CAJ | 학술논문

在孟加拉吉大港丘陵地区,调查了热带季风气候条件下的3种人工林(7年生大叶相思(Acacia auriculiformis)林、15年生大叶相思林和18年生混交林)和1种天然林的森林凋落物及其对土壤性质的作用.结果表明,总的有机质积累随人工林树龄增加而增加,但是年积累量随之降低.在同一植被类型内,不同坡位新鲜或部分分解的凋落物有机质累计量变化较大,坡底部有机质积累量最高,沿着山坡向上逐渐减少.在15年生大叶相思人工林内,土壤整合有机物积累量变化趋势与新鲜或部分分解有机质积累量变化趋势相反.在7年生和15年生的大叶相思林以及18年龄的阔叶混交人工林内,新鲜、部分分解和完全分解(含土壤整合有机质)有机质总生产速率分别是2554.31、705.79和1028.01kg.ha-1·a-1,新鲜凋落物有机质在3种林分中的生产速率分别是38.23,19.40和30.48 kg·ha-1·a-1.3种人工林和自然林内,平均新鲜凋落物的有机质积累占有机质产出总量的32.45%,部分分解凋落物占13.50%,而全分解整合土壤有机质占54.56%.森林土壤酸度随凋落物分解阶段的深入而增加.
재맹가랍길대항구릉지구,조사료열대계풍기후조건하적3충인공림(7년생대협상사(Acacia auriculiformis)림、15년생대협상사림화18년생혼교림)화1충천연림적삼림조락물급기대토양성질적작용.결과표명,총적유궤질적루수인공림수령증가이증가,단시년적루량수지강저.재동일식피류형내,불동파위신선혹부분분해적조락물유궤질루계량변화교대,파저부유궤질적루량최고,연착산파향상축점감소.재15년생대협상사인공림내,토양정합유궤물적루량변화추세여신선혹부분분해유궤질적루량변화추세상반.재7년생화15년생적대협상사림이급18년령적활협혼교인공림내,신선、부분분해화완전분해(함토양정합유궤질)유궤질총생산속솔분별시2554.31、705.79화1028.01kg.ha-1·a-1,신선조락물유궤질재3충림분중적생산속솔분별시38.23,19.40화30.48 kg·ha-1·a-1.3충인공림화자연림내,평균신선조락물적유궤질적루점유궤질산출총량적32.45%,부분분해조락물점13.50%,이전분해정합토양유궤질점54.56%.삼림토양산도수조락물분해계단적심입이증가.
Litter fall and its effect on forest soil properties at each decomposition stages were investigated in tropical monsoon climatic con-ditions of three plantations (7-year acacia plantation, 15-year acacia plantation and 18-year mixed plantation) and one natural forest (Si-tapahar forest) from Chittagong hilly region of Bangladesh. Results showed that total accumulation of organic matter increased with planta-tion age, accompanying with a decrease of annual accumulation rate. Within the same vegetation type, the organic accumulation of both fresh and partially decomposed litter with humus varied significantly (/,5_0.05) on hill positions, being highest on bottom slone and de-creased gradually towards hilltop in the forest. Reverse trend in accumulation of soil organic matters was shown in 15-year Acacia auriculi-formis plantation, from where fuel wood collected. In 7- and 15-year acacia and 18-year mixed broadleaved plantations, rates of total or-ganic matter production consisting of flesh, partially and completely decomposed litter as well as incorporated organic matter in soil were litter with humus 13.50% and incorporated organic matter in soil 54.56% of the total organic matter production with mean litter thickness of 0.90 cm. Soil acidity increased with the increase of decomposition stage of organic matter.