But the amount of new cultivable land that can be brought under production is limited. In many nations, the need to feed a growing population is spurring an intensification of agriculture—finding ways to grow higher yields of food, fuel, and fiber from a given amount of land, water, and labor. Population Ecology. A population is a group of interbreeding organisms found in the same place at the same time. Population ecology studies the dynamics of populations and how populations interact with the environment. There are a number of characteristics of populations that help ecologist and other scientists to monitor and manage wild ... A population is a group of organisms that are all the same species. That's it. You're done. A group of ducks would not be a population if there were mallard and wood ducks combined. Scientists would say that there are two populations existing in the same area. Population biologists study groups in a specific area. Population Ecology: Fecundity ... over its lifetime and represents one of the major cornerstones of theoretical and applied population biology. Fertility, a related concept, is defined as the ... In population ecology, density-dependent processes occur when population growth rates are regulated by the density of a population. Most density-dependent factors, which are biological in nature (biotic), include predation, inter- and intraspecific competition, accumulation of waste, and diseases such as those caused by parasites.