Collaborative Research: RUI: The influence of ants on regional-scale soil carbon dynamics

土壤有机碳是生态系统的重要属性，影响土壤肥力和全球碳循环。动物已经被证明会影响土壤中的碳，但人们对不同类型的动物最终如何影响决定土壤中碳含量的过程知之甚少。蚂蚁是高度丰富的动物，在世界各地的土壤中筑巢。它们的巢会影响生活在土壤中的细菌和真菌，而这些细菌和真菌又会影响土壤条件，包括碳含量。因此，蚂蚁可能是一个重要的动物群体，影响着决定土壤中碳含量的过程。这项研究促进了我们对生活在土壤中的高度丰富的昆虫动物如何改变和改善生活在蚂蚁巢内或附近的细菌和真菌的条件的理解。在大片地区的许多蚂蚁巢穴中，这些对土壤条件和微生物的影响可能非常大，对于确定土壤中存在多少碳可能是非常重要的。这项研究包括(1)一项受控野外实验，以测试蚂蚁如何影响土壤的物理、化学和生物条件，假想产生影响土壤中碳含量的微生物热点；(2)跨1,550公里的区域样带进行实地调查，以量化蚂蚁巢穴对北美东南部森林和草原土壤条件的影响。该方法允许对因果关系进行测试，以辨别蚂蚁对碳动态和微生物群落的影响的方向性。观测调查有助于估计蚂蚁对碳的影响程度。这种结合的方法为将蚂蚁效应扩展到它们潜在的生态系统、景观和区域意义提供了基础。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Soil organic carbon is an important property of ecosystems that impacts soil fertility and the global carbon cycle. Animals have been shown to affect carbon in soils, but it is poorly understood how different types of animals ultimately affect processes that determine the amount of carbon in soils. Ants are highly abundant animals that nest in soils all over the world. Their nests impact bacteria and fungi living in the soil which, in turn, affect soil conditions including carbon content. Ants may therefore be an important animal group affecting the processes that determine carbon content in soils. This research advances our understanding of how highly abundant insect animals that live in the soil alter and improve conditions for bacteria and fungi that live in or near ant nests. Over many ant nests across large areas, these impacts on soil conditions and microbes may be very large and important for determining, for example, how much carbon is present in soils. The research includes (1) a controlled field experiment to test how ants influence soil physical, chemical, and biological conditions, hypothetically creating microbial hotspots that affect carbon content in soils; and (2) field surveys across a 1,550-km regional transect to quantify ant nest impacts on soil conditions in forests and grasslands in southeastern North America. The approach allows testing of causation to discern the directionality of ant effects on carbon dynamics and microbial communities. The observational surveys facilitate estimates of the magnitude of ant effects on carbon. This combined approach provides the basis for scaling ant effects to their potential ecosystem, landscape, and regional significance.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.