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• For your purchases, use cloth bags.
• Make responsible use of heating and keep the thermostat as low as possible.
• Commitment to sustainable food.

SDG 14 – Life below Water

Oceans and seas cover 71% of the Earth's surface and store 97% of the water in the hydrosphere.
However, the general public's knowledge of the structure and function of marine ecosystems is

lower than that of terrestrial ecosystems. Although in the past they were interpreted as an
inexhaustible source of resources, including food, energy or minerals, the reality is that the oceans
can be considered a desert for most of their surface area in terms of biological productivity
(amount of organic matter produced by plants per unit area per year). The oceans produce
approximately 1/3 of the organic matter generated annually on the planet, with an uneven
distribution between open ocean areas (90% of the ocean surface and 75% of the oceanic

production) and that of coastal areas, reefs, upwelling areas and kelp beds (together 10% of the
ocean surface and 25% of the organic matter production). In the open ocean, each plant has a
large amount of space. For example, temperate forests have a biomass of approximately 30 kg/m 2
or estuaries 2 kg/m while the open ocean has an average of 0.003 kg/m . It seems that the
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oceans are not particularly important places for life, yet they are home to 90% of the Earth's
biodiversity and, among other ecosystem services, regulate the climate, provide oxygen to the
atmosphere and protein-rich food for mankind. There is therefore ample reason for basic

education and public outreach to raise awareness of how the oceans influence our lives and how
humans influence the oceans.
● Human Impacts on the World Ocean

Humanity's negative impacts on the oceans causing biodiversity loss in the oceans can be divided
into 4 main groups according to Luypaert et al. (2020):

1. Habitat destruction and modification. It has a relative importance of 37% as a stressor on
threatened marine species. It is particularly important in areas of intensive use of ocean
resources.
2. Overfishing. It contributes in the order of 24%. In general, it is one of the impacts whose solution

is apparently the most feasible, due to the high resilience of fish stocks and the growth of
aquaculture in recent decades. Thus, according to the SOFIA report on the state of world fisheries
and aquaculture (FAO 2022), aquaculture production currently has values similar to those of
capture fisheries, whereas two decades ago it represented approximately one third of the
production of fish and fish by-products.

3. Pollution. It has a relative importance of around 15%. At present, it is particularly pollution
caused by plastics (Bonnano 2022). At the current rate (about 8 million tonnes of plastic end up

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