晋西北黄土区幼龄柠条细根的净生长速率  

The net growth rate of fine roots of Caragana korshinskii seedlings in the Loess Plateau region,Northwest Shanxi

作　　者：王孟本[1] 荀俊杰[1] 陈建文[1] 史建伟[1] 

机构地区：[1]山西大学黄土高原研究所,山西太原030006

出　　处：《生态学报》2010年第5期1117-1124,共8页Acta Ecologica Sinica

基　　金：山西省自然科学基金资助项目(2007021032);山西省科技攻关资助项目(2006031014)

摘　　要：以晋西北黄土区5年生柠条(Caragana korshinskii)人工林为研究对象,使用微根管技术对林地100cm土层深度的柠条细根生长动态进行观测。以根长密度(RLD,mm.cm-3)为基本参数,以净生长量(RLDnet,mm.mm-3)和净生长速率(RLDNGR,mm.cm-.3d-1)为相应导出参数,对2007年生长季(4-9月份)柠条细根的RLDNGR及其与环境因子气温、降雨量、土壤温度、土壤水分的关系进行了探讨。结果表明:柠条细根的RLDnet为(2.923±1.767)mm.cm-3;RLDNGR为(0.113±0.069)mm.cm-.3d-1。50-100cm土层是柠条细根生长的活跃区,其细根RLDNGR是0-50cm土层细根的1.5倍。柠条细根生长的季节变化趋势呈单峰型,4月初至8月初RLDNGR逐渐增大,8月中旬RLDNGR达到最大,之后逐渐减小,9月下旬RLDNGR出现负值。统计分析表明,柠条细根的RLDNGR与气温呈显著正相关。年生长季柠条细根的累计净生长量为14.613mm.cm-3;累计净生产力为1.461×108m.hm-2。The fine root growth patterns of Caragana korshinskii in a 5-year old plantation in the Loess Plateau region of Northwest Shanxi were investigated by using minirhizotron technique.By defining root length density（RLD,mm·cm-3）as basic fine root parameter,and net root length density（RLDnet,mm·cm-3）and net root growth rate（RLDNGR,mm·cm-3·d-1）as derived parameters,the RLDNGR of C.korshinskii seedlings and its relationships with the environmental factors（air temperature,precipitation,soil temperature and soil water content）in the growth season of 2007 were analyzed.The results showed that the averaged RLDnetwas（2.923±1.767）mm·cm-3;and the averaged RLDNGR was（0.113±0.069）mm·cm-3·d-1.The 50-100cm soil layers were the primary growth zone of the fine roots,where the averaged RLDNGR was 1.5 times that of 0-50cm soil layers.There existed a distinctive seasonal change pattern of RLDNGR from April to September,and it increased rapidly from early April to early August and reached a peak in the middle of August,and then decreased gradually,and became negative in late September.The seasonal growth pattern of fine roots in C.korshinskii seedlings was significantly and positively related to air temperature.The cumulative RLDnetwas 14.613mm·cm-3 in the annual growing season,and the cumulative net productivity was 1.4613×108m hm-2 in the same period.

关 键 词：细根 柠条 根长密度 微根管 环境因子 黄土区 

分 类 号：S793.3[农业科学—林木遗传育种]