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Improved activity data for accounting greenhouse gas emissions due to management of wetlands
2018
Butlers, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Ivanovs, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The study represents results on remote sensing methods based evaluation of land use and land use changes in former and existing peat extraction areas in Latvia. The aim of the study is to elaborate activity data set for the National GHG inventory for the wetlands remaining wetlands for peat extraction. The study results provide sufficient data for application of the default emission factors for the peat extraction sites and flooded lands. Abandoned peat extraction fields, which are not yet afforested, flooded or rewetted, should be reported as peat extraction sites following a conservative approach in application of the emission factors. The study results can be used to report land use changes since 1990; however, linearized approach in calculation of the land use change may result in overestimation or underestimation of GHG emissions in certain periods of time. According to study results, the area of peat extraction sites is considerably bigger than currently reported in the National GHG inventory, mainly due to considerable areas of abandoned peat extraction fields. Flooded lands may be a significant source of emissions and should be introduced in the National GHG inventory to secure consistency of reporting. Methodology for calculation of GHG emissions from flooded lands should be also elaborated. It is also necessary to elaborate emission factors for fertile and no fertile peat extraction sites and continue work on separation of different soils in the inventory to increase accuracy of calculations.
Mostrar más [+] Menos [-]Possibilities of application of orthophoto maps in determination of land degradation
2016
Cintina, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Baumane, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
Aim of the paper is to explore the possibilities of application of orthophoto maps in determination of land degradation. One of the forms of remote sensing is aerial photography. Orthophoto maps are made from aerial photography with specialized software orthophoto maps were analysed in perspective for several years – from 2005 to 2011.The results are based on the expert. With each year possibilities of application of orthophoto maps are expanding. During the research, data of survey and SWOT analysis of determination of land degradation by orthophoto maps. The study results prove that based on orthophoto maps mainly, it can be detected the following land degradation processes – agricultural land overgrowing with bushes and abandonment of built-up areas.
Mostrar más [+] Menos [-]The impact of plot spatial properties on the conversion of arable land into brushwood
2015
Maasikamaee, S., Estonian Univ. of Life Sciences, Tartu (Estonia) | Mandel, M., Estonian Univ. of Life Sciences, Tartu (Estonia)
Land use change has caught scientist’s attention all over the world and in the perspective of globalisation the pressures on agricultural land are increasing. However, the agricultural land abandonment is still evident. This phenomenon has no single definition and its driving forces are varying among different regions and countries. In this paper agricultural land is considered as abandoned while there is evidence of shrub and bushes on agricultural land according to the orthophoto and Estonian base map comparison. The aim of this paper was to test the impact of arable land plot spatial properties: plot area, ratio of arable land area in the surrounding of plot and plot compactness. General hypothesis is that brushwood will more likely occur on the arable land plots with poor spatial properties than on arable land plots with good ones. The study was conducted in 15 rural municipalities across Estonia. Results are showing some impact of the spatial properties on the arable land plots conversion into brushwood. In nine municipalities out of 15, there was an arable plot area without brushwood larger than plots with brushwood and the percentage of arable land area surrounding plots without brushwood was higher in other 9 studied municipalities. As expected, the uncompact arable land plots tend to have more likely brushwood on them than the compact ones. Study results show that the impact of plot area and the ratio of arable land in surroundings of plots on the conversion of arable land plots into brushwood need further studies.
Mostrar más [+] Menos [-]Economical motivation of birch forest plantation
2001
Zudrags, M. (Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Forestry. Dept. of Silviculture)
More than 17,5% of Latvian agricultural land is abondoned, therefore effective use of this land is a significant issue in national economics. One of the alternatives of how to use abandoned agricultural land is its afforestation by birch. The present research is based on the Scandinavian experience. Calculations have been made on the necessary investments and management costs. The recovery and possible impact on price changes in raw birch materials are analysed as well.
Mostrar más [+] Menos [-][Investment appraisal of agricultural land afforestation]
2002
Zudrags, M. (Latvia Univ. of Agriculture, Jelgava (Latvia))
Today more than 17.5% of agricultural land is abandoned in Latvia. Effective use of this land is essential for rural development planning, as well as growth of national economics. Afforestation is one of alternative uses of abondoned and marginal agricultural land. Requisite investments and management costs are calculated for forest plantations of pine, spruce, birch and aspen. The analysis of investment appraisal is based on several criteria - net present value, internal rate of return, benefit/cost ratio and equivalent annual annuity.
Mostrar más [+] Menos [-]Changes in semi-natural grassland distribution in relation to common agricultural policy 2014–2020 area-based payments in Latvia
2023
Rusina, Solvita | Vacere, Gundega | Lakovskis, Peteris | Ievina, Linda
Semi-natural grasslands (SNG) are essential in the context of farmland biodiversity. The Common Agricultural Policy (CAP), on the other hand, is an important tool for the continuation of the management of semi-natural grasslands. Explicit knowledge on the pattern of grassland area changes is important to foster a more effective use of CAP for grassland biodiversity conservation. Our aim was to determine the habitat-specific changes in the distribution of Latvian SNG across different management regimes. Based on state-owned geospatial data of SNG distribution in 2014 and 2022, we assessed changes in semi-natural grassland areas over nearly ten years by analysing grassland management and spatial distribution including areas inside and outside the Natura 2000 network. The spatial distribution of SNG remained similar in both periods. Eastern Latvia retained the highest share of SNG while the central part showed the most pronounced increase in new localities of SNG due to extensive habitat mapping carried out in recent years. Abandonment appeared as a more important threat to SNG in the Natura 2000 network and more profoundly to unproductive habitat types while transformation into arable land and grassland intensification was a considerable threat to SNG outside the network and to more productive habitat types. We suggest that agri-environment schemes should address the different needs of SNG in the Natura 2000 network and outside it.
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