Spatial and Temporal Variations of Freezing and Thawing Indices From 1960 to 2020 in Mongolia

Mongolia is one of the most sensitive regions to climate change, located in the transition of several natural and permafrost zones. Long-term trends in air freezing and thawing indices can therefore enhance our understanding of climate change. This study focuses on changes of the spatiotemporal patterns in air freezing and thawing indices over Mongolia from 1960 to 2020, using observations at 30 meteorological stations. Our results shows that the freezing index ranges from −945.5 to −4,793.6°C day, while the thawing index ranges from 1,164.4 to 4,021.3°C day over Mongolia, and their spatial patterns clearly link to the latitude and altitude. During the study period, the trend in the thawing index (14.4°C-day per year) was larger than the trend in the freezing index (up to −10.1°C-day per year), which results in the net increase of air temperature by 2.4°C across Mongolia. Overall, the increase in the thawing index was larger in the low latitudes and altitudes (e.g., the Gobi-desert, steppes, the Great lake depression and major river valleys) than in high latitudes and altitudes (mountain regions), while it was the opposite for the freezing index. The highest values for both thawing index and freezing index (i.e. the least negative values) have occurred during the last 2 decades. As the trends in the freezing and thawing indices and mean annual air temperature confirm intensive climate warming, increased permafrost degradation and shallower seasonally frozen ground are expected throughout Mongolia.

Heavy metal pollution characteristics and health risk assessment of dust fall related to industrial activities in desert steppes

China’s desert steppe is the transition zone between the grasslands in central China and the arid desert. Ecological security in this region has long been a subject of debate, both in the local and academic communities. Heavy metals and other pollutants are readily released during industrial production, combustion, and transportation, aggravating the vulnerability of the desert steppes. To understand the impact of industrial activiteis on the heavy metal content of dust fall in the desert steppe, a total of 37 dust fall samples were collected over 90 days. An inductively-coupled plasma mass spectrometer (NexION 350X) was used to measure the concentration of heavy metals Cu, Cd, Cr, Pb, Mn, Co, and Zn in the dust. Using comprehensive pollution index and multivariate statistical analysis methods, we explored the characteristics and sources of heavy metal pollution. We also quantitatively assessed the carcinogenic risks of heavy metals resulting from dust reduction with the help of health risk assessment models. The heavy metals’ comprehensive pollution index values in the study area’s dust fall were ranked as follows: Zn > Cd > Pb > Mn > Cu > Co > Cr. Among these, Zn, Cd, and Pb were significant pollution factors in the study area, and were affected by industrial production and transportation. The high pollution index was concentrated in the north of the research industrial park and on both sides of a highway. The seven heavy metals’ total non-carcinogenic risk index (HI) values were ranked as follows: Mn > Co > Pb > Zn > Cr > Cu > Cd (only the HI of Mn was greater than one). Excluding Mn, the non-carcinogenic and carcinogenic risk index values of the other six heavy metals were within acceptable ranges. Previous studies have also shown that industrial transportation and production have had a significant impact on the heavy metal content of dust fall in the desert steppe.

BORIS KOSTIANTINOVICH FORTUNATOV (1886–1940?): BIOGRAPHY PAGES

The purpose of the article. The article is devoted to the coverage of the main milestones in the life and work of a prominent zoologist, breeder, ecologist, conservationist, military and political figure, science fiction writer – Boris Konstantinovich Fortunatov (1886–1940?).Results and scientific novelty of the research. On the basis of archival and literary sources, the years of B. Fortunatov's studies and his participation in the Socialist-Revolutionary Party (SR) are considered. His role in the revolutionary events of 1905 and 1917, the First World War and the Civil War is analyzed. It is noted that the first scientific publication of the 25-year-old Fortunatov was devoted to the synthesis of bread. It was found that in 1920, after arriving at the former estate of F. Falz-Fein – Askania-Nova – there were radical changes in the life of B. Fortunatov. From that time until the last days of his life he dealt with environmental protection issues. Thanks to his enthusiasm and persistence that the Askania-Nova Reserve was saved from looting and ruin. Heading first the scientific part of the reserve, and then as the head of the zoo B. Fortunatov conducted research on the revival of the bison population and aurochs; fought robbers; studied the origin of Askanian pheasants; saved the Askanian steppes from ruin. It is noted that in different years he headed the following reserves: Askania-Nova, Crimean, Primorsky, Caucasian; worked at the Moscow Zoo, and even designed a new zoo in this city. It is stated that at the territory of the special settlement he continued his scientific activities. Heading a research station for animal husbandry, the scientist observed the fauna and flora of Saryrki; explored the desert steppes of Central Kazakhstan; organized sheep farms in order to breed fat-tailed sheep; engaged in the improvement of cattle breeds; developed a method and program for new breeds of cattle; justified the need to create the Karkalinsky State Nature Park.Key words: Fortunatov, environmental protection, Askania-Nova, reserves, animal hybridization. Мета роботи. Стаття присвячена висвітленню основних віх життя та діяльності видатного вченого-зоолога, селекціонера, еколога, захисника природи, військового і політичного діяча, письменника-фантаста – Бориса Костянтиновича Фортунатова (1886 – 1940?). Результати та наукова новизна дослідження. На основі архівних та літературних джерел розглянуто роки навчання Б. Фортунатова та його участі партії соціалістів-революціонерів. Показано його роль в революційних подіях 1905 та 1917 рр., Першій світовій та Громадянській війнах. Звернено увагу, що першу наукову публікацію 25-річний Фортунатов присвятив синтезу хліба. З’ясовано, що з 1920 р., після прибуття до колишнього маєтку Ф. Фальц-Фейна – Асканії-Нова – відбулися кардинальні зміни у житті Б. Фортунатова. З цього часу і до останніх днів його життя було пов’язане з охороною природи. Саме завдяки ентузіазму та наполегливості вченого заповідник Асканія-Нова було врятовано від пограбувань та розорення. Очолюючи спочатку наукову частину заповідника, а потім будучи завідувачем зоопарку Б. Фортунатов проводив дослідження з відродження популяції зубра та тура; боровся з браконьєрами; вивчав походження асканійських фазанів; добивався збереження асканійських степів від розорення. Зазначено, що у різні роки він очолював заповідники: Асканія-Нова, Кримський, Приморські, Кавказький; працював у Московському зоопарку, і, навіть, займався проектуванням нового зоопарку у цьому місті. Вказано, що перебуваючи на спецпоселенні він продовжив займатися науковою діяльністю. Очолюючи науково-дослідну станцію з тваринництва вчений проводив спостереження за фауною і флорою Сариркі; досліджував пустельні степи Центрального Казахстану; організував вівчарні з метою виведення курдючної вівці; займався покращенням порід великої рогатої худоби; розробив методику та програму створення нових порід великої рогатої худоби; обґрунтував необхідність створення Каркалінського державного парку природи. Ключові слова: Фортунатов, охорона природи, Асканія-Нова, заповідники, гібридизація тварин.

New and validated names of some syntaxa of the Festuco-Brometea class vegetation from Eastern Europe

We present new and validated names of some syntaxa of the vegetation class Festuco-Brometea. True steppe vegetation of Eastern Europe, which is distributed from the Eastern part of Romania to the Urals, we propose to consider as a separate order Galatello villosae-Stipetalia lessingianae. It is an intermediate link between meso-xeric communities of the Central and Eastern Europe of the order Festucetalia valesiacae Soo 1947 from one hand, and desert steppe vegetation of the order Tanaceto achilleifolii-Stipetalia lessingianae Lysenko et Mucina in Mucina et al. 2016 from the other hand. We describe a new order Cephalario uralensis-Jurineetalia stoechadifolii for rocky dwarf-shrub calcareous grasslands of the Pontic region. It replaces the order Stipo pulcherrimae-Festucetalia pallentis Pop 1968 in Eastern Europe due to more continental conditions. We validate the name of the alliance Galio campanulati-Poion versicoloris, as well as its type association. This alliance includes rocky grasslands on limestone outcrops from the Central and Western Podillia and belongs to the order Stipo pulcherrimae-Festucetalia pallentis Pop 1968 on the easternmost range of its distribution. We describe a new association of the desert steppes from the Republic of Kalmykia of the alliance Tanaceto achilleifolii-Stipion lessingianae. In addition, we publish the replacement name Paeonio tenuifolii-Stipetum tirsae as a substitute for illegitimate later homonym. У статті наводиться опис нових, а також відбувається валідизація деяких синтаксонів рослинності класу Festuco-Brometea. Запропоновано справжні степи Східної Європи, поширені від східної частини Румунії до Уралу, відносити до порядку Galatello villosae-Stipetalia lessingianae. Він є проміжною ланкою між мезоксерофітними угрупованнями Центральної та Східної Європи порядку Festucetalia valesiacae Soo 1947 та пустельними степами порядку Tanaceto achilleifolii-Stipetalia lessingianae Lysenko et Mucina in Mucina et al. 2016. Кальцепетрофітні угруповання Понтичного регіону запропоновано об’єднати у порядок Cephalario uralensis-Jurineetalia stoechadifolii. Вони заміщають ценози Stipo pulcherrimae-Festucetalia pallentis Pop 1968 у Східній Європі в умовах більш континентального клімату. Валідизовано союз Galio campanulati-Poion versicoloris, що охоплює угруповання на карбонатних відслоненнях Центрального та Західного Поділля, і є одиницею порядку Stipo pulcherrimae-Festucetalia pallentis Pop 1968 на східній межі поширення, а також асоціацію, що є його лектотипом. Описано нову асоціацію пустельних степів з Республіки Калмикія з союзу Tanaceto achilleifolii-Stipion lessingianae. Окрім того, наведено нову назву Paeonio tenuifolii-Stipetum tirsae для асоціації лучних кримських степів, оскільки стара її назва має бути відхилена внаслідок омонімії.

Effects of rock fragments on the water infiltration and hydraulic conductivity in the soils of the desert steppes of Inner Mongolia, China

Soils that contain rock fragments (particles > 2 mm in diameter) are distributed all over the world. The presence of these small rock fragments can have a great impact on soil water retention properties, as well as on the soil-water infiltration and vegetation restoration in semi-arid regions. To quantitatively describe the transport of water in stony soils, repacked soil cores were used to determine the infiltration rates for different rock fragment contents (0%, 10%, 20%, 30%, and 40%) and rock fragment sizes (2–5, 5–8, 8–11, and 2–11 mm). The results showed that both the content and size of the rock fragments and their interaction significantly affected the infiltration process. The infiltration rates over time and the saturated hydraulic conductivity (K_s) decreased with an increasing rock fragment content to an observed minimum value for a 40% rock fragment content. The soil-water infiltration processes were accurately described by the Kostiakov model. The measured and calculated K_s values decreased with an increasing rock fragment content, which was in accordance with the published data and in accordance with the K_s obtained by five empirical methods. The variations in the measured K_s were likely due to the variations in the soil properties caused by the soil sample repacking. The results of this study may improve the understanding of the effects of the rock fragment content and size on the infiltration processes in arid and semi-arid desert steppes.

ECOSISTEMS PATTERN OF СENTRAL TUVINIAN BASIN

To analyze the pattern of ecosystems on the territory of the Central Tuvinian Basin the images from the Landsat-8 satellite for the summer period of 2020 were used. Satellite images were processed in the GRASS geographic information system using the SMAP classification method. The basin under study is located in the center of the Republic of Tuva. The region is characterized by a sharply continental climate with low snowy and very cold winters, hot and dry summers. Based on satellite information and the cartographic information, 13 land units were identified in the studied territory of the Central Tuvinian Basin. The total area of the Central Tuvinian Basin is 18.6 thousand km2 . A mosaic ecosystem structure of typical, dry and desert steppes is presented on the flat territory of the basin. Based on the satellite images, a map-scheme for ecosystems pattern on the territory of the Central Tuvinian Basin was made. Steppe vegetation is gradually occupying the abandoned arable lands. The area of cultivated fields in the Central Tuvinian Basin has decreased by 90% over the past 30 years. There was an expansion of the territories of dry and desert steppes with the participation of shrubs of Caragana Bunge. Desertification processes are ongoing in the Central Tuvinian Basin.

Classification of the desert steppes ecosystems of Western Kazakhstan

The results of the steppe zone ecosystems investigation in Western Kazakhstan are presented. Theclassification of the main types of terrestrial ecosystems of the desert steppes subzone, divided by the forms of macrorelief(elevated plains, river valleys, sand massifs) and grouped into categories according to the type of water regime (automorphic,semihydromorphic, hydromorphic), is presented. Within the automorphic category, one zonal class of ecosystems hasbeen distinguished: cereal-wormwood desert steppes on light chestnut soils. The semi-hydromorphic category includesecosystems of wormwood-halophytic-cereal steppe meadows on meadow-chestnut soils. The hydromorphic categoryof river valleys is characterized by ecosystems of floodplain forest-meadow and tree-shrub tugai on floodplain meadowsoils.

Modeling the influence of temperature and water potential on seed germination of Allium tenuissimum L.

Allium tenuissimum L. is a widely distributed perennial herbaceous species in temperate and desert steppes. Relative to other wild Allium species, it produces unique sweet flavors, more biomass in arid and cold environments, and has generated greater interest for crop production. Successful crop establishment, however, will depend on rapid and uniform seed germination. Our study aimed to characterize seed germination of A. tenuissimum under various temperature regimes (11, 15, 20, 24 and 28 °C) and water potential levels (0, −0.2, −0.4 and −0.6 MPa), and model germination by hydrotime (HT) and hydrothermal time (HTT) analysis. Final germination percentage (FGP) increased within the range of 11 to 20 °C, yet it declined within the range of 24 to 28 °C and generally decreased as water potential became more negative within each temperature setting. Maximum FGP was observed at 20 °C at all water potential settings and ranged from 55.0 ± 5.3 to 94.8 ± 1.4%. According to HT and HTT models, the base (Tb) and optimum temperatures (To) for seed germination were 7.0 and 20.5 °C, respectively. In addition, base water potential for the fraction of germination within the seed lot (Ψb(g)) shifted to 0 MPa as temperature increased from Tb to ceiling temperature (Tc). For obtaining 50 % seed germination, Ψb(50) and Tc(50) were estimated to be −0.67 MPa and 27.2 °C, respectively. These values for Tb and Ψb(50) suggest seed germination of A. tenuissimum is both cold and drought tolerant and suitable for production in semi-arid regions. Our characterization of the ideal sowing conditions for A. tenuissimum, i.e., 20.5 °C and soil water potential less negative than −0.67 MPa offers information to forecast suitable settings to enhance crop production.

Assessment of the vulnerability of alpine grasslands on the Qinghai-Tibetan Plateau

Assessing ecosystem vulnerability to climate change is critical for sustainable and adaptive ecosystem management. Alpine grasslands on the Qinghai-Tibetan Plateau are considered to be vulnerable to climate change, yet the ecosystem tends to maintain stability by increasing resilience and decreasing sensitivity. To date, the spatial pattern of grassland vulnerability to climate change and the mechanisms that vegetation applies to mitigate the impacts of climate change on grasslands by altering relevant ecosystem characteristics, especially sensitivity and resilience, remain unknown. In this study, we first assessed the spatial pattern of grassland vulnerability to climate change by integrating exposure, sensitivity, and resilience simultaneously, and then identified its driving forces. The results show that grasslands with high vulnerability were mainly located on the edges of the plateau, whereas alpine grasslands in the hinterlands of the plateau showed a low vulnerability. This spatial pattern of alpine grassland vulnerability was controlled by climatic exposure, and grassland sensitivity and resilience to climate change might also exacerbate or alleviate the degree of vulnerability. Climate change had variable impacts on different grassland types. Desert steppes were more vulnerable to climate change than alpine meadows and alpine steppes because of the high variability in environmental factors and their low ability to recover from perturbations. Our findings also confirm that grazing intensity, a quantitative index of the most important human disturbance on alpine grasslands in this plateau, was significantly correlated with ecosystem vulnerability. Moderate grazing intensity was of benefit for increasing grassland resilience and then subsequently reducing grassland vulnerability. Thus, this study suggests that future assessments of ecosystem vulnerability should not ignore anthropogenic disturbances, which might benefit environmental protection and sustainable management of grasslands on the Qinghai-Tibetan Plateau.

ANALYSIS OF CHANGES IN VEGETATION COVER FOR NORTHERN PART OF UVS NUUR BASIN

To analyze changes in the vegetation cover on the territory of the Russian part of the Uvs Nuur Basin the images from the Landsat-5 and Landsat-8 satellites for the summer periods of 1988 and 2019 were used. Satellite images were processed in the GRASS geographic information system using the SMAP classification method. The Uvs Nuur Basin is located on the border of the Republic of Tuva and Mongolian People’s Republic. The region is characterized by a sharply continental climate with low snowy winters, hot and dry summers. A mosaic landscape structure of typical, dry and desert steppes is presented on the flat territory of the northern part of the Uvs Nuur Basin. Based on satellite information and the cartographic information, 9 landunits were identified in the studied territory of the Uvs Nuur Basin. According to the satellite images, the total area of the Russian part of the Uvs Nuur Basin is 19.5 thousand km2 . Changes in the areas of the selected landunits are estimated as a result of the satellite images classification. From the obtained results it was found that over the past 30 years, the area of cultivated fields in the northern part of the Uvs Nuur Basin has decreased by 80 %. Steppe vegetation is gradually occupying the abandoned arable lands. Desertification processes are ongoing in the Uvs Nuur Basin territory. There was a reduction in the area of meadows and an expansion of the territories of dry and desert steppes with the participation of shrubs of Caragana Bunge.