| Organic matter,mineral nutrient,water-soluble salt and heavy metals were systematic analyzed in peat,oil shale and turf in Shaanxi.The results showed that the best advantage is the high content of organic matter,and the limitative factors are the high contents of asphalt,water-soluble salt(especially the content of SO42-is very high) and heavy metals(As)of the three mineral resources utilized in agriculture.Therefore,they can be used as one of the compositions of a mixed substrate,not directly as a cultural substrate. |