Excess trace metal effects on cotton: 2. Copper,zinc, cobalt and manganese in Yolo loam soil

Abstract

Two cultivars of cotton (Gossypium spp.) were grown in Yolo loam soil (soil pH about 6) in pots in a glasshouse to determine phytotoxic effects of excesses of Cu, Zn, Co, and Mn. Leaf yields of cv. Acala SJ‐2 were depressed 35% by 400 μg Cu/g soil, 54% by 400 μg Zn/g soil, 98% by 400 μg Co/g soil, and 84% by 2000 μg Mn/g soil. Leaf metal concentrations at these application levels in μg/g leaf were 12.0 Cu, 520 Zn, 243 Co, and 14780 Ma, respectively. Plants were tolerant of in / dry leaves of 10 Cu, 157 Zn and 444 Mn. The concentration for Co could not be ascertained. Leaf yields of cv. Giza 70 were depressed 53% by 400 μg Cu/g soil, 25% by 400 μg Zn/g soil, 92% by 400 μg Co/g soil and 90% by 2000 μg Mn/g soil. This cv. was more tolerant of Zn than Acala SJ‐2. Leaf metal concentrations at these application levels in μg/g leaf were 11.8 Cu, 312 Zn, 224 Co, and 18300 Mn respectively. Gradients of these four elements existed from leaves to stems. Many interactions with other elements were observed.     

Excess trace metal effects on cotton: 6. Nickel and cadmium in yolo loam soil

Abstract

Two cultivars of cotton (Gossypium spp.) were grown in Yolo loam soil in a glasshouse to determine phytotoxicity effects of excesses of Ni and Cd. A 200 μg/g level of Ni in soil reduced yield by 60% in Acala SJ‐2 and by 83% in Giza 45. The leaf Ni concentrations, respectively, were 146 and 165 μg/g‐ The 300 μg/g level of Cd decreased leaf yields by 60% and 75% for the two cultivars, respectively. Leaf concentrations of Cd, respectively, were 43 and 63 μg/g. There was a stem to leaf gradient of Cd for all cases. High Cd did not depress Mn concentrations in plants . as in other species but there were many mineral element interactions.     

Cyanide effects on transport of trace metals in plants

Abstract

Cyanide at levels of 50 to 100 μg NaCN/g soil was not only toxic to bush bean plants, but also resulted in increased uptake of Cu, Co, Ni, Al, Ti, and, to a slight extent, of Fe. Either the phytotoxicity from the cyanide or the metals resulted in increased transport of Na to leaves from roots. In studies with ¹⁴C‐cyanide the transport of some cyanide into plants and to leaves simultaneously with the metals was demonstrated. There was a root, stem, leaf gradient for ¹⁴C. From solutions, cyanide resulted in increased plant uptake somewhat of Cu, Zn, and Fe. The results have bearing on the use of cyanide as a metabolic inhibitor as well as on phytotoxicities of metals.     

Effect of concentration on uptake of some trace metals by plants

Abstract

The uptake by plants of somes trace metals at different concentrations was related closely to the decay constant, I. This means that for a 10‐fold increase in applied concentration, the increase in uptake was close to 4. 93 (10^0.693 = 4. 93). With some trace metals the value of Y (10^Y = ratio of uptake for 10‐fold increase in metal concentration was around 1. For generalized conditions the value of Y in the expression, (/ = uptake ratio, for different concentrations and varied around I. Some values of Y for whole plants were Ni, 0.699 with C.V. (coefficient of variation) 12.2%, Cu, 0.468 with C.V. 12.1%, Zn, 0.606 with C V. 31.5%, and Cd, 0.903 with C.V. 10.9%. From soil the values for shoots for Co were 0.855 (C.V. = 14.8%) without EDTA (ethylenediamine tetraacetic acid) and 0. 941 (C. V. = 20. 8%) with EDTA; for Cu with EDTA it was 0. 562 (C. V. = 25.8%). with EDTA; for Cu with EDTA it was 0.562 (C.V. =25.8%).     

Frequency distribution of several trace metals in 72 corn plants grown together in contaminated soil in a glasshouse

Abstract

A 9‐kg quantity of Yolo loam soil was contaminated in sequence with (In μg/g soil) 100 Cd, 100 Zn, 100 Co, 12.5 Li, and 100 Ni. Corn (Zea mays L. C. V. Golden Cross N. C. ) was grown together in the soil for 22 days from seed. Seventy‐two harvested plants were assayed separately. Several different trace metals were tested for normal and loge frequency distribution patterns. Some followed log_e normal distribution more closely than a normal distribution as indicated by kurtosis values. Two followed normal distribution more closely than log_e normal distribution. Some negative skewness was observed with the log_e normal distribution, but only that for Co was significant. The yields of the plants were significantly and negatively correlated with the concentrations of Ni, Co, Cu, and Cd in shoots. Stepwise regression analysis indicated that it was reasonably Possible to determine which of the trace metals of the mixture caused phytotoxicity. Some pairs of trace metals were highly and positively correlated: Zn‐Cu, Zn‐Cd, Cu‐Cd, Mn‐Li, Co‐Ni, Co‐Cd are examples. The mixed trace metals decreased shoot concentrations of P and Mo and increased Al and Ti relative to control plants not receiving added metals. The Si was also decreased by trace metals and was positively related to yields.     

Metal interactions in bush bean plants grown in a glasshouse in amended serpentine soils from California

Abstract

Bush beans (Phaseolus vulgaris L. C.V. Improved Tendergreen) were grown with amendments in a glasshouse in two different serpentine soils from California. These serpentine soils are not high in Ni and Cr as in other areas of the world and the purpose of the study was to define the reasons for low plant yields in these two soils. The two soils behaved very differently. One seemed to have simple P deficiency and a mild imbalance of Ca‐Mg. The other soil appeared to have a severe Ca deficiency, the correction of which tended to increase Mg uptake also, but with improved yields. Present also seemed to be Zn, Cu, Al, Ni toxicities even though the levels of each were not high by leaf analysis tests. Stepwise regression for plants from one of the soils indicated that Cu concentration in leaves accounted for 60% of the yield variation (negative correlation), that Ca accounted for 9% more of it, and that P accounted for 13% more for a total of 82%. In the presence of low levels of Ca, some, at least, of the trace metals were toxic and Cu was one.     

微生物活性指标: 重金属污染下的土壤质量敏感指标

Physicochemical properties, total and DTPA (diethylenetriaminepentaacetic acid)-extractable Cu, Zn, Pb and Cd contents, microbial biomass carbon (C) content and the organic C mineralization rate of the soils in a long-term trace metal-contaminated paddy region of Guangdong, China were determined to assess the sensitivity of microbial indices to moderately metal-contaminated paddy soils. The mean contents of total Cu, Zn, Pb and Cd were 251, 250, 171, and 2.4 mg kg^-1 respectively. DTPA-extractablc metals were correlated positively and significantly with total metals, CEC, and organic C (except for DTPA-extractable Cd), while they were negatively and highly significantly correlated with pH, total Fe and Mn. Metal stress resulted in relatively low ratios of microbial biomass C to organic C and in remarkable inhibition of the microbial metabolic quotient and C minera]ization rate, which eventually led to increases in soil organic C and C/N. Moreover, microbial respiratory activity showed a stronger correlation to DTPA-extractable metals than to total metal content. Likewise, in the acid paddy soils some "linked" microbial activity indices, such as metabolic quotient and ratios of basal respiration to organic C, especially during initial incubation, were found to be more sensitive indicators of soil trace metal contamination than microbial biomass C or basal respiration alone.     

Accumulation of cadmium and other metals in organs of plants growing around metal smelters in Japan

Abstract

It is well known that some plants can adapt to a high concentration of metals that would be lethal to other plant species and also accumulate toxic metals in their body up to a very high level (Peterson 1983). Athyrium yokoscense communities are often observed on highly polluted soils with heavy metals originating from mining or smelting facilities. A. yokoscense and some species of plants which can grow vigorously on highly polluted soils have attracted the attention of miners and investigators as indicator plants for mining areas (Honjo 1990; Nishizono et al. 1987).     

Tolerance of rice plants to trace metals

Abstract

The tolerance of rice (Oryza sativa L. C.V. Earlirose) to various trace metal excesses was tested to determine if high levels of the trace metals found in some field‐grown plants were at toxicity levels. In one experiment, levels of 2200 μg Zn/g dry weight, 44 μg Cu/g dry weight, 4400 μg Mn/g dry weight, and 32 μg Pb/g dry weight in shoots of young plants had no adverse effects on vegetative yields. A level of 3160μgZn/ g dry weight decreased yields about 40% (P = . 05). In another test 51 μg Cu/g dry weight or 94 μg Pb/g dry weight did not decrease vegetative yields. Boron supplied at 10^‐3 MH₃BO₃ not only caused no toxicity but resulted in only 144 μg B/g dry weight in shoots. Root levels of Zn were about equal to those in shoots; Mn levels were lower in roots than in shoots (1/4 to 1/10); B levels were generally low in both shoots and roots with roots 1/10 that of shoots; Cu levels were higher in roots than in shoots. Rice was tolerant of a high level of Cr. The tolerance of rice to high levels of some trace metals in these experiments may be related to high P levels in plants.     

Synergistic effects of heavy metal pollutants on senescence in submerged aquatic plants

The effects of many combinations of toxic concentrations of heavy metal pollutants, viz., mercuric chloride, lead acetate, cadmium chloride and cupric sulphate, on the senescence of isolated mature leaves of submerged aquatic plants, Potamogeton pectinatus L., Vallisneria spiralis L., and Hydrilla Verticillata (L.f) Royle were studied. All of the combinations of heavy metal pollutants caused senescence in all three species by decreasing chlorophyll, DNA, RNA, protein and dry wt, and increasing free amino acid, tissue permeability, the activities of protease and RNase, and the ratio of acid to alkaline pyrophosphatase activity over control values. The effects were highest in Potamogeton and lowest in Hydrilla. The degree of senescence in the three submerged plants by combinations of toxic concentrations of heavy metal pollutants is much higher due to synergism than that by individual heavy metal pollutants.     

Excess trace metal effects on cotton: 5. Nickel and cadmium in solution culture

Abstract

Two cultivars of cotton (Gossypium spp.) were grown in solution culture in a glasshouse to determine phytotoxicity effects of excesses of Ni and Cd. Leaf yield was depressed 94% by 10‐⁴ M NiSO₄(with 198μg Ni/g leaf) in Acala SJ‐2 and 93% (with 167μg Ni/g) in Plma PS‐5. The Ni gradient was roots > stems > leaves in both cultivars. At 10^‐5 M, CdSO₄ gave more phytotoxicity than NiSO₄. The 10^‐4 M CdSO₄ resulted in about the same amount of phytotoxicity as did the Ni for both cultivars. The Pima PS‐5 plant parts, however, contained less Cd than did the Acala SJ‐2 at the highest Cd concentration. At 10^‐5 M CdSO₄ the reverse held in leaves and stems. Interactions held for both metals but the inverse effect between Cd and Mn was less pronounced than for other species. Many other interactions were present.     

Specific sorption of trace amounts of cadmium by soils

Abstract

Sorption of trace quantities of Cd in four soils of different chemical and mineralogical properties, was studied. Initial Cd concentrations were between 15 to 150 μg. 1^?1. The sorption isotherms were linear and had a positive intercept in three of the soils, indicating a constant partition‐high affinity sorption isotherm (Giles et. al⁶). The data also followed the Freundlich sorption isotherm, and the Freundlich K parameter was taken as a measure of the relative affinity of the different soils for the Cd metal sorbed. Cadmium sorbed was extracted by IN‐NH₄C1 followed by 0.1N HC1, and the fraction remaining in the soils was considered specifically sorbed Cd. This fraction also followed a linear sorption isotherm, and was around 30% for the four soils studied. The sorption order for the amount of specifically sorbed Cd showed that the Boomer soil (kaolinite‐iron oxides) had the lowest affinity for specific sorption of this metal. This was taken as evidence that kaolinite and iron oxides have a lower capacity for retaining cadmium through specific sorption mechanism(s) than the materials present on the other soils (2:1 layer silicates and humic substances). The existence of specific mecha‐nism(s) responsible by the sorption of trace quantities of Cd in soil solutions has important implications on soil‐plant relationships, Cd mobility in soil profiles and control of Cd activity in soil solutions.     

Aerobic and anaerobic burning alter trace metal availability in peat soils: evidence from laboratory experiments

As global warming becomes more pronounced, climate change and human activities are leading to frequent peat fire incidents. Fire plays an important role in the environmental distribution of trace metals in peat soils. In the current study, we collected peat soils from six peatlands of the Great Khingan Mountains in Northeast China, where wildfires have often occurred in recent decades. To investigate the transformation of trace metals in peat soils by fire, burning experiments at 250°C (light) or 600°C (severe) and under aerobic (AE, flaming) and anaerobic (AN, smouldering) conditions (AE250, AE600, AN250, AN600) were carried out in the laboratory to investigate the effect of different burning intensities on the distribution of Cu, As, Pb, and Cd in peat soils. The European Community Bureau of Reference (BCR) sequential extraction method for metal fractions was applied for partitioning four fractions (exchangeable, reducible, oxidizable, and residual). The results showed that AE600 significantly decreased the percentages of oxidizable Cu, As, Cd and Pb (Cu_oxi, As_oxi Cd_oxi and Pb_oxi) compared with those of the original samples, e.g., Cu_oxi decreased from 68.84% ± 12.76% to 15.82% ± 8.02% in peat under moss, which might result from organic matter decrease. Under AN250 conditions, the exchangeable As (As_exc) and Pb (Pb_exc) significantly increased by more than twice. Different burning intensities significantly changed the various fractions of Cu, e.g., more than 20% Cu_oxi transferred to exchangeable and reducible fractions as the temperature increased. Most of the available fractions of As transformed to residual As after burning. Our study suggests that the AE600 treatment increased the ecotoxicity and bioavailability of Cu, Pb and Cd in peat soils, while AN250 burning decreased the potential ecotoxicity of Cu, As, and Pb. Compared with lower temperature flaming burning (AE250), the ecotoxicity and bioavailability of Cu and Pb were greater in high temperature (AE600) conditions. Smouldering fires at both temperatures (AN250 and AN600) maintained a high potential ecotoxicity and bioavailability of Cu and Pb in peat soils.     

Phosphorus and trace metal dynamics in soils amended with poultry litter and granulates

Environmental sustainability of animal agriculture is strongly dependent upon development of approaches to minimize the potential environmental impacts of applying animal manures. The excess manure and its nutrients (primarily phosphorus) in intensive animal production regions may need to be exported to other areas to comply with increased regulations on manure management. In our previous study we generated a variety of granulated products from poultry litter to achieve export of excess litter from the southwestern Ozarks, AR, USA. Our objective in the present study was to determine the effect of the application of poultry litter and granulated litter products on phosphorus (P), arsenic (As), copper (Cu) and zinc (Zn) dynamics in two Arkansas soils (Dewitt silt loam and Hector sandy loam). Poultry litter and granulated products were mixed with the surface horizon (0–15 cm) of soils at two application rates: P‐based (100 kg total P per hectare) and N‐based (160 kg plant‐available N per hectare). Soil–litter mixtures were incubated at 25 °C for 21 days. Sub‐samples were removed at 1, 7 and 21 days to determine the solubility and availability of P, As, Cu and Zn in soils. Results suggest that when litter was applied at 100 kg total P per hectare, contents of P, As, Cu and Zn were significantly greater in the soils amended with litter and granulated products than in the control (soil alone). However, the contents of P, As, Cu and Zn did not significantly differ in the soils amended with either normal litter or granulated litter products at total P or plant‐available N‐based application rates. This suggests that poultry litter granulation is a sound management practice that can be used to reduce concerns with fresh litter transport and potentially improve P and trace element balances in intensive poultry production regions, especially when applied on a plant‐available N basis.     

Lithium toxicity in plants

Abstract

The toxicity of Li to three plant species was studied to determine if there were interactions with other elements and to determine if a chelating agent modified Li toxicity. Bush beans (Phaseolus vulgarls L. C.V. Improved Tendergreen), grown in solution culture, were sensitive to 0.5 X10^‐3Li which resulted in 10 μg/g in leaves, 48 in stems, and 24 in roots. Higher concentrations of Li produced marked reductions in plant yield accompanied by increased Li concentrations in leaf, stem, and root tissues. For most treatments, root concentrations of Li were lower than those in shoots, but those in stems were higher than those in leaves. Higher levels of Li decreased Zn in leaves, increased Ca in stems, and generally increased Fe and Mn in all plant tissues. Ethylenediamine tetraacetic acid (EDTA) resulted in slightly increased Ii levels in leaves, stems, and roots. Bush bean plants were injured slightly with 25 μg Li/g of Yolo loam soil applied as LiCl; 50 μg Li/g soil caused more severe injury. Leaf concentrations of about 200 μg Li/g resulted in significant yield reduction and around 600 μg//g of leaves resulted in severe toxicity. There were some interactions of Li with other elements which resulted in an increase of them in both leaf and stem tissues. Barley plants (Hordeum vulgare L. C.V. Atlas 57) were severely stunted when grown with 500 and 1000 μg Li/g soil as Li oxalate. Increasing the soil pH even further with lime and decreasing it with S had no influence on the toxicity. Shoot concentrations of Li ranged from 800 to over 2000 in the various treatments resulting in severe disruption of the Ca and K balance. Leaf concentrations of Li were higher than those for stems in cotton (Gossypium hirsutum L. C.V. Acala 442). Cotton was tolerant of a leaf concentration of 587 μg Li/g. High levels of Li increased concentrations of several elements in cotton leaves and in stems. Cotton leaves accumulated more Li than did bush beans.     

Trace metals in two garden products derived from sewage sludge

Abstract

Yields were decreased in soybean (Glycine max L. C.V. Hawkeye), mint (Mentha viridis L. ), and barley (Hordeum vulgare L. C.V. Atlas 57) when grown in 50% Yolo loam soil and 50% of either of two commercial garden sewage sludge products. The trace elements Zn, Cu, Mn, and B were elevated in plants grown with the high‐level amendments. No Cd and little Ni were detected in shoots.     

Excess trace metal effects on cotton: 4. Chromium and lithium in Yolo loam soil

Abstract

Two cultivars of cotton (Gossypium spp) were grown in Yolo loam soil in a glasshouse to determine phytotoxicity effects of Cr and Li and possible interactions with other metals. The Cr at 100 μg/g soil had no adverse effects on either cultivar studied. A Cr increase was not observed in either stems or leaves. Both cultivars tolerated 25 and 50 μg Li/g soil. The 50 μg Li/g soil resulted in leaves of Acala SJ‐2 with 432 μg Li/g leaves and 720 in Giza 45. The 100 μg Li/g soil resulted in 74% and 87% leaf yield reductions in Acala SJ‐2 and Giza 45 respectively. Leaf concentrations of Li respectively were 1950 and 1850 μg/g. Except at the highest level of Li, leaves had higher concentrations of Li than did roots. The Cr and Li resulted in some plant metal interactions.     

Some effects of fly ash (from coal burning) on bush bean plants grown in solution culture

Abstract

Bush bean plants (Phaseolus vulgaris L. C. V. Improved Tendergreen) were grown for 14 days in 3700‐ml solution cultures with varying application rates of fly ash from a coal burning plant in California. Plants were also grown in a solution culture experiment in the presence of tiie chelating agent DTPA (diethylene triamine pentaacetic acid) and also in solutions acidified with HCl. The latter treatments were to determine if metals in the fly ash could be made more available to plants. The higher levels of fly ash (5 to 10 g/3700 ml) resulted in increased Ca, B, Si, Sr, and Ba in leaves, stems, and roots. No plants, however, appeared to have an excess of trace metals. In another experiment DTPA and HCl amendments failed to increase greatly the availability of trace metals from the fly ash in solution culture except for Zn. In this experiment the fly ash was the sole source of Ca and plants were deficient in Ca because insufficient fly ash was added. The fly ash resulted in increased Zn, Ca, Fe, Mn, B, Al, Si, Ti, Mo, Li, Sr, Ba in leaves, stems, and roots and increased V, Co, and Ni in roots. There was 3 to 4 μg/g Sn and 0.6 μg/g Be in the roots of plants grown with fly ash. In another experiment, fly ash supplied all the Ca necessary for plant growth without decreased yields resulting from any trace metal.     

Growth of apple seedlings on sludge‐amended soils in the greenhouse

Abstract

Open pollinated ‘York Imperial’ apple (Malus domestica Borkh.) seeds were germinated and grown for a period of 7 months in: (1) sand with complete nutrient solutions added; (2) limed and unlimed soil, (3) limed and unlimed soil amended with two different sewage sludges at rates of 25, 50 or 100 dry kg ha^‐1. A third composted, lime stabilized sludge was added either sieved or non‐sieved (to remove wood chips) at the same rates. The sludge materials used were: (1) a high metal, composted sludge from Baltimore, MD (BALT); (2) a high Cd sewage sludge (CITY) and (3) a low metal, composted sewage sludge from Washington, D.C. (DC).

Germination was unaffected by treatments. After 7 months, the best growth was obtained from the sand plus nutrient solution media. Two of the three sludge materials increased seedling growth over that of the soil, either limed or unlimed. The BALT compost treated soils produced the lowest growth, particularly when unlimed. Elevated tissue metal levels indicated that Mn, Zn, Cu and Ni were the probable causes of reduced growth noted from the BALT compost treatment. The use of soil with or without low metal sludges as media for early apple seedling growth when compared to standard sand culture is not recommended.     

Trace metal leaching in a spodosol irrigated with tomato packinghouse wastewater

Tomato packinghouse wastewater is often applied to land in Florida, but the sandy soils, low levels of organic matter, shallow groundwater and abundant rainfall present favourable conditions for leaching of wastewater‐borne trace metals. We investigated the leaching of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) from a sandy siliceous, hyperthermic Oxyaquic Alorthods packed in two distinct soil horizons (Ap and A/E) in 12 polyvinyl chloride soil columns (30 cm internal diameter × 50 cm length). Thirty leaching events were conducted by daily applying tomato packinghouse wastewater at low (0.84 cm/day), medium (1.68 cm/day) and high (2.51 cm/day) rates for 30‐days period. Control treatment received de‐ionized water at the same application rate as the medium treatment (1.68 cm/day). Application of wastewater at three rates did not affect the mean concentrations of Cu in leachate (0.19–0.2 mg/L) because of retention of Cu in the soil profile. However, leachate Zn concentrations were twice as much (0.3–0.32 mg/L) following wastewater application than for the control (0.13 mg/L) treatment. Leaching losses of Cu and Zn were smaller with the medium wastewater treatment (similar to control treatment) than for the high wastewater treatment. Concentrations of Cu and Zn at the 50 cm soil depth were much less than the drinking water standards, suggesting a minimum risk of groundwater contamination under fields to which wastewater was applied. Our results imply that tomato packinghouse wastewater can be safely land‐applied at 1.68 cm/day to Florida’s Spodosols under vegetable production without concerns of significant trace metal leaching.