The Influence Of Landscape Pattern And Scale On The Landscape Genetics Simulation Under The Size Of Effective Population

Landscape genetics is a novel field of research that integrates population genetics, landscape ecology and spatial statistics, gradually showing its potential in ecological protection. The core of landscape genetics is to connect the spatial pattern of heritable variation with the extremely random space-time course so that the result can be both historic and realistic. Landscape genetics simulation technique, a new practical research technique that combines landscape genetics and computer simulation, can be used in this field to integrate individual and environmental randomness. The key function of this technique is to combine individual process with landscape features and reveal the influence it has on individual occupancy, population size, and gene flow through computer simulation, determining its special genetic structure to understand the causal relationship between landscape features and gene flow. The influence factors of the landscape factors in landscape genetics simulation can be classified into two kinds: landscape type factor and landscape size factor. The former includes habitat area and non-habitat area, non-habitat resistance value, the fragmentation degree of the landscape and so on. The later includes the size of the landscape map scope, the designation of landscape map pixel size and so on. The variables of population in landscape genetics simulation mainly include the select range of population capacity, number of subpopulation, specific value of each subpopulation capacity and so on. All these factors make up the whole system of variables in landscape genetics simulation experiment. This essay explores the influence every landscape genetic factors have on landscape genetics simulation through simulation modeling. The gradient variable test finds that when ratio between non-habitat area and habitat area is beyond certain threshold value, the trend of reducing genetic variation of population increases. The setting of resistance value also shows scale effect: when it is beyond certain threshold value, the trend of reducing genetic variation of population increases. However, the influences fragmentation degree of landscape has on genetic variation have no significant trend. The gradient test of landscape size shows selection of size scale will influence the simulation result. As for population variables, the gradient test shows variables except population capacity has no significant influence on genetic variation. This experiment provides valid reference in predicting genetic differentiation through landscape index in landscape genetic simulation, and illustrates that correct selection of landscape index can guarantee the validity of the prediction.