| 摘要 |
<p>The plant propagation unit comprises a support carrying a layer of compost or the like, and a system of tubes through which a heating medium is passed to heat the compost. The tube system is contained between the compost above it and thermal insulation below whilst the medium is heated by a solar collector. The insulation is pref. polyurethane foam etc. with an aluminium or similar plate below it. A reflective layer, e.g. aluminium foil, may be arranged between the insulation and the tubes, and a metal plate, e.g. in aluminium or galvanised steel, may be provided between the tubes and the compost.</p> |
