Drivers of the population dynamics of a tropical ecosystem engineer

热带物种种群动态的驱动因素还不是很清楚，尤其是昆虫。气候变化通常被认为对昆虫的影响不同于脊椎动物，但数据稀缺。因此，重要的是更多地关注昆虫，特别是当它们提供关键的生态系统服务时。堆筑白蚁是热带生态系统的重要生态工程，对维持物种多样性和提供生态系统服务至关重要。真菌白蚁大白蚁是西非稀树大草原上主要和最重要的土丘建筑白蚁种类。30年来，我们一直在象牙海岸的科莫国家公园研究这种物种，包括长期的种群调查。这些数据揭示了该物种最近的戏剧性下降，可能与气候变化有关。在拟议的项目中，我们将确定这种关键昆虫从当地到区域规模的种群动态的驱动因素。为此，我们将使用我们独特的长期数据集，并以更详细的研究加以补充。这将使我们能够测试明确的假设，理清各种因素的相对重要性，并确定潜在的机制。此外，我们将测试与气候变化相关的降雨模式的变化是否以及在多大程度上导致了最近嗜血分枝杆菌的减少。因此，我们的研究将全面了解形成无脊椎动物生态系统工程师种群动态的过程，这对维持热带物种多样性至关重要，其丰度最近以惊人的速度下降。

Drivers of population dynamics of species in the tropics are not well understood, especially for insects. Climate change is often supposed to affect insects differently than vertebrates but data are scarce. Thus, it is important to focus more on insects, especially when they provide crucial ecosystem services. Mound-building termite species are important ecosystem engineers of tropical ecosystems, which are essential for maintaining species diversity and providing ecosystem services. The fungus-growing termite Macrotermes bellicosus is the major and most important mound-building termite species in West-African savannahs. We are studying this species in the Comoé National Park of Ivory Coast since 30 years, including long-term population surveys. These data reveal a recent and dramatic decline of the species, potentially related to climate change. In the proposed project, we will identify the drivers of the population dynamics of this crucial insect from the local to the regional scale. To this end, we will use our unique long-term data set and complement it with more detailed studies. This will allow us to test explicit hypotheses, disentangle the relative importance of various factors, and identify underlying mechanisms. In addition, we will test whether and to which degree climate-change-associated alterations of rainfall patterns account for the recent decline of M. bellicosus. Thus, our study will provide a comprehensive understanding of the processes shaping the population dynamics of an invertebrate ecosystem engineer that is essential for maintaining tropical species diversity and whose abundance recently dropped at an alarming rate.