Development And Application Of Graphics Information Triploid Populus Tomentosa

Triploid Populus tomentosa is the best papermaking lumber for its short rotation,fast growth, white lumber and long textile fiber.At present,it has obtained many papermaking enterprises' approval,operators want to produce more and better timber quickly on limited land.This research chose Pinggu to carry on the forest nutrition experiment.Leaf nutrient variation of in a growing season,different age and varieties,soil nutrient depletion were studied.Results showed that:(1)In a growing season,N concentration in leaves decreased,the range is:26.38-10.08g.kg^-1.P dropped and then rose,the range is:1.28-0.74 g.kg^-1.K lowered,the range is:19.21-11.19g.kg^-1.Ca increased and the range is 6.46-24.42g.kg^-1.Mg rose and then dropped,the range is 2.16-5.17 g.kg^-1.(2)With the growth of age,N,P,K concentration lowered,and Ca,Mg increased.The difference of N, K,Ca didn't vary significantly,but P,Mg reached a significant level.(3)The major element content between triploid and diploid populus tomentosa varied significantly. The content of N,K,Mg in triploid clone is higher than diploid,but content of Ca in diploid clone is higher than triploid,content of P between the two clones is not obvious.(4)The concentration of organic matter increased yearly in the surface,and decreased in the deep.The entire N content increased yearly;available P,K content in the surface was higher than that in deep.(5)The concentration of N,P,K in the soil have strong correlation with what in the leaves. Correlation coefficient of N is 0.903,P is 0.85,and correlation coefficient of K is 0.73.(6)The diameter of triploid Populus tomentosa correlated positively with N,P,K,Ca and negatively correlated with Mg.The height correlated positively with N,P,Mg,but negatively with K,Ca.