The impact of anthropogenic activities on nutrient dynamics in the tropical Wenchanghe and Wenjiaohe Estuary and Lagoon system in East Hainan, China

The concept of combined scientific information and objectivism, and carefulness prevention, are crucially required for the design of Lake Kinneret ecological services management. The integration of ecological structure and management is an assets of permanent value. Three test cases of that concept as incorporated within the usage policy of Lake Kinneret are presented and criticized. It is discussed through an insight into three cases of decision making process: 1) Nutrient dynamics (N, P and N/P mass ration) and the first record of N2-fixer- Cyanobacterium bloom; 2) The impact of natural and anthropogenic activities on the decline and recovery of Tilapias fish population; and 3) The consequences of water level decline on their quality. The objective of the paper is to improve both, safety and sevices of the ecosystem.

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Chemical Composition and Metal Speciation in Porewaters from the Upper Qu’Appelle River Basin, Saskatchewan

Water Quality Research Journal ◽

10.2166/wqrj.1993.005 ◽

1993 ◽

Vol 28 (1) ◽

pp. 83-110 ◽

Cited By ~ 1

Author(s):

Richard E. Farrell ◽

Jae E. Yang ◽

P. Ming Huang ◽

Wen K. Liaw

Keyword(s):

Amino Acids ◽

Trace Metal ◽

River Basin ◽

Drainage Basin ◽

Metal Speciation ◽

Anthropogenic Activities ◽

High Concentration ◽

Metal Concentrations ◽

Carbonate Equilibria ◽

The Impact

Abstract Porewater samples from the upper Qu’Appelle River basin in Saskatchewan, Canada, were analyzed to obtain metal, inorganic ligand and amino add profiles. These data were used to compute the aqueous speciation of the metals in each porewater using the computer program GEOCHEM-PC. The porewaters were classified as slightly to moderately saline. Metal concentrations reflected both the geology of the drainage basin and the impact of anthropogenic activities. Whereas K and Na were present almost entirely as the free aquo ions, carbonate equilibria dominated the speciation of Ca. Mg and Mn (the predominant metal ligand species were of the type MCO3 (s). MCO30. and MHCO3+). Trace metal concentrations were generally within the ranges reported for non-polluted freshwater systems. Whereas the speciation of the trace metals Cr(III) and Co(II) was dominated by carbonate equilibria, Hg(II)-, Zn(II)- and Fe(II)-speciation was dominated by hydroxy-metal complexes of the type M(OH)+ and M(OH)2°. The speciation of Fe(III) was dominated by Fe(OH)3 (s). In porewaters with high chloride concentrations (> 2 mM), however, significant amounts of Hg(II) were bound as HgCl20 and HgClOH0. The aqueous speciation of Al was dominated by Al(OH)4− and Al2Si2O4(OH)6 (s). Total concentrations of dissolved free amino acids varied from 15.21 to 25.17 umole L−1. The most important metal scavenging amino acids were histidine (due to high stability constants for the metal-histidine complexes) and tryptophan (due to its relatively high concentration in the porewaters. i.e., 5.96 to 7.73 umole L−1). Secondary concentrations of various trace metal-amino add complexes were computed for all the porewaters, but metal-amino acid complexes dominated the speciation of Cu(II) in all the porewaters and Ni(II) in two of the porewaters.

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Ground-Based MAX-DOAS Observations of Tropospheric NO2 and HCHO During COVID-19 Lockdown and Spring Festival Over Shanghai, China

Remote Sensing ◽

10.3390/rs13030488 ◽

2021 ◽

Vol 13 (3) ◽

pp. 488

Author(s):

Aimon Tanvir ◽

Zeeshan Javed ◽

Zhu Jian ◽

Sanbao Zhang ◽

Muhammad Bilal ◽

...

Keyword(s):

Air Quality ◽

Anthropogenic Activities ◽

Anthropogenic Activity ◽

Hysplit Model ◽

Vertical Column ◽

Weekly Cycle ◽

Spring Festival ◽

Level 1 ◽

Reduced Mobility ◽

The Impact

Reduced mobility and less anthropogenic activity under special case circumstances over various parts of the world have pronounced effects on air quality. The objective of this study is to investigate the impact of reduced anthropogenic activity on air quality in the mega city of Shanghai, China. Observations from the highly sophisticated multi-axis differential optical absorption spectroscope (MAX-DOAS) instrument were used for nitrogen dioxide (NO2) and formaldehyde (HCHO) column densities. In situ measurements for NO2, ozone (O3), particulate matter (PM2.5) and the air quality index (AQI) were also used. The concentration of trace gases in the atmosphere reduces significantly during annual Spring Festival holidays, whereby mobility is reduced and anthropogenic activities come to a halt. The COVID-19 lockdown during 2020 resulted in a considerable drop in vertical column densities (VCDs) of HCHO and NO2 during lockdown Level-1, which refers to strict lockdown, i.e., strict measures taken to reduce mobility (43% for NO2; 24% for HCHO), and lockdown Level-2, which refers to relaxed lockdown, i.e., when the mobility restrictions were relaxed somehow (20% for NO2; 22% for HCHO), compared with pre-lockdown days, as measured by the MAX-DOAS instrument. However, for 2019, a reduction in VCDs was found only during Level-1 (24% for NO2; 6.62% for HCHO), when the Spring Festival happened. The weekly cycle for NO2 and HCHO depicts no significant effect of weekends on the lockdown. After the start of the Spring Festival, the VCDs of NO2 and HCHO showed a decline for 2019 as well as 2020. Backward trajectories calculated using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicated more air masses coming from the sea after the Spring Festival for 2019 and 2020, implying that a low pollutant load was carried by them. No impact of anthropogenic activity was found on O3 concentration. The results indicate that the ratio of HCHO to NO2 (RFN) fell in the volatile organic compound (VOC)-limited regime.

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Behavioral Parameters of Planarians (Girardia tigrina) as Fast Screening, Integrative and Cumulative Biomarkers of Environmental Contamination: Preliminary Results

Water ◽

10.3390/w13081077 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1077

Author(s):

Ana M. Córdova López ◽

Althiéris de Souza Saraiva ◽

Carlos Gravato ◽

Amadeu M. V. M. Soares ◽

Renato Almeida Sarmento

Keyword(s):

Water Samples ◽

Feeding Rate ◽

Anthropogenic Activities ◽

Behavioral Responses ◽

Freshwater Ecosystems ◽

Sampling Point ◽

Total Chloride ◽

Fast Screening ◽

Sampling Points ◽

The Impact

The present study aims to use behavioral responses of the freshwater planarian Girardia tigrina to assess the impact of anthropogenic activities on the aquatic ecosystem of the watershed Araguaia-Tocantins (Tocantins, Brazil). Behavioral responses are integrative and cumulative tools that reflect changes in energy allocation in organisms. Thus, feeding rate and locomotion velocity (pLMV) were determined to assess the effects induced by the laboratory exposure of adult planarians to water samples collected in the region of Tocantins-Araguaia, identifying the sampling points affected by contaminants. Furthermore, physicochemical and microbiological parameters, as well as the presence of inorganic compounds (dissolved aluminum, total barium, total chloride, dissolved iron, total fluoride, total manganese, nitrates, nitric nitrogen, total sulfate, total zinc) and surfactants, were determined on each specific sampling point. The behavioral biomarkers (feeding rate and pLMV) of the freshwater planarians were significantly decreased when organisms were exposed to water samples from four municipalities (Formoso do Araguaia, Lagoa da Confusão, Gurupi and Porto Nacional), sites of the Tocantins-Araguaia hydrographic region—TAHR. Both behavioral biomarkers decreased up to ~37–39% compared to organisms in ASTM medium only. Our results showed that these behavioral biomarkers can be used for fast screening monitoring of environmental samples of freshwater ecosystems, since a decrease in feeding rate and locomotor activity was observed in sites impacted by anthropogenic activities. However, the absence of effects observed in some sampling points does not represent the absence of contamination, since several other classes of contaminants were not determined. In these negative results, the absence of deleterious effects on behavioral biomarkers might only be indicative that the potential presence of contaminants on such sites does not significantly affect the performance of planarians. This fast screening approach seems to be useful to determine contaminated sites in freshwater ecosystems for biomonitoring purposes. This knowledge will help to develop biomonitoring programs and to decide appropriate sampling sites and analysis.

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Multi-domain probiotic consortium as an alternative to chemical remediation of oil spills at coral reefs and adjacent sites

Microbiome ◽

10.1186/s40168-021-01041-w ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Denise P. Silva ◽

Helena D. M. Villela ◽

Henrique F. Santos ◽

Gustavo A. S. Duarte ◽

José Roberto Ribeiro ◽

...

Keyword(s):

Microbial Community ◽

Coral Reefs ◽

Environmental Changes ◽

Oil Spills ◽

Anthropogenic Activities ◽

Oil Contamination ◽

Negative Effects ◽

Corexit 9500 ◽

Coral Health ◽

The Impact

Abstract Background Beginning in the last century, coral reefs have suffered the consequences of anthropogenic activities, including oil contamination. Chemical remediation methods, such as dispersants, can cause substantial harm to corals and reduce their resilience to stressors. To evaluate the impacts of oil contamination and find potential alternative solutions to chemical dispersants, we conducted a mesocosm experiment with the fire coral Millepora alcicornis, which is sensitive to environmental changes. We exposed M. alcicornis to a realistic oil-spill scenario in which we applied an innovative multi-domain bioremediator consortium (bacteria, filamentous fungi, and yeast) and a chemical dispersant (Corexit® 9500, one of the most widely used dispersants), to assess the effects on host health and host-associated microbial communities. Results The selected multi-domain microbial consortium helped to mitigate the impacts of the oil, substantially degrading the polycyclic aromatic and n-alkane fractions and maintaining the physiological integrity of the corals. Exposure to Corexit 9500 negatively impacted the host physiology and altered the coral-associated microbial community. After exposure, the abundances of certain bacterial genera such as Rugeria and Roseovarius increased, as previously reported in stressed or diseased corals. We also identified several bioindicators of Corexit 9500 in the microbiome. The impact of Corexit 9500 on the coral health and microbial community was far greater than oil alone, killing corals after only 4 days of exposure in the flow-through system. In the treatments with Corexit 9500, the action of the bioremediator consortium could not be observed directly because of the extreme toxicity of the dispersant to M. alcicornis and its associated microbiome. Conclusions Our results emphasize the importance of investigating the host-associated microbiome in order to detect and mitigate the effects of oil contamination on corals and the potential role of microbial mitigation and bioindicators as conservation tools. Chemical dispersants were far more damaging to corals and their associated microbiome than oil, and should not be used close to coral reefs. This study can aid in decision-making to minimize the negative effects of oil and dispersants on coral reefs.

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Unele aspecte metodologice de studiu a biodiversitatii si productivitatii fitocenozelor din cadrul ecosistemelor urbane

Impactul antropic asupra calitatii mediului ◽

10.53380/9789975330800.07 ◽

2019 ◽

Author(s):

Constantin Bulimaga ◽

◽

Anastasia Portarescu ◽

Keyword(s):

Riparian Vegetation ◽

Anthropogenic Activities ◽

Natural Ecosystems ◽

Impact Action ◽

Productive Potential ◽

Study Methodology ◽

Biodiversity Study ◽

The Impact ◽

The City ◽

Urban Activities

Anthropogenic activities cause damage to the natural ecosystems in the city in various ways, which contributes to the reduction of biodiversity. Considering that biodiversity is becoming more vulnerable to the impact action triggered by urban activities is necessary to monitor it in order to take urgent measures to protect and preserve it. The plant biodiversity study methodology includes methods that help determine phytocenosis parameters and assess biomass in order to estimate the productive potential of phytocenosis. Carrying out the research according to the proposed methodology will make it possible to assess the anthropogenic impact on the terrestrial and riparian vegetation.

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Assessing the impact of exceptional inter-annual climatic variability on rates of net ecosystem carbon dioxide exchange at Clara bog.

10.5194/egusphere-egu21-13414 ◽

2021 ◽

Author(s):

Matthew Saunders ◽

Ruchita Ingle ◽

Shane Regan

Keyword(s):

Water Table ◽

Elevated Temperatures ◽

Ecosystem Respiration ◽

Anthropogenic Activities ◽

Climatic Variability ◽

Growing Season ◽

Carbon Dioxide Exchange ◽

Mean Annual Temperature ◽

Monitoring Networks ◽

The Impact

Peatland ecosystems are integral to the mitigation of climate change as they represent significant terrestrial carbon sinks. In Ireland, peatlands cover ~20% of the land area but hold up to 75% of the soil organic carbon stock however many of these ecosystems (~85% of the total area) have been degraded due to anthropogenic activities such as agriculture, forestry and extraction for horticulture or energy. Furthermore, the carbon stocks that remain in these systems are vulnerable to inter-annual variation in climate, such as changes in precipitation and temperature, which can alter the hydrological status of these systems leading to changes in key biogeochemical processes and carbon and greenhouse gas exchange.&#160; During 2018 exceptional drought and heatwave conditions were reported across Northwestern Europe, where reductions in precipitation coupled with elevated temperatures were observed. Exceptional inter-annual climatic variability was also observed at Clara bog, a near natural raised bog in the Irish midlands when data from 2018 and 2019 were compared. Precipitation in 2018 was ~300 mm lower than 2019 while the average mean annual temperature was 0.5&#176;C higher. The reduction in precipitation, particularly during the growing season in 2018, consistently lowered the water table where ~150 consecutive days where the water table was >5cm below the surface of the bog were observed at the central ecotope location. The differing hydrological conditions between years resulted in the study area, as determined by the flux footprint of the eddy covariance tower, acting as a net source of carbon of 53.5 g C m-2 in 2018 and a net sink of 125.2 g C m-2 in 2019. The differences in the carbon dynamics between years were primarily driven by enhanced ecosystem respiration (Reco) and lower rates of Gross Primary Productivity (GPP) in the drier year, where the maximum monthly ratio of GPP:Reco during the growing season was 0.96 g C m-2 month in 2018 and 1.14 g C m-2 month in 2019. This study highlights both the vulnerability and resilience of these ecosystems to exceptional inter-annual climatic variability and emphasises the need for long-term monitoring networks to enhance our understanding of the impacts of these events when they occur.

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Biogeochemical and ecological features of sinking particulate matter in the deep Ionian Sea (E. Mediterranean) during a 10-year time series study: impacts of atmospheric and oceanographic variabilities on carbon production and sequestration

10.5194/egusphere-egu21-15201 ◽

2021 ◽

Author(s):

Alexandra Gogou ◽

Constantine Parinos ◽

Spyros Stavrakakis ◽

Emmanouil Proestakis ◽

Maria Kanakidou ◽

...

Keyword(s):

Particulate Matter ◽

Organic Carbon ◽

Carbon Cycle ◽

Atmospheric Deposition ◽

Water Column ◽

Particulate Organic Carbon ◽

Nutrient Dynamics ◽

Ionian Sea ◽

Ecological Features ◽

The Impact

Biotic and abiotic processes that form, alter, transport, and remineralize particulate organic carbon, silicon, calcium carbonate, and other minor and trace chemical species in the water column are central to the ocean&#8217;s ecological and biogeochemical functioning and of fundamental importance to the ocean carbon cycle. Sinking particulate matter is the major vehicle for exporting carbon from the sea surface to the deep sea. During its transit towards the sea floor, most particulate organic carbon (POC) is returned to inorganic form and redistributed in the water column. This redistribution determines the surface concentration of dissolved CO2, and hence the rate at which the ocean can absorb CO2 from the atmosphere. The ability to predict quantitatively the depth profile of remineralization is therefore critical to deciphering the response of the global carbon cycle to natural and human-induced changes.Aiming to investigate the significant biogeochemical and ecological features and provide new insights on the sources and cycles of sinking particulate matter, a mooring line of five sediment traps was deployed from 2006 to 2015 (with some gap periods) at 5 successive water column depths (700, 1200, 2000, 3200 and 4300 m) in the SE Ionian Sea, northeastern Mediterranean (&#8216;NESTOR&#8217; site). We have examined the long-term records of downward fluxes for Corg, Ntot, &#948;13Corg and &#948;15Ntot, along with the associated ballast minerals (opal, lithogenics and CaCO3), lipid biomarkers, Chl-a and PP rates, phytoplankton composition, nutrient dynamics and atmospheric deposition. &#160;The satellite-derived seasonal and interannual variability of phytoplankton metrics (biomass and phenology) and atmospheric deposition (meteorology and air masses origin) was examined for the period of the sediment trap experiment. Regarding the atmospheric deposition, synergistic opportunities using Earth Observation satellite lidar and radiometer systems are proposed (e.g. Cloud&#8208;Aerosol Lidar with Orthogonal Polarization - CALIOP, Moderate Resolution Imaging Spectroradiometer - MODIS), aiming towards a four&#8208;dimensional exploitation of atmospheric aerosol loading (e.g. Dust Optical Depth) in the study area.Our main goals are to: i) develop a comprehensive knowledge of carbon fluxes and associated mineral ballast fluxes from the epipelagic to the mesopelagic and bathypelagic layers, ii) elucidate the mechanisms governing marine productivity and carbon export and sequestration to depth and iii) shed light on the impact of atmospheric forcing and deposition in respect to regional and large scale circulation patterns and climate variability and the prevailing oceanographic processes (internal variability).AcknowledgmentsWe acknowledge support of this work by the Action &#8216;National Network on Climate Change and its Impacts &#8211; CLIMPACT&#8217;, funded by the Public Investment Program of Greece (GSRT, Ministry of Development and Investments).

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Geospatial technology perspectives for mining vis-a-vis sustainable forest ecosystems

Present Environment and Sustainable Development ◽

10.1515/pesd-2017-0020 ◽

2017 ◽

Vol 11 (1) ◽

pp. 219-238 ◽

Cited By ~ 5

Author(s):

Laxmi Goparaju ◽

P. Rama Chandra Prasad ◽

Firoz Ahmad

Keyword(s):

Forest Ecosystems ◽

Anthropogenic Activities ◽

Biogeochemical Cycles ◽

Mining Activities ◽

Forest Environment ◽

Mining Operations ◽

Geospatial Technology ◽

The Status ◽

The Impact

Abstract Forests, the backbone of biogeochemical cycles and life supporting systems, are under severe pressure due to varied anthropogenic activities. Mining activities are one among the major reasons for forest destruction questioning the survivability and sustainability of flora and fauna existing in that area. Thus, monitoring and managing the impact of mining activities on natural resources at regular intervals is necessary to check the status of their depleted conditions, and to take up restoration and conservative measurements. Geospatial technology provides means to identify the impact of different mining operations on forest ecosystems and helps in proposing initiatives for safeguarding the forest environment. In this context, the present study highlights the problems related to mining in forest ecosystems and elucidates how geospatial technology can be employed at various stages of mining activities to achieve a sustainable forest ecosystem. The study collates information from various sources and highlights the role of geospatial technology in mining industries and reclamation process.

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Trophic and functional organization of the benthic macrofauna in the lagoon of Boughrara – Tunisia (SW Mediterranean Sea)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315414001544 ◽

2014 ◽

Vol 95 (4) ◽

pp. 647-659 ◽

Cited By ~ 11

Author(s):

Ines Khedhri ◽

Hanem Djabou ◽

Ahmed Afli

Keyword(s):

Functional Organization ◽

Anthropogenic Activities ◽

Benthic Macrofauna ◽

Anthropogenic Factors ◽

Deposit Feeders ◽

Trophic Resources ◽

Open Sea ◽

Seasonal Monitoring ◽

Lagoon Environment ◽

The Impact

The lagoon of Boughrara is the largest lagoon in Tunisia. For several decades it has been subject to the impact of increasing anthropogenic activities, and also to environmental stressors due to climate change and the low renewal of its waters. The present work is a contribution to the study of the functional organization of the benthic macrofauna of the lagoon of Boughrara 3 years after the extension of the channel ‘El Kantra’ which connects this lagoon to the open sea. In total, 13 stations facing the main prospective sources of disturbance and in areas likely to be more polluted were seasonally sampled during 2009–2010. Seasonal monitoring of the abiotic parameters shows a spatial heterogeneity linked to environmental and anthropogenic factors, including hydrodynamics, sedimentary texture and anthropogenic activities. The community of benthic macrofauna is generally poorly diversified at lagoonal-marine stations undergoing influences of both the marine and lagoon environment. The extreme seasons in terms of temperature and salinity seem to have an important role in the reduction of biodiversity in the lagoon of Boughrara. The trophic structure of the macrobenthic community is generally dominated by selective deposit feeders, and seems to be linked more to the availability of trophic resources than to disturbance.

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