Dynamics of hydric soil formation across the edge of a created deep marsh

Abstract

Hydric soils are identified on-site using visible features called "field indicators." It is not known how long it takes for these indicators to form nor whether they occur in created wetlands less than 5-years old. This study evaluated chemical and morphological changes in a created wetland to monitor the development of hydnc soil field indicators over time. A deep marsh, created in 1989, was studied from 1992 through 1994 at the Des Plaines River Wetlands Demonstration Project near Chicago, Illinois, USA, Soil and water samples were collected twice a year from two transects having plots in the following landscape positions: in the marsh, along the marsh edge, in a transition zone to the upland, and in the upland. Detailed profile descriptions were also completed twice per year. In 1994, the soils were classified from the marsh to upland as Typic Endoaquoll, Mollie Endoaquept, Aquic Hapludalf, and Ochreptic Hapludalf. Soil pH values ranged from 7.3 to 7.8 in the upper 15 cm. Carbonates were closest to the surface in the marsh and edge positions. Organic C levels were similar among soils throughout the study at approximately 20 g C/kg soil. Redox potentials and water-table measurements indicated that soil in the marsh and edge positions met the definition of hydric soils throughout the study, while upland positions did not, and soil in the transition positions met the definition in some years. Hydric soil field indicators formed by Fe reduction developed over time in the marsh and edge plots and in some plots of the transition to the upland. The depleted matrix indicator, which formed by the reduction and removal of Fe from the soil matrix, gave the most consistent results for identifying hydric soils. Full development of the indicator in all edge plots was ct~mplete 5 years afler the marsh was constructed. Indicators formed by organic matter accumulation (organic bodies) also developed in the marsh within this period.

Fifteen Years of Vegetation and Soil Development after Brackish‐Water Marsh Creation

“…Our findings indicate that within the created marsh, wetland soil development proceeds at different rates, with reducing conditions and wetland soil characteristics developing more rapidly at low elevations that are inundated longer than at high elevations that are inundated less frequently and for shorter periods. Similar to our study, reducing conditions and wetland soil characteristics (depleted matrix) developed more rapidly in the interior of a created freshwater marsh as compared with the marsh‐upland transition zone (Vepraskas et al 1999). Five years after creation, the interior of the freshwater marsh contained depleted soil matrix, evidence of Fe reduction and leaching, and as development of an organic soil layer (Vepraskas et al 1999).…”

“…Similar to our study, reducing conditions and wetland soil characteristics (depleted matrix) developed more rapidly in the interior of a created freshwater marsh as compared with the marsh‐upland transition zone (Vepraskas et al 1999). Five years after creation, the interior of the freshwater marsh contained depleted soil matrix, evidence of Fe reduction and leaching, and as development of an organic soil layer (Vepraskas et al 1999).…”

Phosphorus mobilization in rewetted peat and sand at variable flow rate and redox regimes

“…The Eh resulting from the influent O 2 supply reflects both the combined effect of differences in mobile flow volume and also the inherent microbial activity in the sand and peat. Generally, microbial activity increases with increasing carbon content (Vepraskas et al, 1999), thus an inherent lower microbial activity is expected in the sand Table 2 Accumulated total P and Fe (mg) leached from the sand and peat soils given both after percolation of 5500 cm 3 and 20 pore volumes (PV).…”

Impacts of hydraulic fracturing development on macroinvertebrate biodiversity and gill morphology of net-spinning caddisfly (Hydropsychidae,Diplectrona)in northwestern Pennsylvania, USA

“…Percent hydric soils were found to be correlated with gill width at a 90% confidence level (r D 0.73, p D 0.099). Hydric soils are known to create anaerobic conditions (similar to those found in wetlands) in the upper layers of the soils (Vepraskas et al 1999), presumably lowering in-stream DO levels. We believe our findings indicate that gill widths were driven by DO, but the amount of hydric soils was a better long-term indicator of stream DO levels as seasonal fluctuations of DO can be considerable (Jamshidi & Bakar 2011).…”