Analysis of chlorophyll "a", "b", and
carotenoids in leaves of oriental maple, biota,
common oak, and chestnut trees resistant to
harmful substances emitted by motor vehicles
in Tashkent city
Husan
Khodjibabayev
1*
,
Bahadir
Ismailkhodjaev
2
,
Malokhat
Abdukodirova
2
,
Dildora
Mavlyanova
2
,
Ibrokhim
Israilov
2
, and
T.
Samandarov
3
1
Research Institute of Environment and Nature Conservation Technologies, Tashkent, Uzbekistan
2
"Tashkent Institute of Irrigation and Agricultural Mechanization Engineers" National Research
University, Tashkent, Uzbekistan
3
Tashkent State Pedagogical University, Tashkent, Uzbekistan
Abstract
.
The work is devoted to the composition of the atmospheric air
on
the main streets, the level of traffic on these streets, the selection of
resistant species of phenol trees for growing ornamental trees, and the laws
of changing the number of pigments in these trees depending on the streets
and season in the Republic of Uzbekistan. At the same time, the types of
ornamental trees and their resistance to pollution from the pollution of
carbon dioxide, nitrogen oxides, and sulfur dioxide are mainly represented
by atmospheric air pollution.
1 Introduction
Nowadays, the growth rate of large cities depends on the growth of industrial enterprises
and motor transport, which requires many environmental issues.
Air pollution is mainly
caused by large-scale enterprises and motor vehicle emissions, especially on roads along
major highways, with motor vehicle emissions. In this case, pollutants are mainly exposed
to tree leaves. This is because photosynthesis and many other processes that allow the
growth of the leaves to take place in these leaves. Therefore, it is important to study the
degree of contamination of tree leaves with various contaminants
and to evaluate the
resistance of these toxic compounds to the green and yellow pigments involved in the
photosynthesis process in the leaves and their resistance to heavy metals. The volumes of
carbon dioxide absorption and oxygen production in different species of trees and leaves
vary. The air purification efficiency of ordinary juniper trees is 100 %, pine
–
164%, large
deciduous
–
254 %, oak
–
450 %, and Berlin poplar
–
691 % [1]. Decorative trees play an
aesthetic and social role in the environment and affect the quality of atmospheric air [2].
Trees in urban areas were planted to create favorable environmental conditions close to
optimal parameters corresponding to the so-called comfort zone. When the wind speed in
*Corresponding author:
xusanxodjibabayev@gmail.com
E3S Web of Conferences
401
, 02032 (2023)
CONMECHYDRO - 2023
https://doi.org/10.1051/e3sconf/202340102032
© The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative
Commons Attribution License 4.0 (https://creativecommons.org/licenses/by/4.0/).
the comfort zone is 2-6 m/s, and the relative speed is 30-70%, then the average temperature
is about 18-28°C.
Under favorable conditions, the noise should not exceed 45 dB (in the
evening) and 65 dB (in the afternoon). Remember that some factors determine comfort
conditions and depend on the degree of air pollution with gases and other particles [3]. In
nature, there are also artificial forests, parks, and even single trees, which significantly
improve the climate, creating a high level of comfort and hygiene. The green massif has its
own microclimate [4]. According to Roberta Baroni Fornasiero,
fluoride and many
fluorides are vital to humans and plants. Fluoride flora is found in highly industrial areas:
characteristic leaves are present on the leaves, the tip separating them from burns and
healthy, undamaged tissues. As a result of pollution, it is observed that the leaves of the
trees fall, the ends and edges of the leaves change, and they turn red and brown [5]. Air
pollutants are any gases or solid particles that can harm human health and the environment
at a sufficiently high concentration. It is known that air pollution occurs mainly from two
sources: natural
factors and a human product
–
from anthropogenic sources or both.
Pollutants are found in most parts of the troposphere; nevertheless, surface pollution in the
boundary layer is the most alarming since the concentrations caused by surface sources are
relatively high [6]. An increase in population, a reduction in natural resources, and an
increase in pollutants enhances climate change. It was previously believed that the climate
does not affect the surface of the Earth or living organisms in the Earth's crust. It plays an
important role in determining climate change on Earth [7]. Global warming associated with
climate change is one of the most discussed topics. There are also natural causes and the
various anthropogenic effects of air pollution worldwide. Many factors play a decisive role
in climate change and global warming, leading to changes in global temperatures and the
nature of precipitation [8]. Anthropogenic pollution occurs mainly due to pollutants
entering the air from industrial enterprises, automobiles, air, rail, and water transport, and
the use of various types of fuel. In the
era of science and technology, air pollution is
becoming more intense [9]. Currently, there are more than 40,000 sources of air pollution in
Uzbekistan, and almost half of them are not equipped with filters, which leads to more than
2 million pollutants in the country with more than 150 pollutants per year, tons of waste are
released into the atmosphere [10]. As a result of the effect of polluted air on the
environment, many health problems arise both for the environment and for humans and
cause diseases such as asthma, bronchitis,
cardiovascular diseases, heart attack, and
hypertension [11]. The largest industrial cities of the country are Tashkent, Andijan,
Fergana, Navoi, and others, which are among the largest cities in Europe in terms of air
pollution [12]. Atmospheric air is mainly contaminated with carbon monoxide,
nitrogen
oxides, and sulfur oxides. From a scientific point of view, the choice of decorative trees and
their durability is important for cleaning and protecting the air from pollution. In this
situation, it is necessary to conduct phenological observations of growing trees under these
conditions and study the quantity and quality of substances in their various organs. It is also
known that most of the toxins are primarily affected by the leaves of the trees due to
photosynthesis and many processes that occur in them. From this, we can conclude that the
amount of photosynthetic pigments in trees is a measure of resistance to harmful gases in
trees. Given the above, we plan to study the formation of green and yellow dyes on the
leaves in the example of the city of Tashkent. Purpose of the study. Study of drought
tolerance of decorative trees, determination of atmospheric air pollution, seasonal studies of
dyes in tree leaves along the main highways of the city of Tashkent.