This article highlights the importance of raising soil organic matter in sandy and calcareous soils as it relates to increasing the water holding capacity of the soil. Farming in Florida on sandy soils has numerous limiting factors; one of which is it's low water holding capacity. By raising the soil organic matter content by just 1% can have a significant increase in soil water holding capacity. This would mean that soil would be able to hold more water for long durations. The prospect of increasiong water holding capacity in soils is great for agricultural productivity, and can have a significant impact on water conservation and usage.

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Cattle‐based agriculture on sandy soils has generated concern over P leaching within the basin of Lake Okeechobee, Florida. Elevated P concentrations in surface and groundwater relate to P retention capacity of soils. To evaluate P release and storage capacity of impacted soils with fluctuating water tables, four intact soil cores were analyzed (one upland and three wetland) to determine their maximum sorption capacity (Smax), equilibrium P concentration (EPC0), and soil P storage capacity (SPSC) up to 160‐cm depth. Sorption isotherms were measured for samples at 10‐cm depth increments and data fitted to a Langmuir model (r2 ≥ 0.88). Both EPC0 and water‐soluble P were higher at the surface and decreased with depth. Oxalate‐extractable Fe and Al correlated with (i) oxalate‐extractable P (r2 = 0.83), and (ii) Smax (r2 = 0.71). In situ pore water concentrations collected using multisamplers were consistently higher than EPC0 values. This discrepancy was much greater for near‐surface horizons for which the difference may partially be due to redox‐induced release of P previously scavenged by Fe under anaerobic (flooded) conditions. The SPSC values were positive, however, even when discounting Fe (i.e., assuming in situ chemical reduction) for samples from deeper horizons, suggesting that the small discrepancies for these horizons are not attributable to Fe oxidation. All cores had negative SPSC at the surface and high EPC0, suggesting that neither wetland nor upland soils safely sequester additional P. High pore water P values in the surface horizons are consistent with the inference of the surface soils potentially being a source for P.

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