scholarly journals Quantifying Marine Plastic Debris in a Beach Environment Using Spectral Analysis

2021 ◽  
Vol 13 (22) ◽  
pp. 4548
Author(s):  
Jenna A. Guffogg ◽  
Samantha M. Blades ◽  
Mariela Soto-Berelov ◽  
Chris J. Bellman ◽  
Andrew K. Skidmore ◽  
...  
Keyword(s):  
Marine Environment ◽  
Spectral Feature ◽  
Detection Methods ◽  
Surface Layers ◽  
Plastic Debris ◽  
Surface Cover ◽  
Sandy Substrate ◽  
Beach Litter ◽  
The Impact ◽  
Marine Plastic Debris

Marine plastic debris (MPD) is a globally relevant environmental challenge, with an estimated 8 million tons of synthetic debris entering the marine environment each year. Plastic has been found in all parts of the marine environment, including the surface layers of the ocean, within the water column, in coastal waters, on the benthic layer and on beaches. While research on detecting MPD using remote sensing is increasing, most of it focuses on detecting floating debris in open waters, rather than detecting MPD on beaches. However, beaches present challenges that are unique from other parts of the marine environment. In order to better understand the spectral properties of beached MPD, we present the SWIR reflectance of weathered MPD and virgin plastics over a sandy substrate. We conducted spectral feature analysis on the different plastic groups to better understand the impact that polymers have on our ability to detect synthetic debris at sub-pixel surface covers that occur on beaches. Our results show that the minimum surface cover required to detect MPD on a sandy surface varies between 2–8% for different polymer types. Furthermore, plastic composition affects the magnitude of spectral absorption. This suggests that variation in both surface cover and polymer type will inform the efficacy of beach litter detection methods.

scholarly journals Interaction of Plastics with Marine Species

2020 ◽  
Vol 20 (8) ◽  
pp. 647-658 ◽  
Author(s):  
Rafet Cagri Ozturk ◽  
Ilhan Altinok
Keyword(s):  
Marine Environment ◽  
Current Knowledge ◽  
Sea Turtles ◽  
Marine Species ◽  
Detection Methods ◽  
Sea Stars ◽  
Marine Animals ◽  
Filter Feeder ◽  
Wide Range ◽  
The Impact

The plastic litter in the seas and oceans has become one of the major threats for environment and a wide range of marine species worldwide. Microplastics are the most common litters in the marine environment corresponding to 60-80% of the total litter in the world’s seas. The risk factor of plastics is inversely associated with the size of the plastic. In the present study, we reviewed the state of knowledge regarding the impact of plastic pollution on marine environment and marine species, assessing the ingestion incidences, elimination of plastics, interactions of plastics with other pollutants, and effects on photosynthesis. Records of marine species ingesting plastic have increased and begin to attract considerable attention. Metadata generated from the review of related papers in the present study was used to evaluate the current knowledge on the plastic ingestion by different marine species. The retrieved data from reviewed articles revealed that the ingestion of plastic by marine animals have been documented in more than 560 species including fish, crustaceans, mammals, sea turtles, bivalves, gastropods even in sea stars and limpets. The size of ingested plastics varied from species to species generally depending on the feeding behavior. Microplastics showed the highest number of bibliographic citations in the plastic ingestion studies. They are mostly ingested by planktivorous and filter feeder species. Meso, macro, and occasionally megaplastics are reported in marine mammals and sea turtles since they often confuse plastic for their prey. The sensitivity and size of the detected plastics may vary based on the analytical plastic detection methods.

The efficiency of application of virtual cross-sections method and hypotheses MELS in problems of wave signal propagation in elastic waveguides with rough surfaces

2016 ◽  
pp. 3564-3575 ◽  
Author(s):  
Ara Sergey Avetisyan
Keyword(s):  
Half Space ◽  
Cross Sections ◽  
Classical Method ◽  
Signal Propagation ◽  
Elastic Half Space ◽  
Layered Systems ◽  
Surface Layers ◽  
Inhomogeneous Surface ◽  
Wave Signal ◽  
The Impact

The efficiency of virtual cross sections method and MELS (Magneto Elastic Layered Systems) hypotheses application is shown on model problem about distribution of wave field in thin surface layers of waveguide when plane wave signal is propagating in it. The impact of surface non-smoothness on characteristics of propagation of high-frequency horizontally polarized wave signal in isotropic elastic half-space is studied. It is shown that the non-smoothness leads to strong distortion of the wave signal over the waveguide thickness and along wave signal propagation direction as well.  Numerical comparative analysis of change in amplitude and phase characteristics of obtained wave fields against roughness of weakly inhomogeneous surface of homogeneous elastic half-space surface is done by classical method and by proposed approach for different kind of non-smoothness.

Geosynthetic materials as a source of pollution of the marine environment by plastic debris

2018 ◽  
Vol 53 (3) ◽  
pp. 15 ◽  
Author(s):  
Elena E. Esiukova ◽  
Boris V. Chubarenko ◽  
E. M. Burnashov ◽  
Keyword(s):  
Marine Environment ◽  
Plastic Debris ◽  
Source Of Pollution

The impact of urban effluents on the coastal marine environment of Mediterranean islands

1995 ◽  
Vol 32 (9-10) ◽  
pp. 85-94 ◽  
Author(s):  
Michael O. Angelidis
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Marine Environment ◽  
Suspended Particle ◽  
Pollution Source ◽  
Mediterranean Islands ◽  
Coastal Marine Environment ◽  
Coastal Marine ◽  
The Impact ◽  
The City

The impact of the urban effluents of Mytilene (Lesvos island, Greece) on the receiving coastal marine environment, was evaluated by studying the quality of the city effluents (BOD5, COD, SS, heavy metals) and the marine sediments (grain size, organic matter, heavy metals). It was found that the urban effluents of Mytilene contain high organic matter and suspended particle load because of septage discharge into the sewerage network. Furthermore, although the city does not host important industrial activity, its effluents contain appreciable metal load, which is mainly associated with the particulate phase. The city effluents are discharged into the coastal marine environment and their colloidal and particulate matter after flocculation settles to the bottom, where is incorporated into the sediments. Over the years, the accumulation of organic matter and metals into the harbour mud has created a non-point pollution source in the relatively non-polluted coastal marine environment of the island. Copper and Zn were the metals which presented the higher enrichment in the sediments of the inner harbour of Mytilene.

scholarly journals A Survey of Marine Coastal Litters around Zhoushan Island, China and Their Impacts

2021 ◽  
Vol 9 (2) ◽  
pp. 183
Author(s):  
Xuehua Ma ◽  
Yi Zhou ◽  
Luyi Yang ◽  
Jianfeng Tong
Keyword(s):  
Rapid Development ◽  
Univariate Analysis ◽  
Local Environment ◽  
Marine Litter ◽  
Social Ecological ◽  
The Social ◽  
Significant Difference ◽  
Valuable Method ◽  
Beach Litter ◽  
The Impact

Rapid development of the economy increased marine litter around Zhoushan Island. Social-ecological scenario studies can help to develop strategies to adapt to such change. To investigate the present situation of marine litter pollution, a stratified random sampling (StRS) method was applied to survey the distribution of marine coastal litters around Zhoushan Island. A univariate analysis of variance was conducted to access the amount of litter in different landforms that include mudflats, artificial and rocky beaches. In addition, two questionnaires were designed for local fishermen and tourists to provide social scenarios. The results showed that the distribution of litter in different landforms was significantly different, while the distribution of litter in different sampling points had no significant difference. The StRS survey showed to be a valuable method for giving a relative overview of beach litter around Zhoushan Island with less effort in a future survey. The questionnaire feedbacks helped to understand the source of marine litter and showed the impact on the local environment and economy. Based on the social-ecological scenarios, governance recommendations were provided in this paper.

scholarly journals A Systematic Review of Landsat Data for Change Detection Applications: 50 Years of Monitoring the Earth

2021 ◽  
Vol 13 (15) ◽  
pp. 2869
Author(s):  
MohammadAli Hemati ◽  
Mahdi Hasanlou ◽  
Masoud Mahdianpari ◽  
Fariba Mohammadimanesh
Keyword(s):  
Time Series ◽  
Change Detection ◽  
Policy Development ◽  
Atmospheric Correction ◽  
Open Data ◽  
Detection Methods ◽  
Landsat 8 ◽  
Landsat Images ◽  
Detection Analysis ◽  
The Impact

With uninterrupted space-based data collection since 1972, Landsat plays a key role in systematic monitoring of the Earth’s surface, enabled by an extensive and free, radiometrically consistent, global archive of imagery. Governments and international organizations rely on Landsat time series for monitoring and deriving a systematic understanding of the dynamics of the Earth’s surface at a spatial scale relevant to management, scientific inquiry, and policy development. In this study, we identify trends in Landsat-informed change detection studies by surveying 50 years of published applications, processing, and change detection methods. Specifically, a representative database was created resulting in 490 relevant journal articles derived from the Web of Science and Scopus. From these articles, we provide a review of recent developments, opportunities, and trends in Landsat change detection studies. The impact of the Landsat free and open data policy in 2008 is evident in the literature as a turning point in the number and nature of change detection studies. Based upon the search terms used and articles included, average number of Landsat images used in studies increased from 10 images before 2008 to 100,000 images in 2020. The 2008 opening of the Landsat archive resulted in a marked increase in the number of images used per study, typically providing the basis for the other trends in evidence. These key trends include an increase in automated processing, use of analysis-ready data (especially those with atmospheric correction), and use of cloud computing platforms, all over increasing large areas. The nature of change methods has evolved from representative bi-temporal pairs to time series of images capturing dynamics and trends, capable of revealing both gradual and abrupt changes. The result also revealed a greater use of nonparametric classifiers for Landsat change detection analysis. Landsat-9, to be launched in September 2021, in combination with the continued operation of Landsat-8 and integration with Sentinel-2, enhances opportunities for improved monitoring of change over increasingly larger areas with greater intra- and interannual frequency.

scholarly journals Screening for Melanoma and Other Skin Cancer Shows a Higher Early Melanoma Incidence: Social Educational Program “Life Fear-Free”

2021 ◽  
Vol 8 (1) ◽  
pp. 54-68
Author(s):  
Lev Demidov ◽  
Igor Samoylenko ◽  
Nina Vand ◽  
Igor Utyashev ◽  
Irina Shubina ◽  
...  
Keyword(s):  
Skin Cancer ◽  
Screening Program ◽  
Excisional Biopsy ◽  
Skin Lesions ◽  
Detection Methods ◽  
Non Melanoma Skin Cancer ◽  
The Social ◽  
Educational Campaign ◽  
Skin Cancer Detection ◽  
The Impact

Background: The screening program Life Fear-Free (LFF) aimed at early diagnosis of cutaneous melanoma (CM) was introduced in Samara, Chelyabinsk, Yekaterinburg, and Krasnodar (Russia) in 2019. Objectives: To analyze the impact of the program on early CM and non-melanoma skin cancer (NMSC) detection. Methods: According to the social educational campaign, people were informed about CM risk factors and symptoms and were invited for skin examination. The program planned to involve 3200 participants in total. Participants with suspicious lesions were invited for excisional biopsy. Results: 3143 participants, including 75.4% women, were examined for skin lesions. The average age of the participants was 43.7 years. Mostly skin phototypes II and III were registered (48.2% and 41.0%, respectively); 3 patients had CM, 15 had basal cell carcinoma, and 1 had Bowen’s disease, which were confirmed histologically. All detected melanomas had Breslow’s thickness of 1 mm. Conclusion: The participants showed high interest in early skin cancer detection programs. The incidence rate of CM and NMSCs among the program participants was higher than in general public. The early disease grade was proven for the detected CMs and NMSCs. The study has shown that it is important to continue such programs.

scholarly journals Hydrothermal carbonization (HTC) of marine plastic debris

Fuel ◽  
2019 ◽  
Vol 257 ◽  
pp. 116033 ◽  
Author(s):  
María E. Iñiguez ◽  
Juan A. Conesa ◽  
Andrés Fullana
Keyword(s):  
Hydrothermal Carbonization ◽  
Plastic Debris ◽  
Marine Plastic Debris

scholarly journals Understanding the Fragmentation Pattern of Marine Plastic Debris

2016 ◽  
Vol 50 (11) ◽  
pp. 5668-5675 ◽  
Author(s):  
Alexandra ter Halle ◽  
Lucie Ladirat ◽  
Xavier Gendre ◽  
Dominique Goudouneche ◽  
Claire Pusineri ◽  
...  
Keyword(s):  
Fragmentation Pattern ◽  
Plastic Debris ◽  
Marine Plastic Debris

A noise reduction method for semi-supervised community detection based on harmonic function

2018 ◽  
Vol 32 (14) ◽  
pp. 1850166 ◽  
Author(s):  
Lilin Fan ◽  
Kaiyuan Song ◽  
Dong Liu
Keyword(s):  
Harmonic Function ◽  
Prior Knowledge ◽  
Community Detection ◽  
Detection Methods ◽  
Detection Process ◽  
Knowledge Based ◽  
Detection Approach ◽  
Series Of Experiments ◽  
Novel Strategy ◽  
The Impact

Semi-supervised community detection is an important research topic in the field of complex network, which incorporates prior knowledge and topology to guide the community detection process. However, most of the previous work ignores the impact of the noise from prior knowledge during the community detection process. This paper proposes a novel strategy to identify and remove the noise from prior knowledge based on harmonic function, so as to make use of prior knowledge more efficiently. Finally, this strategy is applied to three state-of-the-art semi-supervised community detection methods. A series of experiments on both real and artificial networks demonstrate that the accuracy of semi-supervised community detection approach can be further improved.

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