Asefa Addisu, Reuber Victoria, Miehe Georg, Wraase Luise, Wube Tilaye, Schabo Dana G, Farwig Nina
Department of Biology, Conservation Ecology Philipps-Universität Marburg Marburg Germany.
Department of Geography, Vegetation Geography Philipps-Universität Marburg Marburg Germany.
Ecol Evol. 2023 Jul 17;13(7):e10337. doi: 10.1002/ece3.10337. eCollection 2023 Jul.
Human activities, directly and indirectly, impact ecological engineering activities of subterranean rodents. As engineering activities of burrowing rodents are affected by, and reciprocally affect vegetation cover via feeding, burrowing and mound building, human influence such as settlements and livestock grazing, could have cascading effects on biodiversity and ecosystem processes such as bioturbation. However, there is limited understanding of the relationship between human activities and burrowing rodents. The aim of this study was therefore to understand how human activities influence the ecological engineering activity of the giant root-rat (), a subterranean rodent species endemic to the Afroalpine ecosystem of the Bale Mountains of Ethiopia. We collected data on human impact, burrowing activity and vegetation during February and March of 2021. Using path analysis, we tested (1) direct effects of human settlement on the patterns of livestock grazing intensity, (2) direct and indirect impacts of humans and livestock grazing intensity on the root-rat burrow density and (3) whether human settlement and livestock grazing influence the effects of giant root-rat burrow density on vegetation and vice versa. We found lower levels of livestock grazing intensity further from human settlement than in its proximity. We also found a significantly increased giant root-rat burrow density with increasing livestock grazing intensity. Seasonal settlement and livestock grazing intensity had an indirect negative and positive effect on giant root-rat burrow density, respectively, both via vegetation cover. Analysing the reciprocal effects of giant root-rat on vegetation, we found a significantly decreased vegetation cover with increasing density of giant root-rat burrows, and indirectly with increasing livestock grazing intensity via giant root-rat burrow density. Our results demonstrate that giant root-rats play a synanthropic engineering role that affects vegetation structure and ecosystem processes.
人类活动直接或间接地影响着地下啮齿动物的生态工程活动。由于穴居啮齿动物的工程活动受到植被覆盖的影响，并通过觅食、挖掘洞穴和堆积土丘等活动反过来影响植被覆盖，人类活动（如定居点和牲畜放牧）可能会对生物多样性和生物扰动等生态系统过程产生连锁反应。然而，人们对人类活动与穴居啮齿动物之间的关系了解有限。因此，本研究的目的是了解人类活动如何影响巨根鼠（）的生态工程活动，巨根鼠是埃塞俄比亚巴勒山脉非洲高山生态系统特有的一种地下啮齿动物。我们在2021年2月和3月收集了关于人类影响、挖掘活动和植被的数据。通过路径分析，我们测试了：（1）人类定居点对牲畜放牧强度模式的直接影响；（2）人类和牲畜放牧强度对巨根鼠洞穴密度的直接和间接影响；（3）人类定居点和牲畜放牧是否会影响巨根鼠洞穴密度对植被的影响，反之亦然。我们发现，离人类定居点较远的地方牲畜放牧强度低于其附近地区。我们还发现，随着牲畜放牧强度的增加，巨根鼠的洞穴密度显著增加。季节性定居点和牲畜放牧强度分别通过植被覆盖对巨根鼠洞穴密度产生间接的负面影响和正面影响。在分析巨根鼠对植被的相互影响时，我们发现随着巨根鼠洞穴密度的增加，植被覆盖显著减少，并且通过巨根鼠洞穴密度间接随着牲畜放牧强度的增加而减少。我们的研究结果表明，巨根鼠发挥着一种伴人工程作用，影响着植被结构和生态系统过程。
