黄土高原区几种不同植物残落物碳、氮矿化特性研究  

Carbon and Nitrogen Mineralization of the Different Plant Residues from the Loess Plateau

作　　者：陈兴丽[1] 周建斌[1] 王春阳[1] 刘建亮[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《水土保持学报》2010年第3期109-112,126,共5页Journal of Soil and Water Conservation

基　　金：国家"十一五"科技支撑计划项目(2007BAD89B02);国家自然科学基金项目(40571087;40773057);西北农林科技大学拔尖人才支持计划(2006)资助

摘　　要：采用室内培养试验法(28℃下培养60 d)研究了采自黄土高原地区10种植物残落物的化学组成及施入土壤后碳、氮的矿化特性。结果表明,供试的几种乔木和草本残落物C/N比和木质素含量差异较大,有机碳的矿化率在整个培养期间的差异均达较显著水平。60 d培养结束后,草本植物残落物有机碳累积矿化率(平均值,33.14%)>灌木(27.80%)>乔木(23.23%)。培养结束时,3种乔木类植物残落物氮的平均固持率为39.67%;草本类的紫花苜蓿在整个培养期间释放氮素,培养结束后其氮累积矿化率为45.98%,而长芒草和白羊草在整个培养期间则固持氮素,培养结束后其氮素累积固持率分别为46.98%和50.56%。供试的3种灌木(沙棘、柠条及山桃)残落物的C/N比(15～16)和木质素含量(25～29)相近,其有机碳的矿化率差异相对较小,而残落物氮矿化率的差异达极显著水平(p<0.01),说明植物体的C/N比不是决定其氮素分解转化的唯一因子,植物残落物的其他化学特性也会影响其加入土壤后的转化。An incubation method was used to investigate the transformations and the C and N mineralization from the residues of ten plant species which commonly grow in the northern part of Loess Plateau.The results showed that there were significant differences in C mineralization from the trees and herbs residues during the incubation because of their significant differences in C/N ratios,and contents of total N and lignin.The averages of C mineralization rate of herbs residue was 33.14%,and higher than shrubs residue（27.80%）,and lowest was trees residue（23.23%）.At the end of incubation,the average N immobilization rate of the 3 trees residues was 39.67%.Net N mineralization occurred during the whole incubation period when alfalfa residue was added to the soil;after incubation time,the accumulation N mineralization rate was 45.98%.But the N immobilization occurred during the whole incubation period when Stipa bungeana,and old world bluestem residue were added to the soil;after incubation time,the accumulation N immobilization rates of Stipa bungeana,and old world bluestem residue were 46.98% and 50.56%,respectively.The C/N ratios（15～16） and the contents of lignin（25～29） of the 3 shrubs（korshinsk peashrub,sea buckthorn,and wild peach） residues were similar,their C mineralization were not significant differences.However,the amount of N mineralization rate from these residues were significantly different（p0.01）.This indicates that not only the C/N ratio but also the chemical composition of the plant residue affected their decomposition.

关 键 词：黄土高原 植物残落物 碳矿化 氮矿化 

分 类 号：S153.62[农业科学—土壤学]