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Ground water regime and pollution in the vicinity of karst sinkholes
2007
Sauliene, A., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst. | Sukys, P., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.
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.
Afficher plus [+] Moins [-]Ecological and economical aspects of the management of drainage systems in Lithuania
2007
Saulys, V., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst. | Bastiene, N., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.
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.
Afficher plus [+] Moins [-]Growth regression models problems of the experimental data estimation in engineering application
2007
Arhipovs, S., Latvia Univ. of Agriculture, Jelgava (Latvia)
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).
Afficher plus [+] Moins [-]Active class - work forms versus student passivity
2007
Augustaitiene, I., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania)
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.
Afficher plus [+] Moins [-]The model of students' patriotic attitude development during the study course 'Rural tourism'
2007
Dunska, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Luse, N., Latvia Univ. of Agriculture, Jelgava (Latvia)
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.
Afficher plus [+] Moins [-]Fungicide application effect on yield and quality formation of winter oil-seed rape (Brassica napus L.)
2007
Balodis, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia) | Bankina, B., Latvia Univ. of Agriculture, Jelgava (Latvia) | Vitola, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
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.
Afficher plus [+] Moins [-]Spring barley yield, grain quality and factors affecting them
2007
Braziene, Z., Lithuanian Inst. of Agriculture, Rumokai, Vilkaviskio reg. (Lithuania). Rumokai Research Station | Kaunas, J., Lithuanian Inst. of Agriculture, Rumokai, Vilkaviskio reg. (Lithuania). Rumokai Research Station
Effects of nitrogen fertilizers and weather conditions on spring barley (Hordeum vulgare L.) yield and grain quality were investigated at the Rumokai Experimental Station of the Lithuanian Institute of Agriculture in the period of 1998-2000 and 2003-2004. The soil of the experimental site was Hapli Epihypogleyic Luvisol. Analyses were made with fertilisers rates of 0 and 90 kg haE-1. The data of analyses indicated a positive and reliable correlation between the yield of spring barley and the amount of precipitation in May (rate of correlation was 0.70**) and a negative and reliable correlation with the amount of precipitation in June and July (rates of correlation were -0.80** and -0.29* respectively). A reliable though weak correlation was found between the application of nitrogen fertilisers and the yield of grains. The amount of precipitation in April and the spring barley leaf diseases had a considerable negative effect on 1000 grain weight and grain size. Strong correlation was identified between the amount of precipitation in May and June and the protein content in grain. Nitrogen fertilisers promoted protein accumulation in grain.
Afficher plus [+] Moins [-]The evaluation of effectiveness of Rhizobium leguminosarum in field beans (Vicia faba)
2007
Ansevica, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dubova, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
The vegetation pot experiment was conducted at the Institute of Soil and Plant Sciences of the Faculty of Agriculture of the Latvia University of Agriculture. The aim of the experiment was to investigate the effectiveness of five Rhizobium legumonosarum strains stored in the period from the 18th of August till the 20th of October 2006 in the collection of the Latvia University of Agriculture. Three of the five mentioned Rhizobium legumonosarum strains were included in the international Rhizobium database IBP World Catalogue of Rhizobium collections. Taking into consideration the results of the experiment it has been pointed out that all Rhizobium strains were active and inoculated plants formed nodules on the roots. Inoculation with Rhizobium strains increased the proportion between shoots and roots' weight. It has been found that the dry matter content of the inoculated plants increased in comparison with the untreated ones. In addition, negative correlation between the dry matter and the protein content has been observed.
Afficher plus [+] Moins [-]Variability of wild martagonlily (Lilium martagon L.) in the region of Kurzeme, [Latvia]
2007
Balode, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this research is to evaluate the variability of the martagonlily (Lilium martagon L.) found in the wild in the west of Latvia. Latvia is situated in a nature zone between the vegetation of Northern and Central Europe. The country distinguishes itself with a large variety of flora and fauna (total approx. 27, 7 thousand species). The genus Lilium L. includes approximately a hundred species, subspecies and varieties of species. In northern Europe, one of the best known and longest cultivated of lilies is L. martagon L. It is distributed across the largest growing area of most species - from western Portugal throughout Europe and Asia. To evaluate the survival potential of L. Martagon L. in Latvia, research was carried out in locations at Kurzeme - districts of Ventspils, Kuldiga, and Tukums. The results indicate that the diversity in genotypes varies according to location and distribution. There are differences in phenotypes and colour variability from pale to bright violet-pink. Diameter of flower varies between of 3.5 to 6.0 cm. The height of these plants varies up to 114 - 130 cm. The flowering time is in June and July. Wild martagonlily found in these regions is growing in calcareous soils among shrubs in river valleys and semi-shaded deciduous forests. This particular martagonlily is hardy and disease resistant and is recommended as a donor in breeding programs.
Afficher plus [+] Moins [-]The influence of organic acids and phytogenic additive on pigs performance
2007
Jansons, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Nudiens, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
A study was conducted to determine efficiency of an organic acids and phytogenic additives on pigs' growth processes and digestive tract microflora. The feed of the control group (C) did not contain the additives. The feed of the organic acid group (A) contained 6 kg of organic acids additive per tonne feed for pigs after weaning, 4 kg per tonne feed for grower pigs, and 3 kg per tonne feed for finished pigs. The feed of the phytogenic additive group (F) contained 0.5% of phytogenic additive per tonne feed for pigs after weaning, and 0.2% per tonne feed for grower and finished pigs. The feed of organic acids plus phytogenic additives group (A+F) contained 6 kg of organic acids additive per tonne feed for pigs after weaning, 4 kg per tonne feed for grower pigs, and 3 kg per tonne feed for finished pigs 0.5% of phytogenic additive per tonne feed for pigs after weaning, and 0.2% per tonne feed for grower and finished pigs. Compared to groups pigs from the group (F) had by 9.7%, group (A+F) - by 8.3 % and from group (A) had by 3.2% higher mass. The bests results of feed conversion were found in the group (A+F) - 2.84 kg, which was by 8.5% less than in the group (C), whereas the group (F) had by 5.1% and group (A) - by 6.7% better results than the control group. The results of Duodenum and Rectum microflora analyses showed that use of organic acid and phytogenic additives reduced mould yeast Staphylococcus sp. colony formed units (CFU gE-1).
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