The map shows landcover and vegetation impact of the Hunga Tonga Hunga Haápai volcanic eruption on the Tonga Island group.
Washington Island (Teraina) in the Northern Line Islands is a small atoll with a land area of 14.2 sq. km. situated at 4° 4 3'N, 160° 25'W. The Northern Line Island archipelago is comprised of four islands alined on an axis which runs from Christmas Island, just north of the equator, to Palmyra Island in the northwest (Figure 1). Washington Island, and its nearest neighbor Fanning Island, about 150 kilometers to the south east, have had close economic and social ties for most of their recent history.
During the period 1958-1964, the authors undertook soil and vegetation studies in the northern Marshall Islands as part of the University of Washington Radiation Biology Laboratory surveillance team. This team was responsible for monitoring levels of radiation in various components of the island environment and any effects on plant and animal life. The authors of this report were charged with the soils and vegetation components but assisted with collections in the aquatic ecosystems and some food plant materials.
Phosphatic limestones and associated soils occur on eight of the nine islands of Tuvalu, central Pacific. Deposits range from gram-size to >500,000 tons. Carbonate hydroxyapatite, dahllite, forms crustose cement about calcareous bioclasts which it sometimes replaces. Precise genetic relationship of rock to soil is unclear. Consolidated rock occurs as hardpan within phosphatic soil profiles, with unconsolidated phosphatic layers above and below. Phosphatization has occurred either as a continuous or episodic process within the vadose zone for at least 4000 years.