TRACE ELEMENTS ACCUMULATION IN WALNUT GROWING ON RESIDENTIAL AREAS IN UKRAINE

The Walnut (Jugland regia L,) is wide spread on the territory of Ukraine, This big fine tree is grown both in orchards, park, in roadside green belts, It is popular for high nutritive value of their nuts, bactericidal properties of leaves, volatile production. Pilot investigation has been held to reveal trace elements accumulation in walnut depending on traits of environment in urban and rural areas, Leaves and nuts of walnut have been sampled in 2003-2004 September in different parts of the country, Leaf, kernel and nutshell have been ashed and analysed (ESA) separately, Main results of investigation are as follows: accumulation of phosphorus, copper, zinc and lead in kernel estimated; probably nutshell serves as a barrier for strontium accumulation in kernel; lead concentration is higher in kernel of walnut growing along motorway and may can reach sanitary limit; zinc concentration inversely is higher on rural areas; arsenic has been find in matter sampled near railway roads, In future more detailed investigation of Walnut could make it possible to estimate the walnut as an instrument for pollution monitoring and control.


INTRODUCTION
The Walnut (Juglans regia L.) is a big tree reached 25 m in high with power crone and thick stem (trunk), Leaves are alternating odd-pinnate with ovate green laminae. A fruit of the walnut is a drupe with green fleshy outer covering, hard light brown inner part (nutshell), and edible kernel inside with 2-5 partitions, The walnut's system of roots is high developed and power if soil conditions are good enough and primary root can reach 4 m in depth and secondary roots 20 m in wide with thorns near the earth surace, Traits of the root system provides for walnut's ability to prevent soil erosion [1 -5 l , °W alnut trees are destroyed by the frost at the temperature of -(25-28 ). The walnut is wide spread on the territory of Ukraine, It is popular for high nutritive value of their nuts, bactericidal properties of leaves and their ability for volatile production. This big

METHODS OF INVESTIGATION
Sampling of walnut trees have been held in Autum of years 2003-2004. Taking of sampls has been provided on the urban and rural areas in oblast's of Kharkiv, Lugans'k, Donets'k, Sumy, Hmelnitsky, lvano-Frankivs'k, Kherson, the Crimea Autonomic Republic. The distance between the sampling point and the railway or motor road has been taken into consideration. Matter from 12 points of sampling has been used for investigation. In the process of samples preparation for analyzing nuts, it was divided on nutshell and kernel to be analyzed separately, The weight of a standard sample was 20 g. Matters of samples (kernel, nutshell, leaves) have been dried and ashed at the temperature not higher then 500 °C (to condition of "the white ash") and for results of weighting the content of ash in organic matter has been calculated.

Content of trace element in different parts of plants has been detenninated using EAS method of plants investigation [6 ].
Obtained results have been analysed with applying methods of mathematical statistics,

RES UL TS AND DISCUSSION
The results of mathematical treatment of the obtained data are exposed in the table I,   4), but in kernel its content may be estimated as normal probably for the nutshell activity as a screen. Besides arsenic concentration (5-10 mg/kg), it has also been detennined in some walnut samples taken near railroads.

Results of pilot investigation concerning trace elements concentration in Walnut trees m urbanised territories can be summarized as follows.
I -Accumulation of copper, zinc and lead in kernel of the walnut has been estimated. 2 -Lead concentration is higher in kernel of walnut growing in urban areas along motorway and may reach sanitary limit. 3 -Zinc concentration in kernel of the nut inversely is higher on rural areas; 4 -Arsenic has been finding in matter of the walnut sampled near railway roads.

-High concentrations of lead and strontium in leaves of the walnut have been detennined.
For strontium this process has been known earlier [8,9]. 6 -Nutshell probably could serve as a barrier for too high strontium concentration in kernel 7 -More detailed investigation could make it possible to estimate the Walnut as an instrument for pollution monitoring and control.