Secretary-General Ban Ki-moon Wednesday?called on all governments and peoples to play their part to ensure that the world's oceans are protected for future generations, warning that they face major threats in the years ahead.

In a statement issued to mark World Oceans Day, which is being celebrated around the globe on June 8, Mr. Ban outlined what he called "many severe challenges related to oceans.

"These range from depleted fishery resources, the impacts of climate change and the deterioration of the marine environment to maritime safety and security, labour conditions for seafarers and the increasingly important issue of migration by sea," he said.

"All activities and policies related to oceans and the marine environment need to acknowledge and incorporate the three pillars of sustainable development: environmental, social and economic. Only then can we achieve the development objectives set by the international community.

"I urge governments and all sectors of society to embrace our individual and collective responsibility to protect the marine environment and manage its resources in a sustainable manner for present and future generations."

Echoing the Secretary-General's comments, Irina Bokova, Director-General of the UN Educational, Scientific and Cultural Organization (UNESCO), said: "Knowledge of oceans has long been driven by the need to access and exploit their resources. This must change. The challenge today is to use marine science to understand and protect oceans, in order to better manage their ecosystems and biodiversity for present and future generations."

To mark the day, which has the theme of "Our oceans: greening our future," UNESCO and its Intergovernmental Oceanographic Commission (IOC) "join hundreds of aquariums, zoos, museums, conservation organizations, and thousands of individuals around the world celebrating the day by participating in fun, inspirational, and educational events," the agency said.

New York City authorities have announced that the iconic Empire State Building will be lit this evening in white, blue and purple, representing the different layers of the ocean.

The UN Environment Programme (UNEP) marked the Day by launching a report calling for new partnerships to ensure sustainable development for marine and coastal environments.

"Taking Steps toward Marine and Coastal Ecosystem-Based Management: An Introductory Guide" states that closer partnerships between different marine users – such as fishing communities, the tourism industry and conservationists – can also help coastal communities become better prepared for natural disasters and the impacts of global warming, such ocean acidification and changes in sea levels.

The report explains in simple language how sharing knowledge and best practices across different sectors can make marine management more effective, and offers guidance using over 20 case studies and success stories, ranging from polar ecosystems in Antarctica to atolls in the Indian Ocean.

"The future role of marine and coastal ecosystems in human well-being depends increasingly on developing the capacity of countries to manage human uses and impacts in order to ensure that ecosystem health and self-repairing capacity is not undermined," said UNEP Executive Director Achim Steiner.

"Central to a transformational response to decades of overfishing, pollution and unplanned urban development will be moving from sectoral marine and coastal management to a joined approach that marries seemingly competing interests," he added.