Description: Marine researchers continue to create large quantities of benthic images e.g., using AUVs (Autonomous Underwater Vehicles). In order to quantify the size of sessile objects in the images, a pixel-to-centimeter ratio is required for each image, often indirectly provided through a geometric laser point (LP) pattern, projected onto the seafloor. Manual annotation of these LPs in all images is too time-consuming and thus infeasible for nowadays data volumes. Because of the technical evolution of camera rigs, the LP's geometrical layout and color features vary for different expeditions and projects. This makes the application of one algorithm, tuned to a strictly defined LP pattern, also ineffective. Here we present the web-tool DELPHI, that efficiently learns the LP layout for one image transect/collection from just a small number of hand labeled LPs and applies this layout model to the rest of the data. The efficiency in adapting to new data allows to compute the LPs and the pixel-to-centimeter ratio fully automatic and with high accuracy. DELPHI is applied to two real-world examples and shows clear improvements regarding reduction of tuning effort for new LP patterns as well as increasing detection performance.

Description: This book describes how manmade litter, primarily plastic, has spread into the remotest parts of the oceans and covers all aspects of this pollution problem from the impacts on wildlife and human health to socio-economic and political issues. Marine litter is a prime threat to marine wildlife, habitats and food webs worldwide. The book illustrates how advanced technologies from deep-sea research, microbiology and mathematic modelling as well as classic beach litter counts by volunteers contributed to the broad awareness of marine litter as a problem of global significance. The authors summarise more than five decades of marine litter research, which receives growing attention after the recent discovery of great oceanic garbage patches and the ubiquity of microscopic plastic particles in marine organisms and habitats. In 16 chapters, authors from all over the world have created a universal view on the diverse field of marine litter pollution, the biological impacts, dedicated research activities, and the various national and international legislative efforts to combat this environmental problem. They recommend future research directions necessary for a comprehensive understanding of this environmental issue and the development of efficient management strategies. This book addresses scientists, and it provides a solid knowledge base for policy makers, NGOs, and the broader public.

Description: Anthropogenic litter contamination of the oceans is a global problem of growing concern and currently receives strongly increasing attention by policy makers, public authorities, media and the general public. Unlike many other pollutants, marine litter on beaches and its deleterious effects on marine mammals, birds and turtles have attracted much attention as they can be directly observed by stakeholders.

Description: Plastic production and plastic waste have increased to such an extent that it has become globally ubiquitous. Recent research has highlighted that it has also invaded remote Polar Regions including the Arctic, where it is expected to accumulate over time due to transport from distant sources, rising local anthropogenic activities and increasing fragmentation of existing ocean plastics to microplastics (plastic items 〈5 mm). While a growing body of research has documented microplastics in the atmosphere, cryosphere, sea surface, water column, sediments and biota, contamination levels on Arctic beaches are poorly known. To fill this knowledge gap, we engaged citizen scientists participating in tourist cruises to sample beach sediments during shore visits on Svalbard, Norway. Following drying, sieving, and visual inspection of samples under a binocular microscope, putative plastic particles ≥1 mm were analysed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Plastic particles ≥1 mm were found in two out of 53 samples from 23 beaches (mean: 196.3 particles kg−1 and 147.4 particles L−1). These pollution levels could be due to our focus on plastic particles ≥1 mm as well as the relatively small sample sizes used during this initial phase of the project. In addition, the coarse substrate on most beaches might retain fewer plastic particles. The two samples with plastic particles ≥1 mm contained six polyester-epoxide particles and 4920 polypropylene fibres. The latter likely originated from a fishing net and points to possibly accelerated plastic fragmentation processes on Arctic beaches. Since fisheries-related debris is an important source of plastic on Svalbard, a build-up of microplastic quantities can be expected to burden Arctic ecosystems in addition to climate change unless efficient upstream action is taken to combat plastic pollution.