Adaptive Adjustment in Taraxacum Officinale Wigg . in the Conditions of Overburden Dump

Morphological and anatomical features of the leaves and roots of Taraxacum officinale Wigg., growing under the conditions of the rocky dump of the Kedrovsky coal mine of the Kemerovo region, were studied. It was revealed that the specific environmental conditions of the dump cause morphological and anatomical changes in the leaves and roots of the dandelion. At the level of morphology, a decrease in the average leaf area, a thickening of leaf blades, a tendency to decrease the number of leaves in the rosette, a significant decrease in the mass and length of the roots. At the level of the anatomical structure of the leaves, there is a significant increase in the thickness of the mesophyll, a tendency to decrease the thickness of the tissues of the upper and lower epidermis, a decrease in the number of cells in 1 mm2 and an increase in the size of stomata in the tissues of the lower and upper epidermis, a decrease in the number of stomata by 1 mm2 and a stomatal index on the upper epidermis. At the level of the anatomical structure of the roots, the radius of the root decreases, the radius of the cortex and phloem, the diameter of the xylem.


Introduction
As a result of coal mining, the area of disturbed land in Kuzbass is more than 100 thousand hectares.As a result of the open method of coal mining, the emerging rock dumps are characterized by specific ecological conditions -a lack of productive moisture, failed water permeability, a contrasting temperature regime on different relief elements; low potential fertility of embriozems, therefore they are a classical object for studying the adaptive mechanisms of plants planted on them.A high degree of resistance of some species of higher plants is provided by a combination of morphological, physiological, anatomical adaptive reactions, which makes these plants potentially capable of improving the quality of the natural environment -urban areas, industrial zones and technogenically disturbed lands.Adaptations of plants are associated, first of all, with the rearrangements of their assimilating organs, which, in connection with their gas exchange function, are highly sensitive to external influences [1].It is known that morphological and anatomical rearrangements change the physiological status of plants in extreme conditions of existence for more efficient use of environmental resources [2].The aim of the work is to study adaptive rearrangements at the morphological and anatomical level in Taraxacum officinale Wigg., which grows in conditions of the rocky dump of the Kedrovsky coal mine.

Materials and Methods
Studies were carried out on the rock dump "Southern" of the Kedrovsky coal mine.The dump has a flat-inclined relief with a height of 58 m, an area of 599.3 hectares.Dump rocks are represented by sandstone (60%), siltstones (20%), mudstones (15%), loams and clays (5%).The experimental site is located at the top of the dump (the location coordinates of the site are 55°30'39'' NL. 86°04'00" EL.).The life of the biocenosis lasts 7-10 years.The technical and biological stages of recultivation (landings of Pinus sylvestris L. and Onobrychis arenaria (Kit.)), the initial stages of the formation of meadow communities are observed; and there are separate sections of stony scatterings of up to 3 m 2 in size from various rock formations completely devoid of vegetation.Projective coverage is up to 50%, on rocky areas -below 10%.There is no turfness.In the herbage prevail Onobrychis arenaria, Taraxacum officinale Wigg, Melilotus officinalis (L.) Pall., Artemisia sericea Web.Ex Stechm., Picris hieracioides L. Еmbriozems are characterized by an alkaline reaction (pH of water extract 7.1-7.7),medium availability of humus (3.5%), low availability of mobile forms of phosphorus (10-50 mg / kg) and nitrogen (3.6-6.0 mg / kg), high potassium (100-140 mg / kg), a lack of productive moisture (19-22 mm in the 0 ... 20 cm layer).
The control plot was located 15 km north-west of the dumps at the border of the birch forest.A large area (about 80%) of the site is occupied by gramineous herb meadow.Projective coverage is 95-100%, the soil is not turfed.The meadow communities are dominated by Centaurea scabiosa L., Hieracium umbellatum L., Lathyrus pratensis L., Achillea Asiatica Serg., Taraxacum officinale Web.
The object of research was common dandelion (Taraxacum officinale Wigg.), as the most widespread type of perennial herbaceous plants growing on dumps.Preparation of raw materials was carried out in dry sunny weather, according to generally accepted rules during the maximum development of the vegetative mass (end of May 2016).Collected raw materials with no visible signs of damage from 15 sites with a size of 1 m 2 from the experimental and control sites.For morphological studies, the sample of plants from each registration site was 10 plants, total from the experimental and control sites -150 plants.The area of the leaves (S) was determined by scanning them and then processing the image using the computer program Image Tools.For anatomic research, plant material was fixed in a 60% solution of ethyl alcohol.From the middle part of the leaf blade and root, transverse sections were made by a microtome and placed into glycerol.Measurements of the anatomical parameters of the leaves (the thickness of the leaf and its tissues, the number of cells in 1 mm 2 of the lower and upper epidermis, stomata sizes) and roots (root radius, cortex, phloem, diameter of the xylem) were carried out with the Axioscope-2 + microscope, model ZEISSN HBO103 and N XBO75 (Germany) with eyepiece micrometer, camera and software.Calculation of the stomatal index (SI) was carried out according to the formula: SI = N st *100% / (N st + N ke ), Where N st is the number of stomata per 1 mm 2 , and N ke is the number of the major epidermal cells of the leaf per 1 mm 2 .Mathematical processing and interpretation of the experimental results were carried out using the Statistika 8.0 application software package, descriptive statistics.

Results and Discussion
A comparative analysis of the morphological parameters of a dandelion growing in various ecological conditions has shown that in the waste dumps in plants with a high degree of reliability, the green leaf mass decreases from one plant (by 20%), the average leaf area (by 39%), the mass and length of the root (by 46 and 35%, respectively), there is a tendency to     In particular, in the common dandelion plants growing on dumps, there is a tendency to decrease the number of cells in 1 mm 2 and to increase the size of stomata in the tissues of the lower and upper epidermis, the number of stomata is significantly reduced by 1 mm 2 (by 12 and 26%, respectively); on the upper epidermis there is a significant decrease in the stomatal index (by 14%).Given the low supply of productive embriozems in the waste heaps, a decrease in the stomatal index is a natural reaction of plants aimed at survival.
There is information in the literature that the low frequency of stomata in combination with their large size contributes to a more effective control of water exchange [5,6].The data obtained by us also agree with the results of the studies of I. I. Krokhmal [7] who established that in C. sibirica at the level of rosette leaves adaptation to the harsh conditions of growth is achieved by reducing the number of stomata and increasing their size.
The use of correlation analysis showed that the common dandelion growing in conditions of the rock dump increases the number of reliable correlations between the anatomical parameters of the root and the provision of soil with microelements and productive moisture.In particular, in the dandelion, close positive correlations radius of root, radius of cortex and diameter of xylem with phosphorus, nitrogen and productive moisture of embriozems appear in dandelion; the radius of phloem is positively correlated with the nitrogen content and the productive moisture in the soil (Table.4).It should be noted that an increase in the total number of correlation links occurs due to the formation of positive correlations, which, as is known, control the development of biosystems and arise in critical periods for the body.The coordinated increase in the number of correlation links between the anatomical characteristics of the common dandelion root and

Conclusion
Specific ecological conditions of the rock dump (low availability of mobile forms of phosphorus and nitrogen, lack of productive moisture) of the Kedrovsky coal mine cause morphological and anatomical changes in the leaves and roots of Taraxacum officinale Wigg.It has been established that adaptive reactions permitting the survival of Taraxacum officinale Wigg. in conditions of a rock dump are: -at the level of plant morphology -decrease in leaf mass from one plant, average leaf area, weight and root length, formation of a tendency to decrease the number of leaves in the rosette; -at the level of the anatomical structure -a significant increase in the thickness of the mesophyll, a tendency to decrease the thickness of the tissues of the upper and lower epidermis, a decrease in the number of cells in 1 mm 2 and an increase in the size of stomata in the tissues of the lower and upper epidermis, a decrease in the number of stomata by 1 mm 2 , epidermis, a decrease in the radius of the root, the radius of the cortex and phloem, the diameter of the xylem.Identified morphological and anatomical changes in Taraxacum officinale Wigg.are a manifestation of xerophytization -an adaptive reaction at the level of the whole plant, aimed at survival in adverse conditions of the heap.
In the conditions of the rock dump, an increase in the number of positive reliable correlations between the anatomical parameters of the root Taraxacum officinale Wigg.and the provision of embryozems with microelements and productive moisture has been established.Positive correlations, as we know, control the development of biosystems and arise in critical periods for the body.The coordinated increase in the number of correlation links between the anatomical characteristics of the dandelion root and agrochemical indicators of embryosemes can be considered as a specific reaction aimed at survival and stable existence in conditions of the rock dump.

Table 2 .
A

Table 4 .
Correlation links between anatomical characteristics root Taraxacum officinale Wigg.and agrochemical indicators embryozems

Dependence of the studied features Reliable correlations
The Second International Innovative Mining Symposium agrochemical indices of embryosemes can be considered as a specific reaction aimed at survival and stable existence in conditions of the rock dump.