Community Response Research Articles

Contributions of the bacterial communities to the microcystin degradation and nutrient transformations during aerobic composting of algal sludge

Aerobic composting is a useful method for managing and disposing of salvaged algal sludge. To optimize the composting process and improve compost quality, it is necessary to understand the functions and responses of microbial communities therein. This work studied the degradation process of organic matter and the assemblage of bacterial communities in algal sludge composting via 16S rRNA amplicon sequencing. The results showed that 77.08% of the microcystin was degraded during the thermophilic stage of composting, which was the main period for microcystin degradation. Bacterial community composition and diversity changed significantly during the composting, and gradually stabilized as the compost matured. Different composting stages may be dominated by different module groups separately, as shown in the co-occurrence networks of composting bacterial communities. In the networks, all bacteria associated with microcystin degradation were identified as connectors between different module groups. The algal sludge composting process was driven primarily by deterministic processes, and the main driving forces for bacterial community assembly were temperature, dissolved organic carbon, ammonium, and microcystin. At last, by applying the structural equation modeling method, the bacterial communities under influences of physiochemical properties were proved as the main mediators for the microcystin degradation. This study provides valuable insights into the optimization of bacterial communities in composting to improve the efficiency of microcystin degradation and the quality of the compost product.

Impact of elevated CO2 on microbial communities and functions in riparian sediments: Role of pollution levels in modulating effects

The impact of elevated CO2 levels on microorganisms is a focal point in studying the environmental effects of global climate change. A growing number of studies have demonstrated the importance of the direct effects of elevated CO2 on microorganisms, which are confounded by indirect effects that are not easily identified. Riparian zones have become key factor in identifying the environmental effects of global climate change because of their special location. However, the direct effects of elevated CO2 levels on microbial activity and function in riparian zone sediments remain unclear. In this study, three riparian sediments with different pollution risk levels of heavy metals and nutrients were selected to explore the direct response of microbial communities and functions to elevated CO2 excluding plants. The results showed that the short-term effects of elevated CO2 did not change the diversity of the bacterial and fungal communities, but altered the composition of their communities. Additionally, differences were observed in the responses of microbial functions to elevated CO2 levels among the three regions. Elevated CO2 promoted the activities of nitrification and denitrification enzymes and led to significant increases in N2O release in the three sediments, with the greatest increase of 76.09 % observed in the Yuyangshan Bay (YYS). Microbial carbon metabolism was promoted by elevated CO2 in YYS but was significantly inhibited by elevated CO2 in Gonghu Bay and Meiliang Bay. Moreover, TOC, TN, and Pb contents were identified as key factors contributing to the different microbial responses to elevated CO2 in sediments with different heavy metal and nutrient pollution. In conclusion, this study provides in-depth insights into the responses of bacteria and fungi in polluted riparian sediments to elevated CO2, which helps elucidate the complex interactions between microbial activity and environmental stressors.

Professionals' Readiness to Manage Violence Against Women.

Over recent years, community-based responses to domestic violence against women have become an important topic, and there is growing recognition that domestic violence requires a comprehensive response from agencies across a variety of community sectors. When reaching out for help, female survivors of domestic violence need to have access to a broad range of services, empowering professionals to manage violence against women, and coordinated community responses that promotes safety, autonomy, and integration. Since the early 1990s, Portugal has been gradually moving toward a community-based approach to domestic violence against women where local organizations and professionals are major stakeholders of this policy. Besides having had an increased network of services implemented, it is important to examine how prepared service providers are to respond effectively. The current study analyzed how ready professionals in Portugal are to deliver interventions targeting violence against women. A total of 585 professionals from different backgrounds completed a readiness survey. The results revealed that, despite their perceived readiness, professionals are not duly prepared to respond effectively to violence against women. They lack the appropriate knowledge and training to respond effectively to survivors. Hence, further efforts must be made to change professional practices and services to ensure that abuse is recognized, barriers are overcome, and interventions are more effective.

Differential insights into the distribution characteristics of archaeal communities and their response to typical pollutants in the sediments and soils of deep-water reservoir

This study focused on the Fengshuba deep-water reservoir in South China, and systematically explored the distribution characteristics of archaeal communities in the sediment and soil in water level fluctuation zones and their response mechanisms to typical pollutants. The results show that Euryarchaeota and Bathyarchaeota are the dominant phyla in sediment archaeal communities, while Thaumarchaeota dominates in soil. The absolute abundance of archaea in the sediments was lower than that in the soils, but the diversity and richness of archaeal communities were higher than those in the soils. Seasonal changes affected the composition of sediment archaeal communities, and the archaeal compositions in the two habitats also showed significant differences. The neutral community model indicates that the assembly of archaeal communities in sediments is mainly governed by stochastic processes, while deterministic processes dominate in soils. The responses of archaeal communities to pollutants in the two habitats were significantly different. Among them, the carbon-nitrogen ratio and tetracycline concentration are the key factors driving seasonal changes in the archaeal communities in the sediment. Structural equation modeling further showed that the archaeal community in the sediment was positively correlated with organochlorine pesticides and antibiotics, while the archaeal community in the soil showed an opposite trend. This study provides new insights into the complexity of interactions between archaeal communities and typical contaminants in reservoir systems.

Rapid Responses of Greenhouse Gas Emissions and Microbial Communities to Carbon and Nitrogen Addition in Sediments.

Massive labile carbon and nitrogen inputs into lakes change greenhouse gas emissions. However, the rapid driving mechanism from eutrophic and swampy lakes is not fully understood and is usually contradictory. Thus, we launched a short-term and anaerobic incubation experiment to explore the response of greenhouse gas emissions and microbial communities to glucose and nitrate nitrogen (NO3--N) inputs. Glucose addition significantly increased CH4 and CO2 emissions and decreased N2O emissions, but there were no significant differences. NO3--N addition significantly promoted N2O emissions but reduced CH4 accumulative amounts, similar to the results of the Tax4Fun prediction. Bacterial relative abundance changed after glucose addition and coupled with the abundance of denitrification genes (nirS and nirK) decreased while maintaining a negative impact on N2O emissions, considerably increasing methanogenic bacteria (mcrA1) while maintaining a positive impact on CH4 emissions. Structural equation modeling showed that glucose and NO3--N addition directly affected MBC content and greenhouse gas emissions. Further, MBC content was significantly negative with nirS and nirK, and positive with mcrA1. These results significantly deepen the current understanding of the relationships between labial carbon, nitrogen, and greenhouse emissions, further highlighting that labile carbon input is the primary factor driving greenhouse gas emissions from eutrophic shallow lakes.

Macrobenthos community responses to tidal barrier in a sub-tropical river estuary: Insights for coastal management

Understanding the impacts of tidal barriers on macrobenthos is essential for comprehending anthropogenic influences on coastal ecosystems and biodiversity. This study aimed to address two primary questions: firstly, whether there are differences in macrobenthos abundance and diversity between the protected (CPA) and non-protected areas (CNPA) characterized by the tidal barrier, and secondly, whether the environmental factors associated with tidal barriers influence the macrobenthos community structure. Samples collected from CPA and CNPA sites from a subtropical river-estuary revealed the presence of 16 taxa of soft-bottom invertebrates, with a predominant presence of Ampeliscidae, Capitellidae, Glyceridae, Oligochaeta, Mysidae, Mytilidae, Naticidae, Portunidae, and Insecta. Significant differences (p < 0.05) in salinity and conductivity were observed between CPA and CNPA. In the CPA area, the average temperature was 23.21°C, dissolved oxygen was 4.81 mg/L, and pH was 7.91, all of which were higher compared to CNPA.Macrobenthos abundance was higher in CNPA (1506 ± 688 ind.m−2) compared to CPA (1330 ± 611 ind.m−2) (p < 0.05) with distinct dominance patterns of Polychaeta and Malacostraca. CNPA showed lower species dominance index (0.10–0.24), higher species diversity index (1.52–2.38), slightly higher Margalef`s index (from 0.63 to 1.6), and lower Shannon Index (from 0.69 to 0.85) indicating a more balanced community structure with a more diverse assemblage of species than CPA and a moderately polluted area. Hierarchical cluster analysis (HCA), Non-metric multidimensional scaling (nMDS) analysis, and Canonical Correspondence Analysis (CCA) indicated that the tidal barrier negatively impacted the macrobenthic families. The findings indicated the influencing effect of the breakwater defensive system on the macrobenthos assemblage at the estuary and informed policymakers and environmental scientists to develop environment-friendly breakwater defense systems.

Response of parasitoid communities to insecticide application during a Lymantria dispar outbreak in mixed oak forests

Abstract In the temperate mixed oak forests of Central Europe, outbreaks of insects such as the spongy moth, Lymantria dispar, can cause severe defoliation and insecticide is sometimes applied for their control. Parasitoids, mainly Hymenoptera and Diptera, are among the most diverse and important natural enemies of caterpillars in these forests. However, due to their cryptic lifestyle and taxonomic difficulties, we lack knowledge on the impact of insecticide applications on complex host‐parasitoid networks. In a large‐scale field experiment, we tested the effect of spraying the lepidopteran‐specific insecticide Mimic (tebufenozide) on the abundance and community composition of both adult and larval parasitoids. We combined morphological identification, DNA barcoding and metabarcoding to identify parasitoids adult or inside caterpillars, both sampled by canopy fogging during an outbreak and two subsequent years. We analysed the abundance of parasitoids, community composition and network specialisation using statistical methods that account for sample incompleteness in host‐parasitoid data. For adult parasitoid assemblages, we found strong annual effects on abundance, with highest numbers of adult parasitoids occurring in the outbreak year, as well as on annual changes in community composition, but no effect linked to insecticide application. However, the abundance and species number of immature parasitoids revealed negative effects of insecticide application, while community composition was only affected by annual variation. Coverage‐based network analyses showed a reduction of taxonomic network diversity and network specialisation associated with insecticide application in the first 2 years. Synthesis and applications: This real‐world experiment shows that parasitoid populations respond immediately to large‐scale outbreaks but only limited to local disturbances. Results indicate that this group of natural enemies exhibits high mobility, enabling them to track host populations across large spatial scales. However, our observation of reduced network specialisation after insecticide application is a warning signal that ecosystem function, and consequently natural pest control services, may be impaired by human interference at the local stand scale.

Response of sedimentary microbial community and antibiotic resistance genes to aged Micro(Nano)plastics exposure under high hydrostatic pressure

Several studies reported that the presence of microplastics (MPs)/nanoplastics (NPs) in marine environments can alter microbial community and function. Yet, the impact of aged MPs/NPs on deep sea sedimentary ecosystems under high hydrostatic pressure remains insufficiently explored. Herein, the sedimentary microbial community composition, co-occurrence network, assembly, and transfer of antibiotic resistance genes (ARGs) in response to aged MPs/NPs were investigated. Compared with the control, NPs addition significantly reduced bacterial alpha diversity (p < 0.05), whereas MPs showed no significant impact (p > 0.05). Moreover, networks under NPs exhibited decreased complexity than that under MPs and the control, including edges, average degree, and the number of keystone. The assembly of the microbial community was primarily governed by stochastic processes, and aged MPs/NPs increased the importance of stochastic processes. Moreover, exposure to MPs/NPs for one month decreased the abundance of antibiotic resistance genes (ARGs) (from 94.8 to 36.2 TPM), while exposure for four months increased the abundance (from 40.6 to 88.1 TPM), and the shift of ARGs in sediment was driven by both functional modules and microbial community. This study is crucial for understanding the stress imposed by aged MPs/NPs on sedimentary ecosystems under high hydrostatic pressure.

Microbial community response to temperature reduction during anaerobic treatment of long chain fatty acids-containing wastewater

Acclimating mesophilic biomass to low temperatures have been used to start-up psychrophilic anaerobic reactors, but limited microbial information is available during the acclimation. To investigate microbial responses to temperature reductions, duplicate lab-scale anaerobic digestion (AD) reactors were operated for 166 days, with the temperature being reduced from 37°C to 15°C, using synthetic long chain fatty acid (LCFA)-containing wastewater as the feedstock. The acclimated biomass at 15°C exhibited efficient removal of organic matter (total COD>75%, soluble COD>88%, and LCFA>99%). Temperature reductions lead to significant reductions in microbiome diversity. Fermentative bacteria were highly dynamic and functional redundant during temperature reductions. Smithella was the dominant syntrophic bacteria involved in LCFA degradation coupled with Methanothrix and Methanocorpusculum at 15°C. Membrane modifications and compatible cellular solutes production were triggered by temperature reductions as microbial response to cold stress. This study provided molecular insights in microbial acclimation to low temperatures for psychrophilic AD.

Benthic taxonomic and functional diversity change across a depth gradient in the Southern Benguela Shelf ecoregion

Functional trait-based approaches improve biodiversity assessment and have consequently been gaining traction in ecology, including marine benthic studies. However, taxonomic diversity is still the default biodiversity metric applied to monitor benthic community responses to environmental variation despite not always representing functional diversity change. Therefore, we used Biological Traits Analysis (BTA) to quantify functional diversity for infauna and epifauna communities collected from the same locations across a depth gradient in the Southern Benguela Shelf ecoregion. Infauna experienced an increase in functional uniqueness with depth, whereas epifauna experienced an increase in functional redundancy with depth. As a result, the epifauna species assemblage predicted 43 % of the epifauna trait assemblage, whereas the infauna species assemblage predicted only 8 % of the infauna trait assemblage. These findings suggest that taxonomic diversity and functional diversity changes are not congruent within and between marine benthic faunal groups. We emphasize the need to utilise both biodiversity metrics when quantifying marine biodiversity for conservation and management objectives.

‘Mostly women's issues’ – Gender differences in community responses to a large-scale NGO programme to prevent violence against women in urban India

Despite striking gender differences in men's and women's engagement in past prevention programmes to stop violence against women (VAW), few empirical studies have determined why such gender differences arise. We did a grounded theory study of a large-scale NGO programme in informal settlements in Mumbai, India, aiming to analyse how gender affects participation in community action to address VAW. We did 27 focus group discussions and 31 semi-structured interviews with 77 women and 36 men, as well as with 9 NGO staff. We supplemented qualitative data with quantitative monitoring data on referrals to NGO counselling centres. We found that male participants in the NGO programme not only reported violence to the NGO at lower rates but took less intensive action to support survivors. When they did engage, they more often defended perpetrators or asked survivors to accommodate them than female participants. These differences could be explained by a greater (1) affective response to VAW (2) perceived stake in addressing VAW (3) sense of empowerment from taking action, and (4) perceived NGO support for self among women compared to men. Differences were evident even between male and female participants who had taken part in NGO activities for years. We theorise that these differences ultimately stem from men and women's structurally different position in a gender unequal society. Our findings identify key motivational barriers to address to improve the effectiveness of programmes to prevent VAW. Given the greater barriers to men's community action compared to women's community action, it may be useful to recognize the value of prevention programmes with differing levels of male engagement, including women-only programmes and programmes in which male community participants play a secondary role and are not expected to be as active as female participants.

Macroseismic Analysis of the 2023 Earthquakes in Jayapura

On January 2 and February 9, 2023, two significant earthquakes struck Jayapura City, leading to widespread panic, severe damage to buildings and public infrastructure, and multiple casualties. In response, the BBMKG V Earthquake Survey Team conducted a macroseismic study to evaluate the geological impacts, assess community responses, and document the overall effects of the earthquakes. The methodology employed included structured interviews and questionnaires administered to affected residents. The study revealed that soft rock conditions in the area contributed to an MMI scale VI impact, which resulted in extensive damage to public facilities and residential buildings. The insights gained from this study offer valuable information for improving future earthquake mitigation strategies and enhancing preparedness in seismically vulnerable regions.

Habitat type controls microarthropod community changes across a Magellanic sub-Antarctic elevation gradient

IntroductionElevation gradients are often used as a proxy for climate change as they allow comparisons of ecological responses over much larger temporal and spatial scales than is possible through experimental manipulations.MethodsHere, we tested how microarthropod communities (Collembola and Acari) are affected by climatic differences between sea level and 600 m a.s.l. on Navarino Island, in the Magellanic sub-Antarctic ecoregion of southern Chile (mean annual temperatures of 5.6 vs 3.1°C, respectively). We quantified microarthropod abundance, richness and community trait characteristics in dominant moss (Racomitrium lanuginosum and Polytrichum strictum) and lichen (Usnea trachycarpa, Pseudocyphellaria freycinetii and Stereocaulon alpinum) vegetation growing at both elevations. These moss and lichen genera are characterized by large morphological differences and allow testing of how habitat characteristics affect microarthropod community response across elevation gradients.ResultsCollembola and Acari community composition differed between the low and high elevation sites. Total abundance levels of Acari were maintained in each habitat across elevation, whereas Collembola richness strongly declined (50%) at high elevation in the moss habitats. Acari community differences across elevation were driven by relative abundance changes whereas the Collembola community lost species at higher elevation. An anticipated decline of smaller eudaphic Collembola at high elevation was only observed in the moss Racomitrium, reflecting potentially lower temperature buffering capacity and shelter options compared to Polytrichum. Lichens mostly supported larger epigeic species irrespective of elevation. There were no consistent patterns linking microarthropod communities with habitat water holding capacity or water loss rates across the studied habitats and elevation.DiscussionHabitat type and the genus of moss or lichen were associated with microarthropod community changes across elevation, including examples of declines, increases and no change. These findings highlight that community responses across gradients may not always relate to the generally hypothesized environmental variables (e.g. temperature variability) and that habitat characteristics should be taken into account when using elevation as a proxy for climate change.

Impact of naphthalene on soil fauna diversity: Consequences for ecosystem functioning and carbon cycling in grasslands

Soil fauna, key indicators of grassland ecosystem health, face significant threats from the vast amounts of chemical pollutants released by human activities. These organisms are crucial for fundamental processes such as litter decomposition and carbon cycling. However, the response of soil animal communities and their functional dynamics to environmental chemical stress remains poorly understood. To investigate this, we conducted a naphthalene addition and litterbag experiment in the Bashang Grassland, located on the southern Inner Mongolia Plateau, to analyze its effects on soil fauna and litter decomposition. The investigated soil fauna groups included Arachnida (Arachnids), Insecta (Insects), Collembola (Springtails), Enoplea (enopleans), and Chromadorea (chromadoreans). The litter composition included Leymus chinensis, Stipa krylovii, Artemisia, Saussurea amara, and Artemisia giraldii. The findings indicated that a high diversity of soil fauna enhanced the decomposition of litter and the release of organic carbon from the litter. While the addition of naphthalene decreased both the abundance of soil fauna and the rate of litter decomposition, it specifically increased the relative proportion of Collembola (Springtails). Microfauna and mesofauna (0.1–2.0 mm) contributed more to the loss of litter mass and the release of organic carbon from the litter than macrofauna (2.0–4.0 mm). The effects of diverse soil fauna on litter decomposition and soil organic carbon accumulation were diminished by naphthalene exposure. This study further reveals the relationship between composite soil fauna diversity, litter decomposition, and soil organic carbon under chemical stress, highlighting the threat of environmental pollution to ecosystem health. It also enriches our understanding of the complexity of grassland ecosystems, especially in response mechanisms under chemical pollution stress.

The impact of trait number and correlation on functional diversity metrics in real-world ecosystems.

The use of trait-based approaches to understand ecological communities has increased in the past two decades because of their promise to preserve more information about community structure than taxonomic methods and their potential to connect community responses to subsequent effects of ecosystem functioning. Though trait-based approaches are a powerful tool for describing ecological communities, many important properties of commonly-used trait metrics remain unexamined. Previous work with simulated communities and trait distributions shows sensitivity of functional diversity measures to the number and correlation of traits used to calculate them, but these relationships have yet to be studied in actual plant communities with a realistic distribution of trait values, ecologically meaningful covariation of traits, and a realistic number of traits available for analysis. To address this gap, we used data from six grassland plant communities in Minnesota and New Mexico, USA to test how the number of traits and the correlation between traits used in the calculation of eight functional diversity indices impact the magnitude of functional diversity metrics in real plant communities. We found that most metrics were sensitive to the number of traits used to calculate them, but functional dispersion (FDis), kernel density estimation dispersion (KDE dispersion), and Rao's quadratic entropy (Rao's Q) maintained consistent rankings of communities across the range of trait numbers. Despite sensitivity of metrics to trait correlation, there was no consistent pattern between communities as to how metrics were affected by the correlation of traits used to calculate them. We recommend that future use of evenness metrics include sensitivity analyses to ensure results are robust to the number of traits used to calculate them. In addition, we recommend use of FDis, KDE dispersion, and Rao's Q when ecologically applicable due to their ability to produce consistent rankings among communities across a range of the numbers of traits used to calculate them.

New insights into the inhibition performance and mechanisms of sodium dodecyl benzene sulfonate (SDBS) on nitrogen removal in activated sludge-biofilm system

To investigate the effect of sodium dodecyl benzene sulfonate (SDBS) on nitrogen (N) removal performance and biological mechanisms, a gradient of SDBS concentrations was introduced into a set of sequencing batch biofilm reactors (SBBRs). The results indicated that a negative correlation was observed between SDBS concentration and the removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), and nitrate nitrogen (NO3−-N). Compared to the control group, their removal efficiencies were the lowest (decreases of 11.83 %, 12.15 %, and 8.11 %) when SDBS concentration was 1.67 mg (g MLSS) -1 (5 mg L−1). High-throughput sequencing showed that the abundance of Proteobacteria remained stable with SDBS addition, while the abundances of Patescibacteria and Actinobacteria decreased by 0.67–0.70 % and 0.69–3.06 %, respectively. Moreover, SDBS reduced both microbial diversity and richness and hindered the interspecific relationships among microorganisms. It also inhibited N metabolic activities and led to a decrease in the expression of key functional genes involved in N transformation (nifD, nifH, nasA, norB, norC, and nosZ). Additionally, the abundances of key enzymes (EC:1.7.99.1, EC:1.7.2.4, and EC:1.1.1.42) in the N and tricarboxylic acid (TCA) cycles decreased following the addition of SDBS. This study provided insights into the effects of SDBS on N removal in activated sludge-biofilm systems and the adaptive responses of microbial communities to SDBS exposure.

We are a spider’s web: Friendship in times of mental health crisis

Community responses to those experiencing mental health crisis and distress are important. However, in Australia and many other colonised countries, responses to distress have become highly medicalised, punitive, individual and privatised. Exploring friendship responses to mental health crisis may increase the possibilities for building on community connectedness and local support networks. The work described in this paper aimed to make visible the acts of care, solidarity, friendship and mutuality that friends and members of the community have taken up in response to someone close to them experiencing distress. The work was guided by intentional peer support and narrative practices including re-authoring, collective documentation and outsider witnessing.

Visualizing environmental change as inevitable, manageable, and deconstructive

ABSTRACT Working from a visual cultural approach that interrogates issues of visibility and visuality, this article theorizes how coastal residents represent their own observations and experiences of environmental change through photography and storytelling. We present results from an exploratory photovoice study in Maine, where participants framed change as an inevitable, manageable, or deconstructive process of social-ecological interaction. These results point to multiple, often contradictory ways participants understand and construct their environment and reveal the impact of their views on the perceived availability, desirability, and feasibility of community responses to change. In turn, the article presents critical implications for communication and dialogue about community development, resource management, and coastal adaptation.

Response of bacterial communities and soil chemistry to flood durations and recovery phases

Response of bacterial communities and soil chemistry to flood durations and recovery phases

Effects of warming on soil fungal community and its function in a temperate steppe

BackgroundThe potential effects of global warming on soil fungal communities and their functions remain uncertain. To address this issue, we investigated the effects of 3-year simulated field warming on the community and function of fungi in a temperate steppe of Inner Mongolia, northern China.MethodsThe diversity and structure of the fungal community were measured by high-throughput sequencing. The functionality of fungal communities was identified by comparison with the ITS reference database.ResultsOur results showed that warming did not affect the diversity of fungi, but significantly increased the complexity of the fungal community, with fungal taxa more closely associating with each other. We observed that plant pathogens and arbuscular mycorrhizal fungi were the most abundant functional groups. Meanwhile, warming significantly decreased the relative abundance of animal pathogens.ConclusionsWarming significantly increased the complexity of the fungal community, with soil pH being the main factor affecting soil fungal function. Our findings emphasize that the response of the fungal community and its functional groups to warming has significant implications for ecosystem biogeochemical cycling.