nCa Report
About half of the research paper of Pavlenko was reproduced in the previous part of this series. Now we are presenting the remaining part of his paper.
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There are few localised species, namely endemic and sub-endemic representatives. Among the endemics are the Karakum species: Artemisia dimoana, Crucianella sabulosa and a recently described species, one of the type specimens of which was collected in the territory of this NNP is Ferula karakumica (Pavlenko, 2019). Of the sub-endemics found in the Karakum and neighbouring Kyzylkum, the following occurs in the Bereketli Garagum area: Chartoloma platycarpum, Prangos ammophila and Cousinia annua.
We want to mention some interesting species confined to the Khorasan-Kopetdagh mountain system but found in the PA area. These are Allium regelii, Caccinia macranthera and Leontice ewersmannii. The northern boundaries of their main habitat, the KopetdagKhorasan mountains, are 250 km from the reserve’s areas. Along the meridian of the reserve, a narrow strip of sparse populations of these species are located, and the Bereketli-Garagum section of the reserve is the northernmost limit of their distribution.
Consequently, the reserve’s flora, being a typical desert flora, is not only influenced by neighbouring desert habitats but is also supplemented by typical mountain species and will probably continue to be supplemented in the future.
It should be noted that some formations belonging exclusively to the desert type of vegetation on grey-brown, takyr-like and solonchak soils and sandy substrates of varying degrees of consolidation are present within the reserve. Most areas are occupied by Haloxylon persicum formations, occupying almost all sandy areas. Notable are Haloxylon ammodendron communities dominating along the sides of solonchak depressions. The grey-brown soils are dominated by the boyalych and camel-grass (Xylosalsola arbuscula and Artemisia kemrudica) communities. In areas where saxaul was heavily harvested for fuel before establishing the reserve, shrub communities of Xylosalsola richteri and Ephedra strobilacea dominate. Ephemera-adrasana association (Ephemerae – Peganum harmala) dominates in the near-solonchak areas, knocked out by cattle. On the bottoms of solonchak depressions, there are synusions of Halocnemum strobilaceum, often with low-growing and depressed Reaumuria oxiana. On highly saline areas, there is no vegetation at all. The saxaul community Arthrophytum lehmannianum, located along Unguz in areas with minimal salinity, is remarkable. Apart from Unguz, there are no other communities dominated by this species in Turkmenistan.
In order to describe the vegetation and determine its distribution pattern, an ecological profile was created from the bottom of the Unguz Depression along the side of the depression to the Murze-Chirla cordon across the sand massif. This cordon is located in the easternmost part of the reserve. The work was conducted in April 2019. The length of the profile is 2100 m.
The Black Saxaul Formation was observed directly at the bottom of the depression, with specimens of the edificator being stunted, not exceeding 1 -1.2 m in height and with crowns no more than 1 m wide. This is explained by increased soil salinity and, consequently, the floristic composition here is extremely small – only 16 species. We note several associations in the formation: boyalych-black saxaul (Xylosalsola arbuscula – Haloxylon ammodendron) with Asparagus turkestanicus; Cherkezoan black-saxaul (Xylosalsola richteri + Haloxylon ammodendron) with Zygophyllum eichwaldii along the middle of the depressive ridge; motley grass black-saxaul (Ephemerae – Haloxylon aphyllum) in the upper part of the ridge. As one moves upwards from the bottom of the depression, soil salinity decreased markedly, the amount of stony inclusions and clay in the soil decreased, and the substrata became sandier.
A narrower strip was the boyalych formation with several associations in which it was difficult to identify the edificator, but the number of plants per hectare and productivity of boyalych exceeded other species. Soils are sandy loamy, with minimal clay and stony inclusions. The floristic composition contains 33 species. In this formation, we note the following associations: Saxaul- Saxaul- Saxaul-Boyalych (Arthrophytum lehmannianum – Xylosalsola arbuscula) with the participation of Reaumuria oxiana; saxaul-cherkez-boyalych (Arthrophytum lehmannianum – Xylosalsola richteri – Xylosalsola arbuscula) on compacted soils; kemrud-sagebrush-saxaul-arbuscula (Artemisia kemrudica + Arthrophytum lehmannianum – Xylosalsola arbuscula). In addition to the above phytocenoses, several other combinations of sub-edificators are present in this formation, but their ranges are relatively small and have not been considered.
The next formation, represented by 36 species, is the Cemerodonta, located on horizontal plots above the slopes of the hollow. The soils are slightly compacted. The main campanulate association is boyalych kemrud (Xylosalsola arbuscula – Artemisia kemrudica), with perennial and annual grasses in the lower tier.
The white saxaul formation is the main phytocoenosis of the reserve, occupying at least 80 percent of its area. It was also represented on the profile by a very wide strip of at least 1.2 km. The formation is represented by 138 species, with about 100 species found only in white-saxauls. The phytocoenosis is located on sandy substrates. The condition of all members of the formation was in satisfactory condition. We note the following associations in this phytocenosis: Kadym-Singren white-saxaul grass (Calligonum setosum – Astragalus squarrosus – Haloxylon persicum) with herbs and cereals in the lower tier; cherkez-kemrudsagebrush white-saxaul grass (Xylosalsola richteri – Artemisia kemrudica – Haloxylon persicum) with herbs and mixed cereals; kandym-suzen white saxaul (Calligonum setosum – Ammodendron conollyi + Haloxylon persicum) with the active participation of Convolvulus eremophilus and herbaceous grasses; cherkez white saxaul (Xylosalsola richteri + Haloxylon persicum) with Calligonum setosum, Ammodendron conollyi, Ephedra strobilacea, Artemisia eriocarpa and Poaceae in the lower tier.
The last link in the profile was the herb-harmel peganum association (Ephemerae + Peganum harmala) in an area of increased anthropogenic pressure. It should be noted that this is in the vicinity of the active Yoloten well, and before the reserve was established, cattle used to drink here, especially in the summer. The area is sandy takyr in places, almost completely devoid of usual vegetation. The association includes a number of introduced plants: Suaeda arcuata, Tribulus terrestris, Carthamus oxyacanthus and others. The characteristic flora is represented by single specimens of the genus Eremopyrum and Carex physodes, Astragalus flexus, A.squarrosus and Smirnowia turkestana. The latter three species must have appeared here after the cessation of grazing. Along the edge of the site, Convolvulus divaricatus is notable.
Thus, this profile characterises the majority of sections of the Prigunguz, i.e. areas immediately adjacent to the Unguz chain of depressions. In the remaining areas, namely those to the north and south of the Unguz, the White Saxaul Formation prevails with a complex of associations in which Calligonum, Xylosalsola richteri, X.arbuscula and, less frequently, Ephedra strobilacea, Ammodendron conollyi are the most common subedificators. In areas where intensive grazing and collection of saxaul for fuel was undertaken, the dominant role of the latter is significantly reduced.
Conclusions
The following conclusions can be derived from the above:
- According to the geobotanical zoning, the territory of Bereketli-Garagum State Reserve is located in the South Turan province and is located at the junction of Low and Zaunguz Karakums, including a chain of solonchak depressions. This location affects the composition of flora and vegetation of the protected area.
- During three short expedition surveys, 181 species of higher vascular plants from 33 families were recorded in the protected area, of which eight families belong to Liliopsida, 24 to Magnoliopsida and one to Chlamydospermae. All species belong to 105 genera.
- As in all desert areas of Central Asia, the dominant family is Amaranthaceae, with 27 species. In addition, the dominant genus is Astragalus (Fabaceae), with 14 species.
- A 47 desert plant life forms were recorded, dominated by early spring annuals with 35 species.
- Geographical elements are represented by 9 habitat types. The most representative are the Turanian areal and its associated elements. There are 137 such species, representing 75.7 percent of the floristic composition.
- The main vegetation formation that occupies at least 80 percent of the reserve area is the white saxaul forest, with many associations and combinations of sub-edificators.
- The areas which were under increased anthropogenic load before the establishment of the reserve have seen a gradual restoration of vegetation. In particular, the perennial herbaceous flora and the presence of young and immature specimens of tree and shrub vegetation are restored everywhere in such areas.
Acknowledgements
The comprehensive research of the Bereketli Garagum State Reserve was initiated and funded by the CADI (Central Asia Desert Initiative) project, which is jointly implemented by Greifswald University, the Michael Succow Foundation (Germany) and the Food and Agriculture Organization of the United Nations (FAO). The project is part of the International Climate Initiative (IKI). The initiative is supported by the Federal Ministry of the Environment, Nature Conservation and Nuclear Safety (BMU) based on a decision by the German Bundestag. In addition to Turkmenistan, teams from Kazakhstan, Uzbekistan, Mongolia, and China participate in the projects. The author would like to thank the staff of the M. Succow Foundation for their comprehensive assistance and close cooperation. /// nCa, 16 May 2024 [to be continued] (photo credit – J. Wunderlich)