Influence of environmental parameters on litter decomposition in wetlands in West Virginia, USA

Abstract

Plant litter decomposition varies by species and environmental conditions. To study environmental controls of decomposition, we measured plant litter decomposition rates in six wetlands located in West Virginia, USA. Four common wetland litter species were used: broadleaf cattail (Typha latifolia L.), common rush (Juncus effusus L.), brookside alder (Alnus serrulata (Ait.) Willd.), and reed canary grass (Phalaris arundinacea L.). A fifth litter type was created from a mix of common rush, brookside alder, and reed canary grass. Litter bags were collected over two years, from December 2007 to December 2009, and environmental variables near litter bags were measured every two weeks. Nine environmental parameters and one study parameter were then used to construct and test the ability of 22 a-priori models to predict the decomposition rate of each litter type. The environmental variables that most influenced and, therefore, best predicted decomposition rate varied among litter types. Brookside alder decomposition rate was best predicted by soil temperature (ST), water pH (WPH), and the number of transitions between flooded and exposed conditions (FET); reed canary grass decomposition rate was best predicted by air temperature (AT), WPH, and ST; common rush decomposition rates were best predicted by AT; broadleaf cattail decomposition rate was best predicted by hydroperiod (HP) and FET; and the mixed litter decomposition rate was best predicted by AT and WPH. Overall, AT, ST, and WPH were directly related to decomposition rate, while HP was inversely related. The FET was directly related to decomposition rates of common rush and broadleaf cattail and inversely related to the decomposition rate of brookside alder. The study of litter decomposition helps reveal the link between environmental conditions and wetland function.

Non-additive effects of water availability and litter quality on decomposition of litter mixtures

“…where W 0 is the initial litter mass and W t is the mass remaining at time t in days (Olson 1963;Gingerich et al 2014). Mass remaining was calculated as a percentage of the initial mass.…”

Comparison of ecosystem processes in a woodland and prairie pond with different hydroperiods

“…While climate change will influence both water temperature and hydroperiod (Ali et al 2016), Brooks (2009) indicated that the duration (hydroperiod) and the timing (hydroregime) of inundation are the major abiotic factors influencing small ponds. Hydroperiod has been shown to have significant impacts on benthic and zooplankton community structure (Pyke 2005;Kneitel 2014), food chain length (Schriever and Williams 2013) leaf litter breakdown (Gingerich et al 2014) and breeding success of amphibians (Chandler et al 2016). As Bauder (2005) points out, the variability in the hydrology of individual ponds and the variety of hydrological conditions likely means that systems will need individual consideration to be conserved, managed or restored.…”

Decomposition of Three Common Moist-Soil Managed Wetland Plant Species

“…Considerable attention has focused on how inundation regimes (e.g., hydroperiods) drive litter decomposition (Brinson et al 1981;Neckles and Neill 1994;Gingerich et al 2014), because water directly influences decomposition via leaching and soil moisture, but also indirectly by influencing environmental conditions (e.g., pH, temperature, oxygen levels, and dissolved nutrient availability) that affect microbial activity (Mitch and Gosselink 1993;Kuehn and Suberkropp 1998;Lan et al 2006). Beyond inundation duration, many studies of wetland plant litter decomposition have focused on herbaceous perennial species (Bell et al 1978;Neckles and Neill 1994;Wrubleski et al 1997), rather than on annual species (Anderson and Smith 2002), which tend to have less structural complexity and lignin and shorter decomposition time (Brinson et al 1981;Ruppel et al 2004;Poi de Neiff et al 2006).…”

“…Beyond inundation duration, many studies of wetland plant litter decomposition have focused on herbaceous perennial species (Bell et al 1978;Neckles and Neill 1994;Wrubleski et al 1997), rather than on annual species (Anderson and Smith 2002), which tend to have less structural complexity and lignin and shorter decomposition time (Brinson et al 1981;Ruppel et al 2004;Poi de Neiff et al 2006). Consequently, the impact of inundation regimes on decomposition rates is complicated because of variability in conditions other than inundation duration (Brinson et al 1981;Neckles and Neill 1994;Fuell et al 2013;Gingerich et al 2014).…”