Soil sulfur supply assessment using anion exchange resin strip-Plant Root Simulator™ probe
Li, S., B. Lin and W. Zhou. 2001. Communications in Soil Science and Plant Analysis 32:711-722
Abstract
A new soil test method for determining soil available sulfur (S) using an anion exchange resin strip, a specially pretreated anion exchange membrane encased in a plastic applicator - Plant Root Simulator (PRS™)-probe, was evaluated. Samples of 18 China soils were collected from the 0 - 20 cm layer, dried, sieved, and analyzed for available S using four chemical extracting solutions: 0.01 mol calcium chloride (CaCl2) L-1, 0.01 mol calcium dihydrogen phosphate [Ca(H2PO4)2] L-1, 0.016 mol potassium dihydrogen phosphate (KH2PO4) L-1, and 0.5 mol sodium bicarbonate (NaHCO3) L-1 (pH 8.5). Available S in soils was also extracted by a resin strip method with 24-hour and 2-week burial times. Pot experiments were conducted to compare plant response to determined soil available S. Results showed that soil-available S extracted by the resin strips at 24 hour and 2 week burial times was significantly correlated with S extracted by the chemical methods, especially highly and significantly correlated with available S by 0.01 mol Ca(H2PO4)2 L-1 (r2 = 0.725*** and r2 = 0.600***) and 0.016 mol KH2PO4 L-1 (r2 = 0.706*** and r2 = 0.540***), respectively. Results also showed significant correlation between S availability by the resin strips at the two burial times and plant S uptake (r2 = 0.594***, r2 = 0.401** for corn and r2 = 0.773***, r2 = 0.546*** for rice). Furthermore, results showed significant correlation between determined S by the resin strip at the 24 hour burial time and relative dry matter yield for corn (r2 = 0.494**) and rice (r2 = 0.687***), respectively. An anion exchange resin strip was found to be a suitable alternative method in the evaluation of S bioavailability in soils.
