Human impact on biodiversity and ecosystem loss
Abstract Biodiversity and ecosystem are crucial issues that have an impact to the human well-being now and in the future. Biodiversity depends on many factors but the most influentive is the habitat loss which influences the biodiversity worldwide. Humans converts native areas into agriculture and industrial areas without realising how much impact it has now and will have in the future. Habitat loss is connected with fragmentation which influence the increasing amount of extinction. The specific climate is essential to be maintained for some species.
If it is changed some species may not be able adjust to new conditioins such as extreme weather conditions like drought or flooding and long term changes in water and air temperature. It causing species to die out. It is a huge threat for the ecosystem because every specie is dependet on another one. Another global threat are alien species that become invasive and suppress the native habitants. In addition, species dependent on the suppressed ones will have to adobt or they will become extint.
Out of the 44, 838 species living on the earth, 905 are already extinct and 16, 928 are listed to be endangered and possibly become extinct. Aaet-asean. Retrieved from: http://www. aaet-asean. org/upload/Ear%20Choung%20Chhay-%20Essay. pdf Considering that many species are not officially assessed on the list, there are probably many more species that does not exist any more. Most of the extinct species died out due to the human activity. The most serious causes of extinction are habitat loss, alien invasive species and the global climate change.
In this essay, I will discuss the human factors that are causing the extenction of the species. Habitat loss and fragmentation are the largest cause of biodiversity and ecosystem loss. Eco-question. (2010) Retrieved from http://www. eco-question. com/what-are-the-main-causes-of-biodiversity-loss. Humans change wild areas into industrial regions including power stations, cities, dams and irrigation and into areas used for forestry, urban development and agriculture. They convert the area inhabited by the native species into the area used just for human profit.
These changes the specific ecosystem including climate, type of plants, food sources and temperature conditions. Some species are able to adjust to different conditions but more specialized ones may not be able to adapt and can become extinct as a result of human activity. Commercial forestry causes cutting forests which are shelter for some species and it also causes the spread of the particular tree species. People grow the trees with high quality wood and high speed of growth and the diversity is not maintained. Learner. Retrieved from: http://www. learner. org/courses/envsci/unit/text.
php? unit=9&secNum=7. Dams flood huge areas above them and cause to reduce the amount of a paticular specie. It also changes the river pattern and it increase the river temperature causing more carbon dioxide absorbed. Also the fish may not be able to swimm upstream due to the change in the temperature. Farmers grow particular crops that require special nutriens which are taken out of the soil and causing the soil exhaustion. Fertilizers and pesticides are used and it changes the native composition of the ground and causing the difficult survival conditions for some species.
Also ranching has an impact on the habitat loss such as overgrazing and reducing space where the native species can grow and live. The urban areas are covered with pavements and concrete that increases the surface run-off and it therefore reduce the amount of water absorbed redulting in smaller amount of groundwater stored. Water is also polluted with junk from the streets and greenhouse gases from the traffic transporters and industrial areas. The Millennium Ecosystem Assessment has proved that one-quarter of Earth’s terrestrial area has been converted into cultivated land.
Land is becoming less suitable for the native population and this leads to the extenction of the species. Habitant fragmentation is a process caused be road-building and spreading large sectors of land into fragments. Species are becoming isolated, and it is therefore harder to survive. It reduces biodiversity by slitting species into small groups which are more vulnerable because isolated individuals are less able to defent demselves or find a partner and reproduse. In the small fragments may not be enough space for all the species and crowding or competetions can occur.
Reduce of access to water resources can take a place and more contact between humans and animals can happen. If the animals are causing troubles to humans they are removed. Fragmentation also causes building up ecosystems that are more vulnerable to invasive species. For example when a pavement is built next to the meadow, the edges are less suitable for species that live in shalter areas. Only few species can survive in such conditions and invasive species have therefore more space where they can spread. Moreover, the amount of extinction can increase because the small fragments are suitable for less species.
Many animals need different areas to survive. For example when a specie need an access to water, meadow for grazing and a forest as a shelter and is placed on a land fragment where one of these is not, he will not be able to survive. Learner. Retrieved from: http://www. learner. org/courses/envsci/unit/text. php? unit=9&secNum=7. The global climate change is the first factor caused by people that affects biodiversity loss. The biodiversity loss in oceans in the highest lost today and much higher than it was before.
It is due to the changing conditions in the ocean such as higher water temperature, rise of sea levels and increasing level of the greenhouse gases. Many species are not able to adapt to changes of water temperature and therefore it causes the extention of these species. Also the increasing amount of greenhouse gases released into the atmosphere by transport facilities and industrial areas has an impact to the biodiversity. These gases store the heat from the earth and then cause this heat to warm the whole planet including the ocean. The glaciers and ice are melted and the water level in the ocean increase.
The species that need the very specific climate conditions in areas that are flooded by the water from the ocean are forced to move into different areas with unlike climate conditions. Some species are able to adapt but some of them are not and there will be the risk of extention. The extention of these species will greatly affect other marine life as well. The ecosystem is interdependet and therefore the speacies thet depend on the extinct ones will struggle. They will have to adapt but if they are not able to adapt, they will die out. The
increase of water temperature in the oceans also causes the increase of amount of carbon dioxide absorbed. The marine biodiversity will suffer by this because it is causing the increase of acidity in the water. Irrawaddy dolphin living in coastal areas is for example dependent on the flow fresh of water. Any change in temperature or acidity affect its chances to long-term survival. Apart of the ocean, the global warming has an impact on terrestrial biodiversity as well. Some species require the specific area as well as very specific area and they are endangered by any change (e. g.
bicknell’s thrush which is a type of bird). The change in temperature threatens the bird’s breeding habitants. News. discovery. com. (2009). Retrieved from: http://news. discovery. com/animals/list-of-animals-threatened-by-climate-change. htm Another factor are alien species, both plant and animal. The plant invasion results in reduced light, nutrient, moisture and space available to native species. It the invasivee specie has the right conditions in the invaded area, it survive, spread and reproduce. If it is more resistant, it take the place where was originally a native species and suppress it.
Invasive plant species have the common characteristics which make difficult to control it’s spread. It includes higher rates of reproduction, in fact one plant can produce up to three million seeds. Because it is an invasive plant, it does not have many natural predators and it therefore distructs the balance in the native ecosystem. Also these species are able to survive in the most of climate and enviromental conditions, which results in even higher spread. Once the alien species is spread, it is almost impossible to get rid of it. This is a huge issue in Canada, where the Purple loosestrife is spread.
It is an European invader which was brought to Canada in1800s and it invaded wetlands. It is very resistant and it can suppress native plants. The animals such as fish and birds which are dependent on the suppressed plants will loose it’s source of nutrition and it can result in further extincion. This plant is very reproductive, if fact, a signle plant can produse over 300, 000 seeds. It is also very adaptible and it can grow in irrigation canals, ditches and standing water. In some locations it has already started to invade dry habitants such as cropland and pastures. Invading species,
Retrieved from: http://www. invadingspecies. com/invaders/plants-terrestrial/purple-loosestrife/ Also the animal invadors are huge threat to biodiversity and ecosystem loss. It has the same convenients as the plant species. It does not have any native predators and it is easily adaptable to survive in different conditions. The alien invasive species often become predators and represent a threat to the native animals. For example, one of the worst invasive animal is the European common rabbit. It is native to live in north Africa and southern Europe but the rabbit has a tendency to overproduce.
This has lead to the spread of the rabbits to every continent except Asia and Antarctica. Probably the most famous and serious expansion occured in Australia in 1859. An English farmer brought only 24 rabbits because he did not expect that this small number could result in any big ecosystem change. Howevere, in ten years, the rabbits suppressed the local rabbits and spread abnormally. Two million of the rabbits could be shot annually without any imporant impact on the rabbit population. After hundred years, the rabbit caused serious problems such as dround erosion caused by overgrazing and surroving.
It has also caused the most serious loss of Australia biodiversity in history. News discovery. (2009). Retrieved from: http://news. discovery. com/animals/list-of-animals-threatened-by-climate-change. htm However, humans also contribute to maintaining the biodiversity. We are finding alternatives in land-using and we are trying to change the habitat destruction. For example humans are trying not to grow just one specie but to grow the native and diverse plants. Humans also try to reduce the amount of over-spread species and maintaining the original species in the ecosystem.
Careful planning of land-use and consideration in affecting of biodiversity also helps to maintain the biodiversity. Natural parks and zoos grow and reproduce huge range of endangered animals and releasing into the wild helps to renew and maintain the original composition. Natural parks, zoos and reservatioins can be the only places with maintained biodiversity and humans are therefore trying to utilise the forests used for growing wood as a new home for endangered species. If woods are cut gradually, there is always a place where animals and plants can grow and reproduce.
Many ecological ways to prevent the amount of global warming are also developing. In the future, there will be ways how to travel and live without increasing the levels of carbon dioxide and therefore without causing global climate change. Considering the major causes of biodiversity loss, I came to the conclusion that humans have a very significant impact on loss of biodiversity. We should try reduce the habitat loss through carefull planning and considering the use of land and try to prevent any significant fragmentation.
Through reducing increase of carbon dioxide released to the atmosphere we can reduce the global climate change and therefore the amount of exctinction. Finally, we have to beware of any invasive alien species through removing any, even very small number of non-native species. However, humans are not only causing the biodiversity loss but we are also contributing to maintain of endagered species through founding of natural parks, zoos and reservations and trying to avoid any significant losses in biodiversity by poor planning.