Story 04 Oct, 2024

World Heritage: Recognising the value of Geodiversity on the global stage

Active Volcanoes. Vast Deserts. Underwater Caves. On this International Geodiversity Day (6 October), IUCN puts the spotlight on just a few of the remarkable examples of geodiversity on Earth. Geodiversity refers to the variety of geological and physical elements of nature, such as minerals, rocks, soils, fossils and landforms, and the active geological and geomorphological processes that shape them.

Geodiversity can provide us with a window into the past- a time before humans and when the environments and ecosystems we appreciate and work to protect today were only just being established.  Geodiversity is essential in supporting and sustaining some of the most species-rich and biodiverse ecosystems in the world. Areas of high geodiversity are often associated with the highest levels of species richness on a global scale. The heterogeneous environments that geodiversity lays the foundations for, enable the creation of multiple different ecological niches, habitats and resources for species to coexist. 

The World Heritage Convention celebrates globally outstanding and unique geodiversity with sites given World Heritage status for their important geological and geomorphological values. These sites could be considered landmarks of prehistoric ages, the ‘Colosseum’ of the Jurassic or the ‘Taj Mahal’ of the Cambrian. The World Heritage Convention (and IUCN through its advisory body role) recognises the intrinsic and irreplaceable value of geodiversity to humanity globally.

There are currently 99 World Heritage sites listed for their outstanding geological importance (under criterion (viii)), representing more than 40% of all sites inscribed for their nature conservation values. There are, however, more sites where geodiversity plays a crucial role in underpinning the natural and cultural values in other World Heritage sites.

Examples of World Heritage sites showcasing geoheritage include:

Joggins Fossil Cliffs, Canada, is said to be the best and most complete known fossil record of terrestrial life from the ‘Coal Age’ (Carboniferous Period c. 360 to 300 million years ago).

Phong Nha-Ke Bang National Park, Viet Nam, is a striking landscape formed of extensive and complex karst developments, including the world’s largest cave passage in terms of diameter and continuity.

The Tajik National Park (Mountains of the Pamirs), Tajikistan, demonstrates a diversity of geomorphological features within one protected area (high mountains, valley glaciers, deep river gorges and cold continental desert). This includes likely the youngest deepwater alpine lake in the world.

The Badain Jaran Desert - Towers of Sand and Lakes, China, is home to an abundance of striking interdunal lakes of a myriad of colours caused by the unique salinity and microbial communities of each lake.

Geodiversity and biodiversity

Geology and geomorphological processes are diverse in themselves, but they also influence biodiversity. In many coastal zones for example, geodiversity underpins biodiversity because of the dependence of organisms on the food resources in the substrates that are directly associated with geological and oceanographical processes. Virunga National Park World Heritage property in the Democratic Republic of the Congo also highlights the interdependence between the geodiversity and biodiversity. The Great Rift Valley and the emergence of the Virunga massif (comprising eight volcanoes including two of the most active in Africa) have set the stage for some of the greatest biodiversity on the African continent. Home to more endemic vertebrate species than any other African region and over 2000 plant species, Virunga is likely the most biodiverse protected area in Africa.  

IUCN’s work to support geodiversity

IUCN plays an important role in ensuring that the most important geodiversity is conserved globally. IUCN advises the World Heritage Committee on the nominations of new geological sites (including through its guidance documents on Geological World Heritage) and the monitoring of the state of conservation of existing geological World Heritage sites. IUCN also has a long-standing role supporting the UNESCO Global Geoparks Network since its establishment in 2004 and is a non-voting member of the UNESCO Global Geoparks Council. The IUCN World Heritage team collaborates with the International Union of Geological Sciences, International Association of Geomorphologists and the IUCN WCPA Geoheritage Specialist Group to publish several best practice guidelines for geoconservation and to preserve geoheritage for future generations of humanity everywhere to appreciate. These collaborations have most recently included efforts towards a future Key Geoheritage Areas Initiative- an initiative to promote geoconservation across the world through recognising and conserving geoheritage of international significance. IUCN also supports the International Geodiversity Day as proclaimed by UNESCO

About IUCN and the World Heritage Convention

Since the inception of the World Heritage Convention in 1972, IUCN has played a unique role as the official advisory body under the World Heritage Convention on natural World Heritage. This involves leading the technical recommendation of all new nominations of natural and mixed World Heritage sites, monitoring the status of existing natural and mixed World Heritage sites and the newly added Preliminary Assessment process to provide direct advice on the feasibility of potential nominations to states parties.

IUCN also works independently on the Convention to support World Heritage sites globally though our extensive network of programs and policies led though our central Secretariat team, our expert commissions, and our member organisations.

Find out more about IUCN's work on World Heritage here.