Indicator Of Anthropogenic Influence Research Articles

A novel indicator of anthropogenic influence on the fluctuability and stability of phytoplankton community composition

Marine community composition is expected to be relatively stable in a natural environment over time but shift under increasing anthropogenic disturbances. In coastal waters, diatoms and dinoflagellates are two dominant phytoplankton functional groups. In this study, we developed an areal phytoplankton community composition index (APCI) that is based on the area of a scatter plot of dinoflagellate abundance (y-axis) vs diatom abundance (x-axis) using a time window of 1 year, 2 years or 3 years data. An APCI allows an ecological interpretation: it represents the fluctuability of a community composition within a time window and a temporal change between two neighbouring APCIs in a time series represents the stability of the composition. We used a 28-yr time series of monthly data on diatom and dinoflagellate abundance at four stations in Tolo Harbour and Channel (Tolo), Hong Kong to test the hypothesis that temporal changes in APCIs indicate environmental disturbances and to examine the applicability of APCI to indicate changes in nutrient conditions. We calculated the area (APCI) of a scatter plot of monthly data for 1-year, 2-year and 3-year windows, referred to as APCI-1y, −2y and -3y, respectively. The results show that, the fluctuability, is larger in APCI-3y than in APCI-1y, while the stability is stronger as temporal changes between neighbouring APCI-3y are smaller than between APCI-1ys. Temporal trends of APCIs are significantly correlated with those of dissolved inorganic nitrogen and phosphate concentration, which have declined after the implementation of a sewage diversion management plan in 1998. Hence, the APCI method is likely a robust indicator to assess a response of the phytoplankton community composition in a water body to environmental disturbances.

EVALUATION OF CHEMICAL INDICATORS OF ANTHROPOGENIC INFLUENCE IN THE LOWER DANUBE BASIN

The article explores the nature and trends of hydrochemical parameter connection and changes in the Lower Danube basin. The research examines nitrogen and phosphorus compounds, dissolved oxygen, and biochemical oxygen demand as indicators of anthropogenic influence and surface water quality alterations. The study was conducted between 2015 and 2023 at three sampling points: the Reni and Vilkovo water intakes on the Danube River and the Yalpuh Reservoir, which is connected to the Danube. The study employed mathematical statistics approaches. The research established changes in annual median values, investigated correlation links between chemical components by Spearman correlation, and implemented factor analysis by minimizing residuals. A spatiotemporal analysis of chemical components indicative of anthropogenic impact on the Lower Danube surface water revealed notable changes in the basin during 2019-2021. These changes were manifested as a sharp increase in ammonium concentrations and phosphate growth since 2020-2021, an abnormal decrease in dissolved oxygen concentration in 2019, a decrease in BOD within Yalpuh to the Danube BOD level, and a shift in trends from decreasing to increasing for nitrites. The water quality class also changed. Currently, the Danube River water is of the third quality class for nitrates, phosphates, and ammonium. In the Yalpuh Reservoir, it is of the 2nd class for nitrogen compounds and the 3rd class for phosphates. Two principal groups of chemical components are identified based on their underlying causes and sources, as revealed by correlation and factor analysis. A consistent relationship is observed between ammonium and phosphates across all monitoring sites, suggesting their role as pollutants entering surface waters via wastewater discharge and agricultural runoff and representing the main anthropogenic impact factor. The Danube River displays a specific relationship between nitrates and dissolved oxygen, reflecting the seasonal fluctuations in their concentrations and their underlying causes of changes, which stem from both anthropogenic and natural processes.

Towards understanding the characteristics of new particle formation in the Eastern Mediterranean

Abstract. To quantify the contribution of new particle formation (NPF) to ultrafine particle number and cloud condensation nuclei (CCN) budgets, one has to understand the mechanisms that govern NPF in different environments and its temporal extent. Here, we study NPF in Cyprus, an Eastern Mediterranean country located at the crossroads of three continents and affected by diverse air masses originating from continental, maritime, and desert-dust source areas. We performed 1-year continuous measurements of aerosol particles down to ∼ 1 nm in diameter for the first time in the Eastern Mediterranean and Middle East (EMME) region. These measurements were complemented with trace gas data, meteorological variables, and retroplume analysis. We show that NPF is a very frequent phenomenon at this site and has higher frequencies of occurrence during spring and autumn. NPF events were both of local and regional origin, and the local events occurred frequently during the month with the lowest NPF frequency. Some NPF events exhibited multiple onsets, while others exhibited apparent particle shrinkage in size. Additionally, NPF events were observed during the nighttime and during episodes of high desert-dust loadings. Particle formation rates and growth rates were comparable to those in urban environments, although our site is a rural one. Meteorological variables and trace gases played a role in explaining the intra-monthly variability of NPF events, but they did not explain why summer months had the least NPF frequency. Similarly, pre-existing aerosol loading did not explain the observed seasonality. The months with the least NPF frequency were associated with higher H2SO4 concentrations but lower NO2 concentrations, which is an indicator of anthropogenic influence. Air masses arriving from the Middle East were not observed during these months, which could suggest that precursor vapors important for nucleation and growth are transported to our site from the Middle East. Further comprehensive measurements of precursor vapors are required to prove this hypothesis.

Meltwater chemistry and characteristics of particulate matter deposited in snow as indicators of anthropogenic influences in an urban area.

A geochemical study of snow from the industrial town of Maribor (Slovenia) was performed. Concentrations of 61 elements in meltwater were determined, and a detailed semi-quantitative and qualitative analysis of individual PTE-bearing particles deposited in snow was performed with SEM/EDS. The physico-chemical characteristics of meltwater reflect the influence of winter road maintenance (high electrical conductivity and high Ca and Na concentrations close to the main roads) and industrial activities. Particulate matter deposited in snow consists mainly of carbonates and silicates, followed by carbon-rich particles and PTE-bearing particles. A higher abundance of PTE-bearing particles is typical for the industrial zones. The size, morphology and chemical composition of 4415 PTE-bearing particles were studied. They were organised into nine groups based on their characteristics. The majority were assigned to the group of Fe-oxides, which includes mostly angular particles of unidentified origin. Several groups of particles of anthropogenic origin were determined, mainly from industrial metal-processing activities. These particles include spherical Fe-oxides, Fe-alloys, other metal alloys and spherical Si-particles. Spherical Fe-oxides are typical for the Tezno industrial zone, while Fe-alloys, namely Fe-Cr (Cu, Mn, Ni) shavings and other metal alloys (Cu-Zn (Cl, Fe) shavings) are typical for the Melje industrial zone. The presence of naturally occurring mineral particles (e.g. zircon, ilmenite, monazite) reflects the influence of natural/geogenic sources on the composition of particulate matter deposited in snow. The presented study confirmed that snow is a very promising medium for the geochemical study of urban environments, especially for the identification of anthropogenic sources of particulate matter.

Terrestrial gastropods of the nature reserve Stary Zagaj and the town of skępe (dobrzyńskie Lakeland). The malacocoenosis structure as an indicator of anthropogenic influence in north-central Poland

1. Baur B. 1989. Growth and reproduction in the minute land snail Punctum pygmaeum (Draparnaud). Journal of Molluscan Studies 55: 383–387. https://doi.org/10.1093/mollus.... CrossRef Google Scholar

Spatiotemporal Assessment of Littoral Waterbirds for Establishing Ecological Indicators of Mediterranean Coastal Lagoons

Waterbirds are vital indicators of anthropogenic influence on the ecological status of Mediterranean coastal lagoons. Our study relates temporal waterbird data to key environmental gradients at catchment scale that have a structural or functional influence on littoral waterbird assemblages at different scales. During two full-year cycles and two additional wintering seasons, the nearshore waterbird assemblages of the Mar Menor coastal lagoon (Murcia Region, SE Spain) were monitored monthly. Several biological indicator variables were related to the anthropogenic environmental gradient in the catchment area. Results showed that there was a strong dependence of waterbird assemblages on the distance to shore, emphasizing the importance of the first 100-m band, in which many species relevant to conservation converge on food resources. Well-preserved shoreline tracts therefore had a clear positive effect on community richness and diversity values, and were correlated with the occurrence of some species. These results clearly support the need for effective protection and restoration measures of such littoral habitats. Specific responses to local disturbing processes were nested within habitat and landscape preferences, supporting the value of aquatic birds as integrative ecological signals in semi-enclosed coastal systems. Moreover, waterbird-based indicators responded positively to environmental improvements both qualitatively and quantitatively.

Anthropogenic influences on the physical state of submicron particulate matter over a tropical forest

Abstract. The occurrence of nonliquid and liquid physical states of submicron atmospheric particulate matter (PM) downwind of an urban region in central Amazonia was investigated. Measurements were conducted during two intensive operating periods (IOP1 and IOP2) that took place during the wet and dry seasons of the GoAmazon2014/5 campaign. Air masses representing variable influences of background conditions, urban pollution, and regional- and continental-scale biomass burning passed over the research site. As the air masses varied, particle rebound fraction, an indicator of physical state, was measured in real time at ground level using an impactor apparatus. Micrographs collected by transmission electron microscopy confirmed that liquid particles adhered, while nonliquid particles rebounded. Relative humidity (RH) was scanned to collect rebound curves. When the apparatus RH matched ambient RH, 95 % of the particles adhered as a campaign average. Secondary organic material, produced for the most part by the oxidation of volatile organic compounds emitted from the forest, produces liquid PM over this tropical forest. During periods of anthropogenic influence, by comparison, the rebound fraction dropped to as low as 60 % at 95 % RH. Analyses of the mass spectra of the atmospheric PM by positive-matrix factorization (PMF) and of concentrations of carbon monoxide, total particle number, and oxides of nitrogen were used to identify time periods affected by anthropogenic influences, including both urban pollution and biomass burning. The occurrence of nonliquid PM at high RH correlated with these indicators of anthropogenic influence. A linear model having as output the rebound fraction and as input the PMF factor loadings explained up to 70 % of the variance in the observed rebound fractions. Anthropogenic influences can contribute to the presence of nonliquid PM in the atmospheric particle population through the combined effects of molecular species that increase viscosity when internally mixed with background PM and increased concentrations of nonliquid anthropogenic particles in external mixtures of anthropogenic and biogenic PM.

The Influence of Urban Effluents on the Elemental C/N Ratio in a Tropical Coastal Area of Northeastern Brazil

ABSTRACT Travassos, R.K.; Flores Montes, M.J.; Costa, B.V. M., and Silva Junior, J.M., 2016. The influence of urban effluents on the elemental C/N ratio in a tropical coastal area of northeastern Brazil. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 168-172. Coconut Creek (Florida), ISSN 0749-0208. The present study was performed in a tropical and highly eutrophic estuarine system in the urban coastal area of Greater Recife, Pernambuco, northeastern Brazil. Organic carbon is introduced into these urban estuaries through domestic and industrial sewage waste. One indicator of anthropogenic influence is the concentration of organic matter, including the suspended elemental forms of carbon and total nitrogen and the C/N ratio. The distribution of the concentrations of both particulate organic carbon and total nitrogen (POC and TN, respectively) were...

Expansion of small terrestrial mammals and their parasites into the Barun Valley (Makalu Mt. Region, Nepal Himalaya) linked with changes in glaciation and human activities

The article is based on collection of small terrestrial mammals (Soriculus nigrescens, Episoriculus caudatus, Neodon sikimensis, Alticola stoliczkanus, Niviventer eha and Ochotona roylei) collected in the Barun Valley, east Nepal in the pre-monsoon period of 1973. Zoogeographic and ecological characteristics and altitudinal stratification of these species are analysed, depending both on abiotic (geomorphological and climatic) and biotic (vegetation, and human presence and activities) factors. All the captured mammals were examined for ecto- and endoparasities. Infestations of Trombiculid mites and Ixodid ticks were tightly linked to the local habitat where these ectoparasites must survive during their non-parasitic phase. Analysis of their occurrence completes the reconstruction of migration routes during the expansion of small mammals into the Barun Valley and the exacerbating influence of human activities (summer pasturing, mountaineering expeditions and trekking parties). An indicator of anthropogenic influence was the occurrence of synantropic flies. The potential medical importance of these findings is discussed. It is assumed a possible occurrence of arboviruses transmitted by ticks and also rickettsioses (transmitted by ticks and chigger mites). As far bacteriological infections, plague cannot be excluded.

Utility of soil linear alkylbenzenes to assess regional anthropogenic influences with special reference to atmospheric transport

Tracing regional anthropogenic influences is important for assessing the magnitude of human interferences with the environment. In the present study, the utility of soil linear alkylbenzenes (LABs) as indicators of anthropogenic influences was examined, with the emphasis on the role of atmospheric transport in dissipating LABs from input sources to remote areas. The Pearl River Delta, South China, which has experienced rapid economic growth and urbanization, was selected as the study region. The concentrations of LABs (mean: 8.6ng/g and median: 5.7ng/g, with an outlier of 2020ng/g excluded) suggested that sewage contamination throughout the entire study region was generally light. The spatial variation of sewage pollution was significantly positively correlated with population density and per capita gross domestic product, with hot spots concentrated in the central PRD. Atmospheric deposition was hypothesized as an important input route for soil LABs in forestry and drinking water source areas with little impact of irrigation or direct wastewater discharge. This proposition could explain the opposite spatial patterns of LAB concentrations and values of a biodegradation index (5-C12+5-C13)/(5-C11+5-C10), where i-Cn defines a specific LAB congener with i and n indicating the position of the phenyl group and the number of carbon atoms on the alkyl chain, respectively. These findings somewhat validated LABs as tracers of regional anthropogenically derived contamination, with atmospheric transport of LABs as a viable dissipating mechanism.

Identification of Neolithic to Modern erosion–sedimentation phases using geochemical approach in a loess covered sub-catchment of South Moravia, Czech Republic

A colluvial soil with a 380cm deep humus enriched horizon was studied in a loess region of South Moravia, Czech Republic, which is characterized by a strong soil material re-deposition. Distribution of soil properties within the colluvial soil profile was used for distinguishing the different sedimentation phases and understanding colluvial soil formation. The colluvial profile is stratified into different horizons distinguishable by a specific distribution of basic soil properties (soil organic carbon content, carbonate content or soil reaction) in the profile. Low organic carbon content (0.6–0.8%) and increased carbonate content (up to 8%) in the upper 260cm indicates a rapid change of the soil cover and significant admixture of loess parent material in the sediment. An abrupt increase of organic carbon content (2%) and no carbonates between 300 and 380cm, is evidence of a buried Chernozem at this depth. Antropogenically induced substances, such as pesticide residues or increased nutrient content, connected to agricultural practices, enables the detection of sedimentation periods. The peak DDT content (up to 0.04mg/kg) at the depth of 50–150cm clearly delineates the material sedimented in the 1950s–1970s and material sedimented in earlier or later stages. The same trend can be traced in phosphorus and potassium content, given by intensive use of fertilizers at a given time period. The potential use of lead and cadmium as another indicator of anthropogenic influence at some stage of soil sedimentation was not proven due to their low concentration in the colluvial profile. Three phases of soil erosion and sedimentation were distinguished, each reflecting different land use and intensity of agriculture. The highest amount of soil material (2m) deposited in the colluvial profile can be attributed to the last and shortest erosional phase corresponding to intensive agriculture and massive land consolidation in the last 70years.

Fe, Mn, P and S Speciation in Sediments from the Capivara Hydroelectric Dam Lake (Brazil) as an Indicator of Anthropogenic Influences

AbstractThe conservation of large water resources is essential for the preservation of human life. The quantification and, more importantly, the speciation of chemical substances that indicate the presence of anthropogenic contamination in water resources are of great importance. This paper presents the results of analysis for the determination of organic, inorganic and total phosphorus, pseudo‐sulfur, and iron and manganese, in five fractions, in water sediments collected from the Capivara Hydroelectric Power Plant, Brazil. A study on the seasonal variation of these parameters was conducted, with data having been collected in the winter and in the summer, at two sites along the dam, 5 km apart, close to the city of Primeiro de Maio. Phosphorous was found in sediments and adjacent soil in the organic form (OP), and was used as an indicator of anthropogenic influence on the reservoir banks. Speciation of potentially toxic Mn showed that it is present in the exchangeable fraction of the 0–5 cm depth layer (sediment/water interface), making its transfer to the water column possible. Results from this study showed that domestic and industrial effluent treatment measures are needed for the preservation of the quality of aquatic environments.

Екологічні особливості та біоіндикаційне значення черепашкових амеб (Testacea, Rhizopoda) у природних і антропогенно трансформованих біогеоценозах

Проаналізовано фізіологічні та екологічні особливості черепашкових амеб Testacea, Rhizopoda. Підкреслено, що тестації можуть виступати біоіндикаторами різноманітних ґрунтових умов у природних біогеоценозах. Наведено дані з використання представників надкласу Rhizopoda як показників антропогенного впливу на ґрунти.

Microorganisms of Lake Baikal and Lake Nyasa as Indicators of Anthropogenic Influence: Prospects for Use in Biotechnology

Restriction endonucleases (RENs) were detected in 650 microbial strains isolated from water columns and bottom sediments of deep rift lakes, Baikal (Russia) and Nyasa (Southeastern Africa). They enzymes included unique (Fan I, Aca I, and Sse 91) and very rare (Bsi I, and Cci N I) species not typical of aquatic ecosystems. Water columns, deep cores, and bottom sediments of pure areas of the lakes contained no microorganisms with new RENs. Thus, inshore areas of Lake Baikal exposed to anthropogenic influence may contain mutant bacterial strains expressing RENs that have not been described previously.

Prevalence of Gross Pathological Abnormalities in Estuarine Fishes

Abstract Gross external pathological abnormalities are frequently used as indicators of anthropogenic influence in estuarine and marine waters, but little baseline information is available to identify what constitutes normal prevalences (percentages of animals affected). To establish this baseline, trawl samples were collected from 120 randomly located estuarine sites in the Virginian biogeographic province (mid-Atlantic) in 1990 and from 220 randomly located sites in the Louisianian biogeographic province (Gulf Coast) in 1991 and 1992. Sediment contaminant concentrations were measured at each site. In all, 24,291 fish representing 143 species were examined for gross pathological abnormalities, and background prevalences were estimated to be 0.5% in midAtlantic and 0.7% in Gulf Coast estuaries. Fifteen types of gross abnormalities were noted. Skin lesions were the most prevalent abnormalities in both provinces, followed by ocular abnormalities (e.g., exophthalmia, keratitis) in the Virginian Province and ...