The study of the state and economic value of pasture ecosystems in Mongolia in the context of their progressive degradation continues to be very relevant. The existing methods of forage assessment of pastures are either laborious (the zootechnical method) or do not reflect the real situation (assessment of overall productivity) in the formation of low-species or monodominant degraded communities. To determine the nutritional value and productivity of pasture ecosystems in Mongolia, the palatability coefficient (PC) is proposed, which is determined on the basis of data on the nutritional usefulness of plant species that make up the community, as well as the diversity of eaten species. The PC was calculated as the ratio of the phytomass eaten to the total aboveground phytomass, multiplied by the number of eaten species included in the composition of dominants and codominants. The PC was determined for 158 communities of meadow and steppe pasture ecosystems. These were ranked in four categories. It has been established that a significant part of the studied communities have a high PC. Although these communities are characterized by varying degrees of anthropogenic disturbance, including severe ones, the high PC is due to the fact that some of the digressively active species have satisfactory or good palatability. This fact probably supports the potential for an increase in the number of livestock in Mongolia, which have a wide range of food preferences. At the same time, there is a high proportion of pastures with low and very low PCs. To a greater extent, such pastures are formed by communities of real and dry steppes, which experience the greatest pasture load in Mongolia.

The frequent occurrence of extreme climate events has become an indisputable fact. However, the role of adaptation to extreme climate change in the development of livestock husbandry is still insufficiently understood. This study empirically analyzed the impact of herders' adaptation strategies to extreme drought on livestock husbandry development and aimed to explore the optimal grassland management path under continuous climate change. A panel dataset of surveyed herders from the Xilingol League, a traditional pastoral area in China, was used. The results indicated that the average frequency of extreme drought in the Xilingol League from 1980 to 2020 was 4.94 months/year, and the occurrence of extreme drought showed a slightly upward trend. The average technical efficiency of livestock husbandry was 0.721, which can still be improved. Hay purchases can effectively promote livestock technical efficiency (p<0.01) and is the main adaptation strategy of herders to extreme drought. Further analysis showed that non-farming and pastoral employment has a positive regulatory effect in the impact of purchased hay on livestock technical efficiency. The results of this study deepen the understanding of effective adaptation to extreme weather events in pastoral areas due to climate change and provide useful information to policymakers engaged in grassland management.

The central agricultural region is relatively pleasant in terms of nature and climate of our country, and due to the use of land for multiple purposes, the ecological status of the land has been greatly changed. It is necessary to use many types of layered data and use many types of thematic image results in agricultural monitoring and research, which is a necessary land use. These data will be carried out by various branches of research, and the modelling of each data into a unified database with geographical connections will allow for integrated evaluation and thematic drawing, and the use of geo-spatial analysis decision-making system is required. The purpose of this work is to carry out agricultural land monitoring research using remote sensing methods and advanced technology, to develop a unified methodology, to enrich the data of the points of the monitoring network database, to create an interdisciplinary geo-database, and to develop recommendations for further measures to be taken. It will cover 304,000 hectares of 17 soums of Selenge province and 36,000 agricultural lands of 3 soums of Darkhan-Uul province. A geodatabase was created for the monitoring survey of agricultural land, and a map and route for the field survey was prepared before starting the field survey. The database includes 21 sub-district boundaries, team boundaries and agricultural monitoring points, cadastral data of cultivated and agricultural land, agricultural soil data, satellite data and topography data.

Vegetation cover has a noticeable effect on surface reflectivity and local microclimate in arid areas of Mongolian Gobi. Over the past decades, various shrub species (Haloxylon ammodendron and Calligonum mongolicum) have appeared on the previously unvegetated hamada. The climatic consequences of bush encroachment are still poorly understood. Using the experimental data, this article estimates the reflectance of plants dominating in Mongolia’s dry steppe, desert-steppe, and desert ecosystems. The average values of the total reflection coefficient at visible and infrared wavelengths range from 19.7% ± 1.4% to 20.1% ± 1.7% in plants growing in desert-steppe ecosystems, and from 25.0% ± 0.9% to 24.8% ± 1.5% on the bare surface. The difference between the reflectance of vegetated and unvegetated surfaces reaches 5%. Therefore, in daylight hours, the vegetated day surface loses less solar energy than the non-vegetated surface does. This phenomenon may be defined as a quasi- or secondary greenhouse effect – in daylight hours, solar energy is retained on the surface by vegetation and this contributes to the temperature increase. Such an impulse, which seems to be insignificantly small at first glance, triggers a series of climatic variations leading to a change in the structure of the radiation and heat balance as well as the climate not only in the desert-steppe and desert ecosystems but also in Central Asia as a whole. All this may explain the 1.2-2.3°C increase in air temperatures in the Gobi observed over the last 25 years.

The studies of the steppe ecosystems in Central Mongolia have showed that the simplification of steppe communities has taken place over recent decades. This occurred by reduction of species diversity and abundance of indigenous dominants—tussock grasses—as a result of sharp rise in pasture loads and a long dry period. We have identified two types of introduction of invasive species from different landscapes: (a) extraand intrazonal and (b) zonal. The first type of succession is characterized by focal distribution of Ephedra sinica from ecosystems of low mountains to the surrounding mountain plains. The second type of succession in dry steppes is associated with the expansion of Allium polyrrhizum, whose distribution has largely a frontal character and is caused by weakening of the competitiveness of indigenous species of grass communities because of their significant digression. A further factor in ensuring the conditions for invasion is the aeolian alkalization of the upper horizons of zonal chestnut soils. The ecological and biological features of these two species, widespread in the desert-steppe and desert landscapes and penetrating into the steppe ecosystems, make it possible to speak about biological desertification. The wide area of Ephedra sinica and Allium polyrrhizum indicates a progressive character of the studied types of succession, and as a result of this, the borders of these areas have reached at present the southern periphery of the Baikal Lake basin. The paper describes the processes which lead to the reduction of the fodder value of pastures and jeopardize the maintenance of cattle breeding in Central Mongolia.

The article describes the regional features of ecosystem desertification in the southern periphery of the Baikal basin that are located in the zone of cross-border interaction between the southern Siberian and the Central Asian internal drainage basin landscapes. The nature of such interactions is identified as invasive, which is associated with the penetration of desert-steppe plant species: Caragana bungei are found in larch forests, and Allium polyrrhizum are found in dry steppes. A high degree of species adaptation to the modern arid climate is defined by ecological and physiological analysis of these species characteristics. The significant predominance of Caragana bungei and Allium polyrrhizum in the current structure of plant communities makes it possible to identify a long-term and widespread invasive succession and to characterize this process as a specific desertification form.

About 40 % of the population of Mongolia is involved in nomadic pastoralism. Thus, maintaining productive pasture through regulation is an important topic of research. To gain a better understanding of the ecological interactions between pasture plants and livestock, we conducted a field study of Mongolian pasturelands. We found that intermediate disturbance by livestock grazing maximized both species richness and annual productivity of pasture plants, although the optimal intensity of grazing differs with soil moisture and fecundity. However, too intensive continuous grazing decreases plant species richness and aboveground annual production within several years. Intensive grazing may lead to nearly irreversible changes associated with dominance of grazing-tolerant plants unpalatable to animals and soil alkalization. Pasture degradation is often attributed to a recent increase in goats kept for cashmere production. We confirmed some difference in food preferences between goats and sheep, but both can cause severe damage to pasture plants.

To examine the effects of different pressures by livestock grazing on plant production and species diversity, we conducted mowing experiments using pasture plants at different heights and intervals in an exclosure in a flat valley bottom with high production and on an upper slope with low production in a Mongolian pasture. We transported the trimmings of pasture plants to the laboratory and weighed them. Mowing of pasture plants at different intervals revealed that the optimal annual production occurred when mowing was conducted at intermediate intervals of 30 days. Monthly mowing at heights of 3 and 5 cm revealed higher annual production for the 5-cm height in the flat valley bottom and for the 3-cm height on the upper slope. In another series of experiments, mowing at heights of 0 and 3 cm and at different intervals for 4 years revealed higher annual production and species diversity following mowing at 3 cm in the fourth year. Our results suggest that the annual production and species diversity of pasture plants is optimized by intermediate pressure from livestock grazing.

The features of the present distribution and cenotic association of ephedra (Ephedra sinica Stapf.) in the arid steppe ecosystems of Central and Eastern Mongolia are studied on the basis of data of large-scale investigations performed at the Bayan-Unzhul and Tumentsogt stations within the framework of a Joint Russian-Mongolian complex biological expedition of the Russian and Mongolian Academies of Sciences. The cenotic role of ephedra is revealed according to its correlation with the basic parameters of plant communities (the aboveground phytomass and the abundance of perennial and eutherophyte (annual) species in the ground layer). Plant communities with the dominating role of Ephedra sinica have been formed in degraded arid steppe ecosystems of Mongolia within the last few decades. The ephedra status in these communities can vary depending on the atmospheric humidity.

We examined vegetation interactions throughout the Mongolian ecosystem network to understand its present status. The existing forest mosaic in the forest-steppe zone is the result of the combined effects of climate, slope direction, livestock grazing and browsing, and human activities. Pasture production was positively correlated with precipitation, and at least 10 mm over a period of 15 days is required for good pasture plant production. Mixing with grazing-tolerant plants is not a disadvantage for edible plants in terms of production in the drier habitat. Coverage of grazing-tolerant plants increased with soil alkalization caused by pasture degradation. The recovery of edible pasture plant species diversity after removing disturbances, such as overgrazing and farming, depends on the degree of soil alkalization. In dry regions, shrubs contribute more to livestock nutrition than do herbs because of their production is higher and more consistent. Soil texture, whether sand or silt, affects shrub distribution. The taproot depth of Caragana species was especially deep compared with other shrubs. Human activities contribute to shrub disappearance in pastureland. Moreover, shrub patch degradation accelerates wind erosion in pastures. In the Caragana site, goats preferred Caragana leaves but sheep chose herbs, especially Stipa. Both goats and sheep grazed Caragana leaves completely and even ate the underground parts of herbs under strong hunger.

The present state of the dry-steppe vegetation cover is considered on the example of Central Mongolia, including the structure of plant communities and the vitality of dominant species at the time of peak vegetation and in a winter period. Data on the plant communities have revealed the dominance of Ephedra sinica, a small xeromorphic shrub, and a sizeable decrease in the share of the tussocky graminoid Stipa krylovii, of which the majority of specimens was found in a state of inactivity. Due to the intensification of grazing and a prolonged period of soil-moisture deficiency, the response of Stipa krylovii tussocks to an artificial water supply was insignificant.

The research shows that widely used key measures of vegetation structure (species diversity, projected cover and above-ground phytomass) are not always suitable as indicators of pasture degradation. Based on an analysis above-ground phytomass composition, new quantitative indices are offered that give a more realistic picture of rangeland condition in Mongolia.