Study On Leaf Traits Of Quercus Baronii In Yunqiu Mountain

Taking Quercus baronii in YunQiu scenic spot of south LvLiang Mountain as mainstudy object,this paper adopts the method of combining field investigation and indoorexperiments, the SPAD chlorophyll whith CM-1000SPAD Meter,the leaf area estimatedwith Li-3000A Leaf Area Meter, the saturated photosynthetic rate (Parea) with Li-6400portablephotosynthesis system, and the nitrogen content was measured by EA1108Elemental analyzer; Quantifying correlations among LDMC,SLA,The net photosynthesisbased On mass (Pmass), leaf nitrogen content per unit area (Narea), leaf nitrogen content perunit mass(Nmass), photosynthetic nitrogen use efficiency (PNUE) and trait differencesbetween plant species.The results showed that:(1) As elevation gradient rises up,Quercus baronii aspectratio, Chlorophyll, SLA,LA,Narea,Nmass, saturated fresh and dry weight, all of theirindicators have a first-increase-and-then-decrease trend and their peak value appears at thealtitude of1180m;however,LDMC has a significant negative correlation (p<0.05) with theelevation gradient; Parea, Pmassand PNUE reached the maximum value, indicating that thephotosynthetic capacity and PNUE of Quercus baronii at the altitude of1180m wascomparatively high, so pressure of survival was greater;(2) The LA of Quercus baronii issignificantly positively correlated with SLA and Nmass(p<0.01),negtively with Leaf drymatter(p<0.05),but obviously negatively with Narea(p<0.01); The leaf area of Quercusbaronii was significantly positively correlated with Parea, Pmassand PNUE（p<0.01）,Shows that the leaf traits of Quercus baronii grew toward conducive direction because ofthe increase of leaf area.(3) The leaf SLA of Quercus baronii has a positive correlationwith leaf length-width ratio(p<0.01)and a obvious positive correlation with Nmass(p<0.01),while significantly positively correlated with LDMC and Nmass(p<0.05); The SLAwas significantly positively correlated with Parea、Pmass、PNUE(p<0.01), Demonstrated theregularity features of Quercus baronii’ leaf traits at altitudinal variation;(4) The Nmass of Quercus baronii was significantly correlated with Pareaand Pmass(p<0.05), and a obviouspositive correlation with PNUE (p <0.01)；(5) The PNUE was significantly positivelycorrelated with Pareaand Pmass(p<0.01), while significantly positively correlated with Pareaand Pmass(p<0.05);(6) The paper took the leaf of Elaeagnus mollis as the object ofresearch. Leaf length、leaf width、SPAD value and different combinations of thesevariables were developed models to predict individual leaf area, saturated fresh weight,and dry weight of Ipomoea batatas，ten regression equations were compared. Selectfitting the best model as a predictive model in leaf area, saturated fresh weight and dryweight, The three models developed were as follows: individual leaf areaLA=-2.611+4.572W+0.106L2(R=0.983), saturated fresh weight SFW=-0.012+0.033W+0.00007LS(R=0.988), and dry weight，DW=0.007+0.014W+0.001L2(R=0.973). Thebest prediction model of LA, SFW and DW was was validated with the measured value.The results showed that the predicted values and measured values were highly consistent.It could be used to predict the LA, SFW and DW of actual unknown leaves.