Spatial genetic structure in 21 populations of butternut, a temperate forest tree (Juglans cinerea L.), is correlated to spatial arrangement, habitat, and land-use history

• Published in: Forest ecology and management Vol. 314; pp. 50 - 58
• Main Authors: Hoban, Sean M., McCleary, Tim S., Schlarbaum, Scott E., Romero-Severson, Jeanne
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15-02-2014; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Dispersal; Forestry; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; Isolation-by-distance; Recruitment; Riparian; Sp statistic; Spatial genetics; Synecology; Terrestrial ecosystems; PS; F1O; Fij; Sp statistic; F1; Recruitment; Dpos; RelO; FIS; Isolation-by-distance; Riparian; Dispersal; PJ; Sp; Spatial genetics; Geographical isolation; Juglans cinerea; History; Temperate zone; Dicotyledones; Angiospermae; Genetics; Population; Habitat; Fruit tree; Temperate forests; Spatial organization; Genetic structure; Forest ecology; Forest tree; Woody plant; Statistics; Spatial structure; Dispersion; Land use; Juglandaceae; Fruit crop; Spermatophyta
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2013.11.001

•We investigated spatial genetic structure (SGS) in 21 populations of butternut.•We tested the effect of local ecological conditions on several SGS metrics.•Local conditions (habitat, aggregation and site history) correlated to SGS.•Results suggest that local ecological conditions may contribute to SGS variation.•Analyzing a small number of populations is likely insufficient to capture SGS.
It is well known that spatial genetic structure (SGS), a phenomenon that occurs to some degree in most plants, is influenced by species’ characteristics such as dispersal biology. However, local conditions (e.g., spatial, environmental, demographic) may also contribute to SGS, but the influence of local factors is rarely quantified. To test the role of local conditions, we quantified SGS in 21 populations of the threatened forest tree Juglans cinerea (butternut). We observed a wide range across the populations in several measures of SGS (mean Sp statistic: 0.020, range: ∼0–0.04; mean F1: 0.06, range: ∼0–0.13). We found correlations between local conditions and several measures of SGS. Specifically, ecological zone (riparian/ upland), and degree of habitat linearity strongly correlated to the Sp statistic and the distance over which positive relatedness was observed (Dpos). In contrast, degree of aggregation was significantly associated with high kinship in the smallest distance class (F1), and a signature of colonization. Land-use history had minor effects compared to spatial or ecological factors. Population age structure significantly influenced F1, but not other metrics. Our work suggests that spatial, demographic, and environmental factors interact to determine SGS, and emphasizes that different aspects of SGS are not necessarily influenced by the same ecological factors. An influence of local conditions on SGS has implications for population genetic response to rapidly changing habitats as well as forest restoration.