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Plants that have evolved to survive on metal-rich soilsmetallophytes-have key values that must drive research of their unique properties and ultimately their conservation. The ability of metallophytes to tolerate extreme metal concentrations commends them for revegetation of mines and metal-contaminated sites. Metallophytes can also be exploited in environmental technologies, for example, phytostabilization, phytoremediation, and phytomining. Actions towards conserving metallophyte species are imperative, as metallophytes are increasingly under threat of extinction from mining activity. Although many hundreds of papers describe both the biology and applications of metallophytes, few have investigated the urgent need to conserve these unique species. This paper identifies the current state of metallophyte research, and advocates future research needs for the conservation of metallophyte biodiversity and the sustainable uses of metallophyte species in restoration, rehabilitation, contaminated site remediation, and other nascent phytotechnologies. Six fundamental questions are addressed: (1) Is enough known about the global status of metallophytes to ensure their conservation? (2) Are metallophytes threatened by the activities of the minerals industry, and can their potential for the restoration or rehabilitation of mined and disturbed land be realized? (3) What problems exist in gaining prior informed consent to access metallophyte genetic resources and how can the benefits arising from their uses be equitably shared? (4) What potential do metallophytes offer as a resource base for phytotechnologies? (5) Can genetic modification be used to ''design'' metallophytes to use in the remediation of contaminated land? (6) Does the prospect of using metallophytes in site remediation and restoration raise ethical issues?

Mining causes the destruction of natural ecosystems through removal of soil and vegetation and burial beneath waste disposal sites. The restoration of mined land in practice can largely be considered as ecosystem reconstruction-the reestablishment of the capability of the land to capture and retain fundamental resources. In restoration planning, it is imperative that goals, objectives, and success criteria are clearly established to allow the restoration to be undertaken in a systematic way, while realizing that these may require some modification later in light of the direction of the restoration succession. A restoration planning model is presented where the presence or absence of topsoil conserved on the site has been given the status of the primary practical issue for consideration in ecological restoration in mining. Examples and case studies are used to explore the important problems and solutions in the practice of restoration in the mining of metals and minerals. Even though ecological theory lacks general laws with universal applicability at the ecosystem level of organization, ecological knowledge does have high heuristic power and applicability to site-specific ecological restoration goals. However, monitoring and management are essential, as the uncertainties in restoration planning can never be overcome. The concept of adaptive management and the notion that a restored site be regarded as a long-term experiment is a sensible perspective. Unfortunately, in practice, the lack of post-restoration monitoring and research has meant few opportunities to improve the theory and practice of ecological restoration in mining.

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Curing of polymer matrices by ultraviolet (UV) irradiationcan be applied to a variety of processes in the production of composite components, as long as the component can be directly irradiated. Wet lay-up techniques, vacuum infusion type processes with UV-transparent membranes, filament winding, and prepreg processes have been adapted to UV curing. Unlike in thermal curing, the curing time is in the order of magnitude of minutes rather than hours, which means a significant reduction in cycle time. The radiation can be generated by a variety of sources suitable for various specific applications and different curing strategies. The most frequently used radiation sources are mercury arc lamps. Because of the absorption of radiation passing through matter, the thickness of laminates for efficient application of UV curing is limited. The curing mechanism is either radical polymerization for acrylate-based resins or cationic polymerization for epoxies and vinyl ethers. The properties of the UV-cured polymer matrix are determined by the cross-linking density. This depends on the type and concentration of the photoinitiator and of the (optional) diluents, the intensity and the duration of the irradiation, and the temperature at which the curing process takes place. POLYM. COMPOS., 27: 119 -128, 2006.