Tree species, tree genotypes and tree genotypic diversity levels affect microbe-mediated soil ecosystem functions in a subtropical forest

Abstract

Tree species identity and tree genotypes contribute to the shaping of soil microbial communities. However, knowledge about how these two factors influence soil ecosystem functions is still lacking. Furthermore, in forest ecosystems tree genotypes co-occur and interact with each other, thus the effects of tree genotypic diversity on soil ecosystem functions merit attention. Here we investigated the effects of tree species, tree genotypes and genotypic diversity levels, alongside soil physicochemical properties, on the overall and specific soil enzyme activity patterns. Our results indicate that tree species identity, tree genotypes and genotypic diversity level have significant influences on overall and specific soil enzyme activity patterns. These three factors influence soil enzyme patterns partly through effects on soil physicochemical properties and substrate quality. Variance partitioning showed that tree species identity, genotypic diversity level, pH and water content all together explained ~30% variations in the overall patterns of soil enzymes. However, we also found that the responses of soil ecosystem functions to tree genotypes and genotypic diversity are complex, being dependent on tree species identity and controlled by multiple factors. Our study highlights the important of inter- and intra-specific variations in tree species in shaping soil ecosystem functions in a subtropical forest.

First Insights into the Microbiome of a Mangrove Tree Reveal Significant Differences in Taxonomic and Functional Composition among Plant and Soil Compartments

“…To explore potential ecological functions in the rhizosphere of each individual tree, we analyzed activities of three important enzymes for C, N, and P acquisition-β-glucosidase (EC 3.2.1.21), N-acetylglucosaminidase (EC 3.1.6.1), and acid phosphatase (EC 3.1.3.2), respectively-in the soil samples, using 4-methylumbelliferone (MUB) derivatives and previously described methodology [15]. To prepare soil slurries, 50 mL of 50 mM sodium acetate buffer (pH 5.5) were added to 0.5 g portions of soil (wet weight, equivalent to 0.098-0.183 g dry weight) and homogenized for 5 min in a bath sonicator.…”

“…Such microbes must be adapted to both high and low salinity. Potential soil microbial ecological functions were characterized by measuring activities of important soil enzymes for the acquisition of macronutrients such as carbon (C; β-glucosidase), nitrogen (N; N-acetylglucosaminidase), and phosphorus (P; acid phosphatase) [15].…”

Differential biodiversity responses between kingdoms (plants, fungi, bacteria and metazoa) along an Alpine succession gradient

“…Indeed, recent studies have investigated links between particular groups of organisms, and general relationships between diversity and processes have been found. However, studies either detail microbial diversity across general vegetation, land use or habitat classes (Chen et al, 2015;Flores-Rentería, Rincón, Valladares, & Yuste, 2016;Kaiser et al, 2016;Paula et al, 2014), correlate the general processes governed by microbes (such as soil respiration, microbial biomass or microbial enzyme activities) with detailed surveys of plant communities (Purahong et al, 2016;Strecker, González Macé, Scheu, & Eisenhauer, 2016) or infer microbial diversity indirectly from the physiological profiling of soil samples ("functional diversity"), rather than determining taxonomic diversity directly via genetic analysis (Araya, Bartelheimer, Valle, Crujeiras, & García-Baquero, 2017;Klimek, Chodak, Jaźwa, & Niklińska, 2016;Klimek et al, 2015;Markowicz, Woźniak, Borymski, Piotrowska-Seget, & Chmura, 2015;Mureva & Ward, 2017). The responses of microbial functional and taxonomic diversities to changes in plant productivity are not directly comparable (Zhang, Johnston, Barberán, Ren, & Lü, 2017) and likely reflect the operation of different processes.…”

Tree genotype and seasonal effects on soil properties and biogeochemical functioning in Mediterranean pine forests

“…In fact, Courty et al (2010) demonstrated that Populus genotypes with varying rates of mycorrhizal colonization produced different amounts of the enzymes involved in nutrient mobilization. Moreover, Purahong et al (2016) demonstrated that, together with soil pH and water content, one-third of the overall patterns of soil enzymes could be explained by tree species identity and genotypic diversity. Trees have a major effect on seasonal resource availability as a result of the litter fall in autumn and belowground carbon exudation and nutrient uptake during the growing season (Kaiser et al, 2010;Šnajdr et al, 2011); therefore, seasonality and tree phenology may influence the quality and quantity of organic inputs in soil (Šnajdr et al, 2011).…”