Damien Finn

Thünen Institute | vTI · Institute of Biodiversity

The analysis of 18S rRNA gene amplicons is an important tool to characterize the diversity of the eukaryotic soil microbiome. Here we analyzed two primer sets (TAReuk, EKeuk) and the impact of a newly designed antifungal peptide nucleic acid to enhance the detection of protists in silico and with soil DNA extracted from croplands and a forest. The...

Soil aggregation is critical for high-clay Vertisols to facilitate water movement, aeration, nutrient cycling, microbial activity, and hence soil productivity. Both abiotic and biotic factors affect aggregation, although the effect of biotic factors on aggregation remains unclear in subtropical Vertisols managed under no-till (NT), stubble retained...

Alpha-diversity indices are an essential tool for describing and comparing biodiversity. Microbial ecologists apply indices originally intended for, or adopted by, macroecology to address questions relating to taxonomy (conserved marker) and function (metagenome-based data). In this Perspective piece, I begin by discussing the nature and mathematic...

A multi-stage option to address food-safety can be produced by a clearer understanding of Campylobacter's persistence through the broiler production chain, its environmental niche and its interaction with bacteriophages. This study addressed Campylobacter levels, species, genotype, bacteriophage composition/ levels in caeca, litter, soil and carcas...

The abundances of fungi and bacteria in soil are used as simple predictors for carbon dynamics, and represent widely available microbial traits. Soil biomarkers serve as quantitative estimates of these microbial groups, though not quantifying microbial biomass per se. The accurate conversion to microbial carbon pools, and an understanding of its co...

Soil organic carbon (SOC) dynamics are vital in the context of climate change and sustainable soil management. The ẟ13C signatures of SOC are powerful indicators and tracers of C fluxes through soils and of transformation processes within soils. Depth gradients of ẟ13C can be considered as their archive. However, many different drivers and processe...

Ammonia (NH3) inhibition represents a major limitation to methane production during anaerobic digestion of organic material in biogas reactors. This process relies on co-operative metabolic interactions between diverse taxa at the community-scale. Despite this, most investigations have focused singularly on how methanogenic Archaea respond to NH3 s...

The Pastaza-Marañón Foreland Basin (PMFB) holds the most extensive tropical peatland area in South America. PMFB peatlands store ~7.07 Gt of organic carbon interacting with multiple microbial heterotrophic, methanogenic, and other aerobic/anaerobic respirations. Little is understood about the contribution of distinct microbial community members inh...

The Pastaza-Maranon Foreland Basin (PMFB) holds the most extensive tropical peatland area in South America. PMFB peatlands store 7.07 Gt of organic carbon interacting with multiple microbial heterotrophic, methanogenic, and other oxic/anoxic respirations. Little is understood about the contribution of distinct microbial community members inhabiting...

The Black Queen hypothesis describes the evolutionary strategy to lose costly functions in favour of improving growth efficiency. This results in mutants (cheaters) becoming obligately dependent upon a provider (black queen) to produce a necessary resource. Previous analyses demonstrate black queens and cheaters reach a state of equilibrium in pair...

Water is necessary for all life on Earth. Water is so critical that organisms have developed strategies to survive in hyperarid environments. These regions with extremely low water availability are also unique analogs in which to study the physico-chemical conditions of extraterrestrial environments such as Mars. We have identified a daily, sustain...

Despite adoption of high-throughput sequencing of PCR-amplified microbial taxonomic markers for ecological analyses, distinct approaches for preparing amplicon libraries exist. One approach utilises long fusion primers and a single PCR (one-step) while another utilises shorter primers in a first reaction, before transferring diluted amplicons to a...

Microbiome analysis is becoming common in select municipal and service ecosystems, including wastewater treatment and anaerobic digestion, but its potential as a microbial-status-informative tool to promote or mitigate CH 4 production has not yet been evaluated in landfills. Methanogenesis mediated by Archaea is highly active in solid-waste microbi...

Air carries a diverse load of particulate microscopic biological matter in suspension, either aerosolized or aggregated with dust particles, the aerobiome, which is dispersed by winds from sources to sinks. The aerobiome is known to contain microbes, including pathogens, as well as debris or small-sized propagules from plants and animals, but its v...

Crop harvest followed by a fallow period can act as a disturbance on soil microbial communities. Cropping systems intended to improve alpha-diversity of communities may also confer increased compositional stability during succeeding growing seasons. Over a single growing season in a long-term (18 year) agricultural field experiment incorporating co...

While land conversion from native vegetation to agriculture influences the concentration, speciation, and cycling of soil phosphorus (P), the nature of these changes remain poorly understood. We collected surface soils (0–10 cm) from paired sites at three locations, comparing soil from native vegetation with adjacent soils converted for cropping, p...

Tropical peatlands are hotspots of methane (CH4) production but present high variation and emission uncertainties in the Amazon region. This is because the controlling factors of methane production in tropical peats are not yet well documented. Although inhibitory effects of nitrogen oxides (NOx) on methanogenic activity are known from pure culture...

Functional, physiological traits are the underlying drivers of niche differentiation. A common framework related to niches occupied by terrestrial prokaryotes is based on copiotrophy or oligotrophy, where resource investment is primarily in either rapid growth or stress tolerance, respectively. A quantitative trait-based approach sought relationshi...

Niche is a fundamental concept in ecology. It integrates the sum of biotic and abiotic environmental requirements that determines a taxon's distribution. Microbiologists currently lack quantitative approaches to address niche-related hypotheses. We tested four approaches for the quantification of niche breadth and overlap of taxa in amplicon sequen...

Tropical peatlands are globally important carbon reservoirs that play a crucial role in fluxes of atmospheric greenhouse gases. Amazon peatlands are expected to be large source of atmospheric methane (CH4) emissions, however little is understood about the rates of CH4 flux or the microorganisms that mediate it in these environments. Here we studied...

Soil aggregates are the ‘building blocks’ of soil structure. Aggregation dominantly influences the physico-chemical and biological properties of soil. Farm management practices can alter soil aggregation, which can potentially influence carbon dioxide (CO2) fluxes. We examined the effect of soil aggregate size on CO2 fluxes in a Vertisol following...

Nitrogen mining is the process whereby microbial communities catabolise recalcitrant long-term organic matter (OM) to meet nutritional requirements that are not ensured by labile OM. Microbial degradation of recalcitrant OM impacts soil fertility and contributes to greenhouse gas emissions in agricultural systems. Here we conducted a transcriptomic...

Understanding the cycling of C and N in soils is important for maintaining soil fertility while also decreasing greenhouse gas emissions, but much remains unknown about how organic matter (OM) is stabilized in soils. We used nano-scale secondary ion mass spectrometry (NanoSIMS) to investigate changes in C and N in a Vertisol and an Alfisol incubate...

Quantifying changes in stocks of C, N, P, and S in agricultural soils is important not only for managing these soils sustainably as required to feed a growing human population, but for C and N, they are also important for understanding fluxes of greenhouse gases from the soil environment. In a global meta-analysis, 102 studies were examined in orde...

Labile soil dissolved organic carbon (DOC) and heat-extracted carbon (HEC) are sensitive indicators of changing soil organic carbon (SOC) stocks. Isotope ratio mass spectrometry (IRMS) is an important tool for studying SOC turnover and soil biological function. Several complications are involved in measuring DOC/HEC, for example salt ionic strength...

Carbon (C) sequestration in soils is a means for increasing soil organic carbon (SOC) stocks and is a potential tool for climate change mitigation. One recommended management practice to increase SOC stocks is nitrogen (N) fertilisation, however examples of positive, negative or null SOC effects in response to N addition exist. We evaluated the rel...

Increasing organic carbon inputs to agricultural soils through the use of pastures or crop residues has been suggested as a means of restoring soil organic carbon lost via anthropogenic activities, such as land use change. However, the decomposition and retention of different plant residues in soil, and how these processes are affected by soil prop...

Methane is a potent greenhouse gas with a global warming potential similar to 28 times that of carbon dioxide. Consequently, sources and sinks that influence the concentration of methane in the atmosphere are of great interest. In Australia, agriculture is the primary source of anthropogenic methane emissions (60.4% of national emissions, or 3 260...