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Багш ажилтан
Mongolia is one of the growing Asian countries. Migration, and concentration of the population have led to urban development problems, and the urgent need to provide housing to citizens is increasing. As a result, small lakes in cities are formed by using gravel deposits located near river beds in the surrounding area of the city for the construction of buildings, structures and roads. We've been doing research of seasonal variation of water quality parameters, nutrients and trace metals, their vertical profile in one of these artificial lakes, Lake Bulan. Small lakes located near urban areas can play an important role in the ecosystem and have a positive impact in urban environment. In this sense, studying the water quality and biological pollution of Bulan Lake is important for the protection of the lake's ecosystem. This is the first seasonal observation study on nutrient dynamics undertaken in a small freshwater lake with eutrophication in Mongolia. Water samples were collected seasonally from 3 site in the lake from September 2019 to August 2022. The WQI /water quality index/ was 46.4+0.79 that indicated as polluted. The average concentration of dissolved inorganic nitrogen (DIN) in the surface lake water had a wide seasonal variation from 0.26 ± 0.11 mg N/l in August to 1.44±0.08 mg N/l in January. Seasonal differences were also observed in the vertical profiles. Concentrations were relatively similar at the various water depths in April and September at turnover time. Thermal stratification was observed when the lake was covered in ice, with the maximum concentrations being observed in the bottom layer in the months of January and August. Results indicated that both the summer and winter stratifications are important for regeneration of nutrients in the bottom layer, biochemical cycling in small and shallow lakes in Mongolia.
This is the first seasonal observation study on nutrient dynamics undertaken in a small freshwater lake with eutrophication in Mongolia. The vertical profile and seasonal fluctuation of nutrients are crucial to understanding the biogeochemical cycles in aquatic systems. In this study, field research was carried out at a small and shallow lake, Lake Bulan, in the lower Kharaa River basin. The area has been receiving increased nutrient loads from the water catchment area for the last 20 years. Water samples were collected seasonally from the lake from 2019-2022 and analyzed for nutrients, major cations, trace metals, and dissolved organic carbon. The average concentration of dissolved inorganic nitrogen (DIN) in the surface lake water had a wide seasonal variation from 0.26 ± 0.11 mg N/L in August to 1.44 ± 0.08 mg N/L in January. Seasonal differences were also observed in the vertical profiles. Concentrations were relatively similar at the various water depths in April and September at turnover time. Thermal stratification was observed when the lake was covered in ice, with the maximum concentrations being observed in the bottom layer in the months of January and August. The phosphate concentration showed a similar variation trend. These results indicate that both the summer and winter stratifications are important for regeneration of nutrients in the bottom layer, biochemical cycling, and mitigating impacts of global warming on small and shallow lakes in Mongolia.
Mongolia is in the hinterland of the Mongolian Plateau, which has a varied, fragile, and sensitive geographical environment. Understanding its land cover pattern and change is of great significance for the resources, environment, ecology, and sustainable development of the Mongolia Plateau and Northeast Asia. In this study, land cover products of Mongolia in 1990 and 2010 were obtained via Landsat thematic mapper remote sensing images using an object-oriented classification method. The overall classification accuracies were 82.26% and 92.34%, respectively. Based on the products, the land cover patterns of Mongolia in 2010 and the land cover changes from 1990 to 2010 were analyzed. The spatial pattern presented an obvious regional difference and a land cover type transition from forests, real steppes, and desert steppes to barren from north to south. The provinces with the highest grassland and forest cover were Dornod in Eastern Mongolia and Selenge in Northern Mongolia. From 1990 to 2010, the area of forest, real steppe, cropland, and sand presented a decreasing trend and decreased by 27337.47, 24071.44, 5256.6, and 3868.16 km2, respectively. The area of meadow steppe, desert steppe, bare land, and desert showed an increasing trend and increased by 2943.32, 27815.71, 27721.03, and 2110.26 km2. Our results indicate that the vegetative cover of Mongolia showed a decreasing trend, and the desertification was severe. These changes could be attributed to a combination of climate change, increased livestock grazing and natural disasters, socioeconomic shifts, and exhaustive exploitation of natural resources.
Desertification and land degradation are one of the biggest challenges in the world and are the ecological integrity of nature, society and economy. In recent years, this process is being considered as the same as changes in climate change, air pollution, and biodiversity. The study also summarizes the climate and weather conditions in soums along the border and infrastructure of the Dornod and Selenge provinces. In Dornod aimag: Kherlen, Bayantumen, Bayan-Uul, Gurvanzagal, Dashbalbar, Sergelen and Chuluunkhoroot soums; Selenge aimag: Altanbulag, Sukhbaatar and Shaamar soum. A total of 73 households were selected from 8358 households in Selenge aimag, Sukhbaatar and Shaamar soums of Selenge aimag and conducted a socio-economic survey. A total of 240 households were randomly selected from 19,148 households in the Kherlen, Bayandun, Bayantumen, Bayan-Uul, Gurvanzagal, Dashbalbar, Sergelen, Choibalsan and Chuluunhoroot soums of Dornod aimag. Key words: socio-economic, population migration, desertification, education, health, mining
