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The objective of this study was to determine whether the use of the co-regionalization of the distanceto-
river topographic variable with the soil properties topsoil clay and sand can improve their mapping.
The interpolation techniques: ordinary kriging, kriging combined with regression (two models) and
heterotopic co-kriging were applied to data from 153 observation points. The two models of kriging
combined with regression involve: (a) linear regression of the two soil variables with the distance-toriver
variable on the 153 observation points followed by kriging and (b) summation of the kriged regression
values and kriged regression residuals. For co-kriging 350 additional observations for the distanceto-
river-variable were employed. The distance-to-river data were easily obtained from the map of the
area which was stored in a Geographical Information System (GIS). The performances of the methods
were evaluated and compared using the cross-validation method. The mean error of prediction indicates
reasonably small bias of prediction for the two soil variables by almost all the methods. The mean
square error showed that heterotopic co-kriging produced better estimates of the soil variables than
kriging but there was a clear advantage in using the first model of kriging combined with linear regression
technique. The second model of kriging combined with regression does not show any particular
advantage over the other methods.

The ability of activated carbon and different low-cost by-products and waste material as sorbents to remove
various reactive dyes from aqueous solutions and wastewaters was investigated. All aqueous dye solutions
contained 2,000 mg l-1 NaCl, to mimic real dye wastewater. Batch kinetic and isotherm experiments were
conducted to determine the sorption-desorption behavior of the examined dyes from aqueous solutions
and wastewaters by different sorbents, including activated carbon, fly ash, bentonite and bleaching earth.
The results from the aqueous solutions indicate that the form of the isotherm equation is not necessarily
unique for best description of both sorption and desorption data. The values of the isotherm
parameters are not the same, indicating a significant hysteresis effect.
Of the 9 sorption systems tested, 5 are best described by the Freundlich, 3 by the Langmuir and 1 by
the linear sorption model. Of the 7 desorption systems tested, 5 are best described by the Freundlich
and 2 by the linear model. In all cases, the sorption capacity for dye removal was higher for activated
carbon, followed by fly-ash and then by bentonite.

Life cycle assessment (LCA) is a technique for holistic environmental assessments of products and
processes. The unique feature of this methodology is its focus on the entire life cycle of a product, from
raw material extraction to final disposition. In order to assess the role of LCA in environmental management,
a comprehensive overview of its theoretical background (including recent aspects of its principles
and framework) is presented in this paper. From this overview it is obvious that, in spite of its drawbacks,
LCA is recognized as a valuable methodology in environmental management, capable of analysing and
assessing in a scientifical way the environmental consequences of various products and activities.
Complementary to this analysis, a life cycle inventory (LCI) case study from the Greek market is also presented.
In this LCI application, all the methodological issues and guidelines are taken into consideration
in order to calculate the resource requirements and the environmental loadings of ten alternative packaging
products while some of them are presented by each life cycle stage. The results of this LCI case
study cover a long list of inflows and outflows. Notwithstanding that these results are difficult to interpret,
they are very detailed and not affected by uncertainties introduced by impact assessment.

In this work the covariability of sea surface and lower troposphere temperatures (SST-AT) is investigated for
winter (DJFM) and summer (JJAS), over the whole northern hemisphere, by utilizing monthly anomalies in
grid boxes for a 22-year period. Air temperature variations in the lower troposphere are examined in terms
of 1000-500 hPa thickness. At first, factor analysis (FA) is applied on both sets of data in order to reduce their
dimensionality and to group objectively grid points with a similar long term temperature variability. Also, FA
revealed numerous teleconnections in both fields, most important being those governed by PNA in the
Pacific Ocean and NAO in the Atlantic Ocean. Then, by using the FA results as a guide, correlation coefficients
between the mean temperature time series of the subareas defined by FA in the two fields are estimated.
The highest values, up to r=0.70, were found for subareas located one over/under the other. Finally,
by introducing time lags, an attempt of forecasting either SST form AT or AT from SST is made. Although
in some cases the coefficients appear increasing, test showed that the increase is not statistically significant.
In any case, it appears that, on monthly time scale, it is the AT that controls SST and not the vice versa.