Mangroves are various types of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes 25° N and 25° S. The remaining mangrove forest areas of the world in 2000 was 53,190 square miles (137,760 km²) spanning 118 countries and territories. The word is used in at least three senses: (1) most broadly to refer to the habitat and entire plant assemblage ormangal,[page needed] for which the terms mangrove forest biome, mangrove swamp and mangrove forest are also used, (2) to refer to all trees and large shrubs in the mangrove swamp, and (3) narrowly to refer to the mangrove family of plants, the Rhizophoraceae, or even more specifically just to mangrove trees of the genus Rhizophora. The term “mangrove” comes to English from Spanish (perhaps by way of Portuguese), and is likely to originate from Guarani[disambiguation needed]. It was earlier “mangrow” (from Portuguese mangue or Spanish mangle), but this was corrupted via folk etymology influence of “grove“.
The mangrove biome, or mangal, is a distinct saline woodland or shrubland habitat characterized by depositional coastal environments, where fine sediments (often with high organic content) collect in areas protected from high-energy wave action. Mangroves dominate three-quarters of tropical coastlines. The saline conditions tolerated by various mangrove species range from brackish water, through pure seawater (30 to 40 ppt(parts per thousand)), to water concentrated by evaporation to over twice the salinity of ocean seawater (up to 90 ppt).
An increase in mangroves has been suggested for climate change mitigation.
Approximately 35% of mangrove area was lost during the last several decades of the 20th century (in countries for which sufficient data exist), which encompass about half of the area of mangroves. The United Nations Environment Program & Hamilton (2013), estimate that shrimp farming causes approximately a quarter of the destruction of mangrove forests.  Likewise, the 2010 update of the World Mangrove Atlas indicated a fifth of the world’s mangrove ecosystems have been lost since 1980.
Grassroots efforts to save mangroves from development are becoming more popular as their benefits become more widely known. In the Bahamas, for example, active efforts to save mangroves are occurring on the islands of Bimini and Great Guana Cay.