Abiotic factors are non-living variables. Biotic factors are the interactions between organisms. Both affect diversity and distribution. Sampling helps us to estimate numbers of organisms in an area.
bioticLiving elements of an ecosystem, such as plants and animals. factors are interactions associated with living organisms. They can also influence the distribution of organisms in an ecosystem.
Examples of biotic factors are:
competition for environmental resources
grazing - too little leads to dominant plants outcompeting other species, too much reduces species numbers overall. Both decrease biodiversity
predation - a reduction in predators can lead to an increase in prey. High numbers of prey can lead to overgrazing, which can reduce biodiversity