Iida Kyohei, Hayasaka Daisuke, Suzuki Yuya, Uchida Taizo, Sawahata Takuo, Hashimoto Koya
Graduate School of Agriculture Kindai University Nara Japan.
Kyushu Branch Regional Environmental Planning Inc. Fukuoka Japan.
Ecol Evol. 2021 Jun 4;11(13):9110-9122. doi: 10.1002/ece3.7755. eCollection 2021 Jul.
Volcanic eruptions are one of the largest natural disturbances and are followed by the establishment of novel plant and animal communities in terrestrial ecosystems. However, the role of pre-eruption vegetation in the establishment of arthropod communities after volcanic disturbances is currently unknown. Here, we asked whether the legacy of pre-eruption vegetation mediates the community structure of ground-dwelling arthropods after volcanic disturbances. The 2015 eruption in Kuchinoerabu-jima Island, southwest Japan, caused two types of disturbances [a pyroclastic flow and a lahar (i.e., mudflow)] in three types of forests (broad-leaved, black pine, and cedar). We hypothesized that pre-eruption vegetation would influence the community structure of ground-dwelling arthropods after the disturbance, and we expected that these effects from vegetation would be more prevalent for the less severe disturbances. The total abundance of ground-dwelling arthropods decreased more in the lahar than the pyroclastic flow, and arthropod species composition showed a greater change after the lahar. These findings suggest that the lahar disturbance was more severe than the pyroclastic disturbance. Contrary to expectations, the difference in the arthropod species composition among the vegetation types was greatest after the lahar. After the pyroclastic flow, leaf litter remained to some degree with all the vegetation types. After the lahar disturbance, however, although the litter in the cedar forests remained, the litter disappeared completely from broad-leaved and black pine forests. The disappearance of litter from these two forest types after the lahar may be responsible for the greater difference in arthropod species composition among the vegetation types. This study shows that the legacy effects of pre-eruption vegetation on terrestrial arthropod communities after volcanic disturbance were different depending on the type of disturbance. Focusing on the role of pre-eruption biotic factors would contribute to a better understanding of the recovery processes of terrestrial ecosystems after large natural disturbances.
火山爆发是最大的自然干扰之一，随后陆地生态系统中会形成新的动植物群落。然而，火山干扰前植被在火山干扰后节肢动物群落建立过程中的作用目前尚不清楚。在此，我们探讨了火山干扰前植被的遗留效应是否会介导火山干扰后地面节肢动物的群落结构。2015年日本西南部口之岛的火山爆发在三种森林类型（阔叶林、黑松林和雪松林）中造成了两种干扰类型[火山碎屑流和火山泥流（即泥石流）]。我们假设火山干扰前的植被会影响干扰后地面节肢动物的群落结构，并且我们预期植被的这些影响在较不严重的干扰中会更为普遍。地面节肢动物的总丰度在火山泥流中的下降幅度比火山碎屑流中更大，并且节肢动物物种组成在火山泥流后变化更大。这些发现表明火山泥流干扰比火山碎屑流干扰更严重。与预期相反，植被类型之间节肢动物物种组成的差异在火山泥流后最大。在火山碎屑流之后，所有植被类型的落叶层都有一定程度的保留。然而，在火山泥流干扰之后，虽然雪松林的落叶层仍然存在，但阔叶林和黑松林的落叶层完全消失了。火山泥流后这两种森林类型落叶层的消失可能是植被类型之间节肢动物物种组成差异更大的原因。这项研究表明，火山干扰前植被对陆地节肢动物群落在火山干扰后的遗留效应因干扰类型而异。关注火山干扰前生物因素的作用将有助于更好地理解大型自然干扰后陆地生态系统的恢复过程。
