%0 Journal Article
%T Comparison of light characteristics in different size gaps in eastern Liaoning montane secondary forests.<br>辽东山区次生林不同大小林窗光照特征比较
%A CHEN Mei
%A ZHU Jiao-jun
%A YAN Qiao-ling
%A WU Xiang-yun
%A TAN Hui
%A <br>陈梅
%A 朱教君
%A 闫巧玲
%A 吴祥云
%A 谭辉
%J 应用生态学报
%D 2008
%I 
%X With three different size gaps (G1, 670 m2; G2, 290 m2; and G3, 90 m2) in eastern Liaoning montane secondary forests of China as test objects, and through a continuous measurement of light intensity, the spatiotemporal distribution of photosynthetic photon flux density (PPFD) in the gaps was compared. The results showed that the diurnal variation of PPFD in the gaps was greater at northern than at southern position. The larger the forest gap, the broader the higher PPFD value area, and the more obvious the heterogeneity. As for the monthly variation of PPFD, the maximum PPFD at each position of the gaps appeared at the beginning of growth season (i.e., in April and May), while the minimum PPFD occurred in different months. The maximum PPFD at the eastern and western positions of each gap was basically appeared in the same months, and the PPFD was significantly higher in spring than in summer and autumn (P<0.05). The mean monthly PPFD at the centers of G1, G2, and G3 was 66.59%, 49.05%, and 30.37% of full sunlight, respectively, and in growth season, the PPFD at gap center was 37.8, 27.9 and 10.3 times higher than that at understory. It was suggested that owing to the different size and shape of forest gap and the effects of landform, the light intensity and its distribution in forest gap were different, being the key factors leading to the heterogeneity of regeneration pattern and the variation of species composition in forest gap.
%K PPFD<br>林窗
%K 次生林
%K 光照强度
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=42FEDDFE54F8BCD9D5FD1926ABDD7722&aid=F527877735499B1961A46284DE8681B2&yid=67289AFF6305E306&vid=2A8D03AD8076A2E3&iid=59906B3B2830C2C5&sid=05DCD46B802F239B&eid=B287A1A04CD05645&journal_id=1001-9332&journal_name=应用生态学报&referenced_num=2&reference_num=26