Factors affecting N immobilisation/mineralisation kinetics for cellulose-, glucose- and straw-amended sandy soils

2002 ◽  
Vol 36 (3) ◽  
pp. 190-199 ◽  
Author(s):  
Andrew Vinten ◽  
Whitmore A. ◽  
Bloem J. ◽  
Howard R. ◽  
Wright F.
Keyword(s):  
Sandy Soils ◽  
Factors Affecting ◽  
N Immobilisation

scholarly journals A Contribution to the Study of Factors affecting the Quality and Composition of Potatoes

1905 ◽  
Vol 1 (3) ◽  
pp. 347-357 ◽  
Author(s):  
S. F. Ashby
Keyword(s):  
Sandy Soils ◽  
Factors Affecting ◽  
Different Types

The work was undertaken with the hope of establishing some connexion between the characters of soils as shown by chemical and mechanical analyses, and the quality and composition of the potatoes grown on them. As regards quality, most attention has been given to the occurrence of ‘blackening’ after cooking, especially after a second warming up, and an attempt has been made to get at the cause of this phenomenon. This defect has been often complained of by potato growers and dealers, and seriously affects the price of samples marketed for consumption in towns where the largest buyers are hotels and restaurants which demand a potato capable of keeping its colour after a second steaming. ‘Blackening’ is often associated with sandy soils heavily manured with farmyard dung or town manure, and it has been observed in tubers grown with spring dressings of kainite; concordant opinions, however, are not to be had from practical men, and in fact the defect may arise on the most widely different types of soil. In order to exclude disturbances due to variety, ‘Up to Date,’ as one of the most widely grown sorts, has alone been investigated.

Factors affecting the retention of phosphorus applied as superphosphate to the sandy soils in south-eastern South Australia

Soil Research ◽  
1981 ◽  
Vol 19 (2) ◽  
pp. 167 ◽  
Author(s):  
DC Lewis ◽  
AL Clarke ◽  
WB Hall
Keyword(s):  
Organic Carbon ◽  
South Australia ◽  
Sandy Soils ◽  
Soil Parameters ◽  
Phosphorus Retention ◽  
Phosphorus Sorption ◽  
Leaching Losses ◽  
Factors Affecting ◽  
South Eastern ◽  
Active Iron

The retention of phosphorus applied as superphosphate was measured in 31 multi-rate experiments on siliceous sands in the south-east of South Australia. The amount of phosphorus retained in the top 30 cm of soil and recovered in harvested pasture 5 months after application ranged from 0 to 100% and averaged 57% for an average dressing of 32 kg phosphorus ha-1. Of the eight soil parameters measured, 'active' iron, 'active' aluminium, organic carbon and phosphorus sorption were most closely correlated with phosphorus retention. Combinations of these variables accounted for far more of the variation than did single factors. 'Active' iron and organic carbon accounted for 53.6% of the variation. The inclusion of quadratic 'active' iron and aluminium terms improved the fit with 63.9% of the variation accounted for. Rainfall during the experiments varied from 168 to 484 mm but had no effect on retention. Some agronomic implications of the leaching losses are discussed. It is considered that a measure of 'active' iron and organic carbon could be used as indicators of leaching and could assist in determining phosphorus recommendations in the region.

Field studies on the magnesium, copper and zinc nutrition of maize

1976 ◽  
Vol 86 (1) ◽  
pp. 93-101 ◽  
Author(s):  
B. J. Alloway
Keyword(s):  
Zinc Deficiency ◽  
Potential Problem ◽  
Sandy Soils ◽  
Field Studies ◽  
Factors Affecting ◽  
Extraction Procedures ◽  
Copper And Zinc ◽  
Maize Leaves ◽  
Zinc Nutrition ◽  
Available Zinc

SUMMARYSoils from 55 maize fields in southern and eastern England were tested for available zinc, copper, magnesium and potassium by routine extraction procedures. A high proportion (64%) of the samples contained less than the recommended 50 mg/kg available magnesium, and 24% were within the deficiency range (< 25 mg/kg) for this element. Fewer sites were deficient in copper (7%) and zinc (5%) and these were mainly sandy soils or loams developed on Clay-with-Flints over Chalk. Zinc deficiency in maize does not appear to be a serious potential problem in Britain even though it occurs frequently in other countries, including parts of France.A field of maize with growth problems of varying severity was studied in detail and the available magnesium concentrations found to correlate most closely with the degree of stunting. Soils with healthy plants differed from those in stunted patches of the crop by having higher extractable magnesium, copper and potassium contents. In general the composition of the maize leaves tended to reflect the supply status of the soil, except in the case of chlorotic plants.The influence of factors affecting the availability of the elements investigated and the significance of marginal deficiencies of magnesium and micronutrients in maize are discussed.

scholarly journals Influence of Soil and Nutrient Management on Growth and Quality of Collards

2005 ◽  
Vol 15 (1) ◽  
pp. 163-168
Author(s):  
R.S. Mylavarapu ◽  
J.P. Smith ◽  
F. Munoz
Keyword(s):  
High Temperature ◽  
Nutrient Management ◽  
Sandy Soils ◽  
Nutrient Content ◽  
Conventional Tillage ◽  
Nutrient Supply ◽  
Harvest Time ◽  
Regression Analyses ◽  
Factors Affecting

High temperature and humidity during summer months in the southeastern U.S., in addition to crop nutritional status, are suggested to be the primary reasons for tipburn incidence in collards (Brassica oleracea Acephala Group) adversely affecting their marketability. A 2-year study was conducted to evaluate the efficiency of grower's standard practice (GSP), GSP + gypsum, and a programmed-release fertilizer (PRF) under conventional and deep tillage on collard yield and tipburn incidence. Subsoiling significantly increased yield over conventional tillage. Nutrient supply through PRF did not increase the yields; however, it resulted in either similar or higher levels of macro- and micronutrient levels both in soils and collard tissue compared to GSP and GSP + gypsum treatments. The occurrence of tipburn in collards is dependent on several factors, including nutritional, physiological, and environmental stresses. Regression analyses of tipburn ratings at harvest time and the soil and tissue nutrient content suggested that 47% of the variation could be attributed to soil and tissue levels of sulfur (S), zinc (Zn), and phosphorus (P). It is important, therefore, to ensure an optimum supply of nutrients to the plants to maintain the quality of the yields. The advantage of PRF in sandy soils, and identification of other factors affecting the tipburn in collards should be further investigated.

Edaphic Factors Affecting the Activity of Terbutryn

Weed Science ◽  
1972 ◽  
Vol 20 (1) ◽  
pp. 28-30 ◽  
Author(s):  
L. F. Figuerola ◽  
W. R. Furtick
Keyword(s):  
Winter Wheat ◽  
Soil Temperature ◽  
Water Content ◽  
Root System ◽  
Sandy Soils ◽  
Field Capacity ◽  
Edaphic Factors ◽  
Factors Affecting ◽  
High Soil ◽  
High Soil Temperature

Injury from 2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine (terbutryn) was greater on winter wheat(Triticum aestivunVill. ‘Host’) grown at high soil temperature than on that grown at low soil temperature. The injury was more severe when the herbicide was incorporated into the soil close to the root system. In postemergence applications 2-week-old plants were more susceptible to terbutryn injury than 4-week-old plants. High soil water content (75% to 100% of field capacity) favored the uptake of terbutryn through the root system. Terbutryn caused greatest damage under high transpiration rates and in sandy soils.

scholarly journals Character of Soil Cover and State of Land Use Fund in the Absheron Region

2020 ◽  
Vol 6 (4) ◽  
pp. 173-180
Author(s):  
S. Ganiyeva
Keyword(s):  
Land Use ◽  
Soil Profile ◽  
Soil Cover ◽  
Ecological Factors ◽  
Sandy Soils ◽  
Factors Affecting ◽  
Administrative Region ◽  
Physico Chemical ◽  
Chemical Characters ◽  
Morphogenetic Analysis

The morphogenetic analysis of the soils in Absheron administrative region was analyzed, the peculiarity of the ecological factors affecting the formation of physical, physico–chemical characters was given. The composition of soil fund is analyzed. An area of clayey, heavy, average, light clayey, sandy soils was calculated. Land grouping was performed for soil profile density. The analysis was performed on administrative–zone units of the areas in the agricultural places (tillage, perennial planting, pastures and hay field), the distribution legislation of the land property forms was studied.

Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

1977 ◽  
Vol 35 ◽  
pp. 214-217
Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly
Keyword(s):  
Image Analysis ◽  
Image Quality ◽  
Exposure Time ◽  
Image Contrast ◽  
Automated Image Analysis ◽  
Practical Application ◽  
Factors Affecting ◽  
High Image Quality ◽  
Qualitative Evidence ◽  
Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

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