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

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.

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Evaluation of Serum Zinc Status of Pregnant Women in the China Adult Chronic Disease and Nutrition Surveillance (CACDNS) 2015

Nutrients ◽

10.3390/nu13041375 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1375

Author(s):

Xiao-Bing Liu ◽

Jia-Xi Lu ◽

Li-Juan Wang ◽

Yi-Chun Hu ◽

Rui Wang ◽

...

Keyword(s):

Chronic Disease ◽

Pregnant Women ◽

Zinc Deficiency ◽

Evaluation System ◽

Family Income ◽

Serum Zinc ◽

Zinc Status ◽

National Monitoring ◽

Significant Difference ◽

Zinc Nutrition

Objective: The purpose of this study was to evaluate serum zinc status of pregnant women in the China Adult Chronic Disease and Nutrition Surveillance (CACDNS) in 2015–2016. Methods: A total of 7147 apparently healthy pregnant women were randomly selected in 302 national monitoring sites. Information on age, race, residence region, education, pregnancy, and family income per annum was collected, and the concentration of serum zinc was determined. The evaluation of serum zinc status was further performed according to the recommendations by the International Zinc Nutrition Consultative Group (IZiNCG). Results: The median concentration of serum zinc was 858.9 μg/L with an interquartile range (IQR) of 712.9 μg/L and 1048.9 μg/L, while the overall prevalence of zinc deficiency was 3.5% with a 95% confidence interval (CI) of 3.0% and 3.9%. Serum zinc status of pregnant women changed greatly in the different categories, particular in pregnancy and family income per annum (p < 0.05), but no significant difference was observed in the prevalence of zinc deficiency (p > 0.05). Conclusions: The lower prevalence of zinc deficiency generally indicated a better zinc status for pregnant women in the CACDNS in 2015–2016. However, a well-designed evaluation system of zinc status for pregnant women should be continually optimized and improved by inducing more parameters such as biochemical, dietary, or functional indicators.

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Prediction of leaching and groundwater contamination by pesticides

Pure and Applied Chemistry ◽

10.1351/pac200678051081 ◽

2006 ◽

Vol 78 (5) ◽

pp. 1081-1090 ◽

Cited By ~ 10

Author(s):

Werner Kördel ◽

Michael Klein

Keyword(s):

Maximum Concentration ◽

Management Practices ◽

Preferential Flow ◽

Soil Depth ◽

Sandy Soils ◽

Field Studies ◽

Macropore Flow ◽

Eu Directive ◽

Present Information ◽

Silty Soils

Herein, we describe how pesticide leaching is assessed in Europe in order to fulfill EU Directive 91/414. The assessment schemes were developed to protect groundwater from unacceptable effects caused by pesticide use. They presently focus on chromatographic flow processes, which are dominant in sandy soils. Nevertheless, important regions in Europe are characterized by structured soils where transport through macropores is most relevant.Comparison of parallel field studies with isoproturon performed in sandy and silty soils showed that maximum concentration in the structured soil at a soil depth of 1 m may exceed respective concentrations in sandy soils by a factor of 60. Similar results were obtained by lysimeter studies using silty soil cores with maximum concentration of 40 μg/l at the soil bottom. These results demonstrate that preferential flow is more the rule than the exception in well-structured fine-textured soils, and pesticide losses via macropore flow may exceed losses via matrix transport considerably. All present information available for macropore flow suggest the need for greater regional assessments. Other recommendations include analysis of the influence of different soil management practices on the formation of macropores.

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Factors Affecting Productivity of Refuse Compactor Vehicles in India

The Journal of Solid Waste Technology and Management ◽

10.5276/jswtm/2021.529 ◽

2021 ◽

Vol 47 (3) ◽

pp. 529-535

Author(s):

Khant Shah ◽

Devanshu Pandit

Keyword(s):

Solid Waste Management ◽

Field Studies ◽

Operating Costs ◽

Municipal Solid Waste Management ◽

Critical Factors ◽

Factors Affecting ◽

Operation Optimization ◽

Selection Parameters ◽

Evaluation And Monitoring ◽

Hierarchy Process

Shift towards mechanization in the municipal solid waste management (MSWM) is aimed at improving health wellbeing of the workers who are manually handling waste. With huge investment and operating costs, proper evaluation and monitoring of the performances of these equipment is essential. Identifying and rating the factors which impact the performance of equipment is the first step towards improving efficiency of a system. This research identifies the critical factors and issues in the operation optimization of refuse compactor vehicles. Interviews with experts and field studies helped in identification of 30 factors which were divided in five categories. The research uses analytical hierarchy process (AHP) for finding out the priority vectors of thus identified factors and categories. The study also highlights equipment selection parameters for the best suited model and make.

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Application of immobilized mycelium-based pellets for the removal of organochlorine compounds: a review

Water Science & Technology ◽

10.2166/wst.2021.093 ◽

2021 ◽

Author(s):

J. C. V. Pereira ◽

M. P. Serbent ◽

E. Skoronski

Keyword(s):

Wastewater Treatment Plants ◽

Cost Effective ◽

Field Studies ◽

Organochlorine Compounds ◽

Environmental Persistence ◽

Factors Affecting ◽

Materials Used ◽

Immobilization Techniques ◽

Enzymatic Machinery

Abstract Organochlorines have diverse structures and applications and are included in the list of persistent organic pollutants (POPs) due to their toxicity and environmental persistence. The reduced capacity of conventional wastewater treatment plants to remove these compounds encourages the development of cost-effective and efficient remediation approaches. Fungal biotechnology can contribute to the development of these technologies through their enzymatic machinery but faces several drawbacks related to the use of dispersed mycelium. In this sense, investigations concerning the degradation of organochlorines using immobilized fungi demonstrated an increase in contaminants removal efficiency compared with degradation by free cells. Despite this interest, the mechanisms of immobilized fungi have not been comprehensively reviewed. In this paper, recent advances of laboratory and field studies in organochlorine compounds removal by fungi were reviewed, focusing on the role of immobilization techniques. Firstly, the mechanisms of organochlorines bioconversion by fungi and the factors affecting enzyme activity are elucidated and discussed in detail. Then, the main targeted compounds, fungi, technics, and materials used for immobilization are discussed, as well as their advantages and limitations. Furthermore, critical points for future studies of the fungi immobilization for organochlorines removal are proposed.

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

The Journal of Agricultural Science ◽

10.1017/s0021859600000368 ◽

1905 ◽

Vol 1 (3) ◽

pp. 347-357 ◽

Cited By ~ 10

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.

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Zinc nutrition and salt preference in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1981.241.3.r233 ◽

1981 ◽

Vol 241 (3) ◽

pp. R233-R239 ◽

Cited By ~ 1

Author(s):

W. Jakinovich ◽

D. W. Osborn

Keyword(s):

Sodium Chloride ◽

Zinc Deficiency ◽

Clinical Symptoms ◽

Taste Receptor ◽

Maximum Growth ◽

Central Nervous System Disorder ◽

Receptor Sensitivity ◽

Electrophysiological Responses ◽

Zinc Nutrition ◽

System Disorder

Zinc-deficient rats have an increased preference for sodium chloride (saltwater). We investigated the possibility that this elevated saltwater preference is due to nonfunctional taste receptors. In experiment I, zinc-deficient rats consumed more saltwater than zinc-sufficient rats at most sodium chloride concentrations tested (0.001-1.0 M). When the zinc-deficient rats were fed a zinc-sufficient diet, the clinical symptoms of zinc deficiency rapidly disappeared. However, the rats still preferred saltwater to a greater extent than rats maintained on the zinc-sufficient diet. In experiment II, rats fed diets supplemented with levels of zinc below the requirement for maximum growth had an increased preference for saltwater (0.15 M NaCl). In experiment III, electrophysiological responses of the taste nerves to various concentrations of sodium chloride, sucrose, quinine . HCl, and hydrochloric acid were the same in both zinc-deficient and zinc-sufficient rats. We conclude that the taste receptor sensitivity of the rat is not impaired by zinc deficiency. The increased salt preference of zinc-deficient rats might be related to some endocrine or central nervous system disorder precipitated by inadequate dietary zinc.

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Atrazine Dissipation as Affected by Surface pH and Tillage

Weed Science ◽

10.1017/s0043174500027867 ◽

1980 ◽

Vol 28 (1) ◽

pp. 101-104 ◽

Cited By ~ 28

Author(s):

J. J. Kells ◽

C. E. Rieck ◽

R. L. Blevins ◽

W. M. Muir

Keyword(s):

Weed Control ◽

Soil Ph ◽

Field Studies ◽

Conventional Tillage ◽

Field Conditions ◽

No Tillage ◽

Tillage Systems ◽

Surface Ph ◽

Factors Affecting ◽

Decreasing Ph

Field studies and laboratory analyses were conducted to examine factors affecting degradation of14C-atrazine [2-chloro-4-(ethylamine)-6-(isopropylamino)-s-triazine] under field conditions. The effects of these factors on weed control under no-tillage and conventional tillage systems were also examined. The amount of radioactivity which was unextractable in 90% methanol increased with time following treatment with14C-atrazine. The rate of formation of unextractable14C compounds was greater under no-tillage and increased with decreasing pH. After 14 to 18 days, a greater amount of extractable atrazine was present in areas receiving lime. The degradation of atrazine occurred more rapidly when surface pH was less than 5.0 compared with a pH greater than 6.5. The effect of lime on the amount of parent atrazine present in the soil was directly correlated to its effect on soil pH. Extractable atrazine in the soil 45 days after treatment was significantly correlated with weed control with the greatest effect under no-tillage.

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