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Journal articles on the topic 'Aerial photography in ecology'

Author: Grafiati

Published: 4 June 2021

Last updated: 3 March 2023

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1

Scott, Samantha L., Rick Rohde, and Timm Hoffman. "Repeat Landscape Photography, Historical Ecology and the Wonder of Digital Archives in Southern Africa." African Research & Documentation 131 (2017): 35–47. http://dx.doi.org/10.1017/s0305862x00022512.

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Environmental history projects using repeat photography often involve the acquisition of large collections of historical and current images, matching those images for comparative analysis, and then cataloguing and archiving the imagery for long-term storage and later use (Webb et ah, 2010). When used in combination with other techniques, repeat photography is an excellent tool for documenting change (Gruell, 2010) and has been used in a variety of disciplines, including historical ecology, to determine changes in plant populations, soil erosion, climate trends and ecological processes to name a few. Historical photographs often provide greater temporal range to an analysis compared to, for example, satellite imagery and in many cases even aerial photography (Gruell, 2010).

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Scott, Samantha L., Rick Rohde, and Timm Hoffman. "Repeat Landscape Photography, Historical Ecology and the Wonder of Digital Archives in Southern Africa." African Research & Documentation 131 (2017): 35–47. http://dx.doi.org/10.1017/s0305862x00022512.

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Environmental history projects using repeat photography often involve the acquisition of large collections of historical and current images, matching those images for comparative analysis, and then cataloguing and archiving the imagery for long-term storage and later use (Webb et ah, 2010). When used in combination with other techniques, repeat photography is an excellent tool for documenting change (Gruell, 2010) and has been used in a variety of disciplines, including historical ecology, to determine changes in plant populations, soil erosion, climate trends and ecological processes to name a few. Historical photographs often provide greater temporal range to an analysis compared to, for example, satellite imagery and in many cases even aerial photography (Gruell, 2010).

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3

Fensham, R. J., and R. J. Fairfax. "Assessing woody vegetation cover change in north-west Australian savanna using aerial photography." International Journal of Wildland Fire 12, no. 4 (2003): 359. http://dx.doi.org/10.1071/wf03022.

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Models to calibrate tree and shrub cover assessed from aerial photography with field measurements were developed for a range of vegetation types in north-western Australia. The models verify previous studies indicating that woody cover can be successfully determined from aerial photography. The calibration models were applied to estimates of woody vegetation cover determined for 279 randomly located sample areas in the Ord–Victoria Rivers region using aerial photography from 1948 to 1950 and 1988 to 1997. Overstorey cover increased from a regional average of 11.5% to 13.5% and understorey cover increased from 1.3% to 2.0%. Downs, Limestone Hills and Alluvia land-types showed the most substantial increases in overstorey cover while overstorey cover in the Limestone plains land-type decreased. Relatively open structured vegetation is most susceptible to thickening. Rainfall records reveal an extreme multi-year rainfall deficit in the study area in the 1930s and relatively wet times in the 1970s and 1980s. Interpretation of a limited set of aerial photographs taken between 1964 and 1972 suggests that most of the increases in cover have occurred since this time. The study highlights the possibility that the average trend of vegetation thickening represents recovery during the relatively wet times after the 1970s. There was no relationship between structural change and a grazing intensity surrogate (distance of sample points to stock watering-points). However, the causes of structural change are undoubtedly multi-factored and the relative contributions of climate, fire and grazing vary for different landscapes and tree species.

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Fairfax, R. J., and R. J. Fensham. "Corrigendum to: Assessing woody vegetation cover change in north-west Australian savanna using aerial photography." International Journal of Wildland Fire 13, no. 1 (2004): 131. http://dx.doi.org/10.1071/wf03022_co.

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Models to calibrate tree and shrub cover assessed from aerial photography with field measurements were developed for a range of vegetation types in north-western Australia. The models verify previous studies indicating that woody cover can be successfully determined from aerial photography. The calibration models were applied to estimates of woody vegetation cover determined for 279 randomly located sample areas in the Ord–Victoria Rivers region using aerial photography from 1948 to 1950 and 1988 to 1997. Overstorey cover increased from a regional average of 11.5% to 13.5% and understorey cover increased from 1.3% to 2.0%. Downs, Limestone Hills and Alluvia land-types showed the most substantial increases in overstorey cover while overstorey cover in the Limestone plains land-type decreased. Relatively open structured vegetation is most susceptible to thickening. Rainfall records reveal an extreme multi-year rainfall deficit in the study area in the 1930s and relatively wet times in the 1970s and 1980s. Interpretation of a limited set of aerial photographs taken between 1964 and 1972 suggests that most of the increases in cover have occurred since this time. The study highlights the possibility that the average trend of vegetation thickening represents recovery during the relatively wet times after the 1970s. There was no relationship between structural change and a grazing intensity surrogate (distance of sample points to stock watering-points). However, the causes of structural change are undoubtedly multi-factored and the relative contributions of climate, fire and grazing vary for different landscapes and tree species.

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5

Zagalikis, G., A. D. Cameron, and D. R. Miller. "The application of digital photogrammetry and image analysis techniques to derive tree and stand characteristics." Canadian Journal of Forest Research 35, no. 5 (2005): 1224–37. http://dx.doi.org/10.1139/x05-030.

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Ground-based forest inventory surveys can provide highly accurate measurements of tree and stand characteristics, but these are expensive to carry out. Aerial photography has been used for several decades as a tool in forest management and inventory. However, conventional methods of interpretation are both time-consuming and costly, with results varying among interpreters. With continuing development of personal computer technology, aerial photographs have become more accessible for digital analysis. This paper presents the potential operational use of digitized aerial photographs for the estimation of tree and stand characteristics of two forest plantations of Sitka spruce (Picea sitchensis (Bong.) Carrière) in Scotland. The digitized aerial photographs were processed using softcopy photogrammetry, and image analysis techniques were used for individual tree crown delineation. For the first site the estimations of stand top height, basal area, volume, biomass, and density (23.7%) were similar to the ground-measured stand characteristics (±10%), whereas for the second site the estimations were less accurate mainly because of the nonoptimal illumination conditions during the acquisition of the aerial photographs.

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Meulstee, C., P. H. Nienhuis, and H. T. C. Van Stokkom. "Biomass assessment of estuarine macrophytobenthos using aerial photography." Marine Biology 91, no. 3 (1986): 331–35. http://dx.doi.org/10.1007/bf00428626.

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7

Alemdag, I. S. "Estimating ovendry mass of trembling aspen and white birch using measurements from aerial photographs." Canadian Journal of Forest Research 16, no. 1 (1986): 163–65. http://dx.doi.org/10.1139/x86-030.

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A pilot study tested the estimation of stem, crown, and whole-tree biomass of single trees from measurements of total tree height and crown area taken from large-scale aerial photographs. The results indicated the feasibility of this method, provided that time of photography is optimal. More extensive testing is required to confirm these encouraging preliminary results.

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8

Booth, D. Terrance, Samuel E. Cox, and Gregg Simonds. "Riparian monitoring using 2-cm GSD aerial photography." Ecological Indicators 7, no. 3 (2007): 636–48. http://dx.doi.org/10.1016/j.ecolind.2006.07.005.

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9

Fensham, R. J., and R. J. Fairfax. "Effect of photoscale, interpreter bias and land type on woody crown-cover estimates from aerial photography." Australian Journal of Botany 55, no. 4 (2007): 457. http://dx.doi.org/10.1071/bt05211.

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Woody vegetation cover interpreted from aerial photography requires assessment against field data as the signature of woody vegetation cover may differ between photoscales, vegetation types and photo-interpreters. Measurements of aerial woody cover taken from aerial photography of four different photoscales were compared with a field dataset from Eucalyptus- and Acacia-dominated landscapes of semi-arid Queensland. Two interpreters employed a method that utilises a stereoscope and sample-point graticule for manual quantified measurements of aerial woody cover. Both interpreters generated highly significant models accounting for 77 and 78% of deviance. Photoscale appears to have a consistent effect whereby the signature of woody cover increases as the photoscale decreases from 1 : 25 000 to 1 : 80 000, although the magnitude of this effect was different between interpreters. The results suggest no substantial differences in the shape of models predicting crown cover between Acacia- and Eucalyptus-dominated land types, although the precision of the models was greater for the Acacia (90–91% of residual deviance) than for the Eucalyptus (50–56% of residual deviance) land type. The reduced accuracy in the Eucalyptus land type probably reflects the relatively diffuse crowns of the dominant trees. The models generated for this dataset are within the range of those from other calibration studies employing photography of a range of scales and methodologies. The effect of photoscale is verified between the available studies, but there may also be variations arising from methodological differences or image properties. The present study highlights the influence of photoscale and interpreter bias for assessing woody crown cover from aerial photography. Studies that employ aerial photography should carefully consider potential biases and cater for them by calibrating assessments with field measurements.

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Hardin, Perry J., and Mark W. Jackson. "An Unmanned Aerial Vehicle for Rangeland Photography." Rangeland Ecology & Management 58, no. 4 (2005): 439–42. http://dx.doi.org/10.2111/1551-5028(2005)058[0439:auavfr]2.0.co;2.

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Browning, D. M., S. R. Archer, and A. T. Byrne. "Field validation of 1930s aerial photography: What are we missing?" Journal of Arid Environments 73, no. 9 (2009): 844–53. http://dx.doi.org/10.1016/j.jaridenv.2009.04.003.

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Naylor, Bridgett J., Bryan A. Endress, and Catherine G. Parks. "Multiscale Detection of Sulfur Cinquefoil Using Aerial Photography." Rangeland Ecology & Management 58, no. 5 (2005): 447–51. http://dx.doi.org/10.2111/1551-5028(2005)58[447:mdoscu]2.0.co;2.

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Massada, Avi Bar, Yohay Carmel, Gilad Even Tzur, José M. Grünzweig, and Dan Yakir. "Assessment of temporal changes in aboveground forest tree biomass using aerial photographs and allometric equations." Canadian Journal of Forest Research 36, no. 10 (2006): 2585–94. http://dx.doi.org/10.1139/x06-152.

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Studies of forest biomass dynamics typically use long-term forest inventory data, available in only a few places around the world. We present a method that uses photogrammetric measurements from aerial photographs as an alternative to time-series field measurements. We used photogrammetric methods to measure tree height and crown diameter, using four aerial photographs of Yatir Forest, a semi-arid forest in southern Israel, taken between 1978 and 2003. Height and crown-diameter measurements were transformed to biomass using an allometric equation generated from 28 harvested Aleppo pine (Pinus halepensis Mill.) trees. Mean tree biomass increased from 6.37 kg in 1978 to 97.01 kg in 2003. Mean plot biomass in 2003 was 2.48 kg/m2 and aboveground primary productivity over the study period ranged between 0.14 and 0.21 kg/m2 per year. There was systematic overestimation of tree height and systematic underestimation of crown diameter, which was corrected for at all time points between 1978 and 2003. The estimated biomass was significantly related to field-measured biomass, with an R2 value of 0.78. This method may serve as an alternative to field sampling for studies of forest biomass dynamics, assuming that there is sufficient spatial and temporal coverage of the investigated area using high-quality aerial photography, and that the tree tops are distinguishable in the photographs.

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González-Orozco, Carlos E., Mark Mulligan, Valérie Trichon, and Andrew Jarvis. "Taxonomic identification of Amazonian tree crowns from aerial photography." Applied Vegetation Science 13, no. 4 (2010): 510–19. http://dx.doi.org/10.1111/j.1654-109x.2010.01090.x.

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15

Rackham, O. "WOODLAND ECOLOGY IN RECENT AND HISTORIC AERIAL PHOTOGRAPHS." Photogrammetric Record 14, no. 80 (2006): 227–39. http://dx.doi.org/10.1111/j.1477-9730.1992.tb00248.x.

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Petersen, Steven L., Tamzen K. Stringham, and Andrea S. Laliberte. "Classification of Willow Species Using Large-Scale Aerial Photography." Rangeland Ecology & Management 58, no. 6 (2005): 582–87. http://dx.doi.org/10.2111/04-129r1.1.

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17

Delord, Karine, Gildas Roudaut, Christophe Guinet, Christophe Barbraud, Sophie Bertrand, and Henri Weimerskirch. "Kite aerial photography: a low-cost method for monitoring seabird colonies." Journal of Field Ornithology 86, no. 2 (2015): 173–79. http://dx.doi.org/10.1111/jofo.12100.

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18

Kelly, Kevin. "Determination of Lobster Trap Density near Midcoastal Maine by Aerial Photography." North American Journal of Fisheries Management 13, no. 4 (1993): 859–63. http://dx.doi.org/10.1577/1548-8675(1993)013<0859:doltdn>2.3.co;2.

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19

Rugh, David J., Howard W. Braham, and Gary W. Miller. "Methods for photographic identification of bowhead whales, Balaena mysticetus." Canadian Journal of Zoology 70, no. 3 (1992): 617–24. http://dx.doi.org/10.1139/z92-090.

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Bowhead whales, Balaena mysticetus, have black skin except for patterns of white along their ventral surface and visible dorsally on their lower jaws, caudal peduncles, and flukes. White scar marks may also be present. These contrasting black and white dorsal patterns were examined in 4871 aerial photographs of bowheads taken from 1976 to 1987 to determine if individual animals could be reidentified when subsequently photographed. The objective of making such reidentifications was to provide important life-history information, such as calving intervals, length-specific growth rates, survival rates, and population abundance. This paper describes procedures developed to categorize whales into 20 file types based on the relative extent of visible white markings. Preliminary analysis of the photographic identification system suggests that it has a high potential for use in population studies but only if whale images are of sufficient quality and quantity to allow for multiple reidentifications. High-quality images are best obtained from aerial photographs taken directly above whales in clear water during good to excellent sea-state conditions without glare. This ensures that sufficient characteristic features, if present, are photographed to permit recognition in subsequent photographs.

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Greenfield, L. G., and K. J. Wilson. "Adélie penguin colony estimations from aerial photography and ground counts." Polar Record 27, no. 161 (1991): 129–30. http://dx.doi.org/10.1017/s0032247400012262.

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21

Estep, K. "Seal sizes and habitat conditions assessed from aerial photography and video analysis." ICES Journal of Marine Science 51, no. 3 (1994): 253–61. http://dx.doi.org/10.1006/jmsc.1994.1026.

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22

Parker, William H., Annette van Niejenhuis, and Laird Van Damme. "Base-line selection of black spruce by large-scale aerial photography." Canadian Journal of Forest Research 18, no. 3 (1988): 380–83. http://dx.doi.org/10.1139/x88-056.

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Following selection of black spruce (Piceamariana (Mill.) B.S.P.) for growing space efficiency using a base line of basal area increment vs. crown length × crown radius, the corresponding crown data were determined by large-scale (1:1250) aerial photography for 174 ground-measured trees to determine whether aerial photography would provide a more accurate and cost-effective alternative for plus-tree selection. Values obtained for ground- and photo-measured tree heights and crown lengths corresponded closely, but values of crown radii measured from the ground by a right-angle prism did not correspond in the same manner to values derived from crown horizontal projection areas on the photos. Nonetheless, the different base lines of basal area increments vs. various ground- and photo-measured crown parameters generally identified the same trees as having the greatest growing space efficiency. The inclusion of crown length together with crown radius did not improve the goodness of fit for regressions of basal area increments vs. crown parameters. Apparently, the two horizontal dimensions are adequate to describe growing space for black spruce, perhaps because its crown form is relatively constant. Our results indicate that large-scale aerial photography is well suited to plus-tree selections of black spruce if ground mesurements are not also required to establish base lines; the extra cost of the photos is offset by the greater speed in measuring tree heights or crown horizontal projection areas. Thus, while the technique is sufficiently accurate, it is not cost effective for establishing growing space efficiency base lines where the basal area increment is determined directly from increment cores.

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Carpenter, Laurel, Janice Stone, and Curtice R. Griffin. "Accuracy of Aerial Photography for Locating Seasonal (Vernal) Pools in Massachusetts." Wetlands 31, no. 3 (2011): 573–81. http://dx.doi.org/10.1007/s13157-011-0169-4.

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Curr, R. H. F., A. Koh, E. Edwards, A. T. Williams, and P. Davies. "Assessing anthropogenic impact on Mediterranean sand dunes from aerial digital photography." Journal of Coastal Conservation 6, no. 1 (2000): 15–22. http://dx.doi.org/10.1007/bf02730463.

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McIlleron, W. Geoff, and Ferdinand C. De Moor. "Photography of Trichoptera in flight." Zoosymposia 5, no. 1 (2011): 297–318. http://dx.doi.org/10.11646/zoosymposia.5.1.23.

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Whereas photography of insects at rest is used for a wide variety of purposes, including illustrating publications and aiding their identification, photography of insects in flight is more challenging and little practiced. This paper describes a system that uses a digital single-lens-reflex camera combined with commercial-level flashes (with electronic power settings to give very short exposures) and simple electronics in a rig that can be used to capture high quality images of night-flying insects. With such a rig, hundreds of images of free flying Trichoptera have been obtained. Preliminary observations of night-flying Athripsodes bergensis (Leptoceridae) indicate that this system could be used for studying the mechanics of flight, wing beat frequency, aerodynamics, flying speed, aerial activity, and behavioural ecology of night-flying insects in their natural environment. This paper briefly describes the technique as applied at a site on the banks of the Groot River in the southern Cape region of South Africa between October 2008 and April 2009 and presents a selection of the images obtained.

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Everitt, J. H. "Using Aerial Photography for Detecting Blackbrush [Acacia rigidula] on South Texas Rangelands." Journal of Range Management 38, no. 3 (1985): 228. http://dx.doi.org/10.2307/3898972.

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Đorđević, Dejan Radovan, Uroš Đurić, Saša Tomislav Bakrač, Siniša Milanko Drobnjak, and Stevan Radojčić. "Using Historical Aerial Photography in Landslide Monitoring: Umka Case Study, Serbia." Land 11, no. 12 (2022): 2282. http://dx.doi.org/10.3390/land11122282.

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The application of remote sensing methods provides useful information that can be used for numerous research. Thus, spatial changes in soil, vegetation, hydrography and such can be analyzed. By analyzing the data obtained by remote sensing methods, high-quality and important data can be obtained for monitoring changes in soil movement caused by landslides. This method provides the possibility of determining the state of the observed space over a longer period of time. Historical aerial imagery has a high level of spatial detail analysis. Comparative analysis of the aerial imagery from the past, recent ones and other surveys can certainly provide information on the trend of ground movement, as well as lead to conclusions for taking specific measures. The present paper gives an example of the analysis of the particular area of the “Umka” landslide based on historical surveys. The “Umka” landslide is located along the right bank of the Sava River near the city of Belgrade, which, with its long-term activity, jeopardizes residential buildings, infrastructure facilities and the population that still lives on it.

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Banfai, Daniel S., and David M. J. S. Bowman. "Dynamics of a savanna-forest mosaic in the Australian monsoon tropics inferred from stand structures and historical aerial photography." Australian Journal of Botany 53, no. 3 (2005): 185. http://dx.doi.org/10.1071/bt04141.

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Stratified ground-truthing was undertaken within an area of approximately 30 km2 of tropical savanna across an abrupt sandstone escarpment in the monsoon tropics of Australia. Comparison of aerial photographs from 1941 and 1994 had previously revealed a landscape-wide expansion of closed forest and contraction of grassland patches. Good congruence between field measurements and the vegetation classifications from the 1994 aerial photography supported the authenticity of the vegetation changes. The relative abundance of rainforest and non-rainforest tree species also concurred with mapped vegetation transitions. Changes in individual size classes of rainforest species, which are relatively fire sensitive, were consistent with the primacy of fire in controlling the distribution of the closed-forest formation. Fire scars previously mapped from satellite imagery were used to derive a fire activity index for contrasting vegetation transitions. Savannas that had converted to closed forest had lower fire activity than did stable savannas. Conversely, closed forests that converted to savanna had the highest fire activity index. The landscape-wide expansion of rainforest is associated with the cessation of Aboriginal fire management, possibly in conjunction with elevated CO2 and increasing annual rainfall.

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Burton, Frederic J., Patricia E. Bradley, Elizabeth A. Schreiber, Gary A. Schenk, and Richard W. Burton. "Status of Red-footed Boobies Sula sula on Little Cayman, British West Indies." Bird Conservation International 9, no. 3 (1999): 227–33. http://dx.doi.org/10.1017/s0959270900003427.

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SummaryThe island of Little Cayman, in the north-west Caribbean, supports a large breeding colony of Red-footed Boobies Sula sula, within a Ramsar site, the Booby Pond Nature Reserve, protected and managed by the National Trust for the Cayman Islands. Comparison of aerial photographs from 1994 and 1997 shows the colony area unchanged over this time period, occupying 16.5 ha. Area sampling yielded an estimate of 4,839 nesting pairs on Little Cayman in 1997, representing c. 30% of the entire Caribbean population for this species. Low mortality and excellent condition of chicks indicated a very successful breeding year with good food availability. Aerial photography proved to be an effective tool for determining the colony area but nests visible on these images did not correlate sufficiently well with ground data to be considered a viable basis for population monitoring. The 1997 census will serve as an important baseline, as Little Cayman is on the brink of explosive real estate development which is likely to have a severe impact on the island's natural resources over the next decade.

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Morgan, Jessica L., and Sarah E. Gergel. "Automated analysis of aerial photographs and potential for historic forest mapping." Canadian Journal of Forest Research 43, no. 8 (2013): 699–710. http://dx.doi.org/10.1139/cjfr-2012-0492.

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Historic information regarding forest status is essential to management and conservation. Manual interpretation of aerial photography has long been the standard for forest inventory; however, manual interpretation can be subjective, inconsistent, and labor-intensive. This research compares automated techniques with manual interpretation results. First, we used an automated process (called segmentation) to delineate homogeneous stands of forests (or objects), analogous to the goal of manually delineating of polygons. Second, we used classification and regression tree (CART) analysis to classify polygons into the forest and terrain schemes used in British Columbia. Most characteristics of objects created via segmentation were similar to manually delineated polygons, as >70% of attributes were statistically similar across local, polygon, and landscape-level comparisons. Using manual interpretations for comparative reference, automated classifications produced overall accuracies ranging from 62% to 86% with per-class accuracies ranging from 0% to 96%. Automated methods yielded classifications meeting provincial overlap accuracy targets and helped identify classifications most suited to automation. Automated procedures have potential for aiding swift utilization of extensive historical photography archives with several caveats for future consideration. While automated techniques may never replicate all aspects of forest inventory classification, automated techniques may be valuable in assisting different phases of the process.

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Kwa, Chunglin. "The Visual Grasp of the Fragmented Landscape." Historical Studies in the Natural Sciences 48, no. 2 (2018): 180–222. http://dx.doi.org/10.1525/hsns.2018.48.2.180.

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Between 1925 and 1980, landscape ecology underwent important changes through the gradual imposition of the view from above, through the uses of aerial photography. A new concept emerged, “the smallest unit of landscape,” also called ecotope and land unit, expressing a direct visual grasp of the landscape. This article compares the view from above as introduced and promoted by geographers Carl Troll and Isaak Zonneveld, with its (problematic) history vis-à-vis a school of ecology, i.e., plant sociology, led by Josias Braun-Blanquet and Reinhold Tüxen. This school’s internal struggles with balancing the physiognomic gaze (at the ground) and numerical methods are discussed. In comparison, the geographers based themselves on the mechanical objectivity of standardized aerial surveys, whereas the plant sociologists relied on their subjective expert judgment of plant recognition together with the structural objectivity of their numerical methods. An important communality of both schools was their inductive building of a landscape from its constituent landscape fragments. Landscape fragments were identified through abstraction and categorization, emanating from a taxonomical style of science.

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Quinlan, Kirsty, Dorian Moro, and Mark Lund. "Improving trapping success for rare species by targeting habitat types using remotely sensed data: a case study of the heath mouse (Pseudomys shortridgei) in Western Australia." Wildlife Research 31, no. 2 (2004): 219. http://dx.doi.org/10.1071/wr03031.

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The rare heath mouse (Pseudomys shortridgei) is the only rodent lacking a conservation program in Western Australia. Little is known about the habitat requirements of P. shortridgei in Western Australia, and there is a lack of trapping focus that could target specific habitat components that this species may use. The purpose of this study was to (1) relate the occurrence of this species to measurable components of its habitat; (2) incorporate habitat information into a GIS modelling system to identify other areas of potentially suitable habitat; and (3) test for the presence of P. shortridgei in predicted areas. In Lake Magenta Nature Reserve, 93% of P. shortridgei captures (14�of 15 mice) were associated with characteristics of a mixed laterite heath community representing 57 plant species and a dense structural layer up to 1.2 m. Aerial photography and satellite imagery were used to identify the occurrence of mixed laterite heath elsewhere within the reserve. Ground-truthing using pre-defined habitat criteria found that the best predictive model to define habitat was aerial photography. Trapping was undertaken in two areas of the reserve predicted by the modelling and resulted in the successful capture of the target species. This study demonstrates that aerial photography maps can provide a basis for focusing future trapping effort within reserves where P. shortrigei is likely to occur. The use of this GIS method provides a low-cost and simple method for improving the chances of locating additional populations of P. shortridgei in other nature reserves.

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Biggs, P. H. "Aerial tree volume functions for eucalypts in Western Australia." Canadian Journal of Forest Research 21, no. 12 (1991): 1823–28. http://dx.doi.org/10.1139/x91-251.

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Large-scale, fixed-base aerial photography is being used together with ground sampling in a major inventory of eucalypt forest in Western Australia. This paper describes the aerial tree volume functions derived for that inventory, covering species in the jarrah (Eucalyptusmarginata) forest. The equations, derived from ground measurements, predict gross bole volume from estimates of total height and vary with the site quality of the forest. They are used to predict volume from photomeasurements of total height that have been corrected for measurement error. The functions appear suitable for this forest type, although the volumes of veteran trees with severely damaged crowns are underestimated.

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Bisseggerand, M., and U. Heiniger. "Aerial photographs reveal chestnut-blight foci." Forest Pathology 24, no. 6-7 (1994): 419–23. http://dx.doi.org/10.1111/j.1439-0329.1994.tb00834.x.

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Miyamoto, Michiru, Kunihiko Yoshino, Toshihide Nagano, Tomoyasu Ishida, and Yohei Sato. "Use of balloon aerial photography for classification of Kushiro wetland vegetation, northeastern Japan." Wetlands 24, no. 3 (2004): 701–10. http://dx.doi.org/10.1672/0277-5212(2004)024[0701:uobapf]2.0.co;2.

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36

Fensham, R. J., J. C. McCosker, and M. J. Cox. "Estimating Clearance of Acacia-dominated Ecosystems in Central Queensland Using Land-system Mapping Data." Australian Journal of Botany 46, no. 2 (1998): 305. http://dx.doi.org/10.1071/bt96129.

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Preferential clearance of productive Acacia-dominated ecosystems was determined using digital land-system mapping and a 1994–1995 native vegetation remnant coverage from central Queensland. The previously mapped land systems are composed of complexes of land units, covering a range of productive potentials that are not individually mapped but defined according to their proportions within the land systems. Some land units were grouped into 11 ‘Acacia ecosystems’ composed of unique combinations of geology and vegetation dominated by brigalow (Acacia harpophylla F.Muell. ex Benth.), gidgee (A. cambagei R.T.Baker) or blackwood (A. argyrodendron Domin). Calculation of the remnant area of these Acacia ecosystems, assuming equal proportions of vegetation clearance of the land unit components within the land-system complexes (equal proportion calculation), was compared with a more accurate calculation based on interpretation of aerial photography (aerial-photograph calculation) data. The aerial photograph calculation of remnant area was 44% of the equal proportion calculation for brigalow on Tertiary clay and the ratio between these calculations was greater than 100% for only one Acacia ecosystem of relatively low production potential. The proportion of the remnant Acacia ecosystems relative to less productive ecosystems on tenures assigned to production (leasehold and freehold) was consistently lower than on other tenures. The use of mapping consisting of composite ecosystems with various production potentials for area-based assessment of vegetation clearance will overestimate the remnant areas of the relatively productive types unless a procedure such as that outlined here is used to correct for preferential clearance. This study provides near-complete and accurate data on the 1994–1995 status of Acacia ecosystems in central Queensland. Relative to their original area, values ranged from 6.8% for brigalow on Tertiary clay to 37.6% for gidgee–blackwood on alluvium.

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Udevitz, Mark S., Douglas M. Burn, and Marc A. Webber. "Estimation of walrus populations on sea ice with infrared imagery and aerial photography." Marine Mammal Science 24, no. 1 (2008): 57–70. http://dx.doi.org/10.1111/j.1748-7692.2007.00169.x.

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Arkin, Jeremy, Nicholas C. Coops, Txomin Hermosilla, Lori D. Daniels, and Andrew Plowright. "Integrated fire severity–land cover mapping using very-high-spatial-resolution aerial imagery and point clouds." International Journal of Wildland Fire 28, no. 11 (2019): 840. http://dx.doi.org/10.1071/wf19008.

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Fire severity mapping is conventionally accomplished through the interpretation of aerial photography or the analysis of moderate- to coarse-spatial-resolution pre- and post-fire satellite imagery. Although these methods are well established, there is a demand from both forest managers and fire scientists for higher-spatial-resolution fire severity maps. This study examines the utility of high-spatial-resolution post-fire imagery and digital aerial photogrammetric point clouds acquired from an unmanned aerial vehicle (UAV) to produce integrated fire severity–land cover maps. To accomplish this, a suite of spectral, structural and textural variables was extracted from the UAV-acquired data. Correlation-based feature selection was used to select subsets of variables to be included in random forest classifiers. These classifiers were then used to produce disturbance-based land cover maps at 5- and 1-m spatial resolutions. By analysing maps produced using different variables, the highest-performing spectral, structural and textural variables were identified. The maps were produced with high overall accuracies (5m, 89.5±1.4%; 1m, 85.4±1.5%), with the 1-m classification produced at slightly lower accuracies. This reduction was attributed to the inclusion of four additional classes, which increased the thematic detail enough to outweigh the differences in accuracy.

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Chung, Tabris Yik-To, Heysen Hei-Nam Ho, Henry Chun-Lok Tsui, and Brian Chin-Wing Kot. "First Unmanned Aerial Vehicle Observation of Epimeletic Behavior in Indo-Pacific Humpback Dolphins." Animals 12, no. 11 (2022): 1463. http://dx.doi.org/10.3390/ani12111463.

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Epimeletic behavior has been reported in various species of cetaceans and sometimes in wild populations during vessel-based surveys. Epimeletic behavior in cetaceans involves complex social interactions which have been described using observational and acoustic studies. The recent advances in unmanned aerial vehicle (UAV) technology allowed its application in wildlife research and frequently in cetaceans in conjunction with vessel-based surveys. This article is the first report of intraspecific epimeletic behavior of Indo-Pacific humpback dolphins (Sousa chinensis) in Hong Kong waters using a combination of UAV- and vessel-based photography. Using both techniques, we were able to observe and qualitative analyze the individual body condition, group behavior, and swimming pattern during the epimeletic event. This study highlighted that UAVs can be used to observe the complex social behaviors and interactions of cetaceans from the aerial angle while keeping a minimal level of disturbance to the animals. Aerial footage can also be quantitatively analyzed to provide further insights on the group behaviors of cetaceans. The application allows efficient assessment of health, behavior, and ecology of wild animals, offering valuable opportunities for researchers working on free-ranging populations.

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Maltamo, M., J. Malinen, P. Packalén, A. Suvanto, and J. Kangas. "Nonparametric estimation of stem volume using airborne laser scanning, aerial photography, and stand-register data." Canadian Journal of Forest Research 36, no. 2 (2006): 426–36. http://dx.doi.org/10.1139/x05-246.

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In forest management planning and forestry decision-making there is a continuous need for higher quality information on forest resources. The aim of this study was to improve the quality of forest resource information acquired by airborne laser scanning by combining it with aerial images and current stand-register data. A k-MSN (most similar neighbor) application was constructed for the prediction of the plot and stand volumes of standing trees. The application constructed used various data sources, including laser scanner data, aerial digital photographs, class variables describing a stand, and updated old stand volumes. The ability of these data sources to predict stem volume was tested together and separately. In the airborne laser scanner data based k-MSN application, characteristics of canopy quantiles were used as independent variables. The results show that with respect to individual plot and stand volume estimation approaches, the laser-based technique is a superior one. The results were improved further when other information sources were used together with the laser scanner data. Using a combination of laser scanner data, aerial images, and class variables (on the grounds of the current forest database) improved the root mean square error (RMSE) of the estimated plot volume by 15% (from 16% to 13%) as compared to using laser scanner data on their own. When the results were averaged at the stand level, the accuracy improved considerably, but the use of other information sources together with airborne laser scanner data did not further improve the results as it did at the plot level. The RMSE of stand volume was about 6% in all data combinations where airborne laser scanning information was used. One conclusion is that making use of additional available data sources together with laser material improves the reliability of plot volume estimates. As these additional data typically mean no extra material costs (since they are available in any case), making combined use of these data and laser scanner data improves the cost efficiency of a forest inventory.

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Lydersen, Jamie M., and Brandon M. Collins. "Change in Vegetation Patterns Over a Large Forested Landscape Based on Historical and Contemporary Aerial Photography." Ecosystems 21, no. 7 (2018): 1348–63. http://dx.doi.org/10.1007/s10021-018-0225-5.

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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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St-Onge, Benoît, Julien Jumelet, Mario Cobello, and Cédric Véga. "Measuring individual tree height using a combination of stereophotogrammetry and lidar." Canadian Journal of Forest Research 34, no. 10 (2004): 2122–30. http://dx.doi.org/10.1139/x04-093.

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Photogrammetric methods using parallaxes can be employed to measure tree heights on aerial photographs. Because it is often impossible to measure ground elevation near trees growing in dense forests, such height measurements remain prone to error. Our objective was to solve this problem by combining a stereomodel and a digital terrain model (DTM) produced by an airborne-scanning system that uses light detection and ranging (lidar). A stereopair of scanned aerial photographs was first registered to a lidar DTM. The elevation of the apex of 202 Thuja occidentalis (L.) individuals was measured by an observer on a digital photogrammetric workstation. The tree base elevations were read from the lidar DTM and subtracted from the corresponding apex elevations to calculate individual tree heights. These were then compared with the heights measured in the field. The average photo-lidar bias was 0.59 m, and the average deviation of 1.01 m decreased to 0.88 m when the bias was removed. It was demonstrated that the photographic clearness of the tree apices influences the height error, while the density of the lidar echoes under the forest canopy does not. Using this method, retrospective studies of changes in tree height become feasible by using archived aerial photographs and recent lidar DTMs.

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Boyd, W. Sean, and Joseph R. Jehl. "Estimating the Abundance of Eared Grebes on Mono Lake, California, by Aerial Photography." Colonial Waterbirds 21, no. 2 (1998): 236. http://dx.doi.org/10.2307/1521912.

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Ucar, Zennure, Pete Bettinger, Krista Merry, Jacek Siry, J. M. Bowker, and Ramazan Akbulut. "A comparison of two sampling approaches for assessing the urban forest canopy cover from aerial photography." Urban Forestry & Urban Greening 16 (2016): 221–30. http://dx.doi.org/10.1016/j.ufug.2016.03.001.

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Shanmugam, S., and M. Barnsley. "Quantifying landscape-ecological succession in a coastal dune system using sequential aerial photography and GIS." Journal of Coastal Conservation 8, no. 1 (2002): 61. http://dx.doi.org/10.1652/1400-0350(2002)008[0061:qlsiac]2.0.co;2.

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Shanmugam, S., and M. Barnsley. "Quantifying landscape-ecological succession in a coastal dune system using sequential aerial photography and GIS." Journal of Coastal Conservation 8, no. 1 (2002): 61–68. http://dx.doi.org/10.1007/bf02806585.

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Sorokin, A. I., Ye I. Kil'dyushevskiy, D. S. Gurevich, and B. I. Vanyukhin. "AERIAL PHOTOGRAPHIC STUDIES OF THE MARINE ECOLOGY OF THE WHITE SEA." Mapping Sciences and Remote Sensing 26, no. 2 (1989): 116–25. http://dx.doi.org/10.1080/07493878.1989.10641752.

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Rhodes, Edward C., Humberto L. Perotto-Baldivieso, Matthew C. Reeves, and Luciano A. Gonzalez. "Perspectives on the Special Issue for Applications of Remote Sensing for Livestock and Grazingland Management." Remote Sensing 14, no. 8 (2022): 1882. http://dx.doi.org/10.3390/rs14081882.

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The use of geospatial sciences and technologies for the management of grazinglands has fostered a plethora of applications related to ecology, wildlife, vegetation science, forage productivity and quality, and animal husbandry. Some of the earliest use of remote sensing dates to the proliferation of aerial photography in the 1930s. Today, remote sensing using satellite imagery, global navigation satellite systems (GNSS), and internet-connected devices and sensors allow for real- and near real-time modeling and observation of grazingland resources. In this special issue of Remote Sensing, we introduce nine original publications focusing on varying aspects of grazingland management, such as animal health and telemetry, climate change, soil moisture, herbaceous biomass, and vegetation phenology. The work in this issue spans a diverse range of scale from satellite to unmanned aerial systems imagery, as well as ground-based measurements from mounted cameras, telemetry devices, and datalogging devices. Remote sensing-based technologies continue to evolve, allowing us to address critical issues facing grazingland management such as climate change, restoration, forage abundance and quality, and animal behavior, production, and welfare.

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Thomas, Don. "Needed: less counting of caribou and more ecology." Rangifer 18, no. 5 (1998): 15. http://dx.doi.org/10.7557/2.18.5.1394.

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Most aerial surveys designed to estimate numbers of caribou (Rangifer tarandus) lack clear objectives, are inaccurate and imprecise, lack application, and often are doubted by the public. Sources of error in surveys are bias (inaccuracy) and sampling error (imprecision) caused largely by sampling units (strips, secrions of strips, quadrats, or photographs) being inappropriate for highly variable group sizes and distributions. Many visual strip surveys of caribou on calving grounds were inaccurate by 136-374%. Photographic surveys of calving caribou are more accurate but usually have coefficients of variation (CV) of 20-40%, whereas a CV of about 15% is required to detect a 50% change in population size between surveys. Extrapolation of such counts to population size produces unacceptable accuracy and precision. Consequently, no conclusions can be made about changes in population numbers between or among surveys because even large natural fluctuations fall within confidence limits. These problems combined with difficulties of managing caribou populations in remote areas of northern Canada indicate that scarce funds may be better allocated to ecological studies.

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