Graduate studentship: The University of Florida, FL, USA

Ph.D. Position in Biogeochemistry along the Freshwater-Marine Continuum

Two Ph.D. Research Assistantships at The University of Florida are available to study sources and fates of nitrogen along the fresh-water marine continuum including the role of shellfish in removing nitrogen and improving water quality. Students will be co-advised by Drs. Ashley Smyth and A.J. Reisinger and be part of UF’s Soil & Water Sciences Department in Gainesville, FL and the Tropical Research and Education Center in Homestead, FL. The students will join an interdisciplinary project with a team of graduate students’ and PI’s from Fisheries and Aquatic Sciences, Mechanical and Aerospace Engineering and Environmental Engineering Sciences. Students will work closely with the Guana Tolomato Matanzas National Estuarine Research Reserve (GTM NERR) research and education team.

Applicants from a range of backgrounds will be considered, including environmental science, biology, chemistry, or related discipline. Experience in aquatic and coastal ecosystems, and analytical chemistry is preferred. Applicants from under-served groups in STEM are strongly encouraged to apply. Students should have completed a MS degree by the project start date. Students can apply to either the Soil & Water Sciences Department or the Interdisciplinary Ecology Program in The School of Natural Resources and Environment. A competitive stipend and tuition waiver will be provided over the duration of the project. Expected start date is summer or fall 2021.

Interested candidates should contact Dr. Ashley Smyth (ashley.smyth@ufl.edu) with a CV and brief statement of research experiences and interests using Research Assistantship as the subject header before November 15, 2020. Application packets are due January 1, 2021 for fall admission. Application instructions can be found at soils.ifas.ufl.edu/academics/graduate-studies/apply or https://snre.ifas.ufl.edu/academics/graduate/how-to-apply/how-to-apply-graduate/. Note, there is no GRE requirement for Fall 2020 admission.

Postdoc (Coastal wetland research), Florida International University, Miami, FL, USA

Postdoctoral Associate in the Institute of Environment at Florida International University

Start Date: Fall 2020 or January 2021
Location: Miami, Florida, USA

A Postdoctoral Research Associate position is available in the Wetland Ecosystems Research Lab under supervision of Dr. Edward Castaneda at Florida International University. The postdoc will conduct research in Louisiana’s coastal wetlands (Delta X project) to evaluate vulnerability of coastal deltaic wetlands to sea-level rise and reduced sediment input in the Mississippi River Deltaic region. Delta-X is an interdisciplinary project including radar scientists, hydrologists, geomorphologists, and ecologists, funded by JPL-NASA (https://deltax.jpl.nasa.gov/science/team/). The candidate will also collaborate on a mangrove project in Everglades National Park to assess species-specific responses, recovery trajectories and resilience capacity of mangrove forests as a result of Hurricane Irma’s impacts across the Everglades landscape.
Candidates with a strong background in Coastal Wetland Ecology are encouraged to apply for this position. A PhD in Ecology, Oceanography and Coastal Sciences, Environmental Sciences, Earth Sciences or related field is required. Experience with management of large datasets, quantitative analysis of above- and belowground vegetation biomass and productivity data, wetland (marshes and mangroves) species identification and composition, and soil CNP biogeochemistry are required. Knowledge of statistical packages (e.g., SAS, R, JMP) and remote sensing tools (e.g., NDVI imagery, Landsat) is also preferred. The selected candidate will lead field campaigns, process and analyze data, and help with preparation of peer reviewed publications, project reports, presentations, and other communication materials. Proficiency in the operation of marine boats will be ideal.
This position will be based at the FIU Modesto A. Maidique Campus in Miami, FL, USA. The appointment is available for a one-year term with potential for renewal for a second year based on satisfactory performance and available funding.

Qualified candidates are encouraged to apply to Job Opening ID 522285 at facultycareers.fiu.edu and must submit a short letter of interest, resume, and the names and contact information for three references who are willing to provide confidential recommendations as determined by the search committee. Application materials should also be emailed as a single pdf file to Dr. Edward Castaneda (ecastane@fiu.edu). Position open until filled.

To receive full consideration, applications and required materials should be received by November 20, 2020. For an overview of research activities, visit our lab at: wetland.fiu.edu.

Postdoctoral Fellowships, Smithsonian Environmental Research Center, Edgewater, MD, USA

The Smithsonian Institution, the world’s largest museum and research complex, offers several Postdoctoral Fellowships annually to outstanding early career scientists.  The Smithsonian’s distinctive combination of field research facilities, museum archives, and expertise in ecology, biological conservation, systematics, and paleobiology provides opportunities for synthetic, big-picture insights into some of the most profound issues challenging our world today, including habitat loss, climate change, and invasive species.   

Scientists at the Smithsonian Environmental Research Center (SERC) on the Chesapeake Bay in Maryland conduct environmental research in temperate, tropical, and polar ecosystems across the globe. Recent research has highlighted the separate and interactive impacts of multiple global change factors on populations, communities, and ecosystems, including climate change, biological invasions, biodiversity loss, nutrient loading, trace element pollution, and habitat alteration.  Insights gained in these studies will be crucial to developing science-based conservation plans that allow human societies to thrive while protecting our finite natural resources.

Smithsonian Fellows receive an annual stipend of $55,000 plus health, relocation, and research allowances.  Each position is expected to run for two years, with the second year of funding contingent upon satisfactory progress.  Applicants are encouraged to coordinate with a SERC scientist prior to submitting an application for this competitively-awarded fellowship.  Applications are due November 1st.  Please contact Professional Training Coordinator, Daniel Gustafson at gustafsond@si.edu for further details or questions.

https://serc.si.edu/interns-fellows/fellowships

Fellowship Opportunities

Submit applications online:  https://solaa.si.edu/solaa/#/public

Graduate studentship: University of Arkansas, Fayetteville, AR, USA

The Magoulick Lab at the University of Arkansas is accepting applications for three Ph.D. Research Assistantships for Fall 2021. Our research efforts focus on factors affecting population and community dynamics of freshwater fish and invertebrates, especially the role of disturbance in community dynamics, impacts of invasive species in aquatic ecosystems, and conservation of aquatic ecosystems. Assistantships available are: 1) a USGS and USFWS funded project to examine environmental threshold responses of stream fish to hydrologic and thermal gradients, 2) a USGS funded project to examine effects of invasive crayfish and drought on Faxonius marchandi, an Ozark-endemic crayfish petitioned for protection under the Endangered Species Act, 3) an Arkansas State Wildlife Grant funded project to examine landscape- and local-scale habitat influences on distribution and abundance of the crayfish Faxonius eupunctus, Faxonius wagneri and Faxonius roberti in the Spring River, Strawberry River and Eleven Point River drainages. In all cases the students would have the flexibility to pursue additional research related to the funded project. These projects and related work will be carried out using a combination of comparative field studies, field and lab experiments, and modeling approaches.

Applicants should have a BS and preferably MS in fisheries, ecology, biology, or a related field; 3.2 GPA (minimum); 300 (V+Q) minimum GRE. Previous research experience with fish, crayfish and/or streams and strong quantitative skills are preferred. Applicants must be responsible, motivated, and able to work independently and in teams.

Ph.D. stipends range from $18,000 to $23,736 plus benefits and full tuition waiver with potential for additional fellowships (http://graduate-recruitment.uark.edu/funding-degree/fellowships.php). The research assistantships are available for three years and may be supplemented by a teaching assistantship in year four.

For full consideration send materials by November 15, 2020, but open until filled. Start date will be August 15, 2021.

Email 1) a letter describing your interests and career goals and how they align with the assistantship(s) for which you are applying, 2) Curriculum Vitae (including GPA and GRE scores), 3) contact info for three references, and 4) unofficial transcripts to: Dan Magoulick, danmag@uark.edu, http://danmag.wixsite.com/business-services, 479-575-5449.

Postdoc (AlgaL genomics), University of Bristol, UK

A 3 year postdoctoral research associate position is available within my MicroLab research group in the Bristol Glaciology Centre, University of Bristol. This is part of a 4-year Leverhulme Trust funded project called iDAPT: Ice Dependent Adaptations for Plant Terrestrialization.

The position is concerned with the sequencing, assembly, annotation and interrogation of ice inhabiting Streptophyte algal genomes as a means to exploring the processes of early land plant evolution and their links with the cryosphere. The role will be supervised by myself, Dr Tom Williams and Prof. Philip Donoghue, all of the University of Bristol.

The role specifics can be found using the address below:
http://www.bristol.ac.uk/jobs/find/details.html?nPostingID=74494&nPostingTargetID=197495&option=28&sort=DESC&respnr=1&ID=Q50FK026203F3VBQBV7V77V83&keywords=geography&Resultsperpage=10&lg=UK&mask=uobext

And background information on the iDAPT project and MicroLab research group through this website:
https://microlabbristol.org/research/115-2/

The application deadline is 25th October.

Please send any enquires to c.williamson@bristol.ac.uk

Graduate studentships: University of Florida, FL, USA

The Braswell Coastal Ecosystems and Watersheds Lab at the University of Florida is hiring 1-2 graduate students (Ph.D. or M.S.) to join the lab fall of 2021.

The Braswell Lab (https://braswelllab.weebly.com/) studies the connections between upland, coastal and human systems. The lab’s research program focuses on the formation, persistence and degradation of coastal ecosystems within the context of the surrounding terrestrial, marine and urban systems. We use a variety of approaches to understand these complex socio-environmental systems, including geospatial data analysis and collection of empirical field data. Linking ecological, geomorphic and demographic data, the lab’s interdisciplinary research seeks to understand coastal ecosystems within a macroscale ecology framework. The lab also works with stakeholders and managers to create tools and produce knowledge to better manage and understand coastal watersheds and ecosystems.

There will be opportunity for the student(s) to develop their research program with guidance from Dr. Braswell and other mentors. If you have a research idea, let Dr. Braswell know what you are interested in studying. Potential research topics include (but are not limited to):
1) Legacy effects of agricultural land use on water quality in coastal communities
2) Understanding sediment transport from coastal watersheds into coastal wetlands through remote sensing analysis
3) Researching the effects of human modification on geomorphic landforms in coastal wetlands
4) Exploring the connections between urbanization and ecosystem services in coastal socio-environmental systems

The ideal candidate for the position has previous research (lab, field, and/or computer-based) and data analysis experience (e.g. R, Python, ArcGIS, statistics). The candidate should be highly self-motivated, have a strong interest in being part of a collaborative team, and have a broad interest in understanding coastal systems. The Braswell lab’s work is interdisciplinary and welcomes people with backgrounds across the natural sciences (biology, geology, earth science, geography, environment science, etc.). Extension is an important component of our lab’s work, therefore interest and willingness to participate in extension projects is necessary for the successful candidate. Our lab is committed to increasing representation of women and minorities in science and encourages such candidates to apply. Although field work is often a part of the lab’s work, it is not necessary for a successful research program. Therefore, candidates of all physical abilities are encouraged to apply.

The home department of the candidate will be the Fisheries and Aquatic Sciences Program, School of Forest Resources and Conservation in UF/IFAS (http://sfrc.ufl.edu/). The position will be fully funded (2 yrs for M.S., 4 yrs for PhD) through research assistantships. Additional fellowships are available for students from diverse backgrounds (http://graduateschool.ufl.edu/prospective-students/funding/diversity-fellowships/).

To apply, please contact Dr. Anna Braswell at a.braswell@ufl.edu by November 20th, 2020 with the following attachments: 1) A one-page cover letter describing your interest in the position and your background, 2) Resume/CV, 3) Contact information for at least two professional references, and 4) Unofficial transcripts. Complete applications to the graduate program at SFRC are due January 1st, 2021.

Interspecific competition between Microcystis aeruginosa and Pseudanadaena and their production of T&O compounds

Authors

Kejia Zhang, Renjie Pan, Zhang Luo, Tuqiao Zhang, Jiajia Fan

Microcystis aeruginosa and Pseudanabaena are two common cyanobacterial species/genus and they can occur coincidently in many eutrophic lakes globally. These two cyanobacteria could produce Taste & Odor (T&O) compounds, and their production of T&O compounds might be changed when they are present coincidently. The amounts of T&O compounds and their producers may influence the effectiveness of water treatment processes. Therefore, the mutual interactions between Microcystis aeruginosa (FACHB-905, M) and Pseudanabaena sp. (FACHB-1277, P) on T&O compounds in co-cultures were evaluated in this study. Different initial cell concentrations of M and P, with ratios of M:P = 1:1, M:P = 1:2 and M:P = 2:1 were applied in the co-cultures. The growth of M was enhanced under all of the cyanobacterial cell ratios. The growth of P was enhanced under the ratio of M:P = 1:1, while it was inhibited under the ratios of M:P = 1:2 and M: P = 2:1. In addition, the growth of the two cyanobacteria and their production of β-cyclocitral and 2-methylisoborneol (2-MIB) in the filtrate of P were higher than those in the filtrate of M, which may be attributed to their associated secondary metabolites. The cell integrity and photosynthetic capacity of the two studied cyanobacteria are greatly affected by exposure to β-cyclocitral and 2-MIB. The results showed that β-cyclocitral and 2-MIB had the allelopathic effects on the two cyanobacteria species which might influence the composition of co-existing cyanobacteria and their production of T&O compounds.

Quantitative PCR based detection system for cyanobacterial geosmin/2-methylisoborneol (2-MIB) events in drinking water sources: Current status and challenges

Authors

Apramita Devia, Yi-Ting Chiua, Hsin-Ta Hsueh, Tsair-Fuh Lin

Taste and odor (T&O) are an important issue in drinking water, aquaculture, recreation and a few other associated industries, and cyanobacteria-relevant geosmin and 2-methylisoborneol (2-MIB) are the two most commonly detected T&O compounds worldwide. A rise in the cyanobacterial blooms and associated geosmin/2-MIB episodes due to anthropogenic activities as well as climate change has led to global concerns for drinking water quality. The increasing awareness for the safe drinking, aquaculture or recreational water systems has boost the demand for rapid, robust, on-site early detection and monitoring system for cyanobacterial geosmin/2-MIB events. In past years, research has indicated quantitative PCR (qPCR) as one of the promising tools for detection of geosmin/2-MIB episodes. It offers advantages of detecting the source organism even at very low concentrations, distinction of odor-producing cyanobacterial strains from non-producers and evaluation of odor producing potential of the cyanobacteria at much faster rates compared to conventional techniques.The present review aims at examining the current status of developed qPCR primers and probes in identifying and detecting the cyanobacterial blooms along with geosmin/2-MIB events. Among the more than 100 articles about cyanobacteria associated geosmin/2-MIB in drinking water systems published after 1990, limited reports (approx. 10 each for geosmin and 2-MIB) focused on qPCR detection and its application in the field. Based on the review of literature, a comprehensive open access global cyanobacterial geosmin/2-MIB events database (CyanoGM Explorer) is curated. It acts as a single platform to access updated information related to origin and geographical distribution of geosmin/2-MIB events, cyanobacterial producers, frequency, and techniques associated with the monitoring of the events. Although a total of 132 cyanobacterial strains from 21 genera and 72 cyanobacterial strains from 13 genera have been reported for geosmin and 2-MIB production, respectively, only 58 geosmin and 28 2-MIB synthesis regions have been assembled in the NCBI database. Based on the identity, geosmin sequences were found to be more diverse in the geosmin synthase conserved/primer design region, compared to 2-MIB synthesis region, hindering the design of universal primers/probes. Emerging technologies such as the bioelectronic nose, Surface Enhanced Raman Scattering (SERS), and nanopore sequencing are discussed for future applications in early on-site detection of geosmin/2-MIB and producers. In the end, the paper also highlights various challenges in applying qPCR as a universal system of monitoring and development of response system for geosmin/2-MIB episodes.

Detecting changes in statistical indicators of resilience prior to algal blooms in shallow eutrophic lakes

Authors

David Ortiz Jason Palmer Grace Wilkinson

Algal blooms in lakes and reservoirs can be considered regime shifts from a clear‐water to algae‐dominated state that often occurs abruptly. Under experimental conditions, these regime shifts have been predicted from rises in variance and autocorrelation (generic resilience indicators) of state variables monitored at a high frequency. The goal of this study was to evaluate the behavior of resilience indicators prior to a critical transition in lakes that naturally experience algal blooms. Ambient lake conditions provide several potential hurdles that could inhibit the detection of meaningful changes in resilience indicators prior to a critical transition such as stochastic nutrient loading, spatial complexity, and decreased resilience due to higher baseline nutrient concentrations. We compiled five lake‐years of high‐frequency monitoring of chlorophyll a, phycocyanin, dissolved oxygen, and pH from four hypereutrophic lakes. Despite the factors that might hinder detecting statistical indicators of changing resilience in hypereutrophic ecosystems, we found that a rise in resilience indicators did occur prior to a critical transition in three out of four possible lake‐years, with rise beginning between 5 and 33 d prior. In one lake‐year, a critical transition occurred soon after the monitoring began, preventing detection of rising variance or autocorrelation signals which are calculated using a 21‐d rolling window. These results add to the growing body of evidence that rises in resilience indicators can be detected in ecosystems prior to a regime shift if monitoring programs are properly designed to capture the dynamics; however, continued research is needed to better understand the conditions under which resilience indicators may be useful as an early warning detection tool for lake management.

Relationships of total phosphorus and chlorophyll in lakes worldwide

Authors

Roberto Quinlan Alessandro Filazzola Octavia Mahdiyan Arnab Shuvo Kevin Blagrave Carolyn Ewins Luke Moslenko Derek K. Gray Catherine M. O’Reilly Sapna Sharma

Lakes around the world are sensitive to water quality degradation and eutrophication through increases in primary production. Understanding the drivers of primary production has been a fundamental question in limnology since its early days. Here, we conducted a systematic review to develop a dataset of water chemistry and lake morphometry for 3874 lakes distributed across 47 countries around the world to answer: (1) What is the global relationship between chlorophyll a (Chl a) and total phosphorus (TP) in lakes? (2) Are there inflection points at which the TP–Chl a relationship is no longer linear? and (3) What explains the inflection points and nonlinearities in the TP–Chl a relationship? We found that a sigmoidal relationship between TP and Chl a explained 44% of the variation. We also found physical characteristics of the lake mediated the TP–Chl a relationship such as mean depth, Secchi depth, and elevation. The nonlinear segments of this relationship best described lakes located in very cold (mean annual temperature = −10°C) and hot (> 25°C) climates, which also dominated the high and low ends of TP concentrations, respectively. A positive linear TP–Chl a relationship existed at intermediate concentrations of TP (0.004–0.23 mg L⁻¹). A high degree of variability in Chl a exists between lakes at similar TP levels, highlighting the difficulty in simply decreasing nutrient inputs to manage eutrophication in lakes worldwide. Moreover, as global temperatures continue to rise, the Chl a–TP relationship in lakes located in very cold or warm temperate regions of the world may shift in response to these warmer temperatures.