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1. What is biodiversity?
Biological diversity is the variety of species of living beings of an ecosystem. In ecosystems which are more biodiverse, like tropical forests, a great variety of plants, microorganisms and animals live; in ecosystems less biodiverse, like deserts, there are less variety of living beings.
Image Diversity: variety of life on earth
2. How does biological diversity relate to the characteristics of the abiotic factors of an ecosystem?
The availability of abiotic factors like light, moisture, mineral salts, heat and carbon dioxide, more or less conditions the biodiversity of an ecosystem. Photosynthesis depends on water and light, and plants also need mineral salts, carbon dioxide and adequate temperature for their cells to work. In environments where these factors are not restrictive the synthesis of organic material (by photosynthesis) is at a maximum, plants and algae can reproduce easier, the population of these beings increase, potential ecological niches multiply and new species emerge. The large mass of producers makes viable the appearing of a diversity of consumers of several orders. In environments with restrictive abiotic factors, like deserts, the producers exist in small numbers and less diversity, a feature that thus extends to consumers and conditions fewer ecological niches to be explored.
3. How does the vegetal stratification of an ecosystem influence the biological diversity?
The vegetal stratification of an ecosystem, like the strata of the Amazon Rainforest, creates vertical layers with peculiar abiotic and biotic factors, dividing the ecosystem into several different environments. Therefore in the superior layer near the crowns of big trees the exposition to light, rain and wind is greater but moisture is lower compared to the inferior layers. As one goes down the strata the penetration of light diminishes and moisture increases. Regarding the biotic factors, communities of each stratum present ing differcomposition and features, food habits, reproduction strategies, etc. Such variations in the abiotic and biotic factors make the selective pressure upon living beings to be also diversified, there are more ecological niches to be explored and more varied beings emerge during the evolutionary process.
4. Despite having a great biodiversity why is the Amazon Rainforest under risk of desertification?
The natural soil of the Amazon Rainforest is not very fertile but it is enriched by the vegetal covering made of leaves and branches that fall from the trees. Deforestation reduces this enrichment. In deforestation zones the rain falls directly on the ground causing erosion, “washing” large areas (leaching) and contributing to make the soil even less fertile. Besides that, the deforestation disallows the recycling of essential nutrients for plants, like nitrogen. In this manner those regions and their neighboring regions undergo desertification.
Image Diversity: Amazon Rainforest
5. How can a great biological diversity protect an ecosystem from environmental damage? Why are less biodiverse ecosystems at risk of suffering deep biological harm if submitted to even small changes?
In ecosystems with more biodiversity the food webs and ecological interactions among living beings are more complex and diverse. In these ecosystems environmental changes can be more easily compensated by the multiplicity of available resources, foods and survival options.
In ecosystems with less biodiversity the individuals are more dependent on some beings that serve them as food and they interact with a small number of different species. In these ecosystems generally abiotic factors are restrictive and the species are more specialized to such conditions and more sensitive to environmental changes. So even small environmental harm can cause big disturbances in the equilibrium of the ecosystem.
6. Is monoculture a system that contributes to great biological diversity of an ecosystem?
Monoculture means that in a large area a single crop (only one species of plant) is cultivated. Therefore monoculture does not contribute to the formation of a community with great variety of species in the area. Since there is only a single type of producer the types of consumers that can live in the area are also restricted.
7. What are some economic applications that can be generated by very biodiverse ecosystems?
Very biodiverse areas present enormous economic potential. They can be a source of raw material for the research and production of medicines, cosmetics, chemical products and food. They are depositories of genetic wealth that can be explored by biotechnology. They are sources of species for agriculture. They can also be explored by 'ecological tourism'.
8. What are the main causes of the loss of biological diversity nowadays?
The biggest dangers to biological diversity today are the action of humans. The main of them is the destruction of habitats caused by the growth of the cities, deforestation, pollution and fires. The second is the invasion of ecosystems by nonnative species introduced by humans; these species change the equilibrium of ecosystems causing harm. Other big dangers are predatory hunting and fishing and global warming.
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