东北草原植物残体腐解动态研究(简报)

Decomposition dynamics of plant residues in natural meadow in northeast China

东北草原植物残体腐解试验表明 ,植物残体腐解动态变化规律一致 ,前期腐解快 ,以后变慢。羊草的碳素残留率比草木樨的高 ,对于植物的不同器官残体 ,根的碳素残留率最高 ,茎次之 ,叶最低。试验结果还表明 ,植物残体不同埋深对碳素残留率也有影响 ,埋深 7cm,植物残体的碳素残留率最低 ,埋深 15 cm稍高 ,覆盖在土壤表面的最高。这说明植物中的羊草、植物残体中的根和茎以及土壤深层的残体都有利于土壤有机质的积累 ,而草木樨、植物残体中的叶以及浅层植物残体都有助于养分向土壤释放。羊草和草木樨残体混合物的碳素残留率介于草木樨和羊草之间 。

Results of decomposition experiment applying plant residues in natural meadow in northeast China showed that there were the same change trends. The decomposition speed of plant residues was higher during earlier stage after applied, and lower during later stage. But there were significant differences among the residual organic carbon of plant residues. The residual organic carbon of Leymus chinensis residues was higher than that of Melilotus Suavedens residues. as far as the effects of different parts of plant residues on the residual organic carbon ,the root had it higher than the stem and the leaf, and the stem had it higher than the leaf. Experimental results also showed that buried depth of plant residues had effects on residual organic carbon. The residual organic carbon of plant residues buried 7 cm in depth was highest, and that of plant residues buried 15 cm in depth the second, and that of plant residues buried 0 cm in depth the lowest. Therefore, the root and stem of plant are advantageous to the accumulation of soil organic matter (SOM) while the leaf is advantageous to the nutrient releasing into hte soil. And deep root can help accumulate SOM.