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Robinson, J. M.

Publications and source records attributed to Robinson, J. M..

14 recordsLinked to original sources

Invertebrate species produce taxon-specific acoustic profiles under controlled conditions

Soil degradation threatens food security, climate regulation, biodiversity and human wellbeing worldwide. Up to 75% of the worlds soils are already degraded, and in response, global restoration efforts are rapidly scaling up to meet international targets. Monitoring soil biodiversity recovery remains a major barrier to tracking restoration success, particularly for invertebrates that underpin key processes including nutrient cycling and soil aggregation. Traditional sampling methods are labour-intensive, destructive and poorly suited to long-term or landscape-scale monitoring. Soil ecoacoustics is rapidly emerging as a promising non-destructive soil biodiversity monitoring tool. However, its capacity for taxonomic resolution of invertebrate groups remains untested. Here, we present a proof-of-concept study that establishes the potential for a soil invertebrate acoustic classifier. We used a low-cost, sound-attenuated recording system and quantified 19 spectral and temporal audio features from six morphologically and behaviourally distinct invertebrate species under controlled conditions. Acoustic profiles differed among taxa and generally clustered into podous and apodous groups (i.e., organisms with legs versus those without). Variation was driven primarily by taxon identity rather than body mass, suggesting that acoustic signatures capture taxon-specific traits. This work provides a foundation for developing automated acoustic classifiers that could enable scalable, non-destructive soil biodiversity monitoring.

ecology↗

Sounds of the underground reflect soil biodiversity dynamics across a grassy woodland restoration chronosequence

Fifty-nine percent of the worlds species inhabit the soil. However, soils are degrading at unprecedented rates, necessitating efficient, cost-effective, and minimally intrusive biodiversity monitoring methods to aid in their restoration. Ecoacoustics is emerging as a promising tool for detecting and monitoring soil biodiversity, recently proving effective in a temperate forest restoration context. However, understanding the efficacy of soil ecoacoustics in other ecosystems and bioregions is essential. Here, we applied ecoacoustics tools and indices (Acoustic Complexity Index, Bioacoustic Index, Normalised Difference Soundscape Index) to measure soil biodiversity in an Australian grassy woodland restoration chronosequence. We collected 240 soil acoustic samples from two cleared plots (continuously cleared through active management), two woodland restoration plots (revegetated 14-15 years ago), and two remnant vegetation plots over 5 days at Mount Bold, South Australia. We used a below-ground sampling device and sound attenuation chamber to record soil invertebrate communities, which were also manually counted. We show that acoustic complexity and diversity were significantly higher in revegetated and remnant plots than in cleared plots, both in-situ and in sound attenuation chambers. Acoustic complexity and diversity were also strongly positively associated with soil invertebrate abundance and richness, and each chronosequence age class supported distinct invertebrate communities. Our results provide support that soil ecoacoustics can effectively measure soil biodiversity in woodland restoration contexts. This technology holds promise in addressing the global need for effective soil biodiversity monitoring methods and protecting our planets most diverse ecosystems.

ecology↗

Sonic restoration: Acoustic stimulation enhances soil fungal biomass and activity of plant growth-promoting fungi

Ecosystem restoration interventions often utilise visible elements to restore an ecosystem (e.g., replanting native plant communities and reintroducing lost species). However, using acoustic stimulation to restore ecosystems has received little attention. Our study aimed to (a) investigate the potential effects of acoustic stimulation on fungal biomass and organic matter decomposition, which are both crucial components of ecosystem functioning and (b) assess the effect of acoustic stimulation on the growth rate and sporulation of the plant growth-promoting fungus Trichoderma harzianum. We played 70 dB and 90 dB soundscape treatments (@ 8 kHz) to green and rooibos teabags in compost in experimental mesocosms for 8 hours per day for 14 days to test whether acoustic stimulation affected fungal biomass and organic matter decomposition (a control mesocosm received only ambient sound stimulation <30 dB). We played a monotone soundscape (80 dB @ 8 kHz) over five days to Trichoderma harzianum to assess whether this stimulation affected the growth rate and sporulation of this fungus (control samples received only ambient sound stimulation <30 dB). We show that the acoustic stimulation treatments resulted in increased fungal biomass, greater decomposition, and enhanced T. harzianum conidia (spore) activity compared to controls. These results indicate that acoustic stimulation influences soil fungal growth and potentially facilitates their functioning. A piezoelectric effect and/or fungal mechanoreceptor stimulation are possible mechanisms. Our study highlights the potential of acoustic stimulation to alter important functional soil components, which could, with further development, be harnessed to aid ecosystem restoration.

ecology↗

Urban greenspace aerobiomes are shaped by soil conditions and land cover type

Growing evidence suggests that exposure to microbial biodiversity is important for human immunoregulation and health. Urban greenspaces harbour airborne bacterial communities (aerobiomes) with the potential to transfer beneficial bacteria to humans. However, limited studies have examined the ecological influences of soil, vegetation, and rainfall on aerobiomes in urban greenspaces. Here, we utilised 16S rRNA amplicon sequence data to analyse the effects of land cover, soil abiotic characteristics, surrounding vegetation diversity, and rainfall on aerobiome diversity and composition from 33 urban greenspace sites in Adelaide, South Australia. We sampled air and soil from two urban greenspace land cover types: highly-managed sports fields (n = 11) and minimally-managed nature parks (n = 22). Sports field aerobiomes had a distinct aerobiome community composition and higher alpha diversity than nature parks. Aerobiome alpha diversity was shaped more by soil abiotic characteristics, particularly soil pH and iron levels, than woody plant species diversity. Rainfall prior to sampling also had strong effects on the aerobiome community composition and associated with decreased alpha diversity. These findings point toward soil iron and pH management as pathways to increase aerobiome bacterial diversity. Our study shows that, with additional research, there is potential for greenspace managers and urban planners to target specific soil abiotic characteristics in urban greenspaces to improve microbiome-mediated urban health.

ecology↗

Bioenergetic mapping of 'healthy microbiomes' via compound processing potential imprinted in gut and soil metagenomes

Despite mounting evidence of their importance in human health and ecosystem functioning, the definition and measurement of healthy microbiomes remain unclear. More advanced knowledge exists on health associations for compounds used or produced by microbes. Environmental microbiome exposures (especially via soils) also help shape, and may supplement, the functional capacity of human microbiomes. Given the synchronous interaction between microbes, their feedstocks, and micro-environments, with functional genes facilitating chemical transformations, there exists an intriguing opportunity to examine microbiomes in terms of their capacity to process compounds relevant to human health. Here we integrate functional genomics and biochemistry frameworks to derive new quantitative measures of the potential for human gut and environmental soil metagenomes to process major compound classes (e.g., lipids, carbohydrates) and selected biomolecules (e.g., vitamins, short-chain fatty acids) linked to human health. Metagenome functional potential profile data were translated into a universal compound mapping landscape based on bioenergetic van Krevelen mapping of function-level meta-compounds and corresponding functional relative abundances, reflecting imprinted genetic capacity of microbiomes to metabolize an array of different compounds. We show that measures of compound processing potential associated with human health and disease (examining atherosclerotic cardiovascular disease, colorectal cancer, type 2 diabetes and anxious-depressive behavior case studies), and displayed seemingly predictable shifts along gradients of ecological disturbance in plant-soil ecosystems (three case studies). Ecosystem quality explained 60-92% of variation in soil metagenome compound processing potential measures in a post-mining restoration case study dataset. With growing knowledge of the varying proficiency of environmental microbiota to process human health associated compounds, we might design environmental interventions or nature prescriptions to modulate our exposures, thereby advancing microbiota-oriented approaches to human health. Compound processing potential offers a simplified, integrative approach for applying metagenomics in ongoing efforts to understand and quantify the role and linkages of microbiota in environmental- and human-health.

bioinformatics↗

The sound of restored soil: Measuring soil biodiversity in a forest restoration chronosequence with ecoacoustics

Forest restoration requires monitoring to assess changes in above- and below-ground communities, which is challenging due to practical and resource limitations. With emerging sound recording technologies, ecological acoustic survey methods--also known as ecoacoustics--are increasingly available. These provide a rapid, effective, and non-intrusive means of monitoring biodiversity. Above-ground ecoacoustics is increasingly widespread, but soil ecoacoustics has yet to be utilised in restoration despite its demonstrable effectiveness at detecting meso- and macrofauna acoustic signals. This study applied ecoacoustic tools and indices (Acoustic Complexity Index, Normalised Difference Soundscape Index, and Bioacoustic Index) to measure above- and below-ground biodiversity in a forest restoration chronosequence. We hypothesised that higher acoustic complexity, diversity and high-frequency to low-frequency ratio would be detected in restored forest plots. We collected n = 198 below-ground samples and n = 180 ambient and controlled samples from three recently degraded (within 10 years) and three restored (30-51 years ago) deciduous forest plots across three monthly visits. We used passive acoustic monitoring to record above-ground biological sounds and a below-ground sampling device and sound-attenuation chamber to record soil communities. We found that restored plot acoustic complexity and diversity were higher in the sound-attenuation chamber soil but not in situ or above-ground samples. Moreover, we found that restored plots had a significantly greater high-frequency to low-frequency ratio for soil, but no such association for above-ground samples. Our results suggest that ecoacoustics has the potential to monitor below-ground biodiversity, adding to the restoration ecologists toolkit and supporting global ecosystem recovery. Implications for PracticeO_LIThis is the first known study to assess the sounds of soil biodiversity in a forest restoration context, paving the way for more comprehensive studies and practical applications to support global ecosystem recovery. C_LIO_LISoil ecoacoustics has the potential to support restoration ecology/biodiversity assessments, providing a minimally intrusive, cost-effective and rapid surveying tool. The methods are also relatively simple to learn and apply. C_LIO_LIEcoacoustics can contribute toward overcoming the profound challenge of quantifying the effectiveness (i.e., success) of forest restoration interventions in reinstating target species, functions and so-called services and reducing disturbance. C_LI

ecology↗

Biogeography of human-health associated butyrate-producing bacteria

AimButyrate-producing bacteria are found in many outdoor ecosystems and host organisms, including humans, and are vital to ecosystem functionality and human health. These bacteria ferment organic matter, producing the short-chain fatty acid butyrate. However, few (if any) studies have examined the macroecological influences on their large-scale biogeographical distribution. Here we aimed to characterise their global biogeography together with key explanatory climatic, geographic, and physicochemical variables. LocationGlobal, and the Australian continent Time period2005-2020 Major taxa studiedButyrate-producing bacteria MethodsWe developed new normalised butyrate production capacity (BPC) indices derived from global metagenomic (n=13,078) and Australia-wide soil 16S rRNA (n=1,331) data, using Geographic Information System (GIS) and modelling techniques to detail their ecological and biogeographical associations. ResultsThe highest BPC scores were found in anoxic and fermentative environments, including the human and non-human animal gut, and in some plant-soil systems. Within plant-soil systems, roots and rhizospheres had the highest BPC scores. Among soil samples, geographic and climatic variables had the strongest overall influence on BPC scores, with human influence also making key contributions. Higher BPC scores were in soils from seasonally productive sandy rangelands, temperate rural residential areas, and sites with moderate-to-high soil iron concentrations. Main conclusionsAbundances of butyrate-producing bacteria in outdoor soils follow complex ecological patterns influenced by geography, climate, soil chemistry, and hydrological fluctuations. Human population density and soil iron also play substantial roles, and their effects are dependent on a combination of ecological variables. These new biogeographical insights further our understanding of the global ecology patterns of butyrate-producing bacteria, with implications for emerging microbially-focussed ecological and human health policies.

ecology↗

Germaphobia! Does our Relationship with, and Knowledge of Biodiversity Affect our Attitudes Towards Microbes?

Germaphobia -- a pathological aversion to microorganisms -- could be contributing to an explosion in human immune-related disorders via mass sterilisation of surfaces and reduced exposure to biodiversity. Loss of biodiversity and our connectedness to nature, along with poor microbial literacy may be augmenting the negative consequences of germaphobia on ecosystem health. In this study, we created an online questionnaire to acquire data on attitudes towards, and knowledge of microbes. We collected data on nature connectedness and interactions with nature and explored the relationships between these variables. We found a significant association between attitudes towards microbes and both duration and frequency of visits to natural environments. A higher frequency of visits to nature per week, and a longer duration spent in nature per visit, significantly associated with positive attitudes towards microbes. We found no association between nature connectedness and attitudes towards microbes. We found a significant relationship between knowledge of lesser known microbial groups (e.g., identifying that fungi, algae, protozoa, and archaea are microbes) and positive attitudes towards microbes. However, we also found that people who correctly identified viruses as being microbes expressed less positive views of microbes overall -- this could potentially be attributed to a COVID-19 effect. Our results suggest that basic microbial literacy and nature engagement may be important in reducing/preventing germaphobia. The results also suggest that a virus-centric phenomenon (e.g., COVID-19) could increase broader germaphobia. As the rise of immune-related disorders and mental health conditions have been linked to germaphobia, reduced biodiversity, and non-targeted sterilisation, our findings point to a feasible strategy to potentially help ameliorate these negative consequences. A greater emphasis on microbial literacy and promoting time spent in nature could be useful in promoting resilience in human health and more positive/constructive attitudes towards the foundations of our ecosystems - the microorganisms.

scientific communication and education↗

Mixed-stock analysis in the age of genomics: Rapture genotyping enables evaluation of stock-specific exploitation in a freshwater fish population with weak genetic structure

Mixed-stock analyses using genetic markers have informed fisheries management in cases where strong genetic differentiation occurs among local spawning populations, yet many fisheries are supported by multiple spawning stocks that are weakly differentiated. Freshwater fisheries exemplify this problem, with many harvested populations supported by multiple stocks of young evolutionary age that are isolated across small spatial scales. As a result, attempts to conduct genetic mixed-stock analyses of inland fisheries have often been unsuccessful. Advances in genomic sequencing now offer the ability to discriminate among populations with weak population structure by providing the necessary resolution to conduct mixed-stock assignment among previously indistinguishable stocks. We demonstrate the use of genomic data to conduct a mixed-stock analysis of Lake Eries commercial and recreational walleye (Sander vitreus) fisheries and estimate the relative harvest of weakly differentiated stocks (pairwise FST < 0.01). We used RAD-capture (Rapture) to sequence and genotype individuals at 12,081 loci that had been previously determined to be capable of discriminating between western and eastern basin stocks with 95% reassignment accuracy, which was not possible in the past with microsatellite markers. Genetic assignment of 1,075 fish harvested from recreational and commercial fisheries in the eastern basin indicated that western basin stocks constituted the majority of individuals harvested during peak walleye fishing season (July - September). Composition of harvest changed seasonally, with eastern basin fish comprising much of the early season harvest (May - June). Clear spatial structure in harvest composition existed; more easterly sites contained more individuals of east basin origin than did westerly sites. Our study provides important stock contribution estimates for Lake Erie fishery management and demonstrates the power of genomic data to facilitate mixed-stock analysis in exploited fish populations with weak population structure or limited existing genetic resources.

genomics↗

Exposure to Airborne Bacteria Depends upon Vertical Stratification and Vegetation Complexity

Exposure to biodiverse aerobiomes may support human health, but it is unclear which ecological factors influence exposure. Few studies have investigated near-surface green space aerobiome dynamics, and no studies have investigated aerobiome vertical stratification in different green spaces. We used columnar sampling and next generation sequencing of the bacterial 16S rRNA gene, combined with geospatial and network analyses to investigate aerobiome spatio-compositional dynamics. We show a strong effect of habitat on bacterial diversity and network complexity. We observed aerobiome vertical stratification and network complexity that was contingent on habitat type. Tree density, closer proximity, and canopy coverage associated with greater aerobiome alpha diversity. Grassland aerobiomes exhibited greater proportions of putative pathogens compared to scrub, and also stratified vertically. We provide new insights into the urban ecosystem with potential importance for public health, whereby the possibility of differential aerobiome exposures appears to depend on habitat type and height in the airspace.

ecology↗

Vertical Stratification in Urban Green Space Aerobiomes

Exposure to a diverse environmental microbiome is thought to play an important role in ‘educating’ the immune system and facilitating competitive exclusion of pathogens to maintain human health. Vegetation and soil are known to be key sources of airborne microbiota––the aerobiome. Only a limited number of studies have attempted to characterise the dynamics of the aerobiome, and no studies to date have investigated these dynamics from a vertical perspective simulating human exposure. Studies of pollution and allergenic pollen show vertical stratification at various scales, and present an expectation that such vertical stratification may also be present in the aerobiome. Such stratification could have important implications for public health and for the design, engineering and management of urban green spaces. For example, do children receive the same exposure to airborne microbiota as taller adults, and what are the downstream implications for health? In this study, we combine an innovative columnar sampling method at soil level, 0.0, 0.5, 1.0, and 2.0 m together with high-throughput sequencing of the bacterial 16S rRNA gene to assess whether significant vertical stratification of the aerobiome occurred in a parkland habitat in Adelaide, South Australia. Our results provide evidence of vertical stratification in both alpha and beta (compositional) diversity of airborne bacterial communities, with diversity increasing roughly with height. We also found significant vertical stratification in known pathogenic and beneficial bacterial taxa, suggesting potentially different exposure attributes between adults and children. These results could have important implications for public health and urban planning, potentially informing ways to optimise the design and management of health-promoting urban green spaces.Competing Interest StatementThe authors have declared no competing interest.View Full Text

ecology↗

Flavor-specific enhancement of electronic cigarette liquid consumption and preference in mice

BackgroundThe use of electronic cigarettes has increased over the past decade. To determine how the abuse liability of electronic cigarette liquids (e-liquids) differs from nicotine alone, and to determine the impact of flavor, we compared nicotine-containing fruit- and tobacco-flavored e-liquids, and their nicotine-free versions, to nicotine alone in mouse models of oral consumption, reward and aversion. MethodsAdult male C57BL/6J mice voluntarily consumed oral nicotine, equivalent nicotine concentrations of fruit- and tobacco-flavored e-liquid, and equivalent dilutions of the nicotine-free versions in 2-bottle choice tests. Conditioned place preference and place aversion were assessed with peripherally administered e-liquids or nicotine. Serum nicotine and cotinine levels were measured after subcutaneous injections of e-liquid or nicotine. ResultsMice showed higher consumption and preference for the fruit-flavored e-liquid compared with nicotine alone. This increase was not due to the flavor itself as consumption of the nicotine-free fruit-flavored e-liquid was not elevated until the highest concentration tested. The increased consumption and preference were not observed with the tobacco-flavored e-liquid. The conditioned place preference, place aversion and nicotine pharmacokinetics of the fruit-flavored e-liquid were not significantly different from nicotine alone. ConclusionsOur data suggest that fruit, but not tobacco flavor, increased the oral consumption of e-liquid compared with nicotine alone. Moreover, this enhancement was not due to increased consumption of the flavor itself, altered rewarding or aversive properties after peripheral administration, or altered pharmacokinetics. This flavor-specific enhancement suggests that some flavors may lead to higher nicotine intake and increased use of e-liquids compared with nicotine alone. HighlightsO_LIFruit flavor, but not tobacco flavor, enhances e-liquid consumption and preference C_LIO_LIThe nicotine-free flavored e-liquid is not preferred over nicotine alone C_LIO_LIConditioning rewarding and aversive effects are equal between nicotine and e-liquid C_LI

pharmacology and toxicology↗

Selective enhancement of alcohol aversion by nicotinic acetylcholine receptor drugs

The prevalence of alcohol use disorders (AUDs) has steadily increased in the United States over the last 30 years. Alcohol acts on multiple receptor systems including the nicotinic acetylcholine receptors (nAChRs), which are known to mediate alcohol consumption and reward. We previously reported that the preclinical drug sazetidine-A, a nAChR agonist, reduces alcohol consumption without affecting nicotine consumption in C57BL/6J mice. Here, we found that sazetidine-A enhances the expression of alcohol aversion without affecting the expression or acquisition of conditioned alcohol reward in C57BL/6J mice. Microinjection of sazetidine-A into the ventral midbrain targeting the ventral tegmental area (VTA) reduced binge alcohol consumption, implicating the neurocircuitries in this region in mediating the effects of sazetidine-A. Furthermore, sazetidine-A-induced reduction in alcohol consumption was mediated by non-4 containing nAChRs, as sazetidine-A reduced binge alcohol consumption in both 4 knock-out and wild-type mice. Finally, we found that in mice pre-treated with sazetidine-A, alcohol induced Fos transcript within Th-expressing but not Gad2-expressing neurons in the VTA as measured by increased Fos transcript expression. In summary, we find that sazetidine-A acts on non-4 nAChRs to enhance the expression of alcohol aversion, which may underlie the reduction in alcohol consumption induced by sazetidine-A. Elucidating the identity of non-4 nAChRs in alcohol aversion mechanisms will provide a better understanding the complex role of nAChRs in alcohol addiction and potentially reveal novel drug targets to treat AUDs.

neuroscience↗

Unequal interactions between alcohol and nicotine co-consumption: Suppression and enhancement of concurrent drug intake

RationaleAlcohol and nicotine addiction are prevalent conditions that co-occur. Despite the prevalence of co-use, factors that influence the suppression and enhancement of concurrent alcohol and nicotine intake are largely unknown.\n\nObjectivesOur goals were to assess how nicotine abstinence and availability influenced concurrent alcohol consumption, and to determine the impact of quinine adulteration of alcohol on aversion resistant alcohol consumption and concurrent nicotine consumption.\n\nMethodsMale and female C57BL/6J mice voluntarily consumed unsweetened alcohol, nicotine and water in a chronic 3-bottle choice procedure. In Experiment 1, nicotine access was removed for 1 week and re-introduced the following week, while the alcohol and water bottles remained available at all times. In Experiment 2, quinine (100-1000 M) was added to the 20% alcohol bottle, while the nicotine and water bottles remained unaltered.\n\nResultsIn Experiment 1, we found that alcohol consumption and preference were unaffected by the presence or absence of nicotine access in both male and female mice. In Experiment 2a, we found that quinine temporarily suppressed alcohol intake and enhanced concurrent nicotine, but not water, preference in both male and female mice. In Experiment 2b, chronic quinine suppression of alcohol intake increased nicotine consumption and preference in female mice without affecting water preference, whereas it increased water and nicotine preference in male mice.\n\nConclusionsQuinine suppression of alcohol consumption enhanced the preference for concurrent nicotine preference in male and female mice, suggesting that mice compensate for the quinine adulteration of alcohol by increasing their nicotine preference.

pharmacology and toxicology↗