Question

factor density - independent density - dependent
lava flow
number of predators
spread of disease
especially cold winter
toxic chemical spill into a stream
another species competing for the same resources
diverting a river for irrigation
fungus that attacks elm trees
analyze why populations are limited in their spatial distribution.

Explanation:

Density - independent factors affect populations regardless of density (e.g., lava flow, cold winter). Density - dependent factors are influenced by population density (e.g., number of predators, spread of disease among a species). Populations are limited in spatial distribution due to both types of factors. Density - independent factors can directly destroy habitats or make areas uninhabitable (like a toxic chemical spill). Density - dependent factors such as competition for resources or spread of disease can limit where a population can thrive based on how many individuals are in an area.

Answer:

Populations are limited in spatial distribution by both density - independent factors (physical and environmental changes) and density - dependent factors (inter - species and intra - species interactions).