scholarly journals eDNA reveals estuarine benthic community response to nutrient enrichment – evidence from an in-situ experiment

2021 ◽  
Vol 4 ◽  
Author(s):  
Dana Clark ◽  
Conrad Pilditch ◽  
Joanne Ellis ◽  
Angel Borja ◽  
Javier Atalah ◽  
...  
Keyword(s):  
Nutrient Enrichment ◽  
Nutrient Loading ◽  
Benthic Communities ◽  
Health Assessment ◽  
Environmental Dna ◽  
Community Response ◽  
Assessment Tools ◽  
In Situ Experiment ◽  
Early Signs ◽  
Monitoring Tools

Nutrient loading is a major threat to estuaries and coastal environments worldwide, therefore, it is critical that we have good monitoring tools to detect early signs of degradation in these ecologically important and vulnerable ecosystems. We carried out a seven-month manipulative experiment in two estuaries to assess the effects of nutrient loading on benthic communities. Environmental DNA metabarcoding was used to examine the response of eukaryotic (18S rRNA), diatom (rbcL), and bacterial (16S rRNA) communities to two levels of nutrient enrichment (150 and 600 g N m-2). Multivariate analyses demonstrated consistent changes in eukaryotic, diatom, and bacterial communities in response to enrichment, despite differing environmental conditions between sites (Fig. 1). These patterns aligned with changes in macrofaunal communities identified using traditional morphological techniques, confirming concordance between disturbance indicators detected by eDNA and current monitoring approaches. Clear shifts in eukaryotic and bacterial indicator taxa were seen in response to nutrient loading while changes in diatom communities were more subtle. Community changes were discernable between nutrient levels, suggesting that estuary health assessment tools could be developed to detect early signs of degradation. Existing eDNA-based biotic indices (microgAMBI and mtMBI) were able to detect these community shifts, suggesting transferability of these indices to other regions and systems. This work represents a first step towards the development of molecular-based estuary monitoring tools, which could provide a more holistic and sensitive approach to ecosystem health assessment with faster turn-around times and lower costs.

scholarly journals Restored freshwater flow and estuarine benthic communities in the northern Gulf of Mexico: research trends and future needs

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8587
Author(s):  
Jillian C. Tupitza ◽  
Cassandra N. Glaspie
Keyword(s):  
Mississippi River ◽  
Large Scale ◽  
Aquatic Vegetation ◽  
Nutrient Loading ◽  
Benthic Communities ◽  
Geographic Region ◽  
Community Response ◽  
The Body ◽  
Future Research ◽  
Freshwater Flow

Restoring river connectivity to rebuild and sustain land is a promising restoration strategy in coastal areas experiencing rapid land loss, such as the Mississippi river delta. Results of these large-scale hydrologic changes are preliminary, and there exists limited empirical evidence regarding how benthic communities will respond, specifically in Barataria Bay and Breton Sound in southeast Louisiana. In this review, the body of existing research in this geographic region pertaining to the drivers of benthic community response that are related to restored freshwater flow and sediment deposition is examined. Overall trends include (1) potential displacement of some species down-estuary due to reduced salinities; (2) temporary lower diversity in areas closest to the inflow; (3) increased benthic production along the marsh edge, and in tidal bayous, as a result of nutrient loading; (4) more habitat coverage in the form of submerged aquatic vegetation; and (5) reduced predation pressure from large and/or salinity-restricted predators. These trends highlight opportunities for future research that should be conducted before large-scale hydrologic changes take place.

scholarly journals Formal Verification of Health Assessment Tools: a Case Study

2016 ◽  
Vol 324 ◽  
pp. 31-50 ◽  
Author(s):  
Jonas Santos Bezerra ◽  
Andrei Costa ◽  
Leila Ribeiro ◽  
Érika Cota
Keyword(s):  
Formal Verification ◽  
Health Assessment ◽  
Assessment Tools

Health and Fall Risk Monitoring Within Common Assessments

2021 ◽  
pp. 182-199
Author(s):  
Rafael Nogueira Rodrigues ◽  
Adriana Caldo ◽  
Fernanda M. Silva ◽  
Cidalina Conceição Ferreira Abreu ◽  
Guilherme Eustaquio Furtado ◽  
...  
Keyword(s):  
Global Health ◽  
Fall Risk ◽  
Health Assessment ◽  
Assessment Tools ◽  
Specific Intervention ◽  
Common Assessments ◽  
Risk Monitoring ◽  
Fitness Assessment ◽  
Assessment And Monitoring ◽  
Specific Assessment

This chapter presents an exploratory review on the evaluation, assessment, and monitoring in health and fall risk by common and the most used assessment tools. The main discussion of this chapter of evaluation in health and fall risk is divided into six categories—global health assessment, specific physical (and fitness) assessment, cognitive and psychological assessment, pharmacological assessment, fall risk specific assessment, and some complementary assessment—which show information and how to access. Whereas health evaluative experiences and practices are essential to drive a better and specific intervention, revealing its importance and necessity was also highlighted.

Algae community response to climate change and nutrient loading recorded by sedimentary phytoplankton pigments in the Changtan Reservoir, China

2019 ◽  
Vol 571 ◽  
pp. 311-321 ◽  
Author(s):  
Shouliang Huo ◽  
Hanxiao Zhang ◽  
Chunzi Ma ◽  
Beidou Xi ◽  
Jingtian Zhang ◽  
...  
Keyword(s):  
Climate Change ◽  
Nutrient Loading ◽  
Community Response ◽  
Phytoplankton Pigments

Health Status Screening in Elderly Patients — Is this the Way Forward?

2012 ◽  
Vol 08 (01) ◽  
pp. 63
Author(s):  
Joanna Kazmierska ◽  
Keyword(s):  
Health Status ◽  
Health Assessment ◽  
European Population ◽  
Assessment Tools ◽  
Screening Tools ◽  
Screening Methods ◽  
Age Group ◽  
Cognitive Domains ◽  
Standard Assessment ◽  
Pre Treatment

The rapid ageing of the European population poses a challenge for healthcare systems. The incidence of cancers will rise as the number of adults aged 65 years and older increases. Moreover, the health status of individuals in this age group is diverse, and thus requires modern oncology to apply an individualised approach to treatment. There is a clear need to develop and validate health assessment tools enabling the identification of specific geriatric issues which might be overlooked by standard assessment methods. The Comprehensive Geriatric Assessment (CGA) is the ‘gold standard’ for geronto-oncology assessment. However, the complexity of this test has stimulated a search for pre-screening methods able to identify individuals with the potential to gain most from full pre-treatment CGA. Such tools consist of specific tests to evaluate health status in the important functional, psychological, social and cognitive domains. The choice of which tests are best to use within the various screening tools is still a subject of debate. This paper presents a review of the most commonly used tests within various health status domains as well as of the most valuable screening tools.

scholarly journals Functional Responses of Salt Marsh Microbial Communities to Long-Term Nutrient Enrichment

2016 ◽  
Vol 82 (9) ◽  
pp. 2862-2871 ◽  
Author(s):  
Christopher J. Graves ◽  
Elizabeth J. Makrides ◽  
Victor T. Schmidt ◽  
Anne E. Giblin ◽  
Zoe G. Cardon ◽  
...  
Keyword(s):  
Salt Marsh ◽  
Microbial Communities ◽  
Relative Abundance ◽  
Nutrient Enrichment ◽  
Nutrient Loading ◽  
Whole Genome ◽  
Sewage Effluent ◽  
Fine Scale ◽  
Functional Responses

ABSTRACTEnvironmental nutrient enrichment from human agricultural and waste runoff could cause changes to microbial communities that allow them to capitalize on newly available resources. Currently, the response of microbial communities to nutrient enrichment remains poorly understood, and, while some studies have shown no clear changes in community composition in response to heavy nutrient loading, others targeting specific genes have demonstrated clear impacts. In this study, we compared functional metagenomic profiles from sediment samples taken along two salt marsh creeks, one of which was exposed for more than 40 years to treated sewage effluent at its head. We identified strong and consistent increases in the relative abundance of microbial genes related to each of the biochemical steps in the denitrification pathway at enriched sites. Despite fine-scale local increases in the abundance of denitrification-related genes, the overall community structures based on broadly defined functional groups and taxonomic annotations were similar and varied with other environmental factors, such as salinity, which were common to both creeks. Homology-based taxonomic assignments of nitrous oxide reductase sequences in our data show that increases are spread over a broad taxonomic range, thus limiting detection from taxonomic data alone. Together, these results illustrate a functionally targeted yet taxonomically broad response of microbial communities to anthropogenic nutrient loading, indicating some resolution to the apparently conflicting results of existing studies on the impacts of nutrient loading in sediment communities.IMPORTANCEIn this study, we used environmental metagenomics to assess the response of microbial communities in estuarine sediments to long-term, nutrient-rich sewage effluent exposure. Unlike previous studies, which have mainly characterized communities based on taxonomic data or primer-based amplification of specific target genes, our whole-genome metagenomics approach allowed an unbiased assessment of the abundance of denitrification-related genes across the entire community. We identified strong and consistent increases in the relative abundance of gene sequences related to denitrification pathways across a broad phylogenetic range at sites exposed to long-term nutrient addition. While further work is needed to determine the consequences of these community responses in regulating environmental nutrient cycles, the increased abundance of bacteria harboring denitrification genes suggests that such processes may be locally upregulated. In addition, our results illustrate how whole-genome metagenomics combined with targeted hypothesis testing can reveal fine-scale responses of microbial communities to environmental disturbance.

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