השוואת שיטות

	ניתוח חוסן אוכלוסייתי	מודל הקרנה אינטגרלי
תחום	אקולוגיה	אקולוגיה
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1981	2000
הוגה השיטה	Mark Shaffer	Stephen Ellner and Mark Rees
סוג	extinction risk assessment	size-structured population projection
מקור מכונן	Shaffer, M. L. (1981). Minimum population sizes for species conservation. BioScience, 31(2), 131-134.	Easterling, M. R., Ellner, S. P., & Dixon, P. M. (2000). Size-specific sensitivity: applying a new structured population model. Ecology, 81(3), 694-708.
כינויים	PVA, extinction risk, minimum viable population, MVP	IPM, continuous size structure, kernel model, size-structured population
קשורות	4	4
תקציר	Population Viability Analysis (PVA), introduced by Shaffer (1981), estimates the probability that a population will persist over a given time period under specified conditions. PVA combines demographic models (Leslie matrices, IPMs) with stochastic simulation to project population trajectories, quantifying extinction risk. This allows conservation planners to assess whether a population will likely persist, evaluate management scenarios, and estimate the minimum viable population (MVP) size for long-term persistence. PVA is a decision-support tool, not a precise predictor.	Integral projection models (IPMs) are a class of structured population models that use continuous traits (size, age, height) to describe population dynamics. Introduced by Easterling and colleagues (2000) and developed extensively by Ellner, Rees, and collaborators, IPMs overcome limitations of age- or stage-structured models by treating individual traits as continuous. They use integration to project populations forward in time, making them particularly suitable for organisms with continuous size distributions or flexible developmental pathways. IPMs enable estimation of population growth rate (λ), sensitivity analysis, and projection under changing environmental conditions.