作 者 ：马莉薇,张文辉*,薛瑶芹,马闯,周建云
期 刊 ：生态学报 2010年 30卷 23期 页码：6512~6520
Keywords:Quercus variabilis, understory, forest gap, forest edge, environmental factors,
摘 要 ：栓皮栎(Quercus variabilis)是中国暖温带和亚热带林区的主要建群种，也是重要的栲胶、软木资源树种。为了阐明栓皮栎在不同生境条件下的种子成苗、实生苗生长及其与环境因素的关系，采用典型样地调查的方法，对秦岭北坡栓皮栎林3种生境中（林窗、林缘、林下）的栓皮栎种子库中种子数量、实生苗的存活数量、生长情况及生物量分配进行了研究，对影响实生苗生长发育的环境因素进行了相关分析。结果表明：林下、林窗和林缘的种子库中种子数量差异显著（P＜0.05），3种生境中能够萌发形成1a苗的种子数量少，种子能否萌发明显受枯枝落叶层厚度、光照强度和空气湿度的影响；栓皮栎种群有充足的苗库，其中较大年龄实生苗数量是种群能否持续更新的关键，林下、林窗和林缘中8a苗分别占该年龄实生苗总量的22.53%、45.60%和3187%，林窗中较大年龄实生苗的数量比林下和林缘多，林窗为栓皮栎实生苗的定居提供了有利条件；栓皮栎实生苗的生长与光照强度和空气温度显著正相关，与土壤含水量显著负相关，林窗中实生苗的生长状况和生物量积累均优于林缘、林下。林窗对栓皮栎种群更新有利。在今后的栓皮栎林的经营过程中，可以适当间伐，增加林窗数量，为种群可持续发育提供有利条件。
Abstract:Quercus variabilis distributed widely in the warm temperate and the subtropical area of China is not only an important constructive species of local forest but also a resource for tannin extracts and cork production. In order to understand the characteristics of seed bank, seed germination, seedling development and their influencing factors, 15 sampling plots belonging to 3 classes of habitats (understory, forest gap and forest edge) in Q. variabilis forests on the north slopes of Qinling Mountains where was the core distribution area of this species were studied. The number of Q. variabilis seeds in soil seed bank was investigated in 2008, the age structure, survival number of young seedlings, and the growth and biomass in relation to age development were investigated during the following year. Meanwhile, 7 environmental factors which might affect the germination of seeds and the growth of seedlings were also measured and analyzed. The main results were as follows: The number of intact seeds in seed banks, being different significantly (P＜0.05), were 3.60×103, 1.94×103 and 2.80×103 per 100 m2 respectively among plots for understory, forest gap and forest edge. They were resulted from that the processes of remove and predation, mildewing and immaturity affected the number of seeds to different extent among the 3 kinds of habitats. While remove and predation were the main way for the loss of seeds in the 3 kinds of habitats. Few seeds were able to germinate and develop to one-year-old seedlings, and the germinating process was observably influenced by the thickness of litter, radiation condition and air humidity according to the result of the correlation analysis. Q. variabilis population had plenty of young seedlings, however, the number of seedlings decreased dramatically with the age increase. The elder seedlings might play a key role in sustained regeneration of the population. The eight-year-old seedlings in understory, forest gap and forest edge accounted for 22.53%, 45.60% and 31.87% of the total number of the seedlings respectively. The number of seedlings in forest gap was more than that in the other 2 habitats. Forest gap was a kind of habitat which might be beneficial for the seedling establishment. The growth of height and biomass of the seedlings showed significant positive correlations with radiation condition and air temperature, but was negatively correlated with soil moisture significantly. The morphological traits including basal diameter, height, leaf area index and length of main root, and the biomass of stem, leaf and root of seedlings in forest gap were greater than those either at forest edge or in understory. The forest gap turned out to be favorable for the population regeneration of Q. variabilis. It might for the reason that the forest gap made the environmental factors, such as the radiation condition, air temperature and soil moisture etc. are different from those at forest edge or in understory, which were benefit to the growth of Q. variabilis seedlings. In the future, appropriate thinning techniques should be used to improve the number of the forest gap and provide favorable conditions for sustainable development of the Q. variabilis forests.
全 文 ：