Negative Effects of Biodiversity Loss

How does deforestation affect biodiversity? (4)

- Directly reduces number of trees present in an area. - If only a specific type of tree is felled then species diversity is reduced. - Reduces number of animal species in the area (destroys their habitat and source of food) - Animals may migrate to other areas as a result. this reduces biodiversity of other areas.

Areas with low biodiversity (7)

- Few successful number of species - Stressful/extreme enviroment with few ecological niches - Relatively few species live in the habitat - Very specific adaptations to the enviroment - Simple food webs - Enviromental change has a major effect on the ecosystem as a whole - Low biodiversity index (below 0.5)

Areas with high biodiversity (7)

- Large number of successful species - Relatively benign climate with more ecological niches - Presence of many species - Few specific adaptations to enviroment - Complex food web - Change in enviroment has a relatively small effect on the ecosystem as a whole -High biodiversity index (above 0.5)

Factors that increase genetic biodiversity

- Mutations in the DNA of the organism creating more diverse genes. - Interbreeding between different populations creates more diverse individuals.

How do melting of polar ice caps and rising sea levels affect biodiversity?

- Poles of the earth already have low biodiversity. Could lead to exticntion of the few species living there. - Species will migrate towards more favourable conditions. - Rising sea levels reduce habitat diversity be flooding low lying land. -Saltwater flows further up rivers, reducing habitats of freshwater plants and animals.

How do pesticides and herbicides affect biodiversity?

- reduces animal species by killing pest species. By doing this they also kill food sources of other organisms. - Herbicides reduce plant diversity by destroying weeds. Also kills food sources for other animals.

How does disease affect biodiversity?

-Will lower biodiversity initially and will cause populations to go extinct unless they adapt over time.

Ecological arguments to maintain biodiversity.

All organisms are independent on others for their survival. Removal of one species may have a significant effect on others. E.g. a food source or habitat may be lost. Keystone species - A species which are essential to maintain biodiversity. They have a disproportionately large effect on their environment relative to their abundance.

biotic factors

All the living organisms that inhabit an environment.

Economic reasons to maintain biodiversity.

Deforestation causes soil erosion and desertification. This reduces a country's ability to grow crops and feed its people - May lead to economic dependence on other countries. Important to conserve raw materials for industry. Non sustainable sourcing of raw materials will make it economically inviable to continue certain industries. Large scale habitat and biodiversity losses will mean species with economical importance may become extinct before they are even discovered. Undiscovered species may be economically or medically useful. High biodiverse areas promotes tourism.

how will the change in insect life cycles and populations affect biodiversity?

Insects adapt to climate change. They act as pollinators. If their lifecycles change, it could affect the lives of many plant species, leading to extinction.

How do higher temparatures and less rainfall affect biodiversity?

Non drought resistant species of plants will die out. animals that feed on them will die too. drought resistant plants (xerophytes) will become more dominant. animals that used to feed on hydrohphytes will be replaced by animals who feed on xerophytes.

Abiotic Factors

Rainfall pH Temperature Humidity/lack thereof Presence/level of pollution

Factors that decrease genetic biodiversity

Selective breeding (only a few members of a species are selectively bred for their desired characteristics) Captive breeding programmes Natural selection - genes with traits (characteristics) that are less advantageous decline drastically from a population or are lost altogether.

Scientific reasons to maintain biodiversity.

The natural environment provides an outdoor laboratory for developing a better understanding of the natural world. Such research has often yielded results of direct benefit to humans. (medicines etc)

Factors affect biodiversity

deforestation Agriculture Disease Climate change

Why is it advantegeous for a species to have high genetic biodiversity?

likely to have some individuals in the population that carries an advantageous gene which enables them to survive a change of conditions. Without these individuals the species will be extinct.