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1.
Revegetation of copper mine tailings with ryegrass and willow   总被引：12，自引：0，他引：12  
To restore vegetation on metal mine tailings is very difficult because they often contain high concentrations of heavy metals, low nutrient content and low water retention capacity. This study involved 3 experiments that evaluated the effects of 4 treatment amendments: montmorillonite, rice straw, organic manure and chemical fertilizer on the growth of ryegrass (Loliurn perenne L.) and willow (Salix virninalis L.) with Cu and Zn mine tailings from two mining areas. The results showed that ryegrass was the most tolerant of 4 crops to Cu toxicity. Also when organic manure, which contained high concentrations of inorganic salts, was added to the mine tailings, it significantly hindered ryegrass growth (P=0.05).Meanwhile, with ryegrass organic manure significantly increased (P=0.05) the extractable Cu concentration in both mine tallings. When montmorillonite was used as a mine tailings amendment with willow, the height and tress number at the 1st cut were significantly greater (P = 0.05) than a control without montmorillonite. However there was no significant difference for height, tress number, dry weight or root dry weight at the 2nd cut. So, amendment applications to reduce metal toxicity and increase nutrients retention in mine tailings were essential during revegetation of mine tailings.  相似文献   

2.
Crop and native plants can be characterized as high and low nutrient‐adapted based on their expected response to native and applied nutrients. Our objective was to compare the plasticity of biomass allocation and tissue nutrient concentrations to added sulfur (S) and nitrogen (N) across a continuum of high and low nutrient‐adapted grasses, represented by barley (Hordeum vulgare), smooth brome (Bromus inermis), bluebunch wheatgrass (Pseudoroegneria spicata), and Idaho fescue (Festuca idahoensis). In our greenhouse study, treatments included two S sources (pyrite and gypsum), at 150 and 300 kg S ha‐1, N at 50 kg ha‐1, and a check. Shoot biomass of barley, smooth brome, and bluebunch wheatgrass was enhanced by S plus N. Shoot biomass of barley and smooth brome was greater with pyrite than with gypsum. Root biomass of smooth brome and bluebunch wheatgrass was greater with pyrite than with gypsum. Plant S concentrations of barley and Idaho fescue were enhanced by added S. Plant S concentrations in barley and smooth brome were greater with gypsum than with pyrite. Except for barley, plant S pools (shoot biomass x shoot S concentration) were enhanced with S plus N compared with no added nutrients. Nitrogen pools of barley, smooth brome, and bluebunch wheatgrass were higher with pyrite than with gypsum. Soil sulfate (SO4) was greater when S or S plus N was added than without any added nutrients. For barley and smooth brome, soil sulfate tended to be lower with pyrite than with gypsum. For all soils, pH was lower with added S or added S plus N compared with unamended soils. While pyrite lowered soil pH, gypsum tended to increase soil pH. Overall, barley and smooth brome were highly plastic in responding to enhanced nutrient levels, bluebunch wheatgrass was relatively responsive, and Idaho fescue was least responsive.  相似文献   

3.
A 40-day gnotobiotic microcosm experiment was carried out to quantify the effect of bacterial-feeding nematode on plat growth and nutrient absorption.The results showed that inoculation of bacterial-feeding nematode Protorhabditis sp.stimulated the growth of wheat (Triticum aestivum) and the uptake of N.By the end of the 40-day incubation wheat biomass and N uptake in the treatment with nematode and bacteria (Pseudomonas sp.)increased by 6.5% and 5.9%,respectively,compared with bacteria alone treatment.The presence of nematode mainly accelerated the growth of aboveground of wheat,while it slightly inhibited the root development.There was little difference in plant tissue N concentration between treatments.P concentration and uptake of wheat,however,were generally reduced by nematode, It appears that the enhancement of plant growth and nitrogen uptake is attributed to the enhancement of nitrogen mineraliztion induced by nematode feeding on bacteria,and the reduction of phosphorous uptake is the result of ewak root status and comptetition by bacteria immobilzation.  相似文献   

4.
An experiment was conducted with Phalaris aquatica L. cv. Sirolan under hydroponic conditions in the glasshouse at constant temperature of 25°C and natural sunlight. Plants were grown in double pot system with four sulfur and three molybdenum levels along with all the major‐ and micro‐nutrient elements. There was increase in growth, nitrate‐reductase activity and contents of most of the nutrient elements at all levels of sulfur and 1.68 μ/L molybdenum. Molybdenum at 3.36 μg/L level inhibited growth and nitrate‐reductase activity and decreased concentration of nutrient elements in plant. The inhibitory effect of higher level of molybdenum is perhaps mediated through its role in the nitrate‐reductase.  相似文献   

5.
Background, Aim and Scope.  The compositional study of suspended matter in water from rivers of different latitudes and climates has revealed that the fine fraction reflects both substrate lithology from source areas or topsoil composition along the course. Metal distribution patterns are also strongly related to the clay mineral fate in fluvial aquatic systems. For the particular case of the coastal area of the Río de la Plata estuary in South America, previous studies have, on the one hand, focused on the analysis of distribution patterns of heavy metals in bottom river sediments and, on the other hand, on the assessment of metal contents in topsoils. The present study was conducted to evaluate the Cu, Pb and Zn distribution in soils and sediments from four drainage basins crossing two differentiated geomorphologic units composed of unconsolidated materials and to understand the metal behaviour. Methods  Data used included the existent, self-produced soil and sediment data sets (grain size, organic matter and Cu, Pb and Zn contents from 124 samples). Analyses were performed by using standardised methods: grain size analysis by sieving and settling; organic matter content based on the reduction of dichromate ion followed by titration; metal content by atomic absorption spectrophotometry following acid digestion. Results and Discussion. The average (% w/w) clay and organic matter content were 45.9 ± 17.1 and 1.5 ± 1.7 for sediments and 32.0 ± 19.8, and 7.5 ± 7.6 for soils, respectively. The raw mean metal concentrations (mg-kg-1 dry weight) for sediments and soils were: Cu: 28.02 ± 27.28, 32.08 ± 21.64; Pb: 32.08 ± 46.94, 68.44 ± 69.25 and Zn: 83.09 ± 150.33, 118.22 ± 74.20, respectively. A good correlation for each clay-normalised metal concentration was found between soil and sediments using regression analysis considering average data for each basin sampling site (r > 0.89, p < 0.05). A comparison between metal concentration levels taking into account geomorphologic units by a t independent sample test showed significant differences for the normalised soil-sediment metal data (p < 0.001), responding to differences in grain size, clay mineralogy, organic matter and neoformed Fe-Mn oxide composition. Conclusion, Recommendation and Outlook  A clear parenthood between the topsoils and the bottom sediments in the study area was found. The Argiudolls from the inner zone are frequently affected by rainwater erosion, which washes the fine materials with sorbed metals and carries them to the streams. These watercourses reach the flat coastal plain, where soil flooding and bottom sediment depositional processes predominate. Here, both soils and bottom sediments are enriched in clay, organic matter and metals. The topography and lithology, under the environmental conditions of a temperate and humid climate control the fate of metals within these small basins. The influence of the physical media on the distribution and fate of pollutants should not be minimised in the understanding of the governing processes from natural systems.  相似文献   

6.
Abstract

Two types of soils (Brown Lowland soil and Ando soil), which were artificially enriched with different amounts of Cu, were incubated with or without pulverized orchard grass for 12 weeks at 25°C. For both soils with and without orchard grass amendment, the amount of CO2 evolved over the 12-week period of incubation decreased by the enrichment with Cu at a concentration exceeding 1,000 mg kg?1 soil. The decrease of the mineralization of added orchard grass in the Cu-enriched soil was conspicuous especially during the initial period of incubation. The amount of microbial biomass C at the end of the incubation was significantly reduced by the Cu enrichment regardless of the amendment with orchard grass. The relative decrease of the soil microbial biomass was much greater than that of the soil respiration. The amount of biomass C was negatively correlated with the amount of 0.1 M CaCl2-extractable Cu as a logarithmic function. On the other hand, the β-glucosidase activity at the end of the incubation was not significantly affected by the presence of Cu in the soils without orchard grass amendment and increased with the increase in the amount of enriched Cu in the orchard grass-amended soils.  相似文献   

7.
Several interelemental relationships have been examined in field‐cultivated wheat (Triticum aestivum L. cv Vergina) growing on naturally enriched copper (Cu) soils. Mean soil Cu concentration per site ranged from 103–394 μg.g‐1 dry weight (DW). Interrelationships between Cu, iron (Fe), calcium (Ca), potassium (K), zinc (Zn), lead (Pb), and magnesium (Mg) concentrations in the soil and plant tissue (roots, stems, and leaves) were examined using Principle Components Analysis. Soil samples were clustered according to collection site and were primarily differentiated according to their Cu concentrations. Soil Cu concentrations were positively correlated with Zn, Ca, Fe, and K in the soil, with Cu, K, and Ca in the roots, and Cu and Fe in the leaves and negatively correlated with Fe in the roots. The increase in Cu in the roots and leaves was positively correlated with increases in K and Ca in the roots and Fe and Ca in the leaves, but negatively with Fe in the roots. Increases in leaf Ca concentrations were correlated with increases in Mg and decreases in Zn concentrations in the leaf. Plants growing in soil with high Cu concentration exhibited toxicity symptoms with reduced height, decreased total leaf area and lower chlorophyll concentrations. Photosynthesis expressed per unit leaf area was not affected by increasing Cu concentrations in the soil or plant tissue.  相似文献   

8.
Abstract

Extracting sludge‐amended soil with DTPA does not always give a reliable measure of plant‐available heavy metals. The major purpose of this greenhouse pot study was to help explain why. Two anaerobically digested sludges from sewages treated with either Ca(OH)2or FeCl3were applied to 3‐kg samples of a Mollic Albaqualf previously limed with Ca(OH)2rates of 0, 2.5, and 10g/pot that resulted in pHs in the check pots of 5.4, 6.2, or 7.7 after the first harvest. Sludge rates provided 0, 200, 40, 800, and 1600 mg Zn kg‐1of soil. Two consecutive crops of soybeans (Glycine MaxL.) were grown for 42 d each in the greenhouse. DTPA‐extractable, soil‐solution, and plant concentrations of Cu2+, Ni2+, and Zn2+were measured.

Dry matter yields were depressed due to salt toxicity, while DTPA‐extracted Cu2+correlated with plant uptake of Cu2+for both sludges. DTPA‐extracted Ni2+also correlated with plant Ni2+from the Ca(OH)2‐sludge‐amended soil, although DTPA‐extracted Ni2+did not correlate with plant uptake of Ni2+from the FeCl3‐sludge‐amended soil, DTPA‐extracted Zn did not correlate with plant uptake of Zn2+from any sludge‐amended soil. Soil‐solution composition correlated with plant uptake of Cu2+and Ni2+in both sludges; it also correlated with plant uptake of Zn2+from FeCl3‐sludge‐amended soil but not from Ca(OH)2‐sludge‐amended soil. DTPA extraction probably failed with Ni2+and Zn2+because of (i) its ineffectiveness at low pH, (ii) the inability of DTPA to buffer each soil extract near pH 7.3, and (iii) increased amounts of soluble chelated micronutrients at higher sludge rates and higher soil pHs. Soil‐solution composition seemed to fail only where micronutrient cations in solution probably were present largely as organic chelates  相似文献   

9.
Abstract

Chemical fractions of copper (Cu) and zinc (Zn) in the organic‐rich particles collected from filtered aqueous extracts (<20 μm) of an acid soil were determined. A sequential extraction procedure was used to partition the particulate Cu and Zn into four operationally defined chemical fractions: adsorbed (ADS), iron (Fe) and manganese (Mn) oxides bound (FeMnOX), organic matter bound (OM) and residual (RESD). Total extractable concentrations of Cu and Zn in the fine particles were higher than their total concentrations in the original bulk soil. The concentration of particulate Cu was usually much higher than that of particulate Zn. Addition of lime stabilized sewage sludge cake and/or inorganic metal salts markedly increased the concentrations of particulate Cu and Zn in aqueous extracts, especially from limed soil. The proportional distributions of particulate Cu and Zn were quite similar. The two particulate metals were present predominantly in the ADS and FeMnOX fractions, with less (about 20%) in the OM and RESD fractions. Some of the ADS metal fraction was associated with dissolved organic substances. The concentrations of particulate Cu and Zn in the various extractable fractions were significantly affected by the application of lime, lime stabilized sewage sludge cake, or inorganic metal salts.  相似文献   

10.
Abstract

Equilibrium adsorption experiments on zinc (Zn), cadmium (Cd), copper (Cu), and lead (Pb) were conducted in three horizons of two Ultisols and one Oxisol with and without liming, from Viçosa‐MG (Brazil). Equilibrium solutions were applied as a “cocktail”; containing 700 mg L‐1 of Zn, 20 mg L#lb1 of Cd, 200 mg L‐1of Cu, and 300 mg L‐1 of Pb and its dilutions of 1:5 and 1:20. After shaking, the mixture was centrifuged, the supernatant collected and the pH and the concentrations of metals in the mixture were determined. Soil order, soil horizon, and liming had significant effects on the metal adsorption. Some important changes in the adsorption characteristics of the metals, especially in Zn and Cd, were observed due to competition between the different cations present in the solution. Also, desorption of Zn and Cd was observed with an increasing concentration of the solution. The adsorption data for Zn and Cd did not fit the linear, Langmuir, Freundlich, and Temkin isotherm equations for most situations, as these equations do not consider the possibility of a decrease in the amount of metal adsorbed with increasing metal competition for the adsorption sites. Due to the competition with other metals, the equations, which offered the best fit for Zn and Cd, were quadratic polynomial models. On the other hand, for Cu and Pb, the equations, which showed the best fit were linear, Langmuir, and Temkin, for different situations. The reasons for this behavior were related to the strong competitive forces for the adsorption sites presented by these two metals.  相似文献   

11.
The effects of sulfur (S) nutrition at 0.1 or 1 mM S on cadmium (Cd) toxicity measured by photosynthesis in barley (Hordeum vulgare L. cv. UC 476) seedlings were studied. Eight‐day‐old seedlings were treated with 25 μM Cd by adding cadmium chloride (CdCl2) to the nutrient solution. Then photosynthetic carboxylation efficiency (ACi curve) and stomatal conductance of the primary and second leaves were measured at four and eight days after Cd treatment. Fluorescence parameters were measured every 24 h for eight days after two days of Cd treatment. At 20 days, plant growth parameters were measured and dry biomass determined. The results showed that ACi was significantly reduced by Cd, but more in the low (0.1 mM) S than in the high (1 mM) S‐treated plants. Stomatal conductance of plants was also decreased by Cd, but more in the low S‐treated plants. Low S‐treated plants exposed to Cd showed an increase in Fo and Fq, and a decrease in Fv/Fm and T1/2, indicating photoinhibitory damage to PSII. Analysis of the growth parameters showed that Cd decreased plant size and biomass, but the reduction was more severe in the low S‐treated plants. These results support the hypothesis that S is a critical nutritional factor in plants which is important for the reduction of Cd toxicity.  相似文献   

12.
Abstract

The environmental impact of copper sulfate (CuSO4#lb5H2O) must be evaluated before the chemical can be registered as a pesticide to control the apple snail (Pomacea canaliculata) in Hawaii's wetlands. To help achieve this goal, we investigated the sorption‐desorption reactions of CuSO4#lb5H2O with six wetland‐taro soils (Tropaquepts) of Hawaii. Our results indicated that: (i) copper (Cu) was sorbed rapidly: 98.0–99.9% of the added Cu was removed from solution within one hour when the loading rate was less than or equal to 300 mg Cu kg‐1 [initial Cu concentration = 30.0 mg Cu L‐1 or 12 kg (ha‐cm)‐1 as CuSO4#lb5H2O which is 10 times the maximum recommended rate of pesticide applications, (ii) Cu sorption increased as soil pH increased from 5.0 to 8.0, and (iii) sorption capacity varied from 210 mg Cu kg‐1 in a Tropaquept from Kauai Island to 500 mg Cu kg‐1 in another Tropaquept from Maui Island, after seven days of incubation at soil‐solution pH 6.0 and total solution Cu concentration of 0.10 mg Cu L‐1, a Cu level deemed toxic to some living organisms. It appears that more Cu was sorbed (less Cu remained in solution) if the soil contained high organic carbon (C) and low indigenous Cu. Also, there was an inverse relationship between Cu sorption and desorption by the soils tested: the more Cu a soil can sorb, the tighter it holds Cu, and the less Cu it releases. Since soil pH increases by 1 to 1.5 units upon flooding and Cu sorption increases with increasing pH, the recommended practice of flooding the soil for at least 48 hours between CuSO4#lb5H2O application and crop planting should be followed.  相似文献   

13.
Abstract

The fractionation of heavy metals in previously sludge‐amended soil is important to evaluate their behavior in the environment in terms of mobility and availability to crop plants. A surface soil that received two types of sludges at two different rates, plus fertilizer only and no treatment (control), having been fallow for nine years, was used in this study. The contents of cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) fractions in previously sludge‐amended soils were governed by the total content of these metals in the sludges applied and by the rate of sludge application. The contents of these metals were higher for soils that received the Chicago sludge as compared to that receiving the Huntsville sludge. Furthermore, soils that received 20 Mg/ha/yr of sludge for five years generally had higher levels of these metals than those receiving a single dose at the 100 Mg/ha application rate. The percentage of the total content in the water soluble and exchangeable forms was very low (≤1%) regardless of sludge application. The application of sludges tended to reduce the residual fraction and to increase the organic and carbonate fractions. Overall, the predominant forms of the metals in the sludges were as the Cd‐, Ni‐, Pb‐, and Zn‐carbonate and Cu‐organic fractions.  相似文献   

14.
Rice (Oryza sativa L.) plants were grown over a 30‐day‐period in nutrient solutions containing increasing copper (Cu) concentrations (0.002, 0.01, 0.05, 0.25, 1.25, and 6.25 mg/L). It was observed that in both root and leaf tissues the total activity of l‐aminocyclopropane‐l‐carboxylate synthase decreased at concentrations above 0.05 mg/L Cu treatment, whereas the total activity of the ethylene forming enzyme slightly increased until the 1.25 mg/L Cu treatment. In the root and leaf tissues, the 1‐aminocyclopropane‐l‐carboxylic acid concentrations decreased after the 0.05 mg/L and 0.01 mg/L Cu treatments, respectively, whereas the ethylene production decreased in both tissues after the 0.05 mg/L Cu treatment. It is proposed that excess Cu in both root and leaf tissues decrease the conversion of S‐adenosylmethionine to 1‐aminocyclopropane‐l‐carboxylic acid through the inhibition of the total l‐aminocyclopropane‐l‐carboxylate synthase activity. The concomitant effect of this inhibition on adventitious root formation and leaf senescence is evaluated.  相似文献   

15.
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16.
Abstract

In this study, a new parallel and sequential extraction procedure was proposed to investigate the solubility of metals [cadmium (Cd), zinc (Zn), copper (Cu), and nickel (Ni)] and their association with soil components in naturally metal‐rich soils of Norway. Two different soils, alum shale (clay loam) and moraine (loam), developed on alum shale minerals were used. Each soil had two pH levels. For parallel and successive extractions, H2O, 0.1M NH4OAc (soil pH), 0.3M NH4OAc (soil pH), 1M NH4OAc (soil pH), and 1M NH4OAc (pH 5.0) were used. A significant amount of Cd was extracted by NH4O Ac related to concentration of NH4OAc in the extracting solution. The amounts of Zn, Cu, and Ni extracted by these reagents were almost negligible except with 1M NH4OAc (pH 5.0). Thus these metals were strongly bound to soil components. A seven step sequential extraction procedure was applied to evaluate the association of metals with soil constituents. The extractions were performed sequentially by extracting the soil with reagents having an increasing dissolution strength: 1M NH4OAc (soil pH), 1M NH4OAc (pH 5.0), 1M NH2OH.HCl (in 25% HOAc), 1M NH2OH.HCl (in 0.1M HNO3), 30% H2O2 (in 0.1M HNO3), 30% H2O2 (1M HNO3), and aqua regia. In both soils at both pH levels investigated, appreciable percentages of total Cd (20–50%) were found associated with the NH4OAc extractable fraction (mobile fraction). For Zn, Cu, and Ni, the percentage of total metal extracted with NH4OAc was low (<4%), but it increased significantly by introducing a reducing agent (NH2OH.HCl). The NH2OH.HCl‐extractable fraction was the greatest fraction (>60%) for all four metals examined. These results suggest that among the metals studied, only Cd was easily desorbed from soil and should be considered mobile and potentially bioavailable. Other metals (Zn, Cu, and Ni) were strongly associated with the soil components and should be considered less available to plants. Using the sequential fractionation technique as a measure of availability, mobility and potential bioavailability of these four metals in the alum shale soils were: Cd>Zn>Ni>Cu.  相似文献   

17.
The distribution of the total Ni, Cu, Co, Cd, Pb, and Zn contents was studied in the soil profiles of six catenas in the zone subjected to emissions of the copper-nickel industrial complex, which is the largest source of SO2 and heavy metals in northern Europe. The results show that, at present, the concentrations of Ni and Cu in the upper organic soil horizons in the impact zone reach extreme levels of 9000 and 6000 mg/kg, respectively. Under conditions of the long-term intense multi-element industrial emissions, the modern levels of the accumulation of polluting substances in soils greatly depend on the indirect factors, such as the degree of the technogenic degradation of soils with the loss of a significant part of soil organic matter, the reaching of threshold saturation of the topsoil with polluting metals, and competitive relationships between chemical elements. The state of the ecosystems in the impact zone varied greatly and did not always agree with the contents of the main metals-pollutants in the soils. The moisture conditions determined by the landscape position affected significantly the resistance of the ecosystems to emissions.  相似文献   

18.
The diurnal pattern in concentrations of phytosiderophores (PS) and its precursor nicotianamine (NA) was studied in different root and shoot zones of iron (Fe)‐sufficient and Fe‐deficient barley (Hordeum vulgare L. cv. Europa) grown in nutrient solution. Roots were separated into apical (0–3 cm) and basal zones (>3 cm) and shoots into young (3 cm basal zones of youngest two leaves) and old (remaining zones of youngest two leaves and oldest leaf) parts. The main PS in barley was identified as epi‐hydroxymugineic acid (epi‐HMA). Regardless of the sampling zone and time of day, epi‐HMA concentrations were several times higher in Fe‐deficient than in Fe‐sufficient plants and several times higher in the roots than in the shoots. In roots and shoots, epi‐HMA concentrations were always higher in the younger compared with the older zones. In both root zones of Fe‐deficient plants, an inverse diurnal rhythm occurred in epi‐HMA concentrations and in its release by the roots. In contrast, such a rhythm was absent in roots of Fe‐sufficient plants and in the shoots regardless of the Fe nutritional status. Nicotianamine concentrations in roots were not affected by the Fe nutritional status in apical zones but slightly enhanced under Fe deficiency in basal zones. In contrast to roots, NA concentrations in both shoot parts were lower in Fe‐deficient than in Fe‐sufficient plants. Regardless of the Fe nutritional status in roots and shoots, NA concentrations were higher in young than in old parts and no consistent diurnal variations were observed. The results suggest that PS are also synthesized in the shoot, although at much lower rates than in roots. As with roots, PS synthesis in the shoot is enhanced under Fe deficiency and is mainly localized in young growing tissue. The distinct diurnal rhythm in PS release in roots is apparently not regulated by variation in the rate of PS synthesis during the day.  相似文献   

19.
Few data are available about the effects of complexation of polyphenols with polysaccharide on their bioavailability. The complex of tea polyphenols (TP) with oat β-glucan was characterized by ultraviolet-visible spectrometry, Fourier transform infrared spectrometry, differential scanning calorimetry, atomic force microscopy, and solid-state (13)C NMR spectroscopy. The results indicated that the bonds which governed the interaction between TP and oat β-glucan were strong hydrogen bonds. The in vitro antioxidant activity of TP, β-glucan, their complex, and physical mixture was assessed using four systems, namely, DPPH(?), OH(?), and O(2)(?-) scavenging activities and reducing power. The complexation and blending of TP and β-glucan exhibited different impacts on the index of in vitro and in vivo antioxidant capacities. In the concentration range of 0.5-2.5 mg mL(-1), the complex had highest O(2)(?-) scavenging activity, whereas the highest OH(?) scavenging activity was found with the physical mixture. For antioxidant testing in vivo, there was no significant difference between the complex and the physical mixture in terms of glutathione peroxidase activity and levels of malondialdehyde and total antioxidant capacity in serums. However, the complex exhibited much higher activities of superoxide dismutase and glutathione peroxidase in livers than the physical mixture. The present study provided a deeper understanding of the influence of molecular interaction between TP and oat β-glucan on their antioxidant activities.  相似文献   

20.
Abstract

Relatively high amounts of Cu are found in manure of hogs (Sus scrofa domesticus) maintained on diets containing growth‐stimulating levels of Cu. While disposal of Cu‐enriched hog manure through repeated long‐term application to agricultural land is commonly practiced, concern exists regarding Cu availability in these soils. Field studies were conducted on a Bertie fine sandy loam (Aquic Hapludults) and a Starr‐Dyke clay loam (Fluventic Dystochrepts‐Typic Rhodudults), located in the Coastal Plain and Piedmont regions of Virginia. The objective was to examine the effects of long‐term Cu application on corn (Zea mays L.) growth and to ascertain the Cu sorption capacity of these soils. Field plots were treated with Cu‐enriched hog manure or CUSO4 (on an equivalent Cu basis) annually. Manure amendments totaled about 240 t ha‐1 (dry weight) over an 11 yr period (1978 through 1989). The manure averaged 1300 mg Cu kg‐1 (dry weight) over this time period totaling 340 kg Cu ha‐1. Sorption isotherms were determined for sorption of Cu by the Bertie and Starr‐Dyke soils. In comparison with unamended control plots, studies conducted in 1989 showed an early season stunting effect for corn grown on the CUSO4 treated Bertie soil. No differences in plant heights were observed for corn grown in CuSO4 treated Starr‐Dyke soil or control plots. Plant growth rates were increased on plots amended with Cu‐enriched hog manure. Copper sorption capacity of Bertie and Starr‐Dyke soils increased following several annual applications of manure.  相似文献   

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