Sikes Microbial Lab​
Fire-microbial-plant feedbacks in pyrogenic ecosystems
​A major research effort in our lab focuses on how repeated fires can alter the structure and function of soil microbial communities, then how changes in these functions can alter fuels in a way that feeds back to future fires. The project is funded by an NSF grant and in collaboration with Dr. Bill Platt at LSU. The work largely focuses on pine savannas in the SouthEast USA and includes next generation sequencing of microbes in soil and litter, litter bag experiments to measure decomposition changes after fire, and greenhouse experiments to see how fire impacted soil microbes alter fuel production by plants. Data so far show that fire shifts fungal and bacterial communities, and microbial decomposition of new litter slows after fire by ~40%. The consequence is that more fuels should buildup and increase the likelihood of new fires (a positive feedback).
Maximizing perennial crop diversity, soil management, and soil microbes in sustainable agriculture
This project explores how soil microbial communities vary with changing plant diversity and soil management in agroecosystems, then connects how these soil microbial changes feedback to alter perennial crop productivity. The project has several field and greenhouse experiments including: 1) Characterize soil communities in long term field plots in annual agriculture, perennial agriculture, or restored prairie 2) Determine how soil biota from these plots alter perennial crop growth and 3) setup a new long term field experiment to separate the effects of tillage, plant identity, and diversity on soil microbial feedbacks (pathogens and mutualists. This work is a collaboration with the Land Institute's Perennial Agricultural Project. It is led by Tom McKenna in collboration with Tim Crews at the Land Institute.
Interactive effects of rainfall, soil microbes, and ecotype on plant fitness
This project utilizes the amazing rainfall gradient across Kansas to ask whether a flowering and fitness of non-native plant is affected more strongly by microbes depending on the drought stress, the host plant's origin, or the origin of the soil microbial community. We the biennial Verbascum thapsus (common mullen) as a model system. The work sets the stage for developing research on stress stabilization of mutualisms and two new grants looking at interactions between rainfall/drought and plant microbiomes. Early data suggest that ecotype can have a strong effect on the timing of flowering and plant height. Ecotype and watering interactively affect rosette site before flowering, with smaller effect based on the origin of microbial inoculum.
Prairie Monoliths as tools for restoration and tests of ecosystem nucleation
​A portion of a pristine prairie managed by the Kansas Biological Survey is slated to be destroyed as a result of road widening. We experimentally moved more than 200 large chunks of prairie ("monoliths") with a tree spade. Each prairie monolith is an intact ecosystem (~1.2m wide and ~1m deep) that has been relocated to either a recently tilled filled, an old field abandoned for more than 15 years, or a targeted site with active restoration for the past 10 years. In those site, we have two main experiments. The first simply compares how plants and microbes move in and out of a prairie monolith versus a monolith of the background site. The second uses six monoliths clustered to different degrees to determine how monolith area can influence their inertia to spread, resist invasion, and facilitate the planting of native prairie plants nearby.
Feedbacks between social and ecological connectivity through management surrounding national parks
​This is a large scale collboration looking at the Coupled Dynamics of Natural and Human Systems, funded by NSF. Major protected areas like National Parks are surrounded by land managed by other entities including the Forest Service, Tribes, the Bureau of Land Management, State and Local Agencies, as well as Private Citizens. Ecological connectivity such as fires and invasive species might promote collaboration among these entities. From the social side, managers that talk and collaborate more might promote similar kinds of ecology between their properties. This work explores the feedbacks between management and ecology in 5 national parks, and our lab focuses on measuring soils.
Microbiomes of Aquatic, Plant and Soil Systems Across Kansas
Microbiomes are critical components of ecosystem functions and knowledge of them is necessary to feed our growing population, sustain agriculture, maintain soil quality, and minimize greenhouse gases and water contaminants. This project focuses on the function, dynamics, and connectivity of Microbiomes of Aquatic habitats, Plants, and Soils (MAPS). This large scale project is funded by the EPSCoR program to create an observational and experimental network across the strong precipitation gradient in agriculturally-dominated Kansas, using both agricultural and native sites. Scales range from genes to ecosystems and across habitats (terrestrial to aquatic), with the goal to illuminate how MAPS can be invoked to enhance productivity, mitigate environmental problems in agriculturally-dominated landscapes, and conserve native grasslands and their ecosystem functions. We specifically aim to quantify how climate and land-use legacies govern MAPS as a means of predicting the resistance and resilience of multiple ecosystem properties to long-term (e.g. contemporary climate change) and punctuated (e.g. extreme climate events, land use changes) perturbations.
Microbe eco-evolutionary feedbacks as
drivers of plant coexistence and diversity gradients
Understanding the causes and consequences of biodiversity is critical to predicting environmental trajectories in a rapidly changing world. Accumulated evidence supports a central role of pathogens in the maintenance of plant diversity, however the potential role of plant pathogens in generating patterns of biodiversity and the benefits of biodiversity are poorly understood. This project tests if eco-evolutionary feedbacks between plants and pathogens are major drivers of plant coexistence, diversity, and the productivity benefits of diversity. It uses an integrated set of field observations, field manipulations and greenhouse assays, performed on parallel diversity and rainfall gradients in North American and Asian grasslands. We couple our experimental tests of plant phylogenetic diversity with patterns of plant resistance genes that likely mediate eco-evolutionary feedback strength. The project is led by Jim Bever (KU) and includes other KU researchers, those at Minnesota and Illinois State, and an entire team in China for the complementary Asian steppe experiment.