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Fax: (0172) 26-59-40.Studies of the spectropolarization characteristics angular dependencies of radiation reflected by the plant leaves allow to investigate the mechanisms of reflected radiation flux formation: the specular reflection on the leaf surface, the singly and multiply scattering within leaf, the leaf pigment absorption, and the cuticle refraction of radiation going out from the leaf. The polarization characteristics are most sensitive to the changes of plant structure as compared with the other factors. We have discovered and theoretically substantiated a spectral shift of a maximum of the polarization degree angular dependence.The laboratory goniometer plant has been built up for receiving angular and spectral dependencies of the reflected radiation polarization characteristics on the base of production-type goniometer and spectropolarimeter GEMMA MC-04( M) (produced by Spectral Optics Technologies). Spectropolarimeter allows to record the radiation spectrum in the range of 400-830 nm within 0.4 sec for each of three polaroid positions (0, 45, 90 degrees relatively the entrance slit) and to transfer the data into computer in real time. The angular dependencies of polarization degree and polarization azimuth of the plant leaf reflected radiation as well as plant leaf scattering indicatrix were determined according to specially developed technique for the angle of incident of 70 degrees and the range of observation angle from 0 to 80 degrees. The potato leaves (Solanum tubefosum) were taken as the research objects. They have been grown in the plant pots and the test-tubes (21 hybrids and sorts in all). One potato sort or hybrid was differ from the other by it's morphology and anatomy as well as the index of immunity to Phytophthora infestans. Investigations were being made during the vegetation Season of 1995. The connection between radiation spectiopolarization characteristics and potato leaves biological parameters was received on the basis of regression, correlation and cluster analysis methods. It was shown that the ontogenetic development stage, sort (or hybrid) and some biological leaf parameters may be received from analysis of the spectropolarization angular functions.At present the urgent problem is the development of the methods of plant diagnostics. enabling to identify the initial forms of a potatoes for the selection and to diagnose illnesses at earliest vegetation stages. For the decision of this problem it is possible to use the methods and the equipment of the spectral analysis in visible and near IR-regiOn. We have developed the methods of the measurement and processing of potato spectral characteristjcs in the field conditions. We have carried out the large series of measurements on the experimental fields of Potato Research Institute of Belarus.For these purposes the series of the portable spectroradiometers on the area 350 -1050 nm with high characteristics were designed and made. This spectroradiometers are used in combination with Keynote 486 SLC PC and provide high-accuracy measur...

Pam Juan XXIII, i CI Tzjo (slnh Vlllavieiosr de O d C 28670 Madrid, Spain. email: busaoia.zc.itor@fis.ric.upm.n The paper addressss the unexpected increase and longer perriiience of omnc concentration in the atmosphere due to heavy trafftic during L e m " e t lale evening hours. Fig.1. shows the experimental results of omne meaucemats on the 24' of June and those obtained during the 30" of July 1999. The wealher conditions were similar charasterid by very low meteamlogical activity such as low velocity winds and average dcgrcc of to vehicle exhaust and to a very low extent lo wind uanspon of ozone from the industrial southcm region of Madrid. Measurement were made on several days brtwecn approximately I O a.m. and 10 p.m. The average standard deviation of 3% is equivalent to a measurement uncerminty of 0 4 ppb of ozone when m l l m averaging 100 pulses. Howwer, the major I , a differmcc between those two days was essentially due tu exccss vehicle traffic accompanying the summer holidays departures on the 30* of July. These tmffic conditions persisted until very late during the evening. A great aphasia was givcn to the concentration of omne monitored between 6 p.m and 10 p.m because one could think that L e dccrcasc in thc photochemical activity could be balanced by the larger anoml of NOn's in the atmosphere. AS a direct consequence, a much larger quantity of ozone indeed pelsisted in the atmosphae dcspite the low photoehcmical activity with a shin in the concentration profile towards later hours of the day The concentration of wmne wm more than 75 ppb at I O p.m while that ofthe 24 th of June roached only 25 ppb. Moreover, the rate ofchange of the 30 of July concenuatioo is much slower than that measured during the 24 th of lune. However, it is linown that the relation of volatile organic compounds (VOC) and NOx to 0 3 cmcmbBlim i6 not B simple o m I. Nevellhele,.it is well accepted that the amount of 0, is greater Bt smaller VOCMOx ratios. Therefore, the m h c m e n t of 0, concentration formed the 30* of July should b primarily a consequcncc of higher NOx conditions that originated from the excess vchicle exhaust which persisted until late in ihs evening. One ofthc main results of the present work is the finding of a significant increase in 0, conanbation due to traffic conditions, despite the IOW photochsmical activity. Thc prcsmt mosuremenw Rprexnt a step fonvard in L e undsstanding of amne dynamics. They will certainly stimulate liutbcr investigations in the dynamics of urban atmosphere pollution.