摘要:

Certain soils in the Lower Atlantic Coastal Plain are Mn‐deficient and because of their inherent properties, deficiencies of other elements might be expected. The response of soybean [Glycine max(L.) Merr. cv. ‘Ransom'] to annual soil applications of B, Cu, Fe, Mo, S, and Zn with and without Mn was examined. The study was conducted on an Olustee‐Leefield sand (Ultic Haplaquod‐Arenic Plinthaquic Paleudult) in 1975, 1976, and 1977. Seed yields, and soil and plant tissue concentrations of certain of the applied elements were determined. Soil pH increased from 6.4 in 1975 to 7.0 in 1977 as a result of lime applications.

ISSN:0010-3624    

DOI:10.1080/00103628309367439

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Four extractants, DTPA, EDTA, IN NH4OAc and 0.1N HCl were evaluated on the basis of their ability to predict Zn and Cu deficiencies using nine Saskatchewan soils and alfalfa as a test crop. The DTPA test was found to be most suitable as an index of Zn deficient soils with a “critical”; value for Zn deficiency of 1.1 μg/g of soil. Although the results obtained for Cu were inconclusive, preference of the DTPA test is given for routine analyses. The approximate “critical”; level in the latter case is 0.5 μg/g of soil.

ISSN:0010-3624    

DOI:10.1080/00103628309367440

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Field studies tested the validity of averaging soil test results from producer‐submitted soil samples for estimating the fertility status of a county or geographical region. Fields currently in crop production were selected and sampled randomly to provide sampling intensities similar to those of producers. Two counties (Todd and Graves), each in a differing soils area, were sampled. In Graves County, with similar soils and cropping system throughout, average soil test values from randomly collected samples were nearly the same as those collected from producer‐submitted samples. In Todd County, with two differing soil regions and their associated cropping characteristics, average soil test values for farmer‐submitted samples were slightly more acid and considerably lower in extractable phosphorus and potassium in comparison with values for randomly collected samples.

ISSN:0010-3624    

DOI:10.1080/00103628309367441

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Soil tests are used to predict fertilizer and liming needs of legumes being introduced into permanent pastures. However, the routine drying of soil samples may change the soil characteristics so much that recommendations based on test results may be poorly related to actual plant needs in the field.

ISSN:0010-3624    

DOI:10.1080/00103628309367442

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

This study was conducted to determine iron (Fe) contamination on supposedly clean laboratory glassware used for Fe determinations. Iron adhered tenaciously to glassware that had been well washed and rinsed by usual methods (detergent, HCl, and distilled water) and was removed only by washing the glassware with a Fe che‐lating agent. Variability sometimes noted in Fe determinations could possibly be attributed to Fe contamination on glassware. Our data showed that glassware previously exposed to Fe solutions should be washed with an appropriate Fe chelating agent before subsequent determinations of Fe.

ISSN:0010-3624    

DOI:10.1080/00103628309367443

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A method is presented which allows rapid nitrate analyses of water and waste water samples and soil extracts. The linear working range is typically 0.5–30 mg NO−3‐N/liter and duplicate analysis of samples and standards routinely produces confidence limits for the regression estimate of ‐ ±0.1 mg NO−3‐N/liter at the 95% confidence level. Nitrite, formaldehyde and soluble Iron, as Fe3+, cause a positive Interference, while chloride causes a negative interference. The extent of the Interference is a function of the amount of nitrate present.

ISSN:0010-3624    

DOI:10.1080/00103628309367444

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

For a range of northern N.S.W. forest soils typical of Australian east coast forests, both inorganic and organic P have been determined on sequential soil extracts. Organic P was present in each extract, and in most extracts was a high proportion of the total P, regardless of soil type. Using the sum of the P concentrations in the most neutral extracts as an index of available P, the organic component ranged from 352 to 88% of the total available P. Soil parent material appeared to exert the strongest influence on both soil total P andonthe proportion of organic P/total P which ranged from 26% to 81%. The results have been discussed in relation to soluble organic P and its availability in forest ecosystems. The soil organic P results have been discussed in relation to P availability and supply within the forest ecosystem.

ISSN:0010-3624    

DOI:10.1080/00103628309367445

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The interaction of gamma‐irradiated sewage sludge, nitrogen and phosphorus fertilizers on dry matter production, phosphorus concentration and phosphorus uptake of sorghum was examined. Three crops of sorghum were grown in the greenhouse in 19 1 plastic buckets. The phosphorus and sludge treatments were applied at the initiation of the experiment only. Nitrogen was applied to the corresponding nitrogen treatment pots before each of the three croppings.

ISSN:0010-3624    

DOI:10.1080/00103628309367446

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Nitrogen concentrations were significantly higher in walnut leaves from trees planted with autumn‐olive than in leaves from walnut planted alone, while the reverse was true for potassium. The amount of nitrogen, phosphorus, potassium, calcium, and magnesium based on leaf weight was higher in leaves from walnut trees mixed with autumn‐olive than in leaves from walnut planted alone. The differences in nutrient content between the mixture and walnut alone increased over the sampling period as leaf weights increased proportionately more in the mixture. The increased mobilization of minerals into the leaf is attributed to the increased availability of nitrogen fixed by autumn‐olive and the subsequent uptake by walnut in the mixture. The better nutrition of trees in the mixture compared to walnut planted alone has resulted in better growth and a longer growth period.

ISSN:0010-3624    

DOI:10.1080/00103628309367447

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0010-3624    

DOI:10.1080/00103628309367438

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor