Restauración ecológica de bosques tropicales en Costa Rica: efecto de varios modelos en la producción, acumulación y descomposición de hojarasca
Restauración ecológica de bosques tropicales en Costa Rica: efecto de varios modelos en la producción, acumulación y descomposición de hojarasca
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哥斯达黎加热带森林的生态恢复：生产、积累和分解霍哈拉斯卡的各种模型的效果
DOI：
10.15517/rbt.v0i0.3402
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发表时间：
2010
影响因子：
0.6
通讯作者：
Karen D. Holl
中科院分区：
文献类型：
--
作者：
D. Celentano;R. A. Zahawi;B. Finegan;Fernando Casanoves;Rebecca Ostertag;Rebecca J. Cole;Karen D. Holl
热带森林恢复战略有可能加速退化土地养分循环的恢复。凋落物的产生及其分解代表着有机物质和养分向土壤基质的主要转移。我们评估了三种恢复策略下的凋落物产量、在森林地面上的积累及其分解：人工林(整个区域种植树木)、岛屿(种植在三种不同大小的斑块中的树木)和对照(自然更新)样地。我们还比较了幼龄次生林(7-9年生)的恢复策略。2004年6月，在哥斯达黎加南部的六个地点建立了50x50m地块的修复处理。种植的树种包括两种本地用材树种(Terminalia Amazonia和Vochysia guatealens)，间作两种固氮剂(Erythina poeppiana和Inga edulis)。从2008年9月至2009年8月，每隔15天在每个地块内分布的12个0.25m2的落叶陷阱中收集凋落物；2009年2月和5月在每个地块内的四个地点(0.25m2样地)收集积累在土壤表面的凋落物。人工林(6.3 mg/ha)和次生林(7.3 mg/ha)的总凋落物产量没有差异，但高于海岛(3.5 mg/ha)和对照(1.4 mg/ha)。人工林地表凋落物积累量最大(10.6 mg/ha)，与其他处理相比(SF=7.2；I=6.7；C=4.9)。次生林是唯一年凋落物生产量大于土壤表层凋落物累积量的处理。人工林和次生林枯枝落叶层碳储量相似，显著高于其他处理。不同处理间土壤碳浓度和碳储量差异不显著。不同地点之间的凋落物和碳的生产和积累也有很大的变异性。与自然恢复区相比，积极的恢复处理加速了凋落物的产生和碳的储存。然而，在这些条件下，养分循环并不一定得到恢复，因为凋落物在土壤表面的高积累表明分解速度较低，从而减缓了养分返回土壤的速度。
Tropical forest restoration strategies have the potential to accelerate the recovery of the nutrient cycles in degraded lands. Litter production and its decomposition represent the main transfer of organic material and nutrients into the soil substrate. We evaluated litter production, accumulation on the forest floor, and its decomposition under three restoration strategies: plantation (entire area planted with trees), island (trees planted in patches of three different sizes) and control (natural regeneration) plots. We also compared restoration strategies to young secondary forest (7-9 yr). Restoration treatments were established in 50 x 50m plots in June 2004 at six sites in Southern Costa Rica. Planted tree species included two native timber species (Terminalia amazonia and Vochysia guatemalensis) interplanted with two N fixers (Erythrina poeppigiana and Inga edulis). Litter was collected every 15 days between September 2008 and August 2009 in 12 0.25m2 litter traps distributed within each plot; litter that accumulated on the soil surface was collected at four locations (0.25m2 quadrats) within each plot in February and May 2009. Total litter production in plantation (6.3Mg/ha) and secondary forest (7.3Mg/ha) did not differ, but were greater than in islands (3.5Mg/ha) and control (1.4 Mg/ha). Plantation had greatest accumulation of litter on the soil surface (10.6 Mg/ha) as compared to the other treatments (SF = 7.2; I = 6.7; C = 4.9). Secondary forest was the only treatment with a greater annual production of litter than litter accumulation on the soil surface. Carbon storage in litter was similar between plantation and secondary forest, and significantly greater than the other treatments. No differences were found for carbon concentration and storage in the soil among treatments. There was also high variability in the production and accumulation of litter and carbon among sites. Active restoration treatments accelerated the production of litter and carbon storage in comparison to areas under natural recovery. However, the nutrient cycle has not necessarily been restored under these conditions, as high litter accumulation on the soil surface indicates a low decomposition rate, which slows nutrient return to the soil.