Soil-available phosphorus as evaluated by desorption techniques and chemical extractions

2001 ◽  
Vol 81 (2) ◽  
pp. 167-174 ◽  
Author(s):  
N. Ziadi ◽  
R R Simard ◽  
T S Tran ◽  
G. Allard
Keyword(s):  
Anion Exchange ◽  
High Capacity ◽  
P Uptake ◽  
Available Phosphorus ◽  
Anion Exchange Membranes ◽  
Soil P ◽  
Soil Available Phosphorus ◽  
Chemical Extractions ◽  
Close Relationship ◽  
P Desorption

The P-supplying power of the fine-textured soils from Abitibi-Temiscaming (Quebec, Canada) has never been investigated. Anion exchange membranes (AEM), the electro-ultrafiltration (EUF) technique and chemical extractions were used to describe their P status. Phosphorus was desorbed from four soils that had received 52.4 kg P ha–1 yr–1 from 1994 to 1996 and from unfertilized soils. The cumulative amount of P desorbed in 75 min by EUF from unfertilized soils varied from 10 to 69 mg P kg–1. Averaged over all sites and treatments, the amount of soil P extracted by different methods ranged from 1.0 to 18.9 mg P kg–1. The cumulative grass P uptake was significantly related to P desorbed by all methods (0.39 < r < 0.84). A close relationship between grass P uptake and PAEMs indicated the adequacy of the AEMs to determine plant-available P in Abitibi-Temiscaming soils. A high degree of linearity (0.97 < R2 < 0.99) of the EUF-P desorption curves at 200 V and 20°C with time was obtained. This indicates that soils have a high capacity to buffer removal of P from soil solution with reserve P. The EUF technique has shown that these soils hold very large inorganic P reserves and this may explain the lack of grass response to P fertilizers. Key words: Anion exchange membranes, grass-P uptake, P-desorption, Mehlich3-P, Olsen-P.

High‐capacity multimodal anion‐exchange membranes for polishing of therapeutic proteins

2021 ◽  
Author(s):  
Joshua Osuofa ◽  
Daniel Henn ◽  
Jinxiang Zhou ◽  
Anna Forsyth ◽  
Scott M. Husson
Keyword(s):  
Anion Exchange ◽  
Therapeutic Proteins ◽  
High Capacity ◽  
Anion Exchange Membranes

Response by sugar beet to superphosphate, particularly in relation to soils containing little available phosphorus

1976 ◽  
Vol 86 (1) ◽  
pp. 181-187 ◽  
Author(s):  
A. P. Draycott ◽  
M. J. Durrant
Keyword(s):  
Sugar Beet ◽  
Soil Phosphorus ◽  
Maximum Yield ◽  
P Uptake ◽  
Available Phosphorus ◽  
Triple Superphosphate ◽  
Phosphorus Fertilizer ◽  
Average Yield ◽  
Soil P ◽  
The Cost

SUMMARYTwenty experiments between 1970 and 1974 tested the effect of five amounts of triple superphosphate (0–110 kg P/ha) on sugar-beet yield in fields where soil contained little sodium bicarbonate-soluble phosphorus. The average yield without phosphorus fertilizer was 6·69 t/ha sugar and the increase from the optimum dressing 0·46 t/ha; the average soil concentration was 12 mg P/l. The fertilizer increased yield by 0·77 t/ha sugar on fields with 0–9 mg/l soil phosphorus, by 0·31 t/ha when soil phosphorus was 10–15 mg/l and had little effect on soils containing larger amounts.The concentration of phosphorus in plants harvested in mid-summer contained on average 0·29% P in dried tops and 0·13% in roots when given no phosphorus fertilizer, representing a total of 19·3 kg/ha P uptake. Giving superphosphate increased the phosphorus in both dried tops and roots by up to 0·03% and there was 3·7 and 1·7 kg/ha more phosphorus in tops and roots respectively. On the most responsive fields (0–9 mg/l soil P), the fertilizer increased the phosphorus in tops and roots by 0·05% and total uptake by 7 kg P/ha. The increase in uptake (or recovery) of fertilizer varied from 15% when 14 kg P/ha was given to less than 5% when 110 kg P/ha was used.A dressing of 27 kg P/ha was adequate for maximum yield on 19 of the 20 fields. When fields were grouped, 0–9, 10–15, 16–25 and > 26 mg/l NaHCO3-soluble soil phosphorus, and taking into account the value of the increased sugar yield, the cost of the fertilizer and its residual value, 60, 30, 20 and 10 kg P/ha respectively were the most profitable dressings. These experiments provide evidence, however, that the fertilizer would be used more efficiently if fields containing 0–9 mg soil phosphorus were subdivided into those with 0–4·5 and those with 4·6–9·0 mg/l and the groups given 80 and 40 kg P/ha respectively. These recommendations are substantially less than those used at present; they are adequate for sugar beet but other crops in the rotation would need similar close examination to ensure maximum yield and maintain adequate soil reserves of phosphorus.

Biological farming for sustainable agricultural production

1995 ◽  
Vol 35 (7) ◽  
pp. 849 ◽  
Author(s):  
CM Penfold ◽  
MS Miyan ◽  
TG Reeves ◽  
IT Grierson
Keyword(s):  
Weed Management ◽  
Environmental Sustainability ◽  
Large Scale ◽  
Farming Systems ◽  
Available Phosphorus ◽  
Economic Returns ◽  
Soil P ◽  
Soil Available Phosphorus ◽  
Term Trial ◽  
Biological Farming

In 1989, funding was provided to establish a large-scale (16-ha), long-term trial at Roseworthy campus. The trial aims to compare organic, biodynamic, integrated, and conventional broadacre farming systems for attributes of sustainability. It is overseen by a 13-member management committee comprising farmers with experience in each practice, agronomists, and soil scientists. Through the monitoring of indicators such as soil physical, chemical, and biological changes, product quality, economics, crop water usage, and energy requirements, the comparative advantages or disadvantages of each system are being evaluated in terms of productivity, profitability, and environmental sustainability. After 6 years, significant differences between systems are apparent in economic returns and soil available phosphorus (P) levels. The biodynamic treatment has the highest gross margins, followed by conventional, organic, and integrated. Conversely, available P levels on the biodynamic and organic treatments have declined 12 and 9%, respectively, since the start of the trial, while both the integrated and conventional treatments have increased soil P levels. In summary, it is too early in the trial to state categorically that any one system is more sustainable than another, although trends are now emerging. Weed management remains the main impediment to high production levels on the organic and biodynamic treatments, while input costs, variable yields, and low returns for grazed pastures are major constraints to high economic returns on the integrated and conventional systems.

scholarly journals Estimating Soil Available Phosphorus Content through Coupled Wavelet–Data-Driven Models

2020 ◽  
Vol 12 (5) ◽  
pp. 2150 ◽  
Author(s):  
Jalal Shiri ◽  
Ali Keshavarzi ◽  
Ozgur Kisi ◽  
Sahar Mohsenzadeh Karimi ◽  
Sepideh Karimi ◽  
...  
Keyword(s):  
Gene Expression Programming ◽  
Soil Phosphorus ◽  
Clay Content ◽  
The Other ◽  
Data Driven ◽  
Support Vector ◽  
Available Phosphorus ◽  
Discrete Wavelet ◽  
Soil P ◽  
Soil Available Phosphorus

Soil phosphorus (P) is a vital but limited element which is usually leached from the soil via the drainage process. Soil phosphorus as a soluble substance can be delivered through agricultural fields by runoff or soil loss. It is one of the most essential nutrients that affect the sustainability of crops as well as the energy transfer for living organisms. Therefore, an accurate simulation of soil phosphorus, which is considered as a point source pollutant in elevated contents, must be performed. Considering a crucial issue for a sustainable soil and water management, an effective soil phosphorus assessment in the current research was conducted with the aim of examining the capability of five different wavelet-based data-driven models: gene expression programming (GEP), neural networks (NN), random forest (RF), multivariate adaptive regression spline (MARS), and support vector machine (SVM) in modeling soil phosphorus (P). In order to achieve this goal, several parameters, including soil pH, organic carbon (OC), clay content, and soil P data, were collected from different regions of the Neyshabur plain, Khorasan-e-Razavi Province (Northeast Iran). First, a discrete wavelet transform (DWT) was applied to the pH, OC, and clay as the inputs and their subcomponents were utilized in the applied data-driven techniques. Statistical Gamma test was also used for identifying which effective soil parameter is able to influence soil P. The applied methods were assessed through 10-fold cross-validation scenarios. Our results demonstrated that the wavelet–GEP (WGEP) model outperformed the other models with respect to various validations, such as correlation coefficient (R), scatter index (SI), and Nash–Sutcliffe coefficient (NS) criteria. The GEP model improved the accuracy of the MARS, RF, SVM, and NN models with respect to SI-NS (By comparing the SI values of the GEP model with other models namely MARS, RF, SVM, and NN, the outputs of GEP showed more accuracy by 35%, 30%, 40%, 50%, respectively. Similarly, the results of the GEP outperformed the other models by 3.1%, 2.3%, 4.3%, and 7.6%, comparing their NS values.) by 35%-3.1%, 30%-2.3%, 40%-4.3%, and 50%-7.6%, respectively.

Polymeric materials as anion-exchange membranes for alkaline fuel cells

2011 ◽  
Vol 36 (11) ◽  
pp. 1521-1557 ◽  
Author(s):  
Guillaume Couture ◽  
Ali Alaaeddine ◽  
Frédéric Boschet ◽  
Bruno Ameduri
Keyword(s):  
Fuel Cells ◽  
Anion Exchange ◽  
Polymeric Materials ◽  
Anion Exchange Membranes ◽  
Alkaline Fuel Cells

scholarly journals Innovative BPPO Anion Exchange Membranes Formulation Using Diffusion Dialysis-Enhanced Acid Regeneration System

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 311
Author(s):  
Muhammad Imran Khan ◽  
Majeda Khraisheh ◽  
Fares AlMomani
Keyword(s):  
Anion Exchange ◽  
Room Temperature ◽  
Feed Solution ◽  
Exchange Capacity ◽  
Anion Exchange Membranes ◽  
Regeneration System ◽  
Waste Streams ◽  
Acid Recovery ◽  
Aqueous Waste ◽  
Diffusion Dialysis

Recycling of acid from aqueous waste streams is crucial not only from the environmental point of view but also for maturing the feasible method (diffusion dialysis). Anion exchange membrane (AEM)–based diffusion dialysis process is one of the beneficial ways to recover acid from aqueous waste streams. In this article, the synthesis of a series of brominated poly (2, 6–dimethyl-1, 4–phenylene oxide) (BPPO)-based anion exchange membranes (AEMs) through quaternization with triphenylphosphine (TPP) were reported for acid recovery via diffusion dialysis process. The successful synthesis of the prepared membranes was confirmed by Fourier transform infrared (FTIR) spectroscopy. The as-synthesized anion exchange membranes represented water uptake (WR) of 44 to 66%, ion exchange capacity of (IEC) of 1.22 to 1.86 mmol/g, and linear swelling ratio (LSR) of 8 to 20%. They exhibited excellent thermal, mechanical, and acid stability. They showed homogeneous morphology. The acid recovery performance of the synthesized AEMs was investigated in a two compartment stack using simulated mixture of HCl and FeCl2 as feed solution at room temperature. For the synthesized anion exchange membranes TPP–43 to TPP–100, the diffusion dialysis coefficient of acid (UH+) was in the range of 6.7 to 26.3 (10−3 m/h) whereas separation factor (S) was in the range of 27 to 49 at 25 °C. Obtained results revealed that diffusion dialysis performance of the synthesized AEMs was higher than the commercial membrane DF–120B (UH+ = 0.004 m/h, S = 24.3) at room temperature. It showed that the prepared AEMs here could be excellent candidates for the diffusion dialysis process.

Sign in / Sign up

Export Citation Format

Share Document