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Litter invertebrate communities in pine forests of different age (Baranivka area, Ukraine) Full text
2012
Kalynovskyi, N., Zhytomyr National Agroecological Univ. (Ukraine)
Litter invertebrate communities in pine forests of different age (cut, six-year-old, 45-, 62-, and 105-year-old) in the Baranivka area of Zhytomyr Polissya (northwestern part of Ukraine) were studied. Samples were collected in April, August, and November 2011. 99% of extracted invertebrates were represented by mites (Acari) and springtails (Collembola). With forest age, the following tendencies were observed: mean absolute density of mites, springtails, and all litter-inhabiting animals increased; relative abundance of mites increased, but relative abundance of springtails decreased; taxonomic richness of invertebrate communities increased. In all samples, the most represented taxon was suborder Oribatida. The most diverse litter invertebrate community was in the 45-year-old forest. Similar compositions of invertebrate community were in the 45-, 62-, and 105-year-old forests as well as the cut and six-year-old ones.
Show more [+] Less [-]Thermal weed control in Norway spruce (Picea abies (L.) H.Karst.) nursery Full text
2012
Silingiene, G., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Vasinauskiene, R., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Racinskas, J., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Growing of economics and new technologies has caused the environment pollution and more intensive use of natural resources. The principles of stable and balanced forestry became more and more important. Ecologization forests economy directly and indirectly impacts environment, water, air, landscape. It is not allowed to use chemicals in ecological farms. In Lithuania the number of ecological farms is growing that is why the new effective ecological methods are needed to protect seedlings from weeds. Alternative to mechanical control of weed is to use high temperature. In ecological farms weed control after sowing time is pursued in mechanic, and recently in thermal way. In thermal weed control the surface of soil remains mechanically undisturbed, the roots of cultural plants remain undisturbed, too. These features are very important in forest nurseries, where different kinds of tree species are growing. Seedlings are very small at the beginning of growing, so mechanical weed control is difficult. Thermal weed control could be a good alternative. Comparable data of 2009-2011 thermal weed control research in Norway spruce (Picea abies (L.) H. Karst.) nursery is given. The efficiency of destroyed 16 weed sorts using thermal and mechanical ways of weed control is given. Thermal weed control for short age weeds is 20.3% more effective in comparison with mechanical way. Mechanical way is 35.2% more effective for perennial weeds. It was detected that in order to control weeds of different growth stages, it is necessary to use different treatment time of damp water stream.
Show more [+] Less [-]Below-ground biomass production in young stands of Scots pine (Pinus sylvestris L.) on abandoned agricultural land Full text
2012
Bardulis, A., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Liepa, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Tree roots take up a high proportion of forest biomass, and nowadays we use different methods to estimate the root biomass. Methods vary greatly due to the different studies and different excavation methods used. In the summer 2010, a study of the below-ground biomass of young Scots pine Pinus sylvestris L. stands was carried out in central Latvia. In this paper, different below-ground biomass fractions data of 10 sample trees from the abandoned agricultural land plantations were approximated by allometric functions depending on tree stem diameter at breast height 1.3 m (DBH). The main objective was to determine the average below-ground biomass and approximated below-ground biomass fractions by allometric functions depending on tree DBH of young stands of Scots pine on abandoned agricultural land. Our regressions offer good overall approximations of the data. DBH – stump, coarse root and small root and total biomass regressions were highly significant (p is less than 0.001). The most substantial part of total below-ground biomass was from stumps (45%). The smallest shares of the biomass were coarse roots 38% and small roots 16%. The largest portion (52%) of the total fine-root biomass of 12- and 14-year-old Scots pine stands was located at a depth of 0–10 cm, decreasing in deeper mineral soil layers. Total dry (DM) below-ground biomass including fine-root biomass was 19.0 ±5.2 t DM ha-E1.
Show more [+] Less [-]Evaluation of forest regeneration results after stump extraction in Joint stock company ''Latvian State Forests'' Full text
2012
Zimelis, A., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdans, V., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
With the increase in demand for renewable energy resources, new studies are carried out about under - utilized resources, namely, stumps. To begin to use stumps in industrial application, it is necessary to find out stump extraction influence on the environment, biodiversity, forest regeneration and other important factors. In Zemgale forestry, Misas and Klīves forest districts managed by Joint stock company “Latvian State Forests” (LSF) study on stump extraction in woodlands where clear-cuttings done in 2006 was carried out in the block No. 177, compartments No. 1 and 5, as well as the block No. 176, compartments No. 3 and 9. In these territories two research objects were made where in November-December 2007 stump extraction as well as soil preparation were performed. Main tasks of the project were to evaluate the results of forest natural seeding and coppice ingrowths in natural regeneration areas and evaluate the use of different methods for artificial reforestation with spruce and pine containerized seedlings. It was observed that more seedlings were cut off in the areas where soil scarification with stump extractor was performed if compared to areas prepared with a disc trencher.
Show more [+] Less [-]Churchyard elements in Latgale Upland [Latvia] Full text
2012
Markova, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
Churchyard of Latgale Upland is one of the most important parts of cultural historic space of Latvia. The study is based on the materials from expedition made in summer and autumn 2011, as well as on literary studies. Architecturally compositional form of the church is a key part of the landscape, supplemented by other landscape elements. Research and evaluation of the individual elements give specific cultural space characteristics of each investigated area. Visibility in the main view points and links with residential buildings for the churchyard is vital. Each study of landscape area schemes formation is based not only on the church as a domination point expression. Separate churchyard elements - crucifixes, procession paths, burial area, meditation area and a planting in church gardens - are important in describing churchyards. The aim of the research was to find most common elements in churchyards to establish general guidelines for recording and evaluation of the churchyard in Latgale Upland in future. In perspective that could be used as basis for making the landscape typology. Results showed typical landscape elements in the churchyard. In describing churchyards is important to divide typical and unique elements. The research provides information that is important for the further local territorial development plans, focusing attention on the region’s cultural values and identity preservation.
Show more [+] Less [-]Contamination problems in former military areas: case study in Riga [Latvia] Full text
2012
Burlakovs, J., University of Latvia, Riga (Latvia) | Gorbunovs, E., University of Latvia, Riga (Latvia)
Contamination of urban areas is directly connected with the lack of adequate waste management planning. Problems mostly arise in former military bases, garages, warehouses and areas with other facilities. For many decades environmental problems caused by pollution in areas of military use were not managed in Latvia. The aim of this research is to assess visual environmental quality and study heavy metal contents in soil of ‘Jaunais Mežaparks’ after demolishing works in the capital of Latvia – Riga, as well as to provide comparison to the former military ‘Daugavgrīva’ site. Research was carried out from November 2011 to February 2012 by soil sampling and further analysis and comparison of the heavy metal content in soil with target and boundary levels in legislation. ‘Jaunais Mežaparks’ is a former military area which is planned to be reused in future. The former military site is planned to be used as the residential neighborhood and is situated close to important recreational object in Mežaparks area – Lake Ķīšezers. According to Riga Development Plan old military sites must be remediated in accordance with environmental legislation if the contamination exceeds critical concentration values. Thus, this case study includes assessment of visual pollution as well as soil heavy metal contamination study. Recommended actions as well as direct remediation technologies to reduce the poisonous impact of contamination to environment in this area are proposed.
Show more [+] Less [-]The influence of different humus layers on the drainage runoff during different seasons Full text
2012
Miseckaite, O., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Kincius, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Hydro-physical properties of heavy or presses soil as well as water regime may be improved by various ways, taking into account the texture of soil and climatic conditions. Drainage is the tool for productive farming and economic benefit generation. Hydrological activity of drainage typically depends on project installation quality, anthropogenic and climatic factors. It is important to assess drainage activity under different meteorological conditions. One of methods to improve drainage performance is its installation with thickened humus layer. Lithuanian soil humus layer is close to arable layer and is equal to approximately 20–25 cm. The impact of humus on heavy-textured soil is multiple, since not only moisture regimes, biological activity, sorption capacity, chemical and biological characteristics, stability of plant nutrition are related with its quantity. The dynamics of drainage activity in soil with thickened (up to 40–50 cm) humus layer and with humus layer of natural thickness (20–30 cm) during various seasons of period of 1989–2009 is reviewed. Especially important indicator of drainage functioning – water runoff dynamics. The present article analyses the variation of climatic conditions and drainage runoff in the object. It is determined that the lowest quantity of precipitation in the researched territory during the research period is in spring and winter but the highest – in summer and autumn. During the research period the highest drainage runoff in the field I was during winter season (46.3%), in the field II – in winter and spring almost the same (32–33%).
Show more [+] Less [-]Risks in agriculture and their assessment methods Full text
2012
Girdziute, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
Agriculture is a unique sector, because it is associated with negative outcomes stemming from imperfectly predictable biological and climatic variables. These variables include natural adversities (for example, pests and diseases), climatic factors are not within the control of agricultural producers. So in agriculture it is very important to identify and evaluate risk, only then decisions made in farm will bring profit and other positive results. Scientific literature distinguishes a lot of methods for risk evaluation, but it is not clear what methods could be adapted in agriculture sector. This article presents main risk types in agriculture and their features as well as introduces most popular risk evaluation methods and their possible use in assessing risks in agriculture.
Show more [+] Less [-]Economic calculation of short rotation willow plantations in Latvia Full text
2012
Makovskis, K., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Bite, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Short rotation forests (SRF) can be used for biomass production for energy applications in Latvia. Establishment of plantations could be one of possibilities how to reach targets of renewable energy resource (RES) consumption of 40% in 2020. In Latvia’s conditions, one of most suitable species that could be used for SRF is willow (Salix sp.). Abandoned agricultural lands are suitable for establishment of plantations. Productivity of 8 oven- dried tons (ODT) ha-1 year -1 can lead to Rate of Return (IRR) of 17.1% and Net Present Value (NPV) 1099 Latvian Lats (LVL) if the biomass price is 33 LVL ODT-1. Establishment, harvesting and transporting costs account for 88% of the total cost of production. Price of wood chip and fuel plays the most important role in economics of plantation.
Show more [+] Less [-]Policies related to volunteer work in Latvia Full text
2012
Jaunmuktane, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Volunteer work has been identified as a relatively new kind of leisure activities. It plays an important role in various, at the same time it is a great possibility to learn, acquire new skills and accumulate human capital while taking part in volunteer activities. Therefore, the objective of the study is to research the policies related to voluntary work and their relevance in realization and development of volunteer work in Latvia. Theoretical literature shows that in Latvia the volunteer work is mentioned in some policies – economic, youth policies and civil society. In the framework of economic policy successful development of volunteering enhances the progress of economic processes in the state in two ways by making contributions to Gross Domestic Product; by accumulating person’s human capital, results illustrate that although the term “voluntary work” has a long history, infrastructure for realization of the voluntary work has not been developed in Latvia, and regulatory enactments do not cover voluntary work in an adequate manner. After the analysis the author believes that volunteering is widely discussed in the youth policy as there is law and a range of structured documents where aspects of volunteer work are mentioned. According to the results of research, in the frame of civil society it must be noted that in Latvia the voluntary work movement has to be examined in the context of the establishment of non-governmental organizations because voluntary work movement started to develop in a purposeful and organized manner only in 1998 in non-governmental organizations.
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