Geodiversity: the often-forgotten half of nature
Murray Gray explains the importance of the often-forgotten abiotic or non-living half of nature and invites everyone to celebrate International Geodiversity Day on 6th October starting this year.
What do we think of when we think about nature? Trees, forests, wildflowers, certainly. Tigers, pandas, polar bears, perhaps? But important though these are, the fact is that living things - flora and fauna - are only half of nature. There’s another half to nature, an often-forgotten half, the physical foundations of the planet or the abiotic or non-living half. The Earth is often described as “third rock from the Sun” and that’s not a bad description because we live and rely on what is essentially a huge, almost spherical rock nearly 13,000 km in diameter, hurtling around the Sun at over 100,000 kilometres per hour, albeit with a surface cover of wildlife and 70 per cent ocean. But this huge rock is not uniform throughout. Not only does it have internal layers including core and crust, but the Earth’s crust itself has a huge variety of rock types and topographic variation reflecting its 4.6 billion-year history of moving plates, changing climates and a host of catastrophic events. Because our planet has been, and still is, a dynamic one reflected in frequent events at all scales from earthquakes, volcanic eruptions and tsunamis to coastal erosion, river flooding and landslides. This huge range of planetary rocks, topographies and processes has become known as “geodiversity”, but where did that name come from?
In 1992, at the Earth Summit held in Rio de Janeiro, the nation states of the world agreed a Convention on Biological Diversity (CBD). The impetus for this was concern over the loss of species, degradation of the world’s ecosystems and the need for conservation and sustainable use of the Earth’s biological resources for the benefit of present and future generations. The term “Biological Diversity” was subsequently shortened to “biodiversity”, and the Convention requires nation states to develop their own strategies, plans and programmes to implement the Convention including identifying and monitoring their biodiversity and the impacts affecting it across their whole territories. As a result of these activities there has been a huge upsurge not only in public understanding of the need for protection of species but also of the concept of “biodiversity” itself. Over 100 books have been published with “biodiversity” in the title and E.O. Wilson, often known as the father of
biodiversity, has stated that it poses “some of the most fundamental problems of the biological sciences”.
Shortly after the Earth Summit, geoscientists, realising that they too study diverse natural features that can also be subject to loss and degradation, started to use the term “geodiversity” to describe the variety of non-living or abiotic nature. Much of the early ideas on this were carried out in Tasmania, Australia, but over the last 20 years, this term and concept have come into common usage among the international geological community as the abiotic equivalent of “biodiversity”. But while “biodiversity” is now a well-used concept including among the general public, “geodiversity” is poorly recognised or understood in policy and public domains.
Geodiversity is defined as the variety of the non-living elements of nature – including its minerals, rocks, fossils, soils, sediments, landforms, topography, processes and hydrological features such as rivers, lakes and water chemistry. Geodiversity underpins biodiversity in providing the foundations and habitats for all living things, but it has its own values independent of biodiversity. Geodiversity is also essential to human well-being:
• it is the source of the (geo)materials that build our towns and cities;
• it provides our energy resources, including renewable energy and the materials mined to
manufacture wind turbines, solar panels, etc;
• it allows us to bury our waste, provides us with freshwater and attenuates our pollution by
filtering dirty water moving through rock and sediments towards the aquifer;
• it inspires our artists and provides us with incredible landscapes from mountains to coasts. • and some sites, known collectively as geoheritage, provide us with the evidence to
reconstruct the billions of years of history of our planet and the evolution of life on it.
• it gives us evidence of past climate and landscape changes and their causes and therefore
helps us to understand and plan for the impacts of future environmental changes.
• furthermore, geodiversity is fundamental to the implementation of many of the UN’s
Sustainable Development Goals and is crucial in understanding and promoting the sustainable use of the Earth’s physical resources.
Geodiversity and its significance for humanity are poorly recognised worldwide, and there is an urgent need to increase public understanding. Like biodiversity, many important geoheritage sites and features are at risk from human activities, and yet attempts at
geoconservation are limited in many countries. International cooperation is therefore essential to ensure proper recognition and management of the Earth’s geodiversity and geoheritage. For these reasons the United Nations Educational, Scientific and Cultural Organisation (UNESCO) has declared 6th October each year to be International Geodiversity Day starting this year, with further information available on the website www.geodiversityday.org.
On this day everyone is invited to organise or take part in the many geo-events taking place around the world or simply to reflect on how they benefit from living on a geodiverse planet. One of the clearest examples of this is a typical smartphone which contains over 60 different chemical elements, all of which play a different role in the phone and all of which have been extracted from the Earth’s crust. The fact is that our modern society simply could not exist without our planet’s geodiversity. So, celebrate geodiversity every day, but particularly on 6th October.
Prof Murray Gray,
School of Geography,
Queen Mary University of London