Highly polluted wastewater is formed on private farms. The wastewater contains Ntotal and Ptotal concentrations up to 150 mg lE-1 and 30 mg lE-1 respectively, which is 2-3 times higher than that contained in domestic wastewater. During the biological treatment of wastewater the removal of organic pollutants (BOD5- biochemical oxygen demand, and SS - suspended solids) is about 96% and the treatment efficiency satisfies the environment protection standards. However, the removal of biogenic pollutants is only 55%, thus the residual pollution with biogenic substances exceeds the maximum allowable rate according to Ntotal and Ptotal for wastewater released into the environment. Currently, different natural and artificial powdery mineral materials (zeolite, filtralite, etc.) containing metals and carbon compounds are transported into Lithuania. Such materials could be used as Ntotal and Ptotal adsorbing filters. In respect of the filter load with pollutants, biologically pre-treated wastewater treatment efficiency of Ntotal and Ptotal was determined to be from 50 to 91% and from 49 to 90% respectively. Having filtrated to the wastewater through a filter containing 50% of zeolite and 50% of filtralite, Ntotal and Ptotal removal efficiency was fluctuating from 28 to 60% and from 23 to 70% respectively. Having made the investigations with different loads of minerals, it was determined that N removal is more efficient in the zeolite mineral filter, while P removal is more efficient in the filtralite filter. In order to reach the best results of biogenic pollution removal, both mineral mixtures should be used for the load of the filter.

The objective of the present studies has been to estimate peculiarities of nitrogen removal in constructed wetlands of different construction. In limited companies (LTD) 'Pastoge' and 'Nikola', constructed wetlands of vertical flow (VFCW) are arranged, while limited company (LTD) 'Agaras' has two-stage constructed wetlands of horizontal flow (HFCW). In all the objects the supplied wastewater is after primary treatment. Having compared the efficiency of ammonium and nitrite nitrogen removal in two types of constructed wetlands (VFCW and HFCW) it was determined that larger amounts of total nitrogen are removed in HFCW (38.1%) rather than in VFCW (24.4%). However, in VFCW smaller amounts of ammonium and nitrite nitrogen are discharged with wastewater. No significant effect of the fluctuations of ambient temperature on the removal of ammonium and nitrite nitrogen was observed in HFCW (difference in average values of cold and warm periods was 3-8%). A rather reliable relation (R2 = 0:738) was determined between ammonium nitrogen concentrations in wastewater outflow and HFCW load according to total nitrogen, however, ammonium nitrogen amounts in treated wastewater (when filter load according to total nitrogen is 0.3 to 4.6 g mE-2 dE-1) exceeded the maximum allowable concentration (MAC) and were fluctuating from 6 to 32 mg lE-1.

The objective of the present studies has been to estimate wastewater treatment efficiency of surface-flow wetlands for finishing treatment of secondary effluent. The studies have been carried out within the reconstructed wastewater treatment facilities in Babenai (Kedainiai district, Lithuania), where, after the initial wastewater treatment in the septic tanks and biological ponds, a plant filter has been set for finishing the wastewater treatment. The removal efficiency of the main pollutants in the filter like BOD5, suspended solids, total N (nitrogen), and total P (phosphorus) has become the focus of the analysis as well. Wastewater treatment efficiency analysis was done on base measurements taken in all seasons of the year within the period 2003-2006. Surface-flow wetlands are characterised by good removal efficiency of the organic pollutants. At the average load of the examined plant filter - 0.9 mg O2 lE-1 BOD5 (biochemical oxygen demand), the removal efficiency reached up to 61.2%. Low winter temperatures reduce the rate of removal for BOD and the biological reactions responsible for nitrification and denitrification. During the warm period of the year, the treatment efficiency of BOD5 was 70.8%, and during the cold one - 52.4%. However, the total N constituted up to 16.7% and 9.7% respectively. Due to the anoxic and anaerobic conditions in the filter, wastewater after the treatment on average contains 66.0% of ammonium nitrogen of the total N concentration. After a year, with the growth of plants the phosphorus removal efficiency improved and at the average load of the examined plant filter according to P 0.063 g mE-2 dE-1, on average 0.018 g mE-2 dE-1 of the total P was removed, i.e., the removal efficiency constituted 28.6%.

The most urgent environmental problem in cultivated land areas of Lithuanian karst region is the protection of subsurface water from technogenic pollution. In terms of subsurface water pollution, the ambience of sinkholes is considered to be particularly dangerous. The work was carried out in 2004-2006 in the district of Birzai. Having analyzed the regime of sinkhole water formed in the vicinity of sinkholes as well as the regime of ground water of their vicinity it was determined that this regime is different in respect of the local hydrogeological conditions. A common regularity was observed: during the snow thaw period and rainy period sinkholes are fed with water from ambient soil and with shallow ground water, during the dry period water accumulated in peat of the failures of sinkholes flows into the ambience, and during the particularly dry periods subsurface water abates in sinkholes and they start draining the ground water very intensively. Analyzing the interrelations of water quality indices it was determined that in most cases the quality of ground water in sinkholes and in their vicinity is closely related. Sinkholes with water level higher than the ground water level and with higher chemical compounds concentrations make no adverse effect on ground water quality due to comparatively low runoff into the environment. However, such sinkholes are considered to be potential pollution sources of lower aquatic layers. Nitrate nitrogen is one of the most harmful pollutants getting into the sinkholes from agricultural fields and farming land plots where mineral fertilizers are applied. Ground water of higher level polluted with the nitrogen is obviously polluting the subsurface water of the sinkhole as well.

After the private ownership of land was restored and a part of land reclamation structures was given to land owners, the intensity of land use has changed. In the areas of Lithuania, which are less favoured for agriculture, the land is not intensely used. Further financing of land reclamation of such areas from the state budget grants is economically inefficient as the return of relatively high investments is very low. With the changing of land reclamation infrastructure it is necessary to prepare measures which would facilitate rational, regional agricultural specialization corresponding to natural conditions. The routine procedure of financing the land reclamation has to be changed as well. The paper analyses the changes in usage of drained land areas and financing of the land reclamation sector in Lithuania during the last decade (1997-2007). The purpose of this research is to establish the criteria of the economical efficiency of drainage systems and to propose methods how to change the financing of state-owned land reclamation infrastructure. On the grounds of the carried out situation analysis, a methodology of distributing state grants for land reclamation to municipality budgets are presented. To have an efficient use of the state budget funds, the operation and maintenance of shared land reclamation systems have to be carried out according to the maintenance plans approved by municipalities, which would provide for arrangements and compensations due to conflict of interests arising when land plots are used in different ways. Possible ecological measures that could be applied when carrying out repair and reconstruction of drainage systems are discussed.

If among engineering phenomena exist nonlinear interconnections, they are expressed with help of corresponding nonlinear functions. Teaching the regression analysis for the engineering science students one of the important topic is method of Least Square Method (LSM) and their application in the nonlinear regression analysis. Based on experience at Latvia University of Agriculture, the illustrated approach of teaching of nonlinear regression topics for undergraduate students in engineering applications is presented. Teaching statistics on regression analysis, students usually have problems with interpretation of the transformed regression model parameters significance. The tasks of teaching using LSM in the nonlinear regression analysis are discussed. On the figure 1 regression dependence are shown between such sizes as age of pine-tree and his height. The main species in Latvia is pine-tree (47% from total Latvia forest area); growth of trees motion is stipulated by tips of growth circumstances (Statistical Yearbook of Latvia, 2005).

Recently, the graduates should not only be technically competent, but also they should be skilled in communication and team work, have social and global awareness, be self directed and prepared for life-long learning. Knowing of languages contributes to student personal development. However, passivity of the students in the English classroom is among the factors limiting not only active engagement in academic tasks, acquisition of communicative skills but also soft skills needed for future profession. Therefore, at Lithuanian University of Agriculture, where student-active teaching and learning has been applied the study of the most acceptable class work forms for breaking passivity and improving students' motivation in the classroom for learning English as a foreign language was performed. The most persistent problem for the passive students who are afraid of speaking is the inability to find right words to express themselves (31%), and the fear of making mistakes, criticism, and sounding foolish (almost 55%). The application of the active class-work forms seems to behave well over fighting the passivity and enabling acquisition of the most important skills both for foreign language acquisition and becoming perspective future employees. Team work in created by a teacher relaxed atmosphere in the fitted classroom was found to be one the ways for breaking silence and passivity of the students in the English class room.

The migration of many rural youngsters to bigger cities and other countries in order to find a place for better life and job is not only economic but also educational and up-bringing problem nowadays. The development of the Latvian countryside is closely connected with the investment of educated young people in the long-term creative development of the native country. Latvia University of Agriculture students consider that one of the reasons of leaving their native land rather easily is because they were not purposefully brought up in the field of the patriotism and the feelings of belonging to their native country. Higher educational establishments apply different study models dependent mainly on the aims of educational institutions. The aim of this work is to develop a study model of 'Rural tourisms' taking into account that the study course 'Rural Tourism' has its up-bringing potential which can help to increase the development of students' patriotic attitude during the acquisition of Latvian cultural and historic inheritance. The priority of the study course 'Rural Tourism' in Latvian higher educational establishments is supposed to contribute to the development of students' entrepreneurial skills but this direction does not increase the development of students' patriotism. The above mentioned developed study model is based mainly on the dynamics of the relationship between the study program and the development of students' patriotism.

peer reviewed | Perionyx excavatus, cultured in Vietnam in early 1990s, showed an important role in managing organic wastes and supplying a very nutritious feed for animals. To develop vermiculture in practice, four treatments of different substrates including 100% fresh cattle manure (CM); cattle manure + pig manure in 50:50 ratio (CPM); cattle manure + pig manure + rice straw in 50:40:10 ratio (CPMRS) and pig manure + rice straw in 90:10 ratio (PMRS) were prepared to examine worms’ growth and their decomposition efficiency. All substrates were composted 45 days before feeding to worms. The result showed that cattle manure (CM) was the best substrate for worm growth (biomass gained 713 g after 45 days or 242.6% of growth rate). The worm biomass achieved in CPMRS and PMRS treatments was significantly lower than that in CM treatment. As compared to primary substrates, vermicomposts exhibited an excellent result with a great increase in the amount of total P (0.3 – 0.6%), total K (0.09 – 0.23%), Ca (0.51 – 0.79%) and a decrease in N-NH3 and N-NH4+. A study was carried out to evaluate the influence of feed supplemented with worms on the growth and meat quality of broiler chickens (n=148). Starting at 4 weeks old the chickens were divided into a control group and three experimental groups corresponding to worm levels in the diet of 1, 1.5 and 2% on a dry matter basis according to a completely randomized design. Chicken fed the diet supplemented with 2% worms had the highest live weight at 10 weeks (1925 g/head vs 1823 g/head for the control). Percentage of breast and leg meat was also higher than in the control group. Chickens in the three worm groups had better FCR. The different levels of red worm supplementation did not affect meat quality (pH, color, and the rate of dehydration after storage and processing).

Sowing area under oil-seed rape (Brassica napus L.) has grown dramatically only during the last 10 years in Latvia. Lack of knowledge and research on different issues is observed. The aim of our research, started on season 2005/2006 in Research and Study farm Vecauce, was to investigate the influence of split fungicide (1st dose of fungicide Juventus 90 s.c. (Metconasol 90 g LE-1) used as growth regulator in autumn at the 4-6 leaf stage and the 2nd dose at the growth stage 63-64) application. Winter rape development in autumn, winterhardiness, disease incidence, and yield and its structure elements were estimated. Totally 13 cultivars were used in the trial, but several assessments were done for 5 cultivars. Additional objective was to evaluate economic effect of fungicide use. Winter rape biometrical indices were influenced by the fungicide application in autumn period and by used cultivar. Fungicide treatment in autumn increased also the rape winterhardiness. Our research for the first time indicated that Phoma stem canker could become a problem for rape growers in Latvia. Fungicide use (in growth stage 63-64) decreased incidence of this disease a little (on average by 5%). Fungicide treatment according to applied scheme increased the average seed yield (check 5.37 t haE-1, with fungicide 5.80 t haE-1; LSD0:05 = 0:18 t haE-1), but impact on yield structure elements was mainly non-essential. Despite agronomic improvements, economic calculation showed that on average fungicide use in 2006 was not pro table. Research should be continued for specification of conclusions.