1,721,000 research outputs found
Monitoring data of key benthic reef species in the Cape Rodney-Okakari Point (Leigh) Marine Reserve and at adjacent fished sites: 1999-2019
No full textThe Cape Rodney-Okakari Point Marine Reserve is New Zealand's oldest no-take marine reserve situated along the Leigh coast (est. 1978; the 'Leigh Marine Reserve' hereafter). Historic information on rocky reef communities in the Leigh Marine Reserve is available from baseline surveys in 1978 (Ayling 1978) and repeated in the 1990s (Babcock et al. 1999). While these provide valuable information on long-term changes in the reserve, they did not include fished reefs outside the reserve that provide a control for the effect of protection. The monitoring program presented here was established in 1999 by N. Shears (University of Auckland) for the New Zealand Department of Conservation and includes four sites inside and four sites outside the Leigh Marine Reserve (Shears and Babcock 2003). At these sites, the reefs are gradually sloping from the intertidal to the reef edge, occurring at ~8–15 m depth. From 1999–2000 the reefs were surveyed in four depth ranges (10 m), but subsequent sampling has focussed on the 4-6 m depth range as this is representative of the depth range where sea urchins (Evechinus chloroticus) are most abundant and can form barren habitat (Shears & Babcock 2003; Shears et al. 2008). This depth range has been sampled sporadically (every 1–3 yr at these sites since 2001; note that only fished sites were surveyed in 2003). The surveys were conducted on SCUBA, and at each site, five 1-m2 quadrats were haphazardly sampled within the 4–6 m depth range. Within each quadrat, the density (the number of individuals per metre square) of sea urchins and all large brown macroalgae were recorded (e.g. Ecklonia radiata, Carpophyllum spp., Cystophora spp. and Sargassum sinclairii). For sea urchins, behaviour was recorded as 'cryptic' (sea urchins found in holes, cracks or crevices) or 'exposed' (sea urchins are out in the open and have a strong impact on macroalgal communities; Spyksma et al. 2017). For all large macroalgae the length of all fronds was measured to the nearest 5 cm using a measuring tape. For E. radiata, measurements were taken for both stipe and total length (i.e. from the top of the holdfast to the meristem and the distal end of the primary lamina, respectively). The percent cover of crustose coralline algae, bare rock, turfing algae (e.g. articulated coralline, red foliose), filamentous algae and sediment was assessed visually in each quadrat. In cases where filamentous algae were recorded as overlaying turf and encrusting algae, such that total cover exceeds 100%, the cover data was standardised to add up to 100%
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Marine Reserves, Fisheries and the Spiny Lobster Jasus edwardsii
No full textResearch in north-eastern New Zealand marine reserves has provided valuable insights into spiny lobster (Jasus edwarsii) behaviour, movement, and reproduction and demonstrated how reserves can allow recovery of lobster populations and contribute to spill-over fisheries. However, over the last 20 years lobster populations in these reserves have undergone considerable declines, raising questions around the effectiveness of reserves in protecting populations from fishing. This thesis examines the effectiveness of two north-eastern New Zealand marine reserves in protecting lobster populations and investigates the drivers and implications of long-term declines in lobster within these reserves. This was assessed using an analytical approach applied to dive and potting survey data, and tag-recapture data, collected within and adjacent to both reserves. The status of fished stocks in the study area was assessed using reserve populations as unfished controls. This analysis estimates spawning stock and biomass in fished areas was 2-3% of unfished levels, which is considerably lower than fishery estimates of stock status. Novel analytical approaches were used to analyse gradients in catch rates across reserve boundaries and found limited evidence of edge effects and spill-over. In addition, seasonal potting caught few lobster on offshore soft-sediment habitats and there were no tag-recaptures on or near offshore boundaries. Seasonal offshore movements were mostly limited to movements between shallow and deep reef, and young adult males undertaking nomadic longshore movements were the main demographic caught in adjacent fisheries. These results contrast previous reports which describe spill-over across the offshore boundaries and likely reflect comparatively lower population densities. The harvest of lobster undertaking seasonal movements beyond offshore boundaries is believed to have contributed to population declines as populations throughout the reserves were impacted by fishing. In addition, this fishing is believed to have reduced resilience of these populations to an extended period of low recruitment. Overall, these results highlight the poor state of the wider fishery and suggest that while the reserves examined still play a role in protecting lobster, they are too small to fully protect lobster populations. The results and methods developed provide important information that can inform both future marine reserve design and fisheries management
The extent of kina barrens over time at Hauturu-o-Toi and the Noises Islands
No full textKelp forest habitats are the foundation for many species found on temperate rocky reefs. With fishing pressures decreasing populations of key urchin predators, the issues of urchin (kina) barrens and deforestation of kelp beds have become more prevalent. Satellite and aerial imagery were used to map the extent of kina barrens surrounding Hauturu-o-Toi and the Noises Islands in the Hauraki Gulf, northern New Zealand. GIS mapping software was used to digitise images from 1953, 1979 and 2019 for Hauturu-o-Toi, and for 1978 and 2019 for the Noises. This allowed a large-scale assessment of the current extent of kina barrens in each location and long-term changes in the extent of kina barrens at key locations.
Aerial imagery and historic descriptions indicate that kina barrens did not occur in either location in the 1950’s but by the 1970’s kina barrens were a major habitat on subtidal reefs: covering 11.6% of reef at Hauturu-o-Toi and 23.97% at the Noises. This progression is consistent with industrial scale removal of predators, such as the spiny rock lobster and snapper, in the middle of last century. The extent of barren found to cover the reef habitat at the Noises increased between 1979 (24.0%) and in 2019 (49.5%) demonstrating that kina barrens are now a major habitat on the inner gulf reefs. This is contrary to much of the previous literature which claimed that the inner gulf was not subject to the issue of kina barrens to the extent that outer gulf islands were.
Urchin barren covers 32.73% of reef habitat at Hauturu, dominating a shallow band around much of the island, but most extensive on the more wave exposed northern and eastern coasts. There was a positive relationship between the extent of kina barrens and wave exposure, with overall barren coverage and the lower depth of barrens increasing with exposure.
The accuracy of habitat maps produced ranged from 67.9% to 79.5%, falling within the range of accuracies found in studies using similar methods, scope and detail. These habitat maps provide a clear visualisation of both how barren extent has changed over time, and where barren is to be found at each site. With marine protected areas (MPA’s) proposed for both locations, these habitat maps and the methods used provide an efficient and effective tool for monitoring future change in the extent of kina barrens and kelp forests on shallow reefs
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