On the issue of expanding the boundaries of the Natural Monument “Steppes near the Melovoe village” (Saratov Region, Russia)

Conservation of plants species is an integral part of conserving biodiversity in general. Establishing the natural monuments is an efficient method of conserving plant diversity. The aim of this study is to substantiate the need of expanding the boundaries of the natural monument “Steppes near the Melovoe village” in the Saratov Region, Russia. Standard methods of studying plant communities and coenopopulations were applied. The study of the plant communities needing protection was based on the criteria adopted by the Saratov Region Green Data Book. The description of unique communities and plant species needing in territorial protection is given. Currently, two plant communities unique for the region and several significant reference steppe communities bearing large populations of protected plant species (Iris pumila, Convolvulus lineatus, Stipa pennata, Adonis volgensis, Hedysarum grandiflorum) are still beyond the boundaries of this natural monument.


Introduction
Conservation of plants species is an integral part of conserving biodiversity in general. An efficient method of conserving phytodiversity is establishment of natural monuments. Nowadays, there are more than 90 protected areas in the Saratov Region, most of them are natural monuments [1]. The Natural Monument "Steppes near the Melovoe village" is located in the southeast of the Saratov region to the border with the Republic of Kazakhstan (figure 1).
Steppe areas near the Melovoe village occupy the western slopes of the Obshchii Syrt uplands [2]. Large populations of optional and obligate calciphytes, including the species protected at the regional and federal levels [3,4] -Anthemis trotzkiana, Artemisia salsoloides, Linaria cretacea, Matthiola fragrans, Anabasis cretacea, Gypsophila volgensis -are the components of steppe vegetation on carbonate soils (figure 2). This natural monument is of utmost importance for the preservation of landscape and biodiversity.
The aim of this study is to substantiate the need of expanding the boundaries of the Natural Monument "Steppes near the Melovoe village" in the Saratov Region.

Materials and Methods
Standard methods of studying plant communities and coenopopulations were applied [5][6][7]. The study of the plant communities needing protection was based on the criteria adopted by Green Data Book  [8,9]. The dominant-determinant principle was followed, being implemented in naming the plant communities. Latin names of plant species are given according to S. Cherepanov's summary [10]. The protected plants' categories and status are cited by the Saratov Region Red Data Book 2nd Edition: 2 (V) -vulnerable species, will be endangered soon, 3 (R) -rare species [2]. The study was carried out as part of inventory research for the need of protection of the steppe communities in the Saratov region [11].

Results and Discussion
We propose to expand the boundaries of the Natural Monument "Steppes near the village Melovoe" and to include a section of chalk outcrops near the Melovaya River between the northwestern border of the monument and the village Melovoe into the zone under protection (figure 3). Two unique phytocoenoses with the dominance of Camphorosma lessingii and Limonium suffruticosum are noted for this area. Until 2014, the territory of the Saratov Region lacked the data on plants communities with the dominance of this species and its coenotic role on the chalk soils. Camphorosma lessingii is the codominant in this community, it is a species that was totally absent in the lists of regional flora for recent years. It was recommended to include Camphorosma lessingii into the third edition of the Saratov Region Red Book [12]. Two protected species Matthiola fragrans (2 (V)) and Crambe litwinowii (3 (R)) were noted in the community in addition to the dominants listed above. Direct destruction as a result of grazing and the slope wash are the main destabilizing factors for these communities. These are natural regionally rare phytocoenoses with protected edificator plant species, so this is the major conservation motive.
The conservation within the boundaries of natural monuments of different rank, control of the state of communities, restriction of certain types of economic activity are the main recommended protection measures for such communities.
That is why it is necessary to expand the boundaries of the Natural Monument "Steppes near the Melovoe village" and to include the chalk outcrops with these unique phytocoenoses into the list of the regional protected areas. Currently, two plant communities unique for the region and several significant reference steppe communities bearing large populations of protected plant species (Iris pumila, Convolvulus lineatus, Stipa pennata, Adonis volgensis, Hedysarum grandiflorum) are still beyond the boundaries of this natural monument.
When expanding the boundaries, the Nature Monument "Steppes near the Melovoe village" will provide territorial protection to many reference steppe phytocoenoses, to the communities of the protected steppe and calcicolous plant species, to exceptionally rare plant communities known by 3-5 location within the region, and to the two unique communities, which are known only from the surrounding area of the Melovoe village, the Ozinsky District of the Saratov Region. The conservation potential of this natural monument should be recognized as one of the highest among all the natural monuments of the Saratov Region [2,13,14]. The future expanding of the boundaries of this natural monument located far from the regional center, in the southeastern part of the region, allows us to hope for a possibility of conserving its biodiversity in full.