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Survey Techniques (survey + techniques)
Selected AbstractsSURVEY TECHNIQUES AND FIELD-WORKACTA ARCHAEOLOGICA, Issue 1 2009Article first published online: 5 JUL 2010 No abstract is available for this article. [source] A comparison of catchment based salmonid habitat survey techniques in three river systems in Northern IrelandFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2002W. C. K. O'CONNOR Three survey techniques, a fully quantitative, multivariate study; a shorter or truncated fully quantitative method and a Geographical Information System (GIS) based, semi-quantitative, survey technique, were developed to assess in-river salmonid habitats on a catchment wide basis. These methods were tested and compared on three river systems in Northern Ireland: the Blackwater, the Bush and the Main. The research indicated that the fully quantitative method generated an accurate habitat database but required a high investment in time and resources to complete. The truncated survey approach often produced an inaccurate habitat database. The semi-quantitative technique generated a more accurate habitat dataset with greater productivity and efficiency for the resources invested in the survey. [source] Underwater archaeological surveying using PhotoModeler, VirtualMapper: different applications for different problemsINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2002Jeremy Green Techniques of underwater photogrammetry discussed include accuracy measurements and survey techniques. [source] Large-scale processes in ecology and hydrologyJOURNAL OF APPLIED ECOLOGY, Issue 2000R.W.G. Caldow 1. Several papers published in the 1980s stressed the importance of scaling issues, the inter-relatedness of patterns and processes at different scales of time and space, to our understanding of ecological systems. Scaling issues are of major theoretical interest and increasingly are of considerable applied importance. 2. In recognition of this, the Natural Environment Research Council, in partnership with the Scottish Executive Rural Affairs Department, funded a Thematic Programme entitled ,Large-scale Processes in Ecology and Hydrology'. The principal aim of this Programme was to integrate recent major developments in information resources and technologies with current theory in order to improve understanding of large-scale patterns and processes and their relationship to patterns and processes at smaller scales. 3. The Thematic Programme, which ran from 1995 until 1999, funded six research projects that have generated a large body of published papers. This volume, dedicated to the findings of the Programme, brings together outputs from all six projects with the aim of ensuring a rapid and widespread dissemination of the Programme's findings. A brief résumé of each of the papers is presented. 4. The papers in this volume cover a wide variety of subjects ranging from ions to the flora and fauna of the United Kingdom. Nonetheless, each study has sought in various ways to quantify observed spatio-temporal patterns at a range of scales, to determine whether those patterns are consistent across scales and to identify the interactions between small-scale patterns and processes and those at larger scales. The importance of the spatial and temporal scales at which studies are conducted, the key role played by dispersal in spatial population dynamics, and the diversity of ways in which large-scale patterns and processes relate to those at smaller scales are highlighted in many of the papers. 4. All of the papers presented here have direct relevance to applied issues. These issues are diverse and include the control of invasive alien species, the conservation of declining, threatened or endangered species, the development of survey techniques, strategies for farmland, woodland and forestry management, and the assessment of pollution sensitivity. Thus, the Thematic Programme has addressed issues of considerable theoretical interest and has at the same time generated results and predictive models that are of considerable practical and policy relevance. [source] Comparative Response to a Survey Executed by Post, E-mail, & Web FormJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 1 2000Gi Woong Yun Recent developments in communication technologies have created alternative survey methods through e-mail and Web sites. Both methods use electronic text communication, require fewer resources, and provide faster responses than traditional paper and pencil methods. However, new survey methodologies also generate problems involving sampling, response consistency and participant motivation. Empirical studies need to be done to address these issues as researchers implement electronic survey methods. In this study we conduct an analysis of the characteristics of three survey response modes: post, e-mail, and Web site. Data are from a survey of the National Association of Science Writers (NASW), in which science writers' professional use of e-mail and the Web is evaluated. Our analysis offers two lessons. First, a caution. We detect a number of potentially important differences in the response characteristics of these three groups. Researchers using multi-mode survey techniques should keep in mind that subtle effects might be at play in their analyses. Second, an encouragement. We do not observe significant influences of survey mode in our substantive analyses. We feel, at least in this case, that the differences detected in the response groups indicate that using multi-mode survey techniques improved the representativeness of the sample without biasing other results. [source] Current Loads of Coarse Woody Debris on Southeastern Australian Floodplains: Evaluation of Change and Implications for RestorationRESTORATION ECOLOGY, Issue 4 2002Ralph MacNally Abstract We evaluated the status of coarse woody debris (CWD, fallen wood) on floodplains of the southern Murray-Darling basin of southeastern Australia. The floodplains are dominated floristically by the river red gum Eucalyptus camaldulensis. Aerial survey techniques were used to estimate the amounts of woody debris within 200 m of the channels along 2,442 km of 11 rivers of the system, including the Murray and Darling Rivers and the Darling Anabranch. Aerially based indices were converted into wood volumes by using ground-truthing at a selection of sites; there was a strong correlation between index values and measured wood volume densities. For thickly forested sites such as Barmah, Gunbower Island, and the Ovens floodplains, the aerial method was not useful, so ground measurements at randomly positioned sites within the forests were used. Volumes were translated into mass by using conversion factors drawn from the literature. We estimated that total tonnage on approximately 221,000 ha of floodplain forests was 4.175 ± 0.579 × 106 tonne. In the larger forested blocks (>7,000 ha), mean wood densities ranged between approximately 12 tonne/ha on the lower Goulburn up to approximately 24 tonne/ha at Barmah State Forest. The area-weighted mean for the entire area was approximately 19 tonne/ha. A main purpose of the research was to place these figures into an historical perspective to evaluate implications for restoration. A thorough search of historical documentation revealed that there are no extant data upon which to estimate pre-European settlement levels. We used information from an apparently undisturbed "unmanaged" site in the Millewa forests of southern New South Wales as a basis. Wood density there corresponded to a mean figure of 125 tonne/ha wood-mass density. By using this figure we estimate that CWD levels on the southern Murray-Darling basin may be of the order of 15% of pre-European settlement levels. Full restoration of the 221,000 ha surveyed would require 23.5 ± 0.579 × 106 tonne, which is equivalent to about 600,000 mature (1 m diameter at breast height) river red gum trees or the amount of timber derived from clear felling about 115,000 ha of river red gum forest at current stocking levels. We discuss the implications of this massive deficit and possible short- and long-term solutions. [source] Combining land cover mapping of coastal dunes with vegetation analysisAPPLIED VEGETATION SCIENCE, Issue 2 2005A. Acosta Abstract Question: Coastal dune systems are characterized by a natural mosaic that promotes species diversity. This heterogeneity often represents a severe problem for traditional mapping or ground survey techniques. The work presented here proposes to apply a very detailed CORINE land cover map as baseline information for plant community sampling and analysis in a coastal dune landscape. Location: Molise coast, Central Italy. Method: We analysed through an error matrix the coherence between land cover classes and vegetation types identified through a field survey. The CORINE land cover map (scale 1: 5000) of the Molise coast was used with the CORINE legend expanded to a fourth level of detail for natural and semi-natural areas. Vegetation data were collected following a random stratified sampling design using the CORINE land cover classes as strata. An error matrix was used to compare, on a category-by-category basis, the relationship between vegetation types (obtained by cluster analyses of sampling plots) and land cover classes of the same area. Results: The coincidence between both classification approaches is quite good. Only one land cover class shows a very weak agreement with its corresponding vegetation type; this result was interpreted as being related to human disturbance. Conclusions: Since it is based on a standard land cover classification, the proposal has a potential for application to most European coastal systems. This method could represent a first step in the environmental planning of coastal systems. [source] Reversing spontaneous succession to protect high-value vegetation: Assessment of two Scottish mires using rapid survey techniquesAPPLIED VEGETATION SCIENCE, Issue 1 2001Andrew R.G. Large Abstract. Despite existing management agreements, significant change has occurred on Carnwath Moss and Coladoir Bog, two mire complexes in central and western Scotland. Spontaneous succession has accelerated, resulting in extensive degradation of the mire vegetation on both sites and, in particular, widespread expansion of Calluna vulgaris - and Molinia caerulea -dominated vegetation types. Vegetation surveys across strong gradients of change were conducted with the aim of quantifying the extent of early (desirable) and late (undesirable) successional vegetation on both sites. For each site multivariate analyses of the vegetation data were carried out using TWINSPAN, which clearly differentiated higher quality and degraded surfaces. In management terms percentage Sphagnum cover can act as a useful proxy measure of water level and shrub layer height can also serve as a useful indicator of the degree of degradation. A broad-based, five class condition continuum was developed for the Carnwath Moss site. While such an assessment scheme is a somewhat arbitrary means of allocating mesotope areas to specific condition classes, it is rapid to apply and simple enough to be applied by a range of users. A drawback is that the methodology is data-light in temporal terms and is not a long-term substitute for properly-funded monitoring programmes for important sites. For both mires, recommendations are made for management with the main emphasis being on maintaining water tables at appropriate levels to maximise the floristic diversity of active mires. [source] The role of integrated geophysical survey methods in the assessment of archaeological landscapes: the case of PortusARCHAEOLOGICAL PROSPECTION, Issue 3 2009Simon Keay Abstract The regular application of geophysical, geochemical and topographical survey techniques to evaluate archaeological sites is well established as a method for locating, defining and mapping buried archaeological materials. However, it is not always feasible to apply a range of different methods over a particular site or landscape due to constraints in time or funding. This paper addresses the integrated application of a variety of survey techniques over different sites and landscapes in Italy and elsewhere, focusing on the recent results from the ongoing survey and excavations at Portus, the port of Imperial Rome. An integration of methods, including magnetometry, resistance survey, ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) has been used at the site to fulfil a number of different research objectives. Results of the magnetometer survey have successfully recorded the nature and extent of archaeological material over an area of 220,ha, allowing a plan of the port and related structures to be produced and variations in archaeological potential across the entire landscape to be assessed. The integration of several techniques in one area of the site between the Porto di Claudio and the Porto di Traiano has mapped the structural remains of this area of the port prior to and during investigation of the zone through excavation. Current work on the geophysical survey data, using different software programs for the processing of survey data and merging different datasets using geographical information system packages, has allowed the results of the work to be visualized and presented to archaeologists in a comprehensive and unambiguous fashion, facilitating the future management and preservation of the site. In addition ongoing research is using different statistical and visual methods of integration to refine the archaeological interpretation of the study area. Copyright © 2009 John Wiley & Sons, Ltd. [source] Thermally activated mineralogical transformations in archaeological hearths: inversion from maghemite ,Fe2O4 phase to haematite ,Fe2O4 formARCHAEOLOGICAL PROSPECTION, Issue 3 2006David Maki Abstract A series of laboratory experiments were conducted in an effort to understand why magnetic field gradient survey techniques failed to detect hearths at a prehistoric archaeological site in southern California. The study used various methods of environmental magnetism to examine the effects of exposing soil samples to a temperature of 650°C over a period 26,h. Results of the study indicate that the failure was associated with a reduction in soil magnetic susceptibility to below background levels within hearth soils. This reduction was due to high-temperature transformation of iron oxides from a highly magnetic form to a relatively non-magnetic form. The reduction in susceptibility is thought to have proceeded via the oxidation of primary (lithogenic) magnetite, Fe3O4 to maghemite, ,,Fe2O4 followed by the inversion of maghemite to haematite, ,Fe2O4. The study suggests that in some instances high temperature inversion can reduce the proportion of ferrimagnetic minerals within a hearth to below initial concentrations (resulting in a negative magnetic field gradient anomaly, the opposite of what is normally expected). A field experiment was also conducted to determine what soil temperatures might be achieved 2,cm beneath a hearth. The experiment recorded temperatures ranging from approximately 400°C to 650°C, with an average temperature of about 470°C. Soil colour changes and magnetic susceptibility enhancement observed at the conclusion of the field experiment indicate that these temperatures were sufficient to activate some mineralogical changes, possibly including inversion to haematite. The implications of high temperature inversion to archaeological prospection are discussed, as is a potential archaeological application. Copyright © 2006 John Wiley & Sons, Ltd. [source] Geophysical surveys at King Lobengula's Palace KoBulawayo, ZimbabweARCHAEOLOGICAL PROSPECTION, Issue 1 2005C. Gaffney Abstract This report covers the application of magnetic survey, primarily using a magnetic susceptibility field instrument, at the historically attested site of KoBulawayo, Zimbabwe. The approximate position of the site was known before the geophysical survey took place; it was believed to comprise a Royal Enclosure, a surrounding open space possibly used as a military parade ground and the Commoner/Peripheral Settlement of Lobengula, King of the Ndebele. Occupation at the site was short lived and after only 11 years the capital of the Ndebele state was destroyed by fire in 1881. A pilot survey was undertaken in 1994 to assess the suitability of survey techniques. Consequently, a second, more extensive survey was carried out in late 1996 and early 1997 with the intention of delimiting the Royal Enclosure. Further periods of data collection took place later in 1997 and in 1998. This report describes the methods used and the interpretation of the geophysical results in the context of the understanding and management of this important historical site. Additionally, some of the results of the geophysical work have been tested by excavation and a discussion of the correlation between these data sets is also reported in this article. Copyright © 2004 John Wiley & Sons, Ltd. [source] The influence of waterlogging and variations in pedology and ignition upon resultant susceptibilities: a series of laboratory reconstructionsARCHAEOLOGICAL PROSPECTION, Issue 2 2004D. G. Weston Abstract Magnetic survey techniques, such as fluxgate gradiometry, depend greatly on bodies of soil developing enhanced magnetic susceptibilities. Coarse mineral soils, especially those subject to a high groundwater table, often fail to develop enhanced susceptibilities and gradiometry. An example of this is Easingwold, in the Vale of York, UK. Gradiometry detected very little, however, subsequent excavation uncovered a complex of features suggesting multiphase activity and evidence for industry. This non-detection is attributed to the coarse mineral soils and the high watertable. Several laboratory reconstructions were made to investigate the influence of specific characteristics of soil and ignition episode upon susceptibility. It was found that variations in soil texture had marked impacts on the levels of susceptibility attained, as did waterlogging. Leaching had a limited effect upon soil magnetic susceptibility, but there was variation according to texture. Copyright © 2004 John Wiley & Sons, Ltd. [source] Comparison of geophysical techniques for investigating an infilled ditch at Bury Walls hill fort, ShropshireARCHAEOLOGICAL PROSPECTION, Issue 4 2003R. E. Murdie Abstract Five geophysical survey techniques were used to investigate the infilled section of the outer ditch at the Iron Age hill fort of Bury Walls, Shropshire. The techniques were resistance mapping and four profiling methods: resistivity sounding, ground-penetrating radar (GPR), P-wave seismic refraction and S-wave seismic refraction. The ditch was clearly visible on the resistance map and on GPR profiles, but no depth estimate was obtainable from these surveys. The most successful survey technique was S-wave seismic refraction, both for determining whether the ditch was present on a profile and for obtaining an estimate of its depth. A key factor for the success of S-wave seismic refraction profiling was that the ditch had been excavated into the sandstone bedrock. Copyright © 2003 John Wiley & Sons, Ltd. 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