The last few decades we have witnessed an enormous rise in awareness of the importance of
wetlands. Mathura beel1 has been assumed to take the attention in recent years because of its
ecological significance in terms of flood control, water purification, aquatic productivity, and microclimatic
regulation etc. The aim of this paper is to present a complete scenario of Mathura beel
through different analyses. To materialize the main objective, the water quality monitoring, socioeconomic
analyses, and a perception study on wetland use and wetland threat are considered
separately. In this study, the objective was extended to observe the complete socio-economic status,
and a detailed perceptional study on wetland use, and wetland threat. At the end of the study,
detailed management options have been given to protect and to conserve the economy and the ecosystem
of Mathura beel.
Water volume consumed for crop irrigation at the plain of Thessaloniki – northern Greece, was
estimated and compared against the volume reported by the General Land Reclamation
Organisation (G.L.R.O.) of Thessaloniki – Lagada. For the estimation of net crop water
requirements, apart from crop evapotanspiration, the contribution of effective precipitation, soil
moisture and the phreatic aquifer through capillary elevation were considered. Estimates were
performed for five collective pressurized irrigation networks (P. Skilitsi, Nisi, Alexandria, Shinas,
Kariotissa), located at the plain of Thessaloniki and referred to years 1995 to 2004 inclusive. River
Aliakmonas is the main source of these networks. Results reveal considerable losses of irrigation
water that are related to the management, operation and maintenance of the networks by the Local
Land Reclamation Organizations (L.L.R.O.).
Detailed meteorological data required for the equation of FAO-56 Penman-Monteith (P-M) method
that was adopted by Food and Agriculture Organization (FAO) as a standard method in estimating
reference evapotranspiration (ETo) are not often available, especially in developing countries. The
Hargreaves equation (HG) has been successfully used in some locations to estimate ETo where
sufficient data were not available to use the P-M method. This paper investigates the potential of two
Artificial Neural Network (ANN) architectures, the multilayer perceptron architecture, in which a backpropagation
algorithm (BPANN) is used, and the cascade correlation architecture (CCANN), in which
Kalman’s learning rule is embedded in modeling the daily ETo with minimal meteorological data. An
overview of the features of ANNs and traditional methods such as P-M and HG is presented, and the
advantages and limitations of each method are discussed. Daily meteorological data from three
automatic weather stations located in Greece were used to optimize and test the different models.
The exponent value of the HG equation was locally optimized, and an adjusted HGadj equation was
used. The comparisons were based on error statistical techniques using P-M daily ETo values as
reference. According to the results obtained, it was found that taking into account only the mean,
maximum and minimum air temperatures, the selected ANN models markedly improved the daily
ETo estimates and provided unbiased predictions and systematically better accuracy compared with
the HGadj equation. The results also show that the CCANN model performed better than the
BPANN model at all stations.
A methodology for landslide susceptibility assessment to delineate landslide prone areas is
presented using factor analysis and fuzzy membership functions and Geographic Information
Systems (GIS). A landslide inventory of 51 landslides was created in the mountainous part of Xanthi
prefecture (North Greece) and the associated conditioning factors were determined for each
landslide by field work. Six conditioning factors were evaluated: slope angle, slope aspect, land use,
geology, distance to faults and topographical elevation. Fuzzy membership functions were defined
for each factor using the landslide frequency data. Factor analysis provided weights (i.e., importance
for landslide occurrences) for each one of the above conditioning factors, indicating the most
important factors as geology and slope angle. An overlay and index method was adopted to produce
the landslide susceptibility map. In this map 96% of the observed landslides are located in very high
and high susceptibility zones, indicating a suitable approach for landslide susceptibility mapping.
Chlorine was accepted as an effective disinfectant for drinking water in early 1900s. Because of
chlorination, chlorine has dramatically reduced the incidence of waterborne diseases. An unwanted side
effect is the formation of harmful by-products upon chlorination. The most significant group of disinfection
by-products formed during chlorination is the trihalomethanes (THMs).
In this reason, European Union initiated the maximum contaminant level (MCL) of total concentration of
THMs to 100 μg L-1. Because of this regulation, operational parameters of the WTP and raw water quality
characteristics need to be studied in depth in order for THMs to be minimised. Statistical analysis is
necessary for this purpose employing the parametric two-way ANOVA for the concentrations of chloroform
(CHCl3) and dichlorobromomethane (CHCl2Br) and the analysis of variance on data ranks of
chlorodibromomethane (CHClBr2) concentration. Chlorine dose, postchlorination, bromide levels, reaction
temperature, reaction duration and dissolved organic carbon levels as well as pH of raw water, are the
factors that affect the rate of THMs formation and the total THMs yield. Athens Water Supply and
Sewerage Company (EYDAP SA), as the water supplier of a city with 3.5 million inhabitants, makes
continuous attempts to improve water quality.
Trihalomethanes are a major class of chlorination by-products in drinking water. They are formed
when chlorine reacts with bromide (Br-) and natural organic matter (NOM) in source waters.
Toxicology studies have shown all THMs to be carcinogenic or to cause adverse reproductive or
developmental effects in laboratory animals. THMs are small volatile molecules, which are
hydrophobic, non biodegradable and adsorbable on granular activated carbon (GAC).
The objective of this pilot study is to evaluate the adsorption capacity for individual THMs of a GAC
filter-adsorber (A) and a GAC postfilter-adsorber (B), both fed with chlorinated natural water.
For this purpose, a GAC pilot plant was operated as a filter-adsorber and a postfilter-adsorber in
Galatsi WTP, Athens (GTP) until the removal of individual THMs by GAC was eliminated
(breakthrough). Regular sampling was performed during operation and the parameters measured
were: THMs, DOC, free residual chlorine, bromide, turbidity, pH and temperature.
From the experimental data, GAC bed life, GAC usage rate, GAC loading and operation time to
breakthrough were calculated for most THMs. TBM was almost not detected. Some desorption of
THMs, especially TCM and BDCM, was noticed during the operation of both adsorbers.
Near breakthrough for THMs, equilibrium between adsorbed and dissolved THMs was considered to
have been established. The GAC equilibrium loading of individual THMs was assumed to depend on
the mean value of their influent concentration, which was not constant. By correlating the equilibrium
data by linear regression to conform to the Freundlich isotherm, the Freundlich constants 1/n and k
were determined for each of THMs. They are related to the physicochemical characteristics and
background organics of water and the specific GAC used. The strength of the adsorption bond and
the GAC capacity was higher for DBCM, lower for BDCM and even lower for TCM for both
adsorbers. In addition, the GAC(B) capacity for BDCM and DBCM was higher than that of GAC(A),
probably due to larger surface area and surface chemistry of GAC(B). Also, the lower particle size
and the higher uniformity coefficient of GAC(B), along with the lower flow rate may have attributed to
that by enhancing GAC equilibration. However, TCM was less adsorbed by GAC(B), probably due
to the stronger competition effect by BDCM and DBCM, being in much higher mean influent
The DOC content of influent water seems also to reduce significantly the adsorption of THMs
(especially of TCM), as the comparison of our results with the isotherm results with distilleddeionized
water by other researchers showed.
Laboratory-scale experiments were performed in order to examine the effect of microwave field on
the effectiveness of KPEG method (nucleophilic substitution of the chlorine atoms in a molecule of
PCBs by alkaline polyethylene glycol PEG) in the removal of PCBs from highly contaminated mineral
oils with the content of indicator congeners (No 28,52,101,53,138 and 180) above 5500 mg kg-1.
Results show that the microwave field significantly increases the reaction rate and the method’s
effectiveness in the removal of chlorine from the molecules of PCBs. Addition of a small amount of
an ionic liquid, in this case 1-butyl-3-methylimidazolium hexafluorophosphate–[bmim][PF6],
significantly positively affects the results obtained under the influence of microwave field. The KPEG
method enhanced by the application of microwaves could be used in practice for decontamination
and recycling of PCB-containing dielectric fluids in electric capacitors and transformers. High
efficiencies of the reaction were achieved even when microwaves were applied with no PEG added,
only by the presence of alkaline hydroxide or by the presence of a small amount, up to ca. 2%, of an
ionic liquid [bmim][PF6]. The microwave enhanced KPEG method might has some advantages for
practical uses in decontamination applications.
Globalization and liberalization polices of the government of India have increased the number of
road vehicles nearly 92.6% from 1980-81 to 2003-2004. Therefore to know whether there is effect of
increase of industrialization in the urban areas like Pune (18° 32′N, 73° 51′E); Mumbai (18° 55' N,
72° 54' E) and at rural station like Ramanandnagar (17° 4′ N, 74° 25′ E); pollution index is measured.
Pollution index which is ratio of average positive to negative small air ion ratio is plotted for week
days and week end. At the rural station like Ramanandnagar Monday to Saturday are working days,
while Sunday is holiday. It is observed that ratio of average positive to negative small ion ratio is
maximum for all time periods during the week day as compared to week end. The data have been
collected during the period from first 1 June 2007 to 31 May 2008; the period under analysis involves
8,040 hours shows that the peak of the positive to negative small air ion ratio is observed in winter,
and dip is observed in post-monsoon season. As Ramanandnagar is surrounded by vegetation area,
therefore due to plant transpiration of Radon and Thoron small air ion maximum are observed at
noon time rather than night time. During the week end positive small air ion count is low as
compared to week days. While during week end negative small air ion count is very high as
compared to week days, which is observed in all the seasons. Post-monsoon is the transition period
during which few thunder storms are observed. Due to these thunder storms additional amount
negative ion are introduced and positively charged aerosols are cleared from the atmosphere.
Therefore in the post-monsoon negative small air ion count is high as compared to all other seasons.
Such type of diurnal variation of small air ion detected at rural station Ramanandnagar has never
been observed elsewhere.
Application of material balance analysis (in one of our previous studies) to natural gas flare in the
upstream petroleum operations confirmed the emission of primary air pollutants in form of CO, CO2,
NO, and NO2 from “sweet” natural gas while “sour” gas emits SO2 in addition; incomplete
combustion may be an impetus for the release of volatile organic compounds (VOCs) into the
atmosphere from this same source. In this article, the significance of these gaseous emissions in the
formation of secondary air pollutants in the atmosphere is reviewed for the purpose of air pollution
control strategy. The goal is to describe the formation mechanism, to determine the influencing
factors in formation along with environmental impacts and to identify the required technological and
policy control approach for an improved environmental protection.
The removal of dyes from colored effluents, particularly from textile industries, is one of the major
environmental concerns these days. Current methods for removing dyes from wastewaters are
costly and cannot effectively be used to treat wide range of such wastewaters. This work describes
the use of grounded rice hull as adsorbent material. Aqueous solutions of various methylene blue
dye concentrations (5-25 mg l-1) were shaken with certain amount of adsorbents to determine the
adsorption capacity. Both treated and untreated rice hulls were used for methylene blue adsorption.
The effects of adsorbents dose, initial pH, initial dye concentration and contact time on dye removal
have been studied. Maximum dye was sequestered from the solution within 60-90 min after the
beginning of every experiment. The adsorption capacity increased from 72 to 94 % with increasing
the pH from 3 to 10. Pretreatment of rice hulls with citric acid did not reveal any beneficial effect.
Rice hulls were more effective compared to commercial used adsorbents used. The results showed
that ground rice hulls can be considered as potential adsorbents for methylene blue removal from
dilute aqueous solutions.