Soil chemistry and microbial community functional responses to invasive shrub removal in mixed hardwood forests

Reduced soil respiration beneath invasive Rhododendron ponticum persists after cutting and is related to substrate quality rather than microbial community

“…Several factors may have contributed towards this, including the observed increase in solar radiation at ground level post canopy removal, leading to higher soil temperature on cleared plots relative to uncleared plots, known to increase soil respiration (Rutledge et al, 2010;Yuste et al, 2004). Cutting woody shrubs and trees can also cause pulses in rhizodeposition and fine root mortality, which stimulate microbial activity and decomposition beneath the cut shrub (Frank et al, 2018;Pignataro et al, 2012).…”

“…These observed variations in SOM quality may be due to changes in root exudation, canopy cover and litter deposition post-clearance. Whilst shrub clearance can lead to short-term pulses in rhizodeposition (Frank et al, 2018), canopy removal will result in an absence of photosynthesis in cleared plots, and thus lower photosynthate transfer to the soil in the longer-term, relative to uncleared and native vegetation plots. Additionally, carbon substrates are also introduced to the soil from canopy throughfall and in leachates from freshly deposited leaf litter (Frank et al, 2018;Hättenschwiler and Vitousek, 2000).…”

“…Whilst many studies have observed altered decomposition dynamics beneath invasive plants, few have looked at how clearing invaded sites affects soil processes (Frank et al, 2018;Osburn et al, 2018). Recent years have seen a considerable effort to control the spread of invasives such as R.…”

“…A recent study in North America on another invasive shrub, Lonicera maackii (Rupr.) Herder, suggested that cutting leads to a pulse in rhizodeposition (Frank et al, 2018). Increased exudation of carbon substrates post-clearance influences the microbial community, in turn leading to altered SOM degradation (Frank et al, 2018;Pignataro et al, 2012).…”

“…Herder, suggested that cutting leads to a pulse in rhizodeposition (Frank et al, 2018). Increased exudation of carbon substrates post-clearance influences the microbial community, in turn leading to altered SOM degradation (Frank et al, 2018;Pignataro et al, 2012). Despite this, Osburn et al (2018) found that the removal of a Rhododendron maximum canopy had no effect on the activity of enzymes involved in decomposition.…”