Environmental Science

Integrated constructed wetlands for rural domestic wastewater treatment: A full-scale study in Ireland

by Mawuli Dzakpasu

Mawuli Dzakpasu, Valerie McCarthy, Miklas Scholz, Siobhán N. Jordan
World congress on Water, Climate and Energy, International Water Association, Dublin, Ireland, May 13-18, 2012.

Abstract
The paper reports the treatment performance capability, during an on-going full-scale study, which was... more Abstract
The paper reports the treatment performance capability, during an on-going full-scale study, which was set to evaluate the novel concept of integrated constructed wetlands (ICW) for domestic wastewater treatment in Ireland. The ICW at the center of this study is located at Glaslough in Co. Monaghan, Ireland. The 3.25 ha ICW comprises of two sludge cells and a sequence of five shallow vegetated wetland cells, and receiving primary domestic wastewater. Overall, mass removal rates greater than 90% were achieved for suspended solids, organic matter and nutrients during the monitoring period (February 2008 to June 2011). A direct correlation of organic loading on its removal rates was sustained over the entire period of monitoring, and indicated that the ICW had capacity for increased organic loads and could still be operated beyond the maximum ranges received during the course of this study. Nutrients removal, however, was slightly variable. Kinetic coefficients estimated for nutrients removal in the ICW indicated that nutrients removal was largely dependent on temperature, and showed a reduced removal rate under freezing conditions and under higher hydraulic loading rates. Enlarging the system to provide a longer hydraulic retention time can therefore, optimize the nutrient removal during such periods.

A GIS Comparative Analysis of Bronze Age Settlement Patterns and the Contemporary Physical Landscape in the Jazira Region of Syria

by Tony Mathys

Most of the datasets presented in this thesis are available for free in ArcGIS shapefile format on the ShareGeo Open data repository at http://www.sharegeo.ac.uk/.

These datasets are available for everyone to use as it is important to encourage data sharing in support of research activities.

There are also some CORONA satellite images available on ShareGeo for the Syrian Jazira region. The plan is to eventually provide complete CORONA coverage for this region, though geo-referencing will not be precise as it's intended to be more for user orientation.

Acknowledgement should go to the U.S. Geological Survey (USGS), which makes CORONA imagery available via its EarthExplorer online data service at http://edcsns17.cr.usgs.gov/NewEarthExplorer/
Many CORONA images are available to download for free from this service, though require processing and geo-referencing for use in a GIS or a software package for processing remotely sensed imagery.

Relevant to this, and the thesis, is the following paper presented which first introduced how CORONA satellite imagery could be applied to archaeological work in the Near East. Martin Fowler also wrote about the potential of CORONA in the Aerial Archaeology Research Group (AARG) news.

Mathys, Tony. “The Use of Declassified Intelligence Satellite Photographs in a GIS (IDRISI) to Map Archaeological Sites and the Surrounding Landscape in the Northeastern Region of the Syrian Jazirah. The University of Chicago Oriental Institute, NASA and St. Cloud State University Remote Sensing Applications in Archaeology Conference. St. Cloud, Minnesota, May 29-31, 1997.

Unfortunately, papers presented at this conference were not published.

My gratitude and thanks to Dr Sarah Parcak for citing this unpublished conference paper in her book (Satellite Remote Sensing in Archaeology), and to Dr Aled Rowlands and Dr Apostolos Sarris for citing it in their Journal of Archaeological Science article 34 (2007).

A Cloud-based Virtual Observatory for Environmental Science

by Yehia El-khatib

Kalogiannakis, M., Rekoumi, Ch., & Chatzipapas C. (2011). Preschool education and geology in the framework of environmental education: a didactic proposal, In K. Plakitsi (ed.) Sociocognitive and Sociocultural Approaches to Science in Early Childhood, 224-235, Athens: Patakis (in Greek).

by Michail Kalogiannakis

Greece is a country with a wide variety of geological formations that make up the rich geodiversity and determine the... more Greece is a country with a wide variety of geological formations that make up the rich geodiversity and determine the value of its geological heritage. The environmental education raises as a result of retraining courses dealing with objects of various sciences. Scientific knowledge is used globally for the holistic approach to environmental problems. As part of this research by studying the literature of this field we present a proposal for the use of geology, by teaching through respective myths in kindergarten under the scope of environmental education. In Greek mythology there is a strong presence of geological phenomena such as earthquakes, volcanoes, hot springs, whose interpretation was given in a supernatural way. The interpretations of geological phenomena were enriched with social elements of that era and became myths, where dominated the primitive belief that the nature is governed by spontaneous and capricious deities that caν use them.
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Καλογιαννάκης, Μ., Ρεκούμη, Χ., & Χατζηπαπάς, Κ. (2011). Προσχολική εκπαίδευση και Γεωλογία στα πλαίσια της περιβαλλοντικής εκπαίδευσης: μια διδακτική πρόταση, στο Κ. Πλακίτση (επιμ.) Κοινωνιογνωστικές και κοινωνικοπολιτισμικές προσεγγίσεις στη διδακτική των φυσικών επιστημών στην προσχολική και πρώτη σχολική ηλικία, 224-235, Αθήνα: Πατάκης.

Η Ελλάδα είναι μια χώρα με μεγάλη ποικιλία γεωλογικών σχηματισμών, οι οποίοι συνθέτουν την πλούσια γεωποικιλότητά της και προσδιορίζουν την αξία της γεωλογικής κληρονομιάς της. Η περιβαλλοντική εκπαίδευση προβάλλει ως το αποτέλεσμα του επαναπροσανατολισμού των μαθημάτων που ασχολούνται με αντικείμενα διαφόρων επιστημών. Η επιστημονική γνώση χρησιμοποιείται συνολικά για τη σφαιρική προσέγγιση των περιβαλλοντικών προβλημάτων. Στην παρούσα έρευνα, μέσα από τη μελέτη της σχετικής βιβλιογραφίας του πεδίου, παρουσιάζουμε μια διδακτική πρόταση για τη χρήση της γεωλογίας, μέσω της διδασκαλίας των αντίστοιχων μύθων, στο νηπιαγωγείο στο πλαίσιο της περιβαλλοντικής εκπαίδευσης. Στην ελληνική μυθολογία είναι έντονη η παρουσία γεωλογικών φαινομένων όπως οι σεισμοί, τα ηφαίστεια, οι θερμές πηγές, των οποίων η ερμηνεία δινόταν με υπερφυσικό τρόπο. Οι ερμηνείες αυτές εμπλουτισμένες με κοινωνικά στοιχεία της εποχής αποτέλεσαν τους μύθους, μέσα στους οποίους κυριαρχεί η πρωτόγονη πεποίθηση ότι τη φύση κυβερνούν αυθόρμητες και ιδιότροπες θεότητες που προκαλούν τα διάφορα γεωλογικά φαινόμενα.

Assessing Decentralized Wastewater Treatment Options in Santa Barbara County

by Geneva Travis

One potential solution to address this water shortage is reducing demand through recycling water. Decentralized... more One potential solution to address this water shortage is reducing demand through recycling water. Decentralized wastewater treatment can provide high quality,recycled water on site, but these technologies are scarce in Santa Barbara County dueto a lack of familiarity. We partnered with The Sustainability Project, a Santa Barbara based non-profit, to develop a decision support tool for architects and builders tolearn about and compare systems, and to assist them in identifying appropriate wastewater treatment systems for their projects. We then applied our tool to a project for Peikert Group Architects that faced strict wastewater restrictions. Additionally, we analyzed the life cycle global warming impacts of centralized and decentralized systems, including sewage collection, to comprehensively evaluate their impacts.Lastly, we created a decentralized wastewater treatment permitting flowchart to guide stakeholders through the complex regulatory process. Our project provides a thorough analysis of the strengths and weaknesses of various decentralized wastewater systems from an environmental, economic, and social perspective. Our analysis shows that there is no perfect technology since trade-offs exist between different criteria, and that obtaining a permit for advanced decentralized wastewater treatment systems is difficult. Information is presented in an accessible manner to stakeholders, preparing them to meet the sustainable design challenges of the future.

Influence of stormwater infiltration on the treatment capacity of a LECA-based horizontal subsurface flow constructed wetland

by Antonio Albuquerque

L. Amado, A. Albuquerque, A. Espirito Santo
Ecological Engineering, 2012, V. 39, 16-23.

This research work evaluates the impact of stormwater infiltration on the removal of organics, solids, nitrogen and... more This research work evaluates the impact of stormwater infiltration on the removal of organics, solids, nitrogen and phosphorus in a LECA-based horizontal subsurface flow constructed wetland. Stormwater runoff for the period between January 2008 and June 2010 (30 months) was estimated for the drainage basin of the Vila Fernando wastewater treatment plant (constructed wetland system) and it was observed proportionality between the increase in surface runoff and the infiltration flow rate that reached the plant. The average stormwater infiltration rate that reached the plant was 67.4 m(3) d(-1) (77% of the influent flow rate into the plant). The 30 month monitoring campaign set up at one of the reed beds showed that stormwater infiltration led to a high variation of the hydraulic loading rate (HLR) throughout the bed, which affected its performance in the removal of organic matter, suspended solids and nitrogen. For a HLR below 20 cm d-1 the removal efficiencies for BOD5, COD and TSS doubled. The removal of nitrogen was too low and was associated with the weak development of nitrifying biofilm and the poor growth of reeds. However, it was observed a good relationship between the applied and removed loads for most of the parameters, which seems to indicate that the organic, solid, nitrogen and phosphorus loading rates influenced the respective removal rates. The use of a bed material with high specific surface area, such as LECA, can only improve the treatment capacity of horizontal subsurface flow systems if the organic and solid loading rates, as well as the HLR, can be effectively controlled.

The influence of plants on nitrogen removal from landfill leachate in discontinuous batch shallow constructed wetland with recirculating subsurface horizontal flow

by Antonio Albuquerque

A. Białowiec, L. Davies, A. Albuquerque, P. Randerson
Ecological Engineering, 2012, V. 40, 44-52

Three discontinuous batch shallow constructed wetland systems with recirculating subsurface horizontal flow with reed,... more Three discontinuous batch shallow constructed wetland systems with recirculating subsurface horizontal flow with reed, willow, and without plants were used to assess the removal of nitrogen from landfill leachate in relation to hydraulic retention time and climatic conditions. In all systems redox potential in the beds increased asymptotically from negative anoxic conditions to +67 (reed bed), −2 (willow bed), and +17 mV (control bed), reaching a plateau in two wk. During the first 24 h after feeding the beds all forms of nitrogen decreased significantly. It has been shown that plants release O2 and Norg which was then hydrolyzed to ammonia. Plant-available radiation significantly (p < 0.05) increased the release of Norg and removal of ammonia after the 9th day of the experiment. Low, and relatively constant concentrations of nitrite and nitrate indicated that denitrification had taken place in the beds.

Potential for reuse of tungsten mining waste-rock in technical-artistic value added products

by Antonio Albuquerque

J. Castro-Gomes, A. Silva, R. Cano, J. Suarez, A. Albuquerque
Journal of Cleaner Production, 2012, V. 25, 34-41

Mining and quarrying activities in Europe generate approximately 55% of total industrial wastes, according to a recent... more Mining and quarrying activities in Europe generate approximately 55% of total industrial wastes, according to a recent Eurostat report. Most of these wastes are directly dumped on land or deposited in landfill sites. The first solution may lead to negative environmental impacts on land (removal of vegetation, deforestation, land slope changes and increased risk of erosion), water (pollutant transport through surface runoff, soil infiltration and contamination of water resources), may lead to the contamination of agricultural goods and may impose risks on human health. In Portugal, about 20% of industrial waste produced originates from mines and quarries, particularly from Panasqueira mining, one of the largest tungsten mines in the world. Currently, Panasqueira mining generates almost 100 tonnes of waste-rock, per day. Such waste-rock have accumulated over a number of years into very large heaps and it is desirable to seek new economic solutions that can contribute towards their reuse. In this context, this work discusses the potential for reuse of waste-rock piles of Panasqueira tungsten mine, which may be a case statement to be followed. The proposed solution described in this paper consists in developing innovative polymer-based composite materials, obtained from non-contaminated waste-rock tailings. Such materials must have suitable properties for technical-artistic value added applications, such as conservation, restoration and/or rehabilitation of historic monuments, sculptures, decorative and architectural intervention, or simply as materials for building revetments.

Nitrogen removal from landfill leachate in constructed wetlands with reed and willow: Redox potential in the root zone

by Antonio Albuquerque

A. Białowiec, L. Davieis, A. Albuquerque, P. Randerson
Journal of Environmental Management, 2012, V. 97, 22–27

This study investigated the effects of reed and willow on bioremediation of landfill leachate in comparison with an... more This study investigated the effects of reed and willow on bioremediation of landfill leachate in comparison with an unplanted control by measuring redox potential levels in the rhizosphere of microcosm systems in a greenhouse. Plants had a significant influence on redox potential relative to the plant-less system. Redox potential in the reed rhizosphere was anoxic (mean −102 ± 85 mV), but it was the least negative, being significantly higher than in the willow (mean −286 ± 118 mV), which had the lowest Eh. Redox potential fluctuated significantly in the willow rhizosphere during daylight hours, with large decreases in the morning. Levels of NH4+ decreased significantly in the first day of the experiment and remained at similar low levels in all three variants for the next four weeks of the experiment. Following this removal of ammonia significant peaks in NO2− occurred in the control and reed tanks on the 1st day, and again on 14th day in the control tank up to 13 mg/dm3. In the willow tank there was also one significant peak of NO2− in the first week, but only up to 0.5 mg/dm3. Significant accumulation, within 21 days of NO3− in all variants was observed, but in tanks with reed and willow the concentration of NO3− remained significantly lower (<4 mg/dm3) than in the unplanted tank (∼35 mg/dm3). Final levels of total-nitrogen, nitrate and chemical oxygen demand were considerably lower in the reed and willow tank than in the unplanted tank.

Mineral wastes geopolymeric artificial aggregates as alternative materials for wastewater-treatment processes - Study of structural stability and pH variation in water

by Antonio Albuquerque

Silva I., Castro-Gomes J. & Albuquerque A.
Journal of Materials in Civil Engineering, V. 24, Nº 6, 1-6.

Artificial aggregates produced from mine waste geopolymeric binders were studied as a potential substrate for... more Artificial aggregates produced from mine waste geopolymeric binders were studied as a potential substrate for fixed-film
wastewater-treatment processes (biofilm reactors). Waste geopolymeric artificial aggregates (WGA) of 2–3 cm in size were produced using geopolymeric mine waste mud as a precursor and both sodium silicate and sodium hydroxide as alkaline activators. Seven mixtures were produced with different atomic ratios of sodium silicate to sodium hydroxide (S/H) and of precursor (waste mud) to sodium silicate (P/S), using curing temperatures of 20°C and 130°C, for a total of 112 samples. Structural stability and pH variation after immersion in water were observed over an 18-week period. The results showed that the initial water pH decreased with the increase of the curing time, taking between 17 and 42 days to reach pH 8. The mixture cured at 20°C for 28 days appears to be suitable for use as a substrate for biofilm reactors because the initial water pH was one of the lowest (approximately pH 10), and the time necessary to stabilize it to approximately pH 8 was only 17 days.

Effect of immersion in water partially alkali-activated materials obtained of tungsten mine waste mud

by Antonio Albuquerque

Silva I., Castro-Gomes J. & Albuquerque A.
Construction and Building Materials, V. 35, 117-124.

Alkali-activated binders can be obtained using several sources of alumino-silicate materials, from calcinatedmore Alkali-activated binders can be obtained using several sources of alumino-silicate materials, from calcinated
clays, like kaolin, to industrial by-products, such as fly ash and, more recently, to calcinated waste mud from mining activities. The technology to obtain alkali-activated binders, also designated as geopolymers, is gaining increasing interest, since, in some cases, the properties of geopolymeric materials
are superior to other existing cementitious systems. The research presented in this paper intends to deepen
the knowledge regarding the properties of geopolymeric materials obtained using tungsten mining waste mud, particularly to study its behaviour after being immersed in water. However, in the current work, focus is given to follow compressive strength results in partially alkali-activated samples immersed in water, during different curing periods of time. Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy analysis (FTIR) were also utilised to investigate changes in the microstructure at different conditions of water immersion. A significant decrease in compressive strength occurring after 24 h of immersion in water was found out, of specific partially alkali-activated materials, despite of its initial high compressive strength after 35 days curing, at different temperatures.

Hydrological and Water Quality Characterisation of a Tropical Riverine Wetland: Nabajjuzi-Masaka, Uganda

by Najib Lukooya Bateganya

Abstract
In East Africa where wetlands are becoming essential systems for waste water treatment and potable... more Abstract
In East Africa where wetlands are becoming essential systems for waste water treatment and potable water supply, hydrological characterisation is crucial to understand the dynamics of their functioning on a spatial and temporal scale. Beside ecosystem services, basic ecological properties such as vegetation structure and nutrient cycling of wetland ecosystems depend on hydrology. Nabajjuzi wetland, in central Uganda, East Africa is internationally recognised as a Ramsar site and currently used for potable water supply in addition to other essential ecological and social economic services to the riparian communities. To contribute to the limited and scanty information of this ecosystem, the study focussed on hydrological and water quality characterisation using a water-nutrient mass balance as the major output. Also, the flow dynamics of Fe and allochthonous suspended solids loading into the wetland were investigated.

Results show that the water balance of Nabajjuzi wetland is dominated by surface flow, which is influenced by rainy and dry periods. During peak flow, the estimated hydraulic retention time was found to be 1 month compared to 1.5 months during the low flow period. Also, water loss flux due to evapotranspiration in this region is high and in Nabajjuzi wetland, it is twice the daily rate of abstraction. Analysis of long term flow data also revealed that the current water abstraction rate can potentially result in hydrological stress to the system during extremely low flow periods. However, the wetland N and P loading is very low compared to other urban disturbed wetlands. Consequently, high concentration of Fe and suspended solids loading are the major constraints to the surface water quality hence potable water supply. Generally, there is need for a more comprehensive hydrological-water quality study and careful planning of the future catchment land use strategies. This can enhance management and conservation of the wetland to guarantee the crucial ecosystem services it provides.

Keywords: Hydrology, Riverine wetland, Hydrological gradient, Surface-flow, Nutrients, Iron, Mass-balance, Lake Victoria basin.

Variation of water quality across Cooum river in Chennai city

by Abraham Samuel

Published in 'Journal of Journal of Environment and Earth Science',
April 2012

The huge demand for freshwater resources in the 21st century can be attributed to population growth, advanced... more The huge demand for freshwater resources in the 21st century can be attributed to population growth, advanced agricultural practices and industrial usages. This study attempts to evaluate the water quality of Cooum river across Chennai, and was carried out by systematic collection and analysis of 5 water samples from 5 regions. Samples collected at some parts of the city were even found to be not fit for irrigation as they had high acidity, low dissolved oxygen and high amount of dissolved solids. Some samples were also found to have certain microbes which pose health hazards when ingested. The major contaminant sources identified in the areas were the samples were polluted were liquid and solid wastes, discharges from factories and refineries, drainage of sewage, and brine water in estuaries.

Selection of active air samplers

by Tim Sandle

Coastal Systems - Korean translation

by Simon Haslett

My Coastal Systems textbook is now available in Korean.

Cycling DDT and homologues at basin scale: the case of Lake Maggiore.

by pietro volta

Galassi, S., P. Volta, L.Guzzella & A. Calderoni. 2006. Journal of Limnology, 65(2): 100-106.

Identification of a new type of ecological hazard of chemicals: inhibition of processes of ecological remediation

by Sergei Ostroumov

Heavy metals and trace elements in atmospheric fall-out: Their relationship with topsoil and wheat element composition

by Gonzalo Bermudez

Journal of Hazardous Materials, In press (Available online 16 February 2012)

The objectives of this study were to determine the average concentrations and deposition rates of 28 elements in... more The objectives of this study were to determine the average concentrations and deposition rates of 28 elements in atmospheric bulk deposition and to elucidate associations among topsoil, bulk deposition and wheat element composition. The fluxes of arsenic (As), copper (Cu), lead (Pb) and zinc (Zn) deposition in Córdoba were higher than in other agro-ecosystems, which reflects both natural (geochemistry and topsoil removal) and anthropogenic sources. High lanthanide, uranium (U) and thorium (Th) concentrations revealed the impact of an open cast uranium mine. The highest enrichment factors (EF) were those of Cu, Pb, Zn and nickel (Ni), with calcium (Ca) being the most prominent in the surroundings of a cement plant. Industries and the transport of airborne urban pollutants were the main anthropogenic sources for Ca, Cu, Ni, Pb, Zn, cadmium (Cd), iron (Fe), manganese (Mn) and antimony (Sb). The concentrations of metals in wheat grain were predicted using the topsoil and atmospheric fall-out composition with R2 = 0.90, with the latter being the best explanatory variable. The present study highlights the potential health hazards of wheat consumption (Environmental Protection Agency) by the assessment of heavy metals in bulk atmospheric deposition.

Combination of a higher-tier flow-through system and population modeling to assess the effects of time-variable exposure of isoproturon on the green algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata

by Thomas G. Preuss

    Denis Weber, Dieter Schaefer, Michael Dorgerloh, Eric Bruns, Gerhard Goerlitz, Klaus Hammel, Thomas G. Preuss & Hans Toni Ratte
Environmental Toxicology and Chemistry, in press

A flow-through system was developed to investigate the effects of time-variable exposure of pesticides on algae. A... more A flow-through system was developed to investigate the effects of time-variable exposure of pesticides on algae. A recently developed algae population model was used for simulations supported and verified by laboratory experiments. Flow-through studies with Desmodesmus subspicatus and Pseudokirchneriella subcapitata under time-variable exposure to isoproturon were performed, in which the exposure patterns were based on the results of FOrum for Co-ordination of pesticide fate models and their USe (FOCUS) model calculations for typical exposure situations via run-off or drain flow. Different types of pulsed exposure events were realized, including a whole range of repeated pulsed and steep peaks as well as periods of constant exposure. Both species recovered quickly in terms of growth from short-term exposure and according to substance dissipation from the system. Even a peak at 10 times the maximum predicted environmental concentration of isoproturon, there were only transient effects on algae populations. No modified sensitivity or reduced growth was observed after repeated exposure. Model predictions of algal growth in the flow-through tests agreed well with the experimental data. The experimental boundary conditions and the physiological properties of the algae were used as the only model input. No calibration or parameter fitting was necessary. The combination of the flow-through experiments with the algae population model turned out to be a powerful tool for the assessment of pulsed exposure on algae. It allowed investigating the growth reduction and recovery potential of algae after complex exposure, which is not possible with standard laboratory experiments alone. The results of the combined approach confirm the beneficial use of population models as supporting tools in higher-tier risk assessments of pesticides.

The global distribution of net primary production: resolving the paradox

by Steve Wolverton

Huston & Wolverton 2009

The distribution of the diversity and abundance of life on Earth is thought to be shaped by the patterns of plant... more The distribution of the diversity and abundance of life on Earth is thought to be shaped by the patterns of plant growth (net primary production, NPP) in the oceans and on land. The well-known latitudinal gradient of species diversity reaches its maximum in tropical rain forests, which are considered to be the most productive ecosystems on the planet. However, this high tropical productivity on land is the opposite of the well-documented distribution of marine productivity, which is greatest in the high-latitude oceans around the poles. This paradox can be resolved by a reevaluation of the terrestrial productivity gradient. Compilations of direct measurements of forest NPP show that annual NPP in tropical forests is no different than annual NPP in temperate forests, contrary to recent syntheses and to the output of global vegetation models. Other properties of forest ecosystems, such as basal area of trees, wood density, and the ratio of wood to leaf production, as well as animal properties such as body size, population density, and reproductive rates, support the conclusion that ecologically relevant terrestrial productivity is actually highest in the temperate latitudes, reaching a maximum between 30° and 50° before declining toward the poles. This “reversal” of the latitudinal productivity gradient, if substantiated by a systematic global sampling effort, will necessitate a major reevaluation of ecological and evolutionary theory, as well as conservation strategies and international development policies.