Human disturbance, habitat degradation and niche shift: the case of the endemic Calendula maritima Guss. (W Sicily, Italy)

摘要: Calendula maritima Guss. is a plant endemic to the coastline of W Sicily, whose distribution range experienced dramatic shrinkage during last centuries along with degradation and fragmentation associated assemblages. According that, it can represent an effective target species test response coastal biota anthropogenic disturbance. In order better understand niche width C. maritima, communities in which still found have been investigated through vegetation releves carried out on different size plots. Although sea marigold has considered as pioneer typical shifting dunes, field investigations highlighted that also occurs Data concerning smaller plots allowed identification three groups releves: one showing highest number trivial ruderal plants, another hosting some psammophilous species, third linked rocky surfaces. These do not cluster issuing from literature, 40 years ago, mostly focused dune ecosystems. It assumed strong floristic differences between these two types may be destruction dunes occurred over decades, caused local extinction many other plants related this habitat. However, could reflect lack historical populations growing sites. Interestingly, gradual expansion was highlighted, likely depending ability colonize new increasing Our results confirm hybridization contiguous congener fulgida Raf. major threat for conservation remnant maritima.