Volume 14 - 2012

Treatment of young landfill leachate, collected from municipal solid waste site of city of Konya, was
investigated by using the Fenton process. The leachate itself showed the characteristics of pH 7.25,
COD 38.2 g L-1 and BOD5 22 g L-1. Ratio of BOD5 to COD with 0.58 indicates that leachate can be
defined young. Fenton oxidation of landfill leachate was expressed in two-stage process, where a
fast initial reaction (H2O2/Fe2+) was followed by a much slower one (H2O2/Fe3+). Overall kinetics can
be described by a second-order rate equation followed by zero-order one. The kinetic studies were
undertaken at the different temperatures and reaction rates increcesed by increasing temperature.
The apparent kinetic constants at 303 K are k = 3.16 x10-3 L g-1 min-1 and k0 = 0,171 g L-1 min-1,
respectively. Fenton reagents effectively degraded the leachate organics and most of the
degradation was completed within 30 minutes for all temperatures. The performance of Fenton
process was not only presented as a COD removal but also expressed as the amount of generated
sludge and its properties. Sludge properties were revealed with Capillary Suction Time (CST) and
Sludge Volume Index (SVI). The minimum CST value was obtained at the optimum molar ratio of
4.12 mol/mol and increasing temperature resulted in a positive effect on CST values. All SVI values
were significantly low which indicates that sludge itself had good settling properties.

A considerable number of diseases are directly related to environmental impact. Toxic metals such
as Hg, Pb, Cd, and As may damage significantly the human health when they exceed certain levels
in the body. For example specific precautions should be taken for the diet of pregnant women and
the children. Lead concentrations exceeding the safe values can cause severe damage to the
development of central nervous system, as well as a general developmental delay of fetuses and
young children, interfering with the functioning of almost every brain neurotransmitter. In particular
for the pregnant women, it has been found that the exposure of the fetus on high lead values may
cause, apart from neurological and behavioral problems, low birth weight, pre-term delivery,
spontaneous abortion and stillbirth. Organic mercury (methyl mercury) is the most dangerous form of
mercury, because it is the most easily absorbed orally and crosses into the brain and fetus so
readily. Populations exposed to chemical compounds containing As, Ni, Cr, Cd, etc. are considered
of high-risk in developing cancer.
Environmental geochemical studies can help in assessing the quality of the environment as well as
the determination of the sources of pollutants, their behaviour and other characteristics. This
knowledge is necessary in any application of remediation methodologies and waste management for
the prevention of pollutants in getting into the food chain. It is also used in determining safe criteria
regarding the quality of soils, drinking water, construction of schools, playgrounds etc. In this work
the importance of environmental geochemical research and its applications towards the protection of
human health is demonstrated.

A noticeable decline of Quercus ithaburensis ssp. Macrolepis, a typical mediterranean species, has
been recorded in the past few decades throughout Greece. The triggers were mostly human
influences and specifically illegal cuttings, wildfires, and overgrazing. Regeneration and future
management of this species is therefore questionable. To investigate the effect of companion plants
on this decline as expressed by water availability and plant growth, a pot experiment was conducted
and oak seedlings were planted with Bromus sterilis and a mixture of Trifolium repens and T.
fragiferum as companion plants. Midday water potential from May to September and oak growth at
the end of the experiment were measured as factors affecting oak physiology. The results suggest a
different effect on the water potential of the oak seedlings depending on the companion plant
species and the time of the year. The presence of a companion plant that has completed its life cycle
by the end of spring may positively influence the water status of oaks during the summer months
due to shading and lower soil water evaporation. On the contrary, when the companion plants
continue their life cycle in the summer, the negative effect may be continued, specifically during the
very dry months. The negative effect of grass on the growth of oaks may be attributed to their
shading from the dense grass biomass. It can be concluded that control of competitive vegetation,
especially of grasses, is crucial for Quercus ithaburensis ssp. macrolepis regeneration by natural
(from acorns) or artificial (with up to one-year-old seedlings) methods. This control is necessary at
least in the first year after establishment, when seedling height is less than that of the competitive
vegetation. If the latter can not be removed by some ways (e.g. controlled grazing), then it is safer to
use taller oak seedlings of an older age in the reforestation projects.

When flushing carry out as pressure condition, a scour cone is performed around the outlet. As the
flow around the outlet in the pressure flushing is three dimensional, therefore that it is difficult to
establish a general empirical model to provide accurate estimation for scour cone volume and
length. In this study artificial neural network (ANN) with multi-layer perception which using backpropagation
algorithm (MLP/BP) was used. The scour cone volume (Vf) and length (Lf) were
modeled as a function of three variables; water depth (HW), mean flow velocity through outlet (uf)
and mean grain diameter (D50). For training and testing model, experimental data in two forms of
original and non-dimensional are selected. The results of this research indicate that MLP/BP model
can predict the scour cone volume and length. Finally, sensitivity analysis with original and nondimensional
data set show that mean flow velocity through outlet (uf) and uf / √(g (Gs-1)D50) have a
greater influence on scour cone volume and length rather than other parameters.