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Quality assessment of European ash Fraxinus excelsior L. genetic resource forests in Latvia
2015
Puspure, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Gerra–Inohosa, L., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Arhipova, N., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
In Latvia, two European ash (Fraxinus excelsior) genetic resource forests (GRF) have been designated in Skrīveri and Bērvircava. However, as the degree of damage of ash by the pathogenic fungus Hymenoscyphus fraxineus has increased, many stands have died and many do not comply anymore with minimum requirements for GRF. The aim of the present research was to evaluate and examine the quality of ash GRFs. In each forest unit, one 20×20 m plot was established, and the first (E3) and second (E2) layer projective cover of each species was determined in August 2014. All undergrowth and advance regeneration species were counted and the degree of ash damage by H. fraxineus was determined along a diagonal 25×1 m transect in each plot. In total, 101 plots were established. Quality evaluation was carried out according to the basic criteria for selection of GRF as well as based on criteria cited in other research. Their variation was established by using principal component analysis. Ash in layer E3 was better maintained in Skrīveri, but ash regeneration there was worse, as well as a higher degree of damage by H. fraxineus was observed. Ash regeneration density is significantly influenced by its cover on layers E3 and E2 as well as by tree species dominating the growth. The most valuable GRFs have been maintained in Skrīveri where 50% of units were rated of average quality and few of bad quality. In Bērvircava, 56% of forest units were of bad and very bad quality.
Afficher plus [+] Moins [-]Vegetation cover 47 years after wind storm and clearcut in western Latvia
2015
Purina, L., Forest Competence Centre, Riga (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Straupe, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Liepa, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Katrevics, J., Forest Competence Centre, Riga (Latvia) | Jansons, A., Forest Competence Centre, Riga (Latvia)
Wind is an important natural disturbance factor in a forest ecosystem. It creates gaps in a forest canopy, providing microenvironmental conditions, suitable for forest regeneration and affects the species composition of ground vegetation. Most of the studies analysing consequences of wind-storm have addressed short-term changes or influence the stand structure, but the aim of our study is to analyse ground-vegetation long time after windstorm in hemiboral forests. Data on ground vegetation cover have been collected in areas affected by the storm of 1967, where due to salvage-logging 200-400 m wide clearcuts were created. Sample plots (1×1 m) were placed in different distance from the edge of former clearcuts and projective cover of ground vegetation assessed using Braun-Blanquet method in Myrtillosa mel. forest type on 5 sites in north-western part of Latvia. Results reveal that in all sites species belonging to boreal, boreal-temperate and temperate biome were present, but their proportions varied between sites. In total 82 species of vascular plants were found, most frequent among them Maianthemum bifolium (L.) F.W.Schmidt (species characteristic to Norway spruce forests), Vaccinium myrtillus L. and Vaccinium vitis-idaea L. (associated with Scots pine forests) as well as Molinia caerulea (L.) Moench and Deschampsia caespitosa (L.) P.Beauv. (both characteristic to wet soils). Results suggest, that even 47 years after the storm microenvironmental conditions in the sites are not stable. Ellenberg’s indicator values reveal, that most of the sites are in semi-shade, cool and moist conditions, placed on acidic, nitrogen-poor (in few sites – also nitrogen rich) soils.
Afficher plus [+] Moins [-]Impact of biomass extraction method on damage to remaining trees in mechanized thinning of deciduous stands
2015
Prindulis, U., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A, Forest Competence Centre, Riga (Latvia) | Kaleja, S., Forest Competence Centre, Riga (Latvia)
Thinning of young forest stands is a contribution to the future of the stand development. Our study focuses on damage of the remaining trees and soil. Now it is common to see thinning of young stands with heavy forest machines, but most of these operations take place in commercial thinning. This study is focused on precommercial thinning to evaluate different mechanized thinning methods in relation to the damage done to the remaining trees and soil in deciduous tree stands. Data were collected in four stands where the average diameter of trees at breast height was 6.2 cm, the height of average trees - 9.5 m, but number of trees per hectare was more than 2900. The stands regenerate naturally. Damage was evaluated separately after harvester and forwarder operations. The study proves that forwarding makes much less damage to the remaining trees than harvesting. According to the study data, the traditional method results in the largest number of damaged trees, because operators need to cut all trees closer than 1.5 m from the target tree. Both schematic thinning methods result in significantly less damage. A statistically significant difference (p is less than 0.001) was found in a proportion of damaged remaining trees between all of the applied working methods. The smallest amount of damage is associated with complex symmetrical thinning method. The most damage appears during harvesting. The aim of this study was to compare three working methods of biofuel production in pre-commercial thinning using harvester John Deere 1070D with accumulating felling head Bracke C16.b in grey alder (Alnus incana) pure stand.
Afficher plus [+] Moins [-]Leaching and durability of copper treated Scots pine (Pinus sylvestris L.) wood
2015
Meija-Feldmane, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia)
Scots pine (Pinus sylvestris L.) is the most common wood species in Latvia. It is classified as not durable, therefore additional protection against microorganisms is needed prior its use outdoors. Presently Cu-containing wood preservatives are commonly used, but the biggest drawback is the poor Cu fixation, therefore raising concerns about the impact on the environment. Three types of specimens were used to carry out the experiments – untreated, Latvian originated Scots pine; Scots pine commercially treated with preservatives that belong to a group of Cu-boron-triazole (CBA) products; and Scots pine, impregnated with micronized-Cu solution using a standard full cell process. In order to make sure that all of the specimens are equal in their components, elemental analysis was performed and content of nitrogen (1.2 – 2.5 g kgE-1), carbon (485.5 g kgE-1), oxygen (456.0 g kgE-1) and hydrogen (55.6 g kgE-1) was determined. The treated specimens were leached according to the European standard EN 84. For micronized-Cu impregnated Scots pine the total Cu content in leachates obtained by atomic absorption spectroscopy was 0.15 mg gE-1 of wood, and 0.06 mg gE-1 of absolute dry matter with CBA preservative impregnated Scots pine wood. Subsequently, according to the European standard EN 113, treated Scots pine blocks were exposed to brown-rot fungus Coniophora puteana and to white-rot fungus Trametes versicolor for 16 weeks. Mass loss for wood treated with micro-Cu was 48.4% (484 g kgE-1) and 1.5% (15 g kgE-1) respectively, but for CBA – 49.5 % (495 g kgE-1) and 1.2% (12 g kgE-1). Both samples proved to be inappropriate for outdoor use (use class 3).
Afficher plus [+] Moins [-]Implementation of management functions: based on the example of non-government organisations in Kaunas district
2015
Marcinkeviciute, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Zukovskis, J., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
This article deals with conception and particularity of management process and functions of non-governmental organisations (hereinafter referred to as NGO), as well as peculiarities of management functions of NGO. Empirical research results of implementation of NGO management functions in Kaunas District have been presented, the major advantages and disadvantages of implementation of NGO management functions in Kaunas District have been pointed out. With reference to the data of theoretical analysis and empirical research, the directions towards development of problematic areas of NGO management functions have been indicated and justified, highlighting the elimination of drawbacks to the implementation of management functions.
Afficher plus [+] Moins [-]Geographical tendencies of main produce exports of Latvia 2000-2013
2015
Berjoza, A., University of Latvia, Riga (Latvia) | Paiders, J., University of Latvia, Riga (Latvia)
Recently economic development has been an issue of intense research and discussion in an academic society. Many facets of countries’ economic development were examined, including foreign trade. As a foundation of international cooperation, this indicator is relevant in observing one’s internal development and external ties. In case of Latvia, this topic is heavily influenced by economists, and the geographical perspective is quite underdeveloped. In this research, the economic ties of Latvia were explored through the analysis of its main export groups in sectors of agriculture, forestry and fisheries throughout the first decade of the 21st century. With the aim of establishing clear ties between Latvia and its major export markets, the statistics of foreign trade was analysed using frequency analysis. It can be reported that in general Latvian export markets are closely located and consist of the Baltic Sea Region countries such as Denmark, Germany, Russia and others. Despite the differences in commodity group destinations, it can be clearly stated that a division of trade flow still exists, separating it into two directions - Eastern and Western, where the former allocates the majority of Latvian processed commodities and more sophisticated goods, and the latter consumes raw materials and less transformed materials. This arguably shows a difference in demand in Western and Eastern markets, where the first mostly requires materials for its own industry, while the latter procures them for consumption on the local market, again pointing to a complexity of reforms required for the Latvian economic focus turning towards Western markets.
Afficher plus [+] Moins [-]Role of local action in addressing regional development and social problems in Latvia
2015
Krievina, A., Latvian State Inst. of Agrarian Economics, Riga (Latvia) | Leimane, I., Latvian State Inst. of Agrarian Economics, Riga (Latvia) | Melece, L., Latvian State Inst. of Agrarian Economics, Riga (Latvia)
The objective of the paper research is to assess the role of the implementation of the local development strategies (LDS) elaborated by the local action groups (LAGs) in the regional development and addressing social problems in Latvia. The paper examines the role and place of LDS in territorial development planning in Latvia, carries out thematic analysis of the projects implemented under the LDS as well as tries to assess the LEADER approach impact on regional development and addressing of social issues on the local level. The authors use unpublished data on LEADER projects and apply quantitative and qualitative analysis methods. Most of LEADER projects have been implemented to facilitate the development of infrastructure related to recreation and quality leisure time as well as culture and sports. Rural inhabitants have noticed positive changes in their local territory introduced by the LEADER approach. Though, in order to enhance the role of LAGs and LDS in addressing regional development and social problems at local level, it is advisable that the potential interaction of the activities provided by all regional planning documents is observed when determining priorities at regional level (presently the place and role of the LDS has not been formally defined), while implementation of the LDS should pay more attention to long-term effects and even accomplishment of target priorities.
Afficher plus [+] Moins [-]Determination of the importance and performance of factors affecting rural tourism homestead choice in Lithuania
2015
Grigaliunaite, V., Lithuanian Univ. of Health Sciences, Kaunas (Lithuania) | Pileliene, L., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
rural tourism homestead choice in Lithuania. The aim of the research was to determine the balance between the importance and performance of factors affecting the choice of rural tourism homestead in Lithuania. The questionnaire research was provided in Lithuania in 2014. Tourists’ evaluations regarding five exogenous latent variables: ‘accommodation and catering’, ‘activities in destination’, ‘natural features’, ‘destination aesthetics’, and ‘environmental preservation’, and four endogenous latent variables: ‘destination marketing’, ‘perceived value’, ‘satisfaction’, and ‘loyalty’ were measured. The total effects for the specific endogenous constructs in the structural model (importance) and the average values of the latent variable scores, rescaled to a range of zero and 100 (performance) were measured to compose the importance performance grid. The research results indicate that the most important factors for tourists while choosing a rural tourism homestead in Lithuania are ‘destination marketing’, ‘environmental preservation’, ‘perceived value’ and ‘satisfaction’. Moreover, the highest share of the total investments allocated to satisfy tourists and enhance the level of loyalty should be accrued to the improvement of ‘destination marketing’ and ‘environmental preservation’.
Afficher plus [+] Moins [-]Evaluation of the regional tourism atractiveness
2015
Dapkus, R., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Dapkute, K., Vilnius University (Lithuania)
The paper covers theoretical analysis of the tourism development in rural regions as well as the public administration role in tourism sector management in order to evaluate, plan and maintain tourism resources in the region. In the paper, there is presented a discussion on some proposed methodologies for the tourism structure and resources evaluation, in order to compare attraction potential of territories for the tourism development (competitiveness between regions). The tourism planning and management process should be proceeded at various levels of public administration institutions in order to avoid negative influence from different branches of the economy, preserve nature, historical and cultural heritage, ingeniously and cost-effectively use EU Structural funds and national budget resources for the tourism infrastructure development in order to prevent unwanted competition between local and regional public administrations, stimulating them to act jointly in order to achieve synergy attracting tourists to visit neighbouring regions. How to achieve mentioned goals the questioning of the tourism development experts has been performed, and some results of it are presented in the paper. Conclusions on the performed research and proposed methodologies as well as some suggestions for the better tourism development management at the regional level have been presented.
Afficher plus [+] Moins [-]Impact of agricultural landholding size on the land fragmentation
2015
Sikk, K., Estonian Univ. of Life Sciences, Tartu (Estonia) | Maasikamaee, S., Estonian Univ. of Life Sciences, Tartu (Estonia)
Land fragmentation is a problem in Europe, and Estonia is not an exception in this respect. Parcel size is widespread characteristic to describe the level of fragmentation. The aim of the study is to find out if there is difference of fragmentation among different groups of landholdings by size. In order to characterise land fragmentation, were calculated the Januszewski and Schmook indexes, average parcel size and average distance from the gravity centre of each landholding to its parcels. Results showed a high level of fragmentation of Estonian agricultural landholdings. There is a high variety of fragmentation inside and among the investigated groups. The average value of Januszewski index for all groups is 0.626, and the average value of Schmook index for all groups is 0.462. The average parcel size for all groups is 7.02 hectares and average distance from the gravity centre of each landholding to its parcels for all groups is 1.57 kilometres.
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