Article | Last updated: 2014-02-12 | Ministry of Climate and Environment
Tropical rainforests represent some of the world's most species-rich areas, and are also very vulnerable to extinctions and reduced biodiversity. The clearest threat to rainforest biodiversity is logging and deforestation.
Biodiversity - the variation and number of different animal and plant species, and how they interact, has become an important topic in national and international environmental debates. In Norway, biodiversity is protected by the 2009 Nature Diversity Act, but not all countries have formalised systems, and nature does not recognise national borders.
The UN has declared 2011-2020 the Decade on Biodiversity and is working to raise awareness about biodiversity and slow down the extinction of species around the world. Norway supports the UN's work on protecting biodiversity in various ways, including through the UN's Convention on Biodiversity (CBD) and by reducing deforestation and forest degradation in the Tropics.
Threats to rainforest biodiversity
Since tropical rainforests represent some of the world's most species-rich areas, they are also very vulnerable to extinctions and reduced biodiversity. Any encroachment on such areas will also have a greater impact on biodiversity than in other, less varied areas.
The clearest threat to rainforest biodiversity is logging and deforestation. Clearing forest and replacing it with, for example, grass for cattle rearing, results in a drastic fall in an area's biodiversity. The various types of trees, and all the animals and plants that depend on them, disappear. If the area is home to unique, endemic species, they are at risk of total extinction.
What does biodiversity really mean?
Biodiversity is a measure of the variation we see around us in the natural environment. Some areas, for example a farm in Jæren, Norway, have relatively low biodiversity with various types of livestock, cultivated land, grass and small animals such as insects and earthworms. On the other hand, in tropical rainforests there are many different species, even in small areas. Above the treetops fly birds and insects, and vines and orchids grow on the trees, through which apes, snakes and spiders move. On the forest floor ferns and bushes grow, through which everything from ants to tapir rummage, and between the roots underground grow fungi and mosses, and innumerable small animals burrow their way through the soil.
Rainforests are also home to many species that only exist in specific places, like lemurs on Madagascar, orang-utans in Indonesia, and poison dart frogs in the Amazon, so-called endemic species. When one measures biodiversity one, therefore, finds that tropical rainforests are one of the most species-rich and varied environments on Earth. For example, in a single bush in the Amazon one can find more species of ant than the total one can find on the British Isles.
The mountain gorilla is critically endangered. There are two main populations. One lives in the volcanic mountains of Virunga National Park, which stretches along the border region between the Democratic Republic of the Congo, Rwanda and Uganda. The other lives in Bwindi National Park in Uganda. There are probably only 700 individuals left. Following 20 years of intense, international efforts, this is the only gorilla species' population that is now showing signs of slight growth. The rainforests in Rwanda (CIFOR)
We benefit from the richness and variation of nature
The wealth of species in nature was long taken for granted, but in recent times we have discovered the value of this richness to mankind and society. A species-rich, varied environment is a healthy environment that provides a number of natural services.
- Pollination: One natural service, upon which both nature and farming is totally dependent, is the pollination of sexually mature plants. More than 200,000 insect species (and some birds and bats) perform this job for free, and in many places a complicated interactive and mutually dependent relationship has developed between specific species of plants and animals. If this diversity is threatened, many plants are in danger of facing inadequate or no pollination, which will result in fruit and new plants not being produced.
- Seed distribution: A number of plants (that we utilise) depend on animals to carry and distribute their seeds and here to a mutually dependent relationship has developed. Diversity is yet again the key to ensuring food security. One example of this fantastic diversity is the interaction necessary to disperse the nuts of the Brazil nut tree.
- Fertilisation: Rich and varied life on and below the ground results in the effective decomposition of biological materials and ensures fertile soil, which in turn benefits naturally growing and cultivated plants. If this declines, the plants' productivity can fall, meaning that less food is produced.
- Soil protection: Diverse plant life protects soil and can, for example, prevent the wind blowing the soil away in the event of a drought or landslides due to floods.
- Medicine: Much of medicine is based on natural processes. No less than 50% of the medicines produced in the USA stem from natural products, and the greater the number and the more varied the natural processes one can study, the better the basis for research. Rare and unique animals and plants can provide new insights, and the pharmaceutical industry is convinced that the miracle medicines of the future will be discovered in the rainforests of the world. For example, research into Catharanthus from Madagascar increased the survival chances of children with leukaemia from 20% to 80%. Traditional natural medicine is still practised in large parts of the world, and also relies on a varied source of preparations.
- Technology: Technological ideas and designs are often based on natural forms or processes. For example, George de Mestral invented Velcro after seeing how the burdock plant's seed capsules attach themselves to fur. One cannot predict or prophesy inventions, but by ensuring continued variation in the environment around us, we can ensure that we will have a major source of inspiration in the future as well.
- Resistance to disease: Diseases and parasites are also a part of nature's diversity. In a rich, varied environment, competition, both reciprocal and between them and their host organisms, ensures that no disease will dominate and become a plague or epidemic. On the other hand, in a homogeneous and largely uniform environment, all of the organisms are more alike and it is easy for a few diseases to specialise and spread out of control, as, for example, was the case with the rinderpest virus among cattle. Another example comes from a study in the Amazon, which found that just a 4% increase in deforestation resulted in a 50% increase in malaria cases because of the mosquito's preference for less dense areas of forest.
You could also claim that plants and animals have their own right to live, and that mankind is breaching this right when we drive species to extinction and reduce biological diversity.