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于2002年4月至11月,对孟加拉Chittagong (南部)林区天然纯林和肥沃地人工林树种更新情况进行了比较研究。共设100个3m×3m的样地(天然林50个,人工林50个)。共记录天然林更新树种64个,苗木密度为24767株/hm2;人工林更新树种40个,苗木密度为18633株/hm2。天然林更新量最大的树种为Castanopsis spp.(2200 株/hm2),其次是Glochidion lanceolarium (2183 株/hm2);人工林更新量最大的树种为Dipterocarpus gracilis (2117株/hm2),其次是Anogeissus acuminata (2000株/hm2)。对天然林而言, Castanopsis spp 的相对密度最高(8.88%), Glochidion lanceolarium 的相对频度最高(7.36%),Syzygium spp. 的相对富有度最高(3.79%),Glochidion lanceolarium的重要值指数最高(18.24%);对人工林而言,Dipterocarpus gracilis的相对密度最高(11.36%),Glochidion lanceolarium的相对频度最高 (9.71%), Dipterocarpus gracilis的相对富有度最高(5.92%), Glochidion lanceolarium的重要值指数最高 (23.32%)。Dipterocarpus gracilis 常见种在天然林和人工林都有更新苗木,但人工林的苗木要高于天然林。天然更新的苗木非常密集,但由于人为的干扰,这些更新的苗木通常达不到径干生长期。表4参35。
From April to November 2002, a comparative study was conducted on tree species regeneration of native and fertile plantations in the Chittagong (southern) forest region of Bangladesh. A total of 100 3m × 3m plots (50 natural forests, 50 plantations). A total of 64 species of regenerated natural forests were recorded. The density of seedlings was 24767 plants / hm2. 40 species of plantations were regenerated and the seedling density was 18633 plants / hm2. Castanopsis spp. (2200 plants / hm2) and Glochidion lanceolarium (2183 plants / hm2) were the most regenerated natural forests. Dipterocarpus gracilis (2117 plants / hm2) was the most regenerated plantation, followed by Anogeissus acuminata (2000 plants / hm2). For natural forests, Castanopsis spp had the highest relative density (8.88%), Glochidion lanceolarium had the highest relative frequency (7.36%), Syzygium spp. Had the highest relative abundance (3.79%) and Glochidion lanceolarium had the highest value ( 18.24%). The relative density of Dipterocarpus gracilis was the highest (11.36%), that of Glochidion lanceolarium was highest (9.71%), that of Dipterocarpus gracilis was the highest (5.92%), and that of Glochidion lanceolarium The highest index (23.32%). Dipterocarpus gracilis is common in both natural and plantation seedlings, but the plantation has more seedlings than natural forests. Naturally renewed seedlings are very dense, but due to human disturbance, these newer seedlings usually do not reach the stem-dry stage. Table 4 Reference 35.