模拟氮沉降和混栽对杉木和浙江楠根系生长的影响  

Effects of Simulated Nitrogen Deposition and Cultivation on Root Growth of Cunninghamia lanceolata and Phoebe chekiangensis

作　　者：王镜如 陈圣贤 伊力塔[1] 俞飞[1] 刘美华[1] 黄华宏[1] 宋琦[2] Wang Jingru;Chen Shengxian;Yi Lita;Yu Fei;Liu Meihua;Huang Huahong(Zhejiang Agriculture and Forestry University,Hangzhou 311300,P.R.China)

机构地区：[1]浙江农林大学,杭州311300 [2]杭州万向职业技术学院

出　　处：《东北林业大学学报》2021年第8期24-30,共7页Journal of Northeast Forestry University

基　　金：国家自然科学基金项目(31971623);浙江省教育厅一般科研项目(Y201942554)。

摘　　要：为探明杉木-浙江楠混栽状态下根系生长特征及其对日益严重的氮沉降的响应,通过控制模拟氮沉降(0、45 kg·hm^(-2)·a^(-1))和不同种植方式(杉木和浙江楠纯栽、杉木-浙江楠1∶1行状混栽)两个条件,分析不同种植方式和氮沉降模式对杉木、浙江楠根系生长的影响。试验结果表明:混栽抑制杉木根系生长,促使杉木根冠比降低;纯栽条件下,施氮导致杉木根系生长受磷限制,与浙江楠混栽能够解决施氮造成的磷限制问题;氮沉降提高了浙江楠土壤氮有效性,导致其倾向将更大比例生物量分配至地上部分竞争光资源,从而抑制了自身根系生长;浙江楠一旦建立地上竞争优势,将反馈地下部分从而造成其根生物量升高。The experiment was conducted to study the characteristics of root competition and its response to increasingly severe nitrogen deposition under mixed planting of Cunninghamia lanceolata and Phoebe chekiangensis.The experiment included three cultivation types(C.lanceolata+C.lanceolata,P.chekiangensis+P.chekiangensis,C.lanceolata+P.chekiangensis)and two N treatments(0 and 45 kg·ha^(-1)·a^(-1)).The root morphology and function of interspecific competition and its response to nitrogen deposition were analyzed.The results showed that Mixed planting inhibits the growth of C.lanceolata roots and promotes a decrease in the root shoot ratio of C.lanceolata.Nitrogen treatment has no significant effect on the roots of pure C.lanceolata due to the P limitation,mixed planting with P.chekiangensis can solve the P limitation caused by nitrogen deposition.The effect relieved the P limitation of the growth of C.lanceolata roots,so that nitrogen deposition promoted the growth of mixed C.lanceolata roots.Nitrogen deposition improves the soil nitrogen availability of P.chekiangensis,resulting in its tendency to allocate a greater proportion of biomass to competing light resources above ground,thereby inhibiting its own root growth.Once the biomass allocation strategy of P.chekiangensis under nitrogen addition establishes an above-ground competitive advantage,it will feed back the underground part and thus increase its root biomass.

关 键 词：氮沉降 种间竞争 根系 杉木 浙江楠 

分 类 号：S725.1[农业科学—林木遗传育种]