Demographic and environmental stochasticity - Concepts and definitions

被引:168
作者
Engen, S [1 ]
Bakke, O [1 ]
Islam, A [1 ]
机构
[1] Norwegian Univ Sci & Technol, Dept Math Sci, N-7034 Trondheim, Norway
关键词
birth and death processes; branching processes; demographic stochasticity; diffusion approximation; environmental stochasticity; population models;
D O I
10.2307/2533838
中图分类号
Q [生物科学];
学科分类号
07 ; 0710 ; 09 ;
摘要
General definitions of demographic and environmental variances as well as demographic covariance are given from first principles. The sum of the environmental variance and the demographic covariance is the covariance between two individuals' contributions to the population growth within a year and corresponds to the coefficient of x(2) in the expression for the variance of the change in population size. Hence, this coefficient may actually be negative. The demographic variance is the variance among individuals. It is shown that the definitions are consistent with use of these terms in models with additive effects and in diffusion approximations to population processes. The connection to classical birth and death processes, in which the environmental variance and demographic covariance is always zero, is discussed. The concepts are illustrated by some stochastic simulations.
引用
收藏
页码:840 / 846
页数:7
相关论文
共 13 条
[1]   BRANCHING PROCESSES WITH RANDOM ENVIRONMENTS .1. EXTINCTION PROBABILITIES [J].
ATHREYA, KB ;
KARLIN, S .
ANNALS OF MATHEMATICAL STATISTICS, 1971, 42 (05) :1499-+
[2]   HARVESTING NATURAL-POPULATIONS IN A RANDOMLY FLUCTUATING ENVIRONMENT [J].
BEDDINGTON, JR ;
MAY, RM .
SCIENCE, 1977, 197 (4302) :463-465
[3]   ESTIMATION OF GROWTH AND EXTINCTION PARAMETERS FOR ENDANGERED SPECIES [J].
DENNIS, B ;
MUNHOLLAND, PL ;
SCOTT, JM .
ECOLOGICAL MONOGRAPHS, 1991, 61 (02) :115-143
[4]   Population dynamic models generating the lognormal species abundance distribution [J].
Engen, S ;
Lande, R .
MATHEMATICAL BIOSCIENCES, 1996, 132 (02) :169-183
[5]  
Goodman D., 1987, P11, DOI 10.1017/CBO9780511623400.003
[6]   CONFIDENCE-INTERVALS FOR DEMOGRAPHIC PROJECTIONS BASED ON PRODUCTS OF RANDOM MATRICES [J].
HEYDE, CC ;
COHEN, JE .
THEORETICAL POPULATION BIOLOGY, 1985, 27 (02) :120-153
[7]   EXTINCTION AND EXPONENTIAL-GROWTH IN RANDOM ENVIRONMENTS [J].
KEIDING, N .
THEORETICAL POPULATION BIOLOGY, 1975, 8 (01) :49-63
[8]   OPTIMAL HARVESTING OF FLUCTUATING POPULATIONS WITH A RISK OF EXTINCTION [J].
LANDE, R ;
ENGEN, S ;
SAETHER, BE .
AMERICAN NATURALIST, 1995, 145 (05) :728-745
[10]  
LEIGH EG, 1981, J THEOR BIOL, V90, P213