2,436 articles
Lúrio
Lúrio (Rio Lúrio, Lurio River), a roughly 500–593 km river in northern Mozambique draining Niassa, Cabo Delgado, Nampula, and Zambézia; its ~61,000 km² basin is the largest entirely within Mozambique, emptying into Baía do Lúrio.
Lystad Bay
Lystad Bay: bay 2.5 mi wide on the west side of Horseshoe Island, NE Marguerite Bay, Antarctica; named for Capt. Isak Lystad, first surveyed 1936-37 by the BGLE, site of the Turkish Science Base.
Lythrum salicaria
Lythrum salicaria (purple loosestrife) is a Eurasian wetland perennial, invasive in North America since the early 1800s, tristylous, producing up to 2.5 million seeds per plant and forming dense stands; its ecological impacts are debated.
M'Clure Strait
M'Clure Strait, an arm of the Beaufort Sea in Canada's Northwest Territories, is the western leg of Parry Channel in the Northwest Passage, named for explorer Robert McClure; about 270 km long, first transited by icebreakers in 1954.
Mackay
Mackay: Lake Mackay (Wilkinkarra), a large ephemeral salt lake on the Western Australia–Northern Territory border, Australia's fourth largest salt lake, named for explorer Donald Mackay, and site of a proposed potash project.
Mackenzie Bay
Mackenzie Bay, the Arctic bay off the Mackenzie River mouth in the Canadian Beaufort Sea (Yukon/NWT), brackish, sediment-rich, a beluga management zone; also an Antarctic bay on the Amery Ice Shelf.
Mackenzie River
The Mackenzie River drains Great Slave Lake to the Arctic Ocean through Canada's largest basin, about 1.8 million km2. Explored by Alexander Mackenzie in 1789 (Dene name Deh-Cho), it is the fourth-largest circumpolar river by discharge.
Macquarie
Macquarie River (Wambuul Macquarie), NSW inland river rising near Bathurst, flowing northwest to the Barwon; named for Governor Lachlan Macquarie; feeds Burrendong Dam and the Macquarie Marshes. Distinct from Port Macquarie and Tasmania's Macquarie River.
Macquarie Marshes
Macquarie Marshes: ~200,000 ha intermittently flooded wetland complex on the lower Macquarie River, NSW, Australia; Ramsar-listed (19,850 ha, 1986/2000/2012); degraded by river regulation since Burrendong Dam (1967).
Macquarie Ridge
The Macquarie Ridge is a submarine ridge in the Southern Ocean, running about 1,600 km from the Puysegur Trench south of New Zealand along the Australian-Pacific plate boundary.
Madagascar Eastern Highlands
Madagascar Eastern Highlands, FEOW ecoregion 581, a narrow north-south freshwater ecoregion covering the upper reaches of Madagascar's eastern coastal rivers above 200 m, with endemic Bedotia rainbowfishes, cichlids, and about 130 aquatic frog species.
Madagascar Eastern Lowlands
Madagascar Eastern Lowlands, FEOW ecoregion 583, a narrow coastal strip of tropical and subtropical coastal rivers draining to the Indian Ocean, with 69 native fish species, Bedotia endemics, Astacoides crayfish, and brackish lagoons.
Madeira Abyssal Plain
Madeira Abyssal Plain: flat 68,000 km² deep-sea plain in the Canary Basin, NE Atlantic, over 5400 m deep, built of turbidites from NW Africa, the Canaries, and nearby seamounts; studied for ODP Leg 157 and radioactive waste disposal.
Madeira River
Madeira River, largest Amazon tributary (Mamoré + Beni at Villa Bella), ~1,200 km to the Amazon; whitewater, ~430 Mt/yr sediment, Santo Antônio and Jirau dams, record 2014 flood and 2024 drought.
Madre de Dios
Madre de Dios, also Rio Madre de Dios, is a roughly 965 km Andes-to-Amazon river in southeastern Peru and Bolivia, a Madeira tributary; its Peruvian department, capital Puerto Maldonado, was created in 1912 and faces gold-mining mercury contamination.
Mae Khlong
Mae Khlong (แม่น้ำแม่กลอง), a ~140 km river in western Thailand formed by the Khwae Yai and Khwae Noi, flowing through Kanchanaburi, Ratchaburi, and Samut Songkhram to the Gulf of Thailand; dammed by Srinagarind, Vajiralongkorn, and Mae Klong dams.
Magdalena - Sinu
Magdalena - Sinu, FEOW freshwater ecoregion 302, Colombia; combines the Magdalena, Cauca, and Sinu drainages flowing to the Caribbean Sea; ~233 fish species, 68% endemic, threatened by dams and deforestation.
Magdalena River
The Magdalena River (Río Magdalena), Colombia's principal river, runs about 1,540 km from the Páramo de las Papas to the Caribbean; its basin holds 80% of the population and it was the country's historic steamboat artery.
Mahakam
Mahakam (Sungai Mahakam), major river of East Kalimantan, Borneo, Indonesia, roughly 920–980 km long, draining 77,095 km² into the Makassar Strait; known for its fan-shaped mixed tide–fluvial delta, middle lakes, and the freshwater Pesut Irrawaddy dolphin.
Mahanadi (ମହାନଦୀ)
Mahäna Nadï (Mahanadi, ମହାନଦୀ, महानदी), 'great river' in Sanskrit, is a major east-flowing peninsular Indian river, 851 km long, rising in Chhattisgarh's Dhamtari district, flowing through Odisha, home of the Hirakud Dam, and draining to the Bay of Bengal.
Maho Beach
Maho Beach is a beach on the Dutch side of Sint Maarten at the end of Princess Juliana International Airport's runway, famous for planes passing low overhead.
Mai Po Marshes (米埔湿地)
Mai Po Marshes (米埔湿地) are a 380-hectare wetland nature reserve at Inner Deep Bay, Hong Kong, managed by WWF since 1983, Ramsar-listed in 1995, famed for gei wai shrimp ponds, mangroves, and wintering waterbirds including the black-faced spoonbill.
Mai-Ndombe (landform)
Lake Mai-Ndombe (Lac Mai-Ndombe), 'black water' in Kikongo, is Africa's largest humic black-water lake (~2,250 km2, ~4 m deep) in the Tumba-Ngiri-Maindombe wetland complex, Cuvette Centrale, DR Congo, draining via the Fimi River and emitting CO2, CH4, and N2O including millennial-aged peat carbon.
Main (river)
The Main, or River Main, is a river in Germany and the longest right tributary of the Rhine, formed by the Red Main and White Main and flowing through Franconia.
Majan Ridges
Majan Ridges, an Arabian Sea undersea feature classified as a ridge in the Marine Regions and GEBCO gazetteers, listed near the Murray Ridge, Kurma Ridge, Khanjar Ridge, Oman Basin, and Oman Abyssal Plain.
Makarov Basin
Makarov Basin, wedge-shaped deep Arctic Ocean basin between the Lomonosov Ridge and Alpha-Mendeleev Ridge, discovered 1962 by ARLIS II; over 500 km wide, up to 3,940 m deep, largely filled with Eurasian Basin water.
Makassar Strait
Makassar Strait (Selat Makassar), sea passage between Borneo and Sulawesi, Indonesia, linking the Celebes and Java Seas; carries ~77% of the Indonesian Throughflow (~12–13 Sv) and is an active tectonic and shipping corridor.
Mälaren
Mälaren, or Lake Mälaren, is Sweden's third largest lake, west of Stockholm, with over 8,000 islands and UNESCO Viking-Age Birka; it supplies drinking water to about two million people.
Malay Peninsula Eastern Slope
Malay Peninsula Eastern Slope (FEOW ecoregion 734) is a freshwater ecoregion of eastern Peninsular Malaysia drainages from Prachuap Khiri Khan, Thailand to Singapore, a Sundaic fauna transition zone and identified freshwater fish conservation priority.
Malebo Pool
Malebo Pool (formerly Stanley Pool) is a 35-km-long, lake-like widening of the Congo River between the DRC and Republic of the Congo, with Kinshasa and Brazzaville on opposite shores, formed by a rock-sill barrier above the lower Congo rapids.