Deep Sea impact How Human activities affect the Deep Sea Ecosystem Mariano Peruzzo MRes Marine biology student 2015/2016 The Marine Biological Association of United Kingdom - The Laboratory, Citadel Hill, Plymouth PL1 2PB HISTORICAL ECOLOGY OF SEMI-ENCLOSED BASINS: PAST, PRESENT AND FUTURE OF SEAS AT RISK 3rd – 4th October 2016 Chioggia, Italy
Deep Sea Ocean is the largest ecosystem on the planet, covering 65% of the Earth's surface. Starting at about 200 m depth, where the continental shelf ends, down to the deepest trenches at almost 11000 m. It’s still one of the least studied ecosystems, but we now believe that there is high biodiversity and a possible wealth of resources [1].
Hypoxia in which dissolved oxygen is below the level necessary to sustain most animal life
Warming
Ocean Acidification
Acidity CO2
could affect early stages of calcifying species, if this proves negative, could also have a secondary effect on deep bottom fish stocks [2].
Dumping Area Being remote and unseen has encouraged, careless anthropogenic disposal of all sorts of waste, with unknown and uninvestigated effects on the habitats and their fauna [3].
Deep Bottom Fishing trawling and long lining, put a threat on species that are often long lived, with slow growth rates and delayed maturity. The efforts can be intense on small seamounts and cold seeps habitat, some of those not yet scientifically explored. By-catch of some gorgonian corals that exceed 4000 years of age has been evident and a reduction in biodiversity and biomass of benthic invertebrates are suspected [4] [5] .
Exploitation and Extractions need guidelines to increase safe commercial profiteering for all the mineral resources, such as deep drilling of oil and gas, frozen methane hydrate, manganese nodules, cobalt-rich crusts and seafloor massive sulfide (SMS) deposits at sites of hydrothermal venting [6]. Removing the top sediment and redepositing can smother abyssal communities [7].
Exploration has been mostly ignored until relatively recently. Total darkness, low temperatures, high pressure, and limited food availability create extreme conditions; scientists of the past thought that the deep-sea environment could not host life. But even scientific research contributes to deep sea-litter by dropping ballast weights, using moorings, submersibles and ROVs, temporary powerful lights, all impacting, to a lesser or larger degree.
Conclusions We know that business and greed can drive us to disproportionate side effects, with possibly few and only minor advancements, indicating we have acted mindlessly. It is imperative for science, community, industry and national and international organizations to conserve the fragile deep-sea ecosystem while developing successful exploitation and safe management of an ecosystem so largely unknown.
References [1] Ramirez-Llodra, E., et al. 2011. PLoS ONE [2] Hofmann, G.E., et al. 2010. Annual Review of Ecology, Evolution, and Systematics [3] Mordecai, G., et al. 2011 Deep Sea Research Part II, Topical Studies in Oceanography [4] Turley, C.M., et al. 2007. Coral Reefs [5] Callum, M.R., 2002. Trends in Ecology & Evolution [6] Boschen, R.E., et al. 2013. Ocean & Coastal Management [7] Mestre, N.C, et al. 2014. Environmental Pollution, Elsevier. Author's contact:
[email protected] Synopsis: Doi:10.1371/journal.pone.0022588.g00 Map from International Charter Series Mediterranean and Black Seas 4300 Produced by the Italian Hydrographic Institute, 1984.
