Analysis Of Aerial Photographs Research Articles

CAMBIOS HISTORICOS EN LA DISTRIBUCIÓN Y ABUNDANCIA DE PRADERAS DE PASTOS MARINOS EN LA BAHÍA DE CARTAGENA Y AREAS ALEDAÑAS (COLOMBIA)

The spatial distribution of seagrass beds within the Cartagena Bay and neighboring areas was reconstructed through comparative analyses of maps, aerial photographs and satellite imagery, as well as observations in the field for five time periods within the last six decades. From slightly more than 1,000 hectares of seagrass beds existing in 1935-45, only 76 remained in 2001, which is less than 8%. The loss rate of seagrass within the bay showed an inverse exponential pattern, whereas outside of the bay the tendency was linear. The almost disappearance of this community was probably raged by the reopening of the Canal del Dique early in the thirties, causing the introduction of important amounts of turbid freshwater and sediments into the bay, and subsequently accelerated by the rapid development of the industrial zone, spilling of polluted industrial and domestic waters, dredging and coastal development. The reduction of seagrass areas has been seemingly accompanied by changes in the structure of the animal community, becomig apparent through the evident disappearance of suspension feeding invertebrates which were so far dominant elements three decades earlier. The loss of seagrass beds in the bay during the 20th century seems likely to be part of the long lasting human transformation process of this ecosystem, which started three centuries before.

The First World War from above and below. Historical aerial photographs and mine craters in the Ypres Salient

During the First World War, ancient siege techniques were used in an attempt to break through the stalemate in the trenches. This paper approaches the mine crater war from a completely new perspective and focuses on a landscape-scale approach rather than on fragmented individual sites. Thousands of contemporary aerial photographs have been used as a primary source of information to detect and understand the historical mine crater landscape along the former Western Front in Belgium. The paper presents a methodology for dating war features by means of a time series analysis of aerial photographs, confronting this historical landscape with a high-resolution Airborne Laser Scanning (ALS) dataset.

Vertical growth in a coastal city: an analysis of Boa Viagem (Recife, Brazil)

Coastal zones around the world have experienced urban growth in the last 50 years. This landscape change brings new aspects for those zones and the environment. Real estate speculation is a decisive factor that changes landscape, with urban growth that occurs both in the extent and volume of construction. Boa Viagem (BV) beach at Recife, Northeast Brazil was just a sand bar covered by an Atlantic Forest until middle of the 1800s. Today, it has turned into a busy area of the city where residences, services and commerce co-exist in a densely packed arrangement. This work demonstrates and analyses vertical growth in BV and urban changes from 1961 to 2011. It was developed using digital image processing and visual analysis of satellite imagery and aerial photos. A GIS was created using SPRING and ArcScene, to calculate variations in area and volume creating a Volumetric Index (VI). The Minimal Mapping Area was used in sixteen census tract as samples of the area. Occupation and vertical growth were especially accentuated from 1981 to 1996 with the peak at 2011. Increases in vertical growth from shore to inland are evident in all parts of the district. This finding was confirmed by three-dimensional GIS representations of the study area and the VI during the period of this work, showing the potential of 3D GIS models for studying dense urbanization areas in coastal zones.

Geomorphology and dynamics of a traveling cuspate foreland, Authie estuary, France

Cuspate forelands or salients occur all over the world in lakes, estuaries and on ocean shores, yet there have been few studies conducted on traveling cuspate forelands (or salients), that is, forelands that migrate or travel alongshore. This paper presents a study of a traveling foreland in the Authie estuary, France, termed the Bec du Perroquet. Historical shoreline changes may be traced from the 1200's AD and the region has experienced both marked intertidal-subtidal accretion extending from the south, and massive erosion in the north since this period. An analysis of aerial photographs from 1947 until the present shows that the original Bec foreland was established at the mouth of the Authie estuary, but gradually disappeared by the 1960's and a new foreland developed in the middle of the northern-central portion of the bay. This foreland was composed of a suite of foredune ridges which have been successively eroded on the northern margin and initiated on the southern margin as the foreland traveled or migrated southwards. As the foreland traveled south, from 1947 to 2009 the northern part of the bay retreated more than 350m, while mid-bay, the coastline retreated ~215m. As the foreland evolves and migrates, incipient foredunes can develop rapidly (e.g. 18 ridges formed in an 11week period), while at other times the ridges form slowly and may be eroded and disappear. Two or more foredune ridges may blend into a single ridge over time depending on the initial degree of vegetation cover on the ridge and swale set. Aeolian processes in dune swales are much more important in this system than in typical prograding foredune plain systems due to the sometimes marked lack of vegetation colonization in the swales following foredune ridge development, and aeolian deflation of the swales (along with blowout development) is important particularly when they become open conduits to the beach as erosion of the NW foreland proceeds. The ages of each of the surviving ridges on the foreland in 2009 have been determined, and the evolutionary path of the ridges ascertained. Formerly intact, relatively stable, continuous ridges evolve to erosional knobs, turrets and nebkha over time. Foredune ridges (and swales) can be extremely arcuate to semi-circular in form where the foreland and especially the spit extension are exposed to a wide range of wind directions and where the shoreline trends through an arc of at least 270°. This study illustrates a remarkable cycling of the formation, destruction and reformation (travel) of a cuspate foreland over a ~50+year period.

Abandoned channel fill sequences in the tidal estuary of a small mountainous, dry‐summer river

AbstractThis study proposes a modification of the current model for abandoned channel fill stratigraphy produced in unidirectional flow river reaches to incorporate seasonal tidal deposition. Evidence supporting this concept came from a study of two consecutive channel abandonment sequences in Ropers Slough of the lower Eel River Estuary in northern California. Aerial photographs showed that Ropers Slough was abandoned around 1943, reoccupied after the 1964 flood, and abandoned again in 1974 with fill continuing to the present. Planform geomorphic characteristics derived from these images were used in conjunction with sub‐centimetre resolution stratigraphic analyses to describe depositional processes and their resultant sedimentary deposits. Both abandonment sequences recorded quasi‐annual scale fluvial/tidal deposition couplets. In both cases, tidal deposits contained very little sand, were higher in organic and inorganic carbon content than the sandier, fluvially dominated deposits, and possessed millimetre‐scale horizontal laminations. The two abandonment fills differed significantly in terms of the temporal progression of channel narrowing and fluvial sediment deposition characteristics. Aerial photographic analysis showed that the first abandonment sequence led to a more rapid narrowing of Ropers Slough and produced deposits with a positive relationship between grain size/deposit thickness and discharge. The second abandonment resulted in a much slower narrowing of Ropers Slough and generally thinner fluvial deposits with no clear relationship between grain size/deposit thickness and discharge. The δ13C values and organic nitrogen to organic carbon ratios of deposits from the first phase overlapped with Eel River suspended sediment characteristics found for low flows (one to five times mean discharge), while those of the second phase were consistent with suspended sediment from higher flows (seven to ten times mean discharge). When considered together, the results indicate that the early fill sequence recorded a reach experiencing regular fluvial deposition through flow conditions during the wet season, while the latter fill sequence records a reach more disconnected from the main stem in terms of flow and sediment. The major factor affecting the difference in sedimentation between the two fill periods appears to have been the morphology of the upstream river bend in relation to the position of the bifurcation node. During the first fill period, the upstream entrance to Ropers Slough seems to have remained open, in part due to the placement of its entrance on the outside of the mainstem river bend, and despite stronger tidal effects caused by a larger tidal prism and closer proximity to the tidal inlet. By the second fill sequence, the upstream bend morphology had altered, placing the entrance to Ropers Slough on the inner bank of the mainstem bend, which resulted in more rapid plug bar formation. The role of tidal effects in the geomorphic trajectory of the two abandonment sequences is unclear, but appears to have been less important than local bifurcation geometry.

Dalle “carte” alla terra. Il paesaggio comacchiese nell’alto medioevo

Starting from the results of the archaeological excavations lead by the Ca’ Foscari University of Venice between 2006 and 2010, this paper offers a reconstruction of the landscape of Comacchio in the early middle ages (7th-10th Century). The emporium of Comacchio was founded in a lagoon area not far from important tributaries of the Po river. The research was based on traditional topographic methods (study of historical cartography and place names, analysis of aerial photography); it also turned to geoarcheology in order to investigate the site of St. Maria in Padovetere .

The potential of integrated GPR survey and aerial photographic analysis of historic urban areas: A case study and digital reconstruction of a Late Roman villa in Durrës (Albania)

This paper focuses on the results of a joint geoarchaeological research project of urban historical remains in the ancient Roman city of Durrës, Albania. The project began with a desk-based analysis of all the historical and archival evidence including aerial photos from the 1920s–40s, a period before major urbanization of the area and prior to the capture of satellite imagery in the 1960s. These aerial photographs were re-processed and then combined with ground-penetrating radar (GPR) imagery and used to locate a Late Roman villa in the city. The integrated results produced a visual idea of what the villa looked like, when analysed in conjunction with the known archaeological and historical literature. During analysis, different levels of data reliability and resolution have been identified, which inform methodological choices when undertaking reconstructions of the villa. These methodological issues have generic resonance in the reconstruction of urban landscapes.

Extracting Pavement Surface Distress Conditions Based on High Spatial Resolution Multispectral Digital Aerial Photography

AbstractState transportation agencies regularly collect data on pavement surface distresses. These data are used to assess overall pavement conditions and to make maintenance and repair decisions. Routinely-acquired and publically-available high spatial resolution (hsr) multispectral digital aerial photography provides a potential method for collecting distress information that can supplement or replace currently-used technologies. Principal component analysis and linear least squares regression models were used to evaluate the potential of using HSR multispectral digital aerial photographs to estimate pavement surface overall distress conditions. Various models were developed using HSR multispectral digital aerial photographs of different spatial resolution (6-inch, 12-inch, and 24-inch) and reference pavement surface distress data collected manually at multiple sample sites using standard protocols. The results show that the spectral response of HSR multispectral digital aerial photographs correlate strongly with reference distress rates at all tested spatial resolutions, but the 6-inch aerial photos exhibit the strongest correlation (R2 > 0.95), even when using only half of the sample sites (R2 > 0.92). These results indicate that straightforward analysis of HSR multispectral digital aerial photographs, routinely acquired by most municipalities and states, can permit assessment of pavement surface distress conditions as well as current manual evaluation protocols.

Elaboración de la base de datos del archivo técnico de la Dirección General de Catastro y Geografía y su importancia en la planificación de la gestión y ordenamiento del territorio en Honduras

Con el desarrollo de este trabajo se logró organizar y generar una base de datos de la información contenida en el Archivo Técnico de la Institución (desde las primeras fotos tomadas, ortofotos, mapas, documentos, etc.). Se escogió en base a la sugerencia de los encargados del Archivo Técnico, el (Proyecto Catastro Nacional 1977) sirviendo este como base y guía para una ampliación del proyecto, con el objetivo de modernizar y tecnificar el archivo técnico de la institución. En la base de datos, se estableció la ubicación física (sobre, número de estante, fila, columna) de cada fotografía aérea del antiguo Proyecto Catastro Nacional 1977. Además en que ND y número de hoja cartográfica está ubicada (base de datos específica para las hojas cartográficas), así como establecer en que rollo de negativos está contenida. Cubriendo e integrando en esta base de datos todos los componentes que forman parte del archivo técnico. Comenzando con el análisis de las fotografías aéreas, ligándolos a los ND, Hojas cartográficas, sobres y rollos de negativos. La información obtenida con el uso de la base de datos del archivo técnico, optimiza el tiempo-recurso de la institución y personal técnico y facilita el desarrollo de investigaciones futuras al facilitar el acceso a la información cartográfica y datos. el desarrollo de este proyecto es vital ya que el material que se encuentra en el archivo técnico y que se ha incorporado en la base de datos es importante para el desarrollo de la Dirección General de Catastro y Geografía. Podemos considerar que entre las aplicaciones del proyecto en la Ordenación Territorial encontramos una relación directa ya que para poder efectuar planificación y ordenación del territorio necesitamos hacer uso de cartografía.Revista Ciencias Espaciales, Volumen 8, Número 2 Otoño, 2015; 152-162

Large-scale geomorphological mapping as a tool to detect structural features: the case of Mt. Prinzera ophiolite rock mass (Northern Apennines, Italy)

ABSTRACTThis paper presents a geomorphologic map of the Mt. Prinzera ultramafic rock complex (Parma Province, Emilia-Romagna Region, Italy) mapped at large scale (1:2500). The map is the first contribution to the detailed geomorphologic knowledge of the area within the framework of a multidisciplinary approach used to analyse Mt. Prinzera as a hard rock aquifer case study. The geomorphologic mapping was carried out by field survey and aerial photograph analysis. All the surface processes and landforms were considered, with particular attention to structural geomorphologic features. The mapping of linear morphologic features was considered useful for revealing the presence of sets of joints otherwise difficult to detect due to surface weathering. Sets of rock discontinuities are important for water seepage and percolation and their identification is crucial for developing the hydrogeological conceptual model of the aquifer.

The use and usefulness of inventory-based management planning to forest management: Evidence from community forestry in Nepal

This paper examines the use and usefulness of inventory-based management planning to practical forest management in processes of community forestry in Nepal. The paper is based on case studies in four Community-Forestry User Groups (CFUG) in the mid-Hills of Nepal and draws upon semi-structured interviews, participatory rural appraisal exercises and analyses of aerial photographs. First, we find that the operational plans supposed to guide community-level management are based on sub-standard forest inventories, which limits their potential role in practical forest management. Second, we find that community-level managers do not rely on the operational plans in their practical forest management. Finally, we find that community-level forest managers in these four cases have managed to conserve their community forests over time and appear knowledgeable about the developments in the condition of their forests in the sense that their impressions of past and current forest condition are mirrored in what we can observe from analysis of change in forest condition based on aerial photographs. Based on these results we question the usefulness of inventory-based management planning in the context of community forestry.

River channel adjustments in Southern Italy over the past 150 years and implications for channel recovery

Multi-temporal GIS analysis of topographic maps and aerial photographs along with topographic and geomorphological surveys are used to assess evolutionary trends and key control factors of channel adjustments for five major rivers in southern Italy (the Trigno, Biferno, Volturno, Sinni and Crati rivers) to support assessment of channel recovery and river restoration.Three distinct phases of channel adjustment are identified over the past 150years primarily driven by human disturbances. Firstly, slight channel widening dominated from the last decades of the nineteenth century to the 1950s. Secondly, from the 1950s to the end of the 1990s, altered sediment fluxes induced by in-channel mining and channel works brought about moderate to very intense incision (up to 6–7m) accompanied by strong channel narrowing (up to 96%) and changes in channel configuration from multi-threaded to single-threaded patterns. Thirdly, the period from around 2000 to 2015 has been characterized by channel stabilization and local widening. Evolutionary trajectories of the rivers studied are quite similar to those reconstructed for other Italian rivers, particularly regarding the second phase of channel adjustments and ongoing transitions towards channel recovery in some reaches. Analyses of river dynamics, recovery potential and connectivity with sediment sources of the study reaches, framed in their catchment context, can be used as part of a wider interdisciplinary approach that views effective river restoration alongside sustainable and risk-reduced river management.

The influence of wave action on coastal erosion along Monwabisi Beach, Cape Town

The coastline to the east of the Monwabisi Beach tidal pool has been subject to substantial visible coastal erosion. Monwabisi is located near the City of Cape Town and is situated along the northern coastline of False Bay. The erosion that has occurred has raised concern as it is damaging local infrastructure. The coastline retreat to the east of Monwabisi was investigated through analysis of aerial photographs and wave data to establish whether there is a relationship between dynamic wave action that this bay is subjected to, and the observed erosion within the study area. The maximum lateral coastal erosion at the Monwabisi study area from 2003 until 2014 was approximately 30m in a landward direction. Based on the correlation of the results between the rate of coastline retreat and the wave data, the study has concluded that the extreme rates of coastline retreat experienced within the study area at Monwabisi is most likely a direct result of a combination of influences including the number and height of big wave events, waves coming from a more southerly direction, the underlying geological substrate of the study area, and the impact that the local infrastructure has had on the geological substrate. Three time periods of maximum monthly erosion rates occurred from June 2008 to November 2009, March 2010 to March 2011 and April 2011 to June 2012.

Geomorphological impact and morphodynamic effects on flow conveyance of the 1999 jökulhlaup at sólheimajökull, Iceland

AbstractThe 1999 jökulhlaup at Sólheimajökull was the first major flood to be routed through the proglacial system in over 600 years. This study reconstructed the flood using hydrodynamic, sediment transport and morphodynamic numerical modelling informed by field surveys, aerial photograph and digital elevation model analysis. Total modelled sediment transport was 469 800 m3 (+/‐ 20%). Maximum erosion of 8.2 m occurred along the ice margin. Modelled net landscape change was –86 400 m3 (+/‐ 40%) resulting from –275 400 m3 (+/‐ 20%) proglacial erosion and 194 400 m3 (+/‐ 20%) proglacial deposition. Peak erosion rate and peak deposition rate were 650 m3 s‐1 (+/‐ 20%) and 595 m3 s‐1 (+/‐ 20%), respectively, and coincided with peak discharge of water at 1.5 h after flood initiation. The pattern of bed elevation change during the rising limb suggested widespread activation of the bed, whereas more organisation, perhaps primitive bedform development, occurred during the falling limb. Contrary to simplistic conceptual models, deposition occurred on the rising stage and erosion occurred on the falling limb. Comparison of the morphodynamic results with a hydrodynamic simulation illustrated effects of sediment transport and bed elevation change on flow conveyance. The morphodynamic model advanced flood arrival and peak discharge timings by 100% and 19%, respectively. However, peak flow depth and peak flow velocity were not significantly affected. We suggest that morphodynamic processes not only increase flow mass and momentum but that they also introduce a feedback process whereby flood conveyance becomes more efficient via erosion of minor bed protrusions and deposition that infills or subdues minor bed hollows. A major implication of this study is that reconstructions of outburst floods that ignore sediment transport, such as those used in interpretation of long‐term hydrological record and flood risk assessments, may need considerable refinement. Copyright © 2015 John Wiley & Sons, Ltd.

Changes in the distribution of indigenous forest in Table Mountain National Park during the 20th Century

Long-term changes in the distribution of Western Cape Afrotemperate Forest and Western Cape Milkwood Forest in Table Mountain National Park (TMNP) were examined using paired aerial and repeat ground-based photographs. All forest patches mapped on the aerial photographs taken in 1944 and 2008 were visited and boundaries between forest and adjacent vegetation types checked in the field. In addition, 50 historical ground-based photographs covering the period 1888 to 1980 were revisited between 2011 and 2012 and the change in forest cover was quantified using a 360 point sampling grid overlaid on each of the photograph pairs.Changes in fynbos, woody alien vegetation, alien grass, development and exposed rock and sand were also quantified. The analysis of aerial photographs showed that between 1944 and 2008 the number of forest patches on the Peninsula increased from 149 to 174 and total forest cover increased by 65.3% from 884.2ha to 1461.5ha. Only 13 of the forest patches decreased in cover after 1944 while 65 patches showed stasis and 96 increased in size. More than a third of the patches that decreased in size were of Western Cape Milkwood Forest located in proximity to expanding coastal development. The analysis of repeat ground-based photographs showed an increase in cover of Western Cape Afrotemperate Forest, alien grasses and urban development while fynbos vegetation, Western Cape Milkwood Forest, woody alien vegetation as well as exposed rock and sand decreased in cover. Historical land use practices such as firewood collection and a reduction in fire frequency relative to the fire regimes of the 19th century may also account for the changes observed in the historical photos. These results hold significance for the ecological management of TMNP in the face of changing climate and increased urbanisation.

Ecological assessment of morphological shore degradation at whole lake level aided by aerial photo analysis

Hydromorphological alterations of lake shores constitute an important pressure on Central European lakes. The local ecological effects of such alterations can be assessed by multimetric assessment methods based on eulittoral macroinvertebrate communities. However, such tools so far only enable a local assessment even if the European Union Water Framework (EU WFD) requires an assessment at whole-lake level. Since due to time and financial constraints it is not feasible to perform small-scale macroinvertebrate assessments over the whole length of the lake shore, the site-specific ecological assessment result needs to be extrapolated. In this study, we analyse the use of a physical habitat survey method including both ground surveys and aerial photo analysis (HML = HydroMorphology of Lakes survey protocol) to enable an extrapolation from local to whole lake ecological assessment. For that purpose, we correlated individual macroinvertebrate metrics as well as results of a multimetric macroinvertebrate-based index (I) with the areal cover of surrounding natural shore elements, (II) with the hydromorphological impact within an encircling rectangle around the macroinvertebrate sampling site, and (III) with the hydromorphological impact in the adjacent epi-, euand sublittoral subsegments. Building up on this, an ecological whole lake assessment was achieved by averaging multimetric index scores calculated for each subsegement based on a regression equation between the multimetric index and the hydromorphological impacts in the three subsegments. This whole lake assessment approach can most likely be applied to geographical regions outside Central Europe and lake types not analysed here (fluvial lowland lakes, prealpine/alpine lakes), but more studies are necessary to verify this. Eventually, the extrapolation presented here may complement existing lake assessments under the EU WFD solely focusing on water quality so far.

Changes of Marukh Glacier from 1945 to 2011

Field studies have been carried out in summer 2011 at Marukh Glacier located in western part of the Northern Caucasus. The studies included ground-based radio-echo sounding measurements at a frequency of 20 MHz and glacier surface elevation survey using a dual frequency differential GPS receiver. Changes of volume and surface area of the glacier for the period 1945–2011 have been estimated using aerial photo, satellite images and topographic maps analysis. It is founded that Marukh Glacier is retreating and has reduced its surface area by 17% for the past 66 years. Glacier volume is 0,276 km³ in 2011 and has decreased by 0,06 km³ since 1967.

Modern and ancient glaciation of northern slope of the Tavan-Bogdo-Ola massif

Dynamics of glaciation of the northern slope of Tavan-Bogdo-Ola in the period of 1962–2011 has been defined on basis of field observations and analysis of aerial photos. Glaciers of the first and of the second Late Neopleistocene glaciations, historical glacial stage and Little Ice Age (LIA) were reconstructed by geomorphologic methods. In 2009–2011 glaciation of the northern slope was represented by 12 glaciers with total area about 22 km². In the maximum of the first Late Neopleistocene glaciation the total area of the glaciers was 4 times larger than present, firn line depression was 620 m. In the maximum of the second glaciation it was 3 times larger than now, firn line depression was 460 m. In historical glacial stage the total area of glaciation was about 2 times larger than now, firn line depression was 170 m. In LIA the area of glaciation was 16 km² larger than now, the firn line was 125 m lower. From the maximum of the LIA till 1962 glaciers lost about 9,6 km² of its area, the level of firn line rose about 50 m. In 1962–2002 the loss of the glacial area was 3,2 km², in 2002–2009 – 3 km².

Earthquake triggered rock falls and their role in the development of a rock slope: The case of Skolis Mountain, Greece

Inventory of pre-earthquake and earthquake triggered landslides is used to provide insight into the interplay between climatic and tectonic forcing in the development of the rock slopes of the Skolis Mountain, in the NW Peloponnese. Aerial photograph analysis and surface mapping indicate that the Skolis Mountain is characterized by long-term climatically and tectonically controlled rock falls forming taluses. Temporally these taluses show a slow progressive inflation in surface area from 1945 to 2007. However, the post-earthquake surface area of the rock falls increased three times. Similarly 75 rock fall sites before the earthquake, increased into 89 after the Movri Mountain earthquake (Mw 6.4). In addition, during the earthquake a series of isolated rock falls descended Skolis slopes causing threat of the Santomerion village and blocking significant part of the dirt roads around it. These boulders are clustered in three areas beyond the base of taluses. The rock slope failures are controlled by a complex array of discontinuities that are conveniently related to rock mass classification following the geological strength index. These discontinuities are associated with joints and faults caused during the formation of the Hellenides fold- and thrust-belt, and/or related tectonic damage. We infer that a dense pattern of fractures in limestone plays a crucial role in the reactivation of movement within the rock falls during the 2008 Movri Mountain earthquake. All these data are used to define two borders, the taluses base and the rock fall hazard border beyond the base of taluses. For defining these borders we use the angle β drawn from the boulders' release zone down its maximal runout points. Our results indicate that the border defined by the β=33° corresponds to the climatically driven rock falls while the β=24° border is defined as the boulders' maximum runout during earthquakes.

Fluctuation of glaciers in the southeast Russian Altai and northwest Mongolia Mountains since the Little Ice Age maximum

The present state and dynamics (since the maximum of the LIA) of the glaciers of southeast Russian and north Mongolian Altai have been studied. Data were obtained from 15 areas of glaciation. The research is based on multiyear in situ observations and analysis of aerial photos of mid-1960s and high resolution space imagery; 553 modern glaciers with total area 313.4 km2 have been mapped and put down into catalogues, including glaciated areas and glaciers that have not been studied before. Glacial complexes with united accumulation zone and flat-summit glaciers in the center and valley glaciers on the sides are typical for the area of research. The firn line level rises from 3200–3300 m in the west to 3600–3700 m in the east. This tendency reflects the reduction of nourishment of the glaciers in this direction due to decrease of precipitation. The largest valley glaciers exist on the northeastern leeward slopes as a result of two to threefold concentration of snow. The last glacial advance in the maximum of LIA, according to dendrological data, finished in the first half of the 19th century. From the maximum of the LIA, the glaciation of the region lost about 51 %, ELA average uplift was 89 m. On the background of general trend of glacial retreat, there were several periods of stabilization of glacial fronts, the most distinct in mid-1960s. In the last 50 years, there were two warm and dry intervals: 1972–1981 and 1992–2008; and three cool and moist intervals: prior to 1972, during 1982–1994 and subsequent to 2009. It caused fluctuations of firn line altitude with about 300 m range and abrupt changes of glacial area. Maximal changes were observed between 1995 and 2008, when areas of the glaciers decreased with average rate 1–2 % year. Determination of retreat of glacial snouts after the LIA by geomorphic features is described by VI-phase scheme.