Anthropogenic Activities Research Articles

Decadal trends of black carbon and heavy metal accumulation in a lake sediment core from central China: A historical perspective

Black carbon (BC) and heavy metal are vital indicators of historical human activities. This study investigates the historical pollution trends of BC, char, soot, and heavy metals in lake sediments from Yinjia Lake (YJL). BC, char, and soot concentrations exhibit similar historical trends, with average values of 1.59, 1.27, and 0.32 mg/g, respectively. Char, constituting 67.25–85.85 % of BC, indicates a dominant fraction in the lake. A notable increase in BC, char, and soot was observed post-1955, peaking in 2005, followed by a decline, reflecting local economic development and anthropogenic activities. Heavy metals, including Cu, Cd, Zn, Pb, Cr, Co, Ni, and Mn, also displayed a significant increase post-1950, with Cd showing an exceptionally high concentration. The average deposition fluxes of BC, char, and soot were consistent with their concentrations, peaking in 2005. The correlations between BC, char, soot, and heavy metals suggest BC’s role as a metal carrier, influenced by industrial and anthropogenic emissions. The char/soot ratio analysis indicates predominant biomass burning pre-1950 and increased fossil fuel combustion post-1950, with regional variations observed. The study highlights the impact of industrialization, urbanization, and policy changes on pollution trends in YJL.

Prediction of environmental suitability for Haematoxylum campechianum: a proposal to promote reforestation in Mexico

Models of potential distribution and ecological niche allow to estimate priority areas for the management of species of interest, as well as to identify variables related to environmental suitability and predict the behavior of species in the face of anthropogenic disturbances. Logwood (Haematoxylum campechianum) is a species that we consider a natural heritage in southeastern Mexico because of its ecological role and the current and historical use of its wood. This species is present in different vegetation types and even dominates in some ecosystems called "tintales", which have been exploited for dye extraction in past centuries. This, combined with changes in land use for livestock, agriculture, and other anthropogenic activities, has affected the Logwood´s distribution and connectivity of its populations. We modeled the potential distribution of H. campechianum and evaluated the feasibility of reforestation with this species in southeastern Mexico. For this purpose, we included 638 occurrence points and used the MaxEnt algorithm for modeling, analyzing different parameters. We used the potential distribution model, accessibility to the areas and water availability to calculate a feasibility index for reforestation. The environmental suitability for the species is more present in southeastern Mexico, conditioned by the aridity index, the maximum temperature of the coldest month and the warmest month. The greatest percentage of areas with high feasibility indexes for reforestation are found in Campeche, apparently a key state for the conservation and management of the species. This study can be the starting point for implementing reforestation programs with H. campechianum and can be used as an example to apply to other species with patrimonial value.

Coastal vertical land motion across Southeast Asia derived from combining tide gauge and satellite altimetry observations

Vertical land motion (VLM) is complex in Southeast Asia because this region is subject to a range of natural processes (e.g., earthquakes) and anthropogenic activities (e.g., groundwater withdrawal) that can change land heights. To aid in coastal management, long-term observations of VLM are as crucial as observations for climate-induced sea surface height changes; however, such long-term observations are sparse for Southeast Asian coasts. To fill this observational gap, here we derive monthly VLM time series from 1993 to 2020 at 50 coastal sites across Southeast Asia by combining tide-gauge records and newly generated satellite altimetry observations. These altimetry observations are reproduced sea-level products using new altimetry standards and more accurate geophysical corrections. Our 27-year-long VLM dataset shows high spatial variability and non-linear temporal changes in VLM across Southeast Asia. We identify several major sources that dominate the regional land-height changes, which include large subsidence due to groundwater extraction in Manila and Bangkok, land uplift in Indonesia and subsidence in Thailand from postseismic deformation resulting from the sequence of large Sumatran earthquakes since 2004, and land subsidence as a result of sediment compaction in Malaysia. Those signals are quantitatively or qualitatively consistent with observations from other sources. This VLM dataset can be used to advance our understanding of the physical mechanisms behind land-height changes and to improve sea level projections in the region.

The gut microbiome and resistome of yellow perch (Perca flavescens) living in Minnesota lakes under varying anthropogenic pressure

Anthropogenic activities can significantly impact wildlife in natural water bodies, affecting not only the host's physiology but also its microbiome. This study aimed to analyze the gut microbiome and antimicrobial resistance gene profile (i.e., the resistome) of yellow perch living in lakes subjected to different levels of anthropogenic pressure: wastewater effluent-impacted lakes and undeveloped lakes. Total DNA and RNA from gut content samples were extracted and sequenced for analysis. Results indicate that the gut resistome and microbiome of yellow perch differ between lakes, perhaps due to varying anthropogenic pressure. The resistome was predominated by macrolide resistance genes, particularly the MLS23S group, making up 53 % of resistome sequences from effluent-impacted lakes and 73 % from undeveloped lakes. The colistin resistance gene group (mcr) was detected in numerous samples, including variants associated with Aeromonas and the family Enterobacteriaceae. The gut microbiome across all samples was dominated by the phyla Proteobacteria, Firmicutes, and Actinobacteria, with the opportunistic pathogens Plesiomonas shigelloides and Aeromonas veronii more abundant in effluent-impacted lakes. Metagenomic analysis of wild fish samples offers valuable insights into the effects of anthropogenic pressures on microbial communities, including antimicrobial resistance genes, in water bodies.

The interplay between prehistoric vegetation, climatic fluctuations and anthropogenic activities in Central China

The interaction between climate, hydrological environment, and human activities in prehistoric times has consistently attracted significant interest. However, the process and mechanism of this interaction remain unclear due to a lack of detailed materials that provide information on both human activity and environmental evolution. Here we present a comprehensive dataset of optically stimulated luminescence (OSL) dating and pollen analysis derived from lacustrine facies deposits in the vicinity of the Dongzhao Site in Central China, which is a key region for the origin and development of Chinese civilization. These data have revealed the existence of multiple cycles of environment-human interaction during prehistoric periods. The gradual improvement in the climate and minor fluctuations facilitated the settlement of prehistoric populations in the region, fostering uninterrupted cultural development for millennia since the early Holocene. The increase in population and intensification of human activities significantly affected regional vegetation, resulting in a decrease in the number of trees around 4.0 ka BP. Environmental changes influenced the prehistoric architectural style, resulting in a decrease in houses with “wood bone and mud walls” that were prevalent during the Yangshao periods (7.0–5.0 ka BP) due to a lack of trees. Our research once again highlights the perpetual cycle of interdependence and interaction between natural environments and human activities.

Hydrochemical characteristics of groundwater and their controlling mechanisms in irrigation and non-irrigation areas - a comparative study in the Guanzhong Plain of China

Gaining insight into groundwater chemistry and its evolution in irrigation areas is essential for optimizing irrigation strategies. This study explores the origins and influencing variables of groundwater chemistry across both irrigated and non-irrigated areas of the Guanzhong Plain, aiming to elucidate how irrigation practices impact hydrochemical changes. Hydrochemical data, isotopic data, multivariate statistical techniques and hydrochemical methods were used in this study. The findings underscored that groundwater in non-irrigation areas had low total dissolved solids, with 90% of the groundwater samples exhibiting the HCO3-Ca•Mg type. In comparison, groundwater from irrigation areas showed elevated total dissolved solids levels and diverse hydrochemical types, including HCO3-Ca•Mg, HCO3-Na, and SO4•Cl-Ca•Mg types. These categories collectively represented 88% of the water samples from irrigation areas. Isotopic and hydrochemical analyses revealed that groundwater in irrigation areas experienced more intense evaporation and cation exchange. Furthermore, anthropogenic activities like sewage and manure had a more pronounced effect on groundwater chemistry in irrigation areas. Groundwater suitability for irrigation deteriorated from the western irrigation area to the eastern irrigation area. This research offers a robust scientific foundation for the careful management and conservation of groundwater resources in the region.

Fabrication of chitosan coated bentonite clay multifunctional nanosorbents from waste biomass for the effective elimination of hazardous pollutants from waterbodies: A fixed bed biosorption, mechanism, and mathematical model study

The anthropogenic activity and hasty fluctuating technologies have been responsible for the generation of massive effluent which is so hazardous due to the loading of several toxicants. While most industries usually discharge it directly into the environment resulting in harsh damage to the ecology/public security. Therefore, it is critical to treat with a sustainable/cost-effective technique. Here, a new route of fabrication of chitosan-coated activated natural bentonite clay (CCANBC) bionanocomposites/bionanosorbents from waste biomass has been developed. Their potential application for the simultaneous removal of Ni2+ and Eosin Y from wastewater were investigated. The effective parameters like concentration (10–30 ppm), flow rate (2–4 mL/min), and bed height (0.5–1.5 cm) were inspected. The bionanosorbents were characterized by FTIR-ATR, XRD, FESEM, TGA, and BET analysis. Additionally, the effluents were explored by AAS and UV–vis-NIR spectroscopy. According to the findings it has been stated that the CCANBC bionanosorbents possessed significant dynamic edges, greater crystallinity (94.27 %), and higher thermal stability. They have exhibited a remarkable 2D honeycomb-like mesoporous microstructure with substantial specific surface area (19.29 m2/g). These outstanding features could be responsible for the dramatic adsorption enactment around 186.42 and 238.37 mg/g for Ni2+ and Eosin Y. The obtained data were evaluated by several mathematical models for better understanding the experimental BTC curve, reaction mechanism, and adsorption isotherm.

A spatio-temporal assessment of seawater quality in Miri-Sibuti Coral Reef: Evaluating for metal pollution, sources and dynamics

Coral environments are sensitive to seawater quality, and their sustenance depends on understanding the dynamics of geochemical variables, especially in trace levels. Miri-Sibuti Coral Reef National Park (MSCRNP) is a unique marine reserve in the state of Sarawak, NW Borneo, Malaysia, which attracts tourists worldwide. In this study, seawater samples were collected from MSCRNP in three different diving sites (Eve’s Garden (EG), Anemone Garden (AG) and North Siwa (NS)) at different depths for three seasons (pre-southwest monsoon (PRSWM), post-southwest monsoon (POSWM) and northeast monsoon (NEM). Insitu parameters (temperature, pH, salinity and turbidity) were measured in the field. The concentration of trace metals was determined in the water column (sea surface layer, middle layer and bottom water) using standard procedure. Statistics and pollution indices were used to identify the possible sources of metals and the pollution status of the seawater. From the analytical results, the vertical distribution of trace metal concentrations with respect to the locations and seasons was identified. pH ranging from 7.8 to 8.4 with a depth-wise increasing trend in NS during NEM. Similarly, a decreasing trend of turbidity was observed in AG and EG in all the seasons with respect to depth. A higher concentration of trace metals was observed during NEM, particularly at EG and NS. Fe, Ni and Pb are the dominant metals in all the seasons. Fe concentration varies from 789 to 1,478µg/L, averaging 1,112µg/L irrespective of seasons and locations. The suspended solids/sediments discharged by the river runoff were the main contributor to the distribution of metals. The release of metals from the suspended particles through desorption at the surface layers and the exchange of metals between water-sediment interface at the bottom water were observed. In addition, coastal development and other anthropogenic activities in this region were also contributed to the metal pollution.

Method Development and Comprehensive Study of Matrix Effects for the Determination of Trace Organic Contaminants in Lake Sediments

The presence of trace organic contaminants (TrOCs), such as pharmaceuticals, personal care products, additives, and polar pesticides in sediments of rivers and lakes highly impacted by anthropogenic activities makes sediments a secondary source of contamination for aquatic ecosystems. Considering this, a method for analyzing 44 TrOCs of diverse nature (including five transformation products, 13 pharmaceuticals, five personal care products, 14 pesticides, and seven additives) was developed and validated. It is based on extraction by pressurized liquid extraction (PLE), followed by purification and pre-concentration by solid phase extraction (SPE) and quantification by liquid chromatography coupled to a triple quadrupole mass spectrometer (LC-QqQMS). The method was optimized according to dispersant type, temperature, and extraction solvent. The influence of organic matter in sediments on quantitative analysis was also investigated in detail. Matrix effects were highly and significantly correlated (r=-0.9146, p < 0.0001) with retention time. Using internal standards showed the best results for effectively correcting matrix effects without affecting method sensitivity. The method was then validated according to key figures of merit: linearity (R2 > 0.990), extraction recoveries (> 60% for 34 compounds), trueness (bias % < 15%), precision (relative standard deviation < 20%) and matrix effects (between -13.3% and 17.8%). This method can be applied for routine analysis of TrOCs in different sediment matrices. The method was applied to ten lake sediment samples collected in Québec, Canada. Results demonstrated the presence of 17 compounds in at least one lake at concentrations between 0.07 to 1531 ng g-1. The reported concentrations provide a first picture of the occurrence of chemical stressors in sediments of small lake highly anthropized ecosystems in Eastern Canada.

The human dimensions of harmful algal blooms: An evolving research agenda

Harmful algal blooms (HABs) are a global phenomenon occurring in a range of aquatic environments, with the potential to have diverse environmental, social and economic impacts. There is growing interest in the human dimensions of HABs particularly as a result of the increased occurrence of HABs linked to anthropogenic activities. However, to date this has focused more on the economic and health implications of HABs events rather than broader human dimensions. This paper presents a series of research priorities that could strengthen social science research on HABs, highlighting topics related to public awareness and attitudes, community science, governance and co-development of solutions, links to the blue economy agenda, impacts on marine culture and heritage, and impacts on health and wellbeing. Finally, the paper presents a series of recommendations developing a transdisciplinary research agenda in order for the ongoing challenges of HABs to be addressed.

Evaluating the role of recalcitrant dissolved organic matter in bacterial community dynamics in urbanized freshwater ecosystems

Dissolved organic matter (DOM) and recalcitrant dissolved organic matter (RDOM) play distinct roles in shaping microbial communities. However, characterizing these roles is difficult, especially in ecosystems subjected to varying degrees of anthropogenic influence. This study investigated the molecular compositions and ecological impacts of DOM and RDOM in the Fen River, Shanxi Taiyuan, comparing pristine upstream regions with highly urbanized downstream areas. Using 16S rRNA gene sequencing and LC-MS-based metabolomics, we observed significant shifts in microbial community composition, diversity, and metabolic functions. Upstream communities, characterized by higher diversity, were dominated by Bacteroidota, Proteobacteria, and Cyanobacteria, while downstream communities, influenced by pollution, exhibited increased expression of genes related to amino acid metabolism. Fluorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) revealed that upstream DOM contained higher proportions of complex, high molecular weight compounds, including significant proportions of carboxyl-rich alicyclic molecules (CRAM) and island of stability (IOS) compounds, which play key roles in long-term carbon storage and microbial carbon sequestration. In contrast, downstream DOM was characterized as having lower aromaticity and more saturated compounds, with reduced proportions of CRAM and IOS, reflecting the impact of anthropogenic activities. These findings underscored the critical roles of CRAM and IOS in regulating DOM stability and microbial communities, further highlighting the need for targeted pollution control strategies to preserve ecosystem function in urbanized water bodies.

Heavy metal concentration in marine water: An assessment of ONGC’s blocks in Mumbai High Region, Arabian Sea

Heavy metal pollution, in the aquatic ecosystem, has become an area of concern garnering increasing attention since the past few decades. Some metals like manganese (Mn), copper (Cu), iron (Fe) and zinc (Zn) are biologically important for marine life. Other non-essential metals like lead (Pb), cadmium (Cd), and Arsenic (As) become toxic at higher concentrations. These metals are introduced into the marine ecosystem mainly due to anthropogenic activities. Hence, monitoring the heavy metal concentrations in these marine water over a period of time is of great help in checking the pollution level and identifying the trend, which in turn will be instrumental in formulating sustainable practices. The paper mainly focuses on the study of the concentration of lead (Pb), cadmium (Cd), and Arsenic (As) in sea water around the operational areas of ONGC in Waestern offshore. The distribution of heavy metals in the seawater of ONGC’s exploratory blocks in Mumbai High Region, Arabian Sea was studied. Fifty four sea water samples were collected as per OSPAR Commission guidelines from each blocks (Block A, Block B, Block C, Block D and Block E) of Mumbai High Region, Arabian Sea and processed samples were analyzed by ICP-MS for Pb, As, and Cd. Comparison of average results in studied 5 blocks with various seawater quality guidelines is discussed to assess the present level of contamination. The study reveals that seawater in study area is not contaminated with respect to perceived heavy metals. Generated data will assist in future for proactive measures to minimize the impact of anthropogenic sources.

Habitat Assessment of Bocachico (Prochilodus magdalenae) in Ciénaga de Betancí, Colombia, Using a Habitat Suitability Index Model

This study evaluates the habitat of the Bocachico fish (Prochilodus magdalenae) in the Ciénaga de Betancí, Colombia, using a habitat suitability index (HSI) model. Wetlands like the Ciénaga de Betancí are under significant pressure from anthropogenic activities, affecting biodiversity and ecosystem health. The Bocachico, a species of immense cultural and economic importance, faces habitat degradation and fragmentation. Using hydrodynamic and water quality data, a numerical model (EFDC+ Explorer 11.5), and field data collected from multiple sampling campaigns, we assessed habitat suitability based on five key parameters: water temperature, dissolved oxygen, ammonia nitrogen, velocity, and depth. The model results indicated that environmental conditions in the wetland remained relatively stable during the dry season, with an average HSI score of 0.67, where 9% of the wetland area displayed acceptable conditions, and the remaining 91% displayed medium conditions. The wet season, on the other hand, had an average HSI score of 0.64, with 7.2% of the area in the acceptable suitability range, and the remaining 92.8% in the medium category. Variations in HSI were primarily driven by ammonia nitrogen levels, water velocity, and depth. Despite limited fluctuations in the HSI, areas of low suitability were identified, particularly in regions impacted by human activities. These findings have practical implications for conservation strategies, providing valuable insights for the sustainable management and conservation of the Ciénaga de Betancí, informing strategies for improving habitat conditions for the Bocachico, and supporting wetland restoration efforts.

Residents’ willingness to pay for sustainable solid waste management services: a case of Glenview suburb, Harare, Zimbabwe

AbstractSolid waste generation is an inevitable outcome of anthropogenic activities, which is an issue of concern in Zimbabwe. Among other challenges, inadequate finance is a key challenge to reach sustainable waste management. This study focuses on residents’ willingness to pay for improved solid waste management services. Analytical case study research design, employing quantitative and qualitative data collection, analysis and presentation was adopted. Data was collected using questionnaires, interviews, observations while analysis was done using SPSS and content analysis. Results indicated that most respondents were house owners (53.92%) and 46.08% were tenants. Solid waste generated consists of hazardous and non-hazardous waste. Solid waste collected by the city council (57.84%), private collectors (36.27%) while remaining is collected by other individuals and scavengers. Interviews and questionnaires outcomes denote that solid waste was collected once a week (43.14%), twice a week (3.92%) and rarely collected (38.24%). Solid waste is disposed through open dumping, burning, pits and landfilling, although most of the disposal strategies pose environmental health problems. Solid waste mismanagement is attributed to lack of awareness, weak legal framework and shortage of resources, specifically finance. Questionnaire respondents (66.67%) argued that proper solid waste management is important and needs to be improved. Participants (65.69%) revealed that they were willing to pay for improved solid waste management, however, 34.31% were unwilling. Willingness to pay for improved solid waste management was determined by educational level and house ownership status. Improving residents’ willingness to pay for proper solid waste management requires an integrated approach and increasing residents' awareness.

The Bioaccumulation of Potentially Toxic Elements in the Organs of Phragmites australis and Their Application as Indicators of Pollution (Bug River, Poland)

The bioaccumulation of potentially toxic elements (PTEs) in aquatic plants is critical in assessing the quality of aquatic environments and the risks associated with anthropogenic activities. This research involved using Phragmites australis as a bioindicator in a comprehensive assessment of the spatial variation in pollution within the Bug River catchment, employing advanced statistical methods to identify pollution sources. The study aimed to investigate the bioaccumulation of PTEs in different parts of the P. australis plant and to evaluate their suitability as bioindicators of contamination. Plant samples were collected from 32 locations in the Bug River catchment, and the concentrations of metals such as Cd, Pb, Cr, Ni, Zn, Cu, Fe, and Mn were determined by atomic absorption spectrometry. The results indicated that PTE accumulation was highest in the roots, underscoring their crucial role in monitoring metal concentrations. Metal concentrations differed based on land use within the catchment area, with the highest levels observed in urbanized regions, highlighting the significant impact of human activities like wastewater discharge and transport emissions. The highest concentrations were observed for Fe, Mn, and Zn, while Cd concentrations were notably elevated in agricultural areas. The analyses confirmed that P. australis serves as an effective bioindicator of heavy metal contamination and can be employed in long-term biomonitoring programs.

Geochemical assessments and human health risk evaluations of selected farm soils within the Abuja metropolis, North-central, Nigeria

Toxin accumulations in agricultural soils decreases the crop quality and productivity, and threatens the safety of foods, which could cause adverse human health effects. This study assessed the risks associated with potential toxins in the agricultural soils obtained from Lugbe and Jikwoyi in Abuja, Nigeria. An analytical technique for absorption spectrophotometry was adopted, and human health risks were evaluated. Twenty soil samples were collected from two farmlands, and two control samples were taken on unpolluted sites at depths 5-20 cm from the surface at the average suspension of plant roots where the soil holds most plant nutrients and water at a space interval of 5 m. The soils generally had low mean concentrations of Ca, Cu, Zn, Mn, Fe, and Co and moderately high mean concentrations of F, Ni, Pb, Cr, and Mo. The pattern of the pollutants reflected that the pollutants were majorly from anthropogenic activities, such as long-term fertilizer applications and other agrochemicals. The contamination indices revealed reassuringly low to moderate pollution risks to humans. The overall pollution loads suggested that the samples were largely unpolluted. The non-carcinogenic and carcinogenic health risks were within the safety limits for inhalation, dermal, and ingestion, which pose no significant risk to children and adults living in the vicinities of the farmlands. The cancer risks for inhalation were higher than dermal and ingestion, with Cr showing the highest values. The samples were slightly contaminated with potentially toxic metals, which could lead to increased phyto-accumulations, soil pollution, and groundwater contamination.

Seasonal Variation of Physicochemical Properties in the Lower River Benue, Nigeria

The study investigates the impact of seasonal changes on water quality in the River Benue, Nigeria. Conducted over eighteen months from January 2020 to June 2021, the research focuses on three locations: Ibi, Lau, and Mayo-Ranewo. Key physicochemical parameters such as temperature, pH, turbidity, conductivity, Biochemical Oxygen Demand (BOD), hardness, dissolved oxygen (DO), fluoride, and nitrate were measured to assess water quality. The findings reveal significant seasonal variations in these parameters, influenced by rainfall patterns, land use, and anthropogenic activities. Temperature ranged from 25.56°C to 30.70°C, remaining within acceptable limits for tropical waters, supporting stable biological processes. However, turbidity levels exceeded recommended values, indicating the presence of suspended solids that could impair water quality and harm aquatic life. Total dissolved solids (TDS) and conductivity showed potential contamination risks, likely due to agricultural runoff and urban discharges. Dissolved oxygen (DO) levels were generally adequate, especially during the wet season, enhancing oxygen content through increased photosynthetic activity and water inflows. However, BOD spiked with rainfall, signalling organic pollution and potential eutrophication risks. Seasonal shifts in pH and water hardness reflected changes in runoff and photosynthesis, with values largely within acceptable ranges for aquatic life. Fluoride and nitrate concentrations increased in the wet season, primarily due to agricultural runoff, highlighting the influence of land-based activities on water quality.

Gene horizontal transfers and functional diversity negatively correlated with bacterial taxonomic diversity along a nitrogen gradient.

Horizontal gene transfer (HGT) mediated diversification is a critical force driving evolutionary and ecological processes. However, how HGT might relate to anthropogenic activity such as nitrogen addition, and its subsequent effect on functional diversity and cooccurrence networks remain unknown. Here we approach this knowledge gap by blending bacterial 16S rRNA gene amplicon and shotgun metagenomes from a platform of cessation of nitrogen additions and continuous nitrogen additions. We found that bacterial HGT events, functional genes, and virus diversities increased whereas bacterial taxonomic diversity decreased by nitrogen additions, resulting in a counterintuitive strong negative association between bacterial taxonomic and functional diversities. Nitrogen additions, especially the ceased one, complexified the cooccurrence network by increasing the contribution of vitamin B12 auxotrophic Acidobacteria, indicating cross-feeding. These findings advance our perceptions of the causes and consequences of the diversification process in community ecology.

Genotoxic impact of agricultural insecticides as contaminants of river Teesta on the resident fish Pethia Conchonius.

Fish, being highly sensitive to changes in the physico-chemical parameters of water, are good indicators of contamination. Teesta, a prominent northern West Bengal River system, is increasingly contaminated due to anthropogenic activities. This study aims to determine agricultural pesticide contamination and its genotoxic impact on the resident fish, Pethia conchonius, as an experimental organism. Sample water analysis from three riverine sites I, II & III, showed the presence of the insecticides imidacloprid (IMI), chlorpyrifos (CPF), bifenethrin (BF), cypermethrin (CP), difenthiuron, acetamiprid (AC) in the sites II and III only with adjoining agricultural lands. Comet assay revealed a significantly lower % Head DNA (~ 1.2 times), higher %Tail DNA (~ 16 times), and %Tail length (~ 3.1 times) in the gills of Pethia conchonius from sites II and III. About 4 and 10 times increase of micronuclei and other nuclear abnormalities were also noted in the erythrocytes of the fish from sites II and III than I, which was not contaminated. The antioxidant enzymes SOD, CAT, and GST activity and MDA levels were significantly higher (p < 0.05) in the liver samples from sites II and III, while AChE activity was significantly decreased (p < 0.001) in the brain tissues. Moreover, the sod, cat, and gpx expression in the hepatic cells were significantly upregulated compared to the β actin mRNA indicating increased oxidative stress. Increased genomic damage, antioxidant enzyme activity, higher MDA levels, decreased AChE activity in the brain, and the upregulation of hepatic genes strongly suggested the genotoxic effects of the detected insecticides in combination with other contaminants.

Planning eco-sensitive zones for promoting tree diversity and ecosystem services in urban academic landscapes: a case study from the North-western Indo-Gangetic plain

ABSTRACT Urban academic greenspaces provide a protective environment for the conservation of plants and animals and ecological health benefits to human beings. Several anthropogenic activities and landscape practices lead to patches of natural and built-up areas; therefore, a better understanding of campus tree diversity and ecosystem services among natural and built-up areas may help in biodiversity management. Considering this, we assessed how landscape heterogenicity (i.e. the proportion of natural and built-up/paved surface area) and planning principles influence tree density and diversity patterns in three zones (buffer zone: natural/remnant woodland; transition zone: mixed open grassland and woody plantation; core zone: paved/built-up, grassland, and scattered woody plantation) in the Indian Institute of Science Education and Research (IISER) Mohali campus (Punjab) India. We found a total of 1,993 trees belonging to sixty-eight species, mostly native flora. We found that landscape planning principles significantly influenced tree diversity patterns, with the highest tree diversity in the B3 buffer zone (H: 2.9, PIE: 0.9), which integrated elements of the original landscape and new plantations to optimise ecological value and the lowest diversity in the B2 buffer zone (i.e. H: 0.4; PIE: 0.2) with a monoculture plantation of exotic agroforestry species. We also observed that tree density was negatively influenced by impervious surface area (r = -0.68, p < 0.05) in the core zones and by the plantation of exotic species in the natural areas. The campus diversity supports birds of different feeding guilds (insectivore: 41%, omnivore: 25%, carnivore: 25%, frugivore/nectarivore: 13%, graminivore: 4%, and piscivore: 2%). Additionally, academic buildings planned with high canopy cover and density (45% and 95 ha−1) had reduced the wall temperatures of academic buildings from 12°C to 6°C compared to neighbouring buildings without tree cover. This highlighted the importance of maintaining tree diversity in urban academic institutions to promote urban sustainability.