Free Carbon Dioxide Research Articles

Occurrence of <i>Microcystis</i> <i>aeruginosa</i> Kütz. Water Blooms in a Eutrophic Pond of Chidambaram Taluk

The occurrence and abundance of Microcystisaeruginosa were monitored monthly in eutrophic pond water of Ilamiyakkinar temple pond from July 2014 to June 2015. Some environmental factors such as water temperature, pH, free carbon-dioxide (FCO2), total alkalinity, Dissolved oxygen (DO2), biological oxygen demand (BOD), nitrate (NO2-N) and phosphate are recorded and their relationship with the bloom formation by Microcystisaeruginosa were discussed. The initiation and persistence of Microcystisaeruginosa were founded to be triggered by relatively high water temperature (24 °C to 36.5 °C), pH (7.3 to 8.72) and NO2-N concentration.

Dynamics of Micro Algae in Relation to Water Quality Parameters of Pasupatheswarar Temple Pond, Annamalai Nagar, Tamil Nadu

The current study deals with water quality variations and micro algal community structure in the highly eutrophic pond. Several water quality parameters were evaluated during the period from July 2014 to June 2015 from sampling station sited from Annamalai Nagar viz., Pasupatheswarar temple pond. The water quality parameters like Air and water temperature, turbidity, electrical conductivity, total dissolved solids, total alkalinity, pH, free carbon-dioxide, dissolved oxygen, biological oxygen demand (BOD), chemical oxygen demand (COD), calcium, magnesium, phosphate and nitrate were analysed. A total 29 species were observed during the study period of which 11 species from the class Cynophyceae, 9 species from the class Chlorophyceae, 6 species from the class Bacillariophyceae and 3 species from the class Euglenophyceae. Maximum species of the class Cyanophyceae were observed during study period. The Microcystisaeruginosa species observed in the pond indicates the signs of eutrophication of pond. The water quality parameters such as temperature, alkalinity, phosphate and nitrates are favourable for the growth of phytoplankton.

Effect of reusing the advanced-softened, silica-rich, oilfield-produced water (ASOW) on finned tubes in steam-injection boiler

For reducing environmental pollution and saving water resources, ASOW is reused as boiler feedwater. One of key challenges for that is deposition in finned tubes, which is detrimental to thermal efficiency of boiler. To evaluate the reuse and explore the formation mechanism of deposition, a 16-month pilot-scale test was conducted. Silicon content and total hardness in ASOW were 238.93mg/L and 0.031mg/L, respectively. The corrosivity of ASOW was severe by electrochemical workstation. Morphology and composition of deposition were determined by scanning electron microscope-energy dispersive spectrometer (SEM-EDS), inductively coupled plasma-mass spectroscopy (ICP-MS), X-ray diffraction (XRD), laser Raman spectrum (LRS), and Fourier transform infrared spectroscopy (FTIR). These were measured both during the early stage of steam injection (ESSI) and later stage of steam injection (LSSI). Silicates were negligible, whereas siderite (FeCO3), iron oxide (Fe2O3), and pyrite (FeS2) were main crystalline phases indicating that deposition was mainly composed of corrosion products. Besides, Fe-carbonyl complexes were identified in LSSI, indicating that some organic substance have reacted with Fe during boiler operating. It is concluded that the formation of deposition is attributed to the dissolved oxygen and free carbon-dioxide in ASOW not to silicates. However, these can offer a reference for improving the reuse.

Seasonal study of physico-chemical parameters of Kalisarar dam reservoir of Gondia district

The precipitation which is the main source of water gets contaminated as soon as it reaches on the earth's surface. During its flow anthropogenic activities in the surrounding area add further impurities in it. Flow of rivers become impeded and are regulated due to construction of dam. This brings about changes in abiotic and biotic factors compared to untamed rivers. The response of each river to dam differs. The present study was aimed to analyze the physico-chemical parameters of the Kalisarar dam reservoir carried out from the month of June 2012-May 2013. The sampling stations were divided by a measurable distance and samples were collected every month. The parameters such as temperature, pH, conductivity, dissolved oxygen, free carbon dioxide and turbidity were analysed. The paper highlights the condition of the reservoir in various seasons with respect to parameters mentioned above.

Some limnological characteristics of Dhaka-Narayangonj-Demra dam canal, Bangladesh

Some limnological parameters of water of Dhaka-Narayongonj-Demra (DND) dam canal were studied for one year period from May 2010 to April 2011. Sampling points were selected on the basis of human activities around the dam. The maximum water temperature was recorded in May 2010 (31.5 ± 0.2041°C) and minimum in December 2010 (18.3 ± 0.1925°C). Water transparency was highest in February 2011(38.1 ± 3.48 cm) and lowest in May 2010 (24.56 ± 2.722 cm). The maximum concentration of dissolved oxygen (DO) was found in winter month December 2010 (6.83 ± 0.4735 mg/l) and the minimum in summer month May 2010 (4.00 ± 0.2378 mg/l). The BOD was highest in August (34 ± 0.122 mg/l) and lowest in January (15 ± 0.274 mg/l). The highest amount of free carbon dioxide (free CO2) was recorded as 29.67 ± 4.4514 mg/l in January 2011 and the lowest 3.81 ± 0.8972 mg/l in August 2010. Maximum amount of hardness was found in December 2010 (271.20 ± 94.6597 mg/l) and minimum in September 2010 (196.20 ± 66.3963 mg/l) with a year round average of 229.51 ± 7.82 mg/l. pH was found fair (average 7.15 ± 0.08) during the study period. Maximum pH value 7.66 ± 0.14420 was recorded in the month of August while the minimum 6.74 ± 0.0574 in the month of May 2010. Although some water quality parameters of DND canal were found to be suitable for aquaculture but it was organically polluted. Further investigation on the heavy metal pollution is necessary before using the water and crops produced from DND canal for anthropological use.Bangladesh J. Zool. 41(2): 257-264, 2013

Influence of land use/land cover on the water chemistry of Wular Lake in Kashmir Himalaya (India)

Abstract Introduction The impacts of land use/land cover (LULC) pattern on surface components of water are less well recognized, particularly in the Kashmir Himalaya. The paper highlights the relationship between LULC and water chemistry for Wular Lake in Kashmir Himalaya. Methods We used Indian Remote Sensing satellite (IRS) P6 using LISS III sensor with a spatial resolution of 23.5 m for various LULC categories. ERDAS IMAGINE 9.0 and ArcGIS 9.3 were used to generate the LULC map. Water parameters like pH and temperature were measured in the field, while parameters like dissolved oxygen, free carbon dioxide, chloride, alkalinity nitrogen and phosphorus values were determined by APHA (Standard Methods for Examination of Water and Wastewater, 1998). Results The present study provides us the information about the proportion of different land cover categories and their correlation with some limnological parameters of Wular Lake. Among the various physicochemical parameters, low dissolved oxygen (DO) was observed in the LULC class which has the highest percentage of agricultural land (47.04%; r = 0.688 P < 0.05) followed by horticultural land (19.10%; r = 0.554; P < 0.01) in its catchment. The catchment area with greater percentage of agricultural fields drains maximum fertilizers in the lake, resulting in growth of microorganisms that deplete the dissolved oxygen content in the water body. Conclusions Pearson matrix predicts that agricultural land, built up, horticultural land and wasteland seem to be the foremost factors responsible for the deterioration of the water quality of the lake. Careful planning of land use is needed to bring significant reductions in nutrient exports from agriculture through various tributaries, in order to restore and maintain water quality of the lake. If this trend of agriculturization manifestation continues unabated, it will be difficult to restore the lake water quality and to subsequently correct ecological manifestation of eutrophication through which the lake is undergoing at present.

Carbon Dioxide Sorption and Transport in Amorphous Poly(ethylene furanoate)

Transport properties of carbon dioxide in amorphous poly(ethylene furanoate) (PEF) were investigated using complementary pressure-decay sorption and permeation techniques. Detailed measurements for PEF at 35 °C indicate a significant, surprisingly large reduction in carbon dioxide permeability of 19× at 1 atm compared to poly(ethylene terephthalate) (PET), despite both an increase in free volume and carbon dioxide solubility of 1.6× for PEF vs PET. The solubility increase for PEF, which originates from greater interaction between carbon dioxide and the polar furan moiety, is offset by a substantial reduction in diffusivity of 31× compared to PET. Such diffusion reduction for PEF, which is 3× greater than the 9.7× reduction in oxygen diffusivity compared to PET, is thought to originate from a hindrance of polymer ring-flipping motions compared to PET. A possible mechanism for the surprising barrier improvement for carbon dioxide in PEF vs PET is explained herein along with a detailed comparison to oxygen and water transport.

Effects of flow rate on growth performance and welfare of juvenile turbot (Scophthalmus maximusL.) in recirculating aquaculture systems

The effects of flow rate on growth and welfare of juvenile turbot (Scophthalmus maximus L.) were investigated in the present study. Fish with same initial weight (102.5 +/- 10.6g) were subjected to four flow rates, equalling to 0.5, 1, 1.5 and 2 tank volumes per hour in twelve 392L tanks during 80days. Results showed that specific growth rate of turbots increased (0.40-0.58%day(-1)) significantly with promoted flow rate (P<0.05). Total ammonia nitrogen, nitrite nitrogen, unionized ammonia nitrogen, chemical oxygen demand, total bacteria and total vibrio in tanks were affected significantly by flow rate and accumulations were found in low rate (200Lh(-1)) (P<0.05). Free carbon dioxide increased significantly with the increased flow rate and ranged between 4.5 and 13.5mgL(-1) (P<0.05). Both superoxide dismutase activity and lysozyme activity increased significantly with flow rate (P<0.05), with ranges of 108.51-131.57UmL(-1) and 551.81-869.28U mL(-1). Serum cortisol showed reversed tendency and ranged between 7.39-19.26ngmL(-1). The principal components analysis suggested that increased flow rate promoted fish welfare. It was concluded that increased flow rate promoted the growth of juvenile turbot, possibly explained by fish welfare differences in combination of health, water quality and serum parameters.

Blue-fluorescing amber from Cenozoic lignite, eastern Sikhote-Alin, Far East Russia: Preliminary results

Blue and greenish-yellow, in addition to ordinary yellow-orange amber, has recently been found in a lignite seam in the Zerkal'nenskaya depression, Primorsky Krai, Russia. The amber is associated with abundant charcoal and fusain fragments in the host rocks. Its FTIR spectra indicate the presence of significant quantities of volatile matter, including free hydroxyl groups and carbon dioxide. Both CO2 and OH− contents are greater in the greenish-yellow and blue hard varieties, suggesting rapid heating, possibly from a wildfire, followed by rapid cooling in water as a causative agent of amber hardening and extreme polymerization. This process and the following amber deposition in the reduced environment might produce the fluorescent aromatics that have been previously suggested and confirmed by this study as the blue glow main cause.

Synthesis of high molecular weight polyglycolide in supercritical carbon dioxide

Polyglycolide (PGA) is a biodegradable polymer with multiple applications in the medical sector. Here the synthesis of high molecular weight polyglycolide by ring-opening polymerization of diglycolide is reported. For the first time stabilizer free supercritical carbon dioxide (scCO2) was used as a reaction medium. scCO2 allowed for a reduction in reaction temperature compared to conventional processes. Together with the lowering of monomer concentration and consequently reduced heat generation compared to bulk reactions thermal decomposition of the product occurring already during polymerization is strongly reduced. The reaction temperatures and pressures were varied between 120 and 150 °C and 145 to 1400 bar. Tin(II) ethyl hexanoate and 1-dodecanol were used as catalyst and initiator, respectively. The highest number average molecular weight of 31 200 g mol−1 was obtained in 5 hours from polymerization at 120 °C and 530 bar. In all cases the products were obtained as a dry white powder. Remarkably, independent of molecular weight the melting temperatures were always at (219 ± 2) °C.

Seasonal variation in toxicity of citral against Fasciola larva

Objective: To test whether the larvicidal activity of citral against Fasciola varies by season. Methods: Mortality of Fasciola larva in different month of year (2011-2012) in in vitro and in vivo condition were observed at 2 h, 4 h, 6 h and 8 h exposure of citral. Results: In vitro toxicity of citral against redia was highest in between the June to August (8 h LC50: 2.58-2.62 mg/L), whereas against cercaria 8 h LC50 was in between 3.44-2.62 mg/L. Highest in vivo toxicity against redia was noted in between June to August (8h LC50: 4.20-5.09 mg/L). The lowest toxicity was observed from November to April. The highest temperature, free carbon dioxide, and lowest pH, dissolved oxygen were observed from June to August. Conclusions: The present study conclusively shows that varying a biotic factor can significantly alter the in vitro and in vivo toxicity of citral against sporocyst redia and cercaria larva. Article history:

Monthly variation in physico-chemical properties of Kosi River in Almora district, Uttrakhand

The present investigation was carried out on the Kosi River, an important tributary of the river Ramgangafrom January 2012 to December 2012. Kosi is a spring fed river. The constituents monitored included water temperature, current velocity, pH, total dissolved solid, total solids, conductivity, dissolved oxygen, free carbon dioxide, total alkalinity and hardness. Throughout the study period, the water was found hard and a significant variation of the rest parameters were observed. The present study also revealed that the physico-chemical parameters showed a great seasonal variation and velocity of water andtotal solids were found to be highest in monsoon season that had a strong impact on other physico-chemical factors of the river.

A comparison of diurnal dynamics of water quality parameters in Nile tilapia (Oreochromis niloticus, Linnaeus, 1758) monoculture and polyculture with African sharp tooth catfish (Clarias gariepinus, Burchell, 1822) in earthen ponds

The overall performance of an aquaculture system is partly determined by its water quality parameters. Poor water quality stresses and adversely affects fish growth causing low production, profit and product quality. Diurnal dynamics of water quality parameters were investigated in Nile tilapia (Oreochromis niloticus) monoculture and polyculture with Clarias gariepinus in earthen ponds. Dissolved oxygen, temperature and pH were measured and monitored for 24 h. Water samples for nutrient analysis were collected from the middle of ponds in triplicate at about 30–35 cm below the water surface using a plastic bottle. Nitrite–nitrogen (NO2–N), nitrate–nitrogen (NO3–N), unionised ammonia (NH3–N), soluble reactive phosphorus and free carbon dioxide were analysed following standard methods and procedures. The results show that dissolved oxygen concentrations during the past midnight and pre-dawn hours were significantly lower than the levels in the morning and afternoon hours (ANOVA, F = 45.709, P < 0.05) which is dangerous to the life of the cultured fishes. The levels of unionised ammonia and temperature were higher and lower, respectively, than the acceptable levels for optimum growth of O. niloticus and C. gariepinus. Nitrite–nitrogen, nitrate–nitrogen, pH, soluble reactive phosphorus and free carbon dioxide were within the recommended limits for fish growth in aquaculture. Growth parameters, feed conversion ratio and survival rate were not significantly different between culture systems (P > 0.05). Fish yield was relatively higher in polyculture (45.74 ± 0.44 tons/ha) than monoculture (30.77 ± 0.54 tons/ha). During fish farming, optimum fish growth and hence economic benefits can be accrued by devoting some efforts on monitoring the fish pond water at regular intervals. This quality assurance process will ensure that fish farmers produce fish with maximum growth and yield without polluting pond water and the surrounding environment.

Phytoplankton dynamics and species diversity in a shallow eutrophic, natural mid-altitude lake in Himachal Pradesh (India): role of physicochemical factors

Rewalsar Lake, a mid-altitude, shallow and recreational water body located in the north-western Himalayas, Himachal Pradesh (India) was studied through monthly surveys in two consecutive years (March 2008 to February 2010). Forty-seven species belonging to seven groups of phytoplankton were identified from the lake. Microcystis aeruginosa and Synedra ulna exhibited a perennial habit. Ankistrodesmus falcatus, Chlorella vulgaris, Scenedesmus bijugatus, Chlamydomonas reinhardi, Eudorina elegans, Navicula cuspidate, Synedra ulna, Euglena acus, Euglena oxyuris, Spirulina gomontii, Oscillatoria princeps and Arthrospira khannae were abundant, and Oscillatoria limosa and Microcystis aeruginosa were highly abundant. Twenty-one important criteria were studied, for example, temperature, free carbon dioxide, biochemical oxygen demand, total alkalinity, nitrate, silicate and phosphate, which provide an idea of the portability of water for irrigation and drinking purposes as per the permissible limits given in World Health Organization, Indian Council of Medical Research and Indian Standards Institute standards. Pearson's correlation revealed a significant relationship between physicochemical parameters and different algal groups. Both plankton and chlorophyll a showed a bimodal pattern of fluctuation. High annual mean concentrations of chlorophyll a (mg L−1) were recorded as 11.44 in 2008–09, and 11.04 in 2009–10. As per the Palmer pollution index, 13 pollution-tolerant algal species with a pollution score of 37 were observed. The Central Pollution Control Board categorised the water at Rewalsar Lake as ‘D–E’.

The Behavioural and Morphometric Features of West African Manatee: Trichechus senegalensis in a Semi-Wild Environment

The behavioural and morphometric features of West Africa manatee; Trichechus senegalensis, in a semi-wild environment was study from July1st 2008 to November 30th 2008. Surface water was measured to determine the Physico-chemical parameters of the stream. Mean values of surface water temperature of 26.56 ± 1.08oC; pH, 6.47 ± 0.25; Free carbon dioxide, 8.83 ± 1.44 mg/L; total alkalinity, 10.35 ± 1.85 mg/L; Dissolved Oxygen, 7.35 ± 1.42 mg/L and Biological Oxygen Demand (BOD) 2.41 ± 0.47 mg/L were within stipulated ranged as safe for aquatic organism. Eleven Macrophytes belonging to eight families were fed to the manatee daily. The morphometric measurement showed total length 192 cm, standard length 152 cm, body weight 265 kg, fluke width 36 cm, flipper length 36 cm, head length 34 cm, girth at umbilicus 120 cm, girth at genital pore 82 cm, girth at anus 64 cm. The results indicate that the semi-wild environment provides favourable conditions for the survival of the manatee.

Seasonal Variation in the Physico-chemical Characteristics of Surface Water in EtcheRiver, Niger Delta Area of Nigeria

This study examined the seasonal variation in the physico-chemical characteristics of surface water in Etche River in Rivers State, Nigeria. The study area is a vast theatre for multiple petroleum development and cottage industries activity .Water samples were collected during the dry and wet seasons, from six sampling points, two samples along the river course. Grab (Catch) water sampling method was used in collection of water samples into PVC and Biological Oxygen Demand (BOD) bottles, during the two different seasons. The water samples were well labeled and stored at 4 O C. Water Temperature (T), pH and Electrical Conductivity (EC) were measured by mercury bulb thermometer, pH meter and Conductivity-total dissolved solids (TDS) Meter, respectively. Dissolved Oxygen (DO), Total Alkalinity (TA) and free Carbon Dioxide (CO2) were analyzed by standard methods (Eaton and Franson, 2005). Differences exist in observed physico-chemical properties of water samples collected during the two seasons. For instance, during the wet season, the level of magnesium, Calcium, and pH were 72.22(mg/l), 297.3 (mg/l)and 5.07 respectively, while values for dry season were 63.19(mg/l),260.1 (mg/l) and 6.11 respectively. Value for TDS in both seasons samples were relatively higher than the Federal Environmental Protection Agency (FEPA) stipulated limits. Copper concentration was found to be between 0.09 and 0.06 mg/l. The study revealed the disposal of industrial, commercial and domestic waste into Etche River. Recommendations, preferred include, the need to control point source and non-point source contamination of the Etche River

Aquatic insect diversity in two temple ponds of Silchar, Assam, N.E. India and their conservation values

Key-words: Aquatic insects, diversity, pond, Silchar A study was carried out on the diversity and density of aquatic insect community in the two urban temple ponds – Radhamadhav akhra pond and Mandir dighi pond of Silchar town, Assam, Northeast India. All total 22 taxa of aquatic insects were recorded, 13 taxa from Radhamadhav akhra pond and 18 taxa from Mandir dighi pond. 9 taxa were found common in both the ponds. In Radhamadhav akhra pond classical relationship of dissolved oxygen and free carbon dioxide was established with low dissolved oxygen and high free carbon dioxide concentration. Pearson correlation coefficient analysis showed that the number of taxon was highly correlated with the density of taxon in both the ponds. Canonical correspondence analysis revealed that for Radhamadhav akhra pond, eigen values were 0.784 for axis 1 and 0.630 for axis 2 while for Mandir dighi pond eigen values were 0.825 for axis 1 and 0.740 for axis 2. Taxonenvironment correlation showed that aquatic insect community and environmental variables were highly correlated in both the ponds. Shannon diversity index of Radhamadhav akhra pond was in the range of 1.5−1.7 and Mandir dighi pond was in the range of 1.9−2.0. According to the dominance status by Engelmann’s Scale, only Rhagovelia sp. was found Eudominant in Radhamadhav akhra pond. No eudominant taxon was found in Mandir dighi pond.

Preliminary cap rock integrity analysis for CO2 geological storage in saline aquifers based on geochemical tests in Shenhua CCS demonstration project, CHINA

The most important public concern about CO2 geological storage is the long term isolation performance. To prevent the stored CO2 leakage into groundwater sources or the atmosphere, the possible leakage paths, must be examined and identified. Cap rock integrity is the most important factor to evaluate the long-term CO2 isolation performance. Shenhua CCS demonstration project has several reservoir-cap rock combinations from 1300 to 2500 meters in the storage filed. The formation fluids were collected from 6 formations-- 3 storage target formations, 1 buffer formation below the caprock, 1 formation above the caprock, 1 formation closed to ground. Dissolved free carbon dioxide and bicarbonate radical(HCO -) have been test as soon as possible, then the mineralized degrees were determined by gravimetric method in 24 hours. One of the samples was acidized with nitric acid to pH=2 after filtration, then concentration of common ions were determined by ion chromatograph. CO2 solubility measured from normal pressure and temperature to formation temperature and pressure. The caprock integrity is proved good enough for CO2 geological storage based the preliminary chemistry analysis. After preliminary analysis, according to the parameters and data collected from the inject test, production test, the integrity of the caprocks between the storage layers is also good enough according to the parameters and data collected from the injection tests and production tests.

English

This research paper represents a brief analysis of physico-chemical characteristics of three different water bodies namely: earthen pond, cemented pond and lake located at Bhimtal, Nainital, Uttarakhand during winter season. Air temperature, water temperature, pH, DO, free CO2, total alkalinity, total hardness, total nitrogen, nitrite, nitrate, phosphate, ammonium and silicate were the physico-chemical parameters observed during the experimental period. The physico-chemical parameters influencing the aquatic productivity of the water bodies were found in the range of 12 to 17.5&deg;C, &nbsp;6.5 to 8.8,&nbsp; 5.7 to 8.0 mg/L,&nbsp; 0.36 to 2.7 mg/L, 38 to 63 mg/L, 0.01 to 0.23 mg/L, 0.02 to 0.15 mg/L,&nbsp; 0.4 to 4.3 mg/L,&nbsp; 0.36 to 2.38 mg/L, 0.4 to 158 mg/L,&nbsp; 31 to 46 mg/L,&nbsp; 1.0 to 2.2 mg/L for temperature, pH, dissolved oxygen, free carbon dioxide, total alkalinity, ammonia, nitrite, nitrate, phosphate, silicate, total hardness and total nitrogen, respectively. Key words: Physico-chemical, aquatic productivity, water. &nbsp;

Multi-isotope and Hydrogeochemical approach for characterizing Saturnia thermal groundwater (Grosseto, Italy)

Aim of this study is to define the groundwater flow of thermal area of Saturnia, through both chemical and isotope analyses. After a first detailed geological-geophysical survey and a quantification of the available groundwater resources, we analyzed several chemical compounds (Na, Ca, Mg, K, Chlorides, Sulfates, Nitrates, total alkalinity, Li, Sr, B, Fluorides, soluble Silica, free Carbon Dioxide, Sb, As, Se, H2S, Fe, Mn, Hg e Pb) and isotopes (2H; 3H, 3He, 4He, 13C, 18O, 86Sr, 87Sr). Excluding the uncertainties mainly related to a large repetition of measures over time, we concluded the following conclusions. Both Lithium and Boron high values and 87Sr/86Sr values highlighted that “Calcare Cavernoso” limestone geological formation constitutes the Saturnia thermal aquifer. Such samples showed both the same chemical characteristics and source area. Boron, Lithium, δ2H, δ18O and 87Sr/86Sr show the Saturnia thermal aquifer is separated by those of Pitigliano (Latera- Bolsena thermal circuit) and Bagni San Filippo (Mt. Amiata thermal circuit). 18O, 3H e δ13C measured in samples coming from Saturnia thermal spring respectively indicate that water feeding the thermal aquifer infiltrate at 350-440 m a.s.l., that they are almost 30 years old, and finally they that are isolated regarding to external infiltration. Low value of R/Ra tends to exclude the influence of Earth mantle to the geothermal anomaly of Saturnia area. The high content in Selenium indicates a possible interaction between Saturnia spring water and those coming from the Saturnia well, with volcanic fluids. However, considering also the evidence of the separation between the Saturnia groundwater flow and those of neighboring thermal fields (Bolsena and Mt. Amiata), we hypothesized that only a exchange among these volcanic complexes and the source area of thermal water points exists, but not among these complex and Saturnia aquifer.