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  The following Goggle satellite images taken between January 29, 2001, and June 21, 2010, document decreasing vegetation on the Island of Zanzibar over the past nine years.  Progressive deforestation is particularly noticeable on the western side of the island where trees have been harvested for building and a cottage industry exists to supply firewood and charcoal to urban areas along the coast.  Agriculture remains the primary industry in Zanzibar, and expanding cultivation of the island has resulted in further loss of forest lands.

  
  A majority of forests and vegetation are located in the western side of the island.  Because of cloud cover, it is harder to track vegetation in the middle of the island.  Forests located in the middle of the island include the Kiwengwa Pongwe Forest, Kichwele Forest Reserve, Muyuni Forest, and the Jozani Chwaka Bay National Park (including the Jozani Forest).  

Google Earth Image: June 29, 2001

Google Earth Image: June 21, 2002

Google Earth Image: April 16, 2003

Google Earth Image: July 4, 2004

Google Earth Image: September 2, 2005

Google Earth Image: June 12, 2006

Google Earth Image: June 23, 2007

Google Earth Image: October 21, 2008

Google Earth Image: June 29, 2009

Google Earth Image: June 21, 2010

  The following images are of Zanzibar city and Stone Town.  These are the largest urban areas on Zanzibar and contributes to the most deforestation on the island.

Google Earth Image: 2010 - Zanzibar City and Stone Town (zoomed out)

Google Earth Image: 2010 - closer view of Zanzibar city and Stone Town

  Also impacted are coastal areas where tourism is a growing industry.  Deforestation and increased use of concrete has led to higher temperatures and lower rainfall, leading to desertification.  The image below is of Bwejuu, a developing resort region on the island.

Google Earth Image: September 2, 2005

This image was taken off of the eastern coast of the island.

Google Earth Image: October 16, 2007

Within two years vegetation has noticeably decreased.  The border of Bwejuu has moved more inland and the white spot east of Bwejuu has increased, almost doubling in size. 

Google Earth Image: November 1, 2005

This image was taken off of the Southern Western Coast of Zanzibar.

Google Earth Image: June 18, 2009

The landscape of the area changed dramatically.  There is now a fairly developed town along the coast.  Also the areas from the 2005 image where vegetation was low or not present is now green and almost non-existent.  It should be noted that this area is within a protected area of Zanzibar.

Map off of Google Search: Shows vegetation on the island

This map shows that most of the vegetation is located on the western part of the island.  

This is an NDVI image taken from Glovis USGS (a density slice from ENVI was applied to the image)

This image confirms that most of the vegetation is located on the western part of the island. The color red represents the areas with heaviest vegetation.  The area outlined in black is a rough sketch of the protected area in Zanzibar according to the Glovis USGS data.

Image provided from an article from Myers. Please see references for article details.

This map outlines the fertile and urban areas on Zanzibar Island.  When compared to the NDVI image and Vegetation map above, the fertile area is the area with the most vegetation.  It is also the area with the highest population concentration.   

Image A

Image B

Image C

  The images above provide topographical data.  All of the images are from the Global Land Cover Facility using SRTM data.  Image A was enhanced after being put into ENVI.  The lightest areas represent the highest elevations and the darkest areas represent the lowest elevations.  Images B and C had a Density slice applied to them. Image C is a 3D model of image B.  In images B and C, the light blue areas represent an elevation of 75 meters or more above sea level. 

The island is generally flat.  The majority of the vegetation is located on the western part of the island which is also the area of highest elevation.  The high elevation may prevent cultivation in that area, limiting agriculture to a smaller area.  This may be the reason most of the urbanization is in the southern part of the fertile land (as seen in the map before the elevation data) and may possibly be one of the reasons why urbanization has expanded in the eastern coast.