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Copyright of Avances is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At the research points, the relationship between the Normalized Difference Vegetation and Normalized Green Red Difference indices is characterized by a determination coefficient equal to 0.52. The estimation of the emission of carbon dioxide and nitrogen oxide in the forest air at an altitude of 40 m above the level of the soil cover during the growing season showed differences in their values during the daytime and at night. The results helped determine promising methods of inventory of the carbon landfill forest area for aboveground woody biomass assessment based on data obtained from several sources and land forest estimation research. The research involved: 1) integration of an unmanned aerial vehicle -based digital camera and lidar sensors in order to optimize the efficiency and cost of data collection; 2) taking advantage of high-resolution aerial photographs and sparse lidar point clouds using an information fusion approach and the ability to compensate for their shortcomings. [ABSTRACT FROM AUTHOR]

In this work, I determined the roughness conditions of the flood plain in an area of 523 ha in the southern part of Bodrogzug based on aerial photographs from 1965 and 2016. The inspiration for conducting the tests was the three recordings that were made of the area at the beginning and in the middle of the 20th century, and in the early 2000s. Based on the two previous recordings, the roughness of the area may have been much smaller than today due to the short grass pastures and the small amount of woody vegetation. To determine the roughness values, I used the categories developed by CHOW V. T. (1959) and NÉMETH E. (1959). The plant cover values recorded at the two times show significant differences. The proportion of very dense forests increased greatly, with the weighted roughness increasing by two and a half times in 2016 compared to 1965. This significantly reduces the speed of flood waters, which can lead to gradual siltation of the area. At the same time, the direction of landscape development is developing favourably, as the area's biodiversity is increasing. [ABSTRACT FROM AUTHOR]

The natural values of the fens and moorgrass meadows at Göd became known in the 1980s. The area of almost 70 hectares, previously used for centuries as pasture and meadow, has been isolated by urbanisation and land use has changed over the last three decades, with the ploughing up and conversion into a golf course and the designation of part of the valuable fen and Molinia meadows as nature reserves. These protected areas are well studied from a botanical point of view, even on a national scale, and the trends in vegetation change since the 1990s are therefore well understood. The aim of this article is to provide a historical overview of the landscape change in the fen and to explore the changes in flora and habitats. The research involved the analysis of historical maps and archival aerial photographs, the evaluation of flora lists from three botanical surveys carried out at 15-year intervals and a comparative analysis of habitat maps using GIS. The results show that the water regime of the studied wetlands is changing, the vegetation is degraded and becoming poorer in fen specialists, while at the same time the increase in habitat diversity has led to an enrichment of the fauna of the studied area. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study presents a method to generate historical orthomosaics using Structure-from-Motion (SfM) photogrammetry, historical aerial photographs, and lidar data, and then analyzes the horizontal accuracy and factors that can affect the quality of historical orthoimagery products made with these approaches. Two sets of historical aerial photographs (1934 and 1951) were analyzed, focused on the town of Woodstock in Connecticut, U.S.A. Ground control points (GCPs) for georeferencing were obtained by overlaying multiple data sets, including lidar elevation data and derivative hillshades, and recent orthoimagery. Root-Mean-Square Error values of check points (CPs) for 1934 and 1951 orthomosaics without extreme outliers are 0.83 m and 1.37 m, respectively. Results indicate that orthomosaics can be used for standard mapping and geographic information systems (GIS) work according to the ASPRS 1990 accuracy standard. In addition, results emphasize that three main factors can affect the horizontal accuracy of orthomosaics: (1) types of CPs, (2) the number of tied photos, and (3) terrain. [ABSTRACT FROM AUTHOR]

Copyright of Památky Archeologické is the property of Academy of Sciences of the Czech Republic, Institute of Archaeology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One consequence of global change causing widespread concern is the possibility of ecosystem conversions from one type to another. A classic example of this is vegetation type conversion (VTC) from native woody shrublands to invasive annual grasslands in the biodiversity hotspot of Southern California. Although the significance of this problem is well recognized, understanding where, how much, and why this change is occurring remains elusive owing to differences in results from studies conducted using different methods, spatial extents, and scales. Disagreement has arisen particularly over the relative importance of short‐interval fires in driving these changes. Chronosequence approaches that use space for time to estimate changes have produced different results than studies of changes at a site over time. Here we calculated the percentage woody and herbaceous cover across Southern California using air photos from ~1950 to 2019. We assessed the extent of woody cover change and the relative importance of fire history, topography, soil moisture, and distance to human infrastructure in explaining change across a hierarchy of spatial extents and regions. We found substantial net decline in woody cover and expansion of herbaceous vegetation across all regions, but the most dramatic changes occurred in the northern interior and southern coastal areas. Variables related to frequent, short‐interval fire were consistently top ranked as the explanation for shrub to grassland type conversion, but low soil moisture and topographic complexity were also strong correlates. Despite the consistent importance of fire, there was substantial geographical variation in the relative importance of drivers, and these differences resulted in different mapped predictions of VTC. This geographical variation is important to recognize for management decision‐making and, in addition to differences in methodological design, may also partly explain differences in previous study results. The overwhelming importance of short‐interval fire has management implications. It suggests that actions should be directed away from imposing fires to preventing fires. Prevention can be controlled through management actions that limit ignitions, fire spread, and the damage sustained in areas that do burn. This study also demonstrates significant potential for changing fire regimes to drive large‐scale, abrupt ecological change. [ABSTRACT FROM AUTHOR]

• The socio-cultural response to the morphological transformations of water regimes in peri -urban areas is investigated. • Land cover changes at the catchment level of a large river in Hong Kong from 1994 to 2022 are analyzed. • Mixed-methods research combining remote sensing (analysis of aerial and satellite photographs) and in-depth semi-structured interviews. • Integrating environmental mitigation strategies in channelization can moderate the negative impacts of engineering-driven fluvial morphological transformations, retaining place attachment and land care among local inhabitants. Rural-to-urban transformation in Southeast Asia must be discussed as a vicious cycle of hydrologic alteration, environmental degradation, and destructive land use changes that collectively jeopardize millions of lives. Particularly, top-down flood control schemes have been linked to significant degradation of the socioeconomic and biophysical features of rural landscapes and increasingly faster agricultural decline and environmental degradation. In recent years, growing awareness has focused on ecosystem fragility and the need for a water-sensitive approach in planning. Water management and stream renaturation are expanding and rapidly developing disciplines that have produced radical advancements in ecological, geomorphological, and hydrologic areas. Despite such progress, however, these disciplines have failed to offer major advancements in socially related fields. A paucity of scientific research exists on the association between hydrologic alteration and the transformation of the landscape—which is a socially constructed phenomenon. As a result, the socio-cultural response to the morphological transformations of water regimes in peri -urban and desakota areas remains under-investigated. The current study questions whether a specific morphological transformation of water streams, namely channelization cum environmental mitigation, can catalyze socio-cultural reactions and thus shape peculiar land use patterns. To examine that impact, we conducted a study on the Sheung Yue River in the New Territories of Hong Kong. Longitudinal data on the morphological change of the landscape at the catchment level from 1994 to 2022 were interpreted from aerial photographs and high-resolution satellite imagery, controlling for external factors. Alongside that data, 20 semi-structured interviews with local farmers provided in-depth knowledge of societal responses to the landscape mutation. Eleven interviews with knowledgeable informants also enhanced the understanding of river management and agricultural conservation. The overall findings revealed that integrating environmental mitigation strategies in channelization can moderate the negative impacts of the engineering-driven fluvial morphological transformation. Based on these findings, the study stresses the significance of socio-environmental responsive river management and integrated urban planning strategies for policymaking in Southeast Asia. [ABSTRACT FROM AUTHOR]

This study investigated how structural changes of a historical traditionally used forest landscape in Central Europe have affected traits of vegetation and wild bee communities. We compared the extent of gaps in the forest using aerial photographs between 1945 and 2020. And we found historic vegetation and bee surveys from 1975 and 1990, which we repeated in 2010 and 2020. We characterised the vegetation of the closed forest, the forest gaps and the small-scale meadows adjacent to the forest as well as the wild bee community by traits and investigated trait changes with Kruskal-Wallis tests. By NMDS we characterised sample plots and transect walks of timepoints with traits and species. Area of forest gaps decreased by 88% from 1945 to 2020 and by 74% from 1975 to 2020. In the traits of vegetation, Ellenberg Indicator Values (EIV) for moisture and soil nutrients significantly increased in closed forest, forest gaps and meadows adjacent to forest. The EIVs for light and temperature, and the number of red list species decreased. The number of wild bee species that specialise in visiting flowers with long tubes and hylophilic species declined. The number of eremophilic species, species with longer phenologies, and recently Red list species increased. In the NMDS figure of forest gaps and of adjacent meadows, different species and traits characterised more recent and older sample plots of vegetation and confirm the results of the Kruskal Wallis tests. Wild bee communities of 2010 and 2020 were characterised by frequent species, while those of 1975 and 1990 were not characterised by any species. The traits characterised the wild bee communities of the older and younger transect walks in accordance with the results of the Kruskal Wallis tests. In addition, oligolectic bees characterised the older transect walks. The loss of forest gaps represents a direct loss of habitat for many plant and wild bee species. In addition, the qualitative changes in vegetation indicate a deterioration in habitat quality for plants of open forests and wild bees. Among wild bees, specialists were negatively affected by the changes described. These developments were reflected in the initial downward trend in Red List bee species. The increase in bee species with longer phenology, in eremophilic species, the decrease in hylophilic species, and the recent increase in red-listed species can indicate climate change. Therefore, this study underlines the importance of the preservation and development of ecologically valuable forest gaps, particularly in historical traditionally used forests with a typical species composition. [Display omitted] • loss of 88% in forest gaps from 1945 to 2020. • increase in EIV for nitrogen and moisture of vegetation from 1975 to 2020. • decrease in EIV for light, for temperature and Red List species of vegetation. • decline in specialised and hylophilic wild bee species from 1975 to 2020. • increase in eremophilic wild bee species and species with a longer phenology. [ABSTRACT FROM AUTHOR]

Copyright of Bitácora Urbano/Territorial is the property of Bitacora Urbano/Territorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ager: Journal of Depopulation & Rural Development Studies / Revista de Estudios sobre Despoblación y Desarrollo Rural is the property of Rolde de Estudios Aragoneses and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Our understanding of tundra fire effects in Northern Alaska is limited because fires have been relatively rare. We sampled a 70+ year-old burn visible in a 1948 aerial photograph for vegetation composition and structure, soil attributes, terrain rugosity, and thermokarst pit density. Between 1948 and 2017 the burn initially became wetter as ice wedges melted but then drained and dried as the troughs became hydrologically connected. The reference tundra has become wetter over the last few decades and appears to be lagging through a similar sequence. The burn averaged 2.5 °C warmer than the reference tundra at 30 cm depth. Thinning of organic soil following fire appears to dramatically accelerate the background degradation of ground-ice features in response to climate change and promotes a plant community that is distinct in terms of taxa and structure, dominated by tall willows and other competitive, rather than cold-tolerant, species. The cover of sedges and mosses is low while that of willows and grass is high relative to the reference tundra. The changes in plant community composition and structure, increasing ground temperature, and thermokarst lead us to expect the observed biophysical changes to the tundra will persist centuries into the future. • An old tundra burn was found in a 1948 aerial photograph in northern Alaska. • Fire resulted in melted ground-ice, thermokarst, and conspicuously tall willows. • The adjacent unburned tundra also shows signs of thermokarst related to climate change. • There was a shift from cold-tolerant to competitive plants within the burn. • Ground temperature continues to warm relative to the unburned tundra. [ABSTRACT FROM AUTHOR]

Most North American Eared Grebes (Podiceps nigricollis) undertake a post-breeding migration to two hypersaline lakes in the USA: Mono Lake in California and Great Salt Lake in Utah. Single air photo surveys were conducted in mid-October at Mono Lake from 1996-2012 and multiple fall surveys were conducted from 2013-2018, the latter to determine variation in abundance patterns within and across years. In four of the six years with multiple fall surveys, peak abundance occurred in mid-October as expected. However, in 2014 and 2015, Eared Grebe numbers declined dramatically soon after arrival, coinciding with low levels of their primary food, brine shrimp (Artemia monica). Abundance remained low from 2016-2018, and this could have been due to a shift to Great Salt Lake or to a massive mortality event. In 2017 and 2018, Eared Grebes breeding in south-central British Columbia, Canada were marked with Very High Frequency (VHF) radio transmitters and light-level geolocator (GLS) tags. Contrary to 1996, when the majority of VHF-tagged birds were molting/staging on Mono Lake, our 2017-2018 telemetry data indicated that most individuals were on Great Salt Lake. Our study provides insight into the variable abundance patterns at Mono Lake and novel information on Eared Grebe migration patterns. [ABSTRACT FROM AUTHOR]

Questions surrounding the emergence of highly mobile nomadic pastoralism and the origins of the associated Scythian material culture have a long history in Eurasian steppe archaeology, but advances in knowledge have been hindered by a lack of data. Here we present new findings on the Early Iron Age royal burial mound Tunnug 1 in Tuva. While the site belongs to the same cultural tradition as Arzhan 1, the conceptual roots of the funerary ritual architecture can be traced to precursors in the Mongun Taiga culture and the Mongolian deer stone khirigsuur complex. The clay architecture uncovered at Tunnug 1 does not find any regional comparisons and possibly hints towards a western Central Asian contribution to the formation of the earliest Scythian horizon. Our research demonstrates the value of a multi-disciplinary approach to documenting monumental earthen architecture, including technical approaches (satellite imagery, aerial photographs, 3D models, digital elevation models, geophysics, and radiocarbon dating) with an analysis of construction material and associated finds. [ABSTRACT FROM AUTHOR]

Copyright of Listy Cukrovarnicke a Reparske is the property of VUC Praha a.s. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Otofuke River is a tributary of the Tokachi River, Hokkaido Japan, consisting of a channelized reach with a steep slope and a relatively large designed width. In August 2016, the river witnessed four major flooding events with a record-breaking discharge within a time span of 15 days. The Otofuke River originally had a straight channelized reach. However, because of a series of flooding events, the river promptly followed a sinusoidal path, damaging the riverbank embankments. The straight channelized reach of Otofuke River faced active erosion of both banks, leading to the formation of a meandering channel planform. This also led to levee breaches at the seven locations. In order to understand the mechanism of such a quick shift in river channel planform, we collected various field survey data and conducted computational analysis. We investigated the underlying processes by capturing the complex interactions between the rapid channel migration, unsteady discharge, and sediment transport. Field surveys including aerial photographs and images showed rapid formation of a meandering planform in the Otofuke River as a result of the typhoon on 31 August 2016. According to the maximum water level traces, bank erosion developed after the peak discharge. Numerical investigation revealed that alternate sandbars continuously developed and propagated downstream until the moment of peak discharge, and a significant accumulation of sediment subsequently started on the bars at the mid-channel during the flood falling stage. Such morphological processes led to strong flow deflections transversely toward the embankment that resulted in lateral channel shifting and levee breaches at a location where vegetation along the embankments had already disappeared. [ABSTRACT FROM AUTHOR]

Copyright of Boletim de Geografia is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A riparian vegetation dynamics model was proposed to consider the mutual influence of hydro-morphology and vegetation dynamics in a sand-bed river. The simulation model consists of four sub-models: river flow and sediment transport, recruitment, growth and expansion, and destruction of vegetation. The numerical simulation was applied to the downstream part of a sand-bed river for predicting the vegetation dynamics over a long period. The model performance is validated by comparison with the field investigation results obtained from analysis of aerial photographs. The simulation results showed that the growth of vegetation starts from the shoreline and the downstream part of sandbars, and the riparian vegetation increases the stability and the relative elevation of the bars. From the good agreements of the temporal tendencies of vegetation recruitment, expansion, and destruction with those obtained from the aerial photographs analysis, the vegetation dynamics model proposed in this study was verified to reproduce the long-term trend of riparian vegetation dynamics fairly well. Finally, the model was applied to different sandbar modes, i.e., alternating bars and multiple bars. The simulation results indicated that the expansion and destruction rates of vegetation show similar tendencies for both bar mode cases, and they were mainly determined by the magnitude of the annual maximum flood. However, the amount of vegetation coverage rate in the alternating bar case was higher than that in the multiple bar case. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Late prehistoric and early historic communal hunting sites along the southwestern mountainous margins of the Great Basin, United Sates, include timber-built corral-traps estimated to be only a few hundred years old. In most of these, no animal bones or direct evidence for the targeted species were found in the corrals. Our goals were to characterize and reconstruct past use of these sites, and we chose two distinct case studies, Anchorite Pass and Excelsior. We provide high-resolution documentation of the sites and their archaeological components, using nearly 10,000 aerial photographs as the basis for 3D modeling. We specifically address construction characteristics which include the incorporation of living trees and felling juniper timbers by fire. Drawing on limited ethnographic sources and current seasonal routes of local mule deer herds, we suggest the two sites were used for seasonal trapping of such herds. Forest fires and modern construction severely endanger such vulnerable sites. [ABSTRACT FROM AUTHOR]

The paper deals with the impact of sugar industry, as the key landscape innovation in the second half of the 19th century, on the change in the use of land of Moravian floodplains in the Podyjí Region and Haná Region (using the example of the surroundings of sugar mill pairs in Hrušovany nad Jevišovkou and Pohořelice, Brodek u Přerova and Prosenice). Each pair of areas represents the vicinity of nearby sugar mills, one of which is currently in operation, while the other has already completed its activities. The process of rebuilding the use of riverine plains in the neighbourhood of sugar mills was studied using publicly available data -- (1) the maps of the Second Austrian Military Survey from the years 1836 -- 1840 (regading the period before the sugar mills were founded), (2) the maps of the Third Austrian Military Survey reambulled between 1919 -- 1937 (regarding the period after the sugar mills were founded) and (3) the present state captured in current aerial photographs (2016 and 2017). All geostatistical data processing was carried out in the ArcGIS v. 10.5 and Microsoft Excel 2010. There, a tenfold decrease in riverine meadows was identified before and after the construction of the sugar mills and after their disappearance, the area of the meadows did not recover at all. [ABSTRACT FROM AUTHOR]