荒漠生态条件下植物残体分解和养分释放的研究

The Decomposition of Residue and Nutrient Releasing Under the Condition of Desert Ecosystem

以大豆秆为材料,研究了荒漠生态系统下残体的腐解率和腐解物的有机C、全N、全K含量、养分释放率以及C/N比的变化.结果表明:累积腐解率和有机C的分解率随时间的延长呈上升的趋势.0～1.5个月和1.5～3个月残体腐解率分别为18.9%和18.7%.随腐解时间的推移,残体全N的含量先逐渐上升,6个月后基本不变;全K含量0～1.5个月迅速下降,然后缓慢下降,3个月后基本不变.随腐解时间的延长,K的残留量逐渐减少,10个月后基本不变.N的释放量和释放率均为负值,整个腐解过程并没有N的释放.K的释放集中在0～1.5个月,释放率达75.8%,最终在90%左右.腐解残留物的C/N比先迅速下降,然后缓慢下降,6个月后基本不变,最终为35.9.

Quantitative studies on changes of decomposition rate, C/N ratio, N, K and organic C of bean residue during decomposition in desert ecosystem were carried out in Fukang, Xinjiang. Results showed that Accumulative decay rate and organic C decomposition rate of bean residue increased followed by the increasing of decomposition time. The decay rate in 0~1.5 month and 1.5~3 month were 18.9% and 18.7%, respectively. The total N increased gradually first, then kept on after 6 months. The total K decreased quickly at the first 1.5 month, then decreased slowly, then kept on after 3 months. The releasing amount and releasing rate of N were all minus. There was no releasing of N in the whole of decomposition. The releasing rate of K reached 75.8% in 1.5 months, then changed around 90%. The C/N ratio of decay remainders decreased quickly first, then didn't change on the whole after 6 months, and finally it was 35.9.