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Communal Wastewater Treatment Plants’ Effectiveness, Management, and Quality of Groundwater: A Case Study in Indonesia
No full textThe Special Region of Yogyakarta is one of the provinces in Indonesia with a large number of communal wastewater treatment plants (CWWTPs). However, less than 40% of CWWTPS in the province are able to be operated well. This study aims to determine the effectiveness of CWWTPs concerning the quality of the surrounding groundwater. The research location was in Mlati, one of three sub-districts with the highest number of CWWTPs and highest population density in the province. Technical data were analyzed in a laboratory, including water quality of CWWTPs and groundwater quality. This study also analyzed non-technical data related to CWWTP management. These data were collected through in-depth interviews with CWWTP managers and users. The data were analyzed systematically, not only quantitatively but qualitatively. The distribution of water quality from CWWTP treatment and groundwater was mapped using inverse distance weighting (IDW). The results show that the CWWTP effluent meets quality standards for pH, temperature, COD, oil and grease, and ammonia. However, some CWWTPs fail to meet the quality standards for the TSS and E. coli parameters. Groundwater has an acidic pH, with ammonia, nitrite, and zinc parameters meeting quality standards, but oil and grease, COD, nitrate, and Pb concentrations exceed quality standards in several wells. This study indicates that the presence of CWWTPs is not correlated with the quality of groundwater due to the inefficiency of the CWWTPs, the unmet coverage area, and the conditions of sanitation facilities at the location
Genome assembly of the chemosynthetic endosymbiont of the hydrothermal vent snail Alviniconcha adamantis from the Mariana Arc
Get PDFChemosynthetic animal-microbe symbioses sustain hydrothermal vent communities in the global deep sea. In the Indo-Pacific Ocean, hydrothermal ecosystems are often dominated by gastropod species of the genus Alviniconcha, which live in association with chemosynthetic Gammaproteobacteria or Campylobacteria. While the symbiont genomes of most extant Alviniconcha species have been sequenced, no genome information is currently available for the gammaproteobacterial endosymbiont of Alviniconcha adamantis—a comparatively shallow living species that is thought to be the ancestor to all other present Alviniconcha lineages. Here, we report the first genome sequence for the symbiont of A. adamantis from the Chamorro Seamount at the Mariana Arc. Our phylogenomic analyses show that the A. adamantis symbiont is most closely related to Chromatiaceae endosymbionts of the hydrothermal vent snails Alviniconcha strummeri and Chrysomallon squamiferum, but represents a distinct bacterial species or possibly genus. Overall, the functional capacity of the A. adamantis symbiont appeared to be similar to other chemosynthetic Gammaproteobacteria, though several flagella and chemotaxis genes were detected, which are absent in other gammaproteobacterial Alviniconcha symbionts. These differences might suggest potential contrasts in symbiont transmission dynamics, host recognition, or nutrient transfer. Furthermore, an abundance of genes for ammonia transport and urea usage could indicate adaptations to the oligotrophic waters of the Mariana region, possibly via recycling of host- and environment-derived nitrogenous waste products. This genome assembly adds to the growing genomic resources for chemosynthetic bacteria from hydrothermal vents and will be valuable for future comparative genomic analyses assessing gene content evolution in relation to environment and symbiotic lifestyles
Horizontal transmission enables flexible associations with locally adapted symbiont strains in deep-sea hydrothermal vent symbioses
No full textSymbiont specificity, both at the phylotype and strain level, can have profound consequences for host ecology and evolution. However, except for insights from a few model symbiosis systems, the degree of partner fidelity and the influence of host versus environmental factors on symbiont composition are still poorly understood. Nutritional symbioses between invertebrate animals and chemosynthetic bacteria at deep-sea hydrothermal vents are examples of relatively selective associations, where hosts affiliate only with particular, environmentally acquired phylotypes of gammaproteobacterial or campylobacterial symbionts. In hydrothermal vent snails of the sister genera Alviniconcha and Ifremeria, this phylotype specificity has been shown to play a role in habitat distribution and partitioning among different holobiont species. However, it is currently unknown if fidelity goes beyond species-level associations and influences genetic structuring, connectivity, and habitat adaptation of holobiont populations. We used metagenomic analyses to assess sequence variation in hosts and symbionts and identify correlations with geographic and environmental factors. Our analyses indicate that host populations are not differentiated across an ∼800-km gradient, while symbiont populations are clearly structured between vent locations due to a combination of neutral and selective processes. Overall, these results suggest that host individuals flexibly associate with locally adapted strains of their specific symbiont phylotypes, which supports a long-standing but untested paradigm of the benefits of horizontal transmission. Symbiont strain flexibility in these snails likely enables host populations to exploit a range of habitat conditions, which might favor widespread genetic connectivity and ecological resilience unless physical dispersal barriers are present
Validation and inter-comparison of models for landslide tsunami generation
No full textThe Mapping and Modeling Subcommittee of the US National Tsunami Hazard Mitigation Program convened a workshop in January 2017 to evaluate the present state of numerical models for the simulation of tsunamis generated by submarine or subaerial landslides. A range of benchmark tests were provided to participants, with three tests emphasized: (i) a laboratory submarine solid slide in a 2D horizontal tank, (ii) a laboratory submarine granular slide in a 1D flume, and (iii) a field case based on submarine slides which occurred in Port Valdez, AK during the 1964 Alaska earthquake. Nine landslide tsunami models configured with 21 different combinations of physical options were benchmarked, including: (1) hydrostatic models with no frequency dispersion, which include the nonlinear shallow equation models traditionally used for modeling coseismic tsunamis; (2) Boussinesq or one-layer weakly dispersive models; (3) Multi-layer or non-hydrostatic (i.e., dispersive) models; and (4) Full Navier–Stokes models. Model/data comparison indicates that the inclusion of frequency dispersion in model formulations is critical to obtaining physically reasonable results for the test cases considered. Because the importance of dispersive effects is unknown a priori for any given simulated event, the central recommendation from this work is that a model with at minimum a leading-order representation of frequency dispersion effects be used whenever possible for landslide tsunami simulations
Development of major element proxies for magmatic H2O content in oceanic basalts
No full textAnalysis of H2O concentrations in quenched glass has enabled significant improvements in our understanding of its role in mantle melting, magma differentiation, eruption dynamics, and the origin of mantle heterogeneity. Direct measurements of dissolved H2O in glass, however, are not always possible, and we lack robust methods of constraining magmatic H2O contents in aphyric, bulk rock samples that lack glass. Here, we present a major element hygrometer for mid-ocean ridge (MOR) and back-arc basin (BAB) basalt magmas based on the sensitivity of phenocryst phase assemblages to magmatic H2O contents, which translate into resolvable differences in liquid lines of descent (LLDs) as a function of magmatic H2O concentrations. Existing hygrometers lack sufficient resolution to be useful at the low H2O concentrations typical of MOR and BAB basalts (\u3c1.0 wt%). We develop the major element proxy, Al2O3/FeO*(7.0) (fractionation-corrected to 7 wt% MgO), for determining magmatic H2O contents using cogenetic suites of oceanic basalts with well-defined LLDs and well-constrained H2O contents. H2O(7.0) positively correlates with Al2O3/FeO*(7.0) in the mid-ocean ridge basalt dataset, and this relationship is maintained in back-arc basin basalts with a broader range of water contents (up to 2.0 wt%). The main petrological control over this covariation is the role of H2O in suppressing plagioclase crystallization, while crystallization pressure and magmatic oxygen fugacity play lesser roles. Herein, we present an empirical model that uses Al2O3/FeO*(7.0) to estimate the magmatic water content in plagioclase-saturated oceanic basaltic magmas: H2O(7.0) = 1.109Al2O3/FeO∗(7.0) − 1.111. This model enables the estimation of magmatic H2O content using whole-rock major element data, which can be readily determined for aphyric or crystalline lavas that lack quenched glassy rinds, melt inclusions, or appropriate phenocryst assemblages
Managed Nitrogen Load Decrease Reduces Chlorophyll and Hypoxia in Warming Temperate Urban Estuary
Get PDFMany urban estuaries worldwide suffer from excess phytoplankton and hypoxia (low oxygen) due to high nutrient loads. A common water quality management strategy is to require wastewater treatment facility upgrades. This case study examines Narragansett Bay, a warming temperate mid-latitude urban estuary with seasonal periodic hypoxia, during June through September from 2005 to 2019. Within this period, numerous facilities were upgraded to nitrogen removal over several years. The response of the bay is more consistent with “textbook” expectations for reduced chlorophyll and hypoxia than what was seen in many other systems—despite its complex coastline geometry, numerous river inputs, and widely-distributed treatment facilities. River flow drives inter-annual variability with increased load, density stratification, chlorophyll, and hypoxia in wet years. Mean 2013-2019 bay-wide total nitrogen load was 34% less than the 2005-2012 mean, a reduction of about 106 kg yr-1, comparable to the range of flow-driven inter-annual variations. Chlorophyll Index and Hypoxia Index event-based metrics applied to high-frequency time series observations at eight sites quantify exceedances of severe and moderate thresholds. Relatively steady 33% and 16% Chlorophyll Index declines, for severe and moderate thresholds, occurred from about 2007 to 2019. The Hypoxia Index declined markedly by 2009 and 2014 for severe and moderate thresholds, respectively, and remained at or near zero from 2014 to 2019. The load reduction explains chlorophyll and hypoxia declines better than physical processes including river flow, stratification, tidal variations, winds, sea level differences, and temperatures. River flow about 55% higher than the 2005-2019 mean would increase non-treatment facility loads by an amount comparable to the managed load decrease, so future wet summers could partially reverse the improvements. Long-term trends include warming of about 0.5°C decade-1, which reduces oxygen saturation by 0.1 mg l-1 decade-1. This rate is likely a lower bound for temperature-driven oxygen decreases, because warming can also accelerate phytoplankton growth and bacterial consumption. Without warming, the managed load decrease would have curtailed hypoxia more effectively. Climate trends should be at least as important to future eutrophication as the managed load decline because, in addition to warming influences, long-term increases in river flow would increase load and stratification
New Constraints on Assemblage-Driven Variation in the Relationship Amongst Diatom-Bound, Biomass, and Nitrate Nitrogen Isotope Values
No full textTracking variations in the surface ocean supply and demand of nitrate, a key marine nutrient, can help constrain the contribution of biological production in driving past climate shifts. The nitrogen isotopic composition (as δ15N) of organic matter in marine sediments is a proxy for surface ocean nitrate supply and demand over time, but it may be subject to alteration during sinking and burial. The isotopic composition of nitrogen occluded in the opal shells, or frustules, of diatoms (δ15NDB) is protected and is, therefore, a potentially more robust tracer of nitrate use in the past. Here, we show that δ15NDB in Southern Ocean growout cultures of natural communities does not depend on species composition. We found that the εDB (= biomass δ15N–δ15NDB) of the community growouts was −4.8 ± 0.8‰, more than 10‰ different from previous monospecific growouts, but statistically indistinguishable from previous Southern Ocean and North Pacific surface ocean observations. The two community growouts, seeded with populations from ∼66° to ∼61°S, had distinct community compositions, but indistinguishable εDB, suggesting that species composition does not primarily set δ15NDB values, at least in Antarctic and Polar Frontal Zones of the Southern Ocean. Our results demonstrate that under nitrate-replete conditions, δ15NDB values of frustules sinking from the surface ocean robustly track surface ocean nitrate δ15N values, and therefore nitrate supply and demand
Correction to: Post-Hurricane Sandy Benthic Habitat Mapping at Fire Island National Seashore, New York, USA, Utilizing the Coastal and Marine Ecological Classification Standard (CMECS) (Estuaries and Coasts, (2022), 45, 4, (1070-1094), 10.1007/s12237-022-01047-z)
Get PDFThe article Post-Hurricane Sandy Benthic Habitat Mapping at Fire Island National Seashore, New York, USA, Utilizing the Coastal and Marine Ecological Classification Standard (CMECS), written by LaFrance Bartley et al., was originally published electronically on the publisher’s internet portal on March 19, 2022, without Open Access. With the authors’ decision to opt for Open Choice, the article is forthwith distributed under a Creative Commons Attribution 4.0 International License
The interactive effects of temperature and nutrients on a spring phytoplankton community
Get PDFA complex interplay of environmental variables impacts phytoplankton community composition and physiology. Temperature and nutrient availability are two principal factors driving phytoplankton growth and composition, but are often investigated independently and on individual species in the laboratory. To assess the individual and interactive effects of temperature and nutrient concentration on phytoplankton community composition and physiology, we altered both the thermal and nutrient conditions of a cold-adapted spring phytoplankton community in Narragansett Bay, Rhode Island, when surface temperature was 2.6°C and chlorophyll \u3e 9 μg L−1. Water was incubated in triplicate at −0.5°C, 2.6°C, and 6°C for 10 d. At each temperature, treatments included both nutrient amendments (N, P, Si addition) and controls (no macronutrients added). The interactive effects of temperature and resource availability altered phytoplankton growth and community structure. Nutrient amendments resulted in species sorting and communities dominated by larger species. Under replete nutrients, warming tripled phytoplankton growth rates, but under in situ nutrient conditions, increased temperature acted antagonistically, reducing growth rates by as much as 33%, suggesting communities became nutrient limited. The temperature–nutrient interplay shifted the relative proportions of each species within the phytoplankton community, resulting in more silica rich cells at decreasing temperatures, irrespective of nutrients, and C : N that varied based on resource availability, with nutrient limitation inducing a 47% increase in C : N at increasing temperatures. Our results illustrate how the temperature–nutrient interplay can alter phytoplankton community dynamics, with changes in temperature amplifying or exacerbating the nutrient effect with implications for higher trophic levels and carbon flux
On Juneteenth: The Essential Story of “Freedom Day” and Its Importance to American History
No full textOn January 1, 1863, President Abraham Lincoln issued the Emancipation Proclamation that declared more than three million enslaved people living in the Confederate States to be free. It was not until June 19, 1865, however, that Union Army General Gordon Granger arrived in Texas with the news. Since then Juneteenth has been celebrated on June 19 in Texas and many other states to commemorate the emancipation of enslaved people, but it was not until 2021 that Congress recognized Juneteenth as a federal holiday. In this talk, Pulitzer Prize-winning historian Annette Gordon-Reed will discuss her recent book, On Juneteenth, a blend of memoir and history that explores the violence and oppression that preceded and followed this celebration, what it means to us now, and how it relates to our larger fight for equality.
Annette Gordon-Reed is a Professor of History in the Faculty of Arts and Sciences at Harvard University, the Carl M. Loeb University Professor at Harvard Law School, and the award-winning author of six books. Her latest book, On Juneteenth, sets out to capture the integral importance of the holiday to American history.
Professor Gordon-Reed is also the author of The Hemingses of Monticello: An American Family, which won the Pulitzer Prize in history and the National Book Award for nonfiction—along with fourteen other awards. It explores the inconsistencies of Jefferson’s stance on slavery and his relationship with enslaved woman Sally Hemings, and has been called “the best study of a slave family ever written” by noted Jefferson scholar Joseph Ellis. Her other books include Thomas Jefferson and Sally Hemings: An American Controversy—a rich examination of scholarly writing on the relationships between Jefferson and Hemings, which exposes the possibility that scholars were misguided by their own biases and may even have contorted evidence to preserve their preexisting opinions of Jefferson. Her other book, “Most Blessed of the Patriarchs”: Thomas Jefferson and the Empire of the Imagination, presents a provocative character study of Jefferson that challenges much of the scholarly status quo on his portrayal throughout history. Her upcoming title, A Jefferson Reader on Race, is set to be published in 2022.
Professor Gordon-Reed’s honors include the National Humanities Medal (awarded by President Barack Obama), a Guggenheim Fellowship, and a MacArthur Fellowship. She was also elected a Fellow of the American Academy of Arts and Sciences, and is a member of the Academy’s Commission on the Humanities and Social Sciences. In 2019, she was elected a Member of the American Philosophical Society.
Click here for photos of the 2021-22 Spring Humanities Festival