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Forest humus type governs heavy metal accumulation in specific organic matter fractions
Soils have the potential to accumulate heavy metals and the capacity to do so is strongly related the properties of each soil. Soil organic matter is a key factor in the retention, release, and bioavailability of heavy metals, and here we have determined the accumulation of heavy metals in various types of humus in the Rybnik Forest District in southern Poland. In a novel approach, we analyzed relationships between heavy metals within soil organic matter fractions and evaluated the role of organic fractions in mediating metal mobility. Specifically, we tested whether (i) the type of forest humus determines the heavy metal accumulation; (ii) heavy metals accumulation is associated with soil organic matter fractions; and (iii) heavy metals have an inhibitory influence on biochemical properties especially enzymes activity in different humus types. Four types of humus were sampled (mor, moder, moder-mull, mull), physically fractioned, and a number of chemical and biochemical properties were analyzed. Calculated geo-accumulation index (Igeo) and enrichment factor (EF) confirmed soil pollution with Cd and Pb. The type of humus differed in the accumulation of heavy metals, which is associated to the variable concentration of organic matter remaining at each decay class. We found no relationship between enzymatic activity and heavy metals concentration except for a positive correlation between urease activity and nickel concentration. Considering wider evidence, we propose a biogeochemical link between nickel deposition and the production of soil-borne urease in these forest soils
Heavy metals and nitrogen in mosses: spatial patterns in 2010/2011 and long-term temporal trends in Europe
Naturally-occurring mosses have been sampled across Europe to monitor
the deposition of heavy metals and nitrogen from the air. This survey has been
repeated at five-yearly intervals since 1990 for heavy metals and since 2005 for
nitrogen. In 2010/2011, mosses were collected at ca. 4,500 sites in 25 countries
for heavy metals and ca. 2,400 sites in 15 countries for nitrogen. In general, the
lowest concentrations in mosses were found in northern Europe for both heavy
metals and nitrogen. The highest concentrations of heavy metals were often
observed in south-eastern Europe, whereas the highest concentrations of
nitrogen were found in parts of western and central Europe. Europe-wide the
concentration of lead (77% decline), vanadium (57%), iron (52%) and cadmium
(51%) has declined the most since 1990, whereas the concentration of copper
has declined the least (11% decline). Since 1995, the concentration of arsenic and
mercury has declined by 26% and 23% respectively. The nitrogen concentration
in mosses has hardly changed since 2005
Soil heavy metal contamination and acid deposition: experimental approach on two forest soils in Hunan, Southern China
In 1985, a tailing dam collapsed in Hunan province (southern China) leading to soil contamination by heavy metals from the tailings waste. Moreover, acid deposition becomes more and more serious in this area. In this context, two forest soils (a red soil and a yellow red soil, typically and commonly found in southern China) were collected from Hunan. The objectives are (i) to determine releases and changes in speciation fractions of heavy metals (especially Cd, Cu, and Zn) when the soils are contaminated with heavy metals and affected by simulated acid deposition, and (ii) to study effects of soil heavy metals and acid deposition on releases of soil Ca2+, Mg2+, and Al3+. The soil samples were soaked in the solutions of CdCl2, CuCl2, and ZnCl2 for 15 days to make contaminated soils containing 200 mg kg1 of Cd, Cu, and Zn. Then the contaminated soils and the original soils were extracted with five simulated acid deposition solutions (pH ranged from 5.6 to 3.0 and total dissolved salts increased). The experimental results indicate that acid deposition leads to great releases of soil heavy metals due to complicated soil chemical processes, mostly cation exchange and partly dissolution of minerals at pH lower than 4.2. These released heavy metals come mainly from soil exchangeable pools and other labile fractions. Releases of heavy metals are closely controlled by pH values or, in some cases, total cation contents in acid deposition; meanwhile, concentrations of heavy metals are negatively related to the relevant pH values in soil equilibrium solutions when pH values are in a range of 4.2–5.1. From the point of view of heavy metal releases, Zn is the most sensitive to acid deposition, followed by Cd and Cu. Compared with the original soils, the contaminated soils could probably release more base cations Ca2+ and Mg2+ and less Al3+. Greater amounts of Cd, Cu, Zn, and Al released from Soil B show that this soil is more sensitive to acid deposition, and we could expect serious environmental contamination in Soil B area if mining activities and acid deposition are not under control in the future
Assessment of heavy metals in urban highway runoff from Ikorodu expressway Lagos, Nigeria
The distribution of heavy metals in the urban high way run off from Ikorodu expressway of Lagos was
studied between March to May, 2004.The heavy metals studied include Pb, Cu, Cr, Zn and Cd. The levels
of these selected heavy metals were determined using Atomic Absorption Spectrophotometer (Mscientific
200 Model). Trends in the heavy metal from the runoff showed significant variations between
the months were values recorded in the month of April showed high values. Statistical analyses
showed different mean levels of these heavy metals assessed at the five collecting points. The
distribution shows Zn > Pb > Cu > Cr > Cd. Zn recorded the highest concentration levels between (53.4
± 35.5 - 107.5 ± 80.4 μg/l), while Cd levels (ND - 6.00 μg/L) were the lowest. However, the results obtained
falls within the permissible limits of FMENV effluents limits, FHWA and WHO standards of water for
domestic use
The cupric complexes of glycine and of alanine
The following report is the first of a projected series of studies of the physical chemistry of the compounds of the heavy metals, particularly of copper and of iron, with substances of biological importance. These studies are invited by the accumulation in recent years of examples of the importance of the heavy metals in biological chemistry
THE INFLUENCE OF MERCURY POLLUTION ON THE GROWTH OF BIO-INDICATOR PLANTS
Heavy metals are found naturally in the earth, and become concentrated as a result of human
caused activities. Common sources are from mining and industrial wastes, vehicle emissions, lead-
acid batteries, fertilisers, paints, treated woods, aging water supply infrastructure, and microplastics
floating in the world's oceans. Heavy metals enter plant, animal and human tissues via air
inhalation, diet and manual handling. Most of these chemicals including mercury, lead, cadmium
and their compounds are among the most common and highly toxic substances capable of
accumulation in living organisms. Heavy metals with excessive exposure to environmental objects
behave like ecotoxicants that negatively affect not only individual organisms, but also the
ecosystem as a whole
Influence of salts of heavy metals on the structure of epiphyseal cartilage
Among the known unfavorable influences on the skeletal bone, there is reaction on epiphyseal cartilage of bones under the influence of salts of heavy metals in the organism.
To study the morphological changes of epiphyseal cartilage of skeletal bones using salts of heavy metals (chrome, zinc and lead).
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/552
The Adsorbsi Cuper (II) by Sulfonated Sawdust
The existence of heavy metals is one of the major problems in the world. Increasing concentration of heavy metals because toxic in the soil, air, and water. Many methods have been developed to decrease concentration of heavy metals from water, for example by precipitation, evaporation, electrochemical and resin's consumption. However, the method is not effective because it requires high cost to operate. Therefore, the research for that materials are cheap and available. Biomaterial is one of the are used to reduce heavy metals from water (biosorption), for example sawdust. In this research, sawdust that used as adsorbent ion copper (II) must be modified by adding a sulfonate group by sulfonation process. The parameters tested are the activation time (sulfonation) and contact time. The optimum conditions of adsorption of Copper (II) by sulfonated sawdust in a single solution occurred at the sulfonation time 120 minutes and adsorption's contact time 60 minutes, the efficiency adsorption is 99.27%. From that conditions, the sulfonated sawdust is tested on the adsorption of Copper (II) in electroplating wastewater. The efficiency adsorption of Copper (II) in electroplating wastewater is 39.03%. This is occured because of the competition uptake's metals in the electroplating wastewater
INVESTIGATION OF PHYTOINDICATION EFFECTS DUE TO CADMIUM CONTAMINATION
Heavy metals are one of the most dangerous contaminants in the natural environment that
cause toxic effects in the cells of plants and animals. They are not decomposed in the environment
but consequently accumulated in the tissues of living organisms. Penetrating, for example, plants,
heavy metals can adversely affect the metabolic processes, which ultimately leads to a reduction in
yield and poses a threat of contamination by toxicants to the further food chain
Heavy metals partioning in three French forest soils by sequential extraction procedure
To know the concentration of heavy metal associated to chemical compounds is important to evaluate the environmental risks on soils, particularly regarding ion bioavailability. The relative mobility and strength of binding of heavy metals to the soil components can be studied using a sequential extraction procedure which provides a meaningful comparison between different soil profiles. The heavy metals partitioning bas been identified in three different french forest soils : one cambic podzol, one calcaric cambisol and one mollic andosol, using a new sequential extraction method. Results show that metal fractionation is metal and site specific. The water leaching phase does not contain any metals. The proportion of heavy metal leached in the exchangeable and the acid — soplhuabslee is significant for Cd. The residual
phase is important for Cr, Pb, and to a lesser extend for Ni. The organic matter fraction is dominant for Zn and Cu. Thus, the considered heavy metals are mainly bounded to iron oxides, to the organic matter and to the mineral residue. The order of heavy metals availability in the three soils would be : Zn>Cd>Cu>Pb>NiL&egatd;C r.i sotopes in some extracts of the extraction procedure corroborate the anthropogenic inputs for two soils. These both infomations allow to trace the origin, the mobility and the distribution of Pb in the soil
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