The Composition and Structure of Coarse Woody Debris in the Evergreen Broadleaved Forest After Ice Storm in Northern Guangdong Province

The composition and structure of the coarse woody debris (CWD) in the evergreen broadleaved forest after ice storm in northern Guangdong Province were studied by means of plot survey to compare the CWD existence form, species composition, DBH structure, and the CWD decay status of the forest stands at different aspects of the hills. The results showed that the CWD storage in the windward stand was 14.81 t/hm2, which was significantly higher than that of in the leeward stand (5.66 t/hm2) after the ice storm. There was great difference in the CWD existence form in stands at the different aspects. The CWD in the windward stands was mainly in the form of fallen logs, whereas the CWD in the leeward stands was mainly in the form of snags. The decay rate of fallen logs was much faster than that of the snags, so the former was principally in the moderately decomposed state, while the latter was mainly in the slightly decomposed state. The trees in large DBH classes in the windward stands accumulated a lot of ice, and then fell onto the ground became fallen logs, but the trees in small DBH classes in the leeward stands were killed by the low temperature and became the snags. The significant increase of CWD caused by the ice storm would have severely altered the forest structure and ultimately changed the succession process of the forest ecosystem. The fallen logs could apparently impact on the structure and function of forest ecosystems in a shortterm. However, the impact of the snags on the forest ecosystems would be a long term process, which requests long term quantitative research along the course.