Effects of canopy opening and debris deposition on fungal connectivity, phosphorus movement between litter cohorts and mass loss

Responses to canopy loss and debris deposition in a tropical forest ecosystem: Synthesis from an experimental manipulation simulating effects of hurricane disturbance

“…Many agaric decomposer species are sensitive to litter moisture, and the dominant closed canopy species in the LEF (Gymnopus johnstonii) disappeared from litter on exposed ridges after the canopy was opened by Hurricane Hugo (Lodge and Cantrell, 1995). Similarly, Lodge et al (2014) found that in the treatment plots from the CTE, abundances of G. johnstonii in leaf litter differed in the following pattern (most abundant to least abundant): No trim > Trim + debris > Trim + no debris. Very high rates of phosphorus translocation by G. johnstonii (Lodge, 1993), and its great sensitivity to low moisture, suggests that the reduction or loss of this important agaric species from Trim plots is probably at least partly responsible for the increased loss (lack of translocation) of phosphorus from the leaf litter .…”

“…3), and accelerated by debris addition ; a similar finding was observed by González et al (2014) using litter bags, although debris addition only accelerated decomposition in the intact canopy plots and not the Trim + debris plots. A slightly different experimental design used by Lodge et al (2014) relative to that used by González et al (2014) could have accounted for the different decomposition results in the Trim + debris plots; green leaves were placed on top of senesced leaves in the study by Lodge et al (2014) but not in the study by González et al (2014). As expected, decomposition rates were greater for green leaves relative to senescent leaves, and nitrogen and phosphorus concentrations in green leaves were also greater than concentrations in senesced leaves .…”

“…Very high rates of phosphorus translocation by G. johnstonii (Lodge, 1993), and its great sensitivity to low moisture, suggests that the reduction or loss of this important agaric species from Trim plots is probably at least partly responsible for the increased loss (lack of translocation) of phosphorus from the leaf litter . Lodge et al (2014) also suggest that fungal dominance shifts under open canopy conditions, whereby agaric macrofungi decrease and microfungi increase. The increase in microfungi in canopy trimmed plots correlates with increases in Trim plots of groups of litter arthropods that consume microfungi (e.g., mites, collembolans, Psocoptera; Richardson et al, 2010).…”

“…Microbes, decomposition, and biogeochemical attributes Soil and litter microbial communities were evaluated posttreatment from the standpoint of community change and potential for influencing decomposition and nutrient dynamics resulting from CTE treatments González et al, 2014;Lodge et al, 2014). Litter decomposition is mainly driven by microbial activity, but litter substrate, microclimate, and litter arthropods also play an important role (González and Seastedt, 2001;Coleman et al, 2004).…”

“…By observing different cohorts of leaves, including nonsenescent (green) and senescent, Lodge et al (2014) determined that agaric fungi connectivity (an estimate of density) increased with litter moisture and phosphorus concentration, and elevated levels of fungi connectivity was also associated with increased mass loss. In trimmed plots, agaric fungi conserved some phosphorus but much phosphorus from green leaves was leached .…”