@article {111,
	title = {Population density as a predictor of genetic variation for woody plant species},
	journal = {Conservation Biology},
	volume = {13},
	year = {1999},
	note = {199900314083ArticleEnglish},
	month = {1999},
	pages = {1079-1087},
	abstract = {As the focus of conservation biology shifts toward multispecies and ecosystem conservation and management, a principal question becomes how we manage species to conserve their long-term evolutionary potential. Few criteria exist for prioritizing which populations within a species should be protected to conserve maximal genetic variation. We designed this study to explore the genetic consequences of using population density as a criterion for selecting populations of woody plant species for conservation. Population density may be an effective gauge of genetic variation for two reasons. First, density often reflects ecological population size, particularly for continuously distributed species, and density is much easier to measure in the field than population size. Second, from an individual species{\textquoteright} perspective, population density may be an indicator of habitat quality. We evaluated the relationship between standard genetic diversity indices and densities of seedlings, small trees, andlarge trees, and we investigated the association between genotypic composition and density measures with canonical correlation analysis for three common tree species (Carya tomentosa, Sassafras albidum, and Quercus alba) from the Missouri Ozarks. We found that population density was not correlated with genetic diversity in large populations of plant species, but density was associated with genotypic composition of populations. That is, populations with small densities had different genotypes than those with large densities. To sample a maximal amount of regional genotypic variation, we recommend choosing plant populations representing a range of densities. Findings from our study should be generally applicable to plant populations that have occupied habitats long enough for natural selection to affect local genotypic composition. Used in conjunction with other established criteria, population density may be a useful rule of thumb for conservation practitioners concerned with themaintenance of adaptive genetic variation in plant species.},
	keywords = {-, -albidum (Lauraceae-), -Plants, [26070-] Fagaceae-, [26215-] Juglandaceae-, [26245-] Lauraceae-, Angiospermae-, Carya-tomentosa (Juglandaceae-), Conservation-, Dicots-, Dicotyledones-, Fagaceae-: Angiosperms-, genetic-variation, habitat-quality, Juglandaceae-: Angiosperms-, Lauraceae-: Angiosperms-, Missouri-Ozarks: Missouri-, Nearctic-region, North-America, Plantae, Plantae-, Plants-, population-density, population-size, Population-Studies, Quercus-alba (Fagaceae-), Sassafras, Spermatophyta-, Spermatophytes-, USA-, Vascular, Vascular-Plants},
	author = {Gram, W.-K. and Sork, V.-L.}
}
@article {65,
	title = {Pollen movement in declining populations of California Valley oak, Quercus lobata: Where have all the fathers gone?},
	journal = {Molecular Ecology},
	volume = {11},
	year = {2002},
	note = {200200321338ArticleEnglish},
	month = {2002},
	pages = {1657-1668},
	abstract = {The fragmented populations and reduced population densities that result from human disturbance are issues of growing importance in evolutionary and conservation biology. A key issue is whether remnant individuals become reproductively isolated. California Valley oak (Quercus lobata) is a widely distributed, endemic species in California, increasingly jeopardized by anthropogenic changes in biota and land use. We studied pollen movement in a savannah population of Valley oak at Sedgwick Reserve, Santa Barbara County, to estimate effective number of pollen donors (Nep) and average distance of effective pollen movement (delta). Using TWOGENER, our recently developed hybrid model of paternity and genetic structure treatments that analyses maternal and progeny multilocus genotypes, we found that current Nep = 3.68 individuals. Based on an average adult density of d = 1.19 stems/ha, we assumed a bivariate normal distribution to model current average pollen dispersal distance (delta) and estimated delta = 64.8 m. We then deployed our parameter estimates in spatially explicit models of the Sedgwick population to evaluate the extent to which Nep may have changed, as a consequence of progressive stand thinning between 1944 and 1999. Assuming that pollen dispersal distance has not changed, we estimate Nep was 4.57 individuals in 1944, when stand density was 1.48. Both estimates indicate fewer effective fathers than one might expect for wind-pollinated species and fewer than observed elsewhere. The results presented here provide a basis for further refinements on modelling pollen movement. If the trends continue, then ongoing demographic attrition could further reduce neighbourhood size in Valley oak resulting in increased risk of reproductive failure and genetic isolation.},
	keywords = {[26070-] Fagaceae-, adult-density, Angiospermae-, declining-populations, Dicots-, Dicotyledones-, Fagaceae-: Angiosperms-, genetic-isolation, human-disturbance, Nearctic-region, North-America, Plantae-, Plants-, pollen-movement, Population-Genetics: Population-Studies, Quercus-lobata (Fagaceae-): California-Valley-oak, reproductive-failure, Santa-Barbara-County: California-, Sedgwick-Reserve, Spermatophyta-, Spermatophytes-, TWOGENER-model, USA-, Vascular-Plants},
	author = {Sork, V.-L. and Davis, F.-W. and Smouse, P.-E. and Apsit, V.-J. and Dyer, R.-J. and Fernandez-M, J.-F. and Kuhn, B.}
}
