Effective management of Japanese black pine (Pinus thunbergii Parlat.) coastal forests considering tsunami mitigation
Effective management of Japanese black pine (Pinus thunbergii Parlat.) coastal forests considering tsunami mitigation
复制标题
考虑减缓海啸对日本黑松 (Pinus thunbergii Parlat.) 沿海森林的有效管理
DOI：
10.1016/j.jenvman.2022.114754
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发表时间：
2022
影响因子：
8.7
通讯作者：
NorioTanaka
中科院分区：
文献类型：
--
作者：
Hiroyuki Torita;Yoshiya;Igarashi;NorioTanaka
人们认识到，沿海森林可大大减少海啸的能量，并可作为抵御海啸的措施。然而，由于海啸而折断的树木会产生木质碎片，并对人和建筑物造成二次损害。因此，沿海森林对海啸和人类既有积极的影响，也有消极的影响。为了阐明这些影响和森林经营之间的关系，在这项研究中，三个实验森林经营类型被认为是：稀疏型（ST：0.6？Ry = 0.7）、中间型（MT：0.8？Ry ≥ 0.9）和密植型（DT：未间伐），其中Ry为相对产量指数。此外，对所考虑的森林类型进行了数值模拟。流体力减少的效果取决于林分的生长阶段和海啸造成的森林破坏的发生。对于5米的海啸高度，DT和ST表现出最高和最低的有效性，在减少流体力，分别。然而，当海啸高度超过15米，三种管理类型表现出几乎相同的效果，在减少流体力。此外，随着海啸高度的增加，树木的损害也增加。在海啸高度大于或等于15米的情况下，所有管理类型下的所有树木都受到损坏。树木的破坏形式包括树木倾覆和树干折断。MT和ST的树体损伤模式仅为倾覆，DT则表现为倾覆和树干断裂的组合。因此，对于防止树干断裂，ST和MT比DT更合适。因此，针对海啸的森林管理应考虑到每个区域的估计海啸高度。
Coastal forests have been recognized to considerably reduce the energy of tsunamis and act as a measure against them. However, broken trees due to tsunamis produce woody debris and cause secondary damage to people and buildings. Thus, coastal forests have both positive and negative effects on tsunamis and people. To elucidate the relationships between these effects and forest management, three experimental forest management types were considered in this study: the sparse type (ST: 0.6 ?Ry≦ 0.7), middle type (MT: 0.8 ?Ry≦ 0.9), and dense type (DT: unthinned), whereRyis the relative yield index. In addition, numerical simulations were performed for the forest types considered. The effect of fluid force reduction depended on the growth stage of the forest stands and the occurrence of forest damage caused by the tsunami. For a tsunami height of 5 m,DTandSTexhibited the highest and lowest effectiveness in reducing the fluid force, respectively. However, when the tsunami height exceeded 15 m, the three management types exhibited almost the same effectiveness in reducing the fluid force. Moreover, tree damage increased with an increase in the tsunami height. All trees were damaged under all management types for a tsunami height greater than or equal to 15 m. Modes of tree damage included tree overturning and trunk breakage. The modes of tree damage forMTandSTwere overturning only, andDTexhibited a combination of overturning and trunk breakage. Therefore,STandMTare more suitable thanDTfor preventing trunk breakage. Thus, forest management against tsunamis should take estimated tsunami height into account for each region.