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Effect of Heavy Metal Pollution on Plants

Metals in the Environment

Trace metals occur as natural constituents of the earth's crust, and are ever present constituents of soils, natural waters and living matter. The biological significance of this disparate assemblage of elements has gradually been uncovered during the twentieth century; the resultant picture is one of ever-increasing complexity. Several of these elements have been demonstrated to be essential to the functions of living organisms, others appear to only interact with living matter in a toxic manner, whilst an ever-decreasing number do not fall conveniently into either category. When the interactions between trace metals and plants are considered, one must take full account of the known chemical properties of each element. Consideration must be given to differences in chemical reactivity, solubility and to interactions with other inorganic and organic molecules. A clear understanding of the basic chemical properties of an element of interest is an essential pre-requisite to any subsequent consideration of its biological significance. Due consideration to basic chemical considerations is a theme which runs through the collection of chapters in both volumes.

TABLE 2.14 METAL LOADING TO AGRICULTURAL WATERSHEDS IN
SOUTHWESTERN ONTARIO, CANADA. MEAN VALUES OF SIX WATERSHEDS.
DATA ARE g/ha-yr. (AFTER whitby et al. (1977)) Input CG Cu Ni Pb Zn Wet + dry
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Heavy Metal Pollution

The term "Heavy Metal" is somewhat imprecise, but includes most metals with an atomic number greater than twenty, but excludes alkali metals alkaline earths, lanthanum andactinides. Human civilization started with the accidental discovery of - especially Copper. Since then living organisms have taken long strides with the help of metals.

ABOUT THE BOOK The term "Heavy Metal" is somewhat imprecise, but includes
most metals with an atomic number greater than twenty, but excludes alkali
metals, alkaline earths, lanthanides and actinides. Human civilization started with
the ...

Heavy Metal Pollution Research

Recent Advances

Some 65 of the known 92 elements are metallic in nature. The term metal designates an element that is a good conductor of electricity whose electrical resistance is directly proportion to absolute 0T. In addition, metals share some distinctive characteristics such as high thermal conductivity and high density. Metallic elements are intrinsic components of the environment. Some 19 heavy metals of the known 65 metals are toxic in nature and cause a great threat to the living as well as non-living world, and so man is no exception. Actually toxic heavy metals are present at

Some 65 of the known 92 elements are metallic in nature.