FROM DRONES TO SOIL CORES: COMPREHENSIVE ECOLOGICAL ASSESSMENTS FOR ENHANCING CONSERVATION MANAGEMENT OF URBAN FORESTED NATURAL AREAS

Urban natural areas are vegetated areas within cities that exhibit characteristics of non-urban natural areas in that they have relatively high levels of self-regulation (low or no level of management) of natural ecosystem processes and exhibit high taxonomic, genetic, and structural diversity. When these areas take the form of urban parkland, they are often managed for their social benefits to urban residents, while their ecological potential remains underutilized. Growing interest in enhancing biodiversity conservation in cities has highlighted the importance of improving the ecological planning and management of urban natural areas, particularly forested natural areas. For the variety of agencies and non-profit organizations governing and managing urban natural areas, achieving conservation goals relies on comprehensive ecological data, but this information is often lacking in spatial resolution or altogether absent in most city parks and recreation departments across the U.S. Acquiring necessary data depends on extensive and time-consuming ground surveys, where city budgets and time constraints can present considerable obstacles. With over 2,000 acres of urban natural areas, government agencies and nonprofits in Knoxville, Tennessee are facing these same obstacles. The objectives of this research study were to 1) use drone remote sensing and traditional ecological field methods to quantify and characterize key indicators of urban forest health (vegetation, soils, and ecological impacts) of a 42-acre parcel of urban forested area in Knoxville, Tennessee, 2) investigate statistical relationships between forest health indicators and 4 vegetation indices derived from drone imagery to assess (“ground-truth”) a novel drone application in urban forest conservation management, and 3) investigate statistical relationships between forest health indicators and soil physical, textural, and chemical attributes. Key findings of the comprehensive ecological assessment reveal the dominance of 129 native plant species, invasion by 11 non-native plant species, acidic high-carbon soils sufficient in most plant available macro- and micro- nutrients, and significant relationships between both drone vegetation indices and soil attributes and key indicators of urban forest health. Findings from this study establish necessary baseline ecological and soils data and demonstrate a novel application of drone remote sensing in the conservation management of an urban forested natural area.