The genetic diversity of Cistus ladanifer ssp. ladanifer (Cistaceae) growing on ultramafic and non-ultramafic (basic and schists) soils in the NE of Portugal was studied in order to identify molecular markers that could distinguish the metal-tolerant ecotypes of this species. Random Amplified Polymorphic DNA (RAPD) markers were used in order to estimate genetic variation and differences between...

A gravity and geologic survey was carried out over a port ion of the Nelson ultramafic belt of the South Island . In this region, the ultramafic rocks outcrop over a 5-mile-wide belt and abut against the Alpine greywacke along the right lateral transcurrent Alpine Fault. The dunite and peridotite of the ultram afic belt as well as the overlying geosynclinal sediments strike north . At their sou...

ONE petrological approach to upper mant le studies is to determine which ultramafic rocks represent mantle material. Ultramafic rocks occur in a variety of field and petrographic associations : in recent reviews, Wyllie [1967b, 1968] outlined eleven petrographic associations, some with subdivisions. In this summary, it is convenient to consider these in four larger groups: (1) layered, stratifo...

anomolously low A1203, low Ti02 and are enriched in chromium and nick~A We present petrographic and chemical c ata on the Kamloops Lake picritic tmalts as we1 I as the stratigraphic setting for thwe ultramafic lavas. Age constraints derive From field relationships, Mineral chemistry indicates th 31 these ultramafic rocks represent mantle-deri.ed material which has undergone: minimal differentia...

This paper reviews the concentration of heavy metals particularly Cr and Ni in the serpentinised and ultramafic soil/rock throughout the different geological regions in the world which are produced due to anthropogenic means or due to natural weathering. Poor nutrient content, low Ca: Mg ratio, higher concentration of heavy metals is major reason for the sparse vegetation on such soil. The vege...

Background The ubiquity of nickel in the environment and its common presence in food and water mean that humans are constantly exposed to nickel. Although nickel is not acutely toxic at low levels, it is a carcinogen and has been linked to cellular oxidative stress [1]. Soils that develop on serpentinite, a metamorphic rock type derived from ultramafic igneous rocks (and the state rock of Calif...

The mam plant communities of ultramafic (serpentine) outcrops of a Mediterranean area in central Italy are described and their successional pathway discussed. Four vegetation stages are distinguished: a) an endemic garigue stage, with high percentage of exposed rocky soil belonging to Armerio-Alyssetum bertolonii; b) a garigue stage similar to the previous one but with several Mediterranean eve...