The effect of motor vehicle emission on morphological and physiological characteristics of Rhus typhyna

Abstract

This article analyses changes of morphological indicators of Rhus typhyna L. in roadside plantations in Pavlograd, Ukraine. Experimental plots were placed at a distance from 1 to 130 m from the road. The control group of plants was at a distance of 1500 m from the highway. The plants were measured for length and thickness of annual sprout, number of leaves on it, the content of chlorophyll in leaves and accumulation of cadmium and lead in the tissues of these organs. It was found that, compared to the relatively clean area, the greatest decrease in the length and thickness of the annual shoots of the trees in the plantations, was for those which were at a distance of one metre from the highway. The number of leaves on a one-year shoot was significantly decreased compared to controls at all sites except those situated at a distance of one hundred and thirty meters from the path of moving sources of pollution. We evaluated the impact of transport emissions on the assimilatory apparatus. Within the twenty-five meter zone, there was an increase in the area of the leaf. The assimilation surface area was significantly decreased relative to values in the conditionally clean area only in the plants growing at a distance from one to five meters from the road. We identified a negative effect of the ingredients of motor emissions on chlorophyll content in leaves. The amount of chlorophyll a decreased with decreasing distance from the plantation to the road within the forty-meter area. Changes in the content of chlorophyll b lacked a clear pattern. The concentration of this pigment increased compared with control in a five-meter area, at a distance of twenty five meters it significantly decreased and did not differ from the indicators in the relatively clean areas, which were growing at a distance of forty and one hundred and thirty meters from the road. The amount of chlorophyll a + b in the leaves decreased compared to the control. Lead accumulated in these plant organs in the fortymeter zone. The amount of cadmium in the tissues of the leaf was significantly higher than the control values on plots located at a distance of twenty five meters. The strongest negative effects of phytotoxicants on susceptible plants occurred in plantations in the five-meter zone, which led to deterioration of the decorative quality of the plants.

The effect of vehicle exhaust emissions on morphometric and physiological characteristics of Rhus typhina

“…It should be mentioned that for 4-6 year old Rh. typhina plants at the distance of 25 m from the road changes of both total of the chlorophylls and their proportion were not reliably different from the values in the relatively clean zone (Dzhygan, 2017). Absence of reliable difference in the abovementioned parameters, in some authors' opinion (Bessonova, 2006) has great significance and is an adaptive reaction, using by which a plant adapts to the impact of xenobiotics.…”

“…typhina at the distance of twenty five and forty meters from the road surface. Growth inhibition of shoots of trees which grew in the conditions of environmental pollution with vehicle emissions has been determined by a number of authors (Rai, 2016;Dzhygan, 2017;Мamieva & Shirnina, 2017).…”