| Shanxi province is the most concentrated and typical cinnamon region in China, and about 28.8% of the cinnamon region lies in it. Since 1982, great changes have take place in planted structure, fertilization, and fertilizer inputs in cinnamon region. It is necessary to carry out a research on spatiotemporal variations of soil nutrients on cinnamon soil which can work as guidance for nutrient management, and it has an important effect in improving agricultural production, environment quality as well as rural incomes.Zong'ai town which lies in Shouyang county was selected as the research location, based on the 2nd national soil survey data in 1982, and the Zong'ai town's soil nutrient survey data in 1998 and 2008, the spatiotemporal variation of soil nutrient is studied and the reasons are discussed. Furthermore, some measures to increase the productivity of cinnamon soil were proposed. The conclusions are as follows:1. Compared with 1982, the soil organic matter content in 1998 increases 4.36 g/kg, and compared with 1998, there is a decrease of 2.06 g/kg in 2008. Especially,59.25% of the farmland's organic matter content belongs to the low level in 2008. The output of organic fertilizer was less than organic matter yield crops needed, which resulting in decreased organic matter content.From 1982 to 2008, the content of total nitrogen increases year by year, for instance there is an increase of 20.8% in 2008 compared with 1982. In 2008,97.23% of farmland's total nitrogen content belongs to low level in this region. Fertilizer application increases year by year, and the content of total nitrogen is also increases.Compared with 1998, the content of total phosphorus in 2008 decreases by 4.35%. In 2008, all the soil's content of total phosphorus is at the low level, and natural factors play the main role.From 1998 to 2008, the total potassium content decreases by 16.09%. All the soil's total potassium content is at the low level in 2008.The supply of potassium fertilize is a few correspondingly, so that crops take the nutrient from soil.2. Compared 2008 with 1998, available nitrogen content decreases by 0.7%, and the proportion that the available nitrogen content is at the low level is 99.26% in 2008. Natural factors play the main role.Available phosphorus content in 1998 increases 2.01 mg/kg compares with that in 1982. But in 2008 it decreases slightly compared with that in 1998. In 2008,94.37% of the farmland's available phosphorus is at the low level. Calcium superphosphate fertilizer input in 2008, it increases only by 1.7% compared with that in 1982. From 1982 to 2008, the content of available potassium increases year by year. In 2008, it increases by 41.2% compared with that in 1982, and the proportion that the soil's content of available potassium is at low level is 38.83%. Stalks and fertilizer application can increase the available potassium content in some degree.3. Compare 2008 to 1998, soil available iron, available Manganese, available copper, content decreased by 28.6%,36.2%,24.4% respectively, and available zinc content increased by 14.8%.69.25% of the agricultural land area fertilizing zinc and 56.04% of agricultural land fertilizing Manganese fertilizer is effective,20.88% of the agricultural land fertilizing zinc and 39.56% of agricultural land fertilizing Manganese fertilizer may be effective. Trace elements fertilizer is rarely used in this region which leading to a decrease on the content of soil available iron, available Manganese, and available copper. The effective increase in zinc content may be caused by the absorption different between varieties of corn or a few farmers have applying small amounts of zinc or zinc special fertilizer for crops.Based on the spatiotemporal variability for soil nutrients and the reason analysis mentioned above together with the research result of a long-term fertilization located, some proposal to maintain and improve soil fertility in cinnamon region is given out.
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