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Biology subjects

Breed, M.

Publications and source records attributed to Breed, M..

6 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↗

Short-term passive greenspace exposures have little effect on nasal microbiomes: a cross-over exposure study of a Maori cohort

Indigenous health interventions have emerged in New Zealand aimed at increasing human interactions with and exposure to macro and microbial diversity. Urban greenspaces provide opportunities for people to gain such exposures. However, the dynamics and pathways of microbial transfer from natural environments onto a person remain poorly understood. Here, we analysed bacterial 16S rRNA amplicons in air samples (n = 7) and pre- and post-exposure nasal samples (n = 238) from 35 participants who had 30-minute exposures in an outdoor park. The participants were organised into two groups: over eight days each group had two outdoor park exposures and two indoor office exposures, with a cross-over study design and washout days between exposure days. We investigated the effects of participant group, location (outdoor park vs. indoor office), and exposures (pre vs. post) on the nasal bacterial community composition and three key suspected health-associated bacterial indicators (alpha diversity, generic diversity of Gammaproteobacteria, and read abundances of butyrate-producing bacteria). The participants had distinct nasal bacterial communities, but these communities did not display notable shifts in composition following exposures. The community composition and key health bacterial indicators were stable throughout the trial period, with no clear or consistent effects of group, location, or exposure. We conclude that 30-minute exposure periods to urban greenspaces are unlikely to create notable changes in the nasal microbiome of visitors, which contrasts with previous research. Our results suggest that longer exposures or activities that involves closer interaction with microbial rich ecological components (e.g., soil) are required for greenspace exposures to result in noteworthy changes in the nasal microbiome.

ecology↗

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↗

An intranasally administrated SARS-CoV-2 beta variant subunit booster vaccine prevents beta variant viral replication in rhesus macaques

Emerging of SARS-CoV-2 variants and waning of vaccine/infection-induced immunity poses threats to curbing the COVID-19 pandemic. An effective, safe, and convenient booster vaccine will be needed. We hypothesized that a variant-modified mucosal booster vaccine might induce local immunity to prevent SARS-CoV-2 infection at the port of entry. The beta-variant is hardest to cross-neutralize. Herein we assessed the protective efficacy of an intranasal booster composed of beta variant-spike protein S1 with IL-15 and TLR agonists in previously immunized macaques. The macaques were first vaccinated with Wuhan strain S1 with the same adjuvant. One year later, negligibly detectable SARS-CoV-2-specific antibody remained. Nevertheless, the booster induced vigorous humoral immunity including serum- and bronchoalveolar lavage (BAL)-IgG, secretory nasal- and BAL-IgA, and neutralizing antibody against the original strain and/or beta variant. Beta-variant S1-specifc CD4+ and CD8+ T cell responses were also elicited in PBMC and BAL. Following SARS-CoV-2 beta variant challenge, the vaccinated group demonstrated significant protection against viral replication in the upper and lower respiratory tracts, with almost full protection in the nasal cavity. The fact that one intranasal beta-variant booster administrated one year after the first vaccination provoked protective immunity against beta variant infections may inform future SARS-CoV-2 booster design and administration timing.

immunology↗

Next generation restoration metrics: Using soil eDNA bacterial community data to measure trajectories towards rehabilitation targets

In post-mining rehabilitation, successful mine closure planning requires specific, measurable, achievable, relevant and time-bound (SMART) completion criteria, such as returning ecological communities to match a target level of similarity to reference sites. Soil microbiota are fundamentally linked to the restoration of degraded ecosystems, helping to underpin ecological functions and plant communities. High-throughput sequencing of soil eDNA to characterise these communities offers promise to help monitor and predict ecological progress towards reference states. Here we demonstrate a novel methodology for monitoring and evaluating ecological restoration using three long-term (> 25 year) case study post-mining rehabilitation soil eDNA-based bacterial community datasets. Specifically, we developed rehabilitation trajectory assessments based on similarity to reference data from restoration chronosequence datasets. Recognising that many alternative options for microbiota data processing have potential to influence these assessments, we comprehensively examined the influence of standard versus compositional data analyses, different ecological distance measures, sequence grouping approaches, eliminating rare taxa, and the potential for excessive spatial autocorrelation to impact on results. Our approach reduces the complexity of information that often overwhelms ecologically-relevant patterns in microbiota studies, and enables prediction of recovery time, with explicit inclusion of uncertainty in assessments. We offer a step change in the development of quantitative microbiota-based SMART metrics for measuring rehabilitation success. Our approach may also have wider applications where restorative processes facilitate the shift of microbiota towards reference states.

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↗