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An assessment of a Scotch pine (Pinus sylvestris L.) plantation in the high mountain forest region in Artvin, Turkey
2005
Olmez, Z.(Kafkas University (Turkey))E-mail:zaferolmez@yahoo.com | Yahyaoglu, Z.(Kafkas University (Turkey))
Turkey is a mountainous country with many high mountains. Recent estimations show that there are approximately 20.7 million ha of forested area in Turkey, covering 25.8% of the total land area. However, little over half of this forested area is classified as unproductive (51.7%). Artvin is located in the North Eastern Black Sea part of Turkey and is the home of a very rich biological diversity. Forests in Artvin region are in different climatic zones - from temperate climate to continental climate zone - and there are several vegetation zones in the region which ranges from sea level to the altitude of 3500 m. A Scotch pine (Pinus sylvestris L.) plantation, planted in 1996 in the alpine zone in Artvin-Ardanuc region, was investigated. The size of study area was 40 ha and this research was done on 12 sample plots. There were 50 Scotch pine seedlings on each sample plot. Height and root collar diameter of the seedlings were measured. The mean slope was the same (60%) on the sample plots, and the effects of exposure and altitude significantly affected the height and root collar diameter growth of the seedlings (P is less than 0.05). It was determined that increased altitude is associated with decreased height growth and root collar diameter of the seedlings.
Mostrar más [+] Menos [-]Elements of distance education and e-studies content in higher educational establishments
2005
Reihmane, S.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:kaiva@cs.llu.lv
Nowadays the industrial society changes over to the information society. The introduction of elements from distance education and e-studies is an effective means in updating traditional education system in higher educational establishments of Latvia. Due to the decrease of the amount of contact classes and increase of the share of independent work, the version of studies of a mixed-mode type (the introduction of separate elements from the distance education and e-studies in traditional subjects of studies) is the most appropriate types of education in higher educational establishments of Latvia. Hence new study materials elaborated exactly to cover the needs of independent active studies with feedback are required. The techniques type of study materials has to be acceptable for students of different age groups. The aims and tasks are to be clearly defined in the study materials for distance education and e-studies. Tests and examinations are carried out to state whether the aims and tasks are fulfilled. The objective of tests and exams is not a severe evaluation of student knowledge but the analysis of made mistakes. With the introduction the elements of distance education and e-studies in the process of teaching and learning of subjects in higher educational establishments, the students from towns and country will have greater possibilities to acquire knowledge at the speed, time and place most suitable for them.
Mostrar más [+] Menos [-]The effect of harrowing on the weediness and yield of spring barley in organic farming
2005
Svarta, A.(Latvia Univ. of Agriculture, Skriveri, Aizkraukle reg. (Latvia). Agency Research Institute of Agriculture)E-mail:svarta@inbox.lv
Field trials were carried out on organic farming fields at the Research Institute of Agriculture of the Latvia University of Agriculture (LLU). The influence of harrowing (without harrowing, before emergence, at the stage of tillering, before emergence and at the stage of tillering) depending of pre-crop (red clover, winter rye for grain, bare fallow and green manure) and use of stable manure (60 t haE-1 or without) on the weediness and yield of spring barley 'Sencis' was tested during 2003-2004. In spring barley, 18 species of weeds were established at the stage of earing during 2003-2004. The most widespread of perennial weeds were Elytrigia repens (L.) Nevski and Sonchus arvense L. The dominant annual weeds were Chenopodium album L., Stellaria media L., Capsella bursa-pastoris L., Polygonum spp., and Matricaria inodorum L. The number of annual weeds at the stage of earing differed during the years 50-160 (in 2003) and 33-118 (in 2004) annual weeds per mE-2. The influence of harrowing on the number of annual weeds was different during the testing years. The influence of harrowing on the grain yield was negligible during 2003 and 2004.
Mostrar más [+] Menos [-]The effect of nitrogen and sulphur fertilization on tiller formation and grain yield of spring wheat
2005
Siaudinis, G.(Lithuanian Inst. of Agriculture, Akademija, Kedainio reg. (Lithuania))E-mail:sgintaras@lzi.lt | Lazauskas, S.(Lithuanian Inst. of Agriculture, Akademija, Kedainio reg. (Lithuania))E-mail:sigislaz@lzi.lt
In 2003 and 2004, field experiments with spring wheat (Triticum aestivum L.) were carried out at the Lithuanian Institute of Agriculture in Dotnuva, Lithuania. The aim of the study was to evaluate the effect of nitrogen and sulphur fertilizers on tiller formation and grain yield of spring wheat (variety 'Munk'). N and S fertilizers were applied at 3 rates: N (0, 60 and 120 kg haE-1) and S (0, 15 and 30 kgE-1 ha). Both years, N fertilization had a significant effect on tiller formation. At harvest, the total number of tillers was approximately 0.5 tillers higher in the plots with the application of N120. The growing season in 2003 was comparatively dryer, and a significant increase in grain yield was found - up to 60 kg haE-1 of N. Due to higher rainfall in 2004, grain yield was much higher and the highest effect was found with the maximum N supply - 120 kg haE-1. One thousand grain weight was influenced by the year, while fertilizers did not have any significant effect. The impact of S fertilization on the number of tillers and final grain yield was insignificant; nevertheless S fertilization increased the concentration of S in the aboveground plant mass.
Mostrar más [+] Menos [-]The development of aquaculture in Turkey
2005
Canyurt, M.A.(Ege University (Turkey))E-mail:canyurt@sufak.ege.edu.tr
Turkey has rich inland water sources, about 200 natural lakes, about 750 artificial lakes or ponds, about 193 reservoirs, 33 rivers and streams of 177,714 km length and 8333 km of coastal strips. Some lagoons covering of 70,000 ha in Aegean and Mediterranean coastal strips are very suitable for aquaculture. The main fish species cultured in Turkey are carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar), gilthead sea bream (Sparus aurata), European sea bass (Dicentrarchus labrax), bluefin tuna (Thunnus thynnus), Blackl sea turbot (Pselta maxima), Mediterranean mussel (Mytilus galloprovincialis) and shrimp (Penaeidae spp). Aquaculture production of Turkey has grown steadily over the years from 5,782 t in 1990 to 63,000 t in 1999 and to 79,031 t in 2000. There are 1309 farms in inland water producing approximately 32,466 t of fresh water fish species and 352 farms at sea producing 40,119 t of sea fish species, mainly Gilthead sea bream and European sea bass.
Mostrar más [+] Menos [-]Internal stresses of biomass compositions
2005
Nulle, I.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:Imants.Nulle@llu.lv | Kakitis, A.(Latvia Univ. of Agriculture, Jelgava (Latvia))
Relevant resources for biomass energy production are cereal straw residues and emergent vegetation from wetlands. This bulk herbaceous biomass is a material with low density. Density of briquetted straw and reed has been increased from 60 kg mE-3 to 1000 kg mE-3. The storage, dosage and mixing of biomass bulk materials before compacting are necessary, which requires working knowledge of the bulk properties of materials. The angle of repose of straw, reed and peat particles was investigated. It was stated that angle of repose of straw and reed varies between 45-55 degrees. The angle of repose of peat particles varies between 37-50 degrees. The stress ratio between horizontal and vertical stress is important for equipment design. This ratio was investigated for different size particles of straw, reed and peat. Stress ratio of straw particles varies between ~ 0.6-0.71.
Mostrar más [+] Menos [-]Accumulation of sludge during the treatment of wastewater from milk processing companies and its application as a soil fertilizer
2005
Steponavicius, A.(Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.)E-mail:AlbertasStepanavicius@one.lt
The processing of milk in dairy companies produces a certain amount of wastewater and liquid wastes. During the treatment process of such wastes sludge is accumulated in treatment facilities. The sludge is a rather valuable soil fertilizer; however, apart from plant available nutrients, it also contains large amounts of pollutants. The paper analyzes the quality of wastewater treatment process performed in treatment facilities of dairy companies, and specifies the amounts of plant available nutrients contained in sludge accumulated during the treatment process of wastewater and liquid wastes. The amounts of heavy metals contained in sludge are compared with their maximum allowable concentrations determined in the environmental requirements for soil fertilization (Aplinkosaugos reikalavimai..., 2001). On the basis of the study results and normative documents of environment protection, the article presents optimal rates and regime for sludge fertilization as well as analyzes the agro-technical and qualitative characteristics of sludge spreaders made at the Water management Institute of Lithuanian University of Agriculture and used during the technological process of fertilization.
Mostrar más [+] Menos [-]The modelling of regional economical management of land reclamation works
2005
Saulys, V.(Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.)E-mail:valentinas@water.omnitel.net | Bastiene, N.(Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.)
According to EU Water Framework Directive, anew model of land reclamation management and financing will be developed. Taking into consideration the high vale of state investment required to ensure a steady work of land reclamation systems, it is important to reject the funds allocated on an equality principles and to give preference to the regions where the maintenance, rehabilitation and repair of these structures is more effective. The discussion concerning the allocation of state funds is elaborated in this paper. On the basis of statistical analysis, natural and economical regional differences were evaluated. Four scenarios of the allocation of special subsidies from state budget are submitted for approval. When modelling the financing results based on the regional distribution methodology, the changes in base financing indices are under discussion.
Mostrar más [+] Menos [-]Investigation and evaluation of the state of protective belts and inflow of erosion products into drainage channels
2005
Ragauskas, S.(Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.)E-mail:valentines@water.omnitel.net
As the result of the studies on the condition of protective belts of drainage channels (PB) have shown, due to improving maintained and mechanical damaged protective belts large amounts of erosion products contained in surface water inflows the channel bed. Disorderly condition of protective belts does not correspond to the requirements of environment protection. Mechanical damages are often related to unsustainable human activity in the adjacent zone of a drainage channel. According to the principles of soil occurrence in the channel bed, four groups of damages might be distinguished: soil entrance into the channel during the tillage of a protective belt; inflow of washout products from the basin; scours of protective belts and washout of turf flumes of surface water discharge. The most frequent damages enhancing the washout of flumes and inflow of erosion products are total or partial tillage of the protective belt of a drainage channel. From the point of view of erosion process, the inflow of erosion products from the basin is considered as the most dangerous damages, which is inevitable when the width of protective belt is insufficient, particularly in places with deep turf flumes arranged.
Mostrar más [+] Menos [-]P-load in drainage water when slurry is applied
2005
Miseviciene, S.(Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.)E-mail:s.miseviciene@takas.lt
The paper presents study results on nutrient leaching in crop rotation fields where slurry was applied. The studies were carried out within the period of 2001-2003. As the study results have shown, phosphorus (P) concentrations much depend on drainage runoff. Increasing drainage runoff resulted in decreased P concentrations (r=0.7). P leaching also depends on the precipitation amount (r=0.83). Higher precipitation rates resulted in more intensive P leaching. P leaching more depended on the drainage runoff and the type of cultivated crops rather than on fertilization rates. P leaching also depends on the precipitation amount (r=0.83). Higher precipitation rates resulted in more intensive P leaching. P leaching more depended on the drainage runoff and the type of cultivated crops rather than on fertilization rates. P leaching decreased when higher amounts of phosphorus were accumulated in crop yield; the mineralization process of vegetative residuals that were left in the test field enhanced more intensive P leaching. When slurry was applied on crops of the test field, P concentrations never exceeded maximum allowable rates determined in normative documents of the environment of Lithuania. From the point of view of the environment protection, it is more expedient to apply slurry in spring because in this season of the year the leached amount of total P input into the soil is 37.5% less compared to its leached amount when slurry is applied in autumn.
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