7 research outputs found

    Algorithm of Assessment of the MODIS NDVI Long-Term Variations

    Get PDF
    Разработан алгоритм оценки долговременных вариаций характеристик растительного покрова, использующий значения вегетационного индекса NDVI спектрорадиометра MODIS спутников Terra и Aqua. Алгоритм содержит процедуры предварительной обработки данных – восстановление отсутствующих значений, сглаживание фильтром Савицкого-Голея. Для анализа территорий со снежным покровом определяется минимальная длина вегетационного периода для всей длины временного ряда. Полученные после удаления сезонной компоненты значения NDVI используются для построения линейной регрессии и определения тренда. В результате применения алгоритма создана карта пространственного распределения линейных трендов NDVI с 2000 по 2016 гг. для территории Западного Забайкалья. Представлены примеры визуальной верификации изменения растительного покрова с использованием спутниковых изображений сверхвысокого пространственного разрешенияAn algorithm was developed for assessment of long-term variations of vegetation characteristics. The algorithm use NDVI data from spectroradiometer MODIS of Terra and Aqua satellites. The algorithm includes pre-processing procedures – the restoration of missing values, smoothing using Savitsky-Golay filter. To analyze the areas with snow cover the minimum length of the growing season is determined for the full length of the time series. Obtained after removing the seasonal component NDVI values are used to construct a linear regression and determine the trend. As a result of applying the algorithm the map of the spatial distribution of NDVI linear trends was created from 2000 to 2016 for the West Transbaikalia. Examples of visual verification of vegetation cover changes using satellite images of ultra-high spatial resolution are presente

    Environmental Conditions Of Zakamensk Town (Dzhida River Basin Hotspot)

    Get PDF
    Ecological problems of Zakamensk town are associated with sand deposits that were formed as a result of mining activities of former Dzhidinsky tungstenmolybdenum plant. Sands are accumulated in large quantities and they contain dangerous concentrations of heavy metals. Desertification in an urbanized area is manifested locally, but it differs from agricultural desertification by a profound and comprehensive destructive change in the components of the environment. Maps of soils, vegetation, types of lands, as well as ecological zoning maps of Zakamensk were created. The basis for the creation of electronic maps using GIS were stock, archive and own materials, topographic maps and remote sensing data. Urbanized desertification in Zakamensk is caused by chemical contamination of sandy eluvium, the spreading of pollutants by water flows and wind currents. Erosion occurs both in the form of flat flushing and linear erosion. The most intensive is gully erosion. Quantitative parameters of temporal variability of the erosive rainfall potential for the Zakamensk town are received. The quantitative characteristics of loads of pollutants on the territory of the town are determined on the basis of the erosion-deflation models. The calculations showed that 204 tons/ha of contaminated sand annually falls into the settlement area with water-erosion flows (Pb – 3.7 tons, W – 4.3 tons). Moreover, active wind activity led to the deposition of more metals (Pb – 5.6 tons, W – 6.5 tons) in the town

    Algorithm of Assessment of the MODIS NDVI Long-Term Variations

    No full text
    Разработан алгоритм оценки долговременных вариаций характеристик растительного покрова, использующий значения вегетационного индекса NDVI спектрорадиометра MODIS спутников Terra и Aqua. Алгоритм содержит процедуры предварительной обработки данных – восстановление отсутствующих значений, сглаживание фильтром Савицкого-Голея. Для анализа территорий со снежным покровом определяется минимальная длина вегетационного периода для всей длины временного ряда. Полученные после удаления сезонной компоненты значения NDVI используются для построения линейной регрессии и определения тренда. В результате применения алгоритма создана карта пространственного распределения линейных трендов NDVI с 2000 по 2016 гг. для территории Западного Забайкалья. Представлены примеры визуальной верификации изменения растительного покрова с использованием спутниковых изображений сверхвысокого пространственного разрешенияAn algorithm was developed for assessment of long-term variations of vegetation characteristics. The algorithm use NDVI data from spectroradiometer MODIS of Terra and Aqua satellites. The algorithm includes pre-processing procedures – the restoration of missing values, smoothing using Savitsky-Golay filter. To analyze the areas with snow cover the minimum length of the growing season is determined for the full length of the time series. Obtained after removing the seasonal component NDVI values are used to construct a linear regression and determine the trend. As a result of applying the algorithm the map of the spatial distribution of NDVI linear trends was created from 2000 to 2016 for the West Transbaikalia. Examples of visual verification of vegetation cover changes using satellite images of ultra-high spatial resolution are presente

    Estimation of Anthropogenic Forest Disturbancy Using Modis Ndvi Data (on the Example of Zaigraevskoe Forestry, Republic of Buryatia)

    Get PDF
    В работе представлены результаты оценки изменения лесного покрова после природно- антропогенного воздействия (пожары, рубки) на примере модельного участка, а также сравнительный анализ результатов, полученных по статистическим архивным данным и данным дистанционного зондирования. Выявлено, что по снимкам MODIS детектируются только крупные лесные пожары и сплошные рубки леса большой протяженности. Также обнаружено, что не детектируются разнесенные в пространстве небольшие рубки в пределах пикселяThe paper presents the results of assessment the forest cover changes as a result of natural and anthropogenic impact (fires, forest felling) by the example of a model area. A comparative analysis of the results obtained from statistical archival data and remote sensing data was conducted. It has been revealed that according to MODIS images only large forest fires and continuous long-length felling of forests are detected. It has also been discovered that small felling within a pixel is not detecte

    Trend Analysis of Precipitation, Runoff and Major Ions for the Russian Part of the Selenga River Basin

    No full text
    At present, the problem of climate change is becoming increasingly acute. This is especially pressing for Lake Baikal, a World Natural Heritage site. The Russian part of the Selenga watershed is a suitable site for climate change research. The study of changes in precipitation, runoff, and chemical runoff is important for sustainable water resources management. This study presents a trend analysis of precipitation and runoff at hydrological stations and weather stations in the Russian part of the Selenga River basin. A comparative analysis of the concentrations of major ions in the surface water of the Selenga River depending on water levels was also carried out. Analysis of the data series on precipitation revealed a slight negative trend at the Novoselenginsk, Ulan-Ude, and Kabansk stations, and a weak positive trend—at the Kyakhta station. Runoff analysis revealed negative trends at the two used stations (Novoselenginsk and Mostovoi). The hydrochemical regime of the Selenga River is characterized by an increase in major ions and salinity during winter low-water periods, and a decrease during high-water periods. Mineralization and major ion content are lower in the high-water period (2019–2021) than in the low-water period (2015–2017)

    Dendrochronological Study of a 19th-Century Log Cabin (the Ethnographic Museum of Peoples of Transbaikalia, Buryatia)

    Get PDF
    Метод дендрохронологического анализа широко используется для датирования исторических деревянных построек. По сравнению с европейской частью России дендрохронологические исследования археологических и исторических объектов в Сибири начали развиваться лишь в последние десятилетия. При этом до сих пор обширный регион Забайкалья в данном отношении остается малоизученным. В настоящей работе приводятся результаты датирования этапного амбара – экспоната Этнографического музея народов Забайкалья. Отбор древесных кернов (всего 40 образцов с внешних, внутренних стен и потолочного перекрытия дома) и последующий анализ выявили, что часть деревьев, использованных для постройки амбара, срублены в период с ноября 1828 г. по март 1829 г. Предположительный год строительства 1829 г. Таким образом, удалось уточнить дату постройки амбара, который по учетным записям музея датируется серединой XIX в. На основании полученных данных и анализа исторических хроник сделано предположение, что этапный амбар построен, в том числе, для этапирования декабристов. Дендрохронологический материал, собранный с этапного амбара, позволяет существенно продлевать региональные шкалы для датировки исторической древесины и получить новую информацию о цикличности режима увлажнения в бассейне оз. Байкал. Планируется расширить аналогичные исследования на другие объекты историко-культурного наследия ЗабайкальяThe method of dendrochronological analysis, or tree-ring dating, is widely used for dating historical wooden buildings. In contrast to the European part of Russia, dendrochronological research of archaeological and historical wood in Siberia has begun only in recent decades. For this reason, few studies have been conducted in the vast region of Transbaikalia. This paper presents the results of dating of a log cabin used as an exile transit station preserved as an exhibit in the Ethnographic Museum of Peoples of Transbaikalia. An analysis of selected wood core samples (total 40 samples from the external and internal walls and the ceiling) revealed that some of the trees used for the building of the cabin were felled between November 1828 and March 1829. Thus, we managed to ascertain the date of the construction of the cabin, which according to the records of the museum dates back to the mid‑19th century. The dendrochronological material collected from the log cabin allowed to extend significantly the regional scales for historical timber dating, and to obtain new information about moisture cycles of the Lake Baikal basin. Further studies of other sites of historical and cultural heritage of Transbaikalia are planne

    Atmospheric Air Pollution by Stationary Sources in Ulan-Ude (Buryatia, Russia) and Its Impact on Public Health

    No full text
    For the first time in the territory of the Russian Far East, a study related to the establishment of correlations between air quality and public health in Ulan-Ude (Buryatia, Russia) was carried out. This study is based on the analysis of official medical statistics on morbidity over several years, the data on the composition and volume of emissions of harmful substances into the air from various stationary sources, and laboratory measurements of air pollutants in different locations in Ulan-Ude. This study confirmed that the morbidity of the population in Ulan-Ude has been increasing every year and it is largely influenced by air pollutants, the main of which are benzo(a)pyrene, suspended solids, PM2.5, PM10, and nitrogen dioxide. It was found that the greatest contribution to the unfavorable environmental situation is made by three types of stationary sources: large heating networks, autonomous sources (enterprises and small businesses), and individual households. The main air pollutants whose concentrations exceed the limits are benzo(a)pyrene, formaldehyde, suspended particles PM2.5, PM10, and nitrogen dioxide. A comprehensive assessment of the content of various pollutants in the atmospheric air showed that levels of carcinogenic and non-carcinogenic risks to public health exceeded allowable levels. Priority pollutants in the atmosphere of Ulan-Ude whose concentrations create unacceptable levels of risk to public health are benzo(a)pyrene, suspended solids, nitrogen dioxide, PM2.5, PM10, formaldehyde, and black carbon. The levels of morbidity in Ulan-Ude were higher than the average for Buryatia by the main disease classes: respiratory organs—by 1.19 times, endocrine system—by 1.25 times, circulatory system—by 1.11 times, eye diseases—by 1.06 times, neoplasms—by 1.47 times, congenital anomalies, and deformations and chromosomal aberrations—by 1.63 times. There is an increase in the incidence of risk-related diseases of respiratory organs and the circulatory system. A strong correlation was found between this growth of morbidity and atmospheric air pollution in Ulan-Ude
    corecore