GIS and Non-Destructive Sensors for Mapping Soils under Blueberries and Cranberries in New Jersey.
(NE_01-pozdnyakova857938-poster)
Authors:
L. Pozdnyakova* - Rutgers Univ.
P.V. Oudemans - Rutgers Univ.
Abstract:
Sandy soils of Pine Barrens, such as Atsion, Berryland, and Hammonton series (Aeric Haplaquods, Typic Haplaquods, and Aquic Hapludults), are typically used for berry production. There is an increasing awareness among farmers that the spatial variability of soil properties (pH, texture, water content, resistance to penetration, depth to the groundwater) can influence berry yields. However, mapping and measuring most of those properties is technically difficult and time-consuming. Under this research we have utilized state-of-the-art devices designed to measure soil water content (Dynamax Theta Probe), resistance to penetration (Rimik Cone Penetrometer), and electrical resistivity/conductivity (ER/EC) (LandMapper ERM-01) quickly and non-destructively. These devices are suitable for making detailed soil maps of the small to mid-sized farms of New Jersey. Out of three field devices, LandMapper provides information most related to plant growth. Soil electrical resistivity is an auxiliary measure related to soil
physical properties, such as texture and stone content, as well as chemical properties, such as pH, fertilizer state, salinity, and humus content. The LandMapper uses fully customized, interchangeable, and easily constructed four-electrode probes, which allow measuring ER in soil samples, on the walls of soil pits, and during field mapping of soil layers at 0-15 ft depth. All field
measurements using soil sensors were geo-referenced with Trimble PRO-XR and soil samples for pH testing as well as plant samples were collected at the same locations. The results indicate general correspondence of the spatial patterns in soil properties to the SSURGO delineated soil maps for the area. Thus, the soils of Atsion series have the highest ER (up to 10,000 Ohm m), which decreases in a row of Atsion-Berryland-Hammonton-Mullica series. The electrical resistivity may be for the same soil series may be quite different for different farms, but always helped to distinguish between different soil series within a field. In the past, electrical resistivity was measured against soil water content and showed no correlation (r=0.1) at average to high moisture conditions. More repeat measurements at
various soil moistures are needed to develop a reliable scale for soil mapping based
on ER. Recent research on sandy soils of NJ correlated ER with pH (r=0.35), soil texture and resistance to penetration (r=0.5) and generally followed the pre-existing maps of soil series for the areas, but revealed significantly more variability within the soil map units. In addition, some correlations between ER and cranberry yield maps have been observed. Our previous research has shown that ER measurements can also be used to outline soil salinity and stone content, to detect and map
impermeable layers, and to monitor water and fertilizer states in soil. Thus, the new LandMapper ERM-01 can be a valuable tool for fast and economical soil mapping and fertilizer response monitoring for precision agriculture, particularly for
maximizing site yields in berry production.
Speaker Information: Larisa Pozdnyakova, Rutgers Univ., P.E. Marucci Center for Blue/Cranberry Res.& E, Chatsworth, NJ 08019; Phone: 609-726-1590x14; E-mail:
