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Identification of wet areas in agricultural lands using remote sensing data
2019
Stals, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Ivanovs, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Wet areas in agricultural lands are usually not fully or properly managed due to problematic accessibility by heavy machinery and are associated with lower crop yields. There are neither studies regarding spatial distribution of wet agricultural areas in Latvia nor large scale soil maps. Being aware of these wet areas, it would be possible to plan actions for effective management of these areas, starting with a scale of landscape. A geographic information system model could serve as an assistant for decision-making, such as, a direct support for the management of amelioration systems, change of land use and management patterns or granting support payments. Remote sensing data like Sentinel-2 satellite images and LiDAR (Light detecting and ranging) technology can be used to identify local wet areas. The focus of this article is to evaluate different remote sensing indices and methods that can be used to identify wet areas in agricultural lands using open access data and software. From 52 indices, which were analysed with soil moisture field measurements in 33 sample plots, only two of them showed statistical significance in linear regression model (p is less than 0.05): normalized height model in resolution of 25 meters (r2 =0.45) and visible blue spectral band in April (r2 =0.39). Results from this study help to focus on different aspects of remote sensing data usage and methodology for future improvements in order to fully implement LiDAR and Sentinel-2 data for identification of wet areas in agricultural lands.
显示更多 [+] 显示较少 [-]Analysis of different approaches to real estate appraisal
2019
Surgelas, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Arhipova, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pukite, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The traditional valuation of real estate in the field of civil engineering did not include the uncertainty of human behaviour, which cannot be explained by the traditional approach. There are different valuation methods for real estate appraisal, which are basically classified into three groups as a classic, statistical and advanced. In this article, we estimated the different housing price models using the sample of 37 residential apartments in Riga, Latvia, October 2018. In order to evaluate if there is a possible association between the variables involved in relation to the property price, the analytical data were analysed by correlation analysis, analysis of variance (ANOVA), regression analysis, covariance analysis (ANCOVA), principal component analysis (PCA) and cluster analysis. The models estimation results show that using ANCOVA models for the prices forecasting the model fitting to data is less than 58%. The preliminary results of this study suggest that the estimated properties can be distributed in 4 groups, depending on number of rooms, area and age. In addition, the decision tree was created based on algorithms (J48) and a preliminary definition of the best rules was made. The decision tree presents an accuracy of 84% with 31 accepted instances for a total of 37 currently classified instances.
显示更多 [+] 显示较少 [-]Geoparks in cultural and landscape preservation context
2019
Porshnov, D., University of Latvia, Riga (Latvia) | Burlakovs, J., University of Latvia, Riga (Latvia);Linnaeus Univ. (Sweden);Estonian Univ. of Life Sciences, Tartu (Estonia) | Kriipsalu, M., University of Latvia, Riga (Latvia);Estonian Univ. of Life Sciences, Tartu (Estonia) | Pilecka, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Grinfelde, I. [and two others], Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Society aims to develop frames for recognizing important geological and geomorphological sites and features or landscapes within their national and even transnational boundaries. Earth heritage sites educate the general public and preserve cultural and environmental matters. New trends of sustainable development, importance of site conservation are demanding that landforms and landscapes, rocks, minerals, fossils, soils should be protected legally, as they give understanding about the evolution of Mother Earth in local and regional context to generations. The Geopark concept was developed in cooperation with UNESCO and followed a large number of requests to UNESCO from all over the world, from geological institutions and geoscientists and non-governmental organizations, and it became extremely popular and influential to preserve those geological heritage areas, nowadays still recognized only nationally or not at all. This paper aims to give comprehensive overview of existing geoparks in the Baltic Sea Region, as well as analyse aspiring geoparks and unpublished initiatives of potential geopark (Livonia and Vooremaa) eventual establishment in frames of cultural and landscape preservation context. Criteria, requirements and earlier studies are given in context. The geoparks should mainly contain cultural and educational purpose while targeting the least possible damage in preservational aspect.
显示更多 [+] 显示较少 [-]The pig feeding and nitrogen associated gaseous emissions in Latvia
2019
Frolova, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Degola, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Berzina, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The research paper focuses on description of the pig (Sus scrofa domestica) farming tendencies in Latvia with the scope to give feeding characteristics in relation to emission outcome. In the recent years the concentration of pigs in farms with a herd size more than 10,000 has increased. With increase of the large farms the average feed consumption is more affected by one operator. Efficient utilization of nutrients content in feeding is crucial to meet environmental goals. It is one of the steps to achieve Nutrient Use Efficiency. There is relationship between crude protein and reduction of reactive nitrogen. Feed content not only affects excreted nitrogen, but also pH of manure and total ammonia Cal nitrogen. It is complex abatement measure to quantify reduction of the emission because of impact of various environmental factors. In Latvia, the most common are sows cross breeds (Yorkshire × Landrace) and on January 1, 2019 the biggest group accounted was fattening pigs with average dry feed consumption per day from 0.33 kg (live weight from 5 to 6 kg) up to 3.6 kg (live weight from 80 to 120 kg) with crude protein value from 163.5 g to 155.3 g per 1 kg feed dry matter. Excreted nitrogen (Nex) was calculated for these groups of pigs less than suggested values in guidelines for emission calculation. The highest calculated total NH3 emission is from fattening pigs group with live weight from 55 to 90 kg although the highest calculated Nex is for lactating sows. NOx also calculates as NO2 and the highest value was 3.23 g per one lactating sow.
显示更多 [+] 显示较少 [-]Evaluation of a headspace solid–phase microextraction with different fibres for volatile compound determination in specialty coffee brews
2019
Laukaleja, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aroma of coffee is the main quality factor. Compounds with floral, fruity, citrus and sometimes fermented aroma notes are defined as high quality characteristics for the specialty coffee brew. Commercial coffees mostly are at medium roast and the aroma profile is focused on balanced chocolate, caramel, toasted bread and almond bitterness aroma notes. These sensory characteristics set the focus for volatile compound profile analysis by Headspace solidphase microextraction (HS-SPME). The most popular fibres for commercial coffee aroma profile analysis are DVB/ CAR/PDMS, CAR/PDMS, PDMS/DVB and PA. There is limited research done about specialty coffee aroma profile and evaluation of more suitable fibres for solid-phase microextraction. The aim of the research is to evaluate the aroma composition of specialty coffee brews using different SPME fibres. Results demonstrated that CAR/PDMS fibre, compared to other fibres, can extract significantly more volatile compounds with higher peak areas in all chemical compound groups, except phenols. The CAR/PDMS was the only fibre which could detect all 17 important volatile compounds for specialty coffee. In conclusion, from the given research evidence, CAR/PDMS fibre is suggested as the most suitable SPME fibre coating for volatile compound extraction for specialty coffee brew import. The result provides evidence for improved specialty coffee aroma profile analysis by SPME.
显示更多 [+] 显示较少 [-]Determination of organic acids in honey samples from Latvian market by high-performance liquid chromatography
2019
Keke, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Determination of organic acids in honey samples from Latvian market by high-performance liquid chromatography Honey is a naturally sweet product, which is produced by honeybees (Apis mellifera). Honey is a natural source of antioxidants and has been known to mankind since ancient times. Honey contains approximately 200 different compounds. Organic acids can be used as an indicator to detect the freshness, authenticity and acidity of honey. The aim of this research was to determine and quantify organic acids such as oxalic, L-tartaric, D-quinic, L-malic, L-ascorbic, citric, fumaric and succinic in honey samples from Latvian market u sing high-performance liquid chromatography. The chromatographic separation of organic acids was carried out with PerkinElmer C18 (4.6 mm Í 250 mm I.D, particle size 5 mm) analytical column at the temperature of 35 °C in wavelength at 210 nm. The obtained results showed that the analysed honey samples contain L-tartaric, D-quinic, L-malic, L-ascorbic, citric, fumaric and succinic acids. The concentration of these acids was found to be variable. Oxalic acid was not detected in the analysed honey samples. L-tartaric acid was the main acid in all analysed honey samples.
显示更多 [+] 显示较少 [-]Health status of gene fond donor cows of Latvian native breeds Latvian Brown and Latvian Blue
2019
Ringa-Karahona, G., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Sematovica, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Antane, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Mangale, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The preservation of local animal breeds is a topical theme in recent years. Latvian Brown (LB) and Latvian Blue (LZ) cow breeds are exhausting and must be preserved. It can be performed by the use of multiple ovulation and embryo transfer (MOET). The difficulties exist in choosing the gene-fond (GF) cows as donors caused by the small number of animals. Twenty-three cows were intended for donor cow’s role from different herds until September 2018, and twenty of them were accepted. Anamnesis, clinical examination, blood morphology (13 parameters) and biochemical indices (19 parameters) were analysed before MO induction. Three cows were rejected because of ovarian cysts or pyometra, negative energy balance (NEB) (glucose is less than 2.3 mmol LE−1 simultaneously with elevated ß-hydroxybutyric acid is greater than 1.4 mmol LE−1) and elevated (p is less than 0.05) number of leukocytes (28.20 x109 LE−1). More than 52.6% of cows had a repeated artificial insemination before the last parturition, and 5.3% of cows had lifeless offspring in the last parturition. The 1st and 2nd lactation cows were healthier than older cows (p is less than 0.05). The amount of albumins, cholesterol, triglycerides and Na, K, P, Cl, Mg was significantly different in donors with and without successfully obtained embryos (p is less than 0.05). In conclusion, not only acceptable clinical health but also the cow metabolic status is a decisive factor for success of MOET.
显示更多 [+] 显示较少 [-]Stem cell therapy in the treatment of bilateral elbow joint osteoarthritis in dog
2019
Skangals, U., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ilgazs, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of this pilot study was to assess whether a single mesenchymal stem cell intra-articular injection in the osteoarthritic joint gives a therapeutic effect. This trial study was made in order to better manage and structure further study on more dogs. Single injections of 3 million mesenchymal stem cell intra-articular injections were made bilaterally in the osteoarthritic elbow joints. The dog was examined before and after monthly stem cell therapy using stance analyser scales to determine the static weight of each limb. Weight balance between forelegs improved, but not significantly (p is greater than 0.05). A radiographic examination was made for both elbow joints before stem cell therapy and the second and fifth month thereafter. Calculations of sub-trochlear sclerosis in percentage were made using mediolateral projections. Sub-trochlear sclerosis in percentage significantly decreased (p is less than 0.05) after stem cell therapy in both legs.
显示更多 [+] 显示较少 [-]Thermographic skin evaluation after the use of electrosurgical devices and scalpel made incisions in rabbits
2019
Gatina, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ilgazs, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Berzina, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The purpose of using electrosurgical devices in veterinary practice is to reduce bleeding during the cut increasing temperature locally, causing coagulation and apoptosis of proteins. There is a lack of data on the extent and depth of these thermal damages and whether these effects on the different tissues are the same. Because of that, the aim of this study was to investigate which of the different electrosurgical devices causes highest heating effect on the skin tissue of rabbits (Oryctolagus cuniculus). The research was carried out at the Latvia University of Life Sciences and Technologies, Faculty of Veterinary Medicine. It included 50 rabbits, on average 2 years old, clinically healthy, with similar weight and condition. We formed five experimental groups: skin tissue cut with CO2 laser (n=10), an electrocoagulator (n=10), a tissue welding device (n=10), a radiofrequency apparatus (n=10) and a scalpel as control group (n=10). In order to evaluate the thermal effects of electrosurgical instruments on tissues, we performed contactless thermography. There were taken 3 images for each animal, totally 150 skin thermo-grams. From the obtained results we conclude that the most pronounced thermal effect on rabbit’s skin was caused with laser and an electrocoagulator. All electrosurgical devices caused a significantly higher (p is less than 0.01) increase in skin temperature compared to a surgical scalpel at the moment of tissue incision. During the study, it was found that the gentlest electrosurgical devices were used on rabbit skin tissue were a radiofrequency device.
显示更多 [+] 显示较少 [-]The economic impacts of the 2013 reform on the Hungarian agriculture
2019
Mizik, T., Corvinus Univ. of Budapest (Hungary)
The impacts of agricultural policies are decisive on the agricultural sector, especially in the case of the European Union’s (EU) Common Agricultural Policy (CAP). The 2013 CAP reform introduced several new measures. In budgetary terms, basic payment and greening were the most significant ones. Besides, coupled supports, young farmer and small farmers scheme should be mentioned. To reveal the changes caused by these measures, the time horizon of the study is 2013−2017. Since the subsidies represent a significant part of the income generated in the agricultural sector, the basic hypothesis of the study is that the production units concerned (individual farms, private enterprises) gave economically rational answers. In practice, this means trying to fully adapt to the changes to maximize support. Based on the analysed datasets (Hungarian Central Statistical Office and Hungarian State Treasury), it became evident that farmers responded rationally: splitting up farms against capping, moving towards the lowest resistance to comply with greening, plus associating them with the extra support of coupled payments. Generational renewal is a key issue; however, the present form of young farmers’ scheme needs to be refined to be more effective. Small farmers scheme is a good opportunity for farmers with less than 5.5 ha and most of the concerned farmers chose well. However, there are about 6,000 farms that are too small for the standard system, while 772 farms that are too large for the small farmers scheme.
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