Agricultural Practices and Nitrogen Cycling Microbes: The Impact of Sustainable Farming Practices on Nutrient Movement in Indianapolis Urban Farms

As population movement to urban centers and decreased availability of fresh foods becomes more common, the prevalence of food deserts is becoming far greater. Urban farming can potentially help address these issues by bringing healthy and fresh food sources directly to these areas that lack access to quality food. Urban farming is reliant on the implementation of sustainable practices, like the use of cover crops, to increase the amount of nutrients that are accessible to plants from the soil. Nitrogen is a vital nutrient but cannot be readily produced by plants, so it must be obtained by either an external or internal source. The internal supply of Nitrogen is obtained through a mutualistic, commensal, or symbiotic relationship between the plant and nitrogen (N)-cycling microbes found in soil. This study aims to quantify the number of N-cycling microbes that are present in urban farms throughout the city of Indianapolis. These factors indicate that N transformations between different chemical types are occurring within the soil, which will likely affect the immediate and long-term supply of N. This process is essential to increase the health of the soil. The focus of this study is how sustainable farming practices and an increased N supply in the soil can lead to further success in urban farming in Indianapolis, therefore addressing some of the problems of food insecurity impacting many urban centers. It is hypothesized that sustainable practices will increase the amount of N-cycling occurring, making soil healthier for urban farming. I predict that soil samples retrieved from the growing beds of farms that implement sustainable practices will have higher quantity and diversity of N-cycling microbial genes than samples retrieved from outside the growing beds. This study used samples from 4 urban farms in the Indianapolis area. The samples were gathered from inside growing beds and surrounding non-farmed background soil areas. The samples were amplified using Polymerase Chain Reaction (PCR) and then quantified using Quantitative Polymerase Chain Reaction qPCR. Thought there was variability in our results, we found that the samples gathered from inside the growth beds had higher quantity of N-cycling genes than outside the growth beds