浙江天童国家森林公园内几种蕨类植物的能量特征分析

蕨类植物广泛分布于浙江省的不同森林生态系统中,是林下草本层中生物多样性和初级生产力的重要组成部分.对浙江天童国家森林公园马尾松林和木荷+栲树林内主要蕨类植物里白(Diplopterygium glaucum)、芒萁(Dicranopteris pedata)、狗脊(Woodwardia japonica)、紫萁(Osmunda japonica)和乌蕨(Sphenomeris chinensis)的地上部分的灰分含量、干重热值和去灰分热值等能量特征进行了研究.结果表明:在5种蕨类植物中,里白、狗脊、芒萁和乌蕨在木荷+栲树林中的去灰分热值高于马尾松林,而紫萁在马尾松林中的较高;蕨类植物叶片热值高于叶轴的热值,叶片的去灰分热值与叶片年龄有关,较老叶片中贮存能量较多.狗脊含孢子的叶片热值高于不含孢子的叶片.里白、狗脊、芒萁等广布于该地草本层中,与其较高的热值有关.同其它4种蕨类植物相比,里白在该地的分布更加广泛,在林下占绝对优势,通过热值分析发现,里白的热值高于狗脊的,说明里白在能量利用和贮存中具有优势.

Energy analysis of several ferns in the Tiantong National Forest Park, Zhejiang Province

As the most important components within understory in the different forest ecosystems,ferns distributed broadly in large areas of Zhejiang Province.The ash content,the gross caloric and the ash-free caloric value of the five ferns,including Diplopterygium glaucum.Dicranopteris pedata,Woodwardia japonica,Osmunda japonica and Sphenomeris chinensis from Tiantong National Forest Park(TNFP),Zhejiang Province were studied in the paper.The results showed that the ash content,the gross caloric and the ash-free caloric value of the five ferns were different from that in the Schima superba+Castanopsis fargesii forest and Pinus massoniana forest.The ash-free caloric value of D.glaucum,D.pedata,W.japonica and S.chinensis within Schima superba+Castanopsis fargesii forest is higher than that within Pinus massoniana forest,contrarily,the ash-free caloric value of O.japonica within Schima superba+Castanopsis fargesii forest is lower than that within Pinus massoniana forest.The ashfree caloric of fronds iS higher than that of rachis,and the ash-free caloric incresed in the relatively old fronds.The results also showed the ash-free caloric of fronds with spore were higher than those of fronds without spore.Generally,the ash-free calorie value of D.glaucum was higher than that of W.japonica,it suggested that D.glaucum distributed commomly more than W.japonica did.