Linking Termite Feeding Preferences and Soil Physical Functioning in Southern-Indian Woodlands

Abstract

Termites are undoubtedly amongst the most important soil macroinvertebrate decomposers in semi-arid environments in India. However, in this specific type of environment, the influence of termite foraging activity on soil functioning remains unexplored. Therefore, this study examines the link between the quality of litter and the functional impact of termite feeding preferences on soil properties and soil hydraulic conductivity in a deciduous forest in southern India. Different organic resources (elephant dung: “ED”, elephant grass: “EG”, acacia leaves: “AL” and layers of cardboard: “CB”) were applied on repacked soil cores. ED appeared to be the most attractive resource to Odontotermes obesus, leading to a larger amount of soil sheeting (i.e., the soil used by termites for covering the litter they consume), more numerous and larger holes in the ground and a lower soil bulk density. As a consequence, ED increased the soil hydraulic conductivity (4-fold) compared with the control soil. Thus, this study highlights that the more O. obesus prefers a substrate, the more this species impacts soil dynamics and water infiltration in the soil. This study also shows that ED can be used as an efficient substrate for accelerating the infiltration of water in southern-Indian soils, mainly through the production of galleries that are open on the soil surface, offering new perspectives on termite management in this environment.

The distribution of Silicon in soil is influenced by termite bioturbation in South Indian forest soils

“…The presence of grass phytoliths in TM therefore suggests that termites act as primary decomposers of herbivore dungs in the studied area. This hypothesis is in line with recent studies carried out in southern India which showed that elephant dung material is very attractive to termites which prefer this material over carton, wood or leaves (Cheik et al, 2018(Cheik et al, , 2019Shanbhag et al, 2019). Indeed, despite inhabiting forested environments in Karnataka and the Nilgiri Region, elephants preferentially feed on Panicoideae grasses which constitute more than 84% of their annual bulk diet (Baskaran et al 2010).…”

“…Despite the fact that O. obesus can feed on a variety of litter components (e.g. elephant dung, wood and leaves) (Cheik et al, 2018(Cheik et al, , 2019Shanbhag et al, 2019), grasses are mostly consumed by herbivores in Mule Hole catchment. The presence of grass phytoliths in TM therefore suggests that termites act as primary decomposers of herbivore dungs in the studied area.…”

Effects of termites growth on litter decomposition: a modeling approach

“…The decomposition of plant material is carried out primarily by termites by their partial digestion and fragmentation of organic matter or dragging litter into the soil (Bender et al 2016). After gut transit, organic matter may be either readily available or less available for decomposition (Bradford et al 2017;Cheik et al 2019). Hence, termites participate actively in the process of bioturbation through their influences on organic matter dynamic and despite their small size, termites can largely contribute to total soil faunal biomass (Jouquet et al 2011).…”

Termite footprints in restored versus degraded agrosystems in South West Niger

“…Their role in ecosystems has been reviewed by several authors (de Bruyn & Conacher, 1990;Sithole, Magwaza, Mafongoya, & Guy, 2018). In arid and semi-arid regions, termites are the key soil turbators all year round, strongly influencing SOM turnover and soil structure in agrosystems (Abe, Bignell, & Higashi, 2000;Lal, 2015;Cheik, Shanbhag et al, 2019). By constructing networks of foraging tunnels, they alter soil water infiltration and soil aeration (Colloff, Pullen, & Cunningham, 2010;Lal, 2015).…”