摘要:

Three types of sewage sludge are applied to the surface of soil columns of Coastal Plain soils and leached with distilled water. The Zn concentrations in leachate samples from a Sassafras loamy sand soil loaded with an industrial sludge increased with sludge loading rate. All leachate samples contained very low concentrations of Cd, Cr and Cu. Hazardous amounts of Cd, Cr, Cu and Zn would not be leached to the groundwater when recommended rates of the tested sludges are applied to Coastal Plain soils under most conditions.

ISSN:0010-3624    

DOI:10.1080/00103627809366853

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Sludge was applied to a Matapeake silt loam soil at loading rates of 0, 22, 45 and 90 mt/ha where corn and soybeans were planted. Corn seedling, ear leaf, grain and stover, and soybean seedling and grain samples were analyzed for their Al, B, Ba, Cu, Fe, Mn, Na, Sr and Zn. Corn grain and stover and soybean grain samples were analyzed for As, Cd, Cr, Hg and Pb. Normal concentrations of As, Cd, Cr, and Hg were found in the corn grain and stover and soybean grain. The Pb concentration in the corn stover increased with increased sludge application rates. The Al, Ba and Fe concentrations decreased in the corn seedling samples at the 45 and 90 mt/ha loading rates but all trace element concentrations in the corn ear leaf tissue were within the normal range for corn.

ISSN:0010-3624    

DOI:10.1080/00103627809366854

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Pot experiments were conducted to determine effects of applied N on NO3‐N and total N concentrations in Swiss chard (Beta vulgarisvar. cicla) and of applied N, P, and K on Bloomsdale spinach(Spinacia oleraceaL.) and on curly mustard (Brassica pervirdisL.). Ammonium nitrate produced greater increases in NO3‐N and total N concentrations in chard than did sulfur‐coated urea at the same rates of applied N. Both N and K increased yields and NO3‐N accumulation in spinach and mustard; response to applied P resulted only in decreased NO3‐N. Both total and NO3‐N concentrations decreased with dilution and/or assimilation associated with time of growth and higher yields.

ISSN:0010-3624    

DOI:10.1080/00103627809366855

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Six greenhouse pot experiments were conducted in which yield and nutrient uptake responses of corn(Zea maysL.) or tall fescue(Festuca arundinaceaShreb) to N, P, K, lime, or temperature variables were measured. This paper describes yield—NO3‐N and total N concentration trends in these experiments. Crop concentrations of total N and NO3‐N during early growth increased consistently with amount of applied N. These concentrations usually decreased (by dilution and assimilation) with time of growth and yield response to other growth‐limiting nutrients and other factors. Concentrations of K also increased in corn with amount of applied K, and high K was associated with higher concentrations of NO3‐N during early growth in some experiments. This was usually true only for early crop growth periods during which rates of nutrient uptake exceeded growth rate. High K concentrations may have retarded growth and NO3‐N reduction and assimilation.

ISSN:0010-3624    

DOI:10.1080/00103627809366856

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Environmental effects onSedum rubrotinctum, R. T. Clausen grown for at least 6 months in environmental condition that induce diurnal acid fluctuation (IN CAM) or prevent acid fluctuation (OUT OF CAM) exhibit certain metabolic changes which were studied. Change in photo‐period alone caused the greatest amplitude of the acid fluctuation from 13.8 to 2.0 meq acid/100 g FW. The total δ13C values within a 24 hr period when IN CAM varied from ‐12.2 to ‐22.1%Ocompared to OUT OF CAM from ‐18.3 to ‐20.4%o. Isotope analysis proved a useful technique to study environmental effects and hourly shifting metabolic patterns of CAM plant.

ISSN:0010-3624    

DOI:10.1080/00103627809366857

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

For characterizing the rate of increase of the available soil phosphorus content applying superphosphate fertilization the slope of the linear regression curve in the range of 0–12–120 ppm P is used. The available phosphorus is determined by NH4‐lactate and NaHCO3extractions. The rate of increase of available phosphorus is primarily influenced by the presence of CaCO3and is in close correlation with the pH, as well as the silt + clay content. The rate of decrease of available phosphorus in time after P fertilization in non‐calcareous soil is similar, in calcareous soil is different measured by the two extractions.

ISSN:0010-3624    

DOI:10.1080/00103627809366858

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Discharge tubes containing argon, and NH3separated from atmospheric N2by condensation in a liquid‐nitrogen—cooled trap, are used to determine15N:14N ratios in ammonium solutions. Reduction of NH3to N2during sample preparation is not required; the dissociation of NH3in the discharge tube produces sufficiently intense N2band spectra for the isotope analysis. The method can be readily applied to the analysis of ammonium solutions derived from Kjeldahl digests of plant material.

ISSN:0010-3624    

DOI:10.1080/00103627809366859

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A refined scheme for the semi micro chemical analysis of sulfur fractions in soils is presented. Pyrite is analyzed, as iron, after extraction in HNO3. Non‐pyrite iron is excluded by a pretreatment with HF/H2SO4. Water‐soluble sulfate and jarosite [KFe3(SO4)2(OH)6], the other dominant sulfur fractions in acid sulfate soils, are analyzed turbidimetrically, as sulfate, after successive extractions by EDTA.3Na (water soluble plus exchangeable SO4) and by hot 4 M HCl (jarosite). These methods are simpler, less bulky and more specific than most existing procedures.

ISSN:0010-3624    

DOI:10.1080/00103627809366860

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Five levels of S (as gypsum) were topdressed on to a pasture containing subterranean clover. Yield responses by the clover fraction of the pasture were measured, together with the total S concentration, the sulphate S concentration and the N:S ratio in young clover plants collected in autumn prior to the fertilizer application, and in plants from the control plots collected in winter and in spring.

ISSN:0010-3624    

DOI:10.1080/00103627809366861

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Molybdenum applications had no effect on the grain yield of wheat or barley. Application of limestone increased barley yield at one of the three locations and had no effect on wheat yield at any location. The Mo concentration of boot stage tissue increased with added Mo. In most cases, 0.56 kg Mo/ha applications increased the Mo concentration of boot stage tissue above 10 ppm. Increases in Mo concentration due to added Mo were generally greater at higher rates of limestone application but the Mo x limestone interaction was statistically significant only for barley at the location having the lowest pH and for wheat at the two locations with the lowest pH. Molybdenum applied as a foliar spray was found to be an effective means of increasing the Mo concentration of cereal tissues. In the case of suspected Mo deficiency in cereals, a foliar application of 0.28 kg Mo/ha should correct the problem without any ill effect from an animal nutrition standpoint.

ISSN:0010-3624    

DOI:10.1080/00103627809366862

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor