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Bioenergy from pre-commercial thinning, forest infrastructure and undergrowth - resources, productivity and costs
2009
Lazdins, A., Latvian State Forestry Research Inst. Silava, Salaspils (Latvia) | Thor, M., Skogforsk - The Forest Research Institute of Sweden, Uppsala (Sweden)
This article is covering results of pre-commercial thinning, forest infrastructure and undergrowth harvesting field studies implemented in July, 2007 by Skogforsk and LSFRI Silava. A scope of the study was to estimate prime costs of biofuel production from small trees and to compare two types of harvester heads (Bracke C16.a and Ponsse EH25). The productivity in pre-commercial thinning expressed as trees per E0-h (effective hour) ranged between 53 (Ponsse) and 118 (Bracke) in the pine stand and 150 (Bracke) in the mixed spruce stand. In comparison the LVm3 (LV - loose volume) ranged between 9.9 (Ponsse) and 14.1 (Bracke) in the pine stand and was 13.0 (Bracke) in the mixed spruce stand. In the forest infrastructure (roadside ditches) harvesting productivity was 8.2 LVm3 E0-hE-1 for Ponsse and 12.5 LVm3 E0-hE-1 for Bracke. Productivity was economically insufficient in undergrowth removal, both in harvesting (Bracke) and forwarding (Ponsse) operations, respectively 1.1 and 2.6 LVm3 E0-hE-1. Prime costs of harvesting, forwarding, comminution and chip transport (50 km one direction) in pre-commercial thinning in calculation to LVL LVm-3 were 5.93 for Ponsse and 5.85 for Bracke. Prime costs in forest infrastructure in LVL LVmE-3 were 4.97 (Ponsse) and 6.36 (Bracke). Only Bracke was tested in the undergrowth, where prime costs were 37.55 LVL LVm-3. 'Environmental footprint' of biofuel production from small trees in terms of carbon (C) emissions ranged from 2.6 to 10.2 kg CLVmE-3, including road transport (50 km) to terminal.
Mostrar más [+] Menos [-]Forest change detection using knn (k-nearest neighbour)-based estimations of point-wise forest characteristics
2008
Jonikavicius, D., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania)
This paper discusses the usability of non-parametric knn (k-nearest neighbour) method to detect changes in forest areas from satellite images. Spot Xi images acquired 1999, main forest characteristics from field measured sample plots and data of conventional stand-wise forest inventory from the year 1988 were used to estimate the grids of following forest characteristics: mean age of main forest storey, diameter, basal area, height, volume per 1 ha, as well as the percentages of coniferous, soft and hard deciduous tree species. The differences of grids, created using stand-wise forest attributes from the 1988 inventory and estimated using the k-nearest neighbour methods were experimented to detect changes in the forest. 68.7-75.5% of areas, classified as the potential felling areas, were detected to be clear cut areas or young stands less than 15 years according to the data of stand-wise inventory of year 2003. Different settings for the methods investigated are evaluated, too.
Mostrar más [+] Menos [-]Structure and ecology of ash forest communities pruno-fraxinetum in Latvia
2008
Reihmane, D., University of Latvia, Riga (Latvia). Faculty of Geography and Earth Sciences
The vegetation of Pruno-Fraxinetum plant communities was described in 2004 – 2005 according to the Braun-Blanquet method throughout Latvia, in forests where common ash (Fraxinus excelsior L.) are dominant species in tree layer on moist soils. Classification of relevés (in total 52) by two way indicator species analysis (TWINSPAN) resulted in two variants of this association: typical variant (typicum) and variant with Filipendula ulmaria. Ellenberg indicator values were used to find out the relationship of flora with climatic (light, temperature, continentality) and edaphic (soil reaction, nitrogen, moisture) factors. Canonical correspondent analysis (CCA) was used to find out differences between two variants of Pruno-Fraxinetum. Results of this research have shown that these forests have complicated structure (form four vegetation layers, high species richness), which mainly depends on moist, rich eutrophic soils, usually with presence of limes. Main differential soil factors in ecological analysis are gradients of soil richness: moisture and nitrogen regimes. The influence of other factors was less expressed. Due to the human influence, especially drainage, the moist ash forests are decreasing and the species composition is changed. As Pruno-Fraxinetum forests in Latvia lie on the northern border of its distribution, the species composition differs from forests in the rest Europe; species characteristic determined by floodplain forests in Central Europe are absent.
Mostrar más [+] Menos [-]Forest values perceived by the public in forest sector
2008
Grege-Staltmane, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Forest is the ecosystem which consists of different related components and fulfils important environmental, economic, and social functions. Each of these components is of particular value in public perception. In the beginning of September, 2007 social research was carried out in Latvia in order to understand the meaning and importance of forest value on the questionnaire base. This survey focuses on how people, whose everyday life is related to forest sector, perceive forest values. The forest values were divided into thirteen factors. To determine the most important forest value, the participants’ answers significance was evaluated basing upon the concordance coefficient and using descriptive statistic methods. The research revealed that despite the multifunctional use of forest the basic value is granted to timber and forest land. As well as respondents were not shown significant differences expressing their opinions when they were divided into different groups (forest owners, forest sector employees and other). Results of the survey have shown that the public in Latvia are not able to value and calculate forest environmental and social functions.
Mostrar más [+] Menos [-]The analysis of silver birch (Betula pendula roth.) stands in state and private forests in Latvia
2008
Zalitis, T., Latvia Univ. of Agriculture, Jelgava (Latvia)
In Latvia, birch is the second most widespread tree species; the share of birch is higher in private forests. The Forest Research Inventory that was launched in 2004 provides credible and up-to-date information about all forests of Latvia irrespective of the ownership. The data from first three years’ data base of this Project has been used in the present study. The aim of this study was to analyse birch stands in state and private forests concentrating on different aspects: mixture degree, origin of the stand, productivity and quality of the stand. 735 sample plots were selected from the database for the analysis. The proportion of the birch stands in the private forests was slightly higher than in the state forests. There were more mixed stands in the state forests than in the private ones. The standing volume was higher in the mixed stands while the opposite was true for the current annual volume increment of birch. The main regeneration method in both the state and private birch stands was natural regeneration from seed. Artificial regeneration was used only rarely in the private birch stands. The productivity did not differ significantly between the state and private forests; the same was true for the quality, expressed by the outcome of veneer logs. The stand quality differed significantly among site types, being the highest in the forests on dry mineral soils and the lowest in the forests on drained peat soils.
Mostrar más [+] Menos [-]The wood resource availability influencing factors in private forests in Latvia
2010
Tunkele, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Marcins, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
The forests and woods are the main resources in Latvia. It is vital to understand the amount of wood resources that is being extracted from private forests now and in future in order to be able to predict the forest sector development and growth. The study objective was to identify the key factors in the wood resource availability and assess their role in private forests. In October 2009, the study was conducted to appraise the private forest owners the operational results and find out the future plans in connection to wood resource extraction. In the study a random sampling method was applied, where in the respondent selection the State Forest Service database information was used. In the study the respondent interviewing method CATI with computerized telephone interviews was used. In the selection of affecting factors the expert's method was applied. The study showed that only 25.40% of all private forest owners claimed that there was wood resources extraction in forests, but 29.50% of all private forest owners claimed that they were planning to perform the wood resource extraction in 2010. If the timber selling prices increased by more than 10 LVL per m3 in 2010, then 38% of all respondents claimed that they would increase the wood resource extraction in forests. The study data show that 30% of all private forest owners admit that there are growing stands in the forests, but they can’t be harvested, because road infrastructure is poorly developed or there are no roads in the forests.
Mostrar más [+] Menos [-]Promising European Union supported initiatives within private forest sector in Latvia
2010
Nikolajeva, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this paper is to evaluate all kinds of experiences with attractive EU funding for Latvia's private forest sector in the past and to generate new proposals for effective acquisition in near future. Latvian institution may learn from these experiences in order to improve their (acquisition) role in project proposals for the private forest sector. Consequently, the relatively underdeveloped Latvian private forest sector will get its highly needed support for better performance, and progress towards other, leading EU forest sectors. The possibilities for attractive financial EU support are reviewed through both historic experiences with the EU's 'Rural Development Program for 2007 – 2013' and the EU grants, designated for forestry projects. An extensive round of interviews is held with state forest owners and experts involved in forest management programmes and other dedicated EU forest funding initiatives. Following the expert interviews, two key indicators are developed to evaluate the support from the EU. Contacts with the EU countries (the Netherlands, Belgium, Finland and Poland) where similar forestry activities have been done as in Latvia were made. Research done in this work is unique as according to the author's information these countries do not have similar research related to the EU funds efficiency and Rural Development Program for 2007 – 2013. The successfulness of Latvian applications for the EU funding is one major indicator for further fund raising. The EU supported investments generally have higher economic results in comparison with their non EU funded counterparts.
Mostrar más [+] Menos [-]Evaluation of ecosystem services in riparian forests using benefit transfer method
2016
Saklaurs, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Krumins, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jekabsone, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this paper is to evaluate ecosystem services in riparian forests of Latvia using benefit transfer method. The core of benefit-transfer method is to transfer economic costs from one economic situation to another by using pilot indicators, thus saving time and monetary resources of the research. This method also is applicable for transfer of value of ecosystem services to research territories where such values have not been set. As to the evaluation of ecosystem services in riparian forests, data derived from these indicators are compared with the situation in riparian forest stands. Successful application of this method depends on the quality of existing research and their transferability. For example, the data on research of non-timber values can be used to set these values in riparian forests. Value of ecosystem services for 1 ha riparian forest stand in Latvia judging by 1) N and P removal (N - 8.14 euro haE-1 yE-1; P - 2.16 euro haE-1 yE-1); 2) Valuing carbon capture (478.6 euro haE-1 y-E1); 3) Valuing noise buffering (2.02 euro haE-1 yE-1); 4) Valuing air purification (NOx - 1332.5 euro haE-1 yE-1, NH3 - 216 euro haE-1 yE-1, particulate matter - 792 euro haE-1 yE-1); 5) Valuing pollination (timber - 15.25 euro haE-1 yE-1, non-timber - 4 euro haE-1 yE-1) total at 2850.67 euro haE-1 yE-1, which is significantly more than just the traditionally viewed timber value.
Mostrar más [+] Menos [-]Evaluation of results of forest regeneration after stump extraction in Finland
2012
Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Mattila, M., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The interest in stumps has increased with recent boost of the bioenergy in Europe. Fuel yield from stumps can be as high as from harvesting residues. The most valuable areas for stump extraction are spruce and pine stands on dry mineral soils. In Finland the utilization of stumps for energy is rapidly moving from the testing phase to forest practice. In 2005 the use of stump wood chips by heating and power plants totalled 0.4 mill. m**3, tripled the consumption of 2004, which corresponds to 14% of the total consumption of forest chips in Finland. Extensive whole-tree harvesting trials in Sweden demonstrate that removal of stumps and slash from clear-felled sites has a strong positive impact on natural forest regeneration. Results from Finland indicate that stump and slash removal can improve productivity and quality of subsequent re-planting of harvested forest sites. The majority of available studies on root rot control demonstrate that subsequent forest regeneration is more successful on sites where the stumps have been removed. The scope of this study was to evaluate quality of forest regeneration after stump extraction in Finland according to the national regulations in Latvia. Number, size, distribution and mortality of seedlings were estimated in 15 compartments. Additionally, moisture and compaction of soils were determined. Results of the study approved that regeneration of forest stands on fertile mineral soils after stump extraction was successful and combination of mounding with scarification during stump extraction provides sufficient growing conditions for new seedlings.
Mostrar más [+] Menos [-]Monetary value and social role of forest recreation services in Latvia
2011
Jankovska, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Straupe, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Recreation services are the forests’ non-market goods which constitute a substantial part of the total economic value and are important for the choice of multi-functional forest policies. However recreational services do not always have a market price and comparatively less literature applies value orientations to examine issues concerned with recreational use of natural resources. This research reports on the findings of the comprehensive, national-level study about the contribution of forest recreational services to Latvia’s national economy in 2009 and about the respondents’ declared choices, travel costs and willingness to contribute some money for improvement of amenities in a forest. Two general information sources were used to obtain the information - available statistical data and the contingent valuation survey to estimate the respondents’ choices and habits for recreation activities in the forests. Results show that forest recreation is very popular and highly valued in Latvia. The statistical analysis confirms that the significant differences exist between varied respondents’ socioeconomic groups in their objectives, choices and preferences to use the forest recreational services.
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