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Water Quality, Ecology, and Evaluation of a Rapid Algae Monitoring Technique in Human-Controlled Water Bodies
No full textIncreasing urbanization worldwide has led to increased water body alterations, including the discharge of effluent into aquatic ecosystems. As the world’s population continues to grow, the development of new wastewater treatment plants will be crucial and the discharge of effluent into water bodies will increase. Despite this growing trend, the impacts of effluent on receiving water bodies are still relatively poorly understood. This dissertation (1) reviews the effects of effluent input into streams across the globe, (2) examines how water quality in effluent-dependent streams varies spatially and temporally in Arizona, and (3) tests a potential new rapid water quality monitoring technique for better management of these systems. Across the globe, effluent inputs generally impaired water quality in streams near effluent discharge points. The majority of ecological studies reviewed found that basal resources, aquatic invertebrates, and fish were negatively affected in a variety of ways (e.g. biodiversity losses, replacement of sensitive with tolerant species). However, several studies showed the importance of effluent in providing environmental flows to streams that had been dewatered by anthropogenic water withdrawals, especially in semi-arid and arid regions. Our study of effluent-dependent streams in Arizona indicates that conditions may be stressful for the most sensitive taxa at sites closest to effluent outfalls (e.g. elevated temperature and nutrient level), especially in summer. However, overall, these streams have the capacity to serve as refuges for native biota in Arizona. Furthermore, they may become the only aquatic habitat available in many urbanizing arid regions. The combination of elevated temperatures and nutrient levels we observed closest to effluent outfalls could lead to increased frequent algal blooms. Our evaluation study of a hand-held fluorometer to measure chlorophyll-a as an indicator for potential harmful algal bloom demonstrated that the probe is not sensitive to ambient light, performed well at low chlorophyll-a concentrations (< 25 µg/L) across a range of turbidity levels (50 to 70 NTU), and with some adjustments would be useful for monitoring in effluent-fed streams or other water bodies. Although effluent-fed streams were historically of lower quality than natural streams, newer treatment techniques can result in high quality water and support numerous native species and diverse ecosystems despite our increasingly dry climate
ANALISIS RESIKO KESEHATAN PENCEMARAN LOGAM BERAT PADA TIRAM (Saccostrea cucullata) DI PESISIR SALO PALAI, PROPINSI KALIMANTAN TIMUR
Full text linkTiram di pesisir Salo Palai, Muara Badak sangat rentan terkontaminasi oleh logam berat yang disebabkan oleh berbagai faktor lingkungan seperti terjadi secara alami, aktivitas antropogenik, perubahan iklim, dan bioakumulasi pencemaran lingkungan. Tiram (Saccostrea cucullata) dipilih untuk deteksi logam berat, dikarenakan tiram merupakan salah satu makanan laut yang dikonsumsi oleh penduduk di Salo Palai. Konsentrasi kadar Pb, Cd, dan Cu pada tiram ditentukan dengan metode destruksi asam dan AAS (Atomic Absorption Spectrophotometer). Penilaian resiko dilakukan untuk menentukan total paparan logam berat di masyarakat pesisir Salo Palai. Berdasarkan hasil analisis, konsentrasi rata-rata Pb dan Cd pada tiram lebih rendah dari Uni Eropa (2006), BSN (2009), dan China (2013), sedangkan rata –rata konsentrasi Cu rata-rata lebih tinggi dari standar Dirjen POM (1989). Kisaran nilai perkiraan asupan harian (EDI) oleh masyarakat untuk masing masing Pb (0.0000 – 0.0001) g/hari/kg, Cd (0.0000 – 0.0001) ?g/hari/ kg, dan Cu (0.0013 - 0,0213) ?g/hari/kg. Kemudian, kisaran nilai bahaya target (THQ) untuk Pb (0.0015 – 0.0249), Cd (0.0055 – 0.0913), dan Cu (0.0319 – 0.5321). Secara umum, semua nilai THQ pada tiram lebih rendah dari 1.0. Berdasarkan penelitian ini, disimpulkan bahwa tiram yang berasal dari pesisir Salo Palai, Kalimantan Timur masih layak untuk dikonsumsi, dan tidak ada efek buruk yang terjadi bagi masyarakat yang terpapar Pb, Cd, dan Cu.
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
If you build it, they will come: rapid colonization by dragonflies in a new effluent-dependent river reach
No full textBackground: Aquatic ecosystems are greatly altered by urban development, including the complete loss of natural habitat due to water diversions or channel burial. However, novel freshwater habitats also are created in cities, such as effluent-dependent streams that rely on treated wastewater for flow. It is unclear how diverse these novel ecosystems are, or how quickly aquatic species are able to colonize them. In this study, we (1) quantify odonate (Insecta, Odonata) colonization of a novel effluent-dependent river reach, (2) examine how drying events affect odonates in these novel habitats, and (3) explore whether effluent-dependent streams can support diverse odonate assemblages. Methods: We conducted monthly odonate surveys at three sites along the Santa Cruz River (Tucson, AZ, USA) between June 2019 and May 2020. One site was in a long-established effluent-dependent reach (flowing since the 1970s) that served as a reference site and two sites were in a newly-established reach that began flowing on June 24, 2019 (it was previously dry). We compared odonate species richness, assemblage composition, and colonization patterns across these reaches, and examined how these factors responded to flow cessation events in the new reach. Results: Seven odonate species were observed at the study sites in the new reach within hours of flow initiation, and species rapidly continued to arrive thereafter. Within 3 months, species richness and assemblage composition of adult odonates were indistinguishable in the new and reference reaches. However, drying events resulted in short-term and chronic reductions in species richness at one of the sites. Across all three sites, we found over 50 odonate species, which represent nearly 40% of species known from the state of Arizona. Discussion: Odonates were surprisingly diverse in the effluent-dependent Santa Cruz River and rapidly colonized a newly established reach. Richness levels remained high at study sites that did not experience drying events. These results suggest that consistent discharge of high-quality effluent into dry streambeds can be an important tool for promoting urban biodiversity. However, it remains to be seen how quickly and effectively less vagile taxa (e.g., mayflies, caddisflies) can colonize novel reaches. Effluent-dependent urban streams will always be highly managed systems, but collaboration between ecologists and urban planners could help to maximize aquatic biodiversity while still achieving goals of public safety and urban development.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
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