Soil macrofauna in relation to soil and leaf litter properties in tree plantations

Abstract

Soil communities exert strong influences on the processing of organic matter and nutrients. Plantations of trees, especially of nitrogen fixing ones, may affect the soil macrofauna through litter quality and quantity. This study was conducted in a randomized block design with three blocks consisting of Populus euphratica, Eucalyptus camaldulensis, Eucalyptus microtheca, Acacia farnesiana, Acacia salicina, Acacia saligna, Acacia stenophylla and Dalbergia sissoo monoculture plantations that were established in 1992. Soils and soil macrofauna were sampled in November 2006. Leaf litterfall was collected from November 2006 to November 2007 at bi-weekly intervals. Macroinvertebrate abundance and biomass were consistently higher in A. salicina plantations than in the others, whereas they were lowest in E. camaldulensis. Tree species and nitrogen fixing trees significantly influenced the soil macrofauna richness. The results suggest that the earthworm distribution is regulated by leaf litter quality (Ca, C and N) whereas the macrofauna richness is regulated by leaf litter mass, soil organic carbon and leaf litter Mg. Totally, it was revealed that the tree species clearly affected macrofauna whereas nitrogen fixation did not.

Forest fire may disrupt plant–microbial feedbacks

“…While an observed effect of tree species on soil communities under field conditions may just reflect variation in the microhabitat occupied by the tree species, the fact that we sampled across eucalypt microhabitats within our site (i.e., mixed and pure stands), suggests that it was likely that eucalypt species modified soil microbial communities. Few studies have investigated whether eucalypt species modify distinct microbial communities (Anderson et al 2013;Orozco-Aceves et al 2015;Sayad et al 2012). Yet, these studies support our findings by showing that eucalypt species may differentially modify both soil chemical and biotic characteristics, potentially through species varying in traits (i.e., growth rate and chemistry) related to the quantity and quality of organic matter entering soils (Baxendale et al 2014;Orwin et al 2010).…”

“…The genus is of economic and ecological importance and, therefore, it is important to determine what factors drive the performance of these species. While there are some reports of eucalypt species differentially influencing soil chemical properties (Orozco-Aceves et al 2015;Sayad et al 2012), there is also evidence to suggest that eucalypt species can differentially modify soil communities. For instance, Anderson et al (2013) found that E. saligna and E. sideroxylon seedlings modified distinct soil fungal communities after just five month's growth in a greenhouse experiment.…”

Light, earthworms, and soil resources as predictors of diversity of 10 soil invertebrate groups across monocultures of 14 tree species

“…Plants are expected to influence the presence and abundance of invertebrate ecosystem engineers, partly through variation of litter quantity and quality among plant species (Lavelle et al, 1997;Schwarz et al, 2015). Common garden experiments confirm this link; Reich et al (2005) and Sayad et al (2012) showed that variability of earthworm biomass across plantations of different tree species was positively correlated with the amount of calcium in leaf litter.…”

“…However, a synthesis of available evidence suggests that competition does not have large impacts on many taxa of soil organisms, perhaps due to spatial or temporal niche differentiation (Wardle, 2002(Wardle, , 2006; but see Giller, 1996;Deca€ ens, 2010). Several observational and experimental studies report a positive effect of resource availability on soil animal diversity (van der Wal et al, 2009;Mulder et al, 2012;Sayad et al, 2012). As the diversity of resources increases, diversity of soil animals is expected to rise due to enhanced opportunities for niche differentiation with respect to habitat use and sources of energy and nutrients (Anderson, 1978;Wardle, 2006;Coleman, 2008).…”

Different predictors determining litter decomposition rate in functional groups of the tree plantations in a common garden

“…The three first species are non-nitrogen-fixing tree and the others are nitrogen-fixing trees. The experimental plot layout and more information about the plantations were illustrated by Sayad et al (2012).…”