 Only the lush island of Fuvammulah produces fruits such as oranges and pineapples - partly because the terrain of Fuvammulah sits higher than most other islands, leaving the groundwater less subject to seawater penetration.However, as population grows, even in this island the cultivated areas are shrinking rapidly.Freshwater floats in a layer known as "Ghyben/Herzberg lens" above the seawater that permeates the limestone and coral sands of the islands.