scholarly journals Concentration and vertical distribution of total soil phosphorus in relation to time of abandonment of arable fields

2007 ◽  
Vol 79 (1) ◽  
pp. 73-79 ◽  
Author(s):  
A. van der Wal ◽  
W. de Boer ◽  
I. M. Lubbers ◽  
J. A. van Veen
Keyword(s):  
Vertical Distribution ◽  
Soil Phosphorus ◽  
Total Soil ◽  
Arable Fields ◽  
Total Soil Phosphorus

Prediction of yield responses to phosphorus by established Greenleaf desmodium/grass pastures in south-east Queensland using chemical tests

1980 ◽  
Vol 20 (105) ◽  
pp. 477
Author(s):  
GE Rayment ◽  
RC Bruce ◽  
BG Cook
Keyword(s):  
Soil Phosphorus ◽  
Residual Variance ◽  
Total Soil ◽  
Plant Chemical ◽  
Diagnostic Samples ◽  
Total Soil Phosphorus ◽  
Independent Variable ◽  
Phosphorus Status ◽  
Yield Responses ◽  
Phosphorus Levels

Phosphorus topdressing experiments (rates to 60 kg P ha-1) on 18 commercial Desmodium intortum cv. Greenleaf/grass pastures were conducted over a 4-year period in south-east Queensland. The aim was to determine whether yield responses, which occurred only in the Greenleaf component at six sites, could be predicted using soil or plant chemical tests. Acid-(0.005 M H2SO4) and bicarbonate-(0.5 M NaHCO3) extractable tests of phosphorus status in 0-10 cm soil samples each explained about 60% of the variance in Greenleaf relative yields. The residual variance was not significantly reduced by the inclusion of terms for total soil nitrogen, total soil phosphorus, exchangeable calcium and pH into the independent variable. These empirical soil phosphorus tests had higher predictive value than plant tests based on phosphorus concentrations in tops and diagnostic samples of Greenleaf. With both acid- and bicarbonate-extractable phosphorus, yield responses are likely in the Greenleaf component when phosphorus levels in most soils are below 22 ppm. Above 29 ppm, no response would be expected

scholarly journals Impact of Plant Invasion and Increasing Floods on Total Soil Phosphorus and its Fractions in the Minjiang River Estuarine Wetlands, China

Wetlands ◽  
2015 ◽  
Vol 36 (1) ◽  
pp. 21-36 ◽  
Author(s):  
Wei-Qi Wang ◽  
Jordi Sardans ◽  
Cong-Sheng Zeng ◽  
Chuan Tong ◽  
Chun Wang ◽  
...  
Keyword(s):  
Plant Invasion ◽  
Soil Phosphorus ◽  
Estuarine Wetlands ◽  
Minjiang River ◽  
Total Soil ◽  
Total Soil Phosphorus ◽  
River Estuarine

An attempted fractionation of the soil phosphorus

1938 ◽  
Vol 28 (2) ◽  
pp. 234-246 ◽  
Author(s):  
L. A. Dean
Keyword(s):  
Sodium Hydroxide ◽  
Organic Phosphorus ◽  
Soil Phosphorus ◽  
Inorganic Phosphorus ◽  
Soil Extracts ◽  
Soil Calcium ◽  
Soluble Phosphorus ◽  
Total Soil Phosphorus ◽  
Continued Use ◽  
Phosphatic Fertilizers

1. Extractions of soils with sodium hydroxide, followed by an acid, have been used in an attempt to fractionate the soil phosphorus.2. Colorimetric methods for the estimation of the organic and inorganic phosphorus in alkali soil extracts have been suggested.3. The amount of soil phosphorus soluble in sodium hydroxide is affected by the active soil calcium. It is suggested that sodium-saturated soils be used when studying the alkali-soluble phosphorus.4. The acid-soluble phosphorus remaining in soil after extraction with sodium hydroxide was determined. This fraction appears by analogy to be similar to the apatites.5. The largest fraction of the total soil phosphorus was not dissolved by the sodium hydroxide and acid extractions. This fraction was not increased by the long-continued use of phosphatic fertilizers at Rothamsted and Woburn.6. Relatively large amounts of organic phosphorus were found in soils and the amounts were closely related to the carbon contents.

PHOSPHORUS FRACTIONS IN A SOIL SAMPLED AT DIFFERENT DEPTHS AND THE EFFECT OF LIME AND FERTILIZER ON OATS AND CLOVER IN A GREENHOUSE TEST

1960 ◽  
Vol 40 (1) ◽  
pp. 71-79
Author(s):  
H. A. Hamilton ◽  
J. R. Lessard
Keyword(s):  
Surface Soil ◽  
Crop Yields ◽  
Organic Phosphorus ◽  
Soil Phosphorus ◽  
Phosphate Fertilizer ◽  
Iron Phosphate ◽  
Soil Layers ◽  
Surface Samples ◽  
Different Depths ◽  
Total Soil Phosphorus

Soil samples were collected at four different depths from a virgin soil, and in a region where deep ploughing has been a common practice. Chemical analyses revealed that the sub-surface samples were more highly saturated with bases than were the surface samples. In the 0–6 inch layer the percentage contribution of calcium, aluminium and iron phosphate to total soil phosphorus was 41.1, 10.4 and 2.8 respectively; while, in the 18–24 inch layer the percentages were 88.4, 2.8 and 0.5 respectively. Organic phosphorus decreased with depth.In the greenhouse there were highly significant differences between oat yields on the various layers, the surface soil giving the highest yields. Clover crop yields tended to be better as depth of profile increased. Phosphorus increased oat yields and clover yields on all soil layers. As a result of over-liming in certain instances clover yields were depressed in the absence of applied phosphate fertilizer, whereas oat yields were unaffected.

Accumulation of plant nutrients and changes in soil properties of sandy soils under fertilized pasture in southeastern South-Australia .I. Phosphorus

Soil Research ◽  
1987 ◽  
Vol 25 (2) ◽  
pp. 193 ◽  
Author(s):  
DC Lewis ◽  
AL Clarke ◽  
WB Hall
Keyword(s):  
Organic Phosphorus ◽  
Soil Phosphorus ◽  
Balance Sheet ◽  
South Australia ◽  
Single Superphosphate ◽  
Phosphorus Accumulation ◽  
Total Soil Phosphorus ◽  
Clay Layers ◽  
Stocking Rates ◽  
Phosphorus Levels

The accumulation of phosphorus applied as superphosphate over a 25-year period to pastures growing on sand over clay soils was measured in three areas of different rainfall in the south-east of South Australia. Total soil phosphorus levels increased in the 0-10 cm, 10-30 cm and 30 cm-clay layers for all areas, but no accumulation occurred in the clay layer. For every 100 kg ha-1 of single superphosphate (9.6% phosphorus) applied, 2.0, 3.2 and 3.5 kg ha-1 of phosphorus accumulated in the 0-10 cm layer for the Hundreds of Coles, Willalooka and Senior respectively. The recoveries of applied phosphorus in the sand layer for the three areas were 42, 57 and 75% for Coles, Willalooka and Senior respectively. The annual accumulation rates of organic phosphorus in the top 30 cm of soil ranged from 2.4 to 3.5 kg ha-1. By using a 'balance sheet' approach, the annual maintenance phosphate requirements for the three areas were calculated. These ranged from 60 to 165 kg ha-1 of superphosphate, and were associated with differences in leaching losses, stocking rates and organic phosphorus accumulation.

INFLUENCE OF TEXTURE AND MANAGEMENT PRACTICES ON THE FORMS AND DISTRIBUTION OF SOIL PHOSPHORUS

1987 ◽  
Vol 67 (1) ◽  
pp. 147-163 ◽  
Author(s):  
J. W. B. STEWART ◽  
I. P. O'HALLORAN ◽  
R. G. KACHANOSKI
Keyword(s):  
Management Practices ◽  
Soil Phosphorus ◽  
Organic P ◽  
Sand Content ◽  
P Fractions ◽  
P Fractionation ◽  
Inorganic P ◽  
Soil P ◽  
Total Soil ◽  
Labile Organic P

Changes in soil phosphorus (P) forms, as determined by a sequential fractionation procedure, were used to assess the influence of soil texture and management practices on the forms and distribution of soil P in a Brown Chernozemic loam soil at Swift Current, Saskatchewan. Significant proportions of the variability of all P fractions except residual-P could be attributed to changes in sand content. Changes in the forms and distribution of soil P with decreasing sand content followed patterns similar to those associated with a weathering sequence. The proportion of total soil P in inorganic and organic extractable forms that were extractable sequentially with anion exchange resin (resin-Pi), sodium bicarbonate (bicarb-Pi and -Po), and sodium hydroxide (NaOH-Pi and -Po) increased with decreasing sand content. Acid-extractable inorganic P (HCl-Pi) was the only P fraction positively correlated with sand content. The presence of a crop increased the proportion of soil P present as the more labile organic-P fractions (bicarb-Po and NaOH-Po) but not as total soil organic P (soil-Po). The presence of a crop also increased the proportion of soil P present as the labile inorganic fractions (resin-Pi and bicarb-Pi), possibly due to a decrease in soil pH. Application of inorganic-P fertilizer caused significant increases in the proportion of soil P as these labile inorganic-P fractions (resin-Pi and bicarb-Pi) and as total soil organic-P (soil-Po), but did not affect the more labile organic-P fractions. Key words: P fractionation, labile P, organic P, inorganic P, texture, management practices

Soil acidification under clover pasture

1980 ◽  
Vol 20 (106) ◽  
pp. 561 ◽  
Author(s):  
CH Williams
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Phosphorus ◽  
Chemical Properties ◽  
Subterranean Clover ◽  
Titratable Acidity ◽  
Exchange Capacity ◽  
Early Years ◽  
Total Soil ◽  
Clover Pasture

Long-term changes in some chemical properties of yellow podzolic soils under subterranean clover pastures were studied near Binda, New South Wales. The rate of decrease in pH of the surface 10 cm of soil was greatest in the early years following pasture establishment, and decreased with time. Over 50 years the decrease in pH was approximately one unit, resulting in current soil pH values of about 5.0. The increased acidity had led to increases in CaCI,-extractable manganese and exchangeable aluminium. Although the build-up of soil organic matter under a 32- year-old subterranean clover pasture was largely confined to the surface 10 cm, the decrease in pH extended to a depth in excess of 30 cm. Total soil nitrogen increased gradually throughout the 50-year period, reflecting increases in the soil organic matter. There were associated increases in cation exchange capacity and titratable acidity. Total soil phosphorus also increased with time and was correlated with the decrease in pH. This reflected the accumulation of organic and inorganic residues from phosphate fertilizers, but it seems unlikely that the acidity of the superphosphate contributed directly to the increase in soil acidity although it is essential for the establishment and maintenance of the legume, the main source of the increase in soil organic matter. It seems likely that the area of pasture soils adversely affected by acidity problems will increase in the future.

Sign in / Sign up

Export Citation Format

Share Document