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1.
Tailing ponds pose environmental hazards,such as toxic metals which can contaminate the surroundings through wind and water erosions and leaching.Various chemical and biochemical properties,together with extractable and soluble metals were measured five years after reclamation of a polluted soil affected by former mining activities.This abandoned mine site contains large amounts of Fe-oxyhydroxides,sulphates,and heavy metals.As a consequence,soils remain bare and the soil organic matter content is low(< 3 g kg 1).Marble waste,pig manure and sewage sludge were applied in 2004.Plant cover and richness,and soil chemical,biochemical and biological parameters were analysed five years later.Results showed that all soil biochemical properties as well as vegetation cover and richness were higher in treated soils than in the untreated contaminated plots(control),although organic matter,pH values and extractable metals concentrations were similar among treatments.Soluble cadmium and zinc were lower in the amended plots than in control.As a general pattern,soil amended with pig manure showed higher values of most biochemical properties compared to sewage sludge application,while the doses did not have a great effect,being only significant for β-glucosidase,phosphodiesterase and arylsulfatase.Significant correlations were found between vegetation cover,richness and soil biochemical properties,suggesting a high interdependence between plant colonization and reactivation of biogeochemical cycles during five years.This study confirms the high effectiveness of an initial application of the amendments tested to initialize the recovery of ecosystems in bare mine soils under Mediterranean semiarid conditions.This research also shows the high sensitivity of certain biochemical properties in order to evaluate soil quality and reactivation of nutrients cycles in reclaimed mine soils.  相似文献   

2.
粤北铅锌矿区土壤生态系统微生物特征及其重金属含量   总被引：1，自引：0，他引：1  
粤北大宝山金属矿产资源的开发给生态环境带来了严重危害。对该铅锌矿区土壤的微生物特征进行研究。结果表明:五节芒植物中的元素含量表现为Zn>Pb>Cu>Cd,Zn与土壤元素的相关性最为显著,其次为Pb。与对照土壤相比,矿区土壤的微生物基础呼吸作用增强,但微生物生物量却显著降低,微生物生理生态参数Cmic/Corg、qCO2值明显升高。随着矿区土壤的重金属含量增加,矿区(1#、2#)土壤的生化作用强度明显下降,生化作用表现为与土壤重金属含量呈显著负相关。与非矿区(6#)土壤相比,其中土壤氨化作用、硝化作用、固N作用和纤维素分解作用强度分别下降43.19%～70.01%,70.71%～92.02%,58.54%～87.76%和55.00%～79.60%。生化作用表现为与土壤中重金属含量呈显著负相关。土壤微生物活性下降是矿区土壤生态系统遭受破坏的重要标志之一,也是矿区土壤微生物生态演变的重要因素之一。土壤微生物活性降低削弱了矿区土壤中C、N营养元素的循环速率和能量流动。  相似文献   

3.
Sewage sludge treated with 15% bentonite, vermiculite or biochar was evaluated as a soil amendment in comparison to limed and untreated sludge. Seven treatments were established to two soils, an acid and an alkaline, in three replications, i.e. 2% addition of sludge treated with bentonite, vermiculite, biochar and lime and application of 2% untreated sludge, inorganic fertilization and no sludge or inorganic fertilizers (control). Then, the soil treatments were used in a pot experiment with perennial ryegrass (Lolium perenne L.) as a test plant. Sludge treated with the clay minerals or biochar improved pH of the acid soil and significantly increased organic matter and available nutrients of both soils compared to control. Although no salinity or sodicity hazard was evidenced, the initial salinity of acid and alkaline soil increased by four-eight and two-three times, respectively, upon addition of all sludge treatments, especially that of untreated sludge. Moreover, soil available zinc (Zn) increased by four-eight times. Soil application of sludge treated with the clay minerals or biochar increased the total aboveground biomass yield of ryegrass in the acid and alkaline soil by 133%–171% and 72%–88%, respectively, compared to control and enhanced nutrient uptake by plants. Furthermore the microbial metabolic quotient indicated lack of low pH and heavy metal stress with addition of sludge to the acid soil. After three harvests of ryegrass, the residual effect of sludge on pH of acid soil and salinity, available phosphorus (P), Zn and boron (B) of both soils still persisted. Thus sewage sludge treated with 15% bentonite, vermiculite or biochar could be applied to soils at a rate of 2% (≈80 Mg ha−1) to serve as soil amendment and fertilizer for grasses and pasture species; however, caution is needed regarding possible P build-up, Zn phytotoxicity and salinization risks.  相似文献   

4.
A 32 ha tailings pond used for the disposal of pyritic mine waste was examined after a period of eight years to determine the success of the rehabilitation plan used to revegetate the site. This was achieved by examining both the vegetation cover and the quality of the topsoil in order to determine the effect of the tailings. A number of floristic habitats were identified within the site indicating that succession had occurred since revegetation of the area with metal-tolerant grass species. Four main habitats were investigated: leguminous, grass, gorse and low canopy. The soil layer in Shelton Abbey was 25–30 cm deep and contained levels of nutrients and metals comparable to those found in unpolluted soils. It was followed by a 20–25 cm layer of mixed soil and tailings, followed by the tailings only. The tailings retained elevated concentrations of metals indicating their unsuitability for growth of unadapted plant species. Vegetation from all habitats, analysed both in the summer and winter, contained higher levels of iron only compared with vegetation grown on unpolluted soils. Metals do not appear to be significantly leached from the tailings either into the soil or into surface and ground waters, and have not been accumulated to above normal levels by plant uptake. The rehabilitation protocol used at the site appears to have been successful. However, the site needs to be managed on an on-going basis to ensure the integrity of the bund and revegetated area. © 1998 John Wiley & Sons, Ltd.  相似文献   

5.
Legislation requiring the rehabilitation of new opencast coal mines came into effect in New South Wales, Australia, in 1973. Mining companies now stockpile original topsoil which is later spread with fertilizer over re-shaped overburden and waste carbonaceous material. Problems in successfully revegetating new surfaces are exacerbated by the thinness and infertility of natural soils, which are deficient in phosphorus and moderately acid. Revegetation has not been successful on untreated mine waste and overburden. This study provides a general overview of some aspects of post-rehabilitation soil chemistry and vegetation on these soils. A limited number of samples, collected from three mine sites having different rainfall and varying ages of rehabilitated areas, were tested for pH, EC, organic carbon, total phosphorus and available aluminium. Rehabilitated areas were all characterised by very low levels of total phosphorus, neutral pH, and variable and relatively low organic carbon, and some showed aluminium toxicity. Heavy application of gypsum at one of the steeper sites was associated with acid pH, high EC values, low total P, Al toxicity, some soil erosion and little plant cover. Except for this site, the variable vegetation cover at the sites studied seemed adequate for long-term re-establishment, despite serious weed invasion at some non-studied sites, soil loss on newly re-formed surfaces, and generally poor natural and rehabilitated soils.  相似文献   

6.
Mine tailing soils created from the copper extraction in Touro Mine (Northwest Spain) are very degraded both physically and chemically. Three plots in this mine tailing were amended with Technosols in different proportions in each one to know if this mixture improved the physico-chemical characteristics of the mine soil and contaminated it with heavy metals. The Technosols were made of organic wastes, including mussel residues, wood fragments, sewage sludges and paper mill ashes. An unamended area was used as a control soil. Pseudototal and diethylenetriaminepentaacetic acid (DTPA)-extractable contents of Al, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined in soil samples. The untreated soil had significant limitations for vegetation growth. All the Technosols improved the properties of the mine soil by increasing organic carbon and pH value, but they added Ni, Pb or Zn to the soil. It is advisable to check whether the heavy metal concentrations of the wastes are hazardous or not before adding to soils. It is also necessary to study the effect of these wastes over time and in more areas to conclude if they are actually favourable to restore degraded mine soils.  相似文献   

7.
An increasing proportion of recycled fibres are used in paper industries. Removing the ink, clay, coatings and contaminants from paper waste in order to produce recycled fibres creates large amounts of deinking paper sludges. The preparation of biochar from pyrolysis of this waste and its use in soil remediation contaminated with heavy metals could be an interesting valorization alternative. Our aim was to study the influence of biochar from deinking paper sludge (HP) pyrolysis in the treatment of Zn‐polluted soils. Three different soils contaminated with 2000 mg Zn kg−1 were amended at a rate of 10% with deinking paper sludge and deinking paper sludge biochar prepared at three different temperatures (300, 400 and 500 °C). Soils were incubated under laboratory conditions, and soluble Zn was measured. The addition of biochar reduced the amount of mobile Zn. Finally, Zn solubility decrease was more pronounced for biochars prepared at a higher temperature. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
采用盆栽试验方法,研究了污泥改良锰矿尾渣对紫茉莉（Mirabills jdapa）、青葙（Celosia argentea）、一串红（Salviasplendens）和鸡冠花（Celosia cristata）4种花卉植物生长及其富集铅、镉、锌和锰的影响。结果表明,添加污泥增加基质的EC值、总氮、总磷、总钾和有机质含量,而降低铅、镉、锌和锰含量。紫茉莉与青葙生物量、株高和根长大于一串红和鸡冠花。紫茉莉根部铅、镉和锰含量分别为3110．93～4189．16、300．28～399．16和31100．93～36809．77mg·kg-1,都远高于其地上部分含量。青葙根部铅含量超过1000mg·kg-1,而其地上部分含量少;其地上部分镉和锰含量分别为322．13～441．88和21888．54～26511．31mg·kg-1,都大于其根部含量,青葙具有镉和锰超富集植物的特性。污泥改良锰矿尾渣促进这4种花卉植物生物量、株高和根长增加。除紫茉莉锌含量外,添加污泥改良锰矿尾渣增加这4种花卉植物的铅、镉、锌和锰含量。在锰矿尾渣污染区进行植物修复时,采用紫茉莉、青葙和添加污泥强化植物修复效率可行。  相似文献   

9.
Earthworms are important members of the decomposer food web in a wide range of sites. Previous field investigations on the development of earthworm populations of mine soils in the Lusatian coal mining region, Germany, have shown quite small population densities in quaternary sands and less or even no earthworms present in sandy soils derived from tertiary deposits. The aim of the present investigation was to improve the development of earthworm populations in mine soils from tertiary deposits by applying various types and amounts of organic waste residues, such as sewage sludge, composted sewage sludge, and green waste derived compost. Additionally, we were interested in the stimulation effect of organic waste materials on parameters of earthworm activity, such as food consumption and burrowing activity. The investigations were carried out in field mesocosms and laboratory experiments (microcosms; observation cages). In general, the population density, fresh biomass, food consumption, and the burrowing activity of earthworms were significantly improved by the application of the various organic waste materials compared with mineral fertilizers. Fresh sewage sludge in addition to composted sewage sludge were found to be the most favourable organic waste residues compared with green waste derived composts. The addition of brown coal sludge to sewage sludge did not reduced the stimulation effect. There was considerable variation in the population structure of a defined earthworm community which was exposed in the mesocosms during a two year period in relation to the types and amounts of the organic waste materials applied.  相似文献   

10.
Background: The fertilizer value of phosphorus (P) in waste products relies heavily on its availability to the subsequent crop. Aim: We studied the link between extractable P in waste products and apparent P recovery (APR, i.e., difference in plant P uptake between P amended and un‐amended soils divided by the amount of P added) using spring barley grown on three sandy soils. Methods: The products included sewage sludge, biomass ash, struvite, compost, meat and bone meal, biochar from sewage sludge, and industrial sludge. Soft rock phosphate and triple‐superphosphate (TSP) were included for comparison. Availability of P was characterized by extraction with water and solutions of sodium bicarbonate, citric acid, oxalic acid, hydrochloric acid, ammonium acetate, ammonium fluoride and anion exchange resin membranes. TSP was used to establish mineral‐fertilizer‐equivalents (MFE). Water and bicarbonate extractions were also applied to products incubated with soil before extraction. Results: The APR ranged 26 to 31% for TSP and 0 to 30% for waste products. APR correlated most strongly with bicarbonate extractable P. The correlation increased when products were incubated with soil before extraction. Conclusions: We conclude that bicarbonate extraction is a good indicator of potential P availability. However, interactions between waste products and soil properties modify P availability.  相似文献   

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