不同供氮水平对栓皮栎播种苗光响应曲线的影响  

Effect of different nitrogen supply on light-response curves of Quercus variabilis seedlings

作　　者：杨自立[1] 马履一[1] 贾忠奎[1] 王梓[1] 

机构地区：[1]北京林业大学省部共建森林培育与保护教育部重点实验室

出　　处：《北京林业大学学报》2011年第5期56-60,共5页Journal of Beijing Forestry University

基　　金："十一五"国家科技支撑计划项目(2006BAD24B01);北京市教育委员会学科建设与研究生培养项目"北京城市生态环境建设产学研联合培养研究生基地";中央高校基本科研业务费专项(BLJD200904)

摘　　要：为科学制定栓皮栎播种苗氮肥管理措施,在砂培条件下,采用指数施肥的试验方法,设置4个供氮水平(0、120.6、216.4和329.2mg/(株·a)),探求不同的供氮水平对栓皮栎播种苗光响应特征曲线的影响。结果表明,在苗木生长的不同阶段,供氮量的差异对叶片光响应曲线的影响有所差别。生长初期,氮素对栓皮栎播种苗光响应特征曲线参数的影响不显著。速生期,缺氮(0mg/(株·a))严重影响苗木的光合性能,导致栓皮栎播种苗的光饱和点(LSP)、最大净光合速率(Pmax)、表观量子效率(α)偏低,而光补偿点(LCP)偏高;当供氮量从120.6mg/(株·a)增大到216.4mg/(株·a)时,苗木Pmax并没有明显变化,但苗木的LCP降低,LSP升高;过量供氮(329.2mg/(株·a))反而导致叶片的光合性能下降。生长末期,在其他处理苗木叶片光合性能均有不同程度下降的情况下,216.4mg/(株·a)水平的苗木仍然保持着相对较高的光合能力。In order to provide a theoretical foundation for nitrogen fertilizer management of Quercus variabilis seedlings,using exponential nitrogen fertilization regimes,the effects of nitrogen treatments on light-response curves of Q.variabilis seedlings were studied under sand-cultured condition.The seedlings were planted in pots,supplied with four nitrogen application levels（0,120.6,216.4 and 329.2 mg/（seedling·year））.The results show that various nitrogen application levels had different effects on the light-response curves of Q.variabilis leaves,depending on the growth phases.At the initiation phase,all the simulation parameters of light-response curves showed no significant differences among treatments.At the fast-growth phase,the lack of nitrogen weakened the photosynthetic capability of seedlings in treatment CK（0 mg/（seedling·year）） sharply,which reduced the light saturation point（LSP）,maximum net photosynthetic rate（Pmax） and the apparent quantum efficiency（α）;meanwhile,the light compensation point（LCP） expressed a trend of increase.When the nitrogen level was raised from 120.6 to 216.4 mg/（seedling·year）,no significant variation about Pmax was found between the two treatments;however,the LCP of the seedlings in 216.4 mg/（seedling·year） treatment was lower and the LSP was higher.Yet,excessive nitrogen supply（329.2 mg/（seedling·year）） played a negative role on the photosynthetic ability of Q.variabilis seedlings.At the later phase,relatively higher photosynthetic efficiency was maintained in the seedlings in 216.4 mg/（seedling·year） treatment,comparing with the common decline in other three treatments.

关 键 词：栓皮栎 播种苗 供氮水平 指数施肥 光响应曲线 

分 类 号：S718.43[农业科学—林学]