Biodiversity: Major Ecosystems of ACG

Overview: the four major ecosystems

ACG biodiversity may be conveniently partitioned into four of the five major tropical ecosystems: marine, dry forest, cloud forest and rain forest (there is no desert).  However, many of ACG’s 375,000+ species move back and forth among various parts of these four ecosystems, while many other species stay home.

Composite of separate photographs of dry forest, cloud forest, marine and rain forest, and a photograph of desert with an X across it because it does not occur in the ACG

Clockwise from upper left: Cloud forest (Volcan Cacao), marine (waters off Santa Elena Peninsula), rain forest (Rincon Rainforest), no desert, and dry forest (here shown as older secondary forest, formerly pasture, in Santa Rosa in the dry season).

A map of ACG in Costa Rica zoned into four major ecosystems

Pale blue, marine. Yellow, dry forest. Dark blue, cloud forest. Green, rain forest. These four ecosystems have been subdivided by the science and agricultural guilds into a variety of taxonomic schemes, with the 11 of the Holdridge Life Zone system being perhaps the best known. However, this system was actually developed to aid the agroscape in planning for crop yields, so it only very approximately maps what would be revealed by truly detailed biodiversity understanding of ACG. Equally in the dark are the potential sub-surface marine groupings of habitats and ecosystems, but these will not be clarified for ACG until many years of detailed inventory have been conducted in Sector Marino.

A map of ACG in Costa Rica zoned into the habitat-classification scheme called Holdridge Life Zones

The largest amount of seemingly intact forest is inside the ACG cloud forests and rain forest slopes, above about 700 m elevation and in certain areas.  Except for a very few exceptional small patches, the remainder has suffered direct assault by modern humans for 0-400 years.