Ecological Implications Research Articles

Bioaccumulation of 137Cs: Vegetation Responses, Soil Interactions and Ecological Implications in the Northern Taiga Ecosystems.

This study presents the first comprehensive examination of 137Cs behavior in northern taiga ecosystems of the Kola Peninsula, a previously understudied region regarding radionuclide mobility. The background radioactive contamination of these ecosystems stems from global fallout and differs from more extensively studied contaminated areas. Twelve monitoring sites at varying distances from the Kola nuclear power plant were established to assess 137Cs accumulation in dominant plant species across three forest tiers. Gamma-spectrometric measurements revealed high mobility of 137Cs with specific activity ranging within 4.7-34.5 Bq/kg in trees, 8.4-164.8 Bq/kg in shrubs, and 15.0-94.5 Bq/kg in mosses. Notably, Ericaceae family plants demonstrated the highest accumulation capacity. 137Cs concentrations were significantly higher at the background site (30 km from the power plant) than in the sanitary protection zone, indicating no detectable influence from the nuclear facility. Strong correlations (up to |rs| = 0.93) between bioaccumulation indicators and soil properties were found-particularly with potassium content, exchangeable cation concentration, and organic matter content-suggesting that soil characteristics primarily determine 137Cs mobility. These findings highlight the potential risk of 137Cs movement through food chains in northern taiga ecosystems, with bioaccumulation coefficients exceeding those of central Russian landscapes and being comparable to those of Scandinavian taiga ecosystems.

Community awareness and the impact of invasive Indian house crows on lizard abundance and diversity in Dodoma, Tanzania

Invasive species such as the Indian House Crow (Corvus splendens) pose a significant ecological threat by disrupting local ecosystems and outcompeting native species. Originally from the Indian subcontinent, this crow has become invasive in Dodoma, Tanzania, where it preys on various organisms, including lizards. Lizards, which are important for pest control and as prey for higher trophic levels, are particularly affected. This study investigates community perceptions of Indian house crows and their impact on lizard populations in Dodoma. Using a combination of cross-sectional surveys and systematic sampling, we assessed local perceptions, lizard diversity and crow abundance. Our results show that approximately 85% of the community is aware of the presence and impact of Indian house crows. The study also shows that lizard diversity, as measured by Shannon's index, is higher in urban areas (1.51) with higher house crow abundance than in peri-urban areas (1.12). However, these urban areas also have significantly higher predation rates, with an average of 12% higher predation on lizards. The study highlights the ecological and socio-economic implications of house crow invasions and stresses the need for targeted management strategies to mitigate their negative impacts on local biodiversity and ecosystems.

Impact of Blastocystis carriage and colonization intensity on gut microbiota composition in a non-westernized rural population from Colombia.

The role of Blastocystis, a common intestinal parasitic protist of humans and other animals, in human health and disease remains elusive. Recent studies suggest a connection between Blastocystis colonization, healthier lifestyles, and high-diversity gut microbiota. Nevertheless, studies concerning the relationship between Blastocystis colonization, its intensity, and gut microbiota composition -involving both bacterial and eukaryotic communities- remain limited. This study examines the impact of Blastocystis carriage and colonization intensity on gut microbiota composition in a rural community in Colombia. A total of 88 human samples were collected from the rural population of Las Guacas village, located in the Cauca department in southwest Colombia. We utilized 16S and 18S rDNA sequencing to analyze both bacterial and eukaryotic microbiota, comparing Blastocystis-positive and -negative individuals, as well as groups with varying Blastocystis colonization intensity (low, medium, high), to identify distinct microbiota profiles and differentially abundant taxa linked to each condition. The analysis revealed significant differences between Blastocystis-positive and -negative individuals. In terms of bacterial composition and structure, Blastocystis-positive individuals exhibited distinct microbiota profiles, as shown by beta diversity analysis. Taxa associated with colonization included Bacteroides, Prevotella, Oscillibacter, Faecalibacterium, and Alistipes. Higher Blastocystis colonization intensity was associated with an increased abundance of taxa such as Alistipes and Lachnospira, while lower intensities correlated with beneficial bacteria such as Akkermansia. Regarding eukaryotic composition, beta diversity analysis revealed distinct profiles associated with Blastocystis colonization. Differentially abundant taxa, including Entamoeba coli, were more prevalent in Blastocystis-positive individuals, while Blastocystis-negative individuals exhibited a higher abundance of opportunistic fungi, such as Candida albicans. Machine learning models, including random forest classifiers, supported these findings, identifying Faecalibacterium and Bacteroides as predictors of Blastocystis colonization. These findings suggest that Blastocystis may modulate gut microbiota, contributing to microbial balance providing new insights into the ecological implications of Blastocystis in rural populations.

Prevalence and antimicrobial resistance profile of Listeria spp. isolated from raw fish

BackgroundListeria spp. contamination in food, particularly antimicrobial-resistant strains, poses an escalating concern for public health. This study investigated the prevalence and antimicrobial resistance profiles of Listeria spp. isolated from raw fish collected from diverse sources in Northern Poland.MethodsA total of 750 raw fish samples were collected from standing freshwater tanks, flowing freshwater reservoirs, and a saltwater reservoir. Isolation was performed following the standard protocol, which describes the horizontal method for detecting Listeria spp., including Listeria monocytogenes. The antimicrobial resistance profiles of isolated strains were performed using the disk diffusion method. Antimicrobial resistance genes were identified using PCR, targeting 11 genes associated with resistance to β-lactams, macrolides, glycopeptides, and sulfonamides. Statistical analyses included Phi correlation coefficients, hierarchical clustering, and logistic regression to examine associations between phenotypic resistance patterns and antimicrobial resistance genes.ResultsListeria spp. was isolated from 13.9% of samples (104 positive samples), comprising L. seeligeri (34.6%), L. welshimeri (28.8%), L. monocytogenes (23.1%), and L. innocua (13.5%). Phenotypic antimicrobial susceptibility testing revealed universal resistance to oxacillin (100%) across all Listeria spp. isolates. High resistance levels were also observed for cefotaxime (97.1%), cefoxitin (92.3%), rifampicin (92.3%), clindamycin (96.2%), and trimethoprim-sulfamethoxazole (91.3%). Alarmingly, 98.1% of all Listeria spp. isolates exhibited multidrug resistance (MDR), reaching 100% MDR among L. monocytogenes isolates. Specifically, L. monocytogenes isolates exhibited complete resistance to meropenem, cefoxitin, cefotaxime, rifampicin, and trimethoprim-sulfamethoxazole, and significant resistance to ciprofloxacin (91.7%), clindamycin (83.3%), tetracycline (75.0%), erythromycin (75.0%), benzylpenicillin (70.8%), and nitrofurantoin (70.8%). Molecular analysis identified blaTEM (100%), ampC (37.5%), and ereB (37.5%) as the most prevalent antimicrobial resistance genes in L. monocytogenes.ConclusionsThe exceptionally high prevalence of multidrug-resistant Listeria spp., particularly L. monocytogenes, in raw fish underscores a critical public health risk, suggesting the urgent need for ongoing surveillance and robust risk mitigation strategies in aquaculture and seafood processing. The elevated antimicrobial resistance levels may also indicate aquatic environmental contamination, warranting further investigation into the sources and broader ecological implications of antimicrobial resistance in these ecosystems.

Ecological Impacts of Pteridium aquililium and Chromolaena odorata Invasions in Rangelands of the Bamenda Highlands

Weeds are a growing threat to livestock rearing in the grazing lands of the Bamenda highlands. The ecology of grazing lands in the Bamenda highlands is in a convergent evolution with increasing weed invasion. The recent dynamics has seen the increasing invasion of two notable weeds notably Pteridium aquililium and Chromolaena odorata in the region with different ecological repercussions. The study set out to study the ecological implications of these two species of weed in the grazing landscape. A total of 64 cross section transects were studied in different topographic units across the region both in high plateau areas and lowland areas. Quadrats of 1x1m were laid in foot hills, slopes and top of hill. Information relating to grass species composition, relative abundance, weed species and ground cover was obtained through this field evaluation. Soil analysis from different samples collected across the area was also performed. Results revealed change in vegetation composition with an increase in weeds in composition, reduction in relative abundance for palatable species and shifts in species. There is a significant reduction in native species in densely infested C. odorata sites in the area. Moreover, most native species are absent where C. odorata is abundant, and species richness declines by nearly 72% from the margin to the center of the infestation. In Bracken infested areas where its canopies are quite closed, other weed are associated to its invasion in the undergrowth notably Emilia pratemisa, Taraxacum sp and Alchemilla Cryptantha. Species reductions in fern infested pastures are not as great as C. odorata stands although Pteridium aquililium creates more continuous extensive patch sizes of monospecific stands than C. odorata discontinuous dense stands. Shifts and species reduction due to invasions reached 61%. Species shifts mostly concern Setaria sp. (S. sphacelata), Loudetia and Panicums on the better soils and with Andropogon, Paspalum and Imperata of medium size on the poorer soils. Fuel loads increase and modify fire regimes creating post fire succession species. Management require concerted actions among actors to curb invasions.

The effect of early life thermal environment on morphology and growth of yellow perch (Perca flavescens).

Early life development in fishes is a period of high phenotypic plasticity. Water temperatures during embryogenesis can lead to alterations in growth and metabolic and morphological phenotypic variations. This study aimed to characterize the effects of temperature on the growth and morphology of yellow perch throughout early development, a species of significant ecological and economic importance in North America. Yellow perch (Perca flavescens) embryos were incubated at either constant temperature (12, 15, or 18°C) or under an ambient seasonal regime, where temperature increased throughout embryogenesis until it reached 18°C. All groups were gradually warmed at hatch until they reached 18°C, and morphology was assessed. Inverse relationships between temperature, length and yolk-sac volume were found at the end of the embryonic period. Optimal embryonic growth was associated with the ambient seasonal regime. Fish reared at 15 or 18°C were larger and had higher growth rates when compared to those at 12°C following hatch. However, fish reared in cooler temperatures may possess more advantageous body shapes. Surprisingly, the ambient seasonal incubation had the lowest growth rate post-hatch, even though this most closely mimicked natural incubation for this species. Because suitable larval morphology is related to survival and successful recruitment, these data suggest that yellow perch may be vulnerable to climate change and thermal pollution, although further work is needed to better predict the ecological implications of the phenotypes.

Assessing the heavy metal contamination and health risks in riverine sediments using multi-index analysis: insights from east coast of Tamil Nadu, India.

The research article appraises the environmental pollution status and health risk assessments associated with heavy metal concentration in the Gadilam (study site I) and Uppanar (study site II) river surface sediments within the quaternary formation, part of Kallakurichi and Cuddalore district, Tamil Nadu, India. By analyzing the heavy metal concentration and environmental pollution zone and health risk assessments, the outcome fosters the insights of an intensifying risk to riverine regions and their ecological implications due to anthropogenic activities. Totally 27 sediment samples were collected from study sites I and II to assess the contagion status of the sediments and monitor the riverine environment. Heavy metal (Fe, Al, Ti, Mn, Cu, Zn, Ni, Pb, and Cr) concentrations were determined in surface sediments, addressing the influences arising from anthropogenic activities. To decipher the pollution status, the pollution monitoring indices, like geoaccumulation indices (Igeo), enrichment factor (Ef), contamination factor (Cf), degree of contamination (Cd), and modified degree of contamination (mCd), pollution load index (PLI), potential ecological risk indices (PERI), and sediment quality guidelines (SQGs) such as mean effects range median quotient (MERMQ), toxic risk index (TRI), and modified hazard quotient (mHQ), were used in the study area. Health hazard assessment stated non-carcinogenic risk and carcinogenic risk were analyzed for adults and children in study sites I and II. Subsequently, statistical analysis were performed. The outcome possessed the pollution assessment of study site I (location - 05 and 06) and study site II (location-03), which implies that they are extremely polluted and have high potential adverse biological effects. This study emphasized the non-carcinogenic risk assessment of hazard index (HI) for study sites I and II sediments shown to be endangered to adults and children in the surrounding region. Furthermore, the carcinogenic risk assessment accounted for no hazards for adults and children in the study site. This study revealed heavy metal contamination in the Cuddalore district, likely arising from industrial effluents, residential wastages, and anthropogenic activities in the surface sediments of riverine environment, and it provide insights into health risk assessment and environmental pollution status to foster the local communities' awareness and an invaluable dataset to generate environmental safety management measures.

Examining the success possibility of sustainable manufacturing adoption in Indian textile organizations: ecological, societal, cutting-edge technologies and future generations implications

Examining the success possibility of sustainable manufacturing adoption in Indian textile organizations: ecological, societal, cutting-edge technologies and future generations implications

Acclimation to white light in a far-red light specialist: insights from Acaryochloris marina MBIC11017.

The Chl d-containing cyanobacterium, Acaryochloris marina MBIC11017, is constitutively adapted to far-red light (FRL). However, it occasionally encounters white light (WL) in its natural habitat. Using biochemical and spectroscopic techniques, we investigated how this organism acclimates to WL and analysed the excitation energy trapping dynamics of its photosystems and complex antenna system, comprised of both membrane-embedded and soluble antenna. When grown in WL, A. marina MBIC11017 doubles its Photosystem I/Photosystem II (PSI/PSII) ratio and increases its phycobilisome content compared with FRL, without altering their composition, while the number of membrane-embedded antennae decreases. Under both light conditions, phycobilisomes primarily transfer excitation energy to PSII, but a smaller fraction transfers to PSI. The PSI trapping time is fast (35 ps), confirming the absence of red-shifted forms. By contrast, PSII trapping is slower, with two components of c. 115 and c. 480 ps. Simulations based on the PSII structure suggest that this slow trapping arises mainly from the PSII antenna arrangement rather than from the use of Chld as a primary donor. These results reveal how A. marina MBIC11017 dynamically adjusts photosystem ratios and antenna composition to changes in light quality, offering insights into the ecological and functional implications of Chld-driven photosynthesis and chromatic acclimation.

Filth and the city

Filth is a material and a semiotic category that has long been used to classify and govern the human and the nonhuman world. Undesired social groups and forms of life are elided with disgusting elements of the environment to justify their suppression or eradication. The science and the management of filth have been central to modernity and have profoundly shaped urban life. The rise of microbiology revealed the microbial origins of some diseases, empowering visions of the sanitary city in both the metropole and the colony. This drove substantial investments in sanitation, hygiene, and the removal of animals and agriculture. However, recent research on the human microbiome has demonstrated the salutary role of some microbes for human well-being. It highlights the value of forms of material previously categorized as filth and calls for a recalibration of modern, antibiotic hygiene practices and modes of architecture and urban planning. This new microbiology is driving a nascent, probiotic turn in urban theory that overlaps with a wider appreciation of the beneficial role of nature in the urban environment, and the development of more affirmative models of urban hospitality premised on living with social difference. This review and perspective examines these connected developments, explores their implications for urban political ecology, and outlines a new research agenda. It starts with a chronology of the shifting material and semiotic relationships with filth in science and society, before identifying six key research questions to guide an interrogation of this new chapter in the storied history of filth and the city.

Long-term spatio-temporal analysis of red tides in Hong Kong and their environmental drivers and ecological implications.

Long-term spatio-temporal analysis of red tides in Hong Kong and their environmental drivers and ecological implications.

Ecological risk assessment and ingestion of microplastics in edible finfish and shellfish species collected from tropical mangrove forest, Southeastern India.

Ecological risk assessment and ingestion of microplastics in edible finfish and shellfish species collected from tropical mangrove forest, Southeastern India.

Episodic memory and reproductive condition could independently influence the pair bond maintenance in the male prairie vole (Microtus ochrogaster): Ecological implications and translational relevance in the study of sub-clinical manifestations of schizophrenia.

Episodic memory and reproductive condition could independently influence the pair bond maintenance in the male prairie vole (Microtus ochrogaster): Ecological implications and translational relevance in the study of sub-clinical manifestations of schizophrenia.

Understanding arbuscular mycorrhizal fungi's contribution to hexabromocyclododecane metabolism: Pathways and ecological implications in contaminated environments.

Understanding arbuscular mycorrhizal fungi's contribution to hexabromocyclododecane metabolism: Pathways and ecological implications in contaminated environments.

Culture and conservation in baleen whales.

Culture, defined as information or behaviours shared within a population and acquired from conspecifics through social learning, acts as a second inheritance system which has important implications for species' ecology and evolution. Understanding the influence of social learning and culture in animals' lives is essential to planning and predicting outcomes of conservation actions. Culture plays a key role in cetaceans' lives, and some of the best evidence for social learning has come from baleen whales (Mysticetes). The Convention on the Conservation of Migratory Species of Wild Animals (CMS), an international treaty operating under the United Nations Environment Programme (UNEP), has recently integrated animal culture into their conservation initiatives. An essential first step in such a conservation framework is to identify key indicators of social learning in well-studied species, which could be applied to other more elusive species. Here, as part of the UNEP CMS Expert Group on Animal Culture and Social Complexity, we first evaluate key evidence for social learning and culture in baleen whales through several case studies. We then suggest key indicators by behavioural context to assist in identifying potential cases of social learning in more elusive species generating a practical guide for future conservation assessment and management.This article is part of the theme issue 'Animal culture: conservation in a changing world'.

Early Miocene ventricose bamboo from south Asia with implications for evolutionary ecology and biogeography.

Early Miocene ventricose bamboo from south Asia with implications for evolutionary ecology and biogeography.

Polyaromatic hydrocarbons (PAHs) in surficial sediments of Ashtamudi wetland: Dissemination, source apportionment, ecological and public health implication

Polyaromatic hydrocarbons (PAHs) in surficial sediments of Ashtamudi wetland: Dissemination, source apportionment, ecological and public health implication

Spatiotemporal dynamics of microcystin contamination in fish across the Lake Chaohu basin under the Yangtze River ten-year fishing ban: Ecological and human health implications.

Spatiotemporal dynamics of microcystin contamination in fish across the Lake Chaohu basin under the Yangtze River ten-year fishing ban: Ecological and human health implications.

Chlorantraniliprole-induced oxidative stress, DNA damage, and apoptosis in Caenorhabditis elegans: Mechanistic insights and ecological risk implications.

Chlorantraniliprole-induced oxidative stress, DNA damage, and apoptosis in Caenorhabditis elegans: Mechanistic insights and ecological risk implications.

Emerging genetic diversity of Mycoplasma gallisepticum in Mexican house finches: Evidence of possible independent spillover events.

Emerging genetic diversity of Mycoplasma gallisepticum in Mexican house finches: Evidence of possible independent spillover events.