30 by 3030 by 30 (or 30x30) is a worldwide initiative for governments to designate 30% of Earth's land and ocean area as protected areas by 2030. The target was proposed by a 2019 article in Science Advances, "A Global Deal for Nature: Guiding principles, milestones, and targets", highlighting the need for expanded nature conservation efforts to mitigate climate change. Launched by the High Ambition Coalition for Nature and People in 2020, more than 50 nations had agreed to the initiative by January 2021, which has increased to more than 100 countries by October 2022.
Great Barrier ReefThe Great Barrier Reef is the world's largest coral reef system, composed of over 2,900 individual reefs and 900 islands stretching for over over an area of approximately . The reef is located in the Coral Sea, off the coast of Queensland, Australia, separated from the coast by a channel wide in places and over deep. The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps.
Marine biologyMarine biology is the scientific study of the biology of marine life, organisms in the sea. Given that in biology many phyla, families and genera have some species that live in the sea and others that live on land, marine biology classifies species based on the environment rather than on taxonomy. A large proportion of all life on Earth lives in the ocean. The exact size of this large proportion is unknown, since many ocean species are still to be discovered. The ocean is a complex three-dimensional world covering approximately 71% of the Earth's surface.
TideTides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can be used for any given locale to find the predicted times and amplitude (or "tidal range"). The predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide (pattern of tides in the deep ocean), the amphidromic systems of the oceans, and the shape of the coastline and near-shore bathymetry (see Timing).
Territorial watersTerritorial waters are informally an area of water where a sovereign state has jurisdiction, including internal waters, the territorial sea, the contiguous zone, the exclusive economic zone, and potentially the extended continental shelf. In a narrower sense, the term is often used as a synonym for the territorial sea. Vessels have different rights and duties when passing through each area defined by the United Nations Convention on the Law of the Sea (UNCLOS), one of the most ratified treaties.
SeagrassSeagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the order Alismatales (in the clade of monocotyledons). Seagrasses evolved from terrestrial plants which recolonised the ocean 70 to 100 million years ago. The name seagrass stems from the many species with long and narrow leaves, which grow by rhizome extension and often spread across large "meadows" resembling grassland; many species superficially resemble terrestrial grasses of the family Poaceae.
Exclusive economic zoneAn exclusive economic zone (EEZ), as prescribed by the 1982 United Nations Convention on the Law of the Sea, is an area of the sea in which a sovereign state has exclusive rights regarding the exploration and use of marine resources, including energy production from water and wind. It stretches from the outer limit of the territorial sea (12 nautical miles from the baseline) out to 200 nautical miles (nmi) from the coast of the state in question. It is also referred to as a maritime continental margin and, in colloquial usage, may include the continental shelf.
Biodiversity lossBiodiversity loss includes the worldwide extinction of different species, as well as the local reduction or loss of species in a certain habitat, resulting in a loss of biological diversity. The latter phenomenon can be temporary or permanent, depending on whether the environmental degradation that leads to the loss is reversible through ecological restoration/ecological resilience or effectively permanent (e.g. through land loss).
