed great positive effects on soil chemical properties and P fractions, thus improved maize growth and increased P uptake by the plant. The CMB application was effective in increasing soil pH, chlorophyll contents, and dry weight of plants. Combined application of CMB with KH2PO4 resulted in the greatest increase in soil labile P followed by CMB alone. This increase was due to the release of P from applied sources and the decrease in P adsorption to Fe and Al oxides by biochar addition. The P uptake by plants was also greater in the combination of CMB with KH2PO4. This treatment also has other benefits associated with integrated soil fertility management. The sole application of CMB and PB increased the P availability to plant to greater extent than application of KH2PO4 alone due to improving soil characteristics by application of these biochars. The combination of CMB with KH2PO4 is more suitable for the plant growth and soil fertility improvement of acidic soils. Future research is needed to examine the effects of these treatments on transformations of P and the effect of application rate of P in acidic soils where P availability is a major problem.



This study was supported by the National Key Research and Development of China (No. 2016YFD0200302). The first author is highly grateful to CAS-TWAS President’s Fellowship for his PhD studies in China.


  1. Ajiboye B, Akinremi O, Racz G (2004) Laboratory characterization of phosphorus in fresh and oven-dried organic amendments. J Environ Qual 33:1062–1069CrossRefGoogle Scholar
  2. Anugoolprasert O, Kinoshita S, Naito H, Shimizu M, Ehara H (2012) Effect of low pH on the growth, physiological characteristics and nutrient absorption of sago palm in a hydroponic system. Plant Prod Sci 15:125–131CrossRefGoogle Scholar
  3. Atkinson CJ, Fitzgerald JD, Hipps NA (2010) Potential mechanisms for achieving agricultural benefits from biochar application to temperate soils: a review. Plant Soil 337:1–18CrossRefGoogle Scholar
  4. Baquy MAA, Li JY, Shi RY, Kamran MA, Xu RK (2018) Higher cation exchange capacity determined lower critical soil pH and higher Al concentration for soybean. Environ Sci Pollut Res 25:6980–6989CrossRefGoogle Scholar
  5. Barrow NJ (2017) The effects of pH on phosphate uptake from the soil. Plant Soil 410:401–410CrossRefGoogle Scholar
  6. Cao X, Harris W (2010) Properties of dairy-manure-derived biochar pertinent to its potential use in remediation. Bioresour Technol 101:5222–5228CrossRefGoogle Scholar
  7. Chan K, Van Zwieten L, Meszaros I, Downie A, Joseph S (2008) Using poultry litter biochars as soil amendments. Soil Res 46:437–444CrossRefGoogle Scholar
  8. Cui HJ, Wang MK, Fu ML, Ci E (2011) Enhancing phosphorus availability in phosphorus-fertilized zones by reducing phosphate adsorbed on ferrihydrite using rice straw-derived biochar. J Soils Sediments 11:1135–1141CrossRefGoogle Scholar
  9. DeLuca T, Derek MacKenzie M, Gundale M (2009) Biochar effects on soil nutrient transformation. Biochar for environmental management: science and technology. Earthscan Publications Ltd, London, pp 251–270Google Scholar
  10. Enders A, Hanley K, Whitman T, Joseph S, Lehmann J (2012) Characterization of biochars to evaluate recalcitrance and agronomic performance. Bioresour Technol 114:644–653CrossRefGoogle Scholar
  11. Hansen JC, Cade-Menun BJ, Strawn DG (2004) Phosphorus speciation in manure-amended alkaline soils. J Environ Qual 33:1521–1527CrossRefGoogle Scholar
  12. Hass A, Gonzalez JM, Lima IM, Godwin HW, Halvorson JJ, Boyer DG (2012) Chicken manure biochar as liming and nutrient source for acid Appalachian soil. J Environ Qual 41:1096–1106CrossRefGoogle Scholar
  13. Hedley MJ, Stewart J, Chauhan B (1982) Changes in inorganic and organic soil phosphorus fractions induced by cultivation practices and by laboratory incubations. Soil Sci Soc Am J 46:970–976CrossRefGoogle Scholar
  14. Hong ZN, Shi RY, Li JY, Jiang J, Kamran MA, Xu RK, Qian W (2018) Peanut straw biochar increases the resistance of two Ultisols derived from different parent materials to acidification: a mechanism study. J Environ Manag 210:171–179CrossRefGoogle Scholar
  15. Iyamuremye F, Dick RP, Baham J (1996) Organic amendments and phosphorus dynamics: I. Phosphorus chemistry and sorption. Soil Sci 161:426–435CrossRefGoogle Scholar
  16. Jiang J, Peng YB, Yuan M, Hong ZN, Wang DJ, Xu RK (2015a) Rice straw-derived biochar properties and functions as Cu(II) and cyromazine sorbents as Influenced by pyrolysis temperature. Pedosphere 25:781–789CrossRefGoogle Scholar
  17. Jiang J, Yuan M, Xu RK, Bish DL (2015b) Mobilization of phosphate in variable-charge soils amended with biochars derived from crop straws. Soil Till Res 146:139–147CrossRefGoogle Scholar
  18. Jin Y, Liang X, He M, Liu Y, Tian G, Shi J (2016) Manure biochar influence upon soil properties, phosphorus distribution and phosphatase activities: a microcosm incubation study. Chemosphere 142:128–135CrossRefGoogle Scholar
  19. Jindo K, Martim SA, Navarro EC, Pérez-Alfocea F, Hernandez T, Garcia C, Aguiar NO, Canellas LP (2012) Root growth promotion by humic acids from composted and non-composted urban organic wastes. Plant Soil 353:209–220CrossRefGoogle Scholar
  20. Kamran MA, Jiang J, Li JY, Shi RY, Mehmood K, Abdulaha-Al Baquy M, Xu RK (2018a) Amelioration of soil acidity, Olsen-P, and phosphatase activity by manure-and peat-derived biochars in different acidic soils. Arab J Geosci 11:272CrossRefGoogle Scholar
  21. Kamran MA, Xu RK, Li JY, Jiang J, Nkoh JN (2018b) Effect of different phosphorus sources on soybean growth and arsenic uptake under arsenic stress conditions in an acidic Ultisol. Ecotox Environ Safe 165:11–18CrossRefGoogle Scholar
  22. Kashem MA, Akinremi OO, Racz GJ (2004) Phosphorus fractions in soil amended with organic and inorganic phosphorus sources. Can J Soil Sci 84:83–90CrossRefGoogle Scholar
  23. Krull ES, Baldock JA, Skjemstad JO, Smernik RJ (2009) Characteristics of biochar: organo-chemical properties. Biochar for environmental management: science and technology. Earthscan Publications Ltd, London, pp 251–270Google Scholar
  24. Li H, Huang G, Meng Q, Ma L, Yuan L, Wang F, Zhang W, Cui Z, Shen J, Chen X (2011) Integrated soil and plant phosphorus management for crop and environment in China. A review. Plant Soil 349:157–167CrossRefGoogle Scholar
  25. Li JY, Shi RY, Jiang J, Kamran MA, Xu RK, Qian W (2018) Incorporation of corn straw biochar inhibited the re-acidification of four acidic soils derived from different parent materials. Environ Sci Pollut Res 25:9662–9672CrossRefGoogle Scholar
  26. Liang Y, Cao X, Zhao L, Xu X, Harris W (2014) Phosphorus release from dairy manure, the manure-derived biochar, and their amended soil: effects of phosphorus nature and soil property. J Environ Qual 43:1504–1509CrossRefGoogle Scholar
  27. Maranguit D, Guillaume T, Kuzyakov Y (2017) Land-use change affects phosphorus fractions in highly weathered tropical soils. CATENA 149:385–393CrossRefGoogle Scholar
  28. McBride M (1994) Environmental chemistry of soils. Oxford University Press, New YorkGoogle Scholar
  29. Molnár M, Vaszita E, Farkas É, Ujaczki É, Fekete-Kertész I, Tolner M, Klebercz O, Kirchkeszner C, Cruiz K, Uzinger N, Feigl V (2016) Acidic sandy soil improvement with biochar—a microcosm study. Sci Total Environ 563:855–865CrossRefGoogle Scholar
  30. Murphy J, Riley JP (1962) A modified single solution method for the determination of phosphate in natural waters. Anal Chim Acta 27:31–36CrossRefGoogle Scholar
  31. Nziguheba G, Palm CA, Buresh RJ, Smithson PC (1998) Soil phosphorus fractions and adsorption as affected by organic and inorganic sources. Plant Soil 198:159–168CrossRefGoogle Scholar
  32. Pansu M, Gautheyrou J (2006) Handbook of soil analysis: mineralogical, organic and Inorganic methods. Springer Verlag, HeidelbergCrossRefGoogle Scholar
  33. Sharpley A, Moyer B (2000) Phosphorus forms in manure and compost and their release during simulated rainfall. J Environ Qual 29:1462–1469CrossRefGoogle Scholar
  34. Silber A, Levkovitch I, Graber E (2010) pH-dependent mineral release and surface properties of cornstraw biochar: agronomic implications. Environ Sci Technol 44:9318–9323CrossRefGoogle Scholar
  35. Tiessen H, Moir J (1993) Characterization of available P by sequential extraction. Soil sampling and methods of analysis. CRC Press, Boca Raton, pp 5–229Google Scholar
  36. Xu RK, Zhao AZ (2013) Effect of biochars on adsorption of Cu(II), Pb(II) and Cd(II) by three variable charge soils from southern China. Environ Sci Pollut Res 20:8491–8501CrossRefGoogle Scholar
  37. Xu G, Sun J, Shao H, Chang SX (2014) Biochar had effects on phosphorus sorption and desorption in three soils with differing acidity. Ecol Eng 62:54–60CrossRefGoogle Scholar
  38. Yuan JH, Xu RK, Zhang H (2011) The forms of alkalis in the biochar produced from crop residues at different temperatures. Bioresour Technol 102:3488–3497CrossRefGoogle Scholar
  39. Zhang R, Wu F, Liu C, Fu P, Li W, Wang L, Liao HQ, Guo JY (2008) Characteristics of organic phosphorus fractions in different trophic sediments of lakes from the middle and lower reaches of Yangtze River region and Southwestern Plateau, China. Environ Pollut 152:366–372CrossRefGoogle Scholar
  40. Zhang HM, Wang BR, Xu MG, Fan TL (2009) Crop yield and soil responses to long-term fertilization on a red soil in southern China. Pedosphere 19:199–207CrossRefGoogle Scholar
  41. Zhang F, Cui Z, Chen X, Ju X, Shen J, Chen Q, Liu XJ, Zhang WF, Mi GH, Fan MS (2012) Integrated nutrient management for food security and environmental quality in China. Adv Agron 116:1–40CrossRefGoogle Scholar

Copyright information

© Shenyang Agricultural University 2019

Authors and Affiliations

  • Muhammad Aqeel Kamran
    • 1
    • 2
  • Ren-Kou Xu
    • 1
    Email author
  • Jiu-yu Li
    • 1
  • Jung Jiang
    • 1
  • Ren-Yong Shi
    • 1
  1. 1.State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil ScienceChinese Academy of SciencesNanjingChina
  2. 2.University of Chinese Academy of SciencesBeijingChina

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