hey alex there is no need to be confused.what books do you use for geography?? some books are so bad.
ok vulnerability is the balance of (hydrosphere, atmo, litho and bio) these 4 factors are interdependent, means they can not exist on its own. this interdependence makes ecopsystem vulnerable.
factors influencing the vulnerability of ecosystem are:
LOCATION- climatic variations produced by altitude, latitude and distance dsetermine the nature of terrestrial ecosystem. the more specialised the population of species the more vulnerable it is to changes of environmental conditions. (allways give example)
EXTENT- extent varies with climate( its not easy to estab. extent)
e.great barrier reef ecosystem is about 285sqm in size,(less then 1% of world ocean), but it has great varriety of plant and animal life if climatic change occur the ecosystem could be easily destroyed.
islands is another example, islands have great biological diversity due to isolation, therefore islands are more vulnerable to change, and islands species are more vulnerable to extinction than any other species.
BIODIVERSITY-ecosystems with more species e.g amazon forests are more productive and can be more resilent than simple ecosystems eg polar or desert ecosystems. there is 3 levels of biodiversity- genetic diversity-variations of genetics of individual.
spesie diversity- the veriety of species in different habitats and ecological diversity- the variety of biological communities that interract with each other and non- living environment.
INTEDEPENDENCE----LINKAGES.
interdependence or linkages are closely related to species diversity.
ecosystem with high % of interdependence have higher capacity to absorb change and vice versa.
examples keystone species and umbrella species.
i think thats about it on vulnerability and use BOS main web page it has links go geography notes, and good luck!!!!