The National Eutrophication Survey: lake characteristics and historical nutrient concentrations

Abstract. Historical ecological surveys serve as a baseline and provide context for contemporary research, yet many of these records are not preserved in a way that ensures their long-term usability. The National Eutrophication Survey (NES) database is currently only available as scans of the original reports (PDF files) with no embedded character information. This limits its searchability, machine readability, and the ability of current and future scientists to systematically evaluate its contents. The NES data were collected by the US Environmental Protection Agency between 1972 and 1975 as part of an effort to investigate eutrophication in freshwater lakes and reservoirs. Although several studies have manually transcribed small portions of the database in support of specific studies, there have been no systematic attempts to transcribe and preserve the database in its entirety. Here we use a combination of automated optical character recognition and manual quality assurance procedures to make these data available for analysis. The performance of the optical character recognition protocol was found to be linked to variation in the quality (clarity) of the original documents. For each of the four archival scanned reports, our quality assurance protocol found an error rate between 5.9 and 17 %. The goal of our approach was to strike a balance between efficiency and data quality by combining entry of data by hand with digital transcription technologies. The finished database contains information on the physical characteristics, hydrology, and water quality of about 800 lakes in the contiguous US (Stachelek et al., 2017, https://doi.org/10.5063/F1639MVD). Ultimately, this database could be combined with more recent studies to generate meta-analyses of water quality trends and spatial variation across the continental US.

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Establishing Climate Change Resilience in the Great Lakes in Response to Flooding

Journal of Science Policy & Governance ◽

10.38126/jspg170105 ◽

2020 ◽

Vol 17 (01) ◽

Author(s):

Gwendolyn E Gallagher ◽

Ryan K Duncombe ◽

Timothy M Steeves

Keyword(s):

Climate Change ◽

United States ◽

Water Quality ◽

Great Lakes ◽

Environmental Protection Agency ◽

High Water ◽

The United States ◽

Water Levels ◽

Storm Events ◽

Freshwater Resource

Over the past decade, both the average rainfall and the frequency of high precipitation storm events in the Great Lakes Basin have been steadily increasing as a consequence of climate change. In this same period, cities and communities along the coasts are experiencing record high water levels and severe flooding events (ECC Canada et al. 2018). When cities are unprepared for these floods, the safety of communities and the water quality of the Great Lakes are jeopardized. For example, coastal flooding increases runoff pollution and contaminates the freshwater resource that 40 million people rely on for drinking water (Lyandres and Welch 2012, Roth 2016). Since the Great Lakes are shared between two nations, the United States and Canada, the region is protected by several international treaties and national compacts, including the Great Lakes Water Quality Agreement (GLWQA) and the Great Lakes Restoration Initiative (GLRI). In order to increase climate change resiliency against flooding in the region, we recommend the United States Environmental Protection Agency (EPA) work with Environment and Climate Change Canada to relocate the GLRI under the GLWQA in order to guarantee consistent funding and protection efforts. We additionally recommend expansion of both agreements in their scope and long-term commitments to engender cooperative efforts to protect the Great Lakes against climate change.

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Derivation of an aquatic benchmark for invertebrates potentially exposed to imidacloprid

10.7287/peerj.preprints.2584v1 ◽

2016 ◽

Author(s):

Dwayne RJ Moore ◽

Colleen D Greer ◽

Melissa Whitfield-Aslund ◽

Lisa M Bowers ◽

Sean McGee ◽

...

Keyword(s):

United States ◽

Water Quality ◽

Environmental Protection Agency ◽

Species Interactions ◽

The United States ◽

Toxicity Tests ◽

Aquatic Life ◽

Invertebrate Communities ◽

Us Epa ◽

Best Fit

Water quality benchmarks are developed by many jurisdictions worldwide with the general goal of identifying concentrations that protect aquatic communities. Imidacloprid is a widely-used neonicotinoid insecticide for which benchmark values vary widely between North America and Europe. For example, the European Food Safety Authority (EFSA) and Dutch National Institute for Public Health and the Environment (RIVM) recently established chronic water quality benchmarks for imidacloprid of 0.009 and 0.0083 µg/L, respectively. In Canada and the United States (US), however, the current chronic water quality benchmarks – termed aquatic life benchmark by the United States Environmental Protection Agency (US EPA) – for freshwater biota are orders of magnitude higher, i.e., 0.23 and 1.05 µg/L, respectively. Historically, aquatic benchmarks for imidacloprid have been derived for invertebrates because they are the most sensitive aquatic receptors. To date, derivation of water quality benchmarks for imidacloprid have relied on the results of laboratory-based toxicity tests on single invertebrate species. Such tests do not account for environmental factors affecting bioavailability and toxicity or species interactions and potential for recovery. Microcosm, mesocosm and field studies are available for aquatic invertebrate communities exposed to imidacloprid. These higher tier studies are more representative of the natural environment and can be used to derive a chronic benchmark for imidacloprid. A water quality benchmark based on the results of higher tier studies is protective of freshwater invertebrate communities without the uncertainty associated with extrapolating from laboratory studies to field conditions. We used the results of higher tier studies to derive a chronic water quality benchmark for imidacloprid as follows: (1) for each taxon (family, subfamily or class depending on the study), we determined the most sensitive 21-day No Observed Effects Concentration (NOEC), (2) we fit the taxon NOECs to five distributions and determined the best-fit distribution, and (3) we determined the HC5 from the best-fit distribution. The higher tier chronic HC5 for imidacloprid is 1.01 µg/L, which is close to the current US EPA chronic aquatic life benchmark of 1.05 µg/L.

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Derivation of an aquatic benchmark for invertebrates potentially exposed to imidacloprid

10.7287/peerj.preprints.2584 ◽

2016 ◽

Author(s):

Dwayne RJ Moore ◽

Colleen D Greer ◽

Melissa Whitfield-Aslund ◽

Lisa M Bowers ◽

Sean McGee ◽

...

Keyword(s):

United States ◽

Water Quality ◽

Environmental Protection Agency ◽

Species Interactions ◽

The United States ◽

Toxicity Tests ◽

Aquatic Life ◽

Invertebrate Communities ◽

Us Epa ◽

Best Fit

Water quality benchmarks are developed by many jurisdictions worldwide with the general goal of identifying concentrations that protect aquatic communities. Imidacloprid is a widely-used neonicotinoid insecticide for which benchmark values vary widely between North America and Europe. For example, the European Food Safety Authority (EFSA) and Dutch National Institute for Public Health and the Environment (RIVM) recently established chronic water quality benchmarks for imidacloprid of 0.009 and 0.0083 µg/L, respectively. In Canada and the United States (US), however, the current chronic water quality benchmarks – termed aquatic life benchmark by the United States Environmental Protection Agency (US EPA) – for freshwater biota are orders of magnitude higher, i.e., 0.23 and 1.05 µg/L, respectively. Historically, aquatic benchmarks for imidacloprid have been derived for invertebrates because they are the most sensitive aquatic receptors. To date, derivation of water quality benchmarks for imidacloprid have relied on the results of laboratory-based toxicity tests on single invertebrate species. Such tests do not account for environmental factors affecting bioavailability and toxicity or species interactions and potential for recovery. Microcosm, mesocosm and field studies are available for aquatic invertebrate communities exposed to imidacloprid. These higher tier studies are more representative of the natural environment and can be used to derive a chronic benchmark for imidacloprid. A water quality benchmark based on the results of higher tier studies is protective of freshwater invertebrate communities without the uncertainty associated with extrapolating from laboratory studies to field conditions. We used the results of higher tier studies to derive a chronic water quality benchmark for imidacloprid as follows: (1) for each taxon (family, subfamily or class depending on the study), we determined the most sensitive 21-day No Observed Effects Concentration (NOEC), (2) we fit the taxon NOECs to five distributions and determined the best-fit distribution, and (3) we determined the HC5 from the best-fit distribution. The higher tier chronic HC5 for imidacloprid is 1.01 µg/L, which is close to the current US EPA chronic aquatic life benchmark of 1.05 µg/L.

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Water Quality Violations

Pained ◽

10.1093/oso/9780197510384.003.0006 ◽

2020 ◽

pp. 15-18

Author(s):

Michael D. Stein ◽

Sandro Galea

Keyword(s):

United States ◽

Water Quality ◽

Drinking Water ◽

High Risk ◽

Environmental Protection Agency ◽

Quality Standards ◽

The United States ◽

University Of California ◽

Contaminated Water ◽

The University

This chapter focuses on water quality violations in America. Most Americans have access to safe drinking water. However, there are pockets of American communities that are afflicted with high levels of contaminated water. In 2015, almost 10% of Americans were drinking contaminated water that violated water quality standards. The chapter then evaluates research at the University of California, Irvine, which examined water quality violations across the United States from 1982 to 2015. Researchers analyzed geographic and temporal patterns, with the goal of helping state enforcement agencies focus their attention on areas at high risk of contamination. The researchers cite decreasing population size and incomes as common obstacles faced by rural populations trying to follow water purification standards. Indeed, rural towns often rely on outside funding and low-interest government loans to support infrastructure to correct water quality violations. However, as of June 2017, over $600 million in grant funding was cut from Environmental Protection Agency drinking water programs. Such cuts, coupled with attempted environmental deregulation, threaten the public’s health.

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SELECTION TECHNIQUE FOR MULTIPLE OUTPUTS OF OPTICAL CHARACTER RECOGNITION

Eurasian Journal of Mathematical and Computer Applications ◽

10.32523/2306-6172-2020-8-2-41-51 ◽

2020 ◽

Vol 8 (2) ◽

pp. 41-51

Author(s):

I.Q. Habeeb ◽

Z.Q. Al-Zaydi ◽

H.N. Abdulkhudhur

Keyword(s):

Character Recognition ◽

Optical Character Recognition ◽

Selection Technique ◽

Multiple Outputs ◽

Optical Character

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A Structured Method for the Recognition of Complex Historical Tables

History and Computing ◽

10.3366/hac.1997.9.1-3.58 ◽

1997 ◽

Vol 9 (1-3) ◽

pp. 58-77

Author(s):

Vitaly Kliatskine ◽

Eugene Shchepin ◽

Gunnar Thorvaldsen ◽

Konstantin Zingerman ◽

Valery Lazarev

Keyword(s):

Nineteenth Century ◽

Character Recognition ◽

Optical Character Recognition ◽

Complex Structure ◽

Source Material ◽

Historical Sources ◽

Tax Assessment ◽

Optical Character ◽

Algorithmic Model ◽

Machine Readable

In principle, printed source material should be made machine-readable with systems for Optical Character Recognition, rather than being typed once more. Offthe-shelf commercial OCR programs tend, however, to be inadequate for lists with a complex layout. The tax assessment lists that assess most nineteenth century farms in Norway, constitute one example among a series of valuable sources which can only be interpreted successfully with specially designed OCR software. This paper considers the problems involved in the recognition of material with a complex table structure, outlining a new algorithmic model based on ‘linked hierarchies’. Within the scope of this model, a variety of tables and layouts can be described and recognized. The ‘linked hierarchies’ model has been implemented in the ‘CRIPT’ OCR software system, which successfully reads tables with a complex structure from several different historical sources.

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CNN-based Rain Reduction in Street View Images

London Imaging Meeting ◽

10.2352/issn.2694-118x.2020.lim-12 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 78-81

Author(s):

Simone Zini ◽

Simone Bianco ◽

Raimondo Schettini

Keyword(s):

Character Recognition ◽

Optical Character Recognition ◽

State Of The Art ◽

Weather Conditions ◽

Specific Interest ◽

Optical Character ◽

Street View ◽

In The Wild ◽

Bad Weather ◽

Detection And Recognition

Rain removal from pictures taken under bad weather conditions is a challenging task that aims to improve the overall quality and visibility of a scene. The enhanced images usually constitute the input for subsequent Computer Vision tasks such as detection and classification. In this paper, we present a Convolutional Neural Network, based on the Pix2Pix model, for rain streaks removal from images, with specific interest in evaluating the results of the processing operation with respect to the Optical Character Recognition (OCR) task. In particular, we present a way to generate a rainy version of the Street View Text Dataset (R-SVTD) for "text detection and recognition" evaluation in bad weather conditions. Experimental results on this dataset show that our model is able to outperform the state of the art in terms of two commonly used image quality metrics, and that it is capable to improve the performances of an OCR model to detect and recognise text in the wild.

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