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Definitions of the Boussinesq limit problem of the non-stationary theory of filtration, formulated for a scalar porous medium, to the Blasius problem, and then to the limit problem of smaller parameters, are made. The research subject is the hydrodynamic processes occurring during surface irrigation and in the upper layers of the soil cover aeration zone and the parameters of water consumption of crops against a natural background on a lysimeter. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) landfill cover, having several advantages over the conventional cover is now being widely used for landfill closure. Effectiveness of an ET cover depends on site-specific factors such as climate, soil hydraulic properties and vegetation. The variation of soil saturation and matric suction due to the fluctuation in the environmental parameters, mostly precipitation and temperature may affect the performance of an ET cover. The objective of the current research is to inspect the soil saturation and suction variation in an ET cover site due to actual climatic condition and simulate these results through numerical modeling. In this study, one lysimeter was randomly chosen from six lysimeters that were constructed in the City of Denton landfill, Texas. Moisture content and matric suction were measured by sensors installed in the lysimeter at different depths from the top surface (0.31m and 0.762m). Unsaturated behavior of the soil or soil water characteristics curve (SWCC) was determined in the laboratory. Finite Element (FE) model PLAXIS 2D was used to numerically simulate the water movement through unsaturated soil. Based on the input soil and climatic parameters, the change in matric suction and saturation was investigated in the model and compared with the field instrumentation data. The generated model could reproduce the relative fluctuation in suction and saturation with the varying precipitation, and the average variation was found to be 48% and 6.71% respectively in the shallower depth. The study revealed that FE modeling can provide a practical indication of the soil hydraulic behavior of ET cover system. [ABSTRACT FROM AUTHOR]

Enhanced forest growth may respond to the increasing demand for wood resources. Moreover, the forest is considered to be carbon storage, thus contributing to climate change mitigation. The forest soil fertilization, as well as forest drainage, thinning and regeneration may be an effective measure in increasing harvest rates. In the context of bio-economy, wood ash needs to be managed and can be utilized as an equivalent to potassium and phosphorus containing fertilizer. Ammonium nitrate can be used as fertilizer in forests on mineral soil since nitrogen is considered to be a tree growth limiting element in boreal forests. However, environmental aspects like leaching of the fertilizer should be taken into account. The aim of this research is to evaluate the impact of wood ash, ammonium nitrate and combined wood ash and nitrogen fertilizer impact on the chemical properties of soil water in dominated forest site types in Latvia. The trials were conducted in total in 16 forest stands. The fertilizers were spread in treatment plots, but the control plots were left untreated. The soil water samples were collected for two seasons. The pH, potassium, calcium, magnesium, phosphate and total nitrogen were determined in the soil water samples. Ammonium nitrate had an impact on the elevated concentration of total nitrogen in all experimental objects; although the significant differences between the control plot and treated plot were detected only in a part of experimental objects. The elevated concentrations of total nitrogen decreased after two months and remained above the control level. Interestingly, we observed a trend of both - increased and decreased concentrations of potassium, calcium, magnesium and phosphate. Nevertheless, only a part of the differences was statistically significant. The impact of wood ash on chemical properties of soil water was less pronounced in comparison to ammonium nitrate. [ABSTRACT FROM AUTHOR]

Waste and the landfills have been accompanying man for centuries. Although modern technologies limit the impact of landfills on the environment, the landfills where waste materials used to be buried still have an impact on the environment. The studies into the waste itself are performed on small samples, mainly with static leaching tests. These are quick and relatively cheap methods. However, conducting leaching tests on small samples may result in failing to detect some leached substances. Lysimeter studies, due to their duration and the size of the sample, produce much more reliable results and thus the possibility of a more precise assessment of the threat to the aquatic environment posed by the examined waste. Lysimeter experiments are undertaken relatively rarely as they are time-consuming and expensive. The aim of this paper is presentation of currently conducted lysimeter studies on municipal landfill waste in various scientific centers. Lysimeter tests on municipal waste is one of the most difficult because of the composition of the wastes. Only a few scientific units in the world have decided to undertake lysimeter studies on municipal waste. Lysimeter studies on waste of this kind were performed among others in Turkey, Italy, Germany, Japan, India, Thailand and in two scientific centers in Poland. These tests are performed on different sizes of waste samples (25-390 liters) they are designed to determine different parameters and can last from several months to even several years. The paper also presents the preliminary results obtained within the lysimeter experiment, which was carried out by the authors at the municipal waste landfill in Tychy Urbanowice (southern Poland). [ABSTRACT FROM AUTHOR]

Metallurgical wastes are deposited in landfills or are being recycled, mainly as material used for engineering work. They are also sources of pollution in the groundwater environment. For this reason, it is necessary to explore environmentally safe ways of using them. Environmental impact assessments of waste can be made on the basis of static or dynamic laboratory tests. The alternative is to carry out lysimetric research. However, this kind of research is rarely performed due to the degree of complexity, cost and duration. This paper presents the preliminary results of a 12-year lysimetric research project concerning the metallurgical waste deposited at the landfill site Lipowka in Strzemieszyce Małe, Southern Poland. The research investigated the quantity and chemical composition of the leachates and rainwater. Measurements were conducted in 2005, 2008/2009, 2014/2015 and 2016/2017. The preliminary results confirm the significant negative impact of leachates from the Lipówka landfill site on groundwater quality in its vicinity. This risk is caused mainly by leaching from as sulfates, potassium, chlorides and nitrogen compounds. Mn, Ba, Sr, As, Hg, Sb, B were also found in the initial phase of the study. After 20 years of experiment, the leaching of the examined substances decreased up to 20 times. [ABSTRACT FROM AUTHOR]

In Brazil, the municipal solid waste (MSW) disposal currently considered appropriate from an economic point of view, is still the landfill. Nonetheless, this disposal is restricted to the state capitals and major urban centers such as the city of Campinas, whose population is slightly more than 1 million, ranking it as the 14th most populous Brazilian city. Several researches have been developed in order to understand the geomechanical behavior of MSW confined in the municipal sanitary landfill, Delta A. One of them refers to the study of the biodegradation of the wastes confined in six large lysimeters. These lysimeters were built with the same dimensions and were filled with about 2.3 tonnes of MSW, previously selected and characterized. The filling and compaction of the MSW were performed using a rammer. The wastes were confined within six lysimeters under two conditions, three of them received the application of sodium chloride solution in order to slow down the process of biodegradation, and the other three did not receive the application of the solution, simulating the operating conditions of Delta A Sanitary Landfill. This research specifically describes the compaction procedure used, so that the unit weight design was reached, and analyzes the key factors that interfered in this procedure. The main difficulties encountered during filling and compaction of waste within these lysimeters are described as well as the key factors, such as moisture content and gravimetric composition of the wastes, which influenced the compaction, are presented. [ABSTRACT FROM AUTHOR]

This work is focused on the use of soil water samplers (lysimeters) by ex-situ study of the mobilization of contaminants (heavy metals) in technosols of Zemianske Kostoľany area. This area is the most polluted area in Slovakia, where in 1965 a dam failure of a coal ash impoundment released cca. 3 million m3 of power plant fly ash with a high content of arsenic and other potentially toxic trace elements in the surrounding environment. Under the new morphogenetic classification system we call the soil with a layer of power plant ash as technosol. The total content of arsenic (AsTOT) in the studies samples is in the range of 109.65-1334.37 ppm. Mobility of arsenic in the anthropogenic materials was studied by sampling of pore waters using soil lysimeters (Prenart Equipment ApS, DK).The collected soil samples without homogenization and sieving (better simulation of natural conditions) were placed in experimental containers in which there were installed soil lysimeters. The aim of ex-situ experiments was to assess the mobility of toxic elements from solid samples using the selected leaching solutions (glucose+SAB medium, 1 mM citric acid, simulated acid rainwater) and compare their efficiency. From the results obtained we can find that the strongest extractant was the solution of glucose + SAB (Sabouraud) medium - which increases the activity of soil microflora - that producing organic acids play an important role in the environmental fate of contaminants in soils. Preliminary results (two 5-day cycles) obtained from leaching experiments confirmed that the stimulation of soil microorganisms (biostimulation) was the most effective method and the result represents the basis for innovative methods for soil remediation in Zemianske Kostoľany area. That method wasn't sufficiently effective for the mobilization of other contaminants (Pb, Cd, Zn) - the results were insignificant. [ABSTRACT FROM AUTHOR]

Mapping high spatial-temporal resolution evapotranspiration (ET) over large areas is important for water resources planning, precision irrigation and monitoring water use efficiency. However, both the traditional field measurement and aerodynamic estimation mainly focus on obtaining local ET. Remote sensing data often can be used to retrieve large area instantaneous ET at low spatial resolution over region or global scale. Therefore, using traditional measurements and high resolution image data to generate high spatial-temporal resolution ET is becoming an important research direction. In this paper, the complementary relationship model (CR) was employed together with meteorological data to estimate actual ET, and the results were validated by lysimeter observation. Furthermore, CR model was combined with high resolution image, IKONOS data, to estimate instantaneous field scale ET and they also were transferred into daily ET. The cumulative evapotranspiration (ET) of winter wheat during the reproductive phase from March to June of 2011 was 469.12 mm, essentially corresponding to the annual precipitation in the Beijing area. The most high accuracy of estimated ET by CR model is also on May(R2=0.863, RMSE=0.103 mm). The transferred daily ET by self-preservation of evaporative fraction(EF) method were consistent with lysimeter measurements for all four months(R2=0.937, RMSE=0.668 mm). It was proved in this study that CR model can be used to estimate precision field scale ET with meteorological data and high resolution remote sensing data together in a region with limited ground data availability. [ABSTRACT FROM PUBLISHER]