长白山次生针阔混交林叶凋落物中有机物分解与碳、氮和磷释放的关系

采用分解袋法,研究了长白山次生针阔混交林内9种树种叶凋落物34个月的分解过程.结果表明:在次生针阔混交林中,不同树种叶凋落物的初始N和P浓度存在很大差异，叶凋落物分解速率(k)与初始N浓度和C/N显著相关.有机物剩余百分率与C剩余百分率呈显著的线性正相关关系，与N和P剩余百分率之间呈显著的二项式回归关系. N和P剩余百分率在初期阶段随有机物分解而增加，达到峰值后逐渐降低. 随着有机物剩余百分率的下降，C/N和C/P均呈逐渐降低趋势，各种叶凋落物之间C/N和C/P的差异逐渐减小，分解末期分别趋近于23和350. 随有机物剩余百分率的降低, N/P变化不明显，当有机物剩余百分率低于25%时，不同树种叶凋落物之间N/P差异显著下降. 有机物剩余百分率可用来预测C、N和P的剩余百分率. 

Emergy evaluations on development level of recycle economy in Liaoning Province

By the method of emergy analysis, the development level of recycle economy in Liaoning Province was evaluated from the aspects of emergy flux, emergy economy, ecological environment, and comprehensive index. The results showed that the development of economy in Liaoning Province was on a relatively high level. With the progress in practicing clean production, constructing ecological industry chain and recycle network, and implementing cascade use of material/energy flow, reuse of waste water, and comprehensive utilization of resources, etc. , the energy consumption per ten thousand GDP, wastewater discharge per ten thousand GDP, and solid waste discharge per ten thousand GDP were all reduced. However, the fast growth of economy was mostly supported by the consumption of a great lot of un-renewable resources, and the ability of system sustainable development was descending. To have an overall improvement in the development sustainability in Liaoning Province, great efforts should be made on increasing the emergy use efficiency, enhancing the capability of conserving and exploiting renewable resources, reasonably utilizing un-renewable resources, and upgrading the recycle use level.