Populations go down for a variety of reasons, broadly classifiable as increasing death rates (war, disease, famine, natural disaster such as earthquake or tsunami) or decreasing birth rates (which happens generally as a result of higher standards of living - wealthier people want fewer children).
Second opinion, government could but they won't and common sense if they don't Mother Nature will take care of it at some point. Only problem is she may do too good of a job. We had our chance and blew it. 7 billion now, 9 billion by 2040 which means 12 billion by 2100. The planet cannot support that many and will take care of the problem. No one in power wants to admit to the facts and make the hard choices now that could maybe give us a chance. People just keep breeding like rats and we will all pay the price.
it is an environmental factor that causes a population to decrease.
It is called a limiting factor.
More predators so the population would decrease :(
abiotic resource. Examples include environmental factors like drought, temperature extremes, or pollution that can directly affect the survival or reproduction of a population, leading to a decrease in population size.
The general term for an environmental factor that causes a population to decrease is a limiting factor. Some examples are emigration and mortality, a lack of resources, natural disasters happen which makes people scared to to live there so the people flee, and habitat loss.
The environmental factor is excessive sun exposure.
Factors that decrease population growth can be defined as environmental stress including limitations in food, predation, and other density-dependant factors
Decrease
Pollution was a small factor but the largest factor is the spread of the Asian Carp which feed on algae and surface insects. This causes a disruption in the entire river ecosystem all the way to the largemouth bass causing a decrease in available food and therefore a decrease in population.
limiting factor
It increases the odds of mutation.
the climate