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1.
Reclamation and revegetation of coal combustion products (ash) are often complicated by high concentrations of metals. The effects of manure and soil additions on the extractability and plant availability of Pb, Cd, and B were examined in ash reclamation plots located in eastern Kansas. Concentrations extracted from the ash by ammonium bicarbonate DTPA were strongly affected by ash type and amendment, but were unaffected by crops. Plant uptake was affected by ash type and plant species and, to a smaller extent, by amendment. Extractable and plant concentrations were very high in some of the material, which was consistent with observed toxicity symptoms. Plant concentrations showed strong, positive correlations with extractable for Cd and B (r values 0.7 to 0.9), but plant Pb was negatively correlated with extractable concentrations (r = –0.66). Correlations were similar for plant uptake vs extractable for Cd and Pb but were much poorer for B.  相似文献   

2.
秸秆发电和气化残余物作为肥料在水稻生产上的应用研究   总被引:2,自引:0,他引:2  
秸秆发电和气化残余物(下称草木灰),其含有丰富的大量和中微量元素,如K、Ca、P、Mg、Si、Cu、Zn、B等,其中钾含量尤为丰富。而水稻是一种喜钾和硅的作物。将草木灰作为钾肥应用于水稻的生产上,一方面可节约生产成本,另一方面还可以改善大米的品质;但草木灰同时还含有重金属元素,过量的施入势必会带来土壤环境的恶化,本文通过分析土壤中和大米中重金属含量的变化,得出本试验中草木灰的施入不会引起环境的恶化;从生产成本和水稻产量与品质上综合考虑得出处理木灰1 50%替代化学钾肥和草木灰2 75%替代化学钾肥是最佳施肥处理。  相似文献   

3.
The clay mineralogical composition of soils on volcanic ashes from Mashū and Kamuinupuri-dake volcanoes, Hokkaido, which are rich in cristobalite, was determined using petrological, X-ray diffraction, differential thermal, and selective dissolution and differential infrared spectroscopic methods.

The cristobalite occurred in abundance in every size of fraction from coarse sand to clay and every soli from approximately 1,700 to 8,400 years old, and was concluded to be of igneous origin. The major clay minerals were allophanelike constituents and allophane with some layer silicates as the minor clay mineral, being similar to those of andesitic ash soils and different from those of volcanic ash soils containing abundant quartz. The quartz of volcanic ashes was presumed to bederived from the groundmass-equivalent portion of the ashes which had been formed from magma at a low temperature.  相似文献   

4.
A study was conducted to determine the extend of volcanic ash deposition and distribution in some soils of Malaysia. A total of 12 soil types of different geology and locations from Peninsular Malaysia and West Sarawak were collected and analysed for their physico‐chemical and dissolution analysis. All soils under study belonged to either the order of Inceptisols, Ultisols or Oxisol. They were acidic and had relatively low CEC and exchangeable bases. The Al saturation percent were higher in the Ultisols as compared to the Oxisols. Field and laboratory investigations, and the dissolution analysis comprising of the binary ratio, ferrihydrite percent and allophane content, suggested that the soils under study were highly weathered and non‐allophanic. The soils of West Sarawak, however, may contain a reasonable deposits of the volcanic ash materials, as shown by the higher pHNaF values of near 9.4, but other laboratory analysis were still not conclusive of the result.  相似文献   

5.
Liming and wood ash application are measures to decrease acidification of forests soils. The assessment of lime requirement can be based on that base saturation, which indicates a low risk of acid toxicity. Because of a wide spread Mg deficiency in Central European forests, Mg containing lime is normally applied. Ash from untreated wood is applied to decrease soil acidity as well as to improve K and P nutrition. In wood ash, K is the most soluble nutrient, follwed by Ca and Mg. The overall dissolution rate of lime applied to the forest floor is about 1t ha?1 a?1. After liming, soil solution alkalinity and Mg concentrations increase markedly, while changes of Ca, H ions and Al concentrations are less pronounced. After the application of wood ash, K concentrations increase due to the high K content and the high solubility of K in wood ash. After the application of a sufficiently high dosage of lime to the forest floor, the decrease of acidity in deeper soil layers may need decades because of the low solubility of lime. Nitrification and nitrate leaching induced by lime or wood ash may reduce their acid buffering efficiency.  相似文献   

6.
Abstract

To assess the mineral composition of plants growing in pure fly ash, grasses growing on lysimeters filled with alkaline, neutral, or acid fly ash were sampled several times in a 6‐year period. The samples were analyzed for elements essential for plants and animals as well as non‐essential, but environmentally significant, trace elements. Grasses were also sampled from ash dumps that were 20 and 30 years old. Fly ash is not a proper source of plant macronutrients N, P, and K. Plant growth on the alkaline fly ash can be influenced for some time by the high salinity of that ash. Grasses growing on unweathered fly ash were found to be high in Al, B, Co, Fe, Mo, Ni, Pb, and Se. Concentrations of several elements declined in time but levels of B, Fe, Mo, and Ni were still elevated in grasses on both fly ash dumps. All concentrations, except Al, were lower than toxicity levels for plants as found in literature. In plants growing on fresh fly ash concentrations of Mo, Pb, and Se can exceed the maximum tolerable levels for domestic animals. On weathered fly ashes (ash dumps) the Mo, Pb, and Se concentrations in grasses were below the maximum tolerable levels. Effects on animals by Mo in weathered ash may not be excluded because Mo concentrations can be high enough to induce Cu deficiency. Animals that feed on plants grown on fly ash could suffer from Ca, Mg, Na, and P deficiency.  相似文献   

7.
内蒙古包头市粉煤灰改良栗钙土化学性质的应用研究   总被引:3,自引:0,他引:3  
本文对包头市粉煤灰及该市准备绿化荒山的土壤进行了系统的土壤化学分析 ,结果表明 ,粉煤灰作为添加剂用于种草植树不会造成污染 ,而且可以补充当地土壤中某些营养元素的不足  相似文献   

8.
Abstract

A study was conducted to determine the influence of the volcanic ash deposition on the physicochemical characteristics of some soils of West Sarawak and to evaluate their suitability for some common crops. A total of seven common soil series of different geology and locations from West Sarawak were collected and analyzed for their physicochemical and dissolution analysis. For comparison, similar analytical procedures were conducted on selected volcanic ash soils of Indonesia and the Philippines. The Sarawak soils were classified as Inceptisol, Ultisol, and Oxisol. The soils were acidic and had relatively low CEC and exchangeable bases. The other laboratory analysis, however, were not conclusive in the results. The soils were evaluated for crops such as rubber, oil palm, rice, pepper, banana and tapioca. Most of these soils were rated as moderate (S2) to marginally suitable (S3), indicating insignificant contribution of volcanic ash into the fertility status of soils of west Sarawak regions.  相似文献   

9.
Abstract

Two commonly used methods of dissolution of heavy metals in soils and sediments for atomic absorption spectrophotomety (AAS) determination were compared. Dry ashing and subsequent dissolution with 3 N HCl in a block digestor was shown to give a better estimate of the aqua regia‐soluble fraction than wet ash digestion with a mixture of HNO3 and HClO4 acids using reference materials. But both methods extracted significantly less than the certified total contents of most metals.

In soils and sediments from SW Spain, the amounts extracted by the block heater method were generally greater than those obtained by wet ash digestion. In agricultural soils, highly significant differences were found between the amounts of Fe, Cu, and Zn extracted by both methods, but the significance decreases if both methods are used on soils or sediments from mining areas where metal contents are likely to be from recent deposits.  相似文献   

10.
Coal-fired power plants generate different types of ash residues and discharge small particles and vapors to the atmosphere. The ash residues which account for the major part of the byproducts are collected and stored as bottom ash, boiler ash, and fly ash, weathered ash and ash in lagoon. Analysis of water extracts of these residues will reveal how the nutrients are distributed in these residues and transported to aquatic systems. Equally interesting is the study of the downward movement of nutrients in soil treated with fly ash-amended organic compost when used as a manure for agricultural crops. In this work water extracts of different types of ash residues and eluates from descending ports of an experimental column of soil at different depths were also analyzed. Our results showed that there is considerable difference in the efficiency of removal and deposition of nutrients on different residues collected from the power plant and stored outside. Bottom ash was found to accumulate K, N, and S while Ca is enriched in ash from lagoon. Transition metals such as Zn, Mn, and Cu are concentrated in weathered ash. The concentration of most of the nutrients was found to decrease, in column experiments, as a function of depth and level to a depth of 80 cm.  相似文献   

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