Before looking deeper into the loss of biodiversity and its impacts, let us first understand what biodiversity really means.
Biodiversity refers to the variety and variability of life on Earth. It includes the number of plants, animals, and microorganisms from the Earth’s vastly different ecosystems such as coral reefs, grasslands, tundra, polar ice caps, deserts and rainforests.
According to the United Nations Environment Programme (UNEP), variation in biodiversity is typically measured at three levels namely the genetic, the species, and the ecosystem level. Biodiversity is not evenly distributed on the planet and is richest in the tropics. The tropical forest ecosystems contain about 90 percent of the world’s species but cover less than 10 percent of Earth’s surface.
Marine biodiversity tends to be highest in areas with high sea surface temperature. Some examples include the mid-latitudinal band in all oceans and the areas along coasts in the Western Pacific. Biodiversity generally tends to cluster in hotspots and continuously increasing with time, but possibly to slow down in the future.
Biodiversity is indeed, very important to the well-being of Planet Earth. The importance of healthy ecosystems and rich biodiversity can be underscored by the following points.
Loss of biodiversity refers to the extinction of human, plant or animal species worldwide. It also includes the decrease in the number of a species in a certain habitat. The environmental degradation that leads to the loss can be either reversible or effectively permanent. Though, it has been noticed that global extinction so far is irreversible.
To realise the gravity of the problem, let us have a look on the rate of biodiversity loss. It is estimated that the current rate of biodiversity loss is 100 to 1000 times higher than the naturally occurring extinction rate and is still expected to grow in the future. This loss of biodiversity has a number of impacts on both human and animal life.
Unfortunately, human activities greatly contribute to the loss of biodiversity. Natural resources like land and water are indiscriminately exploited by humans. According to the Convention of Biological Diversity, direct and indirect human activities have a detrimental effect on biodiversity. Direct human drivers include changes in local land use, species introductions or removals, harvesting, air and water pollution, and climate change. Indirect human drivers include demographic, economic, technological, and cultural and religious factors.
The growth in population is a major factor in fuelling the demand for natural resources. It also leads to greater waste generation, which is also a major cause of pollution. Human needs and the increased use of technology to meet them play a major role in climate change, which continues to be a big threat to biodiversity.
Increased atmospheric concentration of carbon dioxide causes climate change. Due to large-scale cutting of trees every year, carbon dioxide cannot be absorbed and its concentration in the air increases. Climate change has resulted in increased land and ocean temperature, change in precipitation and rise in the sea level. The change in climate has an inimical impact on species.
The major factors that contribute to the loss of biodiversity include the following:
The natural habitat of animals is destroyed by man for the purpose of settlement, agriculture, mining, industries, construction of highways, and so on.
As a result of this, the species must either adapt to the changes in the environment or move to other places. If not, they become target to predation, starvation, disease and eventually die.
Hunting of wild animals is done for the commercial utilisation of their products. These include hides and skin, fur, meat, tusk, cosmetics, perfumes, pharmaceuticals, and decoration purposes. In recent years, 95% of the black rhino population in Africa has been exterminated by poachers for their horn.
In addition to this, over one-third of Africa’s elephants have been killed in the last decade to collect 3,000 tonnes of ivory. Though the formulation of International laws and Indian regulations has reduced hunting in a large amount but poaching still continues to be a threat to biodiversity.
Exploitation of medicinally important plants results in their disappearance from their natural habitat. Examples of the plants which are ruthlessly collected for laboratory and other works are the pitcher plant, Nepenthes khasiana, Drosera sp., Psilotum sp. Isoetes sp etc.
An “unnatural separation of expansive tracts of habitats into spatially segregated fragments” that is too limited to maintain their different species for the future, is known as habitat fragmentation. The landmass is broken into smaller units which eventually lead to the extinction of species.
Animals and plants are collected for zoos and biological laboratories. This is majorly done for research in science and medicine. Primates such as monkeys and chimpanzees are sacrificed for research because of their anatomical, genetic and physiological similarities to human beings.
A species which is not a natural inhabitant of the locality but is deliberately or accidentally introduced into the system is termed as an exotic species. Due to the introduction of exotic species, native species have to compete for food and space.
Pollution makes survival difficult for the species as it alters their natural habitat. Water pollution is injurious to the biotic components of coastal ecosystems. Toxic wastes entering the water bodies disturb the food chain. In addition, materials like insecticides, pesticides, sulphur and nitrogen oxides, and acid rain also adversely affect the plant and animal species.
Generally, non-target species that are a component of balanced ecosystem may also get killed in the predator and pest control measures.
Floods, draught, forest fires, earth-quakes and other natural calamities sometimes take a heavy toll of plant and animal life. These trap a large number of animals while frittering away soil nutrients.
Other Ecological Factors that contribute to the loss of biodiversity include:
(a) Distribution range – The threat of extinction increases as the size of distribution range becomes smaller.
(b) Degree of specialization – specialized organisms are more vulnerable to extinction as compared to the non-specialized ones.
(c) Position of the organism in the food chain – the higher the position of the organism in the food chain, the more susceptible it is.
The negative effects of the loss in biodiversity from a healthy stable state include dramatic influence on the food web and chain. Even reductions in only one species can adversely affect the entire food chain which further leads to an overall reduction in biodiversity. Reduced biodiversity leads to immediate danger for food security by reducing ecosystem services and for humankind also.
The effects of extinction of animal and plant species are widespread. Here are six significant problems caused by loss of biodiversity:
The economic cost of biodiversity around the world tops the list. We will have to pay for costs of pollination, irrigation, soil reclamation and other functions if nature is unable to take care of them. The estimated value of global biodiversity is in the trillions. Deforestation costs around $2-5 trillion annually worldwide.
The introduction of new species is happening on farms, too, where natives are pushed out because of imported foreign breeds of cattle. The effect of this is the narrowing of the world’s livestock population. They are also becoming more susceptible to disease, drought, and changes in climate.
The loss of biodiversity has two major effects on human health and the spread of disease. Firstly, it increases the count of animals carrying disease in local populations. As habitats reduce in size, these animals become common, winning out the species that do not generally transmit disease.
Indeed, unseasonable weather and extreme weather is a huge problem which leads to destruction and displacement. Research has shown that loss of species causes more unpredictable weather.
Biodiversity is essential for maintaining livelihoods. Taking an example, when ocean ecosystems collapse, entire communities built on the plenty they provide lose their means of employment as well. The cause can be pollution, overfishing, or a combination of these. Humans are always affected by the downfall of the ecosystem surrounding them.
The worth of nature to humanity is far beyond the utility of it. The physical deflation of nature certainly does affect humans. People always tend to find solace in nature. It also provides a recreation spots for us to take a break from our busy lives. But loss of biodiversity threatens to take away the value that man finds in nature.
(How to Prevent Loss of Biodiversity/How to Conserve Biodiversity)
The reduction in land and soil degradation and formation of regulated protected areas and national parks, in addition, are among important solutions to the loss of biodiversity. However, these have limitations in tackling the biodiversity crisis to the full extent.
What is required is to place greater emphasis on sustainable practices in agriculture, which is the most significant cause of biodiversity loss. Thousands of traditional crops have become threatened species as they have been discarded for food production, a concept called mono production.
An alternative approach that can be introduced here is “agro-ecology” or “eco-farming”. It seeks higher yields achieved through intense cultivation on small farms. It is a low input model that requires skills in processes like soil regeneration, nitrogen fixation and natural pest control. Reconciliation of these changes in agriculture is critical for both food security and biodiversity.
Along with the proposed changes in agriculture, there are other solutions to the biodiversity loss too. Some of them are simple changes we need to bring in our daily lives.
Conclusion
Biodiversity or the variety of plants and animals in the environment plays an important role in maintaining balance in the ecosystem. The loss of biodiversity gives rise to a lot of problems like decreased food security, disruptions in the food chain, climate change, loss of livelihoods etc. This has a huge impact on humans as there will longer be food to eat, prices of commodities will rise and the beautiful sight of nature will be lost.
Moreover, ecosystem balance gets disturbed. The problem is indeed a very grave one, and it’s time humans realize what impact their actions have on the environment. Proposed solutions like alternate approaches in agriculture, consuming less and generating lesser waste should be adopted. Only then the biodiversity loss rates can be reduced and humans can live in harmony with Mother Earth.