|
|
|
|
CONTENTS
ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 5–14 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture THE LONG TERM IMPACT OF ORGANIC MATTER ON SOIL PROPERTIES, CROPS PRODUCTIVITY AND MIGRATION OF CHEMICAL ELEMENTS AND COMPOUNDS UNDER THE CONDITIONS OF DIFFERENT DRAINAGE DEEP Saulius GUŽYS*, Ramutė AKSOMAITIENĖ, Zita PETROKIENĖ Summary The paper presents summarized investigations results of long-term organic matter impact on matter migration under the conditions of different drainage deep. Investigations were carried out in 2002–2004 period in a study object of Water Management Institute of LUA in Endocalcari Endohypogleyic Cambisols (CMg-n-w-can). Incorporation of large rates of organic matter in soil has long-term effect on soil agrophysical and agrochemical properties. Under the impact of peat, soil bulk density decreases while soil total porosity, amount of water stable aggregates, amount of humus as well as total and mineral nitrogenicontained in soil increase. The mean annual productivity of agroecosystem under the conditions of organic soil was 20–22% higher to compare with the mineral soil and made up 149–152 GJ ha-1. The chemical composition of drainage water mostly depends on drainage deep. The augmentative drainage deep increase the concentration of N-NH4+, N-NO3- and SO42- in drainage water. While concentration of K+, Mg2+, HCO3- and total mineral content decreases. Peat applied in soil makes insignificant effect on chemical composition of drainage water. The leached amounts of all chemical elements and compounds directly depend on drainage deep. Keywords: concentration, drainage deep, leaching, peat, runoff, soil, yield. *contact person Dr. Saulius Gužys, senior researcher, Water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – agrochemistry, agroecology, agricultural hydrology. Address: Parko 6, LT–58102, Vilainiai, Kėdainiai district, Lithuania. Phone: +370 671 0 61 24. E-mail: s.guzys@water.omnitel.net. Dr. Ramutė Aksomaitienė, senior researcher, Water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – investigations on plant nutrient migration and balance in basins of streams and drainage systems, water protection. Zita Petrokienė, junior researcher, Water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – investigations on plant nutrient migration and balance, water protection. Received 2005 12. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 15–21 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture OPTIMIZATION OF MUNICIPAL WASTES HANDLING SYSTEM IN ŠIAULIAI TOWN Albertas STEPONAVIČIUS*, Zenonas STRUSEVIČIUS Summary During the implementation of the Directives of state strategic wastes management plan and following Local Government Regulations, Šiauliai Municipality has to create efficient and well-balanced wastes management system adapted for the transition period (2003–2006). The paper presents the analysis of functioning of wastes management system, gives the data about the quantities of municipal wastes accumulated in the territory of municipality, and specifies the accumulation rates of wastes. During the optimization of wastes management system and having introduced local fees for the wastes handling, a new scheme of system functioning was suggested. There were determined certain costs for the handling of 1 t of wastes, including the expenses on wastes collection, assortment, recycling, transportation and storage in the landfill, closure and maintenance of the landfill, also expenses on wastes collection infrastructure, administration costs, and expenses on informative and ecological education of the society. To reduce the amounts of secondary and raw material contained in domestic wastes, special mechanisms for the collection and enhanced handling of wastes were suggested. Total sum of the expenses on handling of 1 t of wastes was calculated. The enterprises were introduced with parameters determining annual amounts of accumulated wastes; considering those parameters, the tax rate for wastes handling for different companies, institutions, organizations, groups of natural persons and inhabitants was determined. Keywords: expenses, management stages, system, wastes. *contact person Dr. Albertas Steponavičius, scientific researcher, Water Treatment Laboratory, Water Management Institute of Lithuanian University of Agriculture. Research interests – investigations of wastes and manure management and effect on the environment, studies of wastewater treatment and landfill leaching. Address: Parko 6, LT–58102 Vilainiai, Kėdainiai district, Lithuania. Phone: +370 347 6 80 20, e-mail: zenonas@water.omnitel.net. Dr. Zenonas Strusevičius, senior researcher, head of Water Treatment Laboratory, Water Management Institute of Lithuanian University of Agriculture. Research interests – ecology and environmental studies, effect of wastes and manure handling on the environment, investigations wastewater transformation processes. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 22–28 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture FLUCTUATIONS IN THE CONCENTRATIONS OF MAIN ANIONS CONTAINED IN DRAINAGE WATER Valentinas ŠAULYS*, Nijolė BASTIENĖ Summary The paper analyzes the differences between concentrations of main anions (chlorides, sulphates and hydrocarbonates) contained in drainage water, and estimates the runoff in drainage systems when 0.6% of active CaO for dry soil mass was inserted in trench backfill during the draining process of sandy loam soils. The studies were performed in Kalnujai study object in 1999–2003. The study object contains three treatments of trials. In the chemical composition of drainage water HCO3– ions are prevailing. The share of their concentration in the scale of main ions reaches 67–70%. The most obvious differences between ions concentrations contained in drainage water were those between chlorine and sulphates anions. The average concentrations of those ions contained in water in drainage variants I and II with lime additives were 1.22–1.71 times lower than those measured in water of control drains. The results of dispersion analysis have shown the differences to be significant. Total runoff of anions within the study period (68.8%) depends on the amount of hydrocarbonates. Within the spectrum of main ions runoff, hydrocarbonates are prevailing in drainage systems of variants I and II with lime additives in trench backfill: here the runoff of hydrocarbonates was 8–10% higher (4285 and 4367 kg ha-1 respectively) than in drainage systems of control variant (3985 kg ha-1). There is a strong relation between those variables. Keywords: concentration, drainage water, ions runoff, main anions. *contact person Doc. dr. Valentinas Šaulys, senior researcher, Head of Exploitation Laboratory, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, investigation of the usage and maintenance of land reclamation equipment. Address: Parko 6, Vilainiai, LT–58102 Kėdainiai distr., Lithuania. Phone: +370 347 6 81 09. E-mail: valentinas@water.omnitel.net. Dr. Nijolė Bastienė, senior researcher, Exploitation Laboratory, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, researches of drainage system reliability and exploitation efficiency. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 29–37 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture THERMAL ENERGY ASPECTS OF PLANT TRANSPIRATION PROCESS Paulius KERPAUSKAS*, Povilas Algimantas SIRVYDAS Summary The main factors for prognosis and assessment of environmental effect on the plant are light, moisture and temperature. These three factors influencing conditions of productivity bare minimum existence and perishing of the plant as thermal energy factors may be expressed by the energy balance of the plant. Plant transpiration-moisture removal from the plant is not only physiological, but also thermo-physical process occuring between the plant and agro-fit environment. Transpiration is the process of plant energy and moisture exchanges with agro-fit environment. The thermal energy analysis of the transpiration process presented in the article allows to make a conclusion that it is possible to examine the processes occuring in the boundary layer of the leaf surface using the diagram h-x (enthalpy–moisture). All thermal energy processes in the boundary layer of a plant leaf are represented by the transpiration criterion expressed by the ratio of energies taking part in the transpiration and convective heat exchanges with environment. It is the main distinct characteristic of the transpiration process. The thermodynamic analysis of the transpiration process carried out opens new possibilities for the investigation and assessment of thermal technologies under various conditions in ambient medium of the plant. Keywords: evaporation, thermal energy exchanges, transpiration. *contact person Dr. habil. prof. Povilas Algimantas Sirvydas, Lithuanian University of Agriculture. Research interests – plant energetics, heat engineering. Dr. acting doc. Paulius Kerpauskas, Lithuanian University of Agriculture. Research interests – plant energetic, environment engineering. Address: Universiteto 15, LT–53361 Kaunas–Akademija, Lithuania. Phone: +370 37 75 23 17. E-mail: paulius@tech.lzuu.lt. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 38–44 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture LAND USE AS THE FACTOR REGULATING NITRATE NITROGEN LOAD IN RIVERS OF LITHUANIA Henrikas PAULIUKEVIČIUS*, Laima BERANKIENĖ Summary The paper analyzes the structural effects of land use areas (agricultural land, arable land, grasslands, forests) on annual nitrate nitrogen concentrations and runoff in basins of agricultural pollution. It also discusses the possibilities for nitrate runoff evaluation on the basis of its relation to land use areas in river basins, estimates the reliability of the relation between those factors, and analyzes the possibilities for the estimation of annual nitrate nitrogen concentrations with respect to their dependence on certain parameters of the basin. The most reliable connection was obtained between nitrate nitrogen runoff and agricultural land area as well as the area of arable land according to the exponential equation (R2 = 0.705–0.706); the relation between agricultural land area and nitrate nitrogen concentrations was less significant (R2 = 0.621–0.641). In the case of grasslands and forests, the relation is linear, however significantly weaker (R2 = 0.291–0.329). Correlation between the area of grasslands and nitrate concentrations is statistically unreliable. On the basis of the obtained polynomial regression equations, in basins of the rivers of Lithuania with agricultural non-point source pollution prevailing the changes in land use areas may determine 85% of average long term nitrate runoff and 75% of nitrate concentration fluctuations. All regression coefficients of regression equations with depending variable nitrate runoff area are statistically significant (p<0.05). When comparing nitrate runoff calculated according to the exponential multiple regression based on measurement data, the relative mean errors of 24 river basins are fluctuating within the range of 28 to 118% in different years. The values of errors depend on the abundance of water in a particular year. The highest values of errors were obtained when yearly precipitation rate was lowest during the whole study period. When testing the regression equation (i.e. the equation estimating the relation between nitrate nitrogen runoff and land use areas of the river basin) on the basis of the data of the Nevėžis tributaries (the Smilga, the Dotnuvėlė, the Liaudė, the Aluona, the Kruostas, the Alkupis) collected in 1993–1995, relative errors were obtained from 15 to 72% (the mean value 35%). A rather close relation was determined between measured and calculated data (R2 = 0.78). Keywords: agricultural land, arable land, concentration, forests, grasslands, nitrate nitrogen, runoff. *contact person Doc. dr. Henrikas Pauliukevičius, senior researcher, Water Protection Department, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, geography, hydrology. Address: Parko 6, Vilainiai, LT–58102 Kėdainiai district, Lithuania. E-mail: h.pauliukevicius@takas.lt. Dr. Laima Berankienė, senior researcher, Water Protection Department, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, hydrology, upių tarša. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 45–53 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture INVESTIGATIONS ON THE MEANS FOR THE IMPROVEMENT OF DRAINAGE FUNCTIONING Edmundas RAMOŠKA Summary Drainage functioning efficiency in heavy-textured soils much depends on drainage filtration ability and applied additional means. To improve hydraulic conductivity, different agro-melioration means and hydraulic engineering constructions are used, the effective functioning of which depends on the type of soil and functioning capacity of those means. It is essential to evaluate efficient functioning of those means in the course of time during different drainage functioning periods. The paper presents the data of the study period of 1999–2003 about the effect of carbonates and mineral backfill of drainage trenches on water regime and hydrological functioning of the drainage. The studies were carried out in mid-heavy and heavy dust loam soil situated on dust loam in common gley washout soil in Pasvalys district. As the study results have shown, having inserted lime additives and arranged filtration backfill in drainage trenches, positive effect on the runoff indices was observed in the thirteenth-seventeenth years. Intensive drainage functioning was observed in winter-spring period, when the average annual runoff was 83–86% in study variants. The runoff lasted on the average 42–57% of its yearly duration. In the field with subsurface filters arranged the runoff lasted on the average 6 days shorter. In respect of climatic conditions in the field where carbonates were inserted during the tillage process, the runoff in winter as well as in spring was on the average 21–30% higher compared to the control fields. In the field with subsurface filters arranged, the runoff was on the average 14% higher than in the field where carbonates were inserted during the tillage process. In autumn, when precipitation amount nearly corresponds to its determined rate, the runoff tends to be not very high; meanwhile, when the territory experiences 20-60% larger precipitation amounts, the runoff reaches 17–32% of total annual runoff and is observed to be higher in the fields with carbonates inserted and subsurface filters arranged. In four cases out of five the maximum runoff modules were formed during the flood period under different climatic conditions. In the control field the hydromodules reached 116–152% of the calculated rate, while in variants with carbonates inserted and subsurface filters arranged they were 138–260% of total calculated runoff. In the variants mentioned the maximum hydromodules were 1.2–1.9 times higher respectively; runoff coefficient was 10–20% higher accordingly. In the cold period of winter and spring, in the field where carbonates were inserted, soil water level was 10–13 cm lower, thus the flooding of arable soil layer was shorter. In the warm period of spring, during the year with normal moisture abundance, the average water levels were inconsecutively 6–26 cm lower. In autumn the water level formed much later, it was reaching the upper soil layer much more slowly and thus was significantly lower. Curvilinear medium and strong relation was determined between soil water levels in-between the drains and hydromodules. Keywords: carbonates, drainage runoff, filtration background, hydromodule, water levels. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 54–59 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture EVALUATION OF THE NEMUNAS LOWLAND SUMMER POLDERS ACCORDING CERTAIN ECOLOGICAL CRITERIA Algis KVARACIEJUS Summary Character of farming was transformed in the Nemunas Lowland summer polders during the first ten years after Lithuania restored its independence. Due to the free market, some production branches became unprofitable, and farming intensity decreased. A certain part of Tulkiaragė polder land was not used for agriculture. Such situation resulted in growing of scrubs, which consequently decreased the ecological value of Tulkiaragė polder. Sometimes agricultural activity is a must. Summer polders of the Nemunas Lowland are very important for the variety of habitats, rare plant habitats, abundance of breeding and migrating birds and migrating fishes from Curonian lagoon during the flood. The article analyzes the main ecological criteria regulating agricultural activity in summer polders of the Nemunas Lowland – habitat naturality of polders and their importance for fish and birds. Having made a multi-criteria analysis, summer polders were grouped into three ecological value groups. In fact, the results of multi-criteria analysis do not show the real situation due to not analysed economical, safety, law and other criteria, and show only advisory principle for farming and maintenance scenarios of polders. Keywords: ecological criteria, multi-criteria analysis, Nemunas Lowland, summer polders. Dr. Algis Kvaraciejus, lecturer of Department of Water Management, Water and Land Management Faculty, Lithuanian University of Agriculture. Research interest – ecological evaluation, restoration of destroyed landscape components. Address: Universiteto 10, Akademija, LT–53361 Kaunas district, Lithuania. Phone: +370 37 75 23 39, e-mail: algis@hidro.lzuu.lt. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 60–69 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture INVESTIGATIONS ON THE CHANGING TENDENCIES OF WATER QUALITY IN UPPER REACHES OF THE RIVER TATULA IN THE WAY OF RUNOFF NORMALIZATION Saulius KUTRA*, Laima BERANKIENĖ Summary The studies of changes and tendencies of the quality of surface water is one of the major questions of environment protection. The control of non-point source pollution and its reduction means are not able to change the level of pollution immediately; usually, a rather long period of time is needed. Such evaluation of the efficiency of water protection means is the monitoring of river water and determination of tendencies (trends). However, water quality is being affected not only by human activity, but by climatic and meteorological conditions as well, the influence of which on the analysis results may be eliminated having normalized the results of measurements. The paper includes the comparison of data analysis results obtained having applied and normalized original data. The paper analyzes the data of water quality and discharge measurements of the upper reaches of the river Tatula within the period of 1994–2004. As the study results have shown, in most cases the predicted reduction in the pollution is insignificant, i.e. the regression coefficients differ from zero in a lower level than the selected one (p = 0.05). Having applied two methods of the normalization of pollution runoff it was determined that the normalization of the pollution gives no additional information and thus there is no presumption for different conclusions. As the changing trend of ammonium nitrogen and nitrates determined by the Man-Kendal method within the last ten-year period shows, in basin with dominating agricultural activity the pollution with ammonium nitrogen is decreasing, while the load of nitrates does not change within the mentioned ten-year period. Keywords: runoff, runoff normalization, water quality, trend. *contact person Dr. Saulius Kutra, the Head of Water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, GIS, pollution modelling, application of remote sensing. Address: Parko 6, Vilainiai, LT–58102 Kėdainiai district, Lithuania. Phone: +370 347 6 82 47. E-mail: kutra@water.omnitel.net. Dr. Laima Berankienė, senior researcher, water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, hydrology, river pollution. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 70–74 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture EKSPERIMENTAL INVESTIGATIONS ON THE CHEMICAL, AGGREGATE AND GRAIN-SIZE COMPOSITION OF SPRING FLOOD SEDIMENT OF THE RIVER NEVĖŽIS Romualdas PUKŠTAS*, Saulius VAIKASAS Summary During large-scale floods, nearly all rivers transport large amounts of organic matter and silt washed from fields containing the finest particles of clay. Due to the effect of organic matter and electrostatic load of clay particles, the silt is able to form unstable aggregate substances of different size, containing various amounts of nutrients. When water is flowing into the valley and water flow is getting significantly lower, those derivatives are depositing and sticking onto the grass stems. We made the investigations on such process of river water purification during the summer flood of the Nevėžis in 2005. The results presented in the paper enable us to compare the changes in sediment and N-compounds concentrations contained in flooding water. As the study results have shown, due to intensive aggregation processes of sediments and unstable sedimentation velocity of suspended sediments, the operation of the mechanical composition of sediments does not reveal the actual dynamics of the real transportation and sedimentation processes of deposits. The studies have also evaluated the influence of inundated flora on the transportation of sediments and N, P, K compounds during the flood period. As the study results have shown, ¾ of flood sediments are retained in the Nevėžis valley, while the deposits contain 0,1% of total potassium, phosphorus and nitrogen compounds. Keywords: fractional composition, measurements, sediments, turbidity. *contact person Dr. habil. Saulius Vaikasas, senior researcher, Exploitation Laboratory, Water Management Institute of Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, hydraulic modelling and river bed processes. Dr. Romualdas Pukštas, senior researcher, Water Protection Department, Water Management Institute of Lithuanian University of Agriculture. Researc interests – soil physics, measurement devices. Address: Parko 6, Vilainiai, LT–58102 Kėdainiai district, Lithuania. Phone: +370 347 6 81 09. E-mail: rompaslt@yahoo.com. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 75–85 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture THE IMPACT OF NITROGEN AND PHOSPHORUS RUN-OFF ON RIVER POLLUTION Antanas Sigitas ŠILEIKA, Kazimieras GAIGALIS*, Aušra ŠMITIENĖ Summary The article reviews nitrogen and phosphorus load in the Nemunas River, formation of the load in the Nevėžis River, diffuse pollution sources in the Šušvė basin, reasons of fluctuation in the concentration in small river watersheds, and nitrogen and phosphorus leaching from crops and territories of animal barns. The article analyses the changes in nitrogen and phosphorous compounds load from the sources of the Nemunas in Byelorussia to its mouth within the period of 1986–2002. It is determined that pollution of the Nemunas and its tributaries with phosphorus and ammonium nitrogen decreased significantly during the transition period from the centralised economy to the market economy, but the pollution with nitrate nitrogen increases from the sources to the mouth of the Nemunas. Importance of the Nemunas River polders for the retention of nutrients is proved by the diffuse pollution model AGNPS. The Nevėžis River brings the largest amount of nitrogen and phosphorus to the Nemunas River. Analysis of the long-term data showed that point source pollution in the Nevėžis was reduced, but nitrate run-off from the territory of the basin increased several times. The load and retention of nutrients in the Šušvė River was analysed with the help of the source separation model. The article studies the reasons of nitrogen and phosphorus run-off in small rivers watersheds, nutrient leaching from crops and also the impact of manure accumulated on animal husbandry farms on water quality. Possibilities to reduce nitrogen and phosphorus leaching from soil are demonstrated with help of field trials. The analyses prove that the highest concentration of nutrients is contained in the water from the territory of animal barns but the largest nutrient load is leached from crop fields to surface water, especially from row crops and cereals. Keywords: leaching from soil, nitrogen, phosphorus, the Nemunas River, the Nevėžis River. *contact person Dr. Antanas Sigitas Šileika, Director of Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, GIS, environmental monitoring, water quality assessment. Dr. Kazimieras Gaigalis, the head of Water Resources Sector, Water Management Institute of the Lithuanian University of Agriculture. Research interests – hydrology, water flow and quality monitoring. Address: Mituvos 9, LT–50134, Kaunas, Lithuania. Phone: + 370 37 33 12 70. E-mail: gaigalis@water.omnitel.net. Aušra Šmitienė, ph.d. student, Water Management Institute of Lithuanian University of Agriculture. Research interests – water quality modelling in small agricultural watersheds. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 86–93 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture INVESTIGATIONS OF TRENCH BACKFILL LIMING EFFECT ON MAIN IONS LEACHING WITH DRAINAGE RUNOFF Valentinas ŠAULYS*, Nijolė BASTIENĖ Summary The paper analyzes the differences between concentrations of main ions (calcium, magnesium, potassium, chlorides, sulphates and hydrocarbonates) contained in drainage water, and estimates the runoff in drainage systems when 0.6% of active CaO for dry soil mass was inserted in trench backfill during the draining process of sandy loam soils. The studies were performed in Kalnujai study object in 1999–2003. The study object contains three treatments of trials: in variants I and II drainage trench backfill was mixed with lime additives; moreover, in variant II drain spacing was increased 1.5 times up to 24 m. In the chemical composition of drainage water HCO3 anti-ions are prevailing. The share of their concentration in the scale of main ions reaches 67–70%. The most obvious differences between ions concentrations contained in drainage water were those between potassium cations and chlorine and sulphates anions. The average concentrations of those ions contained in water in drainage systems of variants I and II with lime additives were 1.22–1.71 times lower than those measured in water of control drains. The results of dispersion analysis have shown the differences to be essential. During the study period, runoff of P-ions from drainage systems with lime additives inserted in trench backfill in variants I and II was 5.65 and 5.94 kg ha-1 respectively, which is 1.9 times lower than in drainage systems of control variant (9,41 kg ha-1). Total runoff of anions within the study period (68.8%) depends on the amount of hydrocarbonates; total runoff of cations (87.8%) depends on Ca and Mg ions. Within the spectrum of main ions runoff, hydrocarbonates are prevailing in drainage systems of variants I and II with lime additives in trench backfill: here the runoff of hydrocarbonates was 8-10% higher (4285 and 4367 kg ha-1 respectively) than in drainage systems of control variant (3985 kg ha-1). Equations of the dependence of main ions runoff on the drainage runoff height show a close relation of those variables. Determination coefficient between drainage runoff height and cations runoff R2 = 0.96–0.97 and between concentrations of anti-ions and main ions R2 = 0.99. Keywords: drainage, lime, main ions, trench backfill. *contact person Doc. dr. Valentinas Šaulys, senior researcher, Head of Exploitation Laboratory, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, processes of surface water seepage, water quality, water management policy. Address: Parko 6, Vilainiai, LT–58102 Kėdainiai district, Lithuania. Phone: +370 347 6 81 09. E-mail: valentinas@water.omnitel.net. Dr. Nijolė Bastienė, senior researcher, Exploitation Laboratory, Water Management Institute of the Lithuanian University of Agriculture. Research interests – environmental engineering and landscape management, researches of drainage system reliability and exploitation efficiency. Received 12 2005 ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 94–101 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture INVESTIGATIONS ON chemical compounds leaching in the soils of ACTIVE karst zone Tomas ADOMAITIS, Jonas ARBAČIAUSKAS, Jonas MAŽVILA, Vytautas MORKŪNAS, Aurelija RUDZIANSKAITĖ, Povilas ŠUKYS* Summary The study results of chemical compounds leaching into deeper soil layers in respect of different NPK rates applied are presented in the paper. The studies were carried out in spring crop fields (barley with perennial grass undercrop) in particularly susceptible to agricultural pollution karst moraine sandy light loam soils and glacial lacustrine clay. It was determined that fertilization rates have a significant effect on the leaching of N-NO3- and Cl-; the effect on K+ leaching is less significant. In lysimeter water (40 cm deep) of moraine sandy loam soils with more intensive fertilization the concentrations of N-NO3-, K+ and Cl- increase 3.3, 1.2 and 12.7 times respectively, in glacial lacustrine soils the concentrations of the elements increase 2.5, 1.2 and 1.8 times respectively. No significant dependence of phosphorus and sulphates leaching on the fertilization rates was observed; the leaching more depends on the amounts of phosphorus and humus naturally contained in the soil. More obvious increase in chemical compounds concentration contained in lysimeter water was observed when the fertilization rates were N60P60K60 in sandy light loams and N90P90K90 in glacial lacustrine clay soils. Keywords: chemical elements, fertilizers, leaching, lysimeter water, soil. *contact person Dr. Tomas Adomaitis, senior researcher, Agrochemical Research Department, Agrochemical Research Center, Lithuanian Institute of Agriculture. Research interests – investigations of the pollution of soil and vegetation with chemical compounds. Dr. Jonas Arbačiauskas, senior researcher, Agrochemical Research Department, Agrochemical Research Center, Lithuanian Institute of Agriculture. Research interests – investigations of soil properties, fertilization efficiency and pollution. Dr. Jonas Mažvila, the head of Agrochemical Research Department, Agrochemical Research Center, Lithuanian Institute of Agriculture. Research interests – investigations of soil properties, fertilization efficiency and pollution. Dr. Vytautas Morkūnas, deputy director, Water Management Institute of Lithuanian University of Agriculture. Research interests – agricultural and environmental engineering, land draining. Dr. Aurelija Rudzianskaitė, senior researcher, Geofiltration Research Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – environmental engineering, relations between the regime and pollution of surface and subsurface water. Dr. Povilas Šukys, the head of Geofiltration Research Department, Water Management Institute of Lithuanian University of Agriculture. Research interests – environmental engineering, relations between the regime and pollution of surface and subsurface water. Address: Parko 6, Vilainiai LT–58102, Kėdainiai district, Lithuania. Phone: +370 687 7 47 85. E-mail: lygis@water.omnitel.net. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 102–111 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture THE EFFECT OF APPLIED ORGANIC AND MINERAL FERTILIZERS ON NUTRIENT LEACHING Stefanija MISEVIČIENĖ Summary On the basis of the results of field experiments carried out within the period of 1999–2003, the paper analyzes the effect of slurry and mineral fertilizers on the agrochemical properties of light-textured soils and nutrient leaching. As the studies have shown, the effect of slurry (variant I) as well as that of mineral fertilizers (variant II) on the fertility of soil, nutrient leaching and productivity of crops is very similar. The application of slurry as well as mineral fertilizers results in increased amounts of nutrients contained in the soil; while the plant residuals inserted into the soil result in higher amount of humus. Due to rapid plant uptake, the applied slurry ensures 3.4% higher yield of grown crops compared to mineral fertilizers. Therefore leached N and P amounts are 1.9% and 12.5% higher in the latter variant. K leaching was 36.6% more intensive in the variant where slurry was applied. This was due to 7.5% higher total amount of potassium input into the soil. P and K concentrations contained in drainage water of both variants did not exceed the maximum allowable concentration (MAC). N concentrations exceeded MAC in both variants when annual crops were grown or clover was ploughed up. Keywords: agrochemical properties of the soil, mineral fertilizers, NPK leaching, slurry. Dr. Stefanija Misevičienė, scientific researcher, Water Treatment Laboratory, Water Management Institute of Lithuanian University of Agriculture. Research interests – ecology and environmental management, effect of manure handling on the environment, investigations of pollutants transformation processes. Address: Parko 6, Vilainiai, LT–5048 Kėdainiai district, Lithuania. Phone: +370 347 6 80 20, el.p. s.miseviciene@takas.lt. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 112–117 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture INVESTIGATIONS ON THE SUBSURFACE (RAINFALL) WASTEWATER IN THE TERRITORY OF SUGAR FACTORY Simanas AŠKINIS Summary During the monitoring of subsurface water, some difficulties related to the determination of discharges of subsurface runoff may occur. The problem is that it is rather complicated to collect wastewater from a large territory into one collector, and it is quite expensive to arrange measurement posts in separate basins of runoff as it needs the processing of large amounts of data. Calculation methods are precise enough and besides much simpler. Having applied the methods mentioned, the subsurface runoff of the territory of Kėdainiai Sugar Plant was differentiated in respect of separate basins. There were 10 basins of subsurface runoff distinguished, quantitative analysis of the formation of their subsurface runoff was made, also soils, surface covers and slopes of separate territories were estimated. Four basins with concentrated production were selected, where the pollution of subsurface water is most intensive. Having determined the area of those basins and distributed them according to their surface cover, the subsurface runoff was calculated in respect of the curves of precipitation amount and its dependence. Regression equations for the calculation of pollution input into the stream Šerkšnė from those basins were created. Keywords: rainfall duration, rainfall intensity, subsurface runoff, surface cover, water pollution. Dr. Simanas Aškinis, senior scientific researcher of Water treatment laboratory at the Lithuanian Institute of Water Management. Research interests – ecology and environmental engineering, the impact of the management and usage of slurry and wastewater on the environment, researches on the transformational processes of pollutants. Address: Parko 6, Vilainiai LT–58102, Kėdainiai district, Lithuania. Phone: +370 347 6 80 20. E-mail: s.askinis@takas.lt. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 118–123 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture Investigation on Oxygen Mass Transfer of Nitrifying Submerged Fixed Bed Biofilter Viktoras Mongirdas*, Albinas Kusta Summary Airlift fed nitrifying biofilter applied for recirculating aquaculture system in terms of oxygen transfer coefficient was investigated in this study. Oxygen tansfer coefficient was determined using chemical oxygen depletion and biofilter vessel reaeration method. The data was fitted using non-linear regression method. The dependence of oxygen transfer coeficient on biofilter bed filling level was studied in 4 cases, airlift flow rate was determined in 4 cases, airlift submergence ratio was calculated in 2 cases. Bed filling level significantly affected oxygen transfer coefficient only at higher rates (75%) of filling. This was due to high void space of packing material. The airlift flow rate has direct positive correlation with oxygen transfer expressed by a power function and in the case of lower submergence rate surface aeration starts to affecting oxygen transfer significantly, resulting in higher values of the oxygen transfer coefficient. Keywords: aeration, airliftoxygen mass transfer, fixed-film. *contact person Viktoras Mongirdas, doctorate student, Lithuanian university of agriculture, Hydrotechnics department. Research interests – aerobic biofilm treatment technologies, recirculating aquaculture systems Address: LT-53361 Universiteto 10, Akademija. Kaunas district, Lithuania. Phone: +370 37 75 23 93. E-mail: aduta.vm@is.lt. Habil. dr. Albinas Kusta, Lithuanian university of agriculture, Hydrotechnics department professor, doctor habilite. Research interests – hydroengineering. Received 12 2005 ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 124–127 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture GENETIC TYPES OF ISLES IN LITHUANIAN RIVERS Aldona BAUBINIENĖ Summary Fluvial processes in Lithuania have been extensively investigated for a long time already. However, the information about the genetic diversity of the isles in Lithuanian rivers is still very scarce. The author of this article was trying to supplement the scientific classification of the isles in Lithuanian rivers with more detailed genetic aspects. The work is based on the data collected during individual experimental studies and on the previous cartographic analysis of the distribution of isles in rivers. The paper also presents an overview of the classification of isles in rivers of other countries. According to the formation conditions, the main genetic units of the isles of Lithuanian rivers may be grouped into natural and technogenic. The natural conditions include physical – geographical conditions and structural changes of river flows. The diversity of natural river isles is greater. The influence of hydrodynamic (river) factors generates three genetic types of river isles. Most Lithuanian river isles are accumulative. In certain types of relief (when deep depressions in the ground are parallel to river channels) after very high flood or long-lasting tectonic movements of the earth crust the water flows may encircle higher areas of flood plains forming socle isles. When changes of erosive basis occur and rivers cut their way into deeper layers of lithosphere, the sediments accumulating on higher surfaces generate genetically mixed natural isles. Accumulative isles can be grouped into flood plain isles and channel isles according to their position in the river channel. Most Lithuanian rivers are distinct for channel isles. The majority of channel accumulative isles are formed as a result of sediment accumulation in shallow areas. The flood plain isles and channel isles are divided into two subtypes each. The genetic diversity of socle isles is poor. The existence of their sub-types in the Lithuanian rivers has not been proved yet. There are two kinds of mixed natural river isles in Lithuania: some of them are formed when alluvial deposits cover the shallow areas of riverbed, the others occur when alluvial formations adjoin the socle isles. Technogenic isles are man-made isles. According to the formation characteristics, four types of technogenic isles can be distinguished in Lithuania. Keywords: river bed processes, river isles. Aldona Baubinienė, junior researcher, Department of Climate and Water Systems, Institute of Geology and Geography. Research interests – recent fluvial processes, river islands. Address: Ševčenkos 13, L–03223 Vilnius, Lithuania. Phone: +370 5 2 10 46 97; fax: +370 5 2 10 46 95. E-mail: baubiniene@geo.lt. Received 12 2005. ISSN 1392–2335 Water Management Engineering, 28(48)1, 2005, 128–132 © Lithuanian University of Agriculture © Water Management Institute of Lithuanian University of Agriculture ISSUES OF RURAL ENVIRONMENT PROTECTION Zenonas KAUNAS Summary In Lithuania, rural environment protection means are supported from EU structural funds and prepared according to the State Rural Development Program. However, no expected improvement in the issues of environment has been observed. The objective of the research was to evaluate present rural environment protection policy, determine its possible correction trends and suggest the means for the enhancement of environment protection. Therefore the legal acts determining EU and Lithuanian rural environment protection policy have been analyzed, and the newest scientific recommendations have been evaluated. As the analysis results have shown, the single management of farmer-polluter does not give necessary effect. The pollution of water flowing from fields exceeds the maximum allowable concentrations several times. Pollutants are to be retained in natural or artificial biological filters. Therefore drained lands located in valleys and sinkholes of the relief should be re-naturalized, or artificial wetlands should be arranged. The most rational solution of the arrangement of wetlands is to prepare the projects of renovation of drainage systems. In conformity with the Laws of the Republic of Lithuania, the arrangement of artificial wetlands and creation of rational land use areas are to be solved as the problem of rural territorial development. In Lithuania, this might be done having made the land consolidation projects. The initiation and elaboration of land consolidation projects should be considered as one of the fields of rural community. In such way one of the main aims of rural development could be implemented, i. e. conditions of the quality of environment would be improved and the management of landscape would be enhanced. Those attitudes of rural environment protection policy are suggested to be included into rural development plan of 2007–2013. Keywords: land consolidation, land and water resources management, pollution of water bodies, rural development, wetlands. Dr. Zenonas Kaunas, associate professor, Department of Hydrology and Climatology, Vilnius University. Research interests – land and water management. Address: Čiurlionio 21/27, LT–20009 Vilnius, Lithuania. E-mail: zenonas.kaunas@gf.vu.lt. Received 12 2005. |
|