Characterizing and mapping the soil spatial variability of USDA-Subtropical Horticulture Research Station (SHRS), Miami, FL: A significant research endeavor

Authors: BHASKAR, MARUTHI SRIDHAR - Florida International University; Nageswara Rao, Madhugiri; SHETTY, KATEEL - Florida International University; JAYACHANDRAN, KRISHNASWAMY - Florida International University; Singh, Sukhwinder

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2024
Publication Date: 11/10/2024
Citation: Bhaskar, M., Nageswara Rao, M., Shetty, K., Jayachandran, K., Singh, S. 2024. Characterizing and mapping the soil spatial variability of USDA-Subtropical Horticulture Research Station (SHRS), Miami, FL: A significant research endeavor. Meeting Abstract, 2024 ASA,CSSA,SSSA International Annual Meeting, November 10-13, 2024. San Antonio, Texas.

Interpretive Summary:

Technical Abstract: Title: Characterizing and Mapping the Soil Spatial Variability of USDA- Subtropical Horticulture Research Station (SHRS), Miami, FL: A Significant Research Endeavor Abstract: The identification and assessment of soil fertility status, along with the mapping of their spatial distribution, play a crucial role in sustainable agricultural resource management. This research is a collaborative research effort between USDA-ARS and Florida International University to examine the spatial variability of soil quality parameters in USDA-Subtropical Horticulture Research Station, Miami, FL. The SHRS is one of the oldest research stations in the USDA-National Plant Germplasm System. Over the past 100 years, SHRS has collected plant germplasm from 800 unique plant species spanning 350 genera. This collection includes more than 9,000 individual plants distributed across over 220 acres in diverse geographical conditions. The objectives of this study are as follows: 1) To determine how soil quality properties vary spatially across the research station, 2) To identify differences between various plant growing practices and landscape parameters that may substantially contribute to soil spatial variation, and 3) To analyze geospatial data to map the nature and pattern of soil nutrient availability and plant productivity. Field investigations were carried-out during the summer of 2024. A total of 246 grid-based soil samples were collected at a depth of 0-20 cm using a soil sampling auger. Geo-referenced soil samples were air-dried, sieved, and analyzed for various nutrients and heavy metal concentrations using a handheld XRF analyzer. Spatial interpolation models were developed and analyzed to monitor and map the spatial variation of soil fertility. There were significant spatial trends in the soil concentration of P, Ca, Al, and Mg, all showing an increasing trend from west to east. No significant spatial trend was observed in the soil concentrations of Si, S, and K. However, the Fe concentrations in soil showed an increasing trend from north to south. Among the heavy metals, the soil concentrations of Cr, Mn, Co, Cu, Zn, As, Sr, and Pb generally remained low with regional spikes, while Ni concentrations showed an increasing trend from west to east. These results demonstrate how landscape management, topography, drainage, and plant growth factors can influence the spatial trends of soil fertility. Therefore, our research findings will be instrumental in the development and improvement of the best spatially variable, site-specific farm management practices to enhance agricultural production and the environmental sustainability.