Anthropogenic Pressures Research Articles

Environmental DNA metabarcoding reflects spatiotemporal fish community shifts in the Scheldt estuary.

Estuarine ecosystems face increasing anthropogenic pressures, necessitating effective monitoring methods to mitigate their impacts on the biodiversity they harbour. The use of environmental DNA (eDNA) based detection methods is increasingly recognized as a promising tool to complement other, potentially invasive monitoring techniques. Integrating such eDNA analyses into monitoring frameworks for large ecosystems is still challenging and requires a deeper understanding of the scale and resolution at which eDNA patterns may offer insights in species presence and community composition space and time. The Scheldt estuary, characterized by its diverse habitats and complex currents, is one of the largest Western European tidal river systems. Until now, it remains challenging to obtain accurate information on fish communities living in and migrating through this ecosystem, consequently confining our knowledge to specific locations. To explore the potential of eDNA based monitoring, we simultaneously combine stow net fishing with eDNA metabarcoding, to assess spatiotemporal shifts in the Scheldt estuary's fish communities. In total, we detected 71 fish species in the estuary using eDNA metabarcoding, partly overlapping with historic fish community data gathered at the different study locations and in contrast to only 42 species using stow net fishing during the same survey period. Community compositions found by both detection methods varied among sampling locations, driven by a clear correlation to the salinity gradient. Limited effects of sampling depth and tide were observed on the eDNA metabarcoding data, allowing a significant reduction of the eDNA sampling effort for future eDNA fish monitoring campaigns in this study system. Our results further demonstrate that seasonal shifts in fish species occurrence can be detected using eDNA metabarcoding. Combining eDNA metabarcoding and stow net fishing further enhances our understanding of this vital waterway's diverse fish populations, allowing a higher resolution and more efficient monitoring strategy.

Variable effects of captivity on microbiomes in populations of IUCN-endangered Blanding's turtles (Emydoidea blandingii).

Microbiome composition is increasingly considered in species reintroduction efforts and may influence survival and reproductive success. Many turtle species are threatened by anthropogenic pressures and are frequently raised in captivity for reintroduction efforts, yet little is known about turtle microbiome composition in either wild or captive settings. Here, we investigated trends in microbiome composition of captive and wild IUCN-endangered Blanding's turtles (Emydoidea blandingii). We amplified and sequenced the V4 region of the 16S rDNA locus from plastron, cloaca, and water samples of wild E. blandingii adults and two populations of captive E. blandingii juveniles being raised for headstarting. Plastron, cloaca, and water-associated microbiomes differed strongly from each other and were highly variable among captive sites and between captive and wild sites. Across plastron, cloaca and water-associated microbial communities, microbial diversity changed over time, but not in a predictable direction between captive sites. Plastron beta diversity correlated with growth rate in captive samples, indicating that external microbiomes may correlate with individual fitness. Our results indicate that external and internal microbiomes vary between captive and wild turtles and may reflect differences in fitness of captive-raised individuals.

Identifying protected areas in biodiversity hotspots at risk from climate and human-induced compound events for conserving threatened species.

Anthropogenic pressure in areas of biodiversity importance erodes the integrity of the ecosystems they harbour, making features of biodiversity less buffered against extreme climatic events. We define the combination of these disturbances as compound events. We assessed compound event risk in protected areas (PAs) applying a spatial framework guided by criteria and quantitative thresholds associated with exposure to cyclones, drought, and intense human pressure. This assessment was used in a relational matrix to classify PAs with different risk of compound event occurrence. We identified PAs of higher conservation concern by quantifying the extent of human pressure in their surrounding landscape while harbouring large numbers of threatened vertebrate species. Of the 39,694 PAs assessed, very high risk of compound events was determined for 6965 PAs (17.5 %) related to cyclones and human pressure (mainly island hotspots), 6367 PAs (16 %) related to droughts and human pressure (island and continental hotspots), and 2031 PAs (5 %) to cyclones, drought and human pressure (mainly in island hotspots). From the subset of 2031 PAs assessed at very high risk, we identified 239 PAs of higher conservation concern distributed predominantly in the Caribbean Islands, Japan, North America Coastal Plain, Philippines, and Southwest Australia. Our work highlights PAs in the biodiversity hotspots where high risk of compound event occurrence poses a greater threat to species. We encourage researchers to adapt and apply this framework across other globally significant sites for conserving biodiversity to identify high risk-prone areas, and prevent further biodiversity decline.

Occurrence and temporal activity pattern of Burmese Red Serow (Capricornis rubidus, Bovidae) in Baraiyadhala National Park, Bangladesh: insights from a camera trapping study

Abstract No single studies on the Burmese Red Serows, a little known bovid to date yet considered as nationally endangered species, have been conducted in Bangladesh. As part of a systematic wildlife inventory and monitoring project, this study utilized 48 camera traps to elucidate their occurrence, activity pattern and possible sympatric association with other artiodactyls species inhabiting Baraiyadhala National Park. The study found 25 independent serow events with relative abundance index (RAI) of 0.89. The number of individuals seems low, but this is by far the country’s stronghold population. The Red Serows are mostly nocturnal and showed moderate temporal activity with barking dear (∆1 = 0.59) and wild boar (∆1 = 0.62) in this area. Anthropogenic pressures due to tourists (RAI = 4.8) and poachers (RAI = 1.7) were highly evident and must have negative impact on overall wildlife of the national park. The study suggests similar studies in adjacent protected area (Hazarikhil Wildlife Sanctuary), habitat protection and restoration program, and awareness raising program targeting forest dependent communities for long term conservation of this species.

Measurement of fisheries provisioning services and its pressure to support sustainability of fisheries in the Jatigede Reservoir, Indonesia

Jatigede Reservoir is a newly inundated reservoir in Sumedang Regency, West Java. Jatigede Reservoir provides ecosystem services in the form of aquatic organisms as food for the surrounding community. The lack of research related to ecosystem services in Jatigede Reservoir, and there has been no research related to the method of measuring the status of fisheries provisioning services, makes this article focused and aims to determine the status of ecosystem provisioning services in the fisheries sector and elaborate anthropogenic pressures. The results obtained in this study are the status of provisioning services getting 2.2 points which means the status is in the moderate class. The anthropogenic pressure obtained is in the form of residual waste from the floating net cage, trash or waste sent from rivers that enter the Jatigede Reservoir, residual oil and boat oil waste, and domestic waste in the form of metabolic waste (urine and feces) and residual oil food and leftover soap from people working and doing activities in the waters. This data is needed for making strategies and a policy for the sustainability of fisheries in Jatigede Reservoir.

Implementation of a Far-Field Water Quality Model for the Simulation of Trace Elements in an Eastern Mediterranean Coastal Embayment Receiving High Anthropogenic Pressure

Water quality modeling is a key element for the support of environmental protection and policymaking. The aim of this work is to describe the application of a far-field water quality model for the simulation of marine pollution occurring from heavy metals (cadmium, lead, nickel, copper, and zinc). The highly stressed marine area of the Saronikos Gulf (Aegean Sea, Eastern Mediterranean) was chosen for investigation. Major pollution sources were identified, loads were estimated, and the model was parameterized to reproduce the local seawater conditions. The distribution of the pollutants between the dissolved and particulate phases was examined. The performance of the model set-up was evaluated using field concentration measurements. The described implementation succeeded in reproducing the observed levels of pollution and therefore can be used as a baseline configuration to examine the cumulative impact of future pollution sources; for example, accidental pollution events.

Assessing ecosystem services of mountain lakes

From global to local scales, human-induced environmental changes can impact mountain lakes by, for example, altering species composition, trophic state, and thermal dynamics, thereby affecting ecosystem functions and processes. However, the consequences of these changes on ecosystem services (ES) of mountain lakes are unclear due to a lack of integrative assessments. Therefore, this dissertation adopts an interdisciplinary ES perspective to improve insight into human interactions with mountain lakes and the potential social and ecological impacts of anthropogenic pressures on them. Stakeholder consultations highlighted the importance of regulating, cultural, and provisioning ES of natural mountain lakes, emphasizing habitat, aesthetics, recreation, education and research, and surface water, with nature-based experiences as being a key aspect of human interaction with mountain lakes. Multiple indicators were proposed to quantify potential supply of these ES, revealing variations among case study lakes in the European Alps. These results informed an integrative valuation approach and exposure assessment to anthropogenic pressures, suggesting that ES by mountain lakes are sensitive to climate change-related and human use pressures. Overall, the findings advance a social-ecological understanding of mountain lakes and indicate towards the need for adaptive lake management to maintain ES under potential anthropogenic pressure.

Oceanographic Research in the Thermaikos Gulf: A Review over Five Decades

The Thermaikos Gulf (TG) is a semi-enclosed, river-influenced, marine system situated in the eastern Mediterranean Sea, sustaining both urban coastal regions and ecologically preserved natural areas. Facing a plethora of environmental and anthropogenic pressures, the TG serves as a critical nexus where human activities intersect with marine ecosystems. The quality and health of the TG’s marine environment are tightly linked to the socioeconomic activities of the coastal communities comprising approximately 1.5 million inhabitants. The main features of the TG’s environmental dynamics and ecological status have been scrutinized by dedicated research endeavors during the last 50 years. This review synthesizes the seminal findings of these investigations, offering an evaluation of their contribution to research, their present collective impact, and their trajectory toward the future. A severe deterioration of the TG’s environmental quality was detected in the 1970s and 1980s when the treatment of urban wastewater was completely absent. A steady trend of recovery was observed after the 1990s; however, so far, the goal of a “good environmental state” mandated by national legislation and European directives has not been achieved. A clear reduction in research was detected after 2010, associated with the recession of the Greek economy, following the “golden period” for research in the TG from the mid-1990s until the late 2000s. The most important research gaps and uncertainties are discussed, while specific targeted recommendations for the improvement of monitoring and understanding of the physical, biochemical, and ecological state of the gulf are provided: (i) increase in permanent observational stations (temporally and spatially); (ii) inclusion of all major environmental parameters; (iii) monitoring of the quantity and quality of all land-originated freshwater discharges; (iv) monitoring and management of important aspects of the marine environment that have received minimal attention in the past (e.g., coastal erosion, plastic pollution); (v) development of accurate prediction tools (e.g., numerical techniques) to support first-level responders and efficient management; (vi) establishment of a supervising public entity that would support the holistic overview and management of the entire TG. These suggestions are directed at overcoming the existing uncertainties in the knowledge of the TG, safeguarding its ecological integrity and its role as a crucial link to marine biodiversity and sustainability in the Mediterranean basin.

Decrease in fertility of typical chernozem due to long-term anthropogenic pressure in grain-beet crop rotations

The saturation of sugar beet rotations under different fertilizer application systems and long-term cultivation induces significant changes in soil properties, leading to decreases in humus content, mineral nitrogen, phosphorus, and potassium. The study was conducted in a stationary multifactorial experiment in grain-beet crop rotations: crop rotation, row-crop, and grain-row crop rotations with the application of 40 t/ha of manure under sugar beets + NPK 100:90:90 and a variant without fertilizers. The paper presents the results of monitoring changes in humus content during each rotation, reduction of humus reserves in the plow layer, and physicochemical and agrochemical soil indicators. In the variants without fertilizers, we observed 0.24–0.41% decline in humus content in all crop rotations during 3 rotations of ten-field crop rotations (30 years). Overall, there occurred 0.89–1.00% decrease over 50 years of anthropogenic influence, equivalent to 31.8–35.7 t/ha, or 23.1–26.1% of initial reserves per hectare. Despite application of 40 t/ha of manure + NPK 100:90:90 under sugar beets, humus loss was 27.5 t/ha in the row-crop rotation and 16.8 t/ha in the grain-row crop rotation. Fertilizer application led to increase in exchangeable and hydrolytic soil acidity. With the application of 6.7 t/ha of manure + NPK 53:42:42 per 1 ha of crop rotation area, there was a tendency towards increase in mineral nitrogen content, mobile phosphorus doubled to 280.1–302.8 mg/kg compared to the variant without fertilizers, and exchangeable potassium decreased regardless of the fertilization system, which was associated with its utilization by plants. Sugar-beet yield increased to 44.76 t/ha in the crop-rotation under the organo-mineral-fertilizer application system, exceeding the spring wheat rotation by 4.63 t/ha and the variants without fertilizers by 2.45–2.72 times. Therefore, the modern fertilizer application system under sugar beets did not ensure stabilization of humus content in the soil and increased its acidity. It is necessary to more broadly use cover crops in crop rotations, incorporate crop residues, and apply biological preparations to improve soil fertility.

Ecology and behaviour of the invasive lionfish Pterois miles colonizing coastal areas of the central Mediterranean

Biodiversity redistribution is occurring at an unprecedented pace, with one prominent example being the invasion of the lionfish (Pterois miles) in the Mediterranean Sea, altering the fish community composition by creating novel interspecific interactions and potentially threatening local biodiversity. Our study attempts to identify patterns in the lionfish distribution and behaviour in the coastal zone of the eastern Ionian Sea (central Mediterranean). Over a 14-month period, visual censuses were conducted along coastal strip transects at six stations, situated in three areas (Mani, Katakolo, Astakos) across a latitudinal gradient. Lionfish density was highest in Mani, the southernmost area. Higher densities were found at two stations experiencing direct anthropogenic pressures: one with structural modifications by port infrastructure, and the other in the vicinity of a fish farm, indicating a potential role of human interventions in facilitating the establishment of invasive populations. Lionfish group size was influenced by overall density, exhibiting variation between the two natural stations. Lionfish activity levels by microhabitat were site-specific, with more inactive individuals in crevices. Temporal activity patterns were similar in the natural stations, with increased activity during spring and summer months; however, temporal activity patterns were not identical in the two anthropogenic sites, suggesting that the specific nature of anthropogenic intervention might possibly influence lionfish activity. Finally, lionfish densities were not significantly different between early morning and late afternoon times of day, in agreement with the crepuscular behaviour already documented for this species.

Copepod distribution and diversity in the coastal areas of Ban-ao and Lambajon, Davao Oriental, Philippines: Environmental influences and conservation implications

Copepods are essential components of marine ecosystems, facilitating energy transfer within these complex systems. The study investigates copepod diversity and distribution in Ban-ao and Lambajon coastal areas in Baganga, Davao Oriental, highlighting the environmental factors influencing copepod populations. Four copepod families representing different orders were identified, with Harpacticoida, Calanoida, and Cyclopoida prevalent in both sites, while Misophrioida was exclusive to Lambajon. Physico-chemical parameters such as dissolved oxygen (DO), pH, salinity, sediment composition, water depth, and temperature were analyzed to understand their correlation with copepod density. The study reveals variations in copepod density and abundance between the sites, with Lambajon showing a higher total density (49 ind/cm³) compared to Ban-ao (35 ind/cm³). The Pearson correlation matrix illustrates complex relationships between copepod density and environmental parameters in each site. In Ban-ao, strong positive correlations were found between copepod density and DO (r = 0.65) and temperature (r = 0.36). In Lambajon, positive correlations existed between water depth and copepod density (r = 0.20). Both sites exhibit low copepod diversity overall, potentially due to anthropogenic pressures. These findings emphasize the need for further research to understand the interactions between environmental factors and copepod diversity, essential for effective conservation and management strategies in these coastal ecosystems.

One-year monitoring of potentially pathogenic microorganisms in the waters and sediments of the Lesina and Varano lagoons (South-Est Italy)

In this study, two Mediterranean coastal lagoons (Lesina and Varano) of Southern Italy, located in the north of the Apulia region, were investigated for the presence of Shiga toxin Escherichia coli (STEC) and potentially enteropathogenic Vibrio species in parallel with norovirus (NoV), hepatitis A virus (HAV), hepatitis E virus (HEV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to evaluate the presence of potentially pathogenic bacteria and viruses in the water and sediments of these ecosystems. From March 2022 to February 2023, a total of 98 samples were collected: 49 water samples and 49 sediment samples. STEC strains were isolated in three samples (3.1%), of which one (2%) was water (stx1 and stx2 positive) and two (4.1%) were sediment (both stx2 positive) samples. Vibrio spp. were detected in twenty samples (20.4%), of which nine were water (18.4%) and eleven were sediment (22.4%) samples. The species detected included V. parahaemolyticus, V. cholerae, and V. vulnificus. NoV was detected in 25 (25.5%) samples, while none of the water or sediment samples were positive for HAV, HEV, and SARS-CoV-2. The results of this study provide an overview of the presence of potentially pathogenic microorganisms in areas influenced by anthropogenic pressure. Monitoring the circulation of these pathogens could be useful to evaluate the water flowing into the lagoons, in particular discharge waters (i.e., urban, agricultural, and livestock runoff), considering the presence of fish and shellfish farms in these sites.

Is the past recoverable from the data? Pseudoproxy modelling of uncertainties in palaeoecological data

Is the past recoverable from the data? Pseudoproxy modelling of uncertainties in palaeoecological data

Biocentric Work in the Anthropocene: How Actors Regenerate Degenerated Natural Commons

AbstractAs natural commons vital to selves, organizations, and institutions collapse under cumulative anthropogenic pressures, can human agency still reverse some of the damage already done? This article explores how emerging forms of social symbolic work regenerate degenerated natural commons. Using a five‐year multi‐sited immersive ethnography of natural commons that had collapsed, we explain how actors (re)turn to the biophysical roots of socio‐ecological systems to take care, work with, and care for nature. We show how actors’ comprehension develops over time by connecting their social‐symbolic construction of natural commons post collapse with three sets of practices we label biomanipulation, biofacilitation, and bioaffiliation. We inductively theorize biocentric work as a processual form of social‐symbolic work that connects three cycles of material abduction, relational intercession, and discursive grounding. Our tri‐cyclical process model underscores the biophysical foundations of social‐symbolic work in the Anthropocene by explicitly and iteratively situating self, organizations and institutions in the states and dynamics of natural commons.

Variation in macroinvertebrate assemblages and water quality as a test for different levels of ecological impairment across an Ethiopian highland river system

The Ethiopian highlands is an area under high anthropogenic pressure. Despite being a hotspot for freshwater biodiversity, there is no regular monitoring of the ecological status of local rivers. Physicochemical and nutrient water-quality parameters and macroinvertebrate assemblages were sampled monthly from the Megech River and its tributaries from January to March 2021. Sampling locations were designated as being either upstream or downstream of the Gondar City urban area. We tested for temporal (monthly) and spatial (location, river) variation in water quality and spatial (location, river) variation in macroinvertebrate assemblage structure, and examined which water quality parameters were most associated with patterns in macroinvertebrate assemblages. Water quality varied significantly between locations and months, but not between rivers. Water quality differences were particularly driven by higher nutrient, salinity, dissolved solids and conductivity levels downstream, and higher pH and dissolved oxygen levels upstream. Despite macroinvertebrate assemblages being more abundant and diverse downstream, biotic index scores generally indicated slightly increased ecological impairment downstream. There was a clear spatial pattern in macroinvertebrate assemblages between locations. We detected a significant difference between rivers, with pairwise differences between sampling locations, particularly due to high dissimilarity between the upstream and downstream locations of the Angereb, Shinta and Qeha rivers. BIO-ENV Pearson correlations indicated that variation in macroinvertebrate assemblages were mostly explained by dissolved oxygen, salinity and nutrient parameters including nitrate, ammonium, and sulphate. Our findings confirm the need for more rigorous monitoring of Ethiopian highland rivers and improved management of nutrient inputs.

Elevated Fungicide and Nutrient Concentrations Change Structure but not Function of Aquatic Microbial Communities.

Leaf decomposition is a key process in stream ecosystems within forested catchments; it is driven by microbial communities, particularly fungi and bacteria. These microorganisms make nutrients and energy bound in leaves available for wider parts of the food web. Leaf-associated microorganisms are subjected to anthropogenic pressures, such as the increased exposure to nutrients and fungicides associated with land-use change. We assessed the sensitivity of leaf-associated microbial communities with differing exposure histories, namely, from pristine (P) streams, and streams impacted by wastewater (W) and agricultural run-off (vineyards; V). In the laboratory, microbial communities were exposed to elevated nutrient (NO3-N: 0.2-18.0 mg/L, PO4-P: 0.02-1.8 mg/L) and fungicide concentrations (sum concentration 0-300 µg/L) in a fully crossed 3 × 4 × 4-factorial design over 21 days. Leaf decomposition and exoenzyme activity were measured as functional endpoints, and fungal community composition and microbial abundance served as structural variables. Overall, leaf decomposition did not differ between fungicide treatments or exposure histories. Nonetheless, substantial changes in the fungal community composition were observed after exposure to environmentally relevant fungicide concentrations. Elevated nutrient concentrations assisted leaf decomposition, and the effect size depended on the exposure history. The observed changes in the fungal community composition support the principle of functional redundancy, with highly efficient decomposers maintaining leaf decomposition. Environ Toxicol Chem 2024;00:1-12. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

CA-Markov prediction modeling for the assessment of land use/land cover change in two sub-basins of the Tocantins-Araguaia River Basin.

Due to the anthropogenic pressures of expansion areas for livestock and agricultural production in the Brazilian Cerrado, it is of paramount importance to understand the dynamics of land use/land cover (LULC) changes in this region. Thus, we investigated LULC changes in two sub-basins of the Tocantins-Araguaia River basin from 1997 to 2015 and consequently projected future changes for the timespan between 2030 and 2050. The Formoso sub-basin experienced significant expansion of agricultural and pasture areas, whereas the Sono sub-basin limited farmland expansion (more stable native vegetation) due to substantial protected areas, trends that were also observed for future projections (2030 and 2050). Pastureland in the Formoso sub-basin increased by 5.8%, while the Sono sub-basin saw significant gains in cultivated land, according to change detection analyses during the 1997-2015 period. High stability probabilities of no change (> 70%) for grassland areas in the Sono River sub-basin and pasturelands in the Formoso River sub-basin were computed. The CA-Markov model demonstrated a high consistency level with actual LULC classes for both sub-basins, as indicated by an overall Kappa coefficient above 0.8. Future projections for 2030 and 2050 show a substantial expansion of agriculture and pasture in both sub-basins, driven by specific factors such as soil organic carbon stocks, distance from rural settlements, and proximity to rivers. Short- and mid-term simulations indicate substantial expansion of agriculture and pasture in both basins, with potential adverse impacts on water erosion. Consequently, developing policies for soil management and sustainable land use planning is essential for agroecosystem sustainability, promoting a balanced approach to economic development while addressing climate change and anthropogenic challenges.

Century‐Long Records of Sedimentary Input on a Caribbean Reef From Coral Ba/Ca Ratios

AbstractCoral reef ecosystems are delicately balanced and are thus prone to disruption by stressors such as storms, disease, climate variability and natural disasters. Most tropical coral populations worldwide are now in rapid decline owing to additional anthropogenic pressures, such as global warming, ocean acidification and a variety of local stressors. One such problem is the addition of excess sediment and nutrients flux to reefs from increased soil erosion from land use changes. Here we present century‐long Ba/Ca records from two Siderastrea siderea colonies as a proxy for local riverine discharge and sediment flux to the southern Mesoamerican Barrier Reef System (MBRS). The coral colonies have linear extension trends, which can be seen as a first‐order indicator for coral health and response. The coral colony that exhibits a decline in linear extension rate from the forereef of the MBRS, mainly receives riverine input from Honduras, whilst the coral from the backreef, which does not exhibit a decline in extension rate, primarily receives riverine input from more sparsely populated regions of Belize. Coral Ba/Ca increased (>70%) through time in the forereef colony, while the backreef colony showed little long‐term increase in Ba/Ca over the last century. Our results suggest that increasing sediment supply may have played a role in the decline of forereef skeletal extension in the southernmost MBRS region, likely stemming from increasing land‐use changes in Honduras.

An assessment of microplastic contamination in beach sediment of Maharashtra State, India, with special reference to anthropogenic activities.

The escalating issue of microplastic (MP) pollution poses a significant threat to the marine environment due to increasing plastic production and improper waste management. The current investigation was aimed at quantifying the MP concentration on 25 beaches on the Maharashtra coast, India. Beach sediments (1kg) were collected from each site, with five replicates to evaluate the extent of MPs. The samples were homogenized, and three 20 g replicas were prepared for subsequent analysis. Later, the samples were sieved, and MPs were extracted using previously published protocols. The abundance of MPs found as 1.56 ±0.79 MPs/g, ranges from 0.43 ±0.07 to 3±0.37 MPs/g. Fibers were found as the most abundant shape of MPs. Size-wise classification revealed dominance of <1mm and 1-2mm-sized MPs. Blue- and black-colored MPs were recorded dominantly. Polymer identification of MPs revealed polyurethane, polypropylene, polyvinyl chloride, acrylic or polymethyl methacrylate, and rubber. The findings revealed that MPs were found to be higher at highly impacted sites, followed by moderately impacted sites and low-impacted sites, possibly due to a different degree of anthropogenic pressure. The study recommended the urgent need for effective policy to prevent plastics accumulation in the coastal environment of Maharashtra State, India. PRACTITIONER POINTS: The study investigated the abundance and distribution of microplastics in the marine environment, specifically in sediments. The most common type of microplastic found was fibers, followed by fragments and films. Microplastics were found to pose a potential risk to the marine ecosystem, although further research is needed to fully understand their ecological impact. Future research should focus on expanding the sample size, assessing long-term effects, exploring sources and pathways, and considering size and shape of microplastics. The findings recommended urgent action to mitigate plastic pollution in Maharashtra coast.

Testing the applicability of the Modelling-Ongrowing fish farms-Monitoring B (MOM-B) investigation system for assessing benthic habitat quality in the Manila clam Ruditapes philippinarum aquaculture areas

The coastal aquaculture areas have been subject to a variety of anthropogenic pressures in recent studies, and reasonable environmental quality assessment is essential for both ecological conservation and production practices. However, there are significant differences between the results produced from various environmental quality assessment regarding the focus of the evaluation and the fundamental methodology. Furthermore, many of these methods are very specific and difficult to adapt to general applications. Here, we utilized the Modelling-Ongrowing fish farms-Monitoring B investigation system (MOM-B), we assessed the benthic habitat quality of benthic bivalve aquaculture areas in the Xiaoqing River estuary located in Laizhou Bay, China. The aim was to validate the accuracy and practicality of this system. The biological, chemical, and sensory parameters of the MOM-B system, temperature, chlorophyll a (Chl-a), food availability, and planktonic larvae were evaluated throughout the investigation area during the summer of 2021. The MOM-B results indicated that the benthic habitat quality in the survey area was good and lightly disturbed, but the quality in the middle tide area began to deteriorate in August, the hottest month of the summer. Environmental factors indicated that the combined effects of high temperatures and fine sedimentation had led to increased environmental stress in the middle tide area. Food availability and population recruitment also suggested that the benthic habitat quality was better in the high tide and low tide areas than in the middle tide area, and more favorable for the survival of Manila clams. The accuracy, sensitivity, and discriminatory ability of the MOM-B system were demonstrated by environmental and biological indicators. This work showed that the MOM-B system is a practical, simple, and sensitive environmental assessment tool that is easy to implement in estuarine and benthic bivalve aquaculture areas. It can be used for long-term continuous monitoring and as an early warning tool for benthic habitat quality.