摘要:

AbstractAn apparatus has been devised, based on the work of Audus, for circulating under controlled conditions various types of liquor and solutions of ammonium salts of equivalent strength over duplicate samples of various soils. At regular intervals analyses were made to determine the progress of the nitrification and also the concentration of thiocyanate and phenols. Work over a period of several years showed that in the case of the soils examined nitrification proceeded satisfactorily and that within about a quarter of the time required for nitrification the thiocyanate and phenols had disappeared.This is in keeping with the results of plot trials and leads to the general conclusion that, when clean ammoniacal liquor is used as a fertiliser applied directly to the ground, there is no build‐up of toxic substances in the soil, from the point of view of nitrificatio

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100401

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractRecent experiments by Russian workers, using peat as a composting agent to solubilise phosphate rock, have been repeated with Irish peat and Algerian phosphate rock. The rock had 29.3% total P2O5of which 0.2% (0.7% of the total) was soluble in citric acid. This percentage citric solubility increased to 3.3 and 7.2, respectively, in composted 6 to 1 and 10 to 1 mixtures of peat and rock.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100402

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractVarious layers from profiles from upland acid peat area containing both untouched and reclaimed sites were chemically examined for inorganic and organic changes as a result of treatments. Low phosphorus and high aluminium and lead contents were found and a layer of copper accumulation was noted in the undisturbed site. Lanthanum content was also found to be high. The amino‐acid distribution in hydrolysates of soil water, as well as pyrophosphate‐extracted humic acid and the pyrophosphate‐insoluble soil residue containing organic matter, was examined. The surface layers are characterised by the presence of non‐protein amino‐acids of plant and microbiological origin. The basic amino‐acids appeared to be in greater strength in the soil water samples from treated sites than those from untreated sites. The soil residue appears to be a reservoir of amino‐sugar‐containing compounds. The relative distribution of certain “non‐protein” amino‐acids found in small amounts in the humic acids isolated from samples from different depths in the profile, may possibly be explained if the humic acid is considered as a cation‐exchanger being elu

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100403

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractA new method for rapid and precise determination of soil nitrates is described, based on quantitative reduction of nitrate to nitrite, followed by colorimetric estimation of an azo dye (Orange I). The method is sensitive to 0.006 p.p.m. of nitrate nitrogen in solution and with a dilution technique the accuracy has been tested over a range of 0.05–40 p.p.m. in soil. A means of correcting for interference from soil extracts is also discussed.For certain soils of Northern Nigeria, the method is more rapid, and for very small amounts of nitrate considerably more accurate than the phenolsulphonic acid method. Statistical examination of the data shows that the two methods yield results of closely similar agronomic significance, but the Orange I method gives values with greater precisio

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100404

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractUsing the methods described in Part I, an experimental study was made of the changes in composition and of the losses of organic matter and nitrogen from deep litter in a manner similar to the study made on composts and described in Part II.Over a period of 11 months, losses of organic matter and of nitrogen by decomposition were approx. 50 and 40%, respectively. Results indicated that deep litter should be moistened before storage to prevent escape of ammonia and encourage formation of nitrate.Indirect calculations of the losses of organic matter and nitrogen throughout the experimental period were made from the changes in the ratios of each to the ash, the phosphorus and the potassium contents, assuming that these three components of the straw and droppings accumulated in the litter without loss.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100405

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractResults of previous manurial trials with poultry droppings and bulky organic manures are reviewed in relation to experiments designed to compare the manurial values of fresh droppings, composts prepared from straw and droppings, and of deep litter, with ammonium sulphate as a standard nitrogen fertiliser.A pot trial with spinach beet and two field trials with potatoes were conducted using adequate basal quantities of phosphate and potassium in order to test the availability of the nitrogen in the organic manures. In the pot trial and in one of the field trials during a wet season, good agreement was obtained between the amount of nitrogen soluble in cold o.IN‐sulphuric acid and crop responses, but in the second field trial in a dry season, very different results were obtained.Deep litter has several advantages over composts: thus it affords a more economical means of absorbing droppings, it is more concentrated in organic matter and it requires only half the weight to provide the same quantity of dry matter. Under moist soil conditions, half the total nitrogen in fresh droppings and deep litter may be equivalent to ammonium sulphate, but the proportion in composts depends on the initial composition and state of maturity of the compost.Suggestions are made for further work, particularly with large heaps stored under cover for one to three year

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100406

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe complete amino‐acid compositions of the flesh of four common British food fishes have been determined. Only slight differences were found. The results are compared with other published work on the same and different specie

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100407

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractStudies are made of the effects of the following factors influencing the free acidity of the fat of P.spinulosum: (1) sterilisation of the felts in their metabolism solutions and when floated on distilled water; (2) the initial pH value of the medium; (3) addition of calcium carbonate to stabilise the pH of the medium at near neutrality during incubation; (4) the presence of glycerol as well as glucose in the medium; (5) addition of sodium sulphite. The results are discussed in relation to the metabolic processes of the mould.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100408

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

摘要:

AbstractThe water absorptions of flour from 23 samples of two wheat varieties, Atle and Hybrid 46, have been measured. Comparison of the results with estimates of flour‐nitrogen and damaged starch content, indicate that differences in absorption are largely accounted for by variation in these factors. The evidence also confirms previous suggestions that more starch damage occurs in the milling of “hard” than “soft” wheats and that in “hard” wheats starch damage is likely to increase with the protein content

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100409

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740100410

出版商:John Wiley&Sons, Ltd    

年代:1959

数据来源: WILEY