Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    European journal of soil science 52 (2001), S. 0 
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: A major concern with the safe re-use of biosolids on land is the potential for release of metals from organic matter in the biosolids, due to decomposition proceeding as biosolids age. To quantify the effects of biosolid aging on Cd and Zn bioavailability, two sewage sludges (Lagoon sludge and Filtered sludge) and a garden compost were incubated at 25°C and 35°C for 100 days. Changes in availability of Cd and Zn were determined using isotope dilution principles, with the materials being labelled with carrier-free 109Cd and 65Zn. We determined isotopically exchangeable metal pools (E values) and plant available metal pools (L values) by measuring specific activities of Cd and Zn in soil extracts and in wheat plants, respectively. Changes in carbon content over time were determined using 13C-NMR spectroscopy and chemical extraction methods, and related to changes in availability of metal pools as determined by isotopic procedures.Hot-water-extractable carbon content, assumed to represent easily decomposable organic matter, decreased during the 100 days by 80–190 mg kg−1. The Compost and Lagoon sludge showed no change in L values for Cd or Zn with time, but in the Filtered sludge the L values for Cd and Zn increased significantly, by 43% and 56%, respectively. The isotopically exchangeable pools of Cd and Zn did not change with incubation treatment of the biosolids.These data indicate that the potential for metal release from biosolids as organic matter decomposes depends to a large extent on the biosolid composition.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science, Ltd
    Plant, cell & environment 26 (2003), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The mobility of Cd in potato plants (Solanum tuberosum) was examined using both short-term radioisotopic labelling with 109Cd and long-term growth experiments in soil supplemented with Cd, with an emphasis on the pathways through which Cd is taken up by tubers. Split-pot experiments showed that tubers and their associated stolons and stolon roots contribute only a minor fraction to the overall Cd absorption by the plant. Most of the Cd was absorbed by the basal roots. 109Cd absorbed from the soil was rapidly exported to other parts of the plant, especially the stem, with significant amounts appearing in the tubers within 30 h. Application of 109Cd to leaves showed that Cd can be rapidly distributed via the phloem to all tissues. The results suggest that unlike Ca, Cd has high mobility in plants in both xylem and phloem, and that stems may have an important role in transfer between these two pathways.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-0867
    Keywords: cultivar ; food regulations ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In some areas of southern Australia, cadmium (Cd) concentrations in excess of the Australian maximum permitted concentration (0.05 mg kg−1 fresh weight) have been found in tubers of commercially grown potato (Solanum tuberosum L.) crops. Field experiments were therefore conducted in various regions of Australia to determine if Cd uptake by potatoes could be minimised by changes in either phosphorus (P), potassium (K) or zinc (Zn) fertilizer management. Changing the chemical form in which either P fertilizer (monoammonium phosphate, diammonium phosphate, single superphosphate and reactive rock phosphate) or K fertilizer (potassium chloride and potassium sulfate) were added to crops had little influence on tuber Cd concentrations. Fertilizer Cd concentrations also had little influence on tuber Cd concentrations, suggesting that residual Cd in the soil was a major contributor to Cd uptake by the crops on these soils. Addition of Zn at planting (up to 100 kg Zn ha−1) significantly reduced tuber Cd concentrations at four of the five sites studied. However, the largest variation was between sites rather than between treatments, with site mean tuber Cd concentrations varying tenfold (from 0.018 to 0.177 mg Cd kg−1 fresh weight). Factors associated with irrigation water quality at the sites, in particular the chloride concentration, appeared to dominate any effects of changing fertilizer type or Cd concentration.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-0867
    Keywords: cadmium ; chloride ; lime ; potato ; soil acidity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Cadmium (Cd) has accumulated in many agricultural soils in Australia due to fertilization with phosphatic fertilizers that contained Cd as an impurity. Nine field and seven glasshouse experiments using light-textured soils were conducted to investigate the effect of current-season applications of calcitic lime on i) soil pHw, ii) tuber yield, and iii) Cd accumulation in tubers of a range of processing (Russet Burbank, Atlantic, Shepody and Kennebec) and fresh market (Crystal, Pontiac and Desiree) potato cultivars. Liming increased soil pH values by up to 2 units. Yields of potato tubers were generally unaffected by liming. Under glasshouse conditions, significant reductions in tuber Cd concentrations were found after liming of soils. In contrast, in the field, application of calcitic lime at rates up to 20 t ha−1 had either no effect or significantly (p〈0.05) increased tuber Cd concentrations. Concentrations of Cd in tubers were closely correlated (R2=0.74,p〈0.001) with concentrations of chloride (Cl). The lack of any beneficial effect of lime application in reducing tuber Cd concentrations under field conditions is attributed to a combination of ineffective mixing of lime throughout the whole root zone, inadequate time of reaction of lime with soil, competitive desorption of Cd2+ by Ca2+ and low soil moisture inhibiting lime dissolution under field conditions. Further work is required to resolve which mechanisms are most important.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 179 (1996), S. 57-64 
    ISSN: 1573-5036
    Keywords: Cd2+ activity ; Cd-Cl interaction ; chelator-buffered nutrient solution ; salinity ; speciation ; Swiss chard
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Swiss chard (Beta vulgaris L., cv. Fordhook Giant) was grown in nutrient solution with Cl concentrations varying between 0.01 mM and 120 mM. Solution Na concentration and ionic strength were maintained in all treatments by compensating with NaNO3. All solutions contained Cd (50 nM, spiked with 109Cd). Three different Cd2+ buffering systems were used. In one experiment, Cd2+ activity was unbuffered; its activity decreased with increased Cl concentration as a result of the formation of CdCln 2−n species. In the other experiments, Cd2+ activity was buffered by the chelator nitrilotriacetate (NTA, 50 μM) and ethylene-bis-(oxyethylenenitrilo)-tetraacetate (EGTA, 50 μM) at about 10−9 M and 10−11 M, respectively. Plant growth was generally unaffected by increasing Cl concentrations in the three experiments. In unbuffered solutions, Cd concentrations in plant tissue decreased significantly (p〈0.01) (approximately 2.4-fold) as solution Cl concentration increased from 0.01 mM to 120 mM. However, this decrease was smaller in magnitude than the 4.7-fold decrease in Cd2+ activity as calculated by the GEOCHEM-PC program for the same range of Cl concentrations. In solutions where Cd2+ activity was buffered by NTA, Cd concentrations in plant tissue increased approximately 1.4-fold with increasing Cl concentration in solution, while the Cd2+ activity was calculated to decrease 1.3-fold. In solutions where Cd2+ activity was buffered by EGTA, Cd concentrations in the roots increased 1.3-fold with increasing Cl concentration in solution but there was no effect of Cl on shoot Cd concentrations. The data suggest that either CdCln 2−nspecies can be taken up by plant roots or that Cl enhances uptake of Cd2+ through enhanced diffusion of the uncomplexed metal to uptake sites.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 97 (1987), S. 391-399 
    ISSN: 1573-5036
    Keywords: Microbial biomass ; 32P ; 33P ; P flux ; P transformation ; Rhizosphere ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Wheat plants labelled with33P were grown in thin layers of soil amended with32P-labelled fertiliser. Roots were separated from the soil during plant growth by a porous membrane to overcome difficulties in measuring microbial P in rhizosphere soil. Over the 22 day growth period, net movement of33P out of healthy growing roots varied from 0.9–4.9% of the total33P translocated to the root. Over the same period the plants took up 12.0% and the microbial biomass 14.1% of the fertiliser32P. On drying and rewetting of the soil after the plants were harvested, a large proportion of root P moved into soil fractions while32P appeared to accumulate in the biomass and stable P forms.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-5036
    Keywords: aluminium tolerance ; cation-anion balance ; phosphate translocation ; split-root ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Seedlings of two cultivars of wheat (Triticum aestivum L.) differing in tolerance to aluminium (Al) were grown using a split-root sand/soil culture technique. Each culture tube was divided horizontally into a surface (0–150 mm) compartment and a subsurface (150–250 mm) compartment separated by a root-permeable paraffin wax barrier. Thus phosphorus (P) supplied to surface roots could not percolate or diffuse into the soil in the subsurface compartment. The soil in the subsurface compartment was divided into ‘rhizosphere’ and ‘non-rhizosphere’ zones using a porous (5 μm) membrane. Root growth of both cultivars into the subsurface zone was enhanced by increased P supply to surface roots, but did not conform to known relationships between root growth and soil pH, extractable-Al, or pH, Al or P concentrations in soil solution. Concentrations of Al in soil solution in the rhizosphere were greater than those in solution in the bulk soil. Concentrations of Al reactive with pyrocatechol violet (30s-RRAI) in the rhizosphere soil solution were generally greater than those in non-rhizosphere soil. With the Al-sensitive cultivar, root dry weight and length increased as concentrations of RRAl in the rhizosphere soil solution increased. Increased concentrations of Al in rhizosphere soil solutions were not related to the presence of organic ligands in solution. The effect of P in promoting root penetration into the acidic subsurface stratum was not related to differential attainment of maturity by the plant shoots, but appeared to be related to the effect of P in enhancing the rate of root growth. Thus, suboptimal supply of P to the surface roots of a plant, even at levels sufficient to preclude development of nutritional (P) stress symptoms, may seriously reduce tolerance to Al, and hence diminish the ability of roots to penetrate into acidic subsoils.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-5036
    Keywords: Cd2+ activity ; Cd–SO4 interaction ; nutrient solution ; salinity ; speciation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The impacts of both sulfate (SO4) and calcium (Ca) concentrations in solution on plant uptake of cadmium (Cd) vary according to effects on both sorption of Cd by soil and on uptake by the plant root. This study investigated how complexation of Cd by SO4 affected plant Cd uptake in nutrient solution. Swiss chard (Beta vulgaris L. cv. Fordhook Giant) was grown in nutrient solution with SO4 concentrations varying between 8 mM and 58 m M, with ionic strength maintained constant across treatments using nitrate (NO3). In a separate experiment, solution Ca concentrations was also varied to compensate for SO4 complexation by Ca. Plant growth was unaffected by increasing SO4 concentrations in solution. Despite considerable reductions in free Cd2+ ion activities in solution by increasing SO4 concentrations, plant Cd concentrations were unaffected. Similarly, plant Cd concentrations were unaffected by increasing Ca concentrations in solution to compensate for SO4 complexation of Ca. These data suggest that the CdSO40 complex is taken up by plants with equal efficiency to the free Cd2+ ion.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1573-5036
    Keywords: fluoride ; plant uptake ; pasture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Recent findings have highlighted the possibility of increased fluoride (F) concentrations in herbage through F taken up from soil via the plant root. This paper aimed to assess the risk of F concentrations reaching phytotoxic or zootoxic concentrations in pasture plants. Five plant species commonly found in improved pastures in Australia, the sown species subterranean clover (Trifolium subterranean) and cocksfoot (Dactylis glomerata), and weeds barley grass (Hordeum leporinum), scotch thistle (Onopordum acanthium) and sorrel (Rumex acetosella) were grown in complete nutrient solutions with graded levels of added F to determine the effects of F− activity in solution on phytotoxicity and uptake of F by their roots. A model was developed using data from these solution culture experiments and data from the literature. The model assessed uptake of F by plants grown over a range of soil pH values and determined the risk of F taken up through the plant roots reaching phytotoxic concentrations, or concentrations potentially injurious to grazing animals, in the plant shoots. Modelling data suggested that the plants studied would not accumulate phytotoxic concentrations of F in shoots or concentrations of F deleterious to grazing animals through root uptake in neutral pH agricultural soils. The risks from F addition to soils in phosphatic fertilisers leading to reduction in pasture growth or animal health are therefore low. However, in highly F-polluted soil, as the soil becomes more acidic or alkaline, the risk of zootoxic concentrations of F in shoots of plants would increase.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1573-5036
    Keywords: acidic soils ; exchange resins ; soil extractants ; soil testing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract We have developed a technique using cation/anion exchange resins which allows the simultaneous extraction from soil of Ca, Mg, K, Mn, Al and P. Ions are extracted by shaking soil with resin in distilled water. The resin is separated from the soil and ions are desorbed from the resin using an acid/salt solution. Concentrations of ions in solution are then determined by conventional means. Concentrations of ions extracted by the resin method were compared with concentrations determined by commonly-used analytical procedures. Except for Al, concentrations of ions extracted by the resin procedures correlated well with conventional extraction and analytical procedures. The resin membrane method offers considerable speed and cost advantages over conventional methods.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...