The article is devoted to the study of the leaves’ morphometric parameters of European white birch (silver birch, warty birch, East Asian white birch) (betula pendula roth (b. Verrucosa ehrh.) and Lombardy poplar (populus pyramidalis roz.). Plants respond very quickly to changing environmental conditions. Different types of plants are spread due to the nature of the soil cover. The harmful effects of vehicle exhaust on some plants are very severe, so these plants can be used to assess the state of the environment [4].
The article presents measurements of leaf area and petiole lengths from three different places in the settlement and compares them with a control sample located in the forest, where the influence of anthropogenic factors on plants is minimal. When performing the study, information was obtained that has practical application.
Introduction
Currently, large cities are the main human environment, therefore, it is relevant to study the environmental conditions of cities and the ecological situation with them. The level of air pollution in cities is changing for the worse every year.
The main air pollutants include motor vehicles, the amount of which is constantly growing. In 1900, there were about 6 thousand cars on the planet, but by the beginning of the 21st century the number of cars reached 500 million worldwide. Industrial enterprises also significantly affect air pollution. People living in large industrial cities have to breathe air saturated with harmful and toxic substances. Ferrous and non-ferrous metallurgy, chemistry and petrochemicals, construction industry, energy, and fuel industries have a particularly strong effect on air pollution. The pollution created by them negatively affects the state of the environment, and, therefore, jeopardizes the health of humans and other living organisms. In this situation, there is a need for measures to prevent environmental pollution [2].
One of the effective means of improving the environment of the city is landscaping. The role of green spaces in reducing the negative impact of the environment lies in their ability to improve the quality of the urban environment of natural and man-made origin. Green spaces really perform the function of temperature regulators, biofilters of pollutants and noise in urban conditions, have a landscape, sanitary and hygienic, recreational and aesthetic significance [3].
The main role of green spaces is to capture and neutralize gaseous toxins. At the same time, the plants experience very high loads, which leads to a disruption in the functions of metabolism, weakened plant growth, and decreased productivity. Plants with metabolic disorders are more susceptible to damage by diseases and pests, which can cause their death. Such a reaction of plants allows them to be used as indicators of the state of the urban environment and in monitoring air and soil pollution.
Plants respond very quickly to changing environmental conditions. Different types of plants are spread depending on the nature of the soil cover. The harmful effects of vehicle exhaust on some plants are very severe. Therefore, these plants can be used to assess the state of the environment (especially in hazardous areas of accumulation of decay products). The following signs of lesions in the vegetative organs of plants indicate an increased concentration of exhaust gases: drying of the tips of the leaves, discoloration of the leaf plate, the appearance of white spots on plants and a slowdown in plant growth [1].
The relevance of the research is to study the effect of atmospheric pollution using morphometric indicators of the vegetative organs of woody plants in urban populations, as they allow us to judge the ecological state of the study area.
The purpose of the research is to study the morphometric parameters of European white birch (silver birch, warty birch, East Asian white birch) (Betula pendula Roth (B. verrucosa Ehrh.) and Lombardy poplar (Populus pyramidalis Roz.) leaves in Severny, Belgorod region.
Objects of study are European white birch (silver birch, or warty birch, or East Asian white birch) (Betula pendula Roth (B. verrucosa Ehrh.), Birch family (Betulaceae) and Lombardy poplar (Populus pyramidalis Roz.), Willow family (Salicaceae).
The subject of research: morphometric parameters of European white birch (silver birch, warty birch, East Asian white birch) (Betula pendula Roth (B. verrucosa Ehrh.) and Lombardy poplar (Populus pyramidalis Roz.) leaves [5].
Materials and research methods
Samples of European white birch leaf (Betula pendula ROTH (B. verrucosa EHRH.)) were collected in May — June 2017 at four different areas
No. 1 — Sadovaya street;
No. 2 — Olympic Street
No. 3 — Oktyabrskaya street;
Dalnaya Street was selected as a control area.
Samples of Lombardy poplar leaf (Populus pyramidalis Roz.) were collected in July — August 2017 at four different areas:
No. 1 — Mir Street;
No. 2 — Olympic street;
No. 3 — Shosseinaya street;
Tsentralnaya Street was selected as a control area.
In total, 50 leaves were taken from each study area.
A caliper was used to perform morphometric measurements of European white birch and Lombardy poplar (measuring the length of the petiole). Some leaves were collected for the herbarium [3].
The electronic computer program “APFill Ink & Toner Coverage Meter” was used to determine the leaf area of European white birch and Lombardy poplar. A dense transparent film was placed on the scanner and the leaves of the test plant were laid out on it. The surface of the leaves were well dried. The leaf blades were scanned. The result was saved as a binary image (black and white). The resulting binary image was uploaded to the «APFill Ink & Toner Coverage Meter» program and the calculation of the area filled with ink expressed as a percentage. By calculations according to the formula:
S = I · A,
where ”S” is the area of scanned leaves; ”I” is the index of filling the sheet with ink, %; ”A” — is the area of A4 paper (297 · 210 mm²).
Got the area of scanned leaves.
The results were processed by methods of variation statistics. Using unpaired (two-sample) Student’s t-test, the significance of differences between the values of the characteristics of the comparison groups was determined [5].
RESULTS
Data for the determination of the area of the leaves of the European white birch and Lombardy poplar in the three areas in comparison with the control area are shown in table 1.
Table 1
The average length of the leaf of the European white birch and Lombardy poplar
|
average length of the European white birch petiole, mm2 |
average length of a Lombardy poplar petiole, mm2 |
|
|
Control area |
306,84 |
629,79 |
|
Area № 1 |
136,52 |
549,96 |
|
Area № 2 |
241,71 |
535,99 |
|
Area № 3 |
215,81 |
507,52 |
According to the degree of decrease in the average values of the area of the European white birch leaf can be arranged in the following row: Control area > Area 2> Area 3> Area 1. By the degree of decrease in the average values of the area of the Lombardy poplar leaf can be arranged in the following row: Control area> Area 1> Area 2> Area 3.
Data for the determination of the length of petioles of the European white birch and Lombardy poplar in the three areas in comparison with the control area are shown in table 2
Table 2
The average length of the petiole of the European white birch and Lombardy poplar
|
|
average length of the European white birch petiole, mm2 |
average length of aLombardy poplar petiole, mm2 |
|
Control area |
22,82 |
90,63 |
|
Area № 1 |
19,76 |
82,75 |
|
Area № 2 |
21,18 |
70,55 |
|
Area № 3 |
20,44 |
79,22 |
According to the degree of decreasing average values of the length of petioles of birch leaves, the pendulous can be arranged in the following row: Control area> Area 2> Area 3> Area 1. By the degree of decrease in the average values of the length of the petioles of the leaves of the Lombardy poplar can be arranged in the following row: Control area> Area 1> Area 3> Area 2.
Conclusion
- The length of the petioles and the leaf area of the European white birch (Betula pendula Roth (B. verrucosa Ehrh.) In Area No. 1 were lower than in the control. By the degree of decrease in the average values of these indicators, the studied plots can be arranged in the following row: Control area> Area No. 2> Area No. 3>Area No. 1.
- The average values of the measurements of the leaves of the Lombardy poplar (Populus pyramidalis Roz.) In area No. 2 had lower values in comparison with the Control area. By the degree of decreasing average values of the length of the petiole leaf petioles, the sections can be arranged in the following row: Control area> Area No. 1> Area No. 3> Area No. 2. The area of the leaves of the Lombardy poplar in Area No. 3 has lower values in comparison with the control. According to the degree of decrease in the average values of the leaf area of Populus pyramidalis, the plots can be arranged in the following row: Control> Area No. 1> Area No. 2> Area No. 3.
- Many affected leaves (spotting, chlorosis, necrosis) were observed in Area No. 2 in Betula pendula and in Area No. 3 in Populus pyramidalis, which may be associated with the most intense traffic.
The data obtained indicates that the most polluted areas in Severny are located on Shosseinaya street and Sadovaya street. Olympic street and Mir street are the cleanest streets [2].
References:
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- Bezuglaya E.Yu., Shchutstaya A. B., Smirnova I. V. Air pollution index and interpretation of measurements of toxic pollutant concentrations. Atmospheric Environment. V. 27 A. 1993 773–779 p.
- Cappon D. Indicators for a Healthy City. Environ. Manag. 1990. Vol. 1, № LP. 9–18 p.
- Dvoeglazova A. A. Ecological and biological characteristics of woody and herbaceous plants in the stands of the urban ecosystem of a large industrial center. — Ufa, 2009 21 p.
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