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1.
Summary The effect of CaCO3 and iron on the availability of iron, manganese phosphorus and calcium was studied in the greenhouse on pea (Pisum sativum L.) crop on a light textured soil, which was marginal in exchangeable calcium. Addition of calcium carbonate caused significant increase in dry matter yield with no added iron at both the stages of crop growth. But yeild intended to decrease with 8% CaCO3 at 75 days of crop growth. Dry matter yield also increased with the addition of iron upto 10 ppm at 45 days and upto 5 ppm at 75 days. The iron concentration and uptake decreased with the increase in CaCO3 and increased with the application of iron at both the stages of crop growth. The application of iron and CaCO3 decreased concentration and uptake of phosphorus significantly at both the stages.Like phosphorus, concentration and uptake of manganese also decreased with the increase in added CaCO3 upto 8% and iron upto 20 ppm at 45 and 75 days. The concentration of calcium increased with the addition of CaCO3 to the extent of 50 and 40% with 8% CaCO3 at 45 and 75 days, while the uptake of calcium increased more than 3 folds at 45 days and more than 2 folds at 75 days. The concentration of calcium decreased with the application of iron upto 20 ppm but the uptake at 45 days increased upto 10 ppm and at 75 days upto 5 ppm and then decreased.The concentration of Fe, P and Ca decreased at 75 days and that of Mn increased while the uptake of all these nutrients increased at 2nd stage due to higher dry matter.  相似文献   

2.
The effect of added CaCO3 and iron as ferrous sulphate on the availability of various forms of manganese in light-textured soil was studied in laboratory at room temperature. All forms of manganese decrease with increase in added CaCO3 upto 16%. Application of iron as ferrous sulphate also decreased all forms of manganese. The addition of iron and CaCO3 together showed additive negative effect on the forms of manganese through various reactions. The increase in the time of incubation decreases manganese extracted with all forms of extractants due to oxidation and hydration of manganese to higher insoluble oxides and hydroxides. Ammoni um acetate (pH 7.0) + 0.1 % hydroquinone extracted highest amount of manganese by reducing some of the higher oxides along with lower oxides.  相似文献   

3.
A soil incubation and short-term root growth experiment was conducted to investigate the effects of organic matter application on Al toxicity alleviation in a highly weathered acid soil. Ground leaves of a tree legume (Calliandra calothyrsus Meissn.), ground barley (Hordeum vulgare L.) straw, or CaCO3 were mixed at various rates with A-horizon soil of a red podzolic soil (Epiaquic Haplustult) and incubated at 90% of field capacity for 4 or 10 weeks. After the incubation, a short term (48 h) root growth test was conducted using mung bean (Vigna radiata (L.) Wilczek), followed by the analysis of the solution and solid phases of the post-harvest soil. Adding either CaCO3 or organic matter increased root length in mung bean largely by decreasing the activity of monomeric Al in the soil solution. With organic matter, the major mechanisms of this decrease were presumed to be precipitation of soluble Al and the formation of Al-organic matter complexes. The former effect was predicted from the pH increase accompanying the organic matter addition, the increase being larger with legume leaves which had the higher exchangeable and soluble Ca and Mg contents. The concentration of Al complexed with soluble organic matter also was shown to increase with increasing rate of organic matter addition, the effect again being larger with legume leaves. The sum of monomeric Al species activity and Al3+ activity was negatively correlated with relative root length for the organic matter and CaCO3 treatments. However, indices which took into account the possible alleviation effects of basic cations in soil solution on Al toxicity provided an improvement in correlation with relative root length. The efficiency of the two organic amendments relative to CaCO3 in decreasing Al toxicity was assessed by comparing the rates required to reduce Al3+ activity below 10 μ M, the value found to be associated with 90% relative root length for mung bean. The rates of CaCO3, legume leaf and barley straw required to reach this critical value were 0.75, 14, and 42 t ha−1 respectively.  相似文献   

4.
Summary Organic matter has been found to be closely associated with the retention of manganese in an exchangeable form. The destruction of organic matter or its addition decrease or increase the exchangeable form of manganese respectively.The removal of iron and Fe2O3 addition greatly affect the retention of manganese. An increase in Fe2O3 addition increases the retained, reducible and fixed forms (R, r and F values) of manganese in soils.  相似文献   

5.
A pot culture experiment was conducted in loamy sand soil to study the effect of different levels of FYM and CaCO3 on the dry matter yield and nutrients uptake by oats. Application of different levels of CaCO3 (0, 2, 4 and 8%) and FYM (0, 0.5, 1,2%) resulted in significant increase in dry matter yield of oats. But, a little decrease in dry matter yield was obtained at 4% FYM. The interaction of FYM×CaCO3 was also significant on dry matter yield of oats. There was a significant decrease in the concentration and uptake of P with increased levels of applied CaCO3. But, application of FYM resulted in a significant increase in concentration and uptake of P. A significant increase in concentration and uptake of Ca was observed with the increasing levels of CaCO3. The concentration of Ca decreased with the increased application of FYM in the presence as well as in the absence of added CaCO3. However, at 0.5 and 1.0 percent FYM with 4 per cent CaCO3 a little increase in Ca concentration was recorded. The Mg concentration in oat decreased significantly with the increasing levels of CaCO3 and FYM. The effect of CaCO3 levels was more pronounced in the absence as well as in the presence of FYM. The Mg uptake followed a different pattern. At 0 and 2% CaCO3 and application of FYM @ 1 per cent the Mg uptake increased but then it decreased with increasing levels of FYM and CaCO3 both alone as well as in the presence of each other. The concentration and uptake of Mn decreased with increasing levels of applied CaCO3. However, in the absence of CaCO3, the application of FYM increased the concentration and uptake of Mn in oats. In the presence of CaCO3, Mn concentration decreased at all levels of FYM application but at 8 per cent CaCO3 there was a slight increase in Mn concentration with 0.5, 2 and 4 percent FYM. Iron concentration and uptake was also affected adversely by increasing levels of CaCO3 but FYM application removed the harmful effect of CaCO3 to some extent.  相似文献   

6.
Summary Transformation of iron and manganese under three different moisture regimes,viz continuous waterlogged (W1), continuous saturated (W2) and alternate waterlogged and saturated (W3) and three levels of organic matterviz 0, 0.5 and 1.0% in all possible combinations was studied in four soils. The results showed that under waterlogged moisture regime there was a sharp increase in the content of water soluble plus exchangeable manganese accompanied by significant decrease in the content of reducible manganese in all the soils excepting the acidic soil which was very poor in active manganese content. The increase in respect of iron in similar form was, however, very small. The increase in the content of water soluble plus exchangeable manganese as well as iron under the continuous saturated and alternate waterlogged and saturated moisture regimes was always much lower as compared to that under the continuous waterlogged condition. Application of organic matter brought about an increase in the content of water soluble plus exchangeable manganese in all the soils excepting the lateritic one irrespective of moisture regimes but did not cause any change in the content of iron and manganese in insoluble complex. The content of water soluble plus exchangeable iron and of insoluble ferrous iron although recorded some increase due to organic matter application, the increase was not so marked in any of the soils.  相似文献   

7.
Summary Addition of CaCO3 to the soils has been found to increase the retention of manganese applied to soils. As the black soil contained enough of CaCO3 initially the addition of CaCO3 even upto 16% is not effective. But in red soil the effect in marked.It has also been observed that addition of CaCO3, at the rate of 1 to 8 per cent to H-soils, resulted in an increased retention of manganese.The E and r forms decrease and increase respectively with an increase in the addition of CaCO3 addition to both original and H-soils.Addition of soluble carbonates has also been found to effect the retention of manganese.The availability of manganese added to soils in the soluble form has been found to be adversely affected by the addition of both soluble and in soluble carbonates to black, red, and alkali soils.  相似文献   

8.
The effects of CaCO3, Zn sources and levels on the yield of submerged paddy and uptake of Zn, P and N to paddy were studied in green-house at Haryana Agricultural University, Hissar. Powdered CaCO3 was mixed at 0,4 and 8 per cent and Zn was added at 0,5 and 10 ppm through ZnSO4.7H2O, ZnO and Zn EDTA separately. Dry weight at tillering and heading and grain and straw at maturity decreased significantly with 4 and 8 per cent CaCO3 in comparison to the control. Increasing Zn application increased the dry weight and grain yield. Zn EDTA gave highest yield of paddy followed by ZnSO4.7H2O and ZnO.Increasing the application of CaCO3 from 0–8 per cent decreased the concentration and uptake of Zn and increasing Zn application from 0–10 ppm increased concentration and uptake of Zn in paddy at tillering, heading and maturity. Zn EDTA gave the highest concentration and uptake of Zn followed by ZnSO4.7H2O and ZnO. There was interaction between Zn sources and CaCO3.The concentration and uptake of N and P in paddy dry matter at tillering and heading and straw and grain at maturity decreased as compared to control with increasing CaCO3 addition. The concentration and uptake of N increased and that of P decreased in paddy dry matter straw and grain with increasing Zn application. The highest concentration of N was observed with ZnO, followed by ZnSO4.7H2O and Zn EDTA. But highest uptake of N was observed with Zn EDTA followed by ZnSO4.7H2O and ZnO. As regards concentration and uptake of P, it was highest with ZnO followed by ZnSO4.7H2O and Zn EDTA.  相似文献   

9.
Addition of five types of organic matter to Lake Washington sediments resulted in release of high concentrations of iron, organic carbon, and manganese into the interstitial water, and caused an increase in observed sediment oxygen consumption rates. The depressed electrode potentials (Eh < —150 mV) that should accompany such reduction processes did not occur, indicating that Eh was being poised by redox systems present in the sediment. Iron redox systems [Fe(OH)3‐Fe2+, Fe3(OH)8‐Fe2+, and Fe(OH)3‐Fe3(OH)8] were shown to be poising the Eh of control sediments throughout 13 weeks of incubation and dominating the potential of several of the organically amended sediments following the first three weeks of incubation. Depression of calculated iron system Eo values relative to that of the control sediment early in the incubation appeared to be due to the decreased pH and non‐equilibrium conditions in the organic matter‐amended sediment during the first weeks of incubation. Manganese redox systems exerted no discernable impact on the Eh of the sediment.  相似文献   

10.
In tropical Australian freshwaters, uranium (U) is of potential ecotoxicological concern, largely as a consequence of mining activities. Although the toxicity of uranium to Australian freshwater biota is comprehensive, by world standards, few data are available on the effects of physicochemical variables, such as hardness, alkalinity, pH and organic matter, on uranium speciation and bioavailability. This study determined the individual effects of water hardness (6.6, 165 and 330 mg l-1 as CaCO3) and alkalinity (4.0 and 102 mg l-1 as CaCO3), at a constant pH (6.0), on the toxicity (96 h population growth) of uranium to Hydra viridissima (green hydra). A 50-fold increase in hardness (Ca and Mg concentration) resulted in a 92% (two-fold) decrease in the toxicity of uranium to H. viridissima [i.e. an increase in the EC50 value and 95% confidence interval from 114 (107-121) to 219 (192-246) µg l-1]. Conversely, at a constant hardness (165 mg l-1 as CaCO3), the toxicity of uranium to H. viridissima was not significantly (P &gt; 0.05) affected by a 25-fold increase in alkalinity (carbonate concentration) [i.e. EC50 values of 177 (166-188) and 171 (150-192) µg l-1 at 4.0 and 102 mg l-1 as CaCO3, respectively]. A knowledge of the relationship between water chemistry variables, including hardness and alkalinity, and uranium toxicity is useful for predicting the potential ecological detriment in aquatic systems, and can be used to relax national water quality guidelines on a site-specific basis.  相似文献   

11.
Summary The effect of the salinity, alkalinity and Fe application on the dry matter yield and availability of Fe, Mn, P and Na were studied in the greenhouse on pea (Pisum sativum L.) crop. The highest dry matter yield was recorded in normal soil which decreased with the increase in the salinity and alkalinity, minimum being at 40 ESP. Alkalinity was more harmful to pea crop than salinity.Fe at 10 ppm increased the dry matter yield significantly. Highest Fe concentration (408.12 ppm) was recorded in 40 ESP soil followed by 20 ESP (395.2 ppm). Salinity alongwith marginal or higher alkalinity reduced harmful effect of alkalinity. The uptake of Fe was the highest in normal soil due to the high dry matter yield. All the three sources increased the concentration of Fe and its uptake than the control in all the soils but did not show much distinction among themselves.The concentration of Mn decreased more with the increase in alkalinity than salinity but salinity with alkalinity improved Mn concentration. Similarly uptake of Mn also decreased sharply with the increase in salinity and alkalinity. The application of Fe sources decreased Mn concentration but increased the uptake. The highest decrease was caused with FeSO4 and lowest with Fe rayplex.Like Mn the concentration and uptake of P decreased with the increased levels of salinity and alkalinity. The addition of Fe decreased the concentration of P, highest depression being with Fe KE-MIN.Increase in ESP increased the concentration and the uptake of Na greatly. Addition of Fe through all the sources increased Na concentration and uptake significantly but sources did not differ much in their effect on Na.  相似文献   

12.
Our study investigates the effect of iron deficiency on morpho-physiological and biochemical parameters of two Medicago ciliaris ecotypes (Mateur TN11.11 and Soliman TN8.7). Iron deficiency was imposed by making plants grow, either in an iron free or by the addition of CaCO3/NaHCO3 to the Hoagland nutrient solution. Our results showed that both true and bicarbonate Fe-deficiency induced the characteristic iron-chlorosis symptoms, although the intensity of the symptoms was ecotype-dependent. This variability in tolerance to iron deficiency was also displayed by other morphological parameters such as root biomass and chlorophyll concentration. Besides, iron chlorosis induced an increase in biochemical parameters: the iron reducing capacity (measured in vivo on root segments and in vitro on plasma membrane enriched vesicles) and rhizosphere acidification by enhancement of H+-ATPase activity were more pronounced in Mateur ecotype. These findings suggest that Soliman ecotype was more sensitive than Mateur one to iron chlorosis.  相似文献   

13.
Summary The sulphide-ion electrode was used to study the kinetics and reactions of free hydrogen sulphide in solution of flooded rice soils. The observed sulphide potential obeyed the Nernst equation over a range of sulphide-ion concentration from 10-1 to 10-19 M. Peak H2S concentrations were lowest in neutral soils high in iron and manganese; moderately high in soils low in iron or high in organic matter; and highest in acid sulphate soil low in iron. Harmful concentrations of H2S may be present in acid sulphate and acid soils low in iron during the first few weeks after flooding. The concentrations in acid sulphate soils can be drastically lowered by liming. There was thermodynamic evidence for the presence of FeS and ZnS in the solutions of most soils.  相似文献   

14.
Batch fermentation of 60g/l glucose/xylose mixture by Clostridium acetobutylicum ATCC 824 was investigated on complex culture medium. Different proportions of mixtures, ranged between 10 and 50g of each sugar/l, were fermented during pH control at 4.8 (optimum pH for solventogenesis) or during CaCO3 addition. Using xylose-pregrown cells and pH control, an important amount of xylose was left over at the end of the fermentation when the glucose concentration was higher than that of xylose. The addition of 10g of CaCO3/l (to prevent the pH dropping below 4.8) increased xylose uptake: a substantial decrease of residual xylose was observed when xylose-pregrown cells as well as glucose-pregrown cells were used as inoculum for all the mixture proportions studied. MgCO3 (Mg2+-containing compound) and CaCl2 (Ca2+-containing compound) reduced residual xylose only during pH control at 4.8 by NaOH addition. As butanol is the major limiting factor of xylose uptake in C. acetobutylicum, fermentations were carried out with or without CaCO3 in butanol-containing media or in iron deficient media (under iron limitation, butanol synthesis occurred early and could inhibit xylose uptake). Results showed that an excess of CaCOCaCO3 could increase butanol tolerance which resulted in an increase in xylose utilization. This positive effect seem to be specific to Ca2+- or Mg2+-containing compounds, going beyond the buffering effect of carbonate.  相似文献   

15.
Temporal and longitudinal variations in the chemistry of two tributary streams of Woods Lake in the Adirondack Mountains of New York were monitored before and after a watershed CaCO3 application. One subcatchment of the lake had a large beaver pond and wetland at its headwaters, while the second was free-flowing. Treatment of both subcatchments with CaCO3 resulted in an immediate increase in acid neutralizing capacity (ANC) associated with Ca2+ release. The extent and duration of the response to the treatment were greater in the wetland-impacted stream. Aluminum was retained and complexed with organic solutes generated within the beaver-pond. In the free-flowing stream, NO 3 concentration increased significantly after the manipulation; this pattern was not evident in the wetland-impacted stream. Net retention of SOkinf4/sup2– was evident in the beaver pond prior to and following treatment, and this response was enhanced after the watershed liming. Comparisons of beaver pond inlet/outlet concentrations, mass balance calculations, and in-pond profiles of chemical parameters revealed patterns of retention of SO 4 2– , NO 3 and Al, and release of Fe2+, dissolved organic carbon (DOC) and NH 4 + in the wetland during the summer before CaCO3 treatment. Post-treatment releases of Ca2+ from the near-sediment zone in the beaver pond corresponded to anoxic periods in mid- to late-summer and under ice in winter. These findings demonstrate the importance of increased microbial processing of organic matter, along with high partial pressure Of CO2 (Pco2) in facilitating the dissolution of the applied CaCO3. Dissolved silica (H4SiO4) was retained in the wetland during the summer prior to treatment but was released after the manipulation. This phenomenon may reflect the dissolution of diatom frustules or silicate minerals in the wetland at higher pH and DOC concentrations. Within two years of the CaCO3 treatment 60% of the CaCO3 applied to the beaver pond and surrounding wetland was dissolved and transported from the pond, in contrast to only 2.2% of the CaCO3 applied to the upland subcatchment draining into the wetland. These results, coupled with high quantities of exchangeable Ca2+ found in sediments and onSphagnums mosses in the pond, demonstrate the importance of hydrologic source areas and wetlands in facilitating the dissolution of added CaCO3 and in regulating the production of chemical species important in ANC generation.  相似文献   

16.
Summary The effect of carbonic anhydrase (CA), urea and urease on the CaCO3 deposition in the shell-repair membrane of the snail, Helix pomatia, was studied by injection of CA separately or in combination with urease. This treatment resulted in increased deposits of CaCO3 and apparent crystal formation within the shell-repair membranes compared with those of the controls. The reactions to CA combined with urea were not uniform. Formation of organic crystalline structures and dendritic spherulites was observed in some of these membranes, whereas the deposition of CaCO3 crystals was suppressed. Administration of urea alone inhibited the formation of large CaCO3 crystals, whereas urease stimulated this process. The reaction of young snails was greater compared to adults. The membranes of young snails contained tighly packed, small CaCO3 crystals and organic crystalline structures, which indicated increase of the calcifying centra and their successive mineralization. The results support the assumption that carbonic anhydrase and urease enhance the rate of calcium carbonate deposition and crystal formation in Helix pomatia.  相似文献   

17.
Summary Laboratory experiments were conducted to study the effect of algal growth on the change of (I) pH, (II) available phosphorus and (III) solubility of iron and manganese content in five waterlogged alluvial rice soils of West Bengal, India. The results showed that the algal growth initially caused an increase in the soil pH, which later declined to the original value in some of the soils. The available phosphorus content decreased upto 90 days of their growth and began to increase towards the later period of incubation. The drastic fall of water soluble plus exchaneable manganese content of the soils due to algal growth was accompanied by similar increase in reducible manganese content. No appreciable change in water soluble plus exchangeable ferrous iron content was encountered but theN-NH4OAC(pH 3) extractable iron due to algal growth progressively decreased with the progress of the incubation period.  相似文献   

18.
H. Ssali 《Plant and Soil》1981,62(1):53-63
Summary The effect of level of CaCO3, inoculation and lime pelleting on the nodulation, dry matter yield and % N content of common bean plants (Phaseolus vulgaris) grown in five acid soils was investigated in a greenhouse study. The soils represented a range in pH from 3.9 to 5.1, in exchangeable Al from 0.0 to 4 meq/100 gm, in exchangeable Mn from 0.35 to 2.32 me/100 gm, and in %C from 0.69 to 5.60.Nodule weight decreased with increasing %C and for the soil with highest %C (5.60) no nodules were observed. In soils with low organic matter and low exchangeable Al and Mn, inoculation increased nodule weight, dry matter yield and %N especially at the lowest pH level. Where the seeds were not inoculated, nodule weight and dry matter yield increased with soil pH. No such increases were observed where the seeds were inoculated. There was no apparent advantage in lime pelleting in such soils.In soils with low organic matter content and with substantial amounts of Al and/or Mn, liming increased nodule weight and dry matter yield, and decreased exchangeable Al and/or Mn. Lime pelleting was superior to mere inoculation in increasing nodule weight particularly at low lime rates.In soils with relatively high organic matter content, nodulation was very low or none at all. Low lime rates had little effect on exchangeable Al and Ca and dry matter yield. Higher lime rates, however, decreased exchangeable Al and dry matter yield but increased exchangeable Ca.  相似文献   

19.
Abstract

Calcium carbonate (CaCO3) is found in different polymorph structures such as aragonite, vaterite, and calcite. The most common and stable form of CaCO3, calcite, which is abundant in sedimentary rocks as magnesite ore. Magnesite has application areas in many industrial fields including paper, pharmaceutical and refractory materials. Magnesite is theoretically formulated MgCO3, but contains many impurities (silicium, iron, and also calcite), that limits its usability and applicability. In this research, we aimed to investigate the decalcification possibility of the raw magnesite material through application of Enterococcus feacelis (EF) with CaCO3 dissolution ability. The exact mechanism of CaCO3 dissolution was investigated by carbonic anhydrase enzyme assay and HPLC analysis of organic acids produced by EF. Consequently, EF reduced the amount of CaCO3 from 2.94% to 0.49% which means a reduction (≈83.33%) in the rate of CaCO3 percentage. As a result of the experiments, it was observed that different organic acids produced by bacteria reacted with CaCO3 and removed the lime of magnesite ore. The bacteria used in the study did not show any pathogenic properties in rats, thus, it can be used safely for the industrial applications.  相似文献   

20.
The accumulation of carbonate and carbonaceous matter increased during the glacial age due to intensified sink water formation in the northernmost Atlantic Ocean and the intensified upwellings in the Indo-Pacific Oceans. As a consequence of that there was a decrease of the ΣCO2 concentration in the ocean as well as of the CO2 content in the atmosphere.As a whole the accumulation area of calcareous matter was enlarged by ca. 20% during glacial times. The decreased accumulation area in the North Atlantic was well compensated by a large increase in the Indo-Pacific oceans.The northernmost part of the Atlantic Ocean was quasi-stagnant during the most intense deglacial times, thus causing a reduced exchange between surface water and deep water which, in its turn, led to a decrease of the accumulation of carbon (as CaCO3 and organic matter). The concentration of ΣCO2 rose in the seawater and the pCO2 increased as well.  相似文献   

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