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Structure of mature mixed pine-and-spruce stands on postagrogenic lands in Leningrad region, Russia
2018
Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Belyaeva, N., Saint-Petersburg State Forest Technical Univ. named after S.M. Kirov (Russian Federation);Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Janusz, S., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation)
The objective of this study is to assess the qualitative and quantitative characteristics of pine (Pinus sylvestris) and spruce (Picea abies) stands growing on lands that were previously in agricultural use in the Leningrad region. Sample areas of mature mixed pine-and-spruce prevailing stands were studied. The taxation has revealed that the average height and diameter of the stands under study are greater than those in mixed modal stands of these species on forest lands. The analysis of the results of the study was performed by dispersion, correlation and ranking methods. To determine the competitive relationship between species, the coefficients of skewness, and kurtosis were calculated. For coniferous stands growing on former arable lands, the distribution of diameter classes for pine and spruce differ depending on the prevalence of species. The predominance of one of the coniferous species in the stands leads to an aggravation of competition, which manifests itself in positive coefficients of asymmetry. The skewness indicators and the kurtosis of tree trunks distribution clearly demonstrate the strengthening and weakening of competitive relationships in the stand. Competitive relationships between species are more balanced in stand compositions that include more than half of spruce and about 40% of pine, which results in the largest volume of stemwood. A more powerful root zone of trees in the former arable soil allows mixed stands of spruce and pine to produce a larger volume of wood than in pure stands of pine and spruce for the investigated region.
Mostrar más [+] Menos [-]Phytophthora genus pathogens isolated from rhododendrons in Lithuania
2018
Snieskiene, V., Vytautas Magnus Univ., Kaunas (Lithuania). Kaunas Botanical Garden | Stankeviciene, A., Vytautas Magnus Univ., Kaunas (Lithuania). Kaunas Botanical Garden
Rhododendron spp. plants were surveyed for Phytophthora infection in Lithuania during 2010 – 2016. This study aims to identify Phytophthora genus pathogen which infects rhododendrons in Lithuania. Samples were taken from young sick plants with visible infection symptoms. Soil sampling was performed from the rhizosphere of sick plants. DNA from soil and plant was tested for the presence of Phytophthora genus pathogens. Data showed positive results of Phytophthora genus specific probe during real-time PCR. All tested diseased leaves and soil samples have indicated Phytophthora sp. infection during Alert-LF® Phytophthora spp. analysis. The extracted DNA concentrations were not very high for Phytophthora species identification, but in most cases, it was high enough for further researches.
Mostrar más [+] Menos [-]Effectiveness of sedimentation ponds in forest drainage systems in heavy rain periods
2018
Kalnins, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Petaja, G., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Establishment of sedimentation ponds is a method to reduce the negative impact of forest management (fellings, drainage) on the quality of nearby rivers, lakes and streams. The aim of the study was to determine the efficiency of sedimentation ponds in forest drainage systems during high precipitation periods. Nine sedimentation ponds with different drainage areas were analysed. The sedimentation ponds are located in the northern part of Latvia on different types of soils and managed by the Joint Stock Company ‘Latvia’s State Forests’. In order to determine efficiency of these ponds the following parameters in water samples were measured: nitrate (NO3 -), ammonium (NH4 +), phosphate ion (PO4 3-), total nitrogen and total suspended solid concentration. The amount of precipitation was taken into account. Results show that there is a correlation between the amount of precipitation and concentrations of total suspended solids and total nitrogen. Ammonium ion concentration was the only parameter that significantly exceeded water quality standards in Latvia. Only one of the objects had high concentration of pollutants, which could be explained with the peaty soil of its drainage area. In further studies data should be collected more frequently, three or four days during one precipitation period.
Mostrar más [+] Menos [-]Changes of the forest land area and spatial structure in urban landscapes of Lithuania
2018
Tiskute-Memgaudiene, D., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The territorial planning and the management of urban surfaces force the decrease of green spaces in urban landscapes. As the urbanization process during past decades of the last century was quite intensive not only in Europe but also in Lithuania, findings describing changes of forest cover as well as spatial structure of the forest land are requested. The aim of this study was as follows: first, to calculate and compare areas of the forest land in six major cities of Lithuania in 1950 and 2011, second, to evaluate the spatial structure of the forest land by investigated cities within the period of 1950 – 2011. Methods of descriptive statistical analysis and spatial analysis using ArcGIS and MS EXCEL software were used. The study was based on two geodatabases, representing the forest cover in 1950 and 2011. Results of this study revealed that areas of the forest land increased in all investigated cities excluding Panevėžys city. The increases of areas of the forest land were discovered to vary from 0.8% to 9.5%. The largest increase was found in Vilnius city (9.5%), the smallest – in Šiauliai city (0.8%). The decrease by 0.9% of the forest land was found just in Panevėžys city. No significant changes of the forest land spatial structure were found in largest cities of Lithuania, i.e. Vilnius city and Kaunas city. The spatial structure of forest land in other investigated cities tended to degrade.
Mostrar más [+] Menos [-]Food research opportunities and challenges: methods in food safety and functional food development: a review
2018
Karus, A., Estonian Univ. of Life Sciences, Tartu (Estonia) | Karus, V., Estonian Univ. of Life Sciences, Tartu (Estonia)
Large amounts of waste and by-products which are suitable for further use are generated in the food production chain. Globally, one-third of the food produced virtually becomes waste, in total 1.3 billion tonnes per year. The livestock sector is experiencing new challenges in the food and feed supply chain and waste valorization and there is a considerable diversity in animal origin food processing systems and broad knowledge base of expertise across Europe. However, due to local food production peculiarities, there is a considerable discrepancy in the waste management and processing methodology. An increasing amount of different novel feed and new functional food is available. These new products require a proper authentication and health and safety verification. Available know-how is increasing exponentially and therefore the potential for new and old bioactive component production from various currently poorly used materials is huge. Similarly, our knowledge about threats and food/feed safety is increasing. It is crucial to keep the balance between these processes. There are also several obstacles in data harmonization (data collection, used methodologies and reliability) and in data quality (lack of the comparability and completeness). The aim of the paper is to summarize the challenges in food research related to latest developments in methods.
Mostrar más [+] Menos [-]Disturbance of the functionality in immunocompetent organs of chickens due to accumulation of cadmium
2018
Vasiljeva, S., University of Latvia, Riga (Latvia) | Basova, N., University of Latvia, Riga (Latvia) | Smirnova, G., University of Latvia, Riga (Latvia)
The high toxicity, bioaccumulative and increased distribution of cadmium (Cd) in the environment, makes it the most dangerous to any biological system, including immune system in human and animals. The effect of dietary intake of Cd (8.25 mg per kg) on accumulation and distribution of this heavy metal in various tissues, and functional changes in organs of immunity (thymus, bursa of Fabricius, spleen) in 35-day-old broiler cockerels were investigated, using biochemical and immunological methods. Significant increases in the Cd concentration both in central immunocompetent organs (thymus, bursa of Fabricius) and peripheral (spleen) were established. Excessive tissue level of Cd induced the prooxidative effect of this heavy metal in the organs. It was manifested in an increase of cell membrane lipid peroxidation (the enhanced malondialdehyde (MDA) concentration) in immune system organs. The oxidative stress resulted in immunocompetent cell damage. The fall of vital dye absorptive ability of immunocyte indicated the increase in the injured cell number. This harmful effect is in accordance with T- and B (C3) – population prominent depletion, organ relative mass reduction, and growth retardation in chicks, and was established as a result of dietary Cd loading for 5 weeks of the experiment.
Mostrar más [+] Menos [-]Rye and oat crispbread improvement with biologically active substances from plant by-products
2018
Konrade, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Klava, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Vegetable processing in food industry results in significant number of by-products – peel, mark, bark, seeds still rich in bioactive compounds. The objective of this study was to investigate the stability of total phenolic content (TPC) and antioxidant activity after high temperature short time (HTST) extrusion cooking of a rye and oat- based matrix with addition of apple, carrot and pumpkin by-product flour (BPF) in various amounts (5%, 10%, 15% and 20%). Extrusion was performed with co-rotating twin-screw extruder (compression ratio 8:1) at Ltd MILZU. The main drive of extruder was provided with a 7.5 HP motor (400 V, 3 HP, 50 cycles). Temperatures for extrusion zones were 125 °C /135 °C /145 °C. TPC was determined using the Folin Ciocalteu method. Antioxidant activity was evaluated by free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant scavenging activity. TPC in cereal-based crispbread was 62.03 ± 0.15 mg GAE gE-1 DW before extrusion and 37.73 ± 1.96 mg GAE gE-1 DW after extrusion. Addition 20% of apple BPF increased TPC in crispbread to 193.92 ± 1.37, carrot BPF 171.36 ± 6.97 and pumpkin BPF to 195.09 ± 4.68 mg GAE gE-1 DW after extrusion. Antioxidant activity of control (20% oats, 80% rye flour blends) sample was 0.516 ± 0.192 mg TE gE-1 DW but in samples with addition of 20% by-products, it was significantly higher reaching 0.926 ± 0.05 TE gE-1 DW in samples with pumpkin by-products after extrusion.
Mostrar más [+] Menos [-]Response of barley on seaweed biostimulant application
2018
Szczepanek, M., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Jaskiewicz, B., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Kotwica, K., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
In some regions of the world, there is a risk of limiting crop production due to the growing pressure of biotic and abiotic factors. It is mostly connected with the forecasted climatic changes. Hence, alternative methods for supporting plant growth are sought for, and among them, biostimulants can play a significant role. The three-year (2009 – 2011) field experiment with spring barley (Hordeum vulgare L.) was conducted in Poland to assess the response of grain yield, yield components, as well as the content and uptake of N, P and K in grain to differentiated times and to a dose of seaweed (Ecklonia maxima Osbeck) biostimulant Kelpak application. Preparation was applied in a dose of 2 L haE-1 at BBCH 22 (early treatment) or in a dose of 2 L haE-1 at BBCH 31 (late treatment), as well as two times, 1.5 L haE-1 each, in both phases. The study indicated that the biostimulant had a favourable effect on the root weight, grain number per spike, thousand grain weight and seed yield in early treatment as compared with the control. Early application also had a positive effect on N and P uptake in the grain yield. Favourable response of barley to the application of biostimulant shows the usefulness of the seaweed extract in the cultivation technology of this crop.
Mostrar más [+] Menos [-]The effect of superabsorbent polymer application on yielding of winter wheat (Triticum aestivum L.)
2018
Grabinski, J., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Wyzinska, M., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland)
Superabsorbents are hydrophilic polymers that can absorb large amounts of water. These studies show that the use of superabsorbent may significantly reduce the negative effects of drought stress on plants. However, their use in the field cultivation has so far been minimal. The price of hydrogels has recently decreased significantly. This was the reason for starting research described in this work, in which the experimental plant was the winter wheat cultivar ‘Lucullus’ – the cereal which is the most intensively cultivated in Poland. The field experiment was conducted in the years of 2014 – 2016, in the Agricultural Experimental Station (AES) in Osiny, Poland, in 4 repetitions. TerrahydrogelAqua was evaluated in the following doses: 1) control without hydrogel, 2) 10, 3) 20 and 4) 30 kg•haE-1. Before harvesting, the plant samples were taken to determine the yield structure elements. After harvesting, grain yield at 15% moisture content was determined. The influence of hydrogel on winter wheat grain yield varied in individual years. On average, the yield of wheat grain from the treatment with a dose of 30 kg•haE-1 of hydrogel was significantly higher than from the control treatment or the treatment with a dose of 10 kg•haE-1 of hydrogel. The mean values of yield structure features, i. e. ear grain yield and weight of thousand grain were the highest at the dose of 30 kg•haE-1 of hydrogel. The effect of hydrogel on the average number of plants and ears per unit area and on the number of grains per ear was not found.
Mostrar más [+] Menos [-]Temporal variability of drought in field crops in the region of Kujawsko-Pomorskie, Poland
2018
Kusmierek-Tomaszewska, R., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Dudek, S., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Zarski, J., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Januszewska-Klapa, K., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
The objective of the work, carried out as part of research programme on current change of the regional climate, was to confirm the hypothesis about the increasing frequency and intensity of droughts in May and June in the region of Kujawsko-Pomorskie (central Poland) in the years 1981 – 2010. Furthermore, the aim was to confirm a significant relationship between indicators characterizing meteorological and agricultural droughts. Material for the research was the data from five meteorological measuring points located in the region. Atmospheric precipitation and air temperature in the period of high water needs of cereals and rapeseed (May–June) were used. Statistical methods widespread in climatological studies were applied, particularly the method of trends. The average multiannual totals (1981–2010) of rainfall in May–June allow ranking the region of Kujawsko-Pomorskie into the area of the lowest rainfall in Poland. The frequency of meteorological drought in May and June is 23.3–30.0% in the region. In the analysed period there were no significant changes in the frequency and intensity of these droughts with the passage of years. Rainfall shortages in cereal crops and rapeseed production range on average from -19 to -35 mm, and extend to maximum of -93 to -117 mm. The values of shortages did not show any significant changes in the years of the study. The significant dependence between the indicators of meteorological and agricultural droughts allows for determination of the rainfall shortages in crop production on the basis of the SPI values.
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