Spatial distribution patterns and implications for conservation ofScrophularia takesimensis (Scrophulariaceae), an endangered endemic species on Ulleung Island, Korea

Abstract

As part of an on-going effort to conserve endangered and endemic Scrophularia takesimensis (Scrophulariaceae), we analyzed its spatial distribution patterns by applying an index of dispersion, plant-to-all-plant distances, and the varying quadrat size method. Three indices --Dispersion, Morisita, and Standardized Morisita --all revealed clumping with small aggregates, and distances between aggregates were more or less regular. The asymptote level occurred at a distance of 20 to 30 m; the distance showing 90% of cumulative frequency coincided with 20 to 21 m; 95%, 24 to 25 m; and 99%, 31 to 32 m. The 20 m• 20 m and 40 rex40 m quadrats contained 25 and 40 plants, respectively. We conclude that this number of individuals and size of area are the minimum required for the conservation of this species.

Distribution and conservation status of the Critically EndangeredScrophularia takesimensis, a plant endemic to Ulleung Island, Republic of Korea

“…All subpopulations were in previously known sites and we did not record any new locations. Of the previously known subpopulations (Ahn, 2005;Lim et al, 2008;Han et al, 2010) we were unable to locate 16 (29%; Fig. 1b) and conclude that the number of subpopulations is decreasing.…”

Population characteristics of endangered species Taxus chinensis var. mairei and its conservation strategy in Shanxi, China

“…Disturbance might have more negative effects on young rather than on adult individuals because young trees were easier to cut than adult ones (Luijten et al 2000;. Another obvious change of density was in the classes VI-VII which was due to mortality changes in the different age classes (Lim et al 2008). Perhaps environmental action had effects on this swing (Lindborg and Ehrlen 2002;Zhang 2004).…”

“…Another obvious swing was in class VII. These changes were related to mortality in the different classes (Zhang 2004;Lim et al 2008).…”

Endangered Plants in Novel Urban Ecosystems Are Filtered by Strategy Type and Dispersal Syndrome, Not by Spatial Dependence on Natural Remnants

“…Point pattern analysis has already been widely applied in nonurban areas to assess the dependence of endangered plant species on specific habitat patches of other species (Wehenkel et al, 2015). Further examples involve work on the effects of animalmediated dispersal of an endangered shrub (Rodríguez-Pérez et al, 2012), or on the minimum areas for the conservation of an endangered plant (Lim et al, 2008). Even if the importance of spatial patterning for biodiversity conservation in cities is increasingly acknowledged (Rastandeh et al, 2017), insights into related spatial patterns and processes are scarce because exact spatial information on the locations of endangered species in urban landscapes is often missing.…”