The physico-chemical properties of serpentine soils lead to strong selection of plant species. Whereas many studies have described the serpentine flora, little information is available on the fungal communities dwelling in these sites. Asbestos minerals, often associated with serpentine rocks, can be weathered by serpentine-isolated fungi, suggesting an adaptation to this substrate. In this stu...

Specialization and concomitant trade-offs are assumed to underlie the non-neutral coexistence of lineages. Trade-offs across heterogeneous environments can promote diversity by preventing competitive exclusion. However, the importance of trade-offs in maintaining diversity in natural microbial assemblages is unclear, as trade-offs are frequently not detected in artificial evolution experiments....

Transectional studies of Lasthenia californica in the Jasper Ridge Biological Preserve (Stanford University) have documented the existence of two races (A and C) based upon flavonoid chemistry, achene morphology, allozymes, and flowering time differences. The two races coexist on a serpentine outcrop and have maintained a sharply defined pattern of distribution for a period of at least 15 yr. T...

Shifts in species' traits across contrasting environments have the potential to influence ecosystem functioning. Plant communities on unusually harsh soils may have unique responses to environmental change, through the mediating role of functional plant traits. We conducted a field study comparing eight functional leaf traits of seventeen common species located on both serpentine and non-serpen...

Water is the principal limiting resource for Californian Mediterranean-climate plants. The relationship between rainfall variation and the abundance and distribution of plant species was investigated at the Jasper Ridge Biological Preserve near Stanford University. Five years of rainfall data (1986-1990) were combined with a yearly census of plant species on a 100m transect to relate inter-annu...

Serpentine soils represent stressful habitats where plants have to cope with heavy metals, moisture limitation and low nutrient availability. We propose that facilitation is an important mechanism structuring plant communities under such stressful conditions. Facilitation has been shown to generate the spatial association of species, forming discrete vegetation patches of phylogenetically dista...

Effects of simulated serpentine soil conditions (elevated Mg:Ca ratio and Ni concentration) on seedlings from populations of Virginia pine (Pinus virginiana Mill.) from serpentine and non-serpentine sites were evaluated in sand culture. We determined (1) how seedlings are affected by elevated Mg:Ca ratio and Ni concentrations, (2) if there are interactive effects between Mg:Ca ratio and Ni conc...