19 research outputs found
Forest ecosystem research in Hainich National Park (Thuringia) : first results on flora and vegetation in stands with contrasting tree species diversity
No full textA floristic description is presented of the study sites of the Research Training Group “The role of biodi-versity for biogeochemical cycles and biotic interactions in temperate deciduous forests”. To investi-gate different aspects of plant biodiversity in Hainich National Park (Thuringia), deciduous forest stands with low, medium and high canopy tree species diversity were compared. The results of species richness and forest communities show that the research sites are characterised by a typical central European forest flora. Greater vascular plant species richness occurs with higher diversity of tree species. Six of altogether twelve research sites are assigned to the beech forest alliance (Galioodorati-Fagion), the second half belongs to the oak-hornbeam forest alliance (Carpinionbetuli). Suballiances within the Galioodorati-Fagion in the study area include the Galio-Fagetum and the Hordelymo-Fagetum. All Carpinionbetuli relevées are assigned to the suballiance Stellario-Carpinetum
Waldökologie online, Heft 3 (2006)
No full textDiesmal konnten Sie auf unserer Homepage (www.afsv.de) mitverfolgen, wie Heft 3 langsam bis zu seiner Endversion gewachsen ist. Mit unserer neuen Rubrik "Vorabveröffentlichungen" haben wir uns von der starren Jahrbuch-Periodik gelöst. Es gibt keinen offiziellen Redaktionsschluss mehr. Manuskripte, die bereits frühzeitig im Jahr eingereicht werden und ein erfolgreiches Review- Prozess durchlaufen, stehen i.d.R. acht Wochen später online. Sobald 100 Seiten Umfang erreicht sind, ist automatisch ein neues Heft abgeschlossen
Tectonic deformation in the Santorini volcanic complex (Greece) as inferred by joint analysis of gravity, magnetotelluric and DGPS observations
No full textTectonic activity is very difficult to study in the Santorini volcanic complex (SVC) as it comprises a cluster of small/awkwardly shaped islands covered by pyroclastic deposits from which tell-tale markers are swiftly erased, while seismicity is generally absent. We address the problem by combining geophysical exploration methods to evaluate the long-term effects of tectonic deformation and time-lapse differential GPS to directly evaluate the magnitude and kinematics of present-day deformation. The former comprise 3-D gravity modelling to investigate the footprint of tectonics on the pre-volcanic Alpine basement and natural-field EM induction to map conductivity anomalies epiphenomenal to fluid circulation in faults. Our analysis identified the following principal tectonic elements: The Trans-Santorin Divide (TSD), a segmented NNW-SSE dextral strike-slip fault splitting the SVC sideways of the line joining Cape Exomytis, the Kammeni Islets and the Oia-Therassia Strait. It is collocated with a major vertical conductive zone and forms a series of dents and depressions in the basement. The Columbo Fault Zone (CFZ) is a pair of parallel NE-SW subvertical normal-sinistral faults straddling the northern SVC and terminating against the TSD; it may be associated with fluid injection into the shallow crust but appears to have limited effect on crustal conductivity (compared to TSD). The Anhydros Fault Zone (AFZ) is detected by its footprint on the basement, as a set of parallel northerly dipping NE-SW faults between the Athinios-Monolithos line and Fira. If it has any heave, it is left-lateral. It does not have distinguishable electrical signature and does not contribute to present-day horizontal deformation. The CFZ and AFZ are antithetic and form a graben containing the volcanic centre of Kammeni Islets. E-W extension was identified lengthwise of a zone stretching from Cape Exomytis to Athinios and along the east flank of the caldera to Imerovigli. N-S normal faulting confirmed therein, may have contributed to the localization of the east caldera wall. NNE-SSW compression was observed at SW Thera; this may have produced E-W failure and contributed to the localization of the south caldera wall. The footprint of the caldera on the basement is a parallelogram with N-S long and WNW-ESE short dimensions: if the east and south flanks collapsed along N-S normal and E-W inverse failures, then the west and north flanks may have formed analogously. Present-day deformation is localized on the TSD and CFZ: this can only be explained if the former is the synthetic (dextral) Riedel-R shear and the latter the antithetic (sinistral) Riedel-R′ shear, generated by N-S σ1 and E-W σ3 principal stress axes. Accordingly, NW-SE right-lateral shearing of the broader area is expected and indicated by several lines of indirect evidence. The geographic extent of this shearing and its role in the regional tectonics of the south Aegean remains to be confirmed and appraised by future research. Contemporary volcanic centres develop at the interface of the TSD with the CFZ/AFZ graben; volcanism appears to be controlled by tectonics and the SVC to be shaped by tectonic rather than volcanic activity. © 2019 The Author(s). Published by Oxford University Press on behalf of The Royal Astronomical Society
Application and comparison of three tomographic techniques for detection of decay in trees
Get PDFThis paper reports application of electric, ultrasonic, and georadar tomography for detection of decay in trees and their comparison with the traditional penetrometer. Their feasibility in arboriculture is also evaluated, critically considering some "open problems." The experiments were carried out in an urban environment on two plane (Platanus hybrida Brot.) trees. Both trees, after felling, showed extensive white rot in the central cylinder. The electric tomography revealed low resistivity zones roughly centered in the trunk. A comparison with the successively cut sections showed a fine correspondence to decayed areas and a strong correspondence between high moisture zones and low resistivity zones. Ultrasonic tomography demonstrated to be a very effective tool for the detection of internal decay, accurately locating the position of the anomalies and estimating their size, shape, and characteristic in terms of mechanical properties. With the georadar technique, the high contrast of electromagnetic impedance measured between the inner decayed section and the outside sound section allowed the detection of the interface between the sound and decayed section of the tree, using radar acquisition in reflection modality. The penetrometer profiles detected the low-resistance areas inside the two trunk
Aurora Australis Voyage 6 (FISHOG) 1991-92 Heard Island Fish Data
No full textProgress Code: completedStatement: These data follow on from that of the 1990 winter cruise (HIMS). Sampling was carried out using a 35m headline length bottom trawl. Stations were chosen using a random stratified survey design, stratified according to depth: 0-100m, 100-200m, 200-300m, 300-500m. Sixty-nine trawls were completed successfully.
All fish were identified, weighed and measured on board, except specimens too small to weigh accurately, which were frozen for later weighing in the Antarctic Division laboratories. For all common species, guts, gonads and otoliths were removed from 25 specimens of each species per haul (if numbers permitted). For large catches of individual species, a random subsample of 50 was individually weighed, measured and guts gonads and otoliths removed, a further 50 were weighed and measured, and a further 100 were measured. The total number and weight of each species was also recorded.
At some sites, samples of liver, heart and muscle of Dissostichus eleginoides were taken and stored in liquid nitrogen for the mitochondrial DNA (mtDNA) study.
CTD data were collected at most stations, so fish data and oceanography data are consistent. Position, date and time of each station was recorded, and tabulated results, a cruise track, and a station map is included in the reference given above.The data associated with this record is accessible via the parent record - https://data.aad.gov.au/metadata/Historical_Fish_data<br/><br/>This dataset contains the data from Voyage 6 (FISHOG) 1991-92 of the Aurora Australis. The observations were taken from the Heard Island area in January and February 1992. The data contains temperature and salinity data from a CTD survey and the results from demersal fish trawl surveys. The major species were Dissostichjus eleginoides, Channichthys rhinoceratus, Channichthys gunnari, Lepidonotothen squamifrons, Gymnoscopelus nicholsi and Paradiplospinus gracilis. This is a subset of the data for the whole voyage. The objectives of the fish program were: to assess the distribution and abundance of demersal fish on the shelf in the AFZ around Heard Island; to investigate the biology of the more important species.<br/><br/>A Microsoft Access database containing data from this cruise, plus several others is available for download from the provided URL. The Entry ID's of the other metadata records also related to this data are:<br/><br/>AADC-00038 <br/>AADC-00068<br/>AADC-00073<br/>AADC-00075 <br/>AADC-00080 <br/>AADC-00082 <br/>c88_data<br/><br/>The fields in this dataset are:<br/> <br/>Cruises<br/>Date<br/>Location<br/>Latitude<br/>Longitude<br/>Species<br/>Gear<br/>Length<br/>Weight<br/>Sex<br/>Gonad<br/>Eye<br/>Otolith<br/>Stomach<br/>Lifestage<br/>Famil
The 1992 Wintering Field Season at Heard Island
No full textProgress Code: completedStatement: See the report for further details on individual projects.
Editors Note:
The following report was written as a repository of observations and data collected on the 1992 Heard Island wintering expedition. It was designed to be ready for dissemination by no later than four weeks after the return of the expedition to Australia. As such it contains segments which are essentially first drafts of scientific papers some written before all the data were available and most written without access to the latest scientific literature (the mails were particularly bad at Heard Island). As such, some of the conclusions and opinions may have changed in the light of later data not used in this report, or on sighting scientific papers unseen at the time of writing. Those sections marked with an asterik are first drafts and before quoting from this report the reader should, in the interests of accuracy, check with the author or the final published paper. I would like to thank John Cox and Simon Wright for their help in drawing figures and Pat Quilty and Mary Green who helped with the proof reading.1992 Wintering Field Season at Heard Island.<br/><br/>Taken from the report:<br/><br/>Genesis of the Expedition<br/>The concept of the 1992 expedition arose from the need to gain access to animals at Heard Island for research at precise times of the year to deploy and retrieve time-depth recorders. An Antarctic Science Advisory Committee workshop on the Southern Ocean Ecosystem was held on 10-11 September 1989 to discuss future plans for ANARE areas of operation. The workshop was attended by myself (KG - Ken Green) and Harry Burton (HRB) for the Land-based Biology section. It became apparent that the two consecutive summers needed to deploy and retrieve the recorders (one leaving Heard Island in the autumn, the next arriving early in the spring) could not be accommodated in the planning process because of planned commitments in the eastern sector of the Australian Antarctic Territory. The suggestion was therefore made by us that if two summers were impossible then perhaps the best solution was a wintering party. A memo to this effect was drafted by us and submitted on 26 September 1989. This was considered at a Heard Island Committee meeting on 18 October 1989 when changes to the shipping program were suggested that would allow two consecutive summers on Heard Island and it was concluded that "this arrangement should.....negate the need for a wintering program in the near future".<br/><br/>The suggested rearrangement did not fully match the times required and the Land-based Biology section was loathe to deploy equipment in one summer without guaranteed access to the animals in the following spring. It was felt that this could only be assured if the biologists were on the island through the whole period. An additional advantage was that dietary studies of the main fish predators could be continued throughout the winter period. To this effect the proposal for a wintering party was re-submitted on 26 February 1990 with the suggested personnel being three biologists and three people in support. The proposal was re-submitted in more detail on 4 May 1990 and was examined by the ANARE Annual Planning Committee who referred it to the Assistant Director (Science) to "examine the options for conduct of this program and that following this the Heard Island Planning Committee and to the Assistant Director (Science) who was requested to prepare a paper for distribution to committee members for consideration at a meeting to be held on 17 July 1990.<br/><br/>At this point the maiden voyage of the Aurora Australis took place with one aim being to deploy a party of four on Heard Island for a period of one month to undertake research into seals and penguins. This party included two of the subsequent wintering party (see Green 1990). This expedition returned in time for the Heard Island Planning Committee meeting which was held to hear reports on the 1990 expedition and to consider the proposals for 1993. A reduced complement of four expeditioners was suggested in a proposal appearing under the signature of the acting Assistant Director (Science). The committee voted to forward the proposal to the ANARE Annual Planning Committee on 26 July 1990 with the suggested alteration in timing so that the wintering expedition occurred in 1992 rather than 1993 to avoid clashing with science requirements for the Lambert Traverse.<br/><br/>The ANARE Annual Planning Committee referred the matter to the executive and on 27 August 1990 the Heard Island Planning Committee agreed to "support a limited winter program on Heard Island in 1992 on the condition that it is to be a purely land-based exercise with work restricted to the Spit Bay area" with "a final decision on the conduct of a Heard Island wintering program (to) be made by the Executive in the near future.". Approval was given at the Heard Island Committee meeting of 24 September 1990, subject to approval by the Antarctic Research Evaluation Group (AREG) of the major programs suggested by the Land-based Biology section. At the Heard Island Planning Committee meeting of 12 December 1990 it was confirmed that AREG had provisionally approved the Land-based Biology programs and that the Executive "have supported the program subject to ASAC endorsement of the three proposals put forward."<br/><br/>At this stage the Heard Island expedition was expected to proceed on that basis with additional programs to be considered by AREG. From this point the expedition had sufficient momentum to keep going and subsequent meetings of the Heard Island Committee dealt mainly with questions of logistics, infrastructure and procedures (these are covered in Antarctic Division file number 89/754). The final composition of the personnel for the party was not settled until 14 October 1991. The expedition sailed from Hobart on 8 January 1992 on board the Aurora Australis.<br/><br/>Assessments of the possibility of landing by zodiac at Spit Bay were made on 24 and 28 January and on 28 January the party was deployed at Atlas Cove using three inflatable rubber boats. For a narrative of the expedition see the Log (later in the report).<br/><br/>Scientific Background<br/>A commercial Soviet fishery has existed in the Iles Kerguelen region from the early 1970s and catches averaged about 20,000 tonnes per year between 1979 and 1986, dropping to 7886 tonnes in 1987 and 773 tonnes in 1988. Before 1978, the benthic species Notothenia rossi and N. squamifrons were mainstay of this fishery. The icefish, Champsocephalus gunnari increased in importance after that to constitute the majority of the catch. There has been little commercial fishing around Heard Island, and none since a 200 nautical mile Australian Fishing Zone (AFZ) was declared in 1979 (Williams and Ensor 1988). Catches of icefish by the Soviet research vessel RV Professor Mesyatsev on banks to the north-east of Heard Island indicated concentrations of this species in commercial interest, but other species, including benthic fishes also occurring in the diet of the seals, are not sufficiently abundant for commercial interest at this time (Williams and Ensor 1988). Results from the 1987/88 Heard Island ANARE suggested that there was a potential for competition between the increasing numbers of Antarctic Fur Seals and any future commercial fishery (Green et al 1990). Winter data were, however, lacking. In 1990 the first ANARE expedition to be present on the island into the winter period since the 1954 wintering expedition took place, with the main program being an attempt to examine the winter diet and feeding areas of Antarctic Fur Seals. Subsequent assessment of the diet of Southern Elephant Seals comparing Macquarie and Heard Islands (Green and Burton in press) also showed this species to be a potential competitor, both with Antarctic Fur Seals and with a potential fishery.<br/><br/>Bearing in mind the possibility that a request for commercial fishing rights within the Heard Island AFZ might be made in the foreseeable future, probably as an adjunct to the Kerguelen or Antarctic fishery rather than a new venture, a full assessment of the role of fish predators was indicated. The analysis of a potential interaction between wildlife and fisheries depends on the collection of three primary sets of data: the availability of commercial fish species, the diet of the predator, and the spatial overlap in the demands of the two competing interests. The aim of the 1992 ANARE was therefore to collect all of these data. The Marine Science cruises to the area collected data on fish location and relative abundance, continuing the work of previous voyages such as Professor Mesyatsev and the Aurora Australis on its maiden voyage. The work of the shore party would be to investigate the diet of fish predators through scat collections and examination of stomach contents. The main objectives of the 1992 ANARE program on Heard Island were therefore to collect data on the feeding ecology of the major warm-blooded predators of fish in the Heard Island region (excluding whales), to provide baseline data in their ecology in the absence of a nearby fishery, and to provide an estimate of the degree of interaction between these animals and a potential fishery. This was considered to be a major scientific program, both in resources and time and was expected to net valuable scientific information from a very small deployment of personnel. In addition to the main objectives, a number of additional research programs were to be conducted by the wintering party including meteorological observations, glaciology, coastal erosion surveys and marine debris surveys.<br/><br/>Field Party<br/>Erwin Erb, Medical Officer<br/>Ken Green, Biologist<br/>Geoffrey Moore, Biologist<br/>David Slip, Biologist<br/>Attila Vrana, Enginee
Forest Ecology, Landscape Research and Nature Conservation, Issue 9 (2010)
No full textHeft 9 von WLN (Waldökologie, Landschaftsforschung und Naturschutz – Forest Ecology, Landscape Research and Nature Conservation) bietet ein breites, facettenreiches Themenspektrum aus den Bereichen Standorts- und Vegetationskunde, Modellierung, Biodiversitätsforschung sowie Artenschutz. In der neuen Ausgabe werden einmal mehr vielseitige Möglichkeiten aufgezeigt, aktuellen Fragestellungen im In- und Ausland mit innovativen Methodenansätzen nachzugehen
Report on the 1990 expedition to Heard Island - Ken Green
No full textProgress Code: completedStatement: The quality of the scanned pages may vary. An OCR process has been run over the document.This is a scanned copy of the report on the 1990 expedition to Heard Island, edited by Ken Green.<br/><br/>Taken from the report:<br/><br/>The 1990 ANARE to Heard Island was an opportunistic visit as a result of the delayed delivery of the RSV Aurora Australis, and the consequent decision to concentrate the marine science cruise around Heard Island rather than in Prydz Bay. This was the first ANARE to be present on the Island into the winter period since the 1954 wintering expedition, and the only expedition to spend an extended time in autumn/winter at Spit Bay since sealing days in the 1840s to 1920s.<br/>The focus of the field work was biological, with the main program being an attempt to examine the winter diet and feeding areas of Antarctic Fur Seals. Results from the 1987 /88 Heard Island ANARE suggested that there was a potential for competition between the increasing numbers of Antarctic Fur Seals and any future commercial fishery. The 1990 ANARE set out to see if in fact the winter diet of the fur seals included commercial fish species and sizes, and if the seals foraged in potential commercial fishing grounds.<br/>The Antarctic Fur Seal population on Heard Island is increasing exponentially. This increasing population feeds on the fish resources around Heard Island (Green et al. 1989). A commercial Soviet fishery has existed in the Iles Kerguelen region from the early 1970s and catches averaged about 20,000 tonnes per year between 1979 and 1986, dropping to 7886 tonnes in 1987 and 773 tonnes in 1988. Before 1978, the benthic species Notothenia rossii. and N. squamtfrons were the mainstay of this fishery. The icefish, Champsocephalus gunnari increased in importance after that to constitute the majority of the catch. There has been little commercial fishing around Heard Island, and none since a 200 nautical mile Australian Fishing Zone (AFZ) was declared in 1979 (Williams and Ensor 1988). Catches by the Soviet research vessel RV Professor Mesyatsev of icefish on banks to the north-east of Heard Island indicated concentrations of this species of commercial interest, but other species, including benthic fishes also occurring in the diet of the seals, are not sufficiently abundant for commercial interest at this time (Williams and Ensor 1988). Regulations, including mesh size restrictions, limit the size of icefish taken by trawlers around Iles Kerguelen to fish longer than 280 mm. As the bulk of the summer diet of seals consists of subadult icefish less than 240 mm in length (Green et al. 1989), there would, at first consideration, appear to be little direct competition for fish in summer. This appears to be a similar situation to that in the South Atlantic sector, where Doidge and Croxall (1985) suggested that competition between commercial fisheries and Antarctic Fur Seals may not be acute, as trawlers took mainly adult N. rossii , whereas the seals took mainly juveniles. However, it is obvious that considerable catches of any size class by either seals or a fishery will have future effects on all size classes.<br/>It is to be expected that a request for commercial fishing rights within the Heard Island AFZ will be made in the foreseeable future. Examination of research fishing catches around Heard Island and the diet of Antarctic Fur Seals indicated a potential conflict between any future fishery and the fur seal population (Green et al. 1989). The analysis of a potential interaction between wildlife and fisheries depends on the collection of three primary sets of data: the availability of commercial fish species, the diet of the predator, and the spatial overlap in the demands of the two competing interests. The aim of the 1990 ANARE was to collect all of these data. The Marine Science cruise would collect data on fish location and relative abundance, and the shore party would investigate the diet of the predators through scat collections. The spatial overlap between foraging area and potentially commercial fish stocks was to be examined by the use of radio tracking. both from the ship and from shore. Radio location was planned to determine the foraging range of Antarctic Fur Seals (and King Penguins), using one fixed receiver (at Scarlet Hill), and one mobile receiver (Aurora Australis) for triangulation.<br/>The planning of this project began when the location of the Marine Science cruise for 1989/90 was moved from Prydz Bay to Heard Island, because of the late delivery of the RSV Aurora Australis . A proposal was put to ASAC for a shore-based component of the fisheries study on 23 April 1989 and received AREG backing on 27 July 1989. Executive approval was given on 2 August 1989. After some withdrawls due to the lateness of the expedition the composition of the party was finalised on 12 February 1990 (see below). Other studies proposed were the feeding ecology of King Penguins (also piscivores). while projects to collect data on attendance behaviour, growth rate and weaning weight of fur seals could not be collected because of the lateness of the expedition. Smaller projects, added at the planning stage, included the collection of flotsam and the re-examination of archaeological sites in the Spit Bay area, particularly Oil Barrel Point, to examine the extent of damage due to beach erosion and weather.<br/>The party of four was deployed at Spit Bay camp on a calm sunny day on 22 May 1990. This was the first deployment of an ANARE party by the Aurora Australis. and the landing by rubber boats onto the rocky Spit Bay shore went well. The old leaky aircraft crate hut and the Apple hut were showing their age and lack of maintenance. The hut was more undercut by wave action than during previous visits, and the Apple was losing sheets of insulation through flaking. Thankfully the Apple didn't leak and provided a relatively dry retreat from the sometimes very wet conditions in the tents in the weeks to come.<br/>Despite difficulties in gaining access to a high spot for radio tracking. most of the planned work was successful. The radio transmitters were attached to 30 Antarctic Fur Seals using only physical restraint, despite the size of some of the larger bulls. The collection of Antarctic Fur Seal dietary material in just one month equalled that collected by the 1987/88 ANARE in six months. A complete census was undertaken of seals and birds from Compton Lagoon on the north coast to the Gotley Glacier on the south coast. At the same time, plastic and metal debris was collected from the coast and proved to be mainly fisheries related. There was a surprisingly high number of animals on Heard Island; with about 1700 Antarctic Fur Seals and 4500 Southern Elephant Seals present on the eastern end of the Island. The number of animals suggests that there would be plenty to occupy a full wintering party in the future. Of the Southern Elephant Seals present, two had been tagged at Davis only three to four months previously. It had been believed previously that animals migrated to Davis for the moult after the breeding season and then didn't return to the Island until the next breeding season. The rapid return of these animals to Heard Island poses questions as to when and where many of these seals feed.<br/>Other work undertaken included the keeping of meteorological records, the documentation of coastal erosion and deterioration of sealing sites, collections of animal specimens, and glaciological work. The glaciological work included transects with regular measurements of altitude. Horizontal recession of glacier margins has been reasonably well documented, but quantitative data on volumetric changes to glaciers also requires a measurement of the vertical recession. The work completed on this ANARE will act as baseline data for future studies.<br/>Collections were also made of Antarctic Fur Seal skulls to examine the age-specific mortality on the Island; sub fossil King Penguin bones were collected for carbon dating and a large, complete whale skull which was found on the Spit was returned to Australia. Unfortunately some of these samples were lost during the retrieval of the party.<br/>The field work came to an end four days ahead of schedule, on 17 June. Six boat loads of equipment were ready for removal, but deteriorating weather conditions after five boat loads had been removed meant that the last load was left behind in favour of an attempt to take off the shore party. In the course of this trip the Zodiac was swamped and rolled in the surf with all aboard reaching shore safely. The ANARE Zodiac was finally abandoned and the shore party was taken off the Island a second time in one of the Zodiacs from the RSV Aurora Australis, thus ending an eventful and scientifically successful expedition
