Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
Concept
Population model
Résumé
A population model is a type of mathematical model that is applied to the study of population dynamics.
Models allow a better understanding of how complex interactions and processes work. Modeling of dynamic interactions in nature can provide a manageable way of understanding how numbers change over time or in relation to each other. Many patterns can be noticed by using population modeling as a tool.
Ecological population modeling is concerned with the changes in parameters such as population size and age distribution within a population. This might be due to interactions with the environment, individuals of their own species, or other species.
Population models are used to determine maximum harvest for agriculturists, to understand the dynamics of biological invasions, and for environmental conservation. Population models are also used to understand the spread of parasites, viruses, and disease.
Another way populations models are useful are when species become endangered. Population models can track the fragile species and work and curb the decline.
Late 18th-century biologists began to develop techniques in population modeling in order to understand the dynamics of growing and shrinking of all populations of living organisms. Thomas Malthus was one of the first to note that populations grew with a geometric pattern while contemplating the fate of humankind. One of the most basic and milestone models of population growth was the logistic model of population growth formulated by Pierre François Verhulst in 1838. The logistic model takes the shape of a sigmoid curve and describes the growth of a population as exponential, followed by a decrease in growth, and bound by a carrying capacity due to environmental pressures.
Population modeling became of particular interest to biologists in the 20th century as pressure on limited means of sustenance due to increasing human populations in parts of Europe were noticed by biologist like Raymond Pearl. In 1921 Pearl invited physicist Alfred J. Lotka to assist him in his lab.
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.
Cours associés (11)
PHYS-302: Biophysics : physics of biological systems
Understand and use the results and methods of population genetics, population dynamics, network theory, and reaction network dynamics to analyze and predict the behavior of living systems
AR-507: Urban demography
This course introduces theoretical developments and empirical evidence on city population change worldwide, as well as on its interactions with sustainable development.
PHYS-642: Statistical physics for optimization & learning
This course covers the statistical physics approach to computer science problems, with an emphasis on heuristic & rigorous mathematical technics, ranging from graph theory and constraint satisfaction
Publications associées (54)
Personnes associées (12)
Concepts associés (3)
Population dynamics of fisheries
A fishery is an area with an associated fish or aquatic population which is harvested for its commercial or recreational value. Fisheries can be wild or farmed. Population dynamics describes the ways in which a given population grows and shrinks over time, as controlled by birth, death, and migration. It is the basis for understanding changing fishery patterns and issues such as habitat destruction, predation and optimal harvesting rates. The population dynamics of fisheries is used by fisheries scientists to determine sustainable yields.
Démécologie
thumb|350px|Groupes familiaux d'éléphants, au sein d'une population régionale thumb|350px|Un groupe de « populations » constitue une métapopulation. Les populations d'animaux, plantes, champignons, microbes... contribuent au fonctionnement des écosystèmes, qui eux-mêmes forment des biomes et la biosphère ou symbiosphère (expression de Joël de Rosnay est le niveau planétaire d'intégration de toutes les échelles du Vivant (du gène à la somme des biomes (sans laquelle l'oxygène et donc la couche d'ozone n'existeraient pas) ; Le gène est représenté à part, car non vivant en tant que tel, mais support d'information et base du vivant.
Dynamique des populations
La dynamique des populations est une branche de l'écologie qui s’intéresse à la fluctuation dans le temps du nombre d'individus au sein d'une population d’êtres vivants. Elle a également pour but de comprendre les influences environnementales sur les effectifs des populations. La structuration de la population par âge, poids, l'environnement, la biologie des groupes, et les processus qui influent sur ces changements font également partie de son champ d'étude.