Dissertations / Theses: 'Habitat mapping'

1

Stevens, Tim, and n/a. "Mapping Benthic Habitats for Representation in Marine Protected Areas." Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040303.124815.

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Virtually all marine conservation planning and management models in place or proposed have in common the need for improved scientific rigour in identifying and characterising the marine habitats encompassed. An emerging central theme in the last few years has been the concept of representativeness, or representative systems of Marine Protected Areas (MPAs). The habitat classification and mapping needed to incorporate considerations of representativeness into MPA planning must logically be carried out at the same scale at which management occurs. Management of highly protected areas occurs almost exclusively at local scales or finer, independent of the reservation model or philosophy employed. Moreton Bay, on Australias east coast, was selected for studies at the local scale to map and classify macrobenthic habitats. In a site scale (1 km) trial for the major habitat classification study, remote underwater videography was used to map and characterise an unusual assemblage of epibenthic invertebrates on soft sediments. The assemblage included congregations of the comatulid crinoid Zygometra cf. Z. microdiscus (Bell) at densities up to 0.88 individuals.m-2, comparable to those found in coral reef habitats. There was no correlation between the distribution of this species and commonly used abiotic surrogates depth (6 18 m), sediment composition and residual current. This site scale trial is the first quantitative assessment of crinoid density and distribution in shallow water soft-sediment environments. The high densities found are significant in terms of the generally accepted picture of shallow-water crinoids as essentially reefal fauna. The findings highlight the conservation benefits of an inclusive approach to marine habitat survey and mapping. Assemblages such as the one described, although they may be of scientific and ecological significance, would have been overlooked by common approaches to marine conservation planning which emphasise highly productive or aesthetically appealing habitats. Most habitat mapping studies rely solely or in part on abiotic surrogates for patterns of biodiversity. The utility of abiotic variables in predicting biological distributions at the local scale (10 km) was tested. Habitat classifications of the same set of 41 sites based on 6 abiotic variables and abundances of 89 taxa and bioturbation indicators were compared using correlation, regression and ordination analyses. The concepts of false homogeneity and false heterogeneity were defined to describe types of errors associated with using abiotic surrogates to construct habitat maps. The best prediction by abiotic surrogates explained less than 30% of the pattern of biological similarity. Errors of false homogeneity were between 20 and 62%, depending on the methods of estimation. Predictive capability of abiotic surrogates at the taxon level was poor, with only 6% of taxon / surrogate correlations significant. These results have implications for the widespread use of abiotic surrogates in marine habitat mapping to plan for, or assess, representation in Marine Protected Areas. Abiotic factors did not discriminate sufficiently between different soft bottom communities to be a reliable basis for mapping. Habitat mapping for the design of Marine Protected Areas is critically affected by the scale of the source information. The relationship between biological similarity of macrobenthos and the distance between sites was investigated at both site and local scales, and for separate biotic groups. There was a significant negative correlation between similarity and distance, in that sites further apart were less similar than sites close together. The relationship, although significant, was quite weak at the site scale. Rank correlograms showed that similarity was high at scales of 10 km or less, and declined markedly with increasing distance. There was evidence of patchiness in the distributions of some biotic groups, especially seagrass and anthozoans, at scales less than 16 km. In other biotic groups there was an essentially monotonic decline in similarity with distance. The spatial agglomeration approach to habitat mapping was valid in the study area. Site spacing of less than 10 km was necessary to capture important components of biological similarity. Site spacing of less than 2.5 km did not appear to be warranted. Macrobenthic habitat types were classified and mapped at 78 sites spaced 5 km apart. The area mapped was about 2,400 km2 and extended from estuarine shallow subtidal waters to offshore areas to the 50 m isobath. Nine habitat types were recognised, with only one on hard substrate. The habitat mapping characterised several habitat types not previously described in the area and located deepwater algal and soft coral reefs not previously reported. Seagrass beds were encountered in several locations where their occurrence was either unknown or had not previously been quantified. The representation of the derived habitat types within an existing marine protected area was assessed. Only two habitat types were represented in highly protected zones, with less than 3% of each included The study represents the most spatially comprehensive survey of epibenthos undertaken in Moreton Bay, with over 40,000 m2 surveyed. Derived habitat maps provide a robust basis for inclusion of representative examples of all habitat types in marine protected area planning in and adjacent to Moreton Bay. The utility of video data to conduct a low-cost habitat survey over a comparatively large area was also demonstrated. The method used has potentially wide application for the survey and design of marine protected areas.

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2

Stevens, Tim. "Mapping Benthic Habitats for Representation in Marine Protected Areas." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367557.

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Abstract:

Virtually all marine conservation planning and management models in place or proposed have in common the need for improved scientific rigour in identifying and characterising the marine habitats encompassed. An emerging central theme in the last few years has been the concept of representativeness, or representative systems of Marine Protected Areas (MPAs). The habitat classification and mapping needed to incorporate considerations of representativeness into MPA planning must logically be carried out at the same scale at which management occurs. Management of highly protected areas occurs almost exclusively at local scales or finer, independent of the reservation model or philosophy employed. Moreton Bay, on Australia’s east coast, was selected for studies at the local scale to map and classify macrobenthic habitats. In a site scale (1 km) trial for the major habitat classification study, remote underwater videography was used to map and characterise an unusual assemblage of epibenthic invertebrates on soft sediments. The assemblage included congregations of the comatulid crinoid Zygometra cf. Z. microdiscus (Bell) at densities up to 0.88 individuals.m-2, comparable to those found in coral reef habitats. There was no correlation between the distribution of this species and commonly used abiotic surrogates depth (6 – 18 m), sediment composition and residual current. This site scale trial is the first quantitative assessment of crinoid density and distribution in shallow water soft-sediment environments. The high densities found are significant in terms of the generally accepted picture of shallow-water crinoids as essentially reefal fauna. The findings highlight the conservation benefits of an inclusive approach to marine habitat survey and mapping. Assemblages such as the one described, although they may be of scientific and ecological significance, would have been overlooked by common approaches to marine conservation planning which emphasise highly productive or aesthetically appealing habitats. Most habitat mapping studies rely solely or in part on abiotic surrogates for patterns of biodiversity. The utility of abiotic variables in predicting biological distributions at the local scale (10 km) was tested. Habitat classifications of the same set of 41 sites based on 6 abiotic variables and abundances of 89 taxa and bioturbation indicators were compared using correlation, regression and ordination analyses. The concepts of false homogeneity and false heterogeneity were defined to describe types of errors associated with using abiotic surrogates to construct habitat maps. The best prediction by abiotic surrogates explained less than 30% of the pattern of biological similarity. Errors of false homogeneity were between 20 and 62%, depending on the methods of estimation. Predictive capability of abiotic surrogates at the taxon level was poor, with only 6% of taxon / surrogate correlations significant. These results have implications for the widespread use of abiotic surrogates in marine habitat mapping to plan for, or assess, representation in Marine Protected Areas. Abiotic factors did not discriminate sufficiently between different soft bottom communities to be a reliable basis for mapping. Habitat mapping for the design of Marine Protected Areas is critically affected by the scale of the source information. The relationship between biological similarity of macrobenthos and the distance between sites was investigated at both site and local scales, and for separate biotic groups. There was a significant negative correlation between similarity and distance, in that sites further apart were less similar than sites close together. The relationship, although significant, was quite weak at the site scale. Rank correlograms showed that similarity was high at scales of 10 km or less, and declined markedly with increasing distance. There was evidence of patchiness in the distributions of some biotic groups, especially seagrass and anthozoans, at scales less than 16 km. In other biotic groups there was an essentially monotonic decline in similarity with distance. The spatial agglomeration approach to habitat mapping was valid in the study area. Site spacing of less than 10 km was necessary to capture important components of biological similarity. Site spacing of less than 2.5 km did not appear to be warranted. Macrobenthic habitat types were classified and mapped at 78 sites spaced 5 km apart. The area mapped was about 2,400 km2 and extended from estuarine shallow subtidal waters to offshore areas to the 50 m isobath. Nine habitat types were recognised, with only one on hard substrate. The habitat mapping characterised several habitat types not previously described in the area and located deepwater algal and soft coral reefs not previously reported. Seagrass beds were encountered in several locations where their occurrence was either unknown or had not previously been quantified. The representation of the derived habitat types within an existing marine protected area was assessed. Only two habitat types were represented in highly protected zones, with less than 3% of each included The study represents the most spatially comprehensive survey of epibenthos undertaken in Moreton Bay, with over 40,000 m2 surveyed. Derived habitat maps provide a robust basis for inclusion of representative examples of all habitat types in marine protected area planning in and adjacent to Moreton Bay. The utility of video data to conduct a low-cost habitat survey over a comparatively large area was also demonstrated. The method used has potentially wide application for the survey and design of marine protected areas.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
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3

Flaherty, Silvia Susana. "Red squirrel habitat mapping using remote sensing." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/7607.

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The native Eurasian red squirrel is considered endangered in the UK and is under strict legal protection. Long-term management of its habitat is a key goal of the UK conservation strategy. Current selection criteria of reserves and subsequent management mainly consider species composition and food availability. However, there exists a critical gap in understanding and quantifying the relationship between squirrel abundance, their habitat use and forest structural characteristics. This has partly resulted from the limited availability of structural data along with cost-efficient data collection methods. This study investigated the relationship between squirrel feeding activity and structural characteristics of Scots pine forests. Field data were collected from two study areas: Abernethy and Aberfoyle Forests. Canopy closure, diameter at breast height, height and number of trees were measured in 56 plots. Abundance of squirrel feeding signs was used as an index of habitat use. A GLM was used to model the response of cones stripped by squirrels in relation to the field collected structural variables. Results show that forest structural characteristics are significant predictors of feeding sign presence, with canopy closure, number of trees and tree height explaining 43% of the variation in stripped cones. The GLM was also implemented using LiDAR data to assess at wider scales the number of cones stripped by squirrels. The use of remote sensing -in particular Light Detection and Ranging (LiDAR) - enables cost efficient assessments of forest structure at large scales and can be used to retrieve the three variables explored in this study; canopy cover, tree height and number of trees, that relate to red squirrel feeding behaviour. Correlation between field-predicted and LiDAR-predicted number of stripped cones was performed to assess LiDAR-based model performance. LiDAR data acquired at Aberfoyle and Abernethy Forests had different characteristics (in particular pulse density), which influences the accuracy of LiDAR derived metrics. Therefore correlations between field predicted and LiDAR predicted number of cones (LSC) were assessed for each study area separately. Strong correlations (rs=0.59 for Abernethy and 0.54 for Aberfoyle) suggest that LiDAR-based model performed relatively well over the study areas. The LiDAR-based model was not expected to provide absolute numbers of cones stripped by squirrels but a relative measure of habitat use. This can be interpreted as different levels of habitat suitability for red squirrels. LiDAR-based GLM maps were classified into three levels of suitability: unsuitable (LSC = 0), Low (LSC < 10) and Medium to High Suitability (LSC >=10). These thresholds were defined based on expert knowledge. Such a classification of habitat suitability allows for further differentiation of habitat quality for red squirrels and therefore for a refined estimation of the carrying capacity that was used to inform population viability analysis (PVA) at Abernethy Forest. PVA assists the evaluation of the probability of a species population to become extinct over a specified period of time, given a set of data on environmental conditions and species characteristics. In this study, two scenarios were modelled in a PVA package (VORTEX). For the first scenario (Basic) carrying capacity was calculated for the whole forest, while for the second scenario (LiDAR) only Medium-to-High suitable patches were considered. Results suggest a higher probability of extinction for the LiDAR scenario (74%) than for the Basic scenario (55%). Overall the findings of this study highlight 1) the importance of considering forest structure when managing habitat for squirrel conservation and 2) the usefulness of LiDAR remote sensing as a tool to assist red squirrel, and potentially other species, habitat management.

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4

McGonigle, Chris. "Mapping benthic habitat using acoustic remote sensing." Thesis, University of Ulster, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.551582.

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Backscatter imagery from multibeam echosounders (MBES) is increasingly used for benthic habitat mapping. This research explores MBES backscatter classification using QTC-Multiview on data from Stanton Banks (UK) and Cashes Ledge (USA). Image-processing algorithms are used to extract values from samples of backscatter data, which are reduced by principal components analysis and are objectively clustered. This process is initially evaluated using 2005 data from Stanton Banks and compared with ground-truth data to determine their biological validity. Low-levels of agreement are observed between acoustic class and ground- truth data «35%); video is determined to be the most spatially appropriate method for comparison. Subsequently, the area was resurveyed in 2006 using the same MBES with different operational parameters, acquiring low- and high-density data coverage. Percentage agreement between classifications was 78%, determined to be due to operational parameters as opposed to environmental change. Agreement with ground truth data improved from 71 % to 77% with increased data density. In 2008, a 2 km2 area was resurveyed at two different orientations and vessel speeds within the same 24 hr period. Classification revealed 53% similarity at 4 rns-1 and 49% at 2 rns-1 from opposing orientations. The same orientations surveyed at different speeds were between 68% (k=0.583) and 53% (k=0.384) similar. These results suggest that both orientation and speed are significant considerations in image-based classification. Finally, the significance of water-column biomass in backscatter classification was examined at Cashes Ledge using MBES data from kelp beds. Two approaches were examined for detecting the presence of macrophytes; image-based and manual picking. Comparison with video data revealed comparable success, with both methods most successful at predicting Laminaria sp. (77.3%-82.6% correct) in shallow water «30m). This research demonstrates the significance of MBES backscatter and image-based classification as potential tools for the emergent discipline of benthic habitat mapping.

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5

Parnum, Iain Michael. "Benthic habitat mapping using multibeam sonar systems." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/1131.

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The aim of this study was to develop and examine the use of backscatter data collected with multibeam sonar (MBS) systems for benthic habitat mapping. Backscatter data were collected from six sites around the Australian coastal zone using the Reson SeaBat 8125 MBS system operating at 455 kHz. Benthic habitats surveyed in this study included: seagrass meadows, rhodolith beds, coral reef, rock, gravel, sand, muddy sand, and mixtures of those habitats. Methods for processing MBS backscatter data were developed for the Coastal Water Habitat Mapping (CWHM) project by a team from the Centre for Marine Science and Technology (CMST). The CMST algorithm calculates the seafloor backscatter strength derived from the peak and integral (or average) intensity of backscattered signals for each beam. The seafloor backscatter strength estimated from the mean value of the integral backscatter intensity was shown in this study to provide an accurate measurement of the actual backscatter strength of the seafloor and its angular dependence. However, the seafloor backscatter strength derived from the peak intensity was found to be overestimated when the sonar insonification area is significantly smaller than the footprint of receive beams, which occurs primarily at oblique angles. The angular dependence of the mean backscatter strength showed distinct differences between hard rough substrates (such as rock and coral reef), seagrass, coarse sediments and fine sediments. The highest backscatter strength was observed not only for the hard and rough substrate, but also for marine vegetation, such as rhodolith and seagrass. The main difference in acoustic backscatter from the different habitats was the mean level, or angle-average backscatter strength. However, additional information can also be obtained from the slope of the angular dependence of backscatter strength.It was shown that the distribution of the backscatter. The shape parameter was shown to relate to the ratio of the insonification area (which can be interpreted as an elementary scattering cell) to the footprint size rather than to the angular dependence of backscatter strength. When this ratio is less than 5, the gamma shape parameter is very similar for different habitats and is nearly linearly proportional to the ratio. Above a ratio of 5, the gamma shape parameter is not significantly dependent on the ratio and there is a noticeable difference in this parameter between different seafloor types. A new approach to producing images of backscatter properties, introduced and referred to as the angle cube method, was developed. The angle cube method uses spatial interpolation to construct a three-dimensional array of backscatter data that is a function of X-Y coordinates and the incidence angle. This allows the spatial visualisation of backscatter properties to be free from artefacts of the angular dependence and provides satisfactory estimates of the backscatter characteristics.Using the angle-average backscatter strength and slope of the angular dependence, derived by the angle cube method, in addition to seafloor terrain parameters, habitat probability and classification maps were produced to show distributions of sand, marine vegetation (e.g. seagrass and rhodolith) and hard substrate (e.g. coral and bedrock) for five different survey areas. Ultimately, this study demonstrated that the combination of high-resolution bathymetry and backscatter strength data, as collected by MBS, is an efficient and cost-effective tool for benthic habitat mapping in costal zones.

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6

Parnum, Iain Michael. "Benthic habitat mapping using multibeam sonar systems." Curtin University of Technology, Dept. of Imaging and Applied Physics, Centre for Marine Science and Technology, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=18584.

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The aim of this study was to develop and examine the use of backscatter data collected with multibeam sonar (MBS) systems for benthic habitat mapping. Backscatter data were collected from six sites around the Australian coastal zone using the Reson SeaBat 8125 MBS system operating at 455 kHz. Benthic habitats surveyed in this study included: seagrass meadows, rhodolith beds, coral reef, rock, gravel, sand, muddy sand, and mixtures of those habitats. Methods for processing MBS backscatter data were developed for the Coastal Water Habitat Mapping (CWHM) project by a team from the Centre for Marine Science and Technology (CMST). The CMST algorithm calculates the seafloor backscatter strength derived from the peak and integral (or average) intensity of backscattered signals for each beam. The seafloor backscatter strength estimated from the mean value of the integral backscatter intensity was shown in this study to provide an accurate measurement of the actual backscatter strength of the seafloor and its angular dependence. However, the seafloor backscatter strength derived from the peak intensity was found to be overestimated when the sonar insonification area is significantly smaller than the footprint of receive beams, which occurs primarily at oblique angles. The angular dependence of the mean backscatter strength showed distinct differences between hard rough substrates (such as rock and coral reef), seagrass, coarse sediments and fine sediments. The highest backscatter strength was observed not only for the hard and rough substrate, but also for marine vegetation, such as rhodolith and seagrass. The main difference in acoustic backscatter from the different habitats was the mean level, or angle-average backscatter strength. However, additional information can also be obtained from the slope of the angular dependence of backscatter strength.
It was shown that the distribution of the backscatter. The shape parameter was shown to relate to the ratio of the insonification area (which can be interpreted as an elementary scattering cell) to the footprint size rather than to the angular dependence of backscatter strength. When this ratio is less than 5, the gamma shape parameter is very similar for different habitats and is nearly linearly proportional to the ratio. Above a ratio of 5, the gamma shape parameter is not significantly dependent on the ratio and there is a noticeable difference in this parameter between different seafloor types. A new approach to producing images of backscatter properties, introduced and referred to as the angle cube method, was developed. The angle cube method uses spatial interpolation to construct a three-dimensional array of backscatter data that is a function of X-Y coordinates and the incidence angle. This allows the spatial visualisation of backscatter properties to be free from artefacts of the angular dependence and provides satisfactory estimates of the backscatter characteristics.
Using the angle-average backscatter strength and slope of the angular dependence, derived by the angle cube method, in addition to seafloor terrain parameters, habitat probability and classification maps were produced to show distributions of sand, marine vegetation (e.g. seagrass and rhodolith) and hard substrate (e.g. coral and bedrock) for five different survey areas. Ultimately, this study demonstrated that the combination of high-resolution bathymetry and backscatter strength data, as collected by MBS, is an efficient and cost-effective tool for benthic habitat mapping in costal zones.

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Jones, Gwawr Angharad. "Coastal habitat mapping and monitoring utilising remote sensing." Thesis, Aberystwyth University, 2017. http://hdl.handle.net/2160/cfb598d7-9bb7-44a7-8725-bcf13d81657b.

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Coastal habitats are highly sensitive to change and highly diverse. Degrading environmental conditions have led to a global decline in biodiversity through loss, modification and fragmentation of habitats, triggering an increased effort to conserve these ecosystems. Remote sensing is important tool for filling in critical information gaps for monitoring habitats, yet significant barriers exist for operational use within the ecological and conservation communities. Reporting on both extent and condition of habitats are critical to fulfil policy requirements, specifically the ECs Habitat’s Directive. This study focuses on the use of Very High Resolution (VHR) optical imagery for retrieving parameters to identifyassociations that can separate habitat boundaries for extent mapping down to species level for indicators of condition, with a focus on operational use. The Earth Observation Data for Habitat Monitoring (EODHaM) system was implemented using Worldview-2 data from two periods (July and September), in situ data and local ecological knowledge for two sites in Wales, Kenfig Burrows SAC and Castlemartin SSSI. The system utilises the Food and Agricultural Organisation’s (FAO) Land Cover Classification System (LCCS) but translations between land cover and habitat schemes are not straight forward and need special consideration that are likely to be site specific. Limitations within therule-based method of the EODHaM system were identified and therefore augmented with machine learning based classification algorithms creating a hybrid method of classification generating accurate (>80% overall accuracy) baseline maps with a more automated and repeatable method. Quantitative methods of validation traditionally used within the remote sensing community do not consider spatial aspects of maps. Therefore, qualitative assessments carried out in the field were used in addition to error matrices, overall accuracy and the kappa coefficient. This required input from ecologists and site specialists, enhancing communication and understanding between the different communities. Generating baseline maps required significant amount of training data and updating baselines through change detection methods is recommended for monitoring. An automated, novel map-to-image change detection was therefore implemented. Natural and anthropogenic changes were successfully detected from Worldview-2 and Sentinel-2 data at Kenfig Burrows. An innovative component of this research was the development of methods, which were demonstrated to be transferable between both sites and increased understanding between remote sensing scientist and ecologist. Through this approach, a more operational method for monitoring site specific habitats through satellite data is proposed, with direct benefits for conservation, environment and policy.

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Christensen, Ole. "SUSHIMAP (Survey strategy and methodology for marine habitat mapping)." Doctoral thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1916.

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Bathymetrical mapping performed using multibeam sonar systems is widely used in marine science and for habitat mapping. The incoherent part of the multibeam data, the backscatter data, is less commonly used. Automatic classification of processed backscatter has a correlates well with three sediment classes, defined as fine-(clay-silt), medium- (sand) and coarse- (gravel–till) grained substrates. This relation is used directly as a theme in a modified habitat classification scheme, while a more detailed substrate classification is incorporated as another theme. This theme requires a manual interpretation and comprehensive knowledge of the substrate. This can partly be obtained by a newly developed technique using the backscatter strength plotted against the grazing angle. These plots make it possible to determine the critical angle and thereby calculate the compressional acoustic speed in seabed sediments. Marching a theoretical modeled backscatter curve to the measured backscatter strength at lower grazing angles provides estimates of four additional geoacoustic parameters.

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McDermid, Gregory. "Remote Sensing for Large-Area, Multi-Jurisdictional Habitat Mapping." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/977.

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A framework designed to guide the effective use of remote sensing in large-area, multi-jurisdictional habitat mapping studies has been developed. Based on hierarchy theory and the remote sensing scene model, the approach advocates (i) identifying the key physical attributes operating on the landscape; (ii) selecting a series of suitable remote sensing data whose spatial, spectral, radiometric, and temporal characteristics correspond to the attributes of interest; and (iii) applying an intelligent succession of scale-sensitive data processing techniques that are capable of delivering the desired information. The approach differs substantially from the single-map, classification-based strategies that have largely dominated the wildlife literature, and is designed to deliver a sophisticated, multi-layer information base that is capable of supporting a variety of management objectives. The framework was implemented in the creation of a multi-layer database composed of land cover, crown closure, species composition, and leaf area index (LAI) phenology over more than 100,000 km² in west-central Alberta. Generated through a combination of object-oriented classification, conventional regression, and generalized linear models, the products represent a high-quality, flexible information base constructed over an exceptionally challenging multi-jurisdictional environment. A quantitative comparison with two alternative large-area information sources—the Alberta Vegetation Inventory and a conventional classification-based land-cover map—showed that the thesis database had the highest map quality and was best capable of explaining both individual—and population-level resource selection by grizzly bears.

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Puestow, Thomas. "Mapping of salmon habitat parameters using digital airborne imagery." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0005/MQ42428.pdf.

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May, Cassandra J. "Habitat Mapping and Predator-Prey Dynamics in Ohio Resevoirs." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1364461349.

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Thackrah, G. "Habitat mapping and biodiversity monitoring using earth observation and GIS." Thesis, Swansea University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639175.

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Areas of high conservation value in the UK often have a legal requirement for some form of regular monitoring of their status. This thesis investigates the use of methods in Earth Observation to achieve this both reliably and faster than land based approaches. This is done through the use of a case study in south Wales, Kenfig National Nature Reserve. The site is a candidate Special Area for Conservation under the European Union's Habitats Directive. This is due to the presence of the fen orchid, Liparis loeselii, and petalwort, Petalophyllum ralfsii. Use is made of data from two principal airborne multispectral sensors, the Compact Airborne Spectrographic Imager (CASI) and the Airborne Thematic Mapper (ATM) as well as a Light Detection and Ranging (LIDAR) instrument. Simple methods of EO data processing are used to classify these data and produce accurate maps of habitat in an area of high conservation value. Habitats with similar spectral properties are hard to classify in this way. Methods of data fusion and information aggregation were thus applied to assist in the identification of habitats inaccurately identified with the simpler methods of classification. These are shown to produce more robust results. Furthermore, ancillary data, in the form of elevation information, may also be used to refine the classification process again. Using a method of information aggregation that allows constituent sources to be differentially weighted in light of a priori knowledge regarding classifier accuracy, a robust classification is produced. It is concluded that the data fusion approaches allow more robust classification products to be supplied to the end users of the data, the managers of sites of conservation interest such as Kenfig NNR. The availability of such approaches in commonly available computing environments is currently limited; it is therefore suggested that they be made more widely available by suppliers of GIS technology to conservation organisations.

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Lucas, Joseph S. "CONSERVATION LIMNOGEOLOGY AND BENTHIC HABITAT MAPPING IN CENTRAL LAKE TANGANYIKA (TANZANIA)." UKnowledge, 2018. https://uknowledge.uky.edu/ees_etds/60.

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Small scale protected zones are valuable for helping the health and productivity of fisheries at Lake Tanganyika (East Africa). Spatial placement of protected areas relies on accurate maps of benthic habitats, consisting of detailed bathymetry data and information on lake-floor substrates. This information is unknown for most of Lake Tanganyika. Fish diversity is known to correlate with rocky substrates in ≤ 30 m water depth, which provide spawning grounds for littoral and pelagic species. These benthic habitats form important targets for protected areas, if they can be precisely located. At the NMVA, echosounding defined the position of the 30-m isobath and side-scan sonar successfully discriminated among crystalline basement, CaCO3-cemented sandstones, mixed sediment, and shell bed substrates. Total area encompassed from the shoreline to 30 m water depth is ~21 km2 and the distance to the 30-m isobath varies with proximity to deltas and rift-related faults. Total benthic area defined by crystalline basement is ~1.6 km2, whereas the total area of CaCO3-cemented sandstone is 0.2 km2. Crystalline basement was present in all water depths (0-30 m), whereas CaCO3-cemented sandstones were usually encountered in water ≤ 5 m deep. Spatial organization of rocky substrates is chiefly controlled by basin structure and lake level history.

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Tomlinson, Jaime L. "Mapping and sampling the subtidal habitat of Sabellaria vulgaris in Delaware Bay." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 3.38 Mb., 145 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1432289.

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Sanchez, Hernandez Carolina. "Land cover mapping of one specific protected habitat under the requirements of the European Union Habitats Directive using remote sensing." Thesis, Kingston University, 2006. http://eprints.kingston.ac.uk/20380/.

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Habitat loss is considered to be one of the greatest challenges currently facing society. An important part of the European Union's (EU) response to this problem is the Habitats Directive, the main aim of which is to protect biodiversity through the conservation and protection of natural habitats. Consequently, accurate mapping of specific habitats is of high importance in order to monitor ecosystem changes. Within this context, remote sensing has enormous potential as a source of land cover information which has been used widely for land cover mapping. In many instances this land cover mapping is only concerned with one particular habitat. However, in standard classification analysis, training data for all of the land cover classes contained in the area is typically required which means a wasteful use of resources. This thesis aims to address these issues by investigating advanced classification methods that focus on the accurate mapping of one specific protected habitat. The data used for this purpose is a Landsat ETM+ image of East Anglia, UK, acquired in June 2000 and ground truth data in the form of aerial photography. The habitat of interest chosen for this investigation is fens, a habitat protected by the EU Habitats Directive, whose diverse and dynamic nature is a particular challenge for its mapping and monitoring. A second protected habitat, saltmarshes, will be used for comparison purposes in order to determine any bias within the results. The methods considered to map the selected habitat consist of binary classifiers and one class classifiers. The binary classifiers chosen were Support Vector Machines (SVMs) and Decision Trees (DTs) which are two new methods very recently applied to land cover classification and remote sensing research. They are still very much the focus of current research for multiclass classification. In this thesis they are used in its binary form to classify the class of interest against. all the other classes. Both classifiers perform very well when compared with a classic parametric Maximum Likelihood Classification (MLC). Narrowing down the idea of classifying just one habitat of interest, one-class classifiers are put to the test. They have been explored in pattern recognition research but not yet within remote sensing image classification and land cover mapping. Specifically, the Support Vector Data Description (SYDD) classifier is considered particularly suitable for land cover classification as it is based upon the basis of SVMs which have already been applied in this area with success. When the results of the SYDD classification are compared against those obtained by the other classifiers these show an improvement in overall classification and a reduction in the errors of commission. Furthermore, another method is also put to the test to improve the accuracy of the classification of the class of interest. This method is the ensemble of classifiers, which in many research studies within pattern recognition has proven to improve accuracy of single classifiers. The results in this thesis also show an improvement in accuracy, although further investigation is needed. In conclusion, DT, SVM and SYDD classification methods offer clear advantages over standard classification analysis when concentrating on the classification and mapping of a particular habitat. All three classifiers obtained higher accuracies than the ML classifier with the use of significantly less training data. Furthermore, in the case of one-class classification only data from the class of interest was needed. Also in both binary and one-class classification approaches the attention was focused on separating the class of interest from all the other classes and therefore training efficiency was bigger than in a standard multiclass classification where efforts are directly to achieve a high overall accuracy. All three methods were found to be highly suitable for classifying and mapping a specific habitat and its application should be considered in future work involving the accurate mapping of protected habitats.

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Walters, Sarah Lyle. "Mapping Tampa Bay Cynoscion nebulosus Spawning Habitat Using Passive Acoustic Surveys." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001318.

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Wallace, Cynthia S. A. "Extracting temporal and spatial information from remotely sensed data for mapping wildlife habitat." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280220.

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The research accomplished in this dissertation used both mathematical and statistical techniques to extract and evaluate measures of landscape temporal dynamics and spatial structure from remotely sensed data for the purpose of mapping wildlife habitat. By coupling the landscape measures gleaned from the remotely sensed data with various sets of animal sightings and population data, effective models of habitat preference were created. Measures of temporal dynamics of vegetation greenness as measured by National Oceanographic and Atmospheric Administration's Advanced Very High Resolution Radiometer (AVHRR) satellite were used to effectively characterize and map season specific habitat of the Sonoran pronghorn antelope, as well as produce preliminary models of potential yellow-billed cuckoo habitat in Arizona. Various measures that capture different aspects of the temporal dynamics of the landscape were derived from AVHRR Normalized Difference Vegetation Index composite data using three main classes of calculations: basic statistics, standardized principal components analysis, and Fourier analysis. Pronghorn habitat models based on the AVHRR measures correspond visually and statistically to GIS-based models produced using data that represent detailed knowledge of ground-condition. Measures of temporal dynamics also revealed statistically significant correlations with annual estimates of elk population in selected Arizona Game Management Units, suggesting elk respond to regional environmental changes that can be measured using satellite data. Such relationships, once verified and established, can be used to help indirectly monitor the population. Measures of landscape spatial structure derived from IKONOS high spatial resolution (1-m) satellite data using geostatistics effectively map details of Sonoran pronghorn antelope habitat. Local estimates of the nugget, sill, and range variogram parameters calculated within 25 x 25-meter image windows describe the spatial autocorrelation of the image, permitting classification of all pixels into coherent units whose signature graphs exhibit a classic variogram shape. The variogram parameters captured in these signatures have been shown in previous studies to discriminate between different species-specific vegetation associations. The synoptic view of the landscape provided by satellite data can inform resource management efforts. The ability to characterize the spatial structure and temporal dynamics of habitat using repeatable remote sensing data allows closer monitoring of the relationship between a species and its landscape.

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Baglivio, Eileen Ann. "COMPARING THE DEMOGRAPHICS OF TWO STEELHEAD POPULATIONS AND THEIR HABITAT CHARACTERISTICS." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/719.

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Currently, little is known about the demographics of the Oncorhynchus mykiss irideus, or steelhead trout, populations in San Luis Obispo County. Specifically, demographic information including length, age, and condition when first leaving a watershed for the open ocean is lacking. This thesis takes a closer look at a biological and environmental data collected by the California Department of Fish and Game Central Coast Steelhead and Coho Salmon project under the direction of Associate Biologist Jennifer Nelson. The main goal of this thesis is to analyze demographic and habitat data from the steelhead populations of two northern San Luis Obispo county coastal streams, San Simeon and Santa Rosa Creeks. Habitat mapping surveys were conducted on each stream in order to identify suitable habitat for various steelhead life stages. The data generated from the habitat mapping surveys was compared between the two creeks over the two different survey years (1993 and 2005). The results of these surveys showed that habitat types have changed on San Simeon Creek between survey years while Santa Rosa Creek appeared to remain the same. Biological inventory methods were conducted on the populations of O. m. irideus in San Simeon and Santa Rosa Creeks during the years of 1993 and 2005. There were very few observations of steelhead moving downstream on both survey creeks in 1993. During the 2005 out-migrant trapping season, the data revealed that non-smolting fish are moving downstream in the watershed in addition to smolting fish. There is evidence that age 1+ and 2+ fish make up the majority of downstream migrants. Older, larger fish tend to migrate downstream earlier in the trapping season. Fork length – weight relationships are not significant between steelhead sampled from out-migrant traps, while those sampled throughout the watersheds by means of electrofishing were different between creeks. Percent frequency distribution of electrofished steelhead reveal that steelhead sampled in 2005 have a similar distribution of total lengths between creeks, where as those sampled in 1993 have a slightly different distribution from each other. Further analysis of steelhead scales sampled from the populations on San Simeon and Santa Rosa Creeks in 2005 gave greater insight into the growth of these fish. In most cases, steelhead from Santa Rosa Creek have greater growth increments and higher circuli counts per annuli than those surveyed from San Simeon Creek. The majority of scale samples analyzed showed growth since the last annuli mark suggesting an increase in growth over the winter months. The average number of circuli to the first annuli is significantly different between watersheds, as is the relationship between fork length and scale radius. Analyzing steelhead demographics is important to understanding the life history pattern of steelhead in the South Central California Coast Distinct Population Segment (DPS). Surveys that monitor environmental conditions and habitat help to identify potential limiting factors and risks to steelhead populations. The results of this thesis present such data in hopes to promote continued research and efficient management practices of steelhead trout populations in San Luis Obispo County.

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Williamson, Benjamin. "Developing a holonomic iROV as a tool for kelp bed mapping." Thesis, University of Bath, 2013. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600219.

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Kelp beds support a vast and diverse ecosystem including marine mammals, fish, invertebrates, other algae and epibiota, yet these kelp beds can be highly ephemeral. Mapping the density and distribution of kelp beds, and assessing change over yearly cycles, are important objectives for coastal oceanography. However, nearshore habitat mapping is challenging, affected by dynamic currents, tides, shallow depths, frequent non-uniform obstacles and often turbid water. Noisy and often incomplete sensor data compound a lack of landmarks available for navigation. The intelligent, position-aware holonomic ROV (iROV) SeaBiscuit was designed specifically for this nearshore habitat mapping application and represents a novel synthesis of techniques and innovative solutions to nearshore habitat mapping. The concept of an iROV combines the benefits of autonomous underwater navigation and mapping while maintaining the flexibility and security of remote high-level control and supervision required for operation in hostile, complex underwater environments. An onboard battery provides an energy buffer for high-powered thrust and security of energy supply. Onboard low-level autonomy provides robust autopilot features, including station-keeping or course-holding in a flow, allowing the operator to direct the survey and supervise mapping data in realtime during acquisition. With the aim of providing high-usability maps on a budget feasible for small-scale field research groups, SeaBiscuit fuses the data from an orthogonal arrangement of a forward-facing multibeam sonar and a complementary 360° scanning sonar with a full navigation suite to explore and map the nearshore environment. Sensor fusion, coupled with the holonomic propulsion system, also allows optimal use of the information available from the limited budget sensor suite. Robust and reliable localisation is achieved even with noisy and incomplete sensor data using a relatively basic Inertial Navigation System and sonar-aided SLAM in the absence of an expensive Doppler velocity log or baseline navigation system. Holonomic motion in the horizontal plane and an axisymmetric hull provide the manoeuvrability required to operate in this complex environment, while allowing 3D maps to be generated in-transit. The navigation algorithms were tested mapping a piling dock and the habitat mapping sensors calibrated using an ‘artificial’ kelp bed of manually dimensioned kelp stipes transplanted to a sheltered but open-water real-world environment. Sea trials demonstrated mapping open ocean kelp beds, identifying clusters of stipes, converting this into a useful measure of biomass and generating a density surface across the kelp bed. This research provides field-proven techniques to improve the nearshore habitat mapping capabilities of underwater vehicles. Future work includes the transition to full-scale kelp bed mapping, and further development of the vehicle and sensor fusion algorithms to improve nearshore navigation.

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Dunn, Shanna K. "Analyzing Spatial Patterns in Reefscape Ecology Via Remote Sensing, Benthic Habitat Mapping, and Morphometrics." NSUWorks, 2009. http://nsuworks.nova.edu/occ_stuetd/234.

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A growing number of scientists are investigating applications of landscape ecology principles to marine studies, yet few coral reef scientists have examined spatial patterns across entire reefscapes with a holistic ecosystem-based view. This study was an effort to better understand reefscape ecology by quantitatively assessing spatial structures and habitat arrangements using remote sensing and geographic information systems (GIS). Quantifying recurring patterns in reef systems has implications for improving the efficiency of mapping efforts and lowering costs associated with collecting field data and acquiring satellite imagery. If a representative example of a reef is mapped with high accuracy, the data derived from habitat configurations could be extrapolated over a larger region to aid management decisions and focus conservation efforts. The aim of this project was to measure repeating spatial patterns at multiple scales (10s m2 to 10s km2) and to explain the environmental mechanisms which have formed the observed patterns. Because power laws have been recognized in size-frequency distributions of reef habitat patches, this study further investigated whether the property exists for expansive reefs with diverse geologic histories. Intra- and inter-reef patch relationships were studied at three sites: Andavadoaka (Madagascar), Vieques (Puerto Rico), and Saipan (Commonwealth of the Northern Mariana Islands). In situ ecological information, including benthic species composition and abundance, as well as substrate type, was collected with georeferenced video transects. LiDAR (Light Detection and Ranging) surveys were assembled into digital elevation models (DEMs), while vessel-based acoustic surveys were utilized to empirically tune bathymetry models where LiDAR data were unavailable. A GIS for each site was compiled by overlying groundtruth data, classifications, DEMs, and satellite images. Benthic cover classes were then digitized and analyzed based on a suite of metrics (e.g. patch complexity, principle axes ratio, and neighborhood transitions). Results from metric analyses were extremely comparable between sites suggesting that spatial prediction of habitat arrangements is very plausible. Further implications discussed include developing an automated habitat mapping technique and improving conservation planning and delimitation of marine protected areas.

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Frantz, Mack Wilson. "Is spot mapping missing important aspects of golden-winged warbler (Vermivora chrysoptera) breeding habitat?" Thesis, Indiana University of Pennsylvania, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1536671.

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The Golden-winged Warbler (Vermivora chrysoptera) is an imperiled migratory songbird that nests in young forest habitats of eastern North America. As such, this species has recently been the focus of an intensive multi-year, range-wide, breeding ecology study. A major focus of this research involved spot-mapping color banded males to examine relationships between nesting success and territory-scale habitat variables. I compared differences in space and habitat use of individual male Golden-winged Warblers that were monitored using both spot mapping and radio telemetry. An individual's telemetry delineated use area was on average 3.6 times larger than its spot-mapped territory. Almost half (46%) of all telemetry locations were located outside their respective male's spot-mapped territory. Number of saplings was higher in telemetry use areas (22.49 ± 2.14) than spot-mapped territories (11.80 ± 1.86). Although the exact motive for extra-territorial movements is unknown, foraging and/or suggestive observations of extra-pair copulation are likely motivating factors. The results of my study suggest Golden-winged Warblers are seeking resources outside their spot-mapped delineated territories. Furthermore, Golden-winged Warblers were found to have more telemetry locations in mature forest than found through spot-mapping. Ultimately, spot mapping alone does not accurately reflect Golden-winged Warbler space use and habitat needs.

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Shanmugam, S. "Airborne remote sensing and digital image analysis for habitat mapping in coastal dune systems." Thesis, Swansea University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638810.

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This thesis examines the application of digital multispectral remote sensing to identify, map and monitor coastal dune habitats that are under threat due to various environmental factors. In addition to multispectral image classification techniques, ground spectro-radiometry, derivative spectra and linear mixture modelling are used. With the availability, in the near future, of high spatial resolution, hyperspectral images acquired by satellite sensors, these techniques may aid in regular monitoring of coastal dunes as well as other habitats, and therefore help environmental managers to conserve biodiversity. The spectral characteristics and separability of various cover types present in the dune and slack habitats of the Kenfig NNR (National Nature Reserve) south Wales are analysed using high spectral and spatial resolution image data acquired by the CASI (Compact Airborne Spectrographic Imager) sensor. It is shown that only broad categories of the habitats can be separated using these data, and that the overall separability between habitats decreases as the number of habitats considered for analysis increases. In a similar fashion, conventional 'hard' classification techniques result in accurate mapping of only the broader categories of these habitats. Sub-community level information cannot be obtained with acceptable accuracy, due to factors such as overlapping spectra, 'fuzzy' boundaries of the habitats and communities on the ground, and the limitations imposed by the spatial and spectral resolution of the image data used. A better understanding of the spectral and habitat variables is achieved by analysing field spectra, derivative spectra, and classified digital, ground-based photography. Empirical models developed from data designed to simulate the bandsets of the Daedalus ATM (Airborne Thematic Mapper) and CASI airborne sensors suggest that the percentage cover of sand, green biomass and the dominant species and communities may be predicted with an average error estimate of 10%.

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Baigas, Phillip E. "Winter habitat selection, winter diet, and seasonal distribution mapping of moose (Alces alces shirasi) in southeastern Wyoming." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1797714121&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Hyde, Peter. "Measuring and mapping forest wildlife habitat characteristics using LiDAR remote sensing and multi-sensor fusion." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3205.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.
Thesis research directed by: Geography. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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McHugh, Nicola. "Incorporating ecological networks and green infrastructure into spatial strategies mapping optimal locations for habitat banks." Thesis, Oxford Brookes University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520926.

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Hogg, Oliver Thomas. "An integrated ecological and geophysical approach to habitat mapping and its application in marine conservation." Thesis, University of Southampton, 2018. https://eprints.soton.ac.uk/424752/.

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Global biodiversity is in decline, with the marine environment experiencing significant and increasing anthropogenic pressures. As a response, very large (105–106 km2) marine protected areas (MPAs) have become the dominant form of environmental protection in the marine environment. At present, however, paucity in scientific sampling makes prioritising which regions of the ocean to protect, especially over such large spatial scales, particularly problematic. One such very large MPA, covering an area of over 1 million Km2, is located at the sub-Antarctic South Georgia and South Sandwich Islands (SGSSI). This study uses the SGSSI MPA as a model system to assess the application of benthic habitat mapping as an evidence-based framework for the spatial prioritisation of marine conservation. This study presents an interdisciplinary methodology to marine landscape mapping, as a top-down, objective statistical approach to hierarchically partition and map the benthic environment into physical habitats types. Ordination analysis demonstrates a statistically significant relationship between environmentally-derived landscape mapping clusters and the composition of benthic species data from the region, thus attributing ecological relevance to the marine landscape map. Furthermore, this study adopts a bottom-up approach to habitat mapping, using an ensemble of habitat suitability models. Potential distributions are modelled for a range of benthic faunal attributes relevant to marine management, based on taxonomic classification, functional traits and vulnerability to disturbance. These modelled distributions are used to describe, for the first time, the bio-physical characteristics of SGSSI’s benthic environment. Synthesising both top-down and bottom-up approaches to habitat mapping, this study assesses the physical landscape clusters and modelled distribution results in relation to the spatial protection currently enforced at SGSSI. This synthesis addresses, (i) whether marine spatial planning in the region is representative in terms of the habitats and fauna it protects; and (ii) whether this interdisciplinary methodology at SGSSI can inform on MPA design and designation more universally, in what is an increasingly exploited, yet still poorly understood marine environment.

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PALIAGA, ENRICO MARIA. "Upper slope geomorphology of Sardinian southern continental margin, applications to habitat mapping supporting marine strategy." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266760.

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This work, framed within the Marine Strategy Framework Directive, is focused on Sardinian southern continental margins marine habitat mapping. Aim of this thesis is to produce predictive marine habitat mapping, starting from a detailed geomorphologic study integrated with biological and oceanographic data coming both from original direct surveys than from bibliographic data. Underwater remotely operated vehicles (ROV), coupled with multibeam echo-sounder (MBES), enabled to perform interpretative hypothesis validation, controlled sampling and detailed observation of specific mesophotic habitats with noninvasive protocols, which are particularly relevant for habitats of conservation interest. Marine habitat mapping represents the best estimation of the distribution of habitats in a place and at a particular time, this goal have been focused on target biocoenosis A4.26 – “Mediterranean coralligenous communities moderately exposed to hydrodynamic action” and A4.713 – “Caves and overhangs with Corallium rubrum”, as defined by EUNIS classification (European Nature Information System), subsequently reunite under the name of Coralligenous Biocoenosis for the mapping of which has been reached a high level of confidence. Principal drivers for seabed habitat distributions include the type of seabed substrate, depth, light availability and the energy of water movements. For the very first time on Sardinian southern margin a multidisciplinary approach has been used to study the relationship between biotic and abiotic components of marine habitats and how seabed morphologic features influences different benthic biocoenosis development styles, geomorphologic characteristics of settlement for substrates could be important factors structuring benthic biodiversity, by affecting sediment accumulation rates, bottom currents and, ultimately, the rates of food supply. These biocoenosis hosts relevant commercially relevant species, as the blue and the giant red shrimp which represent the most important demersal resources for trawling fleet of Sardinia.

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Rice, Patricia. "Landscape ecology of the Souss Massa National Park, southern Morocco and applications for the modelling of bald ibis (Geronticus eremita L.) habitat suitability." Thesis, University of Derby, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248820.

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Stellino, Sabrina. "Mappatura degli habitat e degli oggetti antropici della laguna di Venezia." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9602/.

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L’utilizzo del Multibeam Echo sounder (MBES) in ambienti di transizione poco profondi, con condizioni ambientali complesse come la laguna di Venezia, è ancora in fase di studio e i dati biologici e sedimentologici inerenti ai canali della laguna di Venezia sono attualmente scarsi e datati in letteratura. Questo studio ha lo scopo di mappare gli habitat e gli oggetti antropici di un canale della laguna di Venezia in un intervallo di profondità tra 0.3 e 20 m (Canale San Felice) analizzando i dati batimetrici e di riflettività (backscatter) acquisiti da ISMAR-Venezia nell’ambito del progetto RITMARE. A tale scopo il fondale del canale San Felice (Venezia) è stato caratterizzato dal punto di vista geomorfologico, sedimentologico e biologico; descrivendo anche l’eventuale presenza di oggetti antropici. L’ecoscandaglio utilizzato è il Kongsberg EM2040 Dual-Compact Multibeam in grado di emettere 800 beam (400 per trasduttore) ad una frequenza massima di 400kHZ e ci ha consentito di ricavare ottimi risultati, nonostante le particolari caratteristiche degli ambienti lagunari. I dati acquisiti sono stati processati tramite il software CARIS Hydrographic information processing system (Hips) & Sips, attraverso cui è possibile applicare le correzioni di marea e velocità del suono e migliorare la qualità dei dati grezzi ricavati da MBES. I dati sono stati quindi convertiti in ESRI Grid, formato compatibile con il software ArcGIS 10.2.1 (2013) che abbiamo impiegato per le interpretazioni e per la produzione delle mappe. Tecniche di ground-truthing, basate su riprese video e prelievi di sedimento (benna Van Veen 7l), sono state utilizzate per validare il backscatter, dimostrandosi molto efficaci e soddisfacenti per poter descrivere i fondali dal punto di vista biologico e del substrato e quindi degli habitat del canale lagunare. Tutte le informazioni raccolte durante questo studio sono state organizzate all’interno di un geodatabase, realizzato per i dati relativi alla laguna di Venezia.

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Davies, Jaime Selina. "Mapping deep-sea features in UK waters for use in marine protected area network design." Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/1200.

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With an increase in demand on deep-sea resources comes a need for appropriate and effective management of this ecosystem. The establishment of a representative network of deep-sea Marine Protected Areas offers one tool with which to address the conservation needs of the deep sea. While a number of deep-sea habitats have been identified as vulnerable to anthropogenic activities (e.g. cold-water coral reefs and sponge aggregations), poor knowledge of the distribution of these habitats hinders conservation efforts and network planning, and thus we need habitat maps. With improvements in acoustic data resolution acquired from the deep sea, and the ability to cover large areas rapidly, the use of acoustic techniques in mapping biological habitats is growing. Multibeam bathymetry and its derived terrain variables can potentially provide important information that can aid in the delineation and characterisation of biological communities. A necessary prelude to mapping is therefore the definition of biological assemblages for use as mapping units. Two megahabitat features (seamount and submarine canyons) were sampled using acoustic and ground-truthing to characterise and map the distribution of benthic assemblages. Species were identified as distinct morpho-types and catalogued, and still images quantitatively analysed. Standard multivariate community analysis was undertaken to define distinct faunal assemblage that may act as mapping units. Those clusters identified by the SIMPROF routine were taken against a set of criteria to reject/accept as robust assemblages that may be used as mapping units. Twenty two benthic assemblages or biotopes were defined from multivariate analysis of quantitative species data, 11 from the SW Approaches and 11 from Anton Dohrn Seamount, and a further one from video observations (SW Approaches). Taken against current definitions, 11 of these were considered as Vulnerable Marine Ecosystems (VME). Diversity was measured to compliment the comprehensive description of biotopes. The use of multivariate diversity indices proved better for comparing diversity of biotopes as it captures a more than one aspect of diversity of the community. Two biotopes were common to both megahabitat features, cold-water coral reef habitats, and those from Anton Dohrn Seamount were more diverse than from the SW Approaches. Modelling techniques were employed to test the relationship between biotopes and environmental and geophysical parameters, which may be used as surrogates to map VME. Generalised Additive Models of Vulnerable Marine Ecosystems revealed multibeam bathymetry and its derived parameters to be significant surrogate for mapping the distribution of some assemblages, particularly those that appear to be influenced by current regime; whilst not so well for those whose distribution is not so strongly current driven e.g. soft sediment communities. In terms of deep-sea mapping, the use of multibeam can prove a useful mapping tool if the resolution of the data is at an appropriate scale that will identify meso-scale geomorphological features, such as cliff-top mounds, that may act as proxies for occurrence of biotopes, but this relationship is still unclear. Surrogates were used to map VME across the seamount and submarine canyons, and full coverage maps were produced for all biotopes occurring on these megahabitat features.

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Thapa, Vivek. "Analysis of the One-Horned Rhinoceros (Rhinoceros Unicornis) Habitat in the Royal Chitwan National Park, Nepal." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4926/.

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This study analyzes the remaining suitable habitat of the one-horned rhinoceros, Rhinoceros unicornis, in Royal Chitwan National Park of Nepal. An April 2003 Landsat image was classified into eight land cover types: wetland, sand, water, mixed forest, sal forest, agriculture, settlement, and grassland. This image was converted into habitat suitability maps using cover, food, and water. The rhinoceros prefers grassland habitat with oxbow lakes and closed canopy during the monsoon season. Nominal values of five parameters were used to create a map of habitat suitability index. The map was categorized into four habitat classes: highly unsuitable, unsuitable, moderately suitable habitat, and suitable. Landscape metrics, patch metrics and class metrics associated with habitat were determined through the use of FRAGSTATS.

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Rao, Dushyant. "Multimodal learning from visual and remotely sensed data." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/15535.

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Autonomous vehicles are often deployed to perform exploration and monitoring missions in unseen environments. In such applications, there is often a compromise between the information richness and the acquisition cost of different sensor modalities. Visual data is usually very information-rich, but requires in-situ acquisition with the robot. In contrast, remotely sensed data has a larger range and footprint, and may be available prior to a mission. In order to effectively and efficiently explore and monitor the environment, it is critical to make use of all of the sensory information available to the robot. One important application is the use of an Autonomous Underwater Vehicle (AUV) to survey the ocean floor. AUVs can take high resolution in-situ photographs of the sea floor, which can be used to classify different regions into various habitat classes that summarise the observed physical and biological properties. This is known as benthic habitat mapping. However, since AUVs can only image a tiny fraction of the ocean floor, habitat mapping is usually performed with remotely sensed bathymetry (ocean depth) data, obtained from shipborne multibeam sonar. With the recent surge in unsupervised feature learning and deep learning techniques, a number of previous techniques have investigated the concept of multimodal learning: capturing the relationship between different sensor modalities in order to perform classification and other inference tasks. This thesis proposes related techniques for visual and remotely sensed data, applied to the task of autonomous exploration and monitoring with an AUV. Doing so enables more accurate classification of the benthic environment, and also assists autonomous survey planning. The first contribution of this thesis is to apply unsupervised feature learning techniques to marine data. The proposed techniques are used to extract features from image and bathymetric data separately, and the performance is compared to that with more traditionally used features for each sensor modality. The second contribution is the development of a multimodal learning architecture that captures the relationship between the two modalities. The model is robust to missing modalities, which means it can extract better features for large-scale benthic habitat mapping, where only bathymetry is available. The model is used to perform classification with various combinations of modalities, demonstrating that multimodal learning provides a large performance improvement over the baseline case. The third contribution is an extension of the standard learning architecture using a gated feature learning model, which enables the model to better capture the ‘one-to-many’ relationship between visual and bathymetric data. This opens up further inference capabilities, with the ability to predict visual features from bathymetric data, which allows image-based queries. Such queries are useful for AUV survey planning, especially when supervised labels are unavailable. The final contribution is the novel derivation of a number of information-theoretic measures to aid survey planning. The proposed measures predict the utility of unobserved areas, in terms of the amount of expected additional visual information. As such, they are able to produce utility maps over a large region that can be used by the AUV to determine the most informative locations from a set of candidate missions. The models proposed in this thesis are validated through extensive experiments on real marine data. Furthermore, the introduced techniques have applications in various other areas within robotics. As such, this thesis concludes with a discussion on the broader implications of these contributions, and the future research directions that arise as a result of this work.

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Kimanzi, Johnstone Kithiki. "Mapping and modelling the population and habitat of the roan antelope (Hippotragus equinus langheldi) in Ruma National Park, Kenya." Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1095.

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Wildlife-based tourism, which is Kenya’s second largest economic sector, is threatened by the risk of extinction of many wildlife species in the country. The endemic roan antelope (Hippotragus equinus langheldi) now only survives in Ruma National Park (RNP) where its population has been declining continuously since 1976. This thesis investigates the roan’s habitat use and selection, causes of population decline and population viability in RNP with the aim of recommending scientifically-based management interventions for population recovery and sustainable conservation. Roan movement patterns and habitat use were investigated using 4 home range estimation techniques. Habitat selection was studied at multi-spatial scales using compositional analysis, logistic regression, and information-theoretic (IT) and multi-model inference (MMI) techniques. Data for this study consisted of population estimates for roans and other grazers, Landsat images, soil maps, digital terrain data, rainfall records, snare distribution records, and roan ground tracking data. Identification of causes of population decline was carried out using both multivariate and univariate techniques. A generic population viability analysis (PVA) package was used to (i) estimate the likelihood of roan extinction under various management options; and (2) rank the management alternatives for roan population recovery. All 4 home range estimators are useful in characterizing different aspects of the roan home range, but overall the local convex hull method produced the most realistic home ranges. The three habitat selection methods yielded similar results but the IT techniques demonstrated superior qualities as they identified important habitat variables and produced the most accurate model predictions. MMI averaged models coupled with GIS data developed very informative habitat suitability and poaching risk maps. Analysis of habitat selection indicated different usage in seasons and spatial scales depending on water availability, habitat composition and burned status, and distribution of eco-geographical features. High adult mortality due to poaching with snares was identified as the main cause of roan population decline. Other important factors included habitat change and rainfall variability with its associated droughts and floods. PVA showed that under the current conditions, the roan population cannot persist more than 3 decades. Several anti-poaching and prioritized management interventions to curb poaching and promote population recovery are described.

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Tetley, Michael J. "The distr9bution, ecological niche modelling and habitat suitability mapping of the minke whale (balaenoptera acutorostrata) within the North Atlantic." Thesis, Bangor University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531046.

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Ilich, Alexander Ross. "Integrating Towed Underwater Video with Multibeam Acoustics for Mapping Benthic Habitat and Assessing Reef Fish Communities on the West Florida Shelf." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7525.

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Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the supervised classification demonstrated “substantial agreement” (κ>0.6) between observations and predictions for both geologic and biotic habitat, while the results of the unsupervised classification demonstrated “moderate agreement” (κ>0.4) between observations and predictions for both geologic and biotic habitat. Comparisons were made with the previously existing map for this area created by Florida Fish and Wildlife Conservation Commission’s Fish and Wildlife Research Institute (FWC-FWRI). Some features are distinguishable in both maps, but the FWC-FWRI map shows a greater extent of low relief hard bottom features than was predicted in our habitat maps. The areas predicted as low relief hard-bottom by FWC-FWRI often coincide with areas of higher uncertainty in the supervised map of geologic habitat from this study, but even when compared with ground-truth points from the towed video rather than predictions, the low relief hard bottom in FWC-FWRI’s map still corresponds to what was identified as sand in the video 73% of the time. The higher uncertainty might be a result of the presence of mixed habitats, differing morphology of hard-bottom, or the presence of sand intermixed with gravel or debris. More ground-truth samples should be taken in these areas to increase the confidence of these classifications and resolve discrepancies between the two maps. Data from the towed video system were also used to assess differences in fish communities among habitat types and to calculate habitat-specific densities for each taxa. Fish communities were found to significantly differ between soft and hard bottom habitats as well as among the hard-bottom habitats with different vertical relief (flat hard-bottom vs more steeply sloping areas). Additionally, significant differences were found between the fish communities in habitats with attached fauna such as sponges and gorgonians, and areas without attached fauna; however, attached fauna require rock to attach to and the rock habitats rarely lacked attached fauna, so this difference may just reflect the difference between fish communities in sand and rock habitats without the consideration of vertical relief. Moreover, the species driving the differences in the fish communities were identified. Fish were more likely to be present and assemblages were more species rich in more complex habitats (rockier, higher relief, presence of attached fauna). Habitat specific densities were calculated for each species, and general trends are discussed. Lastly the habitat-specific densities were extrapolated to the total area of habitat type (sand vs rock) as predicted by the supervised geologic habitat map. There is predicted to be approximately 111,000 fish (95% CI [67015, 169405]) within the study area based on this method, with ~47,000 (~43%) predicted to be within the sand habitat and ~64,000 (~57%) in the rock habitat. This demonstrates the potential of offshore rocky reefs as “critical habitats” for demersal fish in the offshore environment as rock accounts for just 4% of the study area but is expected to contain over half of the total abundance. The value of sand habitats is also shown, as due to their large area they are able to contribute substantially to the total number of fish despite sustaining comparatively low densities.

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net, matt@harves, and Matthew Harvey. "Development of techniques to classify marine benthic habitats using hyperspectral imagery in oligotrophic, temperate waters." Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20091118.110704.

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There is an increasing need for more detailed knowledge about the spatial distribution and structure of shallow water benthic habitats for marine conservation and planning. This, linked with improvements in hyperspectral image sensors provides an increased opportunity to develop new techniques to better utilise these data in marine mapping projects. The oligotrophic, optically-shallow waters surrounding Rottnest Island, Western Australia, provide a unique opportunity to develop and apply these new mapping techniques. The three flight lines of HyMap hyperspectral data flown for the Rottnest Island Reserve (RIR) in April 2004 were corrected for atmospheric effects, sunglint and the influence of the water column using the Modular Inversion and Processing System. A digital bathymetry model was created for the RIR using existing soundings data and used to create a range of topographic variables (e.g. slope) and other spatially relevant environmental variables (e.g. exposure to waves) that could be used to improve the ecological description of the benthic habitats identified in the hyperspectral imagery. A hierarchical habitat classification scheme was developed for Rottnest Island based on the dominant habitat components, such as Ecklonia radiata or Posidonia sinuosa. A library of 296 spectral signatures at HyMap spectral resolution (~15 nm) was created from >6000 in situ measurements of the dominant habitat components and subjected to spectral separation analysis at all levels of the habitat classification scheme. A separation analysis technique was developed using a multivariate statistical optimisation approach that utilised a genetic algorithm in concert with a range of spectral metrics to determine the optimum set of image bands to achieve maximum separation at each classification level using the entire spectral library. These results determined that many of the dominant habitat components could be separated spectrally as pure spectra, although there were almost always some overlapping samples from most classes at each split in the scheme. This led to the development of a classification algorithm that accounted for these overlaps. This algorithm was tested using mixture analysis, which attempted to identify 10 000 synthetically mixed signatures, with a known dominant component, on each run. The algorithm was applied directly to the water-corrected bottom reflectance data to classify the benthic habitats. At the broadest scale, bio-substrate regions were separated from bare substrates in the image with an overall accuracy of 95% and, at the finest scale, bare substrates, Posidonia, Amphibolis, Ecklonia radiata, Sargassum species, algal turf and coral were separated with an accuracy of 70%. The application of these habitat maps to a number of marine planning and management scenarios, such as marine conservation and the placement of boat moorings at dive sites was demonstrated.

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Rossi, Alessandra. "Mappatura degli habitat bentonici delle aree di Burano e Torcello, con particolare attenzione alla componente macroalgale." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13385/.

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Il benthic habitat mapping è un processo che integra diverse discipline e dataset. Le mappe sono utili per la gestione e la tutela degli ecosistemi; tra questi, le lagune costiere sono obiettivo di protezione da parte di numerose direttive europee, come la Dir. Habitat e la Water Framework Directive. Le lagune sono sistemi altamente produttivi e forniscono habitat unici ed indispensabili per alcune specie animali e vegetali; inoltre, forniscono numerosi servizi ecosistemici. Nel Mediterraneo la più importante ed estesa è la Laguna di Venezia. Gli obiettivi di questa tesi sono mappare e classificare le forme fisiografiche e morfologiche, i tipi di substrato, la componente biologica e gli oggetti antropici dei canali circondanti le isole di Burano e Torcello, con particolare attenzione alla componente macroalgale, ottenendo alla fine una mappa degli habitat bentonici. Tramite MultiBeam EchoSounder ad alta risoluzione sono stati acquisiti dati batimetrici e di backscatter, analizzati con ArcGIS ed integrati con campionamenti mediante dropframe. Dall’analisi dei dati è risultato che nell’area sono presenti, in ordine decrescente di estensione, le forme fisiografiche pool, bar e point bar e le forme morfologiche 3d-dunes, 2d-dunes, furrow, scour hole, obstacle mark e scour. Le forme elencate sono coerenti con il tipo di substrato, che è risultato prevalentemente sabbioso-fangoso, con presenza di patches di tipo hard. Il substrato risulta spesso bioturbato da molluschi, crostacei e, soprattutto, policheti. Sono anche presenti associazioni di spugne e macroalghe, le quali sono state classificate secondo il gruppo morfo-funzionale, che tiene conto della struttura e non della specie. Questo studio ha dimostrato che i MBES ad alta risoluzione possono essere utilizzati in ambienti poco profondi per ottenere una mappa continua degli habitat bentonici, in tempi relativamente brevi e con grande dettaglio. Inoltre, ha fornito una base per un futuro studio comparativo.

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Korswagen, Eguren Stefanie. "Spatial analysis of vicugna’s habitat in a Peasant Community in Nor Yauyos Cochas Landscape Reserve." Pontificia Universidad Católica del Perú. Centro de Investigación en Geografía Aplicada, 2016. http://repositorio.pucp.edu.pe/index/handle/123456789/119903.

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In Peru, research and practices that contribute to Andean natural resources’ sustainable management are needed. The Nor Yauyos Cochas Landscape Reserve is home to a wild vicugna population, which can be viewed as a key resource for conservation and sustainable development. However, some activities of Tanta Peasant Community impact negatively on vicugna’s habitat. The research aimed to determine spatial relations and impacts of Tanta’s activities on vicugna’s habitat and distribution over communal territory.A participatory mapping workshop was applied to determine vicugna’s actual distribution and local activities that could influence vicugna’s habitat. The species’ potential habitat was estimated with a species distribution model named Maxent. Spatial relations between vicugna’s actual distribution, its potential habitat and communal activities were analysed. Results indicate that potential habitat is determined by environmental conditions, while human presence and domestic livestock determine vicugna’s actual distribution. Based on the research process, recommendations relating vicugna’s sustainable management in the study area are given.The results are valuable to local community and conservation agents. Main contributions consist in generating a space for exchanging knowledge during the workshop, as well as the integration of analysis methods in physical and human geography.
En el Perú son necesarias investigación y prácticas que contribuyan al manejo sostenible de los recursos alto-andinos. La Reserva Paisajística Nor Yauyos Cochas alberga una población silvestre de vicuñas, que pueden ser clave para la conservación y desarrollo sostenible. Sin embargo, en la Comunidad Campesina de Tanta algunas actividades impactan negativamente en el hábitat de la vicuña. La investigación buscó determinar las relaciones espaciales e impactos de las actividades de la Comunidad Campesina de Tanta sobre el hábitat y la distribución de la vicuña en el territorio comunal. Mediante un taller de mapeo participativo se determinaron la distribución actual de las vicuñas y las actividades comunales que pueden influir sobre su hábitat. El hábitat potencial de la especie se estimó con el modelo de distribución de especies Maxent. Se analizaron las relaciones espaciales entre la distribución actual de la vicuña, su hábitat potencial y las actividades comunales. Los resultados indican que el hábitat potencial está determinado por condiciones ambientales, mientras que la distribución actual está determinada por la presencia humana y del ganado doméstico. En base al proceso de investigación se incluyen recomendaciones en relación al manejo sostenible de la vicuña en el área de estudio. Los resultados son de interés para la comunidad local y agentes de conservación. Aportes principales consisten en la generación de un espacio de intercambio de conocimientos en el taller, así como la integración de métodos de análisis en geografía física y humana.

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Secchin, Nelio Augusto. "Mapeamento de habitats marinhos no banco dos Abrolhos." reponame:Repositório Institucional da UFES, 2011. http://repositorio.ufes.br/handle/10/2008.

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A plataforma continental tropical é composta por um mosaico de megahabitats que suportam uma alta diversidade de habitats, e atualmente vêm sofrendo com as pressões antrópicas. O desenvolvimento e a aplicação de geotecnologias em estudos de mapeamento do substrato marinho vêm proporcionando um aumento no conhecimento dos habitats bentônicos. Importante formação coralínea do Atlântico Sul, a Plataforma dos Abrolhos, não possui informações suficientes que possibilitem uma gestão efetiva. O presente estudo tem com objetivo apresentar uma distribuição espacial e caracterização dos domínios dos principais megahabitats da Plataforma dos Abrolhos. Para tal, foram utilizados dados diretos e indiretos de investigação geológica, com uma combinação metodológica englobando levantamentos de SVL, ecobatímetro monofeixe e ROV, sendo base para uma classificação hierárquica dos megahabitats e integração com dados pretéritos levantados. Alcançando uma representação interpretativa dos tipos de fundo da região estudada (50.500km²), a aplicação metodológica possibilitou gerar uma nova visão para a Plataforma dos Abrolhos. Foram identificados os domínios de megahabitat Recifal (17%), Rodolito (51%), bem como as principais feições de cada um, ocorrendo com variações na distribuição e ocorrência em relação à disposição ao perfil batimétrico. Uma estrutura recifal que ocorre juntamente com o domínio de rodolitos, as Buracas, é um habitat particular que pode ter uma importância significativa para o ecossistema de Abrolhos. A metodologia aplicada foi satisfatória na geração de uma representação da distribuição e descrição de megahabitats marinhos para toda a Plataforma dos Abrolhos. Oferecendo, assim, uma nova abordagem em estudos de delineamento de habitats marinhos aplicados na costa brasileira, sendo importante pela área espacial representada, contida em uma região singular onde havia uma lacuna no conhecimento sobre a distribuição e caracterização deste habitat em toda a sua extensão.
The continental shelf is composed of a tropical mosaic megahabitats that support a high diversity of habitats, and now have suffered from anthropogenic pressures. The development and application of geo-mapping studies of the marine substrate has provided increased knowledge of benthic habitats. The most important coral reef formation of the South Atlantic, Abrolhos Platform, does not have sufficient information to enable effective management. The present study aims at presenting a spatial distribution and characterization of the major fields of the Platform of the Abrolhos' megahabitats. To this end, we used data from direct and indirect geological research, with a combination of surveys covering methodological SSS, and echo sounder, ROV, and the basis for a hierarchical classification of megahabitats and integration with past data collected. Reaching an interpretative representation of the types of background of the region studied (50.500km²), the methodological application was able to generate a new vision for the Platform of the Abrolhos. We identified areas of reef megahabitat (17%), Rhodolite (51%) as well as the main features of each, with variations occurring in the distribution and occurrence in relation to the available bathymetric profile. A reef structures that occurs with the domain Rhodolite, the Buracas, is a particular habitat that may have a significant importance for the ecosystem of Abrolhos. The methodology was applied to generate a satisfactory representation of the distribution and description of marine megahabitats for the entire Abrolhos Platform. Thus offering a new approach to design studies of applied marine habitats along the Brazilian coast, is important for the space represented, contained in a unique region where there was a gap in knowledge about the distribution and characterization of this habitat throughout its length.

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Ferguson, Sean. "Hydraulic Geometry and Fish Habitat in Semi-Alluvial Bedrock Controlled Rivers." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35313.

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The cross-sectional form of semi-alluvial bedrock channels was investigated. Channel geometry data were collected from a variety of streams in Ontario and Québec, Canada to develop empirical downstream scaling relationships. The relationships revealed that bedrock, mixed, and alluvial channels scale at similar rates with respect to discharge. The widest channels were formed in low-relief sedimentary bedrock with minimal alluvial cover. Channels influenced by resistant igneous/metamorphic bedrock produced a strong scaling relationship, whereas channels influenced by weak sedimentary bedrock produced a weak scaling relationship. Alluvial cover appeared to exhibit more control on channel width in low-relief settings in comparison to high-relief settings, with increased alluvial cover promoting channel narrowing. Channels influenced by igneous/metamorphic bedrock produced identifiable thalwegs, presumably due to well-defined bedload transport pathways. Channels influenced by sedimentary bedrock tended to have planar beds. Additionally, fish habitat was investigated at one semi-alluvial bedrock stream in Ontario, Canada. Fish sampling was conducted at proximate bedrock and alluvial sections followed by a survey of physical habitat parameters to evaluate habitat preferences. Adult logperch (Percina caprodes), juvenile white sucker (Catostomus commersonii), adult round goby (Neogobius melanostomus), and adult longnose dace (Rhinichthys cataractae) demonstrated preference toward alluvial substrate, whereas juvenile logperch and adult banded killifish (Fundulus diaphanus) demonstrated preference toward bedrock. Juvenile silver shiner (Notropis photogenis) and juvenile yellow perch (Perca flavescens) were indifferent to substrate type. Empirical depth and flow velocity habitat suitability indices (HSIs) were developed for each fish species. This study presents the first fish habitat suitability criteria developed from a small semi-alluvial bedrock stream and may provide valuable information for fisheries management endeavours in such environments.

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MARCHESE, FABIO. "A geomorphometric approach to assess multi-scale spatial distribution and geomorphological characterization of benthic habitats." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2016. http://hdl.handle.net/10281/103697.

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Quantitative analysis on Digital Elevation Models (DEMs) are rarely conducted on submarine landscapes. Only recently the application of quantitative geomorphometric techniques to the bathymetry data set has been effectively tested and the authors demonstrated their utility in improving the geological interpretation of submarine environments. In this thesis geomorphometric analytical techniques were applied to a high-resolution bathymetry data set acquired along three different survey areas located on the Apulian continental margin, between 5 and 1400m of water depth. We focused our analysis on a supervised computation of the most significant morphometric parameters that typify the surveyed areas to automatically select those seafloor geomorphologies that appear to be linked with occurrences of specific benthic habitats. The work has been done in order to figure out relationships between the observed morphologies and the associated habitat distribution. The objective identification of morphologic features represents indeed a significant step in defining spatial units that are related to geomorphological processes. Our study aims at highlighting the importance of combining acoustic survey techniques and geomorphometric analysis to successfully support a preliminary quantitative assessment of habitats distribution and extent. Our method was specifically designed for the study areas and allowed the identification of a geomorphological proxy (based on geomorphometric parameters) associated with the benthic habitats distribution. The approach should offer an efficient and cost-effective technique for supporting the growing global need for better spatial management within the Mediterranean marine environment.

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Catenacci, Elena. "Mappatura degli habitat bentonici dell'area nord-est di Venezia, con particolare attenzione alla componente macroalgale." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Le lagune costiere sono considerate tra i più produttivi ecosistemi al mondo, un nodo per lo scambio di merci e lo sviluppo industriale e sono zone rilevanti a livello turistico. Costituiscono inoltre un importante sito di elevata biodiversità. A causa dell'influenza dell'uomo sono andate incontro a un declino in tutto il mondo ed essendo ambienti delicati e in continuo cambiamento necessitano di un costante monitoraggio. A riguardo è fondamentale la mappatura degli habitat bentonici (Benthic Habitat Mapping) che permette una descrizione qualitativa e quantitativa degli habitat sommersi, sia sotto un profilo biotico che abiotico, considerando diverse scale spaziali e differenti intervalli temporali. Le innovative tecniche di remote sensing, come il multi-beam ecosounder (MBES), hanno aperto nuove frontiere nel campo dell'habitat mapping e solo di recente sono state applicate ad ambienti poco profondi come i canali della laguna di Venezia fino ad oggi poco esplorati. In questa tesi l'analisi, l'interpretazione e l'elaborazione dei dati di batimetria e backscatter acustico, congiuntamente alla realizzazione di video del fondali e all'analisi dei campioni fotografici estratti da essi, hanno permesso di mappare i canali che si estendono dalla bocca di porto di Lido fino all’isola di Murano (area a nord-est di Venezia), ponendo attenzione alla componente macroalgale. I risultati ottenuti confermano la natura prevalentemente sabbiosa-fangosa del substrato, in cui sono più o meno visibili tracce superficiali di infauna, in relazione alla quantità di detrito conchigliare presente, ed organismi bentonici animali e/o vegetali. Sono stati rinvenuti infatti organismi quali spugne, anemoni e ofiure e raggruppamenti più o meno isolati di macroalghe corticate o filamentose. Tra gli oggetti antropici mappati i più abbondanti sono le bricole, che delimitano i canali navigabili dell'area.

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Bender, Asher. "Autonomous Exploration of Large-Scale Natural Environments." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/9450.

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This thesis addresses issues which arise when using robotic platforms to explore large-scale, natural environments. Two main problems are identified: the volume of data collected by autonomous platforms and the complexity of planning surveys in large environments. Autonomous platforms are able to rapidly accumulate large data sets. The volume of data that must be processed is often too large for human experts to analyse exhaustively in a practical amount of time or in a cost-effective manner. This burden can create a bottleneck in the process of converting observations into scientifically relevant data. Although autonomous platforms can collect precisely navigated, high-resolution data, they are typically limited by finite battery capacities, data storage and computational resources. Deployments are also limited by project budgets and time frames. These constraints make it impractical to sample large environments exhaustively. To use the limited resources effectively, trajectories which maximise the amount of information gathered from the environment must be designed. This thesis addresses these problems. Three primary contributions are presented: a new classifier designed to accept probabilistic training targets rather than discrete training targets; a semi-autonomous pipeline for creating models of the environment; and an offline method for autonomously planning surveys. These contributions allow large data sets to be processed with minimal human intervention and promote efficient allocation of resources. In this thesis environmental models are established by learning the correlation between data extracted from a digital elevation model (DEM) of the seafloor and habitat categories derived from in-situ images. The DEM of the seafloor is collected using ship-borne multibeam sonar and the in-situ images are collected using an autonomous underwater vehicle (AUV). While the thesis specifically focuses on mapping and exploring marine habitats with an AUV, the research applies equally to other applications such as aerial and terrestrial environmental monitoring and planetary exploration.

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Khoudeir, Riad. "L'amélioration de l'habitabilité automobile de demain : l'application des principes de la construction architecturale de la maison dans la conception de l'habitacle des concepts-cars." Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL004N/document.

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Notre recherche s’inscrit dans le domaine du génie industriel. Elle porte sur l’amélioration de l’habitabilité de l’habitacle de l’automobile de demain. Cette étude met en évidence l’influence de la conception de l’habitat sur la conception de l’habitacle de l’automobile. L’objectif de ce travail est de proposer un outil destiné à aider le concepteur de l’automobile à introduire les principes de la construction architecturale de l’habitat dans la conception de l’habitacle de l’automobile pour améliorer son habitabilité. Dans notre démarche expérimentale nous avons adopté des principes de la méthode d’analyse des tendances conjointe comme les mappings et les planches de catégorisation. Cette démarche montre que les concepteurs de l’automobile ont orienté leur démarche vers l’intégration de plus en plus de principes de la construction architecturale de l’habitat dans la conception de l’habitacle des concept-cars. L’enquête que nous avons effectuée auprès des architectes et des designers nous a confirmé que l’habitat et l’automobile partagent les mêmes critères de l’habitabilité. Aussi, elle nous a affirmé l’impact positif des principes de la construction architecturale de l’habitat sur l’amélioration des critères de l’habitabilité dans l’espace de l’habitacle automobile. Notre recherche ouvre des perspectives pour analyser l’impact des autres secteurs d’influence comme l’aéronautique et l’électronique sur la conception de l’automobile. Aussi, elle montre l’importance de l’analyse de l’impact de la conception de l’automobile sur la conception de l’habitat du futur
The research field of this work is Industrial Engineering. This paper presents a study made to improve tomorrow’s automobile cabin habitability. It is focused on showing the influence on car-interior design by today’s home-interior design. The objective of this work is to propose a tool intended to help automobile designers to introduce home architectural construction principles into the car’s cabin design to improve its habitability. In our experimental phase we adopted principles of the method of analysis of the joint tendencies such as mappings and boards of categorization. This step showed that car designers have been increasingly using the home architectural construction principles on the car’s cabin conception design. Our research took into account the opinion of experts in both areas: architecture and design. In this way, we can be certain that the home and the automobile share the same criteria of habitability. We could also confirm that home architectural principles have a positive impact on the improvement of the habitability criteria in space design of the automobile’s cabin. This work opens a research line to analyze the influence of different areas in automobile design, such as aeronautics and electronics. This study can also show the inverse perspective of how car design can eventually have an impact on the future home design

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Eddings, James B. "The Utility of Environmental DNA and Species Distribution Models in Assessing the Habitat Requirements of Twelve Fish Species in Alaskan North Slope Rivers." DigitalCommons@USU, 2020. https://digitalcommons.usu.edu/etd/7708.

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Subsistence fishing is a vital component of Alaska’s North Slope borough economy and culture that is being threatened by human disturbance. These threats mean the fish must be protected, but the size of the region makes conservation planning difficult. Fortunately, advances in species distribution models (SDMs), environmental DNA (eDNA), and remote sensing technologies provide potential to better understand species’ needs and guide management. The objectives of my study were to: (1) map the current habitat suitability for twelve fish species, occurring in Alaska’s North Slope,(2) determine if SDMs based on eDNA data performed similarly to, or improved, models based on traditional sampling data, and (3) predict how species distributions will shift in the future in response to climate change. I was able to produce robust models for 8 of 12 species that relate environmental characteristics to a species’ presence or absence and identify stream reaches where species are likely to occur. Unfortunately, the use of eDNA data did not produce useful models in Northern Alaskan rivers. However, I was able to generate predictions of species distributions into the future that should help inform management for years to come.

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Burck, Michael Theodore. "MAPPING RIPARIAN BUFFER ZONES IN CYPRESS CREEK REFUGE, ILLINOIS: LAND USE CHANGE IMPACT ON HABITAT USAGE FROM 1984-2014: PASSERINE PRESENCE AND CLASSIFICATION COMPARISONS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2229.

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In response to recent declines, forested riparian wetland areas have become an increased conservation and management area of concern focusing on increasing biodiversity and promoting healthy ecosystem services. Additionally, passerine birds have also experienced a sharp global decline in that associated habitat. To mitigate further declines of both habitat and species numbers government programs and agencies have intensified conservation efforts. However, the practices employed are often assumed to be beneficial without conducting dedicated surveys to measure efficacy and practicality of current approaches. As such, visual evidence and statistics are often needed to promote or validate further support and funding for continuing with current polices or creating new focal areas and practices. This study strives to provide an inexpensive, efficient way to assess conservation areas based on a target species through a generalized and adaptive methodology. The Cypress Creek National Wildlife Refuge in southern Illinois provides an opportunity to do just that with a focus on songbirds. The methodology outlined in this study implements multiple remote sensing land use and land cover classification techniques utilizing Landsat imagery from 1984 to 2014 to create a temporal analysis of the region from pre-refuge era to current refuge designated era. Field surveys from the 2015 songbird summer breeding and fall migration seasons as well as vegetation surveys for field-truthing supplement the remote sensing results. The classification methodology incudes a combination of pan-sharpening Landsat images to a 15 m x 15 m spatial resolution, texture analysis, object based image analysis, and Random Forests to produce land use and land cover maps. For the sake of comparison the same classification process is performed with the untransformed, source images at 30 m x 30 m spatial resolution. Landscape metrics such as the interspersion and juxtaposition index and the contiguity index also provide further insight to temporal landscape patterns. At the completion of the study it was found that there was a minimal difference between the overall classification accuracy of transformed and untransformed images and that lowest overall accuracy in the study was 91% while the highest was 98%. The key survey statistics concluded that during the summer and fall observation periods songbirds in forested wetland areas had a propensity to utilize areas closest to the wetland edge as opposed to inland areas. Furthermore, during fall migration it was concluded that the mixed forest habitat type had a direct effect on observation numbers. Overall, with the aid of multiple landscape metrics, it was shown that the region was increasing in forested area, patch density, and contiguity; in response the passerines were using the area at a high rate, especially near wetland edges creating a sustainable focal area for conservation and management. The methodology and results in this study contribute to an ongoing effort to provide visual and statistical evidence that is reliable and accessible for policy making. The potential to manipulate the generalized methods used in this study to enhance any land use and land class classifications and apply to any targeted species certainly exists. Future studies will want to investigate the use of higher spatial resolution images or actively take reflectance recordings in the field and supplement the temporal maps with a multi-year dedicated species dataset for maximum benefit.

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47

Bastari, Azzurra. "Analysis of the Adriatic macrobenthic assemblages along a spatio-temporal gradient. Habitat mapping as a tool to address restoration and recovery of marine resources." Doctoral thesis, Università Politecnica delle Marche, 2016. http://hdl.handle.net/11566/243051.

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Il mare Adriatico è una delle regioni del bacino Mediterraneo più impattate poiché soggetto a multipli fattori di stress, come cambiamenti climatici e una lunga storia di intenso sfruttamento delle risorse. Allo stesso tempo ospita una grande varietà di endemismi, aree di riproduzione, nursery e foraggiamento. Il drammatico declino delle risorse target e non del mare Adriatico richiede un urgente sviluppo di nuove ed idonee misure di gestione e conservazione degli ecosistemi marini. Il cambiamento delle comunità macrobentoniche di fondo mobile può innescare un’alterazione delle reti trofiche, della qualità delle acque, del riciclo dei nutrienti. Pertanto, un’efficiente gestione degli ecosistemi marini non può prescindere dal recupero degli habitat bentonici. I risultati di questo lavoro di dottorato hanno permesso di evidenziare i principali cambiamenti avvenuti sulle comunità bentoniche dei fondali del largo del mare Adriatico (centro e nord) nel corso di circa 60 anni (1934 – 1998). Si è osservato un declino degli organismi dell’epifauna e delle specie macrobentoniche più fragili con Spugne ed Echinodermi che si sono ridotti fino ad un 90-70%. Tuttavia, lo sviluppo di modelli di preferenza degli habitat dei pennatulacei ha confermato che i fondi mobili del largo Adriatico sono habitat ideali per le specie Funiculina quadrangularis e Pennatula phosphorea. Virgularia mirabilis, invece, predilige le zone sabbiose-fangose del nord e della costa occidentale. Una dettagliata descrizione morfologica di P. phosphorea e Pteroeides spinosum è stata condotta per cercare di fornire uno strumento che possa agevolare il riconoscimento di specie ancora oggi spesso confuse a causa di descrizioni finora poco dettagliate. La tesi è stata disegnata al fine di fornire utili elementi scientifici a supporto del progetto “Adriatic Marine Ecosystem Recovery” (AMER), avente lo scopo di avviare processi utili al recupero degli ormai sovrasfruttati e degradati habitat marini del mare Adriatico.
The Adriatic Sea is one of the most depleted regions of the Mediterranean Sea due to a cumulative impact of multiple stressors, such as climate change and a long history of intense exploitation. At the same time it hosts a variety of endemism, of vulnerable marine ecosystems and essential fish habitats. Severe decline of target and by-catch species call for urgent conservation measures. The ecological importance of soft bottoms macrobenthic community have been increase and their changes can lead to an alteration of food-webs, reduction of water quality, or nutrient cycling. An efficient ecosystem-based management focusing on the recovery of key benthic habitats is needed to promote recovery of stocks and to develop a sustainable exploitation of marine resources. The results of this PhD work gives a picture of the main changes occurred on macrobenthic soft bottoms communities of the north and central Adriatic Sea during 60 years (1934 – 1998). Overall change are the decline of epifauna organisms and of the most fragile macrobenthos species with sponges and echinoderms declined by 90-70% since the 1900s. However, the study of the spatial and bathymetric distribution of Adriatic sea-pens and the development of suitability habitats models have confirmed that the soft bottoms of the central offshore Adriatic Sea are favourable bottoms for Funiculina quadrangularis and Pennatula phosphorea. Virgularia mirabilis prefers the northern basin and the sandy-muddy occidental coastlines. A detailed morphological description of P. phosphorea and Pteroeides spinosum was also provided as a useful tool to sea-pens classification, usually misidentify because a lack of clear available taxonomical descriptions. The thesis has been designed in order to provide useful scientific elements to support the ‘Adriatic Marine Ecosystem Recover’ (AMER) project, which main aim is provide processes to promote recovery of depleted and overexploited fish stocks and habitats of the Adriatic Sea.

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48

Fantoni, Giulia. "L'analisi dei popolamenti bentonici nel monitoraggio della fascia costiera nella zona della spiaggia "attiva"." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Sandy marine coastal habitats provide ecosystem services such as food supply, food web structure, and habitat provision. However, these habitats are subject to various anthropogenic disturbances, including coastal urban development and the construction of coastal defence structures. These habitats are very dynamic and difficult to investigate and monitor with conventional techniques. In this context, the TAO project, Technologies for Coastal Monitoring (Formally: Tecnologie per il monitorAggio cOstiero), focus on the implementation of a technological platform, helpful in developing monitoring plans with low environmental impact and low cost, for the investigation of littoral and supra / sub-littoral areas. This thesis, which is part of the TAO project, aims to provide useful data for evaluating the validity of these new monitoring technologies by mapping both the data obtained from the surveys carried out using acoustic instruments (Single-Beam Echosounder and Side-Scan Sonar installed aboard the autonomous OpenSWAP vehicle), and the data on the characteristics of sediments and benthic assemblages collected through direct sampling in scuba diving at Lido di Dante (northern Adriatic Sea) study site. A comparative integration of the physical-biological data and the geophysical data, recorded continuously by the acoustic instruments, was carried out. The data collected were interpolated to the entire study area and represented through cartographic software. The different variables were analyzed and correlated with each other with innovative spatial correlation techniques through linear models. This allowed highlighting possible anomalies in the characteristics of the sediments and in the distribution of the benthic assemblages that can be related both to natural sedimentological and ecological processes and to alterations induced by the presence of coastal defence structures. These integrated approaches provide innovative tools for integrated coastal zone management.

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49

Cumming, Kristen A. "The Relationship between Near Shore Hardbottom Exposure and Benthic Community Composition and Distribution in Palm Beach County, FL." NSUWorks, 2017. http://nsuworks.nova.edu/occ_stuetd/439.

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Anthropogenic changes to the landscape, storm events and sea level rise are contributing to the erosion of beaches leading to an increase of the sediment load in near shore marine environments. Palm Beach, Florida is host to unique near shore hardbottom habitats. These areas are distinct from the vast expanses of surrounding sediments and play and important role of habitat and shelter for many different species. In this study, remotely sensed images from 2000-2015 were used to look at the movement of sediment and how it contributes to exposure rates of near shore hardbottom habitats in Palm Beach, Florida and how these factors affect the benthic community. GIS was used to determine areas of hardbottom with high exposure (exposed in >60% of aerial images), medium exposure (40-60%), and low exposure ( I strived to determine if one can detect a successional relationship of benthic communities in a dynamic environment with annual mapping. I also examined if areas with higher exposure rates have more complex successive communities than those with lower exposure rates, and what implications this has on near shore benthic communities. In situ surveys conducted at 117 sites determined the community structure (corals, octocorals, macroalgae, and hydroids). This study confirmed that periodic mapping was successful in identifying hardbottom burial and exposure, which fluctuate both spatially and temporally. This periodic mapping along with manual delineation did identify hardbottom burials and exposures that fluctuate between years and relate to benthic community differences. The near shore hardbottom coral reef communities aligned with the observed exposure categories with the greater coral species richness and octocoral morphologies found at sites classified as highly exposed. Statistical analyses showed differences in communities shallower and deeper than three meters’ depth. Increasing the frequency of imagery captures and in situ observation would further increase our comprehension of the metrics of hardbottom exposures in reference to community structure.

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50

Newton, Ian Paul. "Recent transformations in West-Coast Renosterveld: patterns, processes and ecological significance." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8396_1263521893.

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This
thesis
examines
the
changes
that
have
occurred
within
West-Coast Renosterveld within
the
last 350 years, and assesses
the viability of
the
remaining fragments.

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