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Posts tagged Barrier Island

Coral Reefs by Bajuni Archipelago, Somalia

0.9S 42.0E

June 15th, 2009 Category: Snapshots

Somalia - June 3rd, 2009

Somalia - June 3rd, 2009

Somalia is the African country with the longest national coastline, at 3025 km, with an estimated shelf area (depth 0–200 m) of 32 500 km2.

From Ras Caseyr to the Kenya border, the coast runs north-east to south-west. An important feature found along the southern Somali shoreline is the Bajuni Archipelago in the Indian Ocean.

This archipelago consists of islands, islets and skerries, forming a barrier island separated from the coast by a narrow marine sound, from Kismayu to Ras Kiyamboni.

They lie at the northern end of a string of reefs which also include Zanzibar and Pemba. There are six main islands: Chandra, Chovaye, Chula (the only island with a significant population), Koyama, Darakasi and Ngumi.

Areas such as this along the southern Somali coast form part of the Somali Current Large Marine Ecosystem, encompassing 700 000 km2, and extending 800 km between Dar es Salaam and Ras Hafun. Abundant biomass develops here due to upwelling.

The shelf area has a wide variety of coral reefs, mangroves, seagrass meadows, beaches and estuaries. In shallow water areas the abraded flats are colonized by scattered coral communities with variable cover. A true fringing reef is achieved in places only in the Bajuni Archipelago, and around the Bajuni barrier island there is more diversity.

Large-scale alteration produced by man on the Somali coast is relatively recent, but has accelerated in the last few decades, especially around major cities. This alteration affects especially backshore areas where the Pleistocene coral reefs are quarried.

At present, the continental shelf is not adequately monitored or protected, so coastal habitats are being degraded, living marine resources are overexploited, and pollution levels are increasing, all of which affect natural resources and biodiversity, reports the Marine Pollutin Bulletin.

Mobile and Perdido Bays, USA

30.7N 88.2W

June 8th, 2009 Category: Rivers

Mobile Bay, Alabama, USA - June 2nd, 2009

Mobile Bay, Alabama, USA - June 2nd, 2009

Two bays can be seen draining into the Gulf of Mexico: Mobile Bay, in the center, and Perdido Bay, on the right. Here, the former is spilling a greater quantity of brown sediments into the gulf. On the left side of the image, several condensation trails are visible over land.

Mobile Bay is an inlet lying within the state of Alabama in the USA. Its mouth is formed by the Fort Morgan Peninsula on the eastern side and Dauphin Island, a barrier island, on the western side.

Mobile Bay is 413 square miles (1,070 km2) in area. It is 31 miles (50 km) long by a maximum width of 24 miles (39 km).

It is the fourth largest estuary in the United States, with a discharge of 62,000 cubic feet (1,800 m3) of water per second.

The deepest areas of the bay are located within the shipping channel, sometimes in excess of 75 feet (23 m) deep, but the average depth of the bay is 10 feet (3 m).

The Mobile River and Tensaw River empty into the northern end of the bay, making it an estuary. Several smaller rivers also empty into the bay: Dog River, Deer River, and Fowl River on the western side of the bay, and Fish River on the eastern side.

Perdido Bay is a bay draining the Perdido River that lies on the borders of Baldwin County, Alabama and Escambia County, Florida. It lies west of the Florida communities of Pensacola and Perdido Key and east of the Alabama communities of Orange Beach and Lillian.

Ono Island and the mouth of the bay are within Alabama territory, as the Florida border crosses the barrier islands just east of Perdido Pass and Alabama Point, where the bay empties into the Gulf of Mexico.