College of Food, Ag & Nat Res Sci
This integrated research and extension project aims to lower barriers to establishment of diversified biofuel grassland agroecosystems. Such systems are emerging in importance, because they can function as highly “multifunctional” agroecosystems that provide a variety of ecological services in addition to biofuel production. Unfortunately, establishment of biofuel grasslands is often difficult, unpredictable, and highly vulnerable to interference and invasion by weeds. This group’s preliminary results suggest that interactions with soil microbes may help create these problems, because soil-microbial “legacies” of previous land use can inhibit growth of native grassland species, enabling weed invasion.
One promising option for cost-effective management of this problem is early establishment of "nurse" plant species that directly interfere with weed growth and which appear to change composition and function of soil microbial communities. These researchers propose to address important questions regarding nurse-species effects and weed invasion ecology in diversified grassland agroecosystems. First, do nurse species increase performance of native species relative to invasive species? The researchers use field and glasshouse experiments, and evaluate nurse-species effects relative to effects of a factor of known and strong importance: nitrogen supply. Secondly, do nurse species change microbial composition of soils? The researchers characterize soil microbial populations using 454 and other sequencing and microbiological methods.