Status of native species in threatened Mediterranean habitats: the case of Pancratium maritimum L. (sea daffodil) in Lebanon

摘要

The Mediterranean coast of Lebanon is being destroyed by urban expansion and other human activities. Coastal vegetation communities, especially those on prime tourist areas, such as sandy beaches, are under particular threat. This study investigated a native coastal species, Pancratium maritimum L. (Amaryllidaceae), to contribute to knowledge of these highly threatened habitats and investigate possible strategies for their conservation. Ecogeographic surveys, population dynamics and molecular analysis were undertaken. Individual populations occupied areas ranging from 704 and 32,000 m(2) and differed in their structure and reproductive ability. Clump density ranged between 0.002 to 5.6 Clumps m(-2). Percent fecundity varied significantly between populations and ranged between 0.07 and 57.4%. In contrast, seedling recruitment and survival were consistently nil or low in all populations. The average Nei's unbiased genetic identity based on RAPD data was 0.09, suggesting that the species is self-pollinated. Cluster analysis indicated that populations did not group according to geographic proximity. F statistics revealed higher variation within than between populations. According to IUCN Red List Criteria at the Regional Level the current status of P. maritimum in Lebanon is Vulnerable [VU B I ab (i,ii,iii,iv,v) + 2ab (i,ii,iii,iv,v)]. This could rapidly move to a higher category of threat unless conservation measures are adopted very quickly.