For many years, the evaluation of water quality of north carolina streams was defined in chemical terms, ignoring the biological component. more frequently now, the bioindicator is used to evaluate stream quality. what is the biotic index? a)the bioindicator is a scale based on algae levels, used to measure water quality in streams. b)the bioindicator is a scale based on fungus levels, used to measure water quality in streams. c)the bioindicator is a scale based on coliform bacteria levels, used to measure water quality in streams. d)the bioindicator is a scale based on the tolerance value of macro-invertebrates in an environment, used to measure water quality in streams.

answer: decrease

a limiting factor is the one which decrease the abundance, distribution and causes extinction of the population of species in a ecosystem. here, predators including hawks, owls and snakes are the limiting factor for the population of mexican free tailed bat.   although bats are nocturnal animals as they forge for food at night these predators also may remain active during night which can decrease the population of the mexican free-tailed bats. also, these bats eat only one type of insects that are moths. the food can also be a limiting factor as all 400 members are dependent upon same type of food needs that are moths. the decrease in the moth population can cause decrease in population size of the mexican free-tailed bats.

therefore, the scenarios will most likely to decrease the population size of the mexican free-tailed bats.  

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint