Journal articles: 'Water Aerial photography in hydrology'

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Fankhauser, R. "Automatic determination of imperviousness in urban areas from digital orthophotos." Water Science and Technology 39, no. 9 (May 1, 1999): 81–86. http://dx.doi.org/10.2166/wst.1999.0447.

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Determination of impervious areas in urban regions is the most labour-intensive part of data acquisition for rainfall-runoff modelling in urban hydrology. This paper presents an automatic determination method of imperviousness from aerial photographs. The colour, CIR (colour infrared) aerial photographs and orthophotos used have a ground resolution of 25 to 75 centimetres. A maximum likelihood classification algorithm was applied to assign each pixel to a surface category. Classification results were then then overlaid with the subcatchments to determine the imperviousness of each subcatchment. Classification and overlay were carried out with the raster-based GIS IDRISI. The method was tested on various catchment areas, and the results compared with data obtained from manually digitised surfaces. Accuracy of the estimated imperviousness for the entire catchment areas was within 10 %. The deviations for individual subcatchments were much higher. Equivalent results were obtained for colour and CIR photograplhs. A combination of both spectral ranges resulted only in a slight improvement. Consequently, this does not justify the additional costs of the second image. The developed method is an interesting alternative for use on large catchment areas where manual digitisation is very time-consuming and, thus, expensive.

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Ahring, T. S., and D. R. Steward. "Groundwater surface water interactions and the role of phreatophytes in identifying recharge zones." Hydrology and Earth System Sciences 16, no. 11 (November 9, 2012): 4133–42. http://dx.doi.org/10.5194/hess-16-4133-2012.

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Abstract. Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with pre-development and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50%) in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photography is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

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Ahring, T. S., and D. R. Steward. "Groundwater surface water interactions through streambeds and the role of phreatophytes in identifying important recharge zones." Hydrology and Earth System Sciences Discussions 9, no. 6 (June 14, 2012): 7613–38. http://dx.doi.org/10.5194/hessd-9-7613-2012.

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Abstract. Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with predevelopment and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50%) in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photophaphy is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

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Díaz de León-Guerrero, Samantha, Rodrigo Méndez-Alonzo, Stephen H. Bullock, and Enrique R. Vivoni. "Hydrological and topographic determinants of biomass and species richness in a Mediterranean-climate shrubland." PLOS ONE 16, no. 5 (May 27, 2021): e0252154. http://dx.doi.org/10.1371/journal.pone.0252154.

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Background In arid and semiarid shrublands, water availability directly influences ecosystem properties. However, few empirical tests have determined the association between particular soil and hydrology traits with biodiversity and ecosystem biomass at the local scale. Methods We tested if plant species richness (S) and aboveground biomass (AGB) were associated with soil and topographic properties on 36 plots (ca. 12.5 m2) in 17 hectares of chaparral in the Mediterranean-climate of Valle de Guadalupe, Baja California, México. We used close-to-the-ground aerial photography to quantify sky-view cover per species, including all growth forms. We derived an elevation model (5 cm) from other aerial imagery. We estimated six soil properties (soil water potential, organic matter content, water content, pH, total dissolved solids concentration, and texture) and four landscape metrics (slope, aspect, elevation, and topographic index) for the 36 plots. We quantified the biomass of stems, leaves, and reproductive structures, per species. Results 86% of AGB was in stems, while non-woody species represented 0.7% of AGB but comprised 38% of S (29 species). Aboveground biomass and species richness were unrelated across the landscape. S was correlated with aspect and elevation (R = 0.53, aspect P = 0.035, elevation P = 0.05), while AGB (0.006–9.17 Kg m-2) increased with soil water potential and clay content (R = 0.51, P = 0.02, and P = 0.04). Only three species (11% of total S) occupied 65% of the total plant cover, and the remaining 26 represented only 35%. Cover was negatively correlated with S (R = -0.38, P = 0.02). 75% of AGB was concentrated in 30% of the 36 plots, and 96% of AGB corresponded to only 20% of 29 species. Discussion At the scale of small plots in our studied Mediterranean-climate shrubland in Baja California, AGB was most affected by soil water storage. AGB and cover were dominated by a few species, and only cover was negatively related to S. S was comprised mostly by uncommon species and tended to increase as plant cover decreased.

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Stefouli, M., and P. Tsombos. "IDENTIFICATION AND MONITORING OF FRESH WATER OUTFLOWS IN COASTAL AREAS: PILOT STUDY ON PSAHNA AREA / EVIA ISLAND - GREECE." Bulletin of the Geological Society of Greece 36, no. 2 (July 23, 2018): 928. http://dx.doi.org/10.12681/bgsg.16894.

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Earth systems are interrelated in complex ways, which are inadequately understood. An improved understanding of these systems is necessary in order to develop effective policies for hydrologie management. Furthermore, the results should be communicated to decision-makers. The aim of the work has been to evaluate the applicability of the use of digital multi-temporal Landsat 5 / 7 images and aerial photography, for the mapping of local scale fresh water outflows, geological features and monitoring changes of the water outflows in coastal areas. "Psahna" map sheet (HAGS, 1977) in the Central part of Evia island in Greece has been used as pilot project area of study. Processing techniques have been applied for the: • Application of integrated image processing / GIS vector data techniques. • Image integration and creation of data fusion image products. • Automatic raster to vector conversion techniques, for the identification of the areal extent of changes in conditions of the water outflows through time and final map updating. The contribution of the remotely sensed data to the geologic / géomorphologie mapping and identification of changes of fresh water outflow through time is indicated with the processed satellite imagery for the pilot project area. Generally, the use of the remotely sensed images in map updating lies in the fact, that various hydrologie and geologic features can be mapped quickly for large areas while any temporal changes can be identified and evaluated. The satellite data seem to be a cost-effective solution for the map updating procedure. The cost to processing functions is well justifiable to a geologic / hydro-geologic-hydrologic map updating procedure. The system provides monitoring and feedback at appropriate spatial scales, using high resolution satellite remote sensing data and state of the art GIS techniques.

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Zogg, Gregory P., and Burton V. Barnes. "Ecological classification and analysis of wetland ecosystems, northern Lower Michigan, U.S.A." Canadian Journal of Forest Research 25, no. 11 (November 1, 1995): 1865–75. http://dx.doi.org/10.1139/x95-201.

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We describe an ecological, multifactor approach to wetland classification in which ecosystem types are identified on the basis of the simultaneous integration of physiography, climate, hydrology, soil, and vegetation. Aerial photographs and field reconnaissance were used to characterize the diversity of wetlands of the 4000-ha University of Michigan Biological Station, northern Lower Michigan. Twenty-eight wetland units, including nutrient-rich swamps, ombrotrophic bogs, and many intermediate types, were identified. Eight wetland ecosystems, composing 79% of the total wetland area, were sampled extensively and classified primarily on the basis of the major glacial landforms and physiographic features of the region. Canonical variates analysis was used to evaluate the distinctness of these physiographically determined units in relation to various biotic and abiotic variables. Wetland types were poorly discriminated by canonical variates analysis of overstory composition data; better separation among types was achieved using ground-flora vegetation, hydrology, or soil characteristics. To demonstrate the utility of the multifactor approach to applications in wetland ecology, vegetation–environment relationships were examined using canonical correspondence analysis. Patterns of ground-flora community composition across all ecosystems were related to substrate characteristics, primarily organic matter composition, in addition to water chemistry and light. The results suggest that a multifactor approach, within a landscape framework, is useful in distinguishing wetlands at local scales, particularly where differences in overstory vegetation among ecosystems tend to be masked by human-caused disturbance. However, the landform-mediated differences in various wetland characteristics that we observed argue for a consideration of landscape-level physiography in classification and management even at broader scales.

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Remmel, Tarmo K., Kenton W. Todd, and James Buttle. "A comparison of existing surficial hydrological data layers in a low-relief forested Ontario landscape with those derived from a LiDAR DEM." Forestry Chronicle 84, no. 6 (December 1, 2008): 850–65. http://dx.doi.org/10.5558/tfc84850-6.

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The current provincial-extent digital elevation model (DEM) and corresponding hydrological maps for Ontario have been produced using traditional photogrammetry and aerial photograph interpretation. This process is labour-intensive and requires visual interpretation of stereo image pairs. The ground surface and small hydrological features may be inaccurately delineated in areas where vegetation is dense or the ground is otherwise shielded from aerial view. In an effort to improve and automate delineation of hydrological features, we examined the behaviour and final products of the D8 flowrouting algorithm in 2 software environments (TAS and TauDEM for ArcGIS) operating on a high spatial resolution DEM derived using canopy-penetrating light detection and ranging (LiDAR) technology in a pilot study in the Romeo Malette Forest (41.25°N, 81.50°W). Filtered LiDAR data points (5-m spacing) were interpolated using IDW, TIN, and splines, each resulting in a 2.5-m spatial resolution DEM. Results demonstrate improved realism in the characterization of surficial hydrology by LIDAR derived products as compared to applying identical algorithms on existing coarser provincial data. Benefits include the ability to represent streams of lower Strahler order to define crisp watershed boundaries, and the more accurate identification of local depressions that form potentially wet sites. This approach identifies wet sites that should be avoided during forest operations (e.g., skidder traffic) and can provide additional information for trail layout, road planning, and water crossings. By increasing the number of uses of LiDAR, the capital investment in these data becomes increasingly palatable for forest companies interested in obtaining detailed plans of their forest holdings. Key words: LiDAR, DEM, OBM, spatial resolution, interpolation, Strahler stream order, flow routing, topographic wetness

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Magolan, Jessica Lynn, and Joanne Nancie Halls. "A Multi-Decadal Investigation of Tidal Creek Wetland Changes, Water Level Rise, and Ghost Forests." Remote Sensing 12, no. 7 (April 3, 2020): 1141. http://dx.doi.org/10.3390/rs12071141.

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Coastal wetlands play a vital role in protecting coastlines, which makes the loss of forested and emergent wetlands devastating for vulnerable coastal communities. Tidal creeks are relatively small hydrologic areas that feed into larger estuaries, are on the front lines of the interface between saltwater and freshwater ecosystems, and are potentially the first areas to experience changes in sea level. The goal of this study was to investigate wetland changes through time at two tidal creeks (Smith Creek and Town Creek) of the Cape Fear River estuary in southeastern North Carolina, USA, to determine if there is a spatial relationship between habitat change, physical geography characteristics, and the rate of wetland migration upstream. Historic aerial photography and recent satellite imagery were used to map land cover and compute change through time and were compared with derived physical geography metrics (sinuosity, creek width, floodplain width, floodplain elevation, and creek slope). The primary results were: (1) there was a net gain in emergent wetlands even accounting for the area of wetlands that became water, (2) wetlands have migrated upstream at an increasing rate through time, (3) land cover change was significantly different between the two creeks (P = 0.01) where 14% (67.5 ha) of Smith Creek and 18% (272.3 ha) of Town Creek transitioned from forest to emergent wetland, and (4) the transition from emergent wetland to water was significantly related to average change in creek width, floodplain elevation, and average water level. In conclusion, this research correlated habitat change with rising water level and identified similarities and differences between neighboring tidal creeks. Future research could apply the methodologies developed here to other coastal locations to further explore the relationships between tides, sea level, land cover change, and physical geography characteristics.

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Pavlov, V. I. "Aerial photography of the water area." Geodesy and Cartography 956, no. 2 (March 20, 2020): 18–24. http://dx.doi.org/10.22389/0016-7126-2020-956-2-18-24.

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During the development of water resources the characteristics of excitement, direction, and flow velocity, depth, points of bottom, temperature and chemical composition of water is to be taken into account. Some of these indicators are determined through the results of measuring single aerial photographs and their stereoscopic pairs. Making aerial photography (APS) of water surface on technology for topographic land survey enables obtaining only single overlapping aerial photographs, as the water surface is in constant motion. Stereoscopic pairs of aerial photographs can be obtained if photographing is performed simultaneously by two aerial cameras (AFA) with close elements of internal orientation. The author considers two technological schemes of using two AFA in aerial photography of water space

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Eyton, J. Ronald. "Student Aerial Photography." Geocarto International 20, no. 4 (December 2005): 65–73. http://dx.doi.org/10.1080/10106040508542366.

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Grama, Vasile, and Andrei Iacovlev. "GEODESY, CARTOGRAPHY AND AERIAL PHOTOGRAPHY." GEODESY, CARTOGRAPHY AND AERIAL PHOTOGRAPHY 92,2020, no. 92 (December 24, 2020): 37–44. http://dx.doi.org/10.23939/istcgcap2020.92.037.

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Abstract. The goal of this research is the assessing of the current conditions of water protection strips in their role as an effective buffer that prevents water bodies from deteriorating due to soil erosion and pollution. In base of this study the action plan is developing to improve the conditions of the water protection strips for the lakes. The approach focused on the idea of an empirical study (based on observations and field measurements) on the environmental quality. Is proposed an integral analysis of the territory of the protection strips, the processes and phenomena taking place within them, in order to obtain a clear picture of the state of the environment. In the scope to administrate, and to assure the visualization and transparency of this study the project blog on the "blogspot.com" platform was created with properly configured geographic interest patterns. Cartographic data were published on Google Maps and integrated in blog. Thus, by accessing the blog, the views of the lake, the points of interest, with the necessary attributes is accessing with the possibility for the spatial analyses. The preliminary results show the positive effects and high interest of the stakeholders concerning of WebGIS technology for the assessment of environmental conditions of water protection strips along the Costesti- Stinca reservoirs. Scientific novelty consists in the optimal combination of the blogspot application on the google maps by integration of spatial data with different software (QGIS, Mapinfo, ArcGIS) and geospatial database - PostGIS. Easy to publish, to visualization and monitoring. The practical significance is expressed by objective reflection of a type of activity that takes place in space, including environmental phenomena, vizualisation and monitoring of them.

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Moore, E. "Water Management in Early Cambodia: Evidence from Aerial Photography." Geographical Journal 155, no. 2 (July 1989): 204. http://dx.doi.org/10.2307/635062.

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Protsyk, Mykhailo, Borys Chetverikov, and Andrii Ivanevych. "GEODESY, CARTOGRAPHY, AND AERIAL PHOTOGRAPHY." GEODESY, CARTOGRAPHY, AND AERIAL PHOTOGRAPHY 93,2021, no. 93 (June 23, 2021): 72–84. http://dx.doi.org/10.23939/istcgcap2021.93.072.

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Aim of the work. To develop a method of automated allocation of catchment basins and obtaining their hydrological and morphometric characteristics, which is based on digital terrain models. Methods and results of work. A necessary condition for the correct filling of the terrain is the presence of points of true flow at the edge of the settlement area (if the river flows into the lake, it should not enter the calculated area completely, otherwise incorrect results will be obtained). By performing the operation of filling the relief of the terrain, a new dem is created, which does not contain fictitious depressions and is used in the next step as input data to calculate the flow direction according to the algorithm d8. According to the proposed technological scheme it is necessary to process step by step the following six blocks: filling of closed depressions, calculation of runoff direction, calculation of total runoff, creation of point vector data set of closing points (mouth points), creation of watershed boundaries, raster-vector data conversion. Theoretical research tested the method of automated allocation of watersheds, namely the determination of hydrological and morphometric parameters of the terrain. The pools were ranked according to these parameters according to the existing classifications, a series of relevant thematic electronic maps was compiled. It should be noted that in Skole district of lviv region there are 590 catchment areas, and their area is 1407 km2. Watersheds are classified by outcrop, namely low-mountain basins in the region of 6, their area is 7 km2, medium-mountain 360, area 755 km2, high-mountain 224, area 645 km2. Pools are classified according to the average slope: the first category from 0-3 degrees, very gentle slopes - pools 27, area 7 km2; the second category from 9-12 degrees, sloping slopes-pools of 128, the area 303 km2; the third category from 12-15> degrees, steep slopes - pools of 225, the area 648 km2. The accuracy between the reference and the original relief model was evaluated. We can say that sle = 0.63 (m) slope, sle = 5.43 (m) height. Scientific novelty and practical significance. The technological scheme of automated separation of catchment basins according to digital relief models for Skoliv district of lviv region is proposed and the method of separation of catchment basins is worked out. According to the developed method, maps of watercourses of different orders and their catchment basins and classification of basins by area on the territory of Skole administrative district, which can be used by local organizations on water resources, are constructed.

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Birkbeck, A. E., and G. F. Tomlins. "Aerial Photography for the Detection of Leachate Migration from Landfills." Water Quality Research Journal 20, no. 3 (August 1, 1985): 92–102. http://dx.doi.org/10.2166/wqrj.1985.030.

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Abstract Aerial photography of the perimeters of two landfilled areas in British Columbia was acquired in colour and infrared emulsions. The photography was examined for evidence of leakage, or flooding of the leachate collection ditches surrounding the landfill and vegetation stress caused by the landfilling. At. one site the photography was acquired using a miniature experimental remotely piloted aircraft. This aircraft carries two gimbal-mounted 35 mm cameras which allow simultaneous vertical photography using two different film emulsions, different lenses, and/or filter combinations. At the second landfill site, oblique aerial photography was acquired from a Cessna 172 aircraft. Preliminary interpretation of the photography was followed by visits to locations where possible problems associated with leachate containment were apparent. The results indicated several locations where leachate was not fully contained by the ditch network and some areas of vegetation stress. Further studies at the second site confirmed that improved containment was effective in preventing further environmental damage.

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Walstra, J., J. H. Chandler, N. Dixon, and T. A. Dijkstra. "Aerial photography and digital photogrammetry for landslide monitoring." Geological Society, London, Special Publications 283, no. 1 (2007): 53–63. http://dx.doi.org/10.1144/sp283.5.

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Vélez-Nicolás, Mercedes, Santiago García-López, Luis Barbero, Verónica Ruiz-Ortiz, and Ángel Sánchez-Bellón. "Applications of Unmanned Aerial Systems (UASs) in Hydrology: A Review." Remote Sensing 13, no. 7 (April 1, 2021): 1359. http://dx.doi.org/10.3390/rs13071359.

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In less than two decades, UASs (unmanned aerial systems) have revolutionized the field of hydrology, bridging the gap between traditional satellite observations and ground-based measurements and allowing the limitations of manned aircraft to be overcome. With unparalleled spatial and temporal resolutions and product-tailoring possibilities, UAS are contributing to the acquisition of large volumes of data on water bodies, submerged parameters and their interactions in different hydrological contexts and in inaccessible or hazardous locations. This paper provides a comprehensive review of 122 works on the applications of UASs in surface water and groundwater research with a purpose-oriented approach. Concretely, the review addresses: (i) the current applications of UAS in surface and groundwater studies, (ii) the type of platforms and sensors mainly used in these tasks, (iii) types of products generated from UAS-borne data, (iv) the associated advantages and limitations, and (v) knowledge gaps and future prospects of UASs application in hydrology. The first aim of this review is to serve as a reference or introductory document for all researchers and water managers who are interested in embracing this novel technology. The second aim is to unify in a single document all the possibilities, potential approaches and results obtained by different authors through the implementation of UASs.

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Gal, Laetitia, Manuela Grippa, Pierre Hiernaux, Léa Pons, and Laurent Kergoat. "The paradoxical evolution of runoff in the pastoral Sahel: analysis of the hydrological changes over the Agoufou watershed (Mali) using the KINEROS-2 model." Hydrology and Earth System Sciences 21, no. 9 (September 13, 2017): 4591–613. http://dx.doi.org/10.5194/hess-21-4591-2017.

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Abstract. In recent decades, the Sahel has witnessed a paradoxical increase in surface water despite a general precipitation decline. This phenomenon, commonly referred to as the Sahelian paradox, is not completely understood yet. The role of cropland expansion due to the increasing food demand by a growing population has been often put forward to explain this situation for the cultivated Sahel. However, this hypothesis does not hold in pastoral areas where the same phenomenon is observed. Several other processes, such as the degradation of natural vegetation following the major droughts of the 1970s and the 1980s, the development of crusted topsoils, the intensification of the rainfall regime and the development of the drainage network, have been suggested to account for this situation. In this paper, a modeling approach is proposed to explore, quantify and rank different processes that could be at play in pastoral Sahel. The kinematic runoff and erosion model (KINEROS-2) is applied to the Agoufou watershed (245 km2), in the Gourma region in Mali, which underwent a significant increase of surface runoff during the last 60 years. Two periods are simulated, the past case (1960–1975) preceding the Sahelian drought and the present case (2000–2015). Surface hydrology and land cover characteristics for these two periods are derived by the analysis of aerial photographs, available in 1956, and high-resolution remote sensing images in 2011. The major changes identified are (1) a partial crusting of isolated dunes, (2) an increase of drainage network density, (3) a marked decrease in vegetation with the nonrecovery of tiger bush and vegetation growing on shallow sandy soils, and (4) important changes in soil properties with the apparition of impervious soils instead of shallow sandy soil. The KINEROS-2 model was parameterized to simulate these changes in combination or independently. The results obtained by this model display a significant increase in annual discharge between the past and the present case (p value < 0.001), which is consistent with observations, despite a slight overestimation of the past discharge. Mean annual discharges are estimated at 0.51 × 106 m3 (2.1 mm yr−1) and 3.29 × 106 m3 (13.4 mm yr−1) for past and present, respectively. Changes in soil properties and vegetation cover (tiger bush thickets and grassland on shallow sandy soil) are found to be the main factors causing this increase of simulated runoff, with the drainage network development contributing to a lesser extent but with a positive feedback. These results shed a new light on the Sahelian paradox phenomenon in the absence of land use change and call for further tests in other areas and/or with other models. The synergetic processes highlighted here could play a role in other Sahelian watersheds where runoff increase has been also observed.

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Booth, D. Terrance, and Samuel E. Cox. "Very Large Scale Aerial Photography for Rangeland Monitoring." Geocarto International 21, no. 3 (September 2006): 27–34. http://dx.doi.org/10.1080/10106040608542390.

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Kerner, S., I. Kaufman, and Y. Raizman. "ROLE OF TIE-POINTS DISTRIBUTION IN AERIAL PHOTOGRAPHY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-3/W4 (March 17, 2016): 41–44. http://dx.doi.org/10.5194/isprsarchives-xl-3-w4-41-2016.

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Automatic image matching algorithms, and especially feature-based methods, profoundly changed our understanding and requirements of tie points. The number of tie points has increased by orders of magnitude, yet the notions of accuracy and reliability of tie points remain equally important. The spatial distribution of tie points is less predictable, and is subject only to limited control. Feature-based methods also highlighted a conceptual division of the matching process into two separate stages – feature extraction and feature matching. In this paper we discuss whether spatial distribution requirements, such as Von Gruber positions, are still relevant to modern matching methods. We argue that forcing such patterns might no longer be required in the feature extraction stage. However, we claim spatial distribution is important in the feature matching stage. We will focus on terrains that are notorious for difficult matching, such as water bodies, with real data obtained by users of VisionMap’s A3 Edge camera and LightSpeed photogrammetric suite.

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Kerner, S., I. Kaufman, and Y. Raizman. "ROLE OF TIE-POINTS DISTRIBUTION IN AERIAL PHOTOGRAPHY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-3/W4 (March 17, 2016): 41–44. http://dx.doi.org/10.5194/isprs-archives-xl-3-w4-41-2016.

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Automatic image matching algorithms, and especially feature-based methods, profoundly changed our understanding and requirements of tie points. The number of tie points has increased by orders of magnitude, yet the notions of accuracy and reliability of tie points remain equally important. The spatial distribution of tie points is less predictable, and is subject only to limited control. Feature-based methods also highlighted a conceptual division of the matching process into two separate stages – feature extraction and feature matching. In this paper we discuss whether spatial distribution requirements, such as Von Gruber positions, are still relevant to modern matching methods. We argue that forcing such patterns might no longer be required in the feature extraction stage. However, we claim spatial distribution is important in the feature matching stage. We will focus on terrains that are notorious for difficult matching, such as water bodies, with real data obtained by users of VisionMap’s A3 Edge camera and LightSpeed photogrammetric suite.

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Werth, Lee F., and Edgar A. Work. "Applications of large‐scale aerial photography for rangeland monitoring." Geocarto International 7, no. 1 (March 1992): 11–18. http://dx.doi.org/10.1080/10106049209354347.

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Andreassen, Liss Marie, Hallgeir Elvehøy, and Bjarne Kjøllmoen. "Using aerial photography to study glacier changes in Norway." Annals of Glaciology 34 (2002): 343–48. http://dx.doi.org/10.3189/172756402781817626.

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AbstractThe Norwegian Water Resources and Energy Administration has photographed glacial areas in Norway for several decades. Detailed maps or digital terrain models have been made for selected glaciers from vertical aerial photographs. Multiple models of seven glaciers have been used here to calculate glacier volume change during the time between mappings using the geodetic method. Analyses and results are presented and compared with traditional mass-balance measurements. We estimated uncertainties of ±1.3–2.7mw.e. for the geodetic method, and ±1.3 –3.5mw.e. for the traditional method. The discrepancies between the methods varied between 0.4 and 4.7 mw.e. All glaciers decreased in volume from the 1960s/70s to the 1990s, except Hardangerjøkulen. This glacier experienced a significant increase in volume: the geodetic and traditional methods showed net balance values of +6.8m and +9.4mw.e., respectively. Trollbergdalsbreen had the largest total volume loss: the geodetic and traditional methods showed net balance values of –12.3 and –16.8mw.e.

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Zvyagin, K. N., and D. D. Maltsev. "Revisiting the digital noise reduction in automatic contouring of “ice-water” objects." Arctic and Antarctic Research 66, no. 1 (March 27, 2020): 102–14. http://dx.doi.org/10.30758/0555-2648-2020-66-1-102-114.

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This work describes the practical implementation of the method for digital noise suppression during processing images containing ice information to recognize automatically the contours of «ice-water» objects during aerial photography. Images containing ice information have special characteristic structural features related to noise, e.g.granularity, glare, ice crumbs. This makes difficult or even impossible to recognize automatically the contours of ice-water objects. It is known that the success of the application of edge recognition methods depends on how much image noise is reduced. The paper discusses the construction method for the management of noise. The method is based on the sequential application of the Haar wavelet transform denoising using thresholding, clustering by k-means method. For the subsequent automatic construction of ice floes contours the Sobel operator is applied.The aim of the work is to develop a method capable to process digital images effectively that contain ice information with strong digital noise. In this work we treated the images of one-year ice containing strong digital image noise in the form of granularity and in the form of ice crumbs. A description of the features of each of the steps of the proposed method and practical application is given.As a result, the method was developed for processing images of ice information containing digital noise in absolute value commensurate with the basic data. It was noted that the use of the k-means method expands the scope. The k-rare method allows more detailed processing of ice information and distinguishes not only the contours of ice-water objects, but also the contours of ice crumbs.The conclusion formulates the main advantages of the method and the possible application of the algorithm in the process of local exploration of the ice conditions of the Northern Sea Route channel using unmanned aerial vehicle for aerial photography. The usage of unmanned aerial vehicle for aerial photography will increase the frequency of weather forecast updates and predict the appearance of ice objects at the ship’s heading. That will allow us to select the safest and most economical efficient route along the Northern Sea Route.The authors have no competing interests.

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Hartcher, Michael G., and Rezaul K. Chowdhury. "An alternative method for estimating total impervious area in catchments using high-resolution colour aerial photography." Water Practice and Technology 12, no. 2 (June 1, 2017): 478–86. http://dx.doi.org/10.2166/wpt.2017.053.

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Estimation of total impervious area (TIA) is a pre-requisite for ecohydrological research to allow for a direct prediction on stream ecosystem health within catchments. This paper presents an alternative to using multi-spectral imagery for estimating TIA at a catchment scale, by using high-resolution colour aerial photography. The method was applied to a number of catchments in South East Queensland, Australia, some of which were gauged and some of which were part of an Ecosystem Health Monitoring Program (EHMP). The results from this method were compared to TIA estimates, for some of the same catchments, that were derived through three other techniques, i.e. manual digitization of geo-referenced aerial photos, Brisbane City Council data derived from image analysis using Landsat TM imagery and rainfall runoff depth relationship. The high-resolution colour aerial photography method compared favourably to the other techniques with standard deviations of TIA (%) ranging between 0.8% and 8%. The major constraints were shading effects, particularly on roads and grassed areas, and from the similarity in colours between some surface types, some of which can be reduced by appropriate selection of signature colours and multiple iterations of a supervised classification. It was concluded that while infra-red spectral wave bands could help considerably, the high-resolution colour photography could be applied with confidence to derive catchment-scale TIA estimates.

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Maneas, Giorgos, Eirini Makopoulou, Dimitris Bousbouras, Håkan Berg, and Stefano Manzoni. "Anthropogenic Changes in a Mediterranean Coastal Wetland during the Last Century—The Case of Gialova Lagoon, Messinia, Greece." Water 11, no. 2 (February 19, 2019): 350. http://dx.doi.org/10.3390/w11020350.

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Human interventions during the last 70 years have altered the characteristics of the Gialova Lagoon, a coastal wetland that is part of a wider Natura 2000 site. In this study, we explore how human interventions and climate altered the wetland’s hydrological conditions and habitats, leading to changing wetland functions over time. Our interpretations are based on a mixed methodological approach combining conceptual hydrologic models, analysis of aerial photographs, local knowledge, field observations, and GIS (Geographic Information System) analyses. The results show that the combined effects of human interventions and climate have led to increased salinity in the wetland over time. As a result, the fresh and brackish water marshes have gradually been turned into open water or replaced by halophytic vegetation with profound ecological implications. Furthermore, current human activities inside the Natura 2000 area and in the surrounding areas could further impact on the water quantity and quality in the wetland, and on its sensitive ecosystems. We suggest that a more holistic understanding of the broader socio-ecological system is needed to understand the dynamics of the wetland and to achieve sustainable long-term management and conservation strategies.

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Ambrosini, Ilaria, Lodovico Gherardi, Maria Laura Viti, Giorgio Maresi, and Tullio Turchetti. "Monitoring diseases of chestnut stands by small format aerial photography." Geocarto International 12, no. 3 (September 1997): 41–46. http://dx.doi.org/10.1080/10106049709354595.

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Ye, Dongmei, Ming Liao, Ao Nan, Enquan Wang, and Gaowei Zhou. "RESEARCH ON REEF BATHYMETRIC SURVEY OF UAV STEREOPAIR BASED ON TWO-MEDIUM PHOTOGRAMMETRY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 3, 2016): 407–12. http://dx.doi.org/10.5194/isprsarchives-xli-b1-407-2016.

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This paper is based on the principles of two-medium photogrammetry, with the purpose to perform a bathymetric survey of a reef in the South China Sea, using aerial imagery acquired by UAV. The first objectives are to introduce the basic principles of two-medium photogrammetry, discuss the technical requirements of this methodology to determine an accurate refractive index of sea water, and propose a new method to calculate seawater refraction and calculate corrected reef elevations. The second objective is to analyse and integrate the elevation and depth datum for both the land mass and the undersea reef. The final objective of this paper is performing stereoscopic mensuration on the UAV photography in order to transform reef elevation and depth datum. Our test shows that aerial two-medium photogrammetry is feasible in practical application, but requires relatively high aerial photography conditions.

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Ye, Dongmei, Ming Liao, Ao Nan, Enquan Wang, and Gaowei Zhou. "RESEARCH ON REEF BATHYMETRIC SURVEY OF UAV STEREOPAIR BASED ON TWO-MEDIUM PHOTOGRAMMETRY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 3, 2016): 407–12. http://dx.doi.org/10.5194/isprs-archives-xli-b1-407-2016.

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This paper is based on the principles of two-medium photogrammetry, with the purpose to perform a bathymetric survey of a reef in the South China Sea, using aerial imagery acquired by UAV. The first objectives are to introduce the basic principles of two-medium photogrammetry, discuss the technical requirements of this methodology to determine an accurate refractive index of sea water, and propose a new method to calculate seawater refraction and calculate corrected reef elevations. The second objective is to analyse and integrate the elevation and depth datum for both the land mass and the undersea reef. The final objective of this paper is performing stereoscopic mensuration on the UAV photography in order to transform reef elevation and depth datum. Our test shows that aerial two-medium photogrammetry is feasible in practical application, but requires relatively high aerial photography conditions.

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Talebi, Leila, Anika Kuczynski, Andrew J. Graettinger, and Robert Pitt. "Automated Classification of Urban Areas for Storm Water Management Using Aerial Photography and LiDAR." Journal of Hydrologic Engineering 19, no. 5 (May 2014): 887–95. http://dx.doi.org/10.1061/(asce)he.1943-5584.0000815.

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König, Max, and Matthew Sturm. "Mapping snow distribution in the Alaskan Arctic using aerial photography and topographic relationships." Water Resources Research 34, no. 12 (December 1998): 3471–83. http://dx.doi.org/10.1029/98wr02514.

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Huang, Chao, Hongmei Zhang, and Jianhu Zhao. "High-Efficiency Determination of Coastline by Combination of Tidal Level and Coastal Zone DEM from UAV Tilt Photogrammetry." Remote Sensing 12, no. 14 (July 8, 2020): 2189. http://dx.doi.org/10.3390/rs12142189.

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To meet the needs of coastline efficient extraction and dynamic monitoring, this paper proposes a new method for coastline extraction by combining the tidal level and the digital elevation model (DEM) of the coastal zone from tilt photography. Firstly, the DEM of coastal zone was obtained by using unmanned aerial vehicle (UAV) tilt photography; at the same time, the accuracy of aerial triangulation(AT) is improved referencing to the constraint of water boundary points, and then the mean high water spring tide was obtained by combining tidal harmonic analysis and Global Navigation Satellite System (GNSS) tidal level. Finally, the coastline and the dynamic water-surface line are extracted from the DEM of the coastal zone by tracking the contour lines with the elevation of the mean high water springs (MHWS) and the instantaneous sea-surface elevation, respectively. The experiments carried out in the coastal zones of Liaoning Province, China, proved the proposed method and achieved better than 0.2 m of horizontal position accuracy and 0.1 m of the vertical accuracy.

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Yang, Chenghai, James H. Everitt, and John A. Goolsby. "Mapping Giant Reed (Arundo donax) Infestations along the Texas–Mexico Portion of the Rio Grande with Aerial Photography." Invasive Plant Science and Management 4, no. 4 (December 2011): 402–10. http://dx.doi.org/10.1614/ipsm-d-10-00081.1.

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AbstractGiant reed is an invasive weed throughout the southern half of the United States, with the densest stands growing along the coastal rivers of southern California and the Rio Grande in Texas. The objective of this study was to use aerial photography to map giant reed infestations and to estimate infested areas along the Texas–Mexico portion of the Rio Grande. Aerial color-infrared photographs were taken along the Rio Grande between Brownsville and El Paso, TX, in June and July 2002. Based on the aerial photographs and ground surveys, the portion of the river from San Ygnacio to Lajitas, which has a river length of 898 km (558 mi), was found to be infested with giant reed. To estimate infested areas along both sides of the river, 65 (13.5%) of the 480 aerial photographs taken between Lajitas and San Ygnacio were randomly selected. The aerial photographs were digitized, rectified to Google Earth imagery, and then classified using maximum-likelihood classification techniques. The infested areas on both sides of the river, as well as water area and river length, from each photographic image were determined. Based on the estimates from the 65 aerial photos, the ratio of giant reed area to water area and the ratio of giant reed area to river length were calculated. The total giant reed area along the Rio Grande between Lajitas and San Ygnacio was estimated to be 5,981 ha (14,779 ac) with 3,714 ha or 62% on the U.S. side and 2,267 ha or 38% on the Mexican side. This study provides the first accurate estimates of giant reed infestations along the Texas–Mexico portion of the Rio Grande and will be useful for both land owners and government agencies for the estimation of water usage and economic loss and for the management and control of giant reed.

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Resler, Lynn M., Mark A. Fonstad, and David R. Butler. "Mapping the Alpine Treeline Ecotone with Digital Aerial Photography and Textural Analysis." Geocarto International 19, no. 1 (March 2004): 37–44. http://dx.doi.org/10.1080/10106040408542297.

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Everitt, J. H., C. Yang, and M. R. Davis. "Mapping an annual weed with colour-infrared aerial photography and image analysis." Geocarto International 25, no. 1 (February 2010): 45–52. http://dx.doi.org/10.1080/10106040802677037.

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Moraru, Adina, Michal Pavlíček, Oddbjørn Bruland, and Nils Rüther. "The Story of a Steep River: Causes and Effects of the Flash Flood on 24 July 2017 in Western Norway." Water 13, no. 12 (June 18, 2021): 1688. http://dx.doi.org/10.3390/w13121688.

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Flash floods can cause great geomorphological changes in ephemeral fluvial systems and result in particularly severe damages for the unprepared population exposed to it. The flash flood in the Storelva river in Utvik (western Norway) on 24 July 2017 was witnessed and documented. This study assessed the causes and effects of the 2017 flood and provides valuable information for the calibration and validation of future modelling studies. The flooded area at peak discharge, maximum wetted and dry areas during the entire event, critical points and main flow paths were reconstructed using on-site and post-event (i) visual documentation, such as photographs and videos, and (ii) aerial surveying, such as orthophotographs and laser scanning, of the lowermost reach. The steep longitudinal slope together with the loose material forming the valley and riverbed contributed to a large amount of sediment transport during this extreme event. Steep rivers such as the Storelva river have very short response times to extreme hydrologic conditions, which calls for exhaustive monitoring and data collection in case of future events, as well as modelling tools that can emulate the hydro-morphodynamics observed during events such as the 2017 flash flood.

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Everitt, J. H., C. Yang, R. S. Fletcher, M. R. Davis, and D. L. Drawe. "Using Aerial Color‐infrared Photography and QuickBird Satellite Imagery for Mapping Wetland Vegetation." Geocarto International 19, no. 4 (December 2004): 15–22. http://dx.doi.org/10.1080/10106040408542323.

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Anderson, G. L., J. H. Everitt, D. E. Escobar, N. R. Spencer, and R. J. Andrascik. "Mapping leafy spurge (euphorbia esula) infestations using aerial photography and geographic information systems." Geocarto International 11, no. 1 (March 1996): 81–89. http://dx.doi.org/10.1080/10106049609354526.

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Porwal, Mahesh C., and Parth S. Roy. "Attempted Understorey Characterization Using Aerial Photography in Kanha National Park, Madhya Pradesh, India." Environmental Conservation 18, no. 1 (1991): 45–50. http://dx.doi.org/10.1017/s0376892900021299.

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Remote sensing is being widely used in the fields of resource management, planning, and wildlife habitat evaluation. Canopy cover-type mapping has been done in most of the bioclimatic zones of India and widely abroad, using aerial photointerpretation techniques. In the present study an attempt has been made to develop a methodology for mapping understorey vegetation in part of Kanha National Park, using 1:10,000-scale black-and-white aerial photographs.The Park, one of the best for Tiger (Felis tigris) visibility and observation of other large carnivores and herbivores, has been mapped, with subdivision into 11 vegetation cover-classes and four density-classes, using aerial photographs, and each class has been visited in the field for understorey information concerning different physiographic units. Each category of canopy-cover was sampled in the field, and tree base-cover per hectare has been estimated.Vertical profiles have also been drawn in the main vegetation classes in order to understand the occurrence of understorey vegetation. It was found that a physiographic analysis coupled with canopy-cover type and density, with appropriate sampling in the individual vegetation strata, have together proved indicative of understorey vegetationtype. When the relationship between understorey vegetation and canopy-cover type is established, one can directly depict understorey limits spatially in conjunction with the main vegetation cover. Such an approach of mapping understorey vegetation using aerial photographs could be of immense value for wildlife habitat evaluation and park management.

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Jenčo, Marián, Emil Fulajtár, Hana Bobáľová, Igor Matečný, Martin Saksa, Miroslav Kožuch, Michal Gallay, Ján Kaňuk, Vladimír Píš, and Veronika Oršulová. "Mapping Soil Degradation on Arable Land with Aerial Photography and Erosion Models, Case Study from Danube Lowland, Slovakia." Remote Sensing 12, no. 24 (December 10, 2020): 4047. http://dx.doi.org/10.3390/rs12244047.

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The presented study uses the recent colour aerial photographs, historical black and white aerial photographs, and detailed digital elevation model to assess the spatial distribution and long-term temporal dynamics of soil loss in agriculturally intensively exploited loess hilly land with a subcontinental temperate climate. The strongly eroded soils appear in the studied area as bright patterns, surrounded by darker soils, and they are well visible on aerial photos. Three approaches of interpretation of aerial photographs were tested: visual interpretation, pixel-based image classification, and object-based image classification. All three methods provided detailed maps of soil redistribution patterns. The bright areas as the areas of soil degradation characterized by erosion increased from 1949 until 2011 by 76%. A detailed map of areal erosion patterns was used for the validation of water erosion models. LS-factor of USLE and ED’ index of USPED were selected for expressing the relation of real erosion to the terrain. The relationship between surface morphology and real erosion is very complex, and the tested water erosion models do not express it sufficiently. Therefore, the first and second-order directional derivative of the surface elevations with respect to the tillage direction has been tested. The absolute value of the first-order directional derivative showed better results and better corresponded with the real erosion pattern than the other morphometric characteristics. The findings suggest that tillage is the dominant erosion factor in the area.

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Pfister, Laurent, Carlos E. Wetzel, Núria Martínez-Carreras, Jean François Iffly, Julian Klaus, Ladislav Holko, and Jeffrey J. McDonnell. "Examination of aerial diatom flushing across watersheds in Luxembourg, Oregon and Slovakia for tracing episodic hydrological connectivity." Journal of Hydrology and Hydromechanics 63, no. 3 (September 1, 2015): 235–45. http://dx.doi.org/10.1515/johh-2015-0031.

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Abstract Hydrological processes research remains a field that is severely measurement limited. While conventional tracers (geochemicals, isotopes) have brought extremely valuable insights into water source and flowpaths, they nonetheless have limitations that clearly constrain their range of application. Integrating hydrology and ecology in catchment science has been repeatedly advocated as offering potential for interdisciplinary studies that are eventually to provide a holistic view of catchment functioning. In this context, aerial diatoms have been shown to have the potential for detecting of the onset/cessation of rapid water flowpaths within the hillslope-riparian zone-stream continuum. However, many open questions prevail as to aerial diatom reservoir size, depletion and recovery, as well as to their mobilisation and transport processes. Moreover, aerial diatoms remain poorly known compared to freshwater species and new species are still being discovered. Here, we ask whether aerial diatom flushing can be observed in three catchments with contrasting physiographic characteristics in Luxembourg, Oregon (USA) and Slovakia. This is a prerequisite for qualifying aerial diatoms as a robust indicator of the onset/cessation of rapid water flowpaths across a wider range of physiographical contexts. One species in particular, (Hantzschia amphioxys (Ehr.) Grunow), was found to be common to the three investigated catchments. Aerial diatom species were flushed, in different relative proportions, to the river network during rainfall-runoff events in all three catchments. Our take-away message from this preliminary examination is that aerial diatoms appear to have a potential for tracing episodic hydrological connectivity through a wider range of physiographic contexts and therefore serve as a complementary tool to conventional hydrological tracers.

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Richard, Hodgkins, and Julian A. Dowdeswell. "Tectonic processes in Svalbard tide-water glacier surges: evidence from structural glaciology." Journal of Glaciology 40, no. 136 (1994): 553–60. http://dx.doi.org/10.1017/s0022143000012430.

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AbstractThe tectonic effects of a glacier surge differ from those of steady state because flow is driven by longitudinal stresses rather than shear stresses. The orientations of recently formed crevasses, indicating the directions of the principal stresses, have been used to investigate tectonic processes in glacier surges recorded by repeat aerial photography. Long-term, large-magnitude shifts in stress regime are demonstrated, as are short-term propagation features. Two types of tide-water glacier advance are identified, depending on the position of the surge front relative to a low effective-pressure zone at the glacier terminus.

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Richard, Hodgkins, and Julian A. Dowdeswell. "Tectonic processes in Svalbard tide-water glacier surges: evidence from structural glaciology." Journal of Glaciology 40, no. 136 (1994): 553–60. http://dx.doi.org/10.3189/s0022143000012430.

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AbstractThe tectonic effects of a glacier surge differ from those of steady state because flow is driven by longitudinal stresses rather than shear stresses. The orientations of recently formed crevasses, indicating the directions of the principal stresses, have been used to investigate tectonic processes in glacier surges recorded by repeat aerial photography. Long-term, large-magnitude shifts in stress regime are demonstrated, as are short-term propagation features. Two types of tide-water glacier advance are identified, depending on the position of the surge front relative to a low effective-pressure zone at the glacier terminus.

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Kingsley, Michael CS, and Isabelle Gauthier. "Visibility of St Lawrence belugas to aerial photography, estimated by direct observation." NAMMCO Scientific Publications 4 (July 22, 2002): 259. http://dx.doi.org/10.7557/3.2848.

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The depleted population of belugas (Delphinapterus leucas) inhabiting the St Lawrence estuary, Canada, was monitored by periodic photographic aerial surveys. In order to correct counts made on aerial survey film and to obtain an estimate of the true size of the population, the diving behaviour and the visibility from the air of these animals was studied. A Secchi-disk turbidity survey in the belugas’ summer range showed that water clarity varied between 1.5 m and 11.6 m. By studying aerial photographs of sheet-plastic models of belugas that had been sunk to different depths below the surface, we found that models of white adults could be seen down to about the same depth as a Secchi disk, but no deeper. Smaller models of dark-grey juveniles could only be seen down to about 50% of Secchi-disk depth. By observing groups of belugas from a hovering helicopter and recording their disappearances and re-appearances, it was found that they were visible for 44.3% of the time, and that an appropriate correction for single photographs would be to multiply the photographic count by about 222% (SE 20%). For surveys in which there was overlap between adjacent frames, the estimated correction would be 209% (SE 16%). This correction factor was slightly conservative and gave an estimate of the true size of the population, based on a single survey, of 1,202 belugas (SE 189) in 1997. An estimate for 1997 based on smoothing 5 surveys 1988–1997 was 1,238 (SE 119).

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Abisheva, Mariya T., and Helena P. Khlebnikova. "INTEGRATED USE OF AERIAL AND GROUND-BASED MEASUREMENT DATA TO ASSESS THE RADIATION SITUATION OF WATER BODIES." Vestnik SSUGT (Siberian State University of Geosystems and Technologies) 26, no. 1 (2021): 68–75. http://dx.doi.org/10.33764/2411-1759-2021-26-1-68-75.

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Currently, a promising area is the use of the latest technologies and methods aimed at identifying and assessing the condition of objects. The purpose of this work is to improve the technological scheme for environmental monitoring. The proposed method is based on the results of integrated ap-plication of aerial photography and ground-based measurements for environmental monitoring in as-sessing the state of water bodies in radioecologically dangerous territories. As a result of this work, the sequence of work was described both when obtaining data using unmanned aerial vehicles and their subsequent photogrammetric processing, and when performing measurements using ground-based in-strumental methods. A technological scheme is presented that allows integrating information obtained by various methods, which can be entered into modeling systems and predict the behavior of a water body depending on changes in natural and anthropogenic impacts.

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Sedykh, V. N. "Using aerial photography and satellite imagery to monitor forest cover in western Siberia." Water, Air, & Soil Pollution 82, no. 1-2 (May 1995): 499–507. http://dx.doi.org/10.1007/bf01182859.

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Hammer, Emily. "THE CITY AND LANDSCAPE OF UR: AN AERIAL, SATELLITE, AND GROUND REASSESSMENT." Iraq 81 (October 18, 2019): 173–206. http://dx.doi.org/10.1017/irq.2019.7.

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New fieldwork at Ur has begun to investigate urban scale, city organization, and the environment of the city's hinterland. Analysis of new sources of declassified aerial and satellite imagery from the 1950s and 1960s, recent unmanned aerial vehicle (UAV) photos, and a systematic surface collection show that Ur may have expanded to between 120–500 hectares in size during its later periods of habitation, far larger than the sixty hectare maximum size previously estimated. Traces of buried architecture visible in the UAV photos and topographic models generated from UAV photos allow for the generation of hypotheses about the city plan of Ur during the Late Larsa/Old Babylonian and Neo Babylonian periods. Relict watercourses mapped in the vicinity of the main mound indicate how the city might have been supplied with water in some periods. Alongside this site-based work, historical aerial and satellite imagery provide an updated picture of ancient hydrology, environment, and settlement patterns around Ur.

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Fletcher, Reginald S., Warren Pulich, and Beau Hardegree. "A Semiautomated Approach for Monitoring Landscape Changes in Texas Seagrass Beds from Aerial Photography." Journal of Coastal Research 252 (March 2009): 500–506. http://dx.doi.org/10.2112/07-0882.1.

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Salama, R. B., I. Tapley, T. Ishii, and G. Hawkes. "Identification of areas of recharge and discharge using Landsat-TM satellite imagery and aerial photography mapping techniques." Journal of Hydrology 162, no. 1-2 (October 1994): 119–41. http://dx.doi.org/10.1016/0022-1694(94)90007-8.

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Wright, G. G., K. B. Matthews, J. C. Tapping, and R. Wright. "Combining Metric Aerial Photography and Near‐Infrared Videography to Define Within‐Field Soil Sampling Frameworks." Geocarto International 18, no. 4 (December 2003): 13–20. http://dx.doi.org/10.1080/10106040308542285.

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Biggin, D. S. "A Comparison of ERS-1 Satellite Radar and Aerial Photography for River Flood Mapping." Water and Environment Journal 10, no. 1 (February 1996): 59–64. http://dx.doi.org/10.1111/j.1747-6593.1996.tb00009.x.

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Journal articles on the topic 'Water Aerial photography in hydrology'

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