Assessment of Plant Biodiversity and the Floristic Composition in the Black Irtysh River Valley (Kazakhstan)

Abstract

The Black Irtysh River, a major tributary of the Ob River, traverses diverse ecological zones, influencing the distribution and composition of its floodplain vegetation. This study focused on the Black Irtysh River valley, a key segment of the Irtysh basin, to assess the current state of its plant communities. To compile expedition routes and a preliminary floristic list, a critical revision of more than 1000 herbarium sheets was carried out in the herbarium collections of Kazakhstan (Altai Botanical Garden and Institute of Botany and Phytointroduction). During the field season, a study of plant biodiversity was carried out along the entire coastline of the Black Irtysh. As a result, 217 species of higher vascular plants were identified (55% of those previously found in herbarium archives) from 139 genera and 43 families. The habitats of two Red Book species were discovered: Tulipa patens and Tulipa uniflora. It was found that the flora of the Black Irtysh is similar to the flora of the entire Zaisan depression, and families Poaceae, Asteraceae, Amaranthaceae, Caryophyllaceae, Rosaceae, and Fabaceae are predominant. Geobotanical surveys revealed that the species composition of plant communities is poor and similar among survey points. Only the western part of the river delta is characterized by high rates of projective cover and reserves of forage plants. The main factors of anthropogenic influence are fires, livestock grazing, and deforestation.

1. Introduction

Rivers valley flora, which develop along rivers or streams, typically grow in lowland river valleys within the range of periodic floods. They play a significant role in nitrogen storage and distribution [1], serve as carbon sinks, aid in water conservation [2], and help mitigate global climate change [3]. Additionally, they are vital for maintaining biodiversity [4], ensuring the integrity of ecosystems [5], securing water and agricultural resources, and supporting local agricultural and livestock production [6].

The Irtysh River, the largest tributary of the Ob River, traverses diverse botanical and geographical areas, each characterized by distinct vegetation patterns. The floodplain of the Irtysh River spans approximately 595 thousand hectares and is of significant transboundary importance as its flow is regulated by China, Kazakhstan, and Russia. Within Kazakhstan, the Irtysh hydrographic basin is situated in the eastern part of the Republic, encompassing the East Kazakhstan, Abay, and Pavlodar regions. The river begins on the slopes of the Altai Mountains of Mongolia at an altitude of 2500 m in the western part of the Chinese province of Xinjiang. Before it flows into Lake Zaisan, it is called the Black Irtysh; the water management section of the river in its Kazakhstani segment has a length of 110 km and is a flat area with a swampy delta.

The Irtysh River’s extensive floodplain hosts a variety of ecosystems and plant communities that reflect the botanical–geographical zones it traverses. In the upper reaches, the river flows through the mountainous regions of East Kazakhstan, where alpine and subalpine vegetation dominate [7,8]. As the Irtysh River descends into the lower altitudes, the vegetation transitions into forest–steppe and steppe zones, typical of the Pavlodar region. Here, the floodplain is dominated by a mix of deciduous forests (dominated by plant species belonging to the Salicaceae and Betulaceae families [9]) and grasslands and various grasses and herbs adapted to the more temperate conditions [10]. These regions are vital for biodiversity conservation, providing habitats for numerous plant and animal species [11]. Moreover, the Irtysh River floodplain plays a crucial role in the hydrological and ecological dynamics of the region. The river’s regulation by the neighboring countries has significant implications for water management and ecological sustainability. For instance, the construction of reservoirs and hydroelectric power stations along the river affects the natural flow regimes, sediment transport, and nutrient cycling, which in turn influence the structure and function of floodplain ecosystems [12].

The study of floristic territories in Kazakhstan is of high relevance [13]. During the last decade, several studies on floristic novelties and local rare species were performed. Those include the identification of a new plant species from southeast Kazakhstan named Allium toksanbaicum [14]; a review of Orchidaceae Juss. in the northern part of Kazakhstan [15]; studies on the species composition of the orchid genus Dactylorhiza Necker ex Nevski [16] and the genus Kalidium Moq. in the flora of Kazakhstan [17]; a study on the morphological and genetic characteristics of two similar species of the genus Prunus L. in eastern Kazakhstan [18]; and a botanical description of the current state of populations of the threatened species Dactylorhiza incarnata (L.) Soo in Kazakhstan Altai [19]. Stocks of economically valuable plant species were assessed in Kazakhstan [20,21,22,23] in order to maintain genetic diversity within wild plant populations and ensure the adaptability and resilience of ecosystems.

The landscape uniqueness and great practical significance of the vegetation cover of the Irtysh floodplain make it an interesting and important object of research. Floristic and geobotanical studies of different parts of the Irtysh basin continue to be studied at the present time [24,25,26,27,28,29,30]. Previously, rare plant species, such as Allium caespitosum Siev. ex Bong et Mey, Allium galanthum Kar. et Kir., Allium mongolicum Regel., Alyssum fedtschencoanum N. Busch., Dactylorhiza salina (Turcz. Ex Lindl.) Soo, Eremurus inderriesis (Bieb.) Regel., Populus pilosa Rehder., Rheum compactum L., Rubia resniczenkoana Litv., Salix caspica Pall., Salix fragalis L., Thelipteris palustris Schott., Trapa rossica V. Vassil., Trapa saissanica (Fler) V. Vassil., Tulipa altaica Pall., and Veronica arenosa Lind. were found and described in this territory [31]. However, the flora of the Black Irtysh valley, despite its high biodiversity, has been poorly studied [32].

Due to this, a comprehensive survey was conducted on the distribution of wild valley flora around the Black Irtysh. The purpose of this study is to assess the current state of plant communities in the valley of the Black Irtysh River, compile an actual floristic list of higher plants of the Black Irtysh, and determine the degree of anthropogenic influence on the biodiversity of this territory.

2. Materials and Methods

2.1. Study Area and Expedition Routes

To compile a preliminary list of species previously recorded in this territory, as well as to develop expedition routes, a critical review of the herbarium collections stored in the main repositories was carried out using 750 herbarium sheets from the Altai Botanical Garden (ABG, Ridder city, East Kazakhstan region) and 250 herbarium sheets from the Institute of Botany and Phytointroduction (AA, Almaty city, Almaty region).

Given the complexity of the terrain and the vast area of the Zaisan Basin, route reconnaissance methods were employed for the collection of factual material in the field [33]. To obtain a comprehensive understanding of the natural flora components in the study areas, a series of routes were established. The total length of these routes along both banks of the Black Irtysh River, spanning from the border with China to its confluence with the Bukhtarma Reservoir, measured 110 km.

Three expedition trips were carried out from April to September to review all stages of vegetation changes. The routes ran along both banks along the floodplain of the Black Irtysh, extending from the border outpost with China to the confluence with Lake Zaisan to cover the maximum floristic composition.

2.2. Field Investigations

To assess the current state of the vegetation cover in the Black Irtysh River valley, geobotanical profiles were selected. Three profiles were laid out across the valley of the Black Irtysh River (Figure 1).

According to archival materials and herbarium collections, these profiles are characterized by a maximum floristic diversity of plant communities; this provides informational content and a high level of reliability in floristic and geobotanical studies of the vegetation cover of the floodplain of the Black Irtysh River. To determine the main dominants in plant communities, 31 geobotanical descriptions were made at 31 sites (Table 1).

2.3. Study Parameters and Statistics

To assess the current state of the flora species at the population–organism level and green mass, transects of various modifications were laid depending on the area occupied by a particular population. The following community parameters were determined: height of vegetation cover, projective cover, and yield of green mass of forage plants.

Genera and species names were taken from Plants of the World Online [34]. The conservation status of rare species was given according to the Red Book of Kazakhstan (2014) [35] and according to IUCN (2024) [36]. The families were arranged according to the APG4 evolutionary system [37]. Species and genera in families were arranged alphabetically. Correlation analysis, canonical correspondence analysis, and a cluster dendrogram were constructed using the R ver. 4.1.3 software [38]. Cluster analysis was performed using the neighbor-joining (NJ) clustering method in PAST ver. 4 [39].

3. Results

3.1. Analysis of Herbarium Collections

Analysis of archival and herbarium collections showed a high degree of botanical diversity. The actual habitats of 395 taxa were established. According to preliminary data from herbarium collections, the floristic composition of the Black Irtysh River valley was dominated by xerophytic and xeromesophytic species from 57 families (Table 2). The dominant families were: Amaranthaceae—58 species (15%), Asteraceae—43 species (11%), Poaceae—42 species (11%), Fabaceae—38 species (10%), and Polygonaceae—26 species (7%).

3.2. Field Assessment of the Flora of the Black Irtysh

During the 2023 field season, as a result of expeditions to survey the flora of the Black Irtysh River valley within its Kazakhstani section, 217 species from 139 genera and 43 families of higher vascular plants were identified (Table S1). The actual expeditionary survey did not reveal the majority of the taxa listed in archival and herbarium collections (Table 2). As a result, 55% of previous records (395 species) were actually identified in the Black Irtysh River valley. The dominant families were different between the herbarium records and the results of the field expedition as well. The dominating families included Poaceae, Asteraceae, Amaranthaceae, Caryophyllaceae, Rosaceae, and Fabaceae.

The study of the floristic composition from the beginning of the vegetation cover allowed for the identification of rare and endangered species of early spring flora: Gagea fedschenkoana Pasche, Tulipa altaica Pall. ex Spreng, T. patens C.Agardh ex Schult. Schult, and T. uniflora (L.) Besser Backer. (Table 3, Figure 2). Two of these species (Tulipa patens and Tulipa uniflora) are listed in the Red Book as having category 3 status: rare, declining in number, and species with a shrinking range. These species were found in a limited area and were under strong anthropogenic influence.

The predominance of xeromesophytic species in herbarium archives has changed towards xerophytic species according to expeditionary results (Table 4). The proportion of hygrophytic species decreased from 4 to 2% (representatives of the Nuphaeaeceae family). The number of genera in the floristic composition decreased from 151 to 139 genera.

In terms of the number of species, the genus Artemisia also remains dominant with 7 species (previously 14) (Table 4). The share of Allium decreased from 13 to 3 species, and Astragalus from 12 to 2. The share of petrophytic genera such as Silene and Dianthus increased noticeably from 1 to 6 and from 0 to 2, respectively.

Analysis of life forms showed a significant increase in shrubs and subshrubs—13 (6%) and woody plants—15 (7%) in relation to herbaceous plants—189 species (87%).

In terms of economic value, the dominant species were as follows: forage plants—29 species (13%), medicinal—30 species (14%), food—3 species (3%), honey plants—18 species (8%), poisonous—3 species (1%), ornamental—7 species (3%), technical—3 species (1%), rare—4 species (2%), and relic—3 species (1%).

3.3. Geobotanical Studies of Plant Communities

The floristic composition on the profiles varied from 53 to 56 species of higher plants (Table S1). In terms of species composition, plant communities of three profiles were relatively poor and similar to each other with similar predominating species (Figure 3).

Profile I was dominated by Leymus gigantea, Halimodendron halodendron, Annobasis salsa, Calamagrostis epiogejos, Salix viminalis, and Glycyrrhiza uralensis. Profile II was dominated by Artemisia scoparia, Elytrigia repens, Glycyrrhiza uralensis, Halimodendron halodendron, and Pragmites australis. Profile III was dominated by Pragmites australis, Elytrigia repens, Halimodendron halodendron, Glycerhiza glabra, and Ephedra intermedia.

Geobotanical description of the profiles is given in Table S2. As a result of a survey of 31 points, it was found that only 7 points had a projective coverage above 80%: II-27, III-3, III-4, III-5, III-7, III-8, and III-18. Eleven points had projective coverage less than 20%: I-11, I-12, I-21, I-25, I-26, II-30, II-31, III-6, III-13, III-15, and III-17 (Figure 4A). The highest projective coverage was found in profile III, while the projective coverage in profile I did not exceed 30%.

An assessment of the yield of green mass at the surveyed points revealed high operational reserves of forage plants in 3 profiles: III-2, III-3, III-4, III-7, and III-8 (Figure 4B). Large reserves of cereals and legumes were concentrated here. The green mass in profiles I and II had no economic significance and their yield did not exceed 20 × 100 kg/ha (Figure 4B). The surveyed plant communities were mostly two-tiered, and less often one- or three-tiered. The third tier from 200 to 700 cm was represented by Populus nigra, P. tremula, and Salix viminalis. The second tier was 150–200 cm high, and was represented by Halimodendron halodendron, Rosa laxa, and Phragmites australis. The first tier was 50–100 cm high, and was represented by representatives of the families Fabaceae and Poaceae (Figure 4C).

The study of the correlation coefficients between the environmental conditions and the vegetation cover of the study area showed a weak positive correlation between the type of soil and growing conditions (Figure 5). There was also a slight negative correlation between the projective cover of vegetation and the altitude above sea level, which was associated with more humid conditions at the mouth of the river.

Canonical correspondence analysis showed a high similarity between points III-1, I-25, and II-26 in relation to altitude above sea level, as well as a high similarity between III-2, III-3, III-5 and III-4 in terms of soil cover (Figure 6).

A study of a cluster analysis of the floristic profile points revealed significant isolation of points from the third profile, which is explained by a richer floristic composition and high yield resource (Figure 7). There was a significant similarity between the points from the first and second profiles, which were similar to each other in terms of dominant species.

3.4. Anthropogenic Impact and Degree of Disturbance of Plant Communities

Analysis of the floristic diversity of the Black Irtysh showed intense degradation of the floristic composition. This was confirmed by the high number of species in the 10 leading families: 140 species out of 217 (64.1%) (Table 5). This was significantly higher than in the Zaisan depression—61% and the Kazakhstan Altai—57.6%.

A significant influence of weed species was noted: Chelidonium majus, Atriplex hastata, Rumex confertus, Humulus lupunus, Cannabis ruderalis, Cannabis sativa, Urtica cannabina, Urtica dioica, Cuscuta europaea, and Orobanche amoena. An analysis of disturbance to phytocenoses showed a stable negative anthropogenic influence. The main factors were uncontrolled grazing of livestock, numerous fires, burnt areas and felled trees, excessive grazing of cattle, and illegal logging (Figure 8, Table 6).

4. Discussion

Studying the floristic composition of territories, assessing the state of plant communities, and establishing limiting factors and the degree of disturbance to communities are an important part of preserving the biodiversity of the plant world.

The study showed that the flora of the Black Irtysh has a clearly expressed steppe and semi-desert type of vegetation. The territory of the Black Irtysh, in comparison with other floristic territories of eastern Kazakhstan, is inferior in species diversity to large mountain ranges [40,41,42], but surpasses the flora of small mountain ranges [43]. Our work describes the floristic composition of the Black Irtysh River, which amounts to 217 species. Thus, our study harmoniously complements the research on the biodiversity of higher plants in eastern Kazakhstan.

The flora of the Black Irtysh Valley, which is geographically part of the Zaisan Basin flora [31], is notably enriched with species from families such as Caryophyllaceae and Ranunculaceae, indicating a significant presence of petrophytic and riparian species. However, the proportion of families like Amaranthaceae and Poaceae is considerably lower, reflecting a mesophytic vegetation type. Compared to the flora of the whole Kazakhstan Altai region [44], the flora of the Black Irtysh shares similarities in the leading families, with the exception of the Caryophyllaceae and Polygonaceae families. This difference is likely due to the predominance of low-mountain habitats that are suitable for the xerophytic species within these families. The actual floristic diversity in the Black Irtysh River valley demonstrated a marked decrease in steppe sandy species and a significant increase in petrophytic mountain species. This trend was anticipated to continue, indicating an ongoing intensive soil-forming process in the valley. Additionally, an increase in the proportion of trees and shrubs indicated a forest formation process in the coastal areas. The influence of the location between the large mountain ranges of the Kazakhstan Altai and Sauro-Tarbagatai had changed the flora of the Black Irtysh and the flora of the Zaisan depression as a whole.

During the expeditions, the rare species that were identified had significantly reduced habitat and population density. Representatives of early spring flora were discovered, including endemic rare species Gagea fedschenkoana, T. altaica, T. patens, and T. uniflora, which are also endangered in neighboring areas. To preserve these species, additional measures are required to protect the discovered habitats. Unfortunately, Rheum compactum L., which was previously recorded in the area, was not identified during these expeditions. However, populations of another species, Rheum nanum Siev, were discovered.

The economic importance of the flora of the Black Irtysh was quite high, with a predominance of fodder and medicinal plant species. Special attention was paid to the western part of the river valley (profile III), which exhibited high rates of projective coverage. Profile III was characterized by the maximum overflow of the Black Irtysh in an area with consistent humidity and the presence of a shrub layer. In contrast, the projective cover on Profile I did not exceed 30%, attributed to the lack of rich soil cover and high soil salinity. The main operational reserves of forage plants were concentrated primarily in the western part, averaging 30–35 × 100 kg/ha.

Anthropogenic impacts throughout the area were a significant concern. Generally, the degree of disturbance at all surveyed points varied from moderate to severe, leading to changes in floristic composition and a decrease in species diversity. The surveyed territories were negatively affected by their proximity to populated areas such as Zhideli, Kalihan, Shingeldi, and Boran, where cattle breeding was prevalent. The extensive willow-poplar forests along the Black Irtysh River complicated forestry efforts to control logging and forest fires. Additionally, reforestation measures were ineffective due to the poor quality of soils.

5. Conclusions

Analysis of the Black Irtysh River valley’s flora revealed a rich, but significantly degraded plant diversity. The region’s botanical composition, dominated by xerophytic and xeromesophytic species, has been profoundly impacted by anthropogenic activities. Herbarium records and field surveys indicated a shift in plant communities. A notable decrease in hygrophytic species and an increase in petrophytic ones were observed. The dominance of xerophytic species, particularly those adapted to saline conditions, reflects the ongoing soil formation processes in the valley. Economic valuation of the flora highlighted the region’s potential as a forage resource, especially in the western part. However, the high degree of disturbance, including overgrazing, fires, and logging, poses a significant threat to the ecosystem and its biodiversity. Conservation efforts are crucial to protect the remaining plant diversity. Prioritizing habitat restoration, sustainable land management practices, and the establishment of protected areas are essential for preserving the unique flora of the Black Irtysh River valley. However, further research is needed to assess the long-term ecological implications of these changes and to develop effective conservation strategies.

Author Contributions

Conceptualization, A.S. and A.A.; methodology, E.I.; software, A.S.; validation, A.A., E.I. and A.S.; formal analysis, A.S.; investigation, A.A.; resources, A.A.; data curation, A.S.; writing—original draft preparation, A.S.; writing—review and editing, A.S.; visualization, A.A.; supervision, E.I.; project administration, A.A.; funding acquisition, A.S. All authors have read and agreed to the published version of the manuscript.

Institutional Review Board Statement

Not applicable.

Data Availability Statement

The datasets generated and/or analyzed during the current study are available in the manuscript text and/or Supplementary Materials.

Conflicts of Interest

The authors declare no conflicts of interest.

Footnotes

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Figures and Tables

Figure 1. Field trip routes along Black Irtysh River with geobotanical profiles. Blue box denotes region of survey.

Figure 2. Rare species of early spring flora found in Black Irtysh valley: Tulipa patens C.Agardh ex Schult. Schult. (A), Tulipa uniflora (L.) Besser Backer (B), Gagea fedschenkoana Pasche (C), Tulipa altaica Pall.ex Spreng. (D).

Figure 3. Plant communities of Profile I (A), Profile II (B), and Profile III (C).

Figure 4. Community parameters: projective coverage at surveyed points (A), green mass yield (B), and estimated height of vegetation cover (C).

Figure 5. Correlations of the main factors and conditions of the habitat with the vegetation cover of the territory. Prof: profile; Alti: altitude; Soil: type of soil; ProC: projective coverage; MaxG: max grass layering; VegC: vegetation condition; and Yield: expected yield. Cells with significance at p [less than] 0.05 are highlighted. The directions of correlations are denoted in color scale on the right, with red indicating negative and blue indicating positive.

Figure 6. Canonical correspondence analysis of the studied points.

Figure 7. NJ clustering of floristic profile points.

Figure 8. Main types of anthropogenic influence: uncontrolled grazing of livestock (A), numerous fires (B), illegal logging (C).

Table 1

Points of geobotanical surveys in the floodplain of the Black Irtysh River in the East Kazakhstan region.

Point of Survey	Administrative Name	Landscape and Relief	Geographical Coordinates
			Latitude	Longitude	Altitude, m.a.s.l.
I-9	Kurchum district, vicinity of the village of Zhideli	Upland river valley	48.0117300	85.3307146	410
I-10	Kurchum district, vicinity of the village of Zhideli	Slightly hilly area	48.0125171	85.3310933	407
I-11	Kurchum district, vicinity of the village of Zhideli	Flat area	48.0139150	85.3309350	406
I-12	Kurchum district, vicinity of the village of Zhideli	Flat area	48.0190601	85.3297300	408
I-20	Zaisan district, vicinity of the village of Zhideli	River bank with complex terrain, with numerous hills	48.0081769	85.3343172	406
I-21	Zaisan district, vicinity of the village of Zhideli	Plain with slight swampiness	48.00425950	85.3320150	394
I-22	Zaisan district, vicinity of the village of Zhideli	Thickets of willow and poplar in the riverbed of the Irtysh tributary	47.9983556	85.3291494	412
I-23	Zaisan district, vicinity of the village of Zhideli	Edge of the willow forest	47.9952545	85.3266535	404
I-24	Zaisan district, vicinity of the village of Zhideli	Willow forest, cut by longitudinal gullies	47.9885578	85.3251367	403
I-25	Zaisan district, vicinity of the village of Zhideli	Sand dunes	47.9814335	85.3198800	409
II-26	Zaisan district, vicinity of the village of Buran	Banks of the river bed, sand dunes	47.9957685	85.1689352	401
II-27	Zaisan district, vicinity of the village of Buran	Plain, no changes in relief	47.9942117	85.1667483	401
II-28	Zaisan district, vicinity of the village of Buran	Overgrowing dunes	47.9899033	85.1641500	405
II-29	Kurchum district, vicinity of the village of Buran	Leveled riverbed terrace	47.998004	85.158507	399
II-30	Kurchum district, vicinity of the village of Buran	Flat area	47.9999516	85.1556099	401
II-31	Kurchum district, vicinity of the village of Buran	Plain, with salt marshes in places	48.0022450	85.1551467	402
III-1	Kurchum district, vicinity of the village of Shengeldi	River valley with ledges. Relief lined with gullies	47.9122100	84.9164483	391
III-2	Kurchum district, vicinity of the village of Shengeldi	Sand dunes	47.9132403	84.91883305	395
III-3	Kurchum district, vicinity of the village of Shengeldi	A site with complex terrain with numerous depressions	47.9143422	84.9180269	397
III-4	Kurchum district, vicinity of the village of Shengeldi	Hilly area	47.9155917	84.91813383	395
III-5	Kurchum district, vicinity of the village of Shengeldi	Plain upland	47.9167741	84.9170929	391
III-6	Kurchum district, vicinity of the village of Shengeldi	Sand mound	47.9175623	84.9172626	403
III-7	Kurchum district, vicinity of the village of Shengeldi	Swampy depression	47.9191000	84.9174441	397
III-8	Kurchum district, vicinity of the village of Shengeldi	High Plain	47.9214033	84.9203383	395
III-13	Zaisan district, vicinity of the village of Kalihan	Sandy slopes of the river bed	47.9114516	84.8984000	392
III-14	Zaisan district, vicinity of the village of Kalihan	Flat area with slight depressions in the river valley	47.9117017	84.8999333	393
III-15	Zaisan district, vicinity of the village of Kalihan	Sandy hill	47.9109650	84.9022357	394
III-16	Zaisan district, vicinity of the village of Kalihan	Hilly terrain, overgrown dunes with many depressions	47.9127783	84.9074900	392
III-17	Zaisan district, vicinity of the village of Kalihan	Hills and sand dunes	47.9103350	84.9108817	392
III-18	Zaisan district, vicinity of the village of Kalihan	River tributary valley	47.9090685	84.9114517	391
III-19	Zaisan district, vicinity of the village of Kalihan	Plain	47.9070018	84.9117910	391

Table 2

Dominant plant families in the wild flora of the Black Irtysh River valley identified through herbarium records (A) and field expedition surveys (B).

Herbarium Records			Field Expedition Surveys
Family	Number of Species	%	Family	Number of Species	%
Amaranthaceae	58	15	Asteraceae	27	12
Asteraceae	43	11	Caryophyllaceae	19	9
Poaceae	42	11	Fabaceae	16	7
Fabaceae	38	10	Poaceae	15	7
Polygonaceae	26	7	Rosaceae	12	6
Salicaceae	14	3	Amaranthaceae	12	6
Amaryllidaceae	13	3	Polygonaceae	11	5
Ranunculaceae	13	3	Brassicaceae	10	5
Cyperaceae	11	2	Scrophulariaceae	9	4
Lamiaceae	10	2	Ranunculaceae	9	4

Table 3

Locations of rare and endangered plant species in the Black Irtysh valley.

Species Name and Status	Geographical Coordinates	Location	Status of the Species in the Red Book of Kazakhstan	Status of the Species in the Red Book of the Altai Region (Adjacent Region)	Status of the Species in the Red Book of China (Adjacent Region)	Status of the Species in the IUCN
Gagea fedschenkoana Pasche, relict endemic	47.9162583 N84.9254717 E396 m.a.s.l.	East Kazakhstan region, valley of the Black Irtysh river, outskirts of the village of Shingeldy, highway Buran—Shingeldy, on the sand, under the canopy of Populus nigra	–	–	–	–
Tulipa altaica Pall.ex Spreng., Rare species, Altai-Tarbagatai endemic	48.1298738 N84.5001050 E488 m.a.s.l.	East Kazakhstan region, Kurchum district, Kiin-Kerish, on clay rocks	–	V	–	LC
Tulipa patens C.Agardh ex Schult. Schult., Central Kazakhstan-South Altai-Zaisan endemic, Red Data Book of Kazakhstan	47.6856682 N84.0902983 E554 m.a.s.l.	East Kazakhstan region, Aksuat rural district, outskirts of the village of Kazakhstan, gravelly slopes	III	R	–	LC
	48.1726550 N84.8276567 E503 m.a.s.l.	East Kazakhstan region, Kurchum district, Kurchum—Markakol highway, on gravelly steppes, vicinity of the village of Takyr
	47.8933529 N85.0018495 E392 m.a.s.l.	East Kazakhstan region, valley of the Black Irtysh river, western point, sandy slopes
Tulipa uniflora (L.) Besser Backer,Rare species, Red Book of Kazakhstan	47.9870410 N83.2427045 E393 m.a.s.l.	East Kazakhstan region, Aksuat rural district, vicinity of the village of Akmektep, Kalbatau Maykapchagai highway, gravelly slopes	III	V	VU	NT

III indicates the level of protection, V: Vulnerable, R: Rare, VU: Vulnerable, LC: least concern, NT: near threatened.

Table 4

Dominating genera by species diversity based on the survey of herbarium archives and expeditionary results.

Herbarium Archives			Expeditionary Results
Genus	Number of Species	%	Genus	Number of Species	%
Artemisia	14	5	Artemisia	7	3
Allium	13	5	Silene	6	2
Astragalus	12	4	Salix	5	2
Stipa	9	3	Populus	4	2
Potamogeton	8	3	Equisetum	3	1
Sueda	6	2	Nuphar	3	1
Salix	5	2	Thalictrum	3	1
Polygonum	5	2	Clematis	3	1
Leymus	4	1	Rumex	3	1
Anabasis	4	1	Allium	3	1

Table 5

Leading families in the flora of the Black Irtysh compared to the flora of the Zaisan depression and the flora of the Kazakhstan Altai.

Family	Flora of the Black Irtysh Valley		Flora of the Zaisan Depression		Flora of Kazakhstan Altai
	Number of Species/Percentage of the Total Number of Species	Number of Genera/Percentage of the Total Number of Genera	Number of Species/Percentage of the Total Number of Species	Number of Genera/Percentage of the Total Number of Genera	Number of Species/Percentage of the Total Number of Species	Number of Genera/Percentage of the Total Number of Genera
Asteraceae	27/12.4%	15/10.7%	195/15.9%	57/12.6%	324/13.3%	82/11.9%
Caryophyllaceae	19/8.7%	12/8.6%	48/3.9%	21/4.6%	81/3.3%	25/3.6%
Polygonaceae	11/5.0%	6/4.3%	45/3.6%	6/1.3%	40/1.6%	12/1.7%
Brassicaceae	10/4,6%	9/6.4%	73/5.9%	42/9.3%	120/5.2%	56/8.1%
Rosaceae	12/5.5%	9/6.4%	38/3.1%	15/3.3%	109/4.5%	28/4.0%
Fabaceae	16/7.3%	9/6.4%	101/8.2%	22/4.9%	183/7.5%	24/3.5%
Scrophulariaceae	9/4.1%	5/3.6%	34/2.7%	11/2.4%	71/2.9%	15/2.1%
Amaranthaceae	12/5.5%	7/5.0%	99/8.1%	32/7.1%	60/2.5%	19/2.7%
Poaceae	15/6.9%	13/9.3%	98/8.0%	38/8.4%	308/12.6%	62/8.9%
Ranunculaceae	9/4.1%	4/2.8%	20/1.6%	8/1.7%	103/4.2%	26/3.7%
Total	140/64.1%	89/63.5%	751/61%	252/55.6%	1399/57.6%	349/50.2%

Table 6

Types and levels of disturbance of plant communities in the valley of the Black Irtysh River.

Type of Impact	Degree of Impairment	Points
Uncontrolled grazing of livestock	Medium	-
	Strong	III-1, III-2, III-3, III-4, III-5, III-6, III-7, III-8
	Very strong	I-9, I-10, I-11, I-12
	Catastrophic	-
Numerous fires, burnt sites and downed trees	Low	-
	Medium	I-25
	Strong	I-20, I-21, I-22, I-23, I-24
Overgrazing by cattle	Low, local	-
	Medium	II-30, II-31
	Strong	II-26, II-27, II-28, II-29
	Catastrophic	-
Illegal logging	Low	-
	Medium	-
	Strong	III-13, III-14, III-15, III-16, III-17, III-18, III-19
	Very strong	-
	Catastrophic	-

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/d16100641/s1, Table S1: Species diversity of the Black Irtysh flora based on expeditionary survey. Table S2: Results of field survey by profile points.

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