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Climate suitability effect on tree growth and survival for Scots pine provenances in Latvia
2014
Rieksts-Riekstins, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Smilga, J., Forest Sector Competence Centre, SIA, Riga (Latvia) - MNKC | Baumanis, I., Forest Sector Competence Centre, SIA, Riga (Latvia) - MNKC | Ray, D., Forest Research, Roslin, Midlothian, Scotland (United Kingdom). Northern Research Station | Connolly, T., Forest Research, Roslin, Midlothian, Scotland (United Kingdom). Northern Research Station
Climate in Latvia has been changing in last decades, and it is predicted to continue changing; therefore, it is important for forestry sector to understand how these climatic changes might affect tree growth and survival. In order to assess climate suitability effect on Scots pine (Pinus sylvestris L.) provenances in Latvia, height and survival data from a Scots pine provenance trial located in three geographically distant places in Latvia were analysed together with several climatic indices. Provenances in the corresponding trial originated from Latvia, Poland, Germany, Belarus, Russia and Ukraine. Thirty year average climate data values from 1961 – 1990 for the 64 origins of provenances were acquired from the WorldClim project. Correlation analysis between provenance average values for height and survival and climate index values for the origins of the provenances confirm that there is a relation between these amounts, and the relation differs between the three site locations, indicating that suitability of climate is an important factor affecting the results of provenance trials. Cluster analysis confirmed that provenances from distant origins might have a very similar growth and survival rates; therefore, geographical location of the provenance origins cannot be considered as the only influential factor on these rates and the results from provenance trials have to be analysed together with climate data in order to make conclusions about the suitability of the provenances.
اظهر المزيد [+] اقل [-]Vertical price transmission along the potato supply chain in Lithuania
2018
Jurkenaite, N., Lithuanian Inst. of Agrarian Economics, Vilnius (Lithuania) | Paparas, D., Harper Adams Univ., Newport, Shropshire County (United Kingdom)
Potato sector is one of the competitive areas of the European Union (EU) agriculture. Although Eurostat declared that in 2015 Lithuanian share in the EU-28 harvested production was modest and composed only 0.7%, according to Food and Agriculture Organization of the United Nations (FAOSTAT), this crop remained on the list of top 10 commodities by net production value in Lithuanian agriculture. However, over the past decades the Lithuanian potato sector survived undesired transformations. The aim of this paper is to analyse the changes of the main indicators, related to the potato sector, and vertical price transmission among the chain of potatoes in Lithuania. The conducted research indicates the most important development trends of the potato sector and applies econometric techniques to investigate if there is any long-run relationship between the farm and retail prices of potatoes for the period of 2010 to 2016. Although the statistics show the shrinking production and domestic consumption of potatoes in Lithuania, the analysis of the vertical price transmission does not provide evidence of market inefficiencies. The Johansen cointegration test confirms the existence of a long-run relationship between the farm and retail prices, while the Granger causality test shows that there is a bidirectional causality between the examined series. The M-TAR model does not provide evidence of the farm and retail price asymmetry in the long run.
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