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Galderic Lastras

Bio: Galderic Lastras is an academic researcher from University of Barcelona. The author has contributed to research in topics: Submarine canyon & Canyon. The author has an hindex of 33, co-authored 81 publications receiving 3530 citations. Previous affiliations of Galderic Lastras include National Oceanography Centre, Southampton & University of Malta.


Papers
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Journal ArticleDOI
30 Apr 2014-PLOS ONE
TL;DR: Litter was found to be present in the deepest areas and at locations as remote from land as the Charlie-Gibbs Fracture Zone across the Mid-Atlantic Ridge and on ocean ridges.
Abstract: Anthropogenic litter is present in all marine habitats, from beaches to the most remote points in the oceans. On the seafloor, marine litter, particularly plastic, can accumulate in high densities with deleterious consequences for its inhabitants. Yet, because of the high cost involved with sampling the seafloor, no large-scale assessment of distribution patterns was available to date. Here, we present data on litter distribution and density collected during 588 video and trawl surveys across 32 sites in European waters. We found litter to be present in the deepest areas and at locations as remote from land as the Charlie-Gibbs Fracture Zone across the Mid-Atlantic Ridge. The highest litter density occurs in submarine canyons, whilst the lowest density can be found on continental shelves and on ocean ridges. Plastic was the most prevalent litter item found on the seafloor. Litter from fishing activities (derelict fishing lines and nets) was particularly common on seamounts, banks, mounds and ocean ridges. Our results highlight the extent of the problem and the need for action to prevent increasing accumulation of litter in marine environments.

488 citations

Journal ArticleDOI
TL;DR: A review and update from original data and literature reports the current state of knowledge of Storegga, Traenadjupet and Finneidfjord slides from the mid-Norwegian margin, Afen Slide from the Faeroe-Shetland Channel, BIG'95 Slide and Central Adriatic Deformation Belt (CADEB) from continental slope and inner continental shelf settings off the Ebro and Po rivers in the Mediterranean Sea, Canary Slide west of the westernmost, youngest Canary Islands and Gebra Slide off the northern tip of the Antarctic Peninsula

337 citations

Journal ArticleDOI
13 Sep 2012-Nature
TL;DR: It is found that trawling-induced sediment displacement and removal from fishing grounds causes the morphology of the deep sea floor to become smoother over time, reducing its original complexity as shown by high-resolution seafloor relief maps.
Abstract: Bottom trawling is a fishing technique whereby heavy nets and gear scrape along the sea bed, and is shown here to disturb sediment fluxes and modify the sea floor morphology over large spatial scales. The direct impact of bottom trawling on local fish populations has received much attention, but trawling also affects other aspects of the ocean environment. This paper shows that bottom trawling — a commercial practice in which heavy nets and gear are dragged along the ocean floor — induces sediment reworking and erosion, causing the gradient of the sea floor to become smoother over time. This reduces the morphological complexity of deep-sea environments. The authors draw parallels between the effects of bottom trawling at sea and intensive agriculture on land, with the important difference that, on land, ploughing takes place once or twice a year, whereas, at sea, bottom trawling can be a frequent occurrence. Bottom trawling is a non-selective commercial fishing technique whereby heavy nets and gear are pulled along the sea floor. The direct impact of this technique on fish populations1,2 and benthic communities3,4 has received much attention, but trawling can also modify the physical properties of seafloor sediments, water–sediment chemical exchanges and sediment fluxes5,6. Most of the studies addressing the physical disturbances of trawl gear on the seabed have been undertaken in coastal and shelf environments7,8, however, where the capacity of trawling to modify the seafloor morphology coexists with high-energy natural processes driving sediment erosion, transport and deposition9. Here we show that on upper continental slopes, the reworking of the deep sea floor by trawling gradually modifies the shape of the submarine landscape over large spatial scales. We found that trawling-induced sediment displacement and removal from fishing grounds causes the morphology of the deep sea floor to become smoother over time, reducing its original complexity as shown by high-resolution seafloor relief maps. Our results suggest that in recent decades, following the industrialization of fishing fleets, bottom trawling has become an important driver of deep seascape evolution. Given the global dimension of this type of fishery, we anticipate that the morphology of the upper continental slope in many parts of the world’s oceans could be altered by intensive bottom trawling, producing comparable effects on the deep sea floor to those generated by agricultural ploughing on land.

328 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used the Liropus 2000 ROV to detect litter in three large submarine canyons of the NW Mediterranean Sea, namely Cap de Creus, La Fonera and Blanes canyours, at depths ranging from 140 to 1731m.

157 citations

Journal ArticleDOI
TL;DR: In this article, the authors present the first complete sidescan sonar dataset of the Nazare and Setubal Canyons, west Iberian margin, which, in combination with multibeam bathymetry, shallow seismic profiles and precise piston coring of intra-canyon targets, are used to characterise the sedimentary dynamics of these deep-sea settings.

136 citations


Cited by
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Journal ArticleDOI
TL;DR: Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, this work shows a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density.
Abstract: There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.

2,078 citations

Journal ArticleDOI
TL;DR: This review critically evaluates the current literature on the presence, behaviour and fate of microplastics in freshwater and terrestrial environments and, where appropriate, draws on relevant studies from other fields including nanotechnology, agriculture and waste management.

1,864 citations

Journal ArticleDOI
TL;DR: The sources and global distribution of microplastics in the environment, the fate and impact on marine biota, especially the food chain are described and the control measures discussed are those mapped out by both national and international environmental organizations for combating the impact from microplastic pollution.

1,487 citations

Journal ArticleDOI
TL;DR: It is shown that deep-sea sediments are a likely sink for microplastics, and the dominance of microfibres points to a previously underreported and unsampled plastic fraction.
Abstract: Marine debris, mostly consisting of plastic, is a global problem, negatively impacting wildlife, tourism and shipping. However, despite the durability of plastic, and the exponential increase in its production, monitoring data show limited evidence of concomitant increasing concentrations in marine habitats. There appears to be a considerable proportion of the manufactured plastic that is unaccounted for in surveys tracking the fate of environmental plastics. Even the discovery of widespread accumulation of microscopic fragments (microplastics) in oceanic gyres and shallow water sediments is unable to explain the missing fraction. Here, we show that deep-sea sediments are a likely sink for microplastics. Microplastic, in the form of fibres, was up to four orders of magnitude more abundant (per unit volume) in deep-sea sediments from the Atlantic Ocean, Mediterranean Sea and Indian Ocean than in contaminated sea-surface waters. Our results show evidence for a large and hitherto unknown repository of microplastics. The dominance of microfibres points to a previously underreported and unsampled plastic fraction. Given the vastness of the deep sea and the prevalence of microplastics at all sites we investigated, the deep-sea floor appears to provide an answer to the question-where is all the plastic?

1,292 citations

Book
24 Feb 2011
TL;DR: The Global River Database as mentioned in this paper is a collection of river data from North and Central America, South America, Europe, Africa, Asia, and Oceania with a focus on flooding and erosion.
Abstract: Foreword 1. Introduction 2. Runoff, erosion and delivery to the coastal ocean 3. Temporal variations 4. Human impacts Appendices. Global River Database: Appendix A: North and Central America Appendix B: South America Appendix C: Europe Appendix D: Africa Appendix E: Eurasia Appendix F: Asia Appendix G: Oceania References Index.

1,046 citations