The intensive concentration of population and excessive exploitation of natural resources puts enormous pressure on coastal ecosystems leading to biodiversity loss, habitats destruction, pollution, as well as conflicts between potential uses, and space congestion problems” (1).

In 2017, the European Environmental Agency published the report ‘State of Europe’s seas’. The results clearly reflect that intensive human activities are causing serious disturbances on and pollution of coastal zones and seas (2):

• Fishing occurs over a wide spatial area and is the main activity that causes seafloor damage. The impact of human activities affecting the deep seafloor is of increasing concern. Currently, most (74%) of the EU's fishing fleet effort results from mobile gears which disturb the seafloor.
• Due to the partial decrease in fishing pressure since 2007, some stocks in the North-east Atlantic Ocean and Baltic Sea are now exploited at sustainable levels. In the Mediterranean and Black Seas, the majority of commercially-fished species remain overfished. Fishing affects the wider ecosystem beyond fish stocks. It causes changes to ecosystem structure and functioning, altering species interactions and ecosystem resilience.
• Non-indigenous species (NIS) that become invasive are a key threat to biodiversity and ecosystem health. Their impacts are generally widespread and irreversible. The number of NIS in European waters continues to increase, with around 320 new species observed since 2000. More than 1 400 non-indigenous marine species have been introduced in Europe's seas. The main pathway of introduction is shipping followed by aquaculture-related activities.
• Eutrophication continues to be a major environmental problem. It is responsible for widespread environmental degradation in the Baltic and Black Seas. Oxygen-depleted zones are a serious and growing consequence of eutrophication. The environmental problems created by eutrophication reduce the quality of ecosystem services.
• Hazardous substances are widespread in the marine environment, due to the persistent nature of many substances and the continuous introduction of new ones. Targeted policy efforts have led to a reduction in the use of some of these contaminating substances, and some substances have been banned. Unfortunately, there are many more substances in the environment where the status is not known. Hazardous substances can accumulate through the marine food chain and can pose health risks to humans who regularly consume significant amounts of seafood.
• Marine litter — and plastic in particular — is accumulating in the world's oceans. European seas are also experiencing this problem. Most of the litter comes from land-based sources, except in the North-East Atlantic where sea-based litter is equally important. Micro-plastics are of growing concern because they build up in the food web. Their effects on wildlife and the risk they pose to human health are still poorly understood.
• Europe's seas are increasingly the site of industrial activities (e.g. shipping, renewable energy, oil and gas extraction, and defence activities). This results in increased underwater sound — the most widespread kind of energy introduced by man. Underwater noise can cause a range of impacts in marine animals, from subtle behavioural changes to injuries and death in extreme cases.

Coastal zones and seas are also among the most vulnerable areas to climate change and natural hazards. Risks include flooding, erosion, sea level rise as well as extreme weather events. These impacts are far reaching and are already changing the lives and livelihoods of coastal communities.