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Bioactive compunds in raspberry fruit
No full textUurimistöö eesmärgiks on kirjanduse ja erinevate uurimustööde põhjal võrrelda erinevate
sortide ja säilitusviiside mõju vaarika viljades leiduvate olulisemate bioaktiivsete ühendite:
askorbiinhape, antotsüaanide ja ellagitanniinide sisaldusele. Töö hüpotees on: bioaktiivsete
ühendite sisaldust vaarika viljades mõjutavad sordiomadused ja säilitusviis.
Uurimistöö kirjanduslik ülevaade annab ülevaate vaarika botaanilisest kuuluvusest ja
bioloogilistest iseärasustest, vaarika biokeemilisest sisaldusest ning bioaktiivsetest ainetest
vaarika viljades. Kirjanduse ülevaatest selgus, et vaarikas on kõige olulisematest
bioaktiivseteks aineteks askorbiinhape, antotsüaanid ning ellagitanniinid ja elaaghape.
Materjali ja metoodika osas kirjeldab uurimustöid, kus uuriti askorbiinhappe,
antotsüaanide, ellagitanniinide ja elaaghappe sisaldust vaarika viljades ning nende
külmutamise ja säilitamise mõju neile. Materjali ja metoodika osa koostamiseks kasutati ISI
WEB OF KNOWLEDGE andmebaasi, valiti avaldamise aastateks 2000-2015 ning otsingu
märksõnad: raspberry cultivars and anthocyanins; raspberry cultivars and ellagitannins;
raspberry cultivars and ascorbic acid; effect of freezing and storage on anthocyanins,
ellagitannins and ascorbic acid. Materjali ja metoodika osa koostamiseks valiti välja 12
teadusartiklit. Uurimustöö tulemustest ja analüüsist selgus, et askorbiinhappe, antotsüaanide
ning ellagitanniinide ja elaaghappe sisaldust ning külmutamist ja säilitamist mõjutab eelkõige
vaarika sort. Vaarika viljade viljumisajal ja viljade värvil on bioaktiivsete ainete sisaldusele
väiksem, kuid olenevalt sordist individuaalne mõju.The aim of this bachelor thesis was to compare the effect of raspberry cultivars and different
storage techniques to the major bioactive compounds in raspberry fruit: ascorbic acid,
anthocyanins, ellagitannins and ellagic acid based on literature and research articles. The
hypothesis of the bachelor thesis was that the bioactive content of raspberry fruit is affected
by different cultivar characteristics and conservation techniques.
The literature part of the thesis gives an overview of raspberries botanical affiliation,
biological characterization content of biochemicals and bioactive compounds in raspberries.
In the literature overview the fact that ascorbic acid, anthocyanins, ellagitannins and ellagic
acid are the most important bioactive compounds in raspberries is stated.
The material and method part of the thesis describes research articles where the same
bioactive compunds and the effect of freezing and storaged were analysed. ISI WEB OF
KNOWLEDGE database was used for reasearching articles from years 2000-2015 searched
keywords were: raspberry cultivars and anthocyanins; raspberry cultivars and ellagitannins;
raspberry cultivars and ascorbic acid; effect of freezing and storage on anthocyanins,
ellagitannins and ascorbic acid and 12 appropriate research articles were chosen.
From the result of the research and analysis it can be stated that ascorbic acid,
anthocyanins, ellagitannins and ellagic acid contentand ellagic acids content and the effect of
freezing and storage of those bioactive compounds in raspberries is influenced mainly by
raspberry cultivar. The time of fruiting and the colour of raspberry fruits has a smaller but
individual effect (depending on the cultivar) to the bioactive content of raspberries
Anthropogenic influence on migration stopover site selection by spotted eagles
Full text linkMagistritöö
Linna- ja tööstusmaastike korralduse õppekavalTöö eesmärgiks on uurida millistes piirkondades konnakotkad rännetel peatuseid teevad, ning
kui palju on peatused mõjutatud inimasustuse poolt.
Konnakotkad on kaitsealused ligiid. Edukaks kaitse planeerimiseks oleks vaja teada millised
on kotkaste poolt eelistatavad peatuste piirkonnad.
Töös antakse asjakohane kirjanduse ülevaade lindude rändest, rändepeatuspaikadest ja
konnakotkastest. Andmed analüüsiks kogun rändekaartilt ja Google Earth Pro’st.
Tulemused näitavad, et enamus konnakotkaid teeb sügis- ja kevadrändel peatuseid. Peamiselt
peatutakse Euroopas. Keskmine kaugus suurematest linnadest on 7,4 km. Eeskätt peatuti
kultuurmaastikel.
Antud uurimust oleks vaja jätkata veel täpsemate andmete saamiseks.The aim of the work is to investigate in which areas spotted eagles use to stopover sites and
how human settlements affect them.
Spotted eagles are endangered species. For successful planning of protection, it is necessary
to know which areas eagles use to stopover sites.
In my work I give relevant literature overview of birds migration, migratory stopover sites
and spotted eagles. The data for the analysis is collected from Migration Card and Google
Earth Pro.
The results show that most of spotted eagles make stops on autumn and spring migration.
They mainly make stops in Europe. The average distance from larger cities is 7,4 km.
Primarily they were stopped on cultural landscapes.
This study need to be continued to provide even more accurate data
Breaking new ground: floristic diversity and conservation implications in Bordj Bou Arreridj Forests, Algeria
No full textReceived: July 29th, 2025 ; Accepted: November 27th, 2025 ; Published: December 3rd, 2025 ; Correspondence: [email protected] study assessed the floristic diversity and conservation status of two ecologically significant forests in Bordj Ghedir region, southeastern Bordj Bou Arreridj, Algeria: Ouled Hanneche (10,221.69 ha) and Ouled Khelouf (8,580.47 ha), covering a combined area of 18,802.16 hectares. Field inventories conducted in March 2023 across 13 stations, with 13 plots collected using random sampling methods. We identified 71 plant species from 32 families and 64 genera. The Asteraceae and Lamiaceae families were dominant. Hemicryptophytes and Therophytes were the most abundant life forms, and chorological analysis indicated a predominance of Mediterranean elements. Ecological indices (Shannon H' up to 3.602; Simpson 1-D up to 0.97) confirmed high species richness and diversity, particularly in the Ouled Hanneche forest. Despite this richness, the ecosystems face threats from overgrazing, wildfires, and insect pests. The findings provide a critical baseline for conservation and underscore the need for sustainable management strategies, including protected area enforcement and community engagement, to preserve this unique Mediterranean biodiversity hotspot
Effect of different date palm (Phoenix dactylifera) compost modalities on soil parameters in the Algerian Semi-Arid Zone
No full textReceived: August 22nd, 2025 ; Accepted: November 27th, 2025 ; Published: December 5th, 2025 ; Correspondence: [email protected] the vast regions of eastern Algeria, the calcareous soils are characterised by low fertility. Moreover, these soils frequently lack organic matter and essential nutrients, limiting sustainable yield potential. This study aimed to assess the impact of using locally sourced date palm compost with mineral fertilisers on the improvement of soil fertility in a cereal-based system. A field experiment was arranged in a randomised complete block design (RCBD) with 11 treatments: date palm compost applied at three rates (C1: 30 t ha⁻¹, C2: 50 t ha⁻¹, C3: 70 t ha⁻¹), either alone or combined with monoammonium phosphate (C1M, C2M, C3M: 100 kg ha⁻¹ MAP) or urea (C1U, C2U, C3U: 50 kg ha⁻¹ urea), one treatment with sheep manure at 45 t ha⁻¹, and an untreated control.. The study evaluated the effects of varying rates of date palm compost and mineral fertilisers on soil chemical characteristics at two depths (0–20 cm and 20–40 cm). Results indicated that elevated compost rates, whether applied alone or combined with mineral fertilisers, significantly improved organic matter content, nutrient availability, and soil chemical balance at both depths. Combined treatments C3U (70 t ha⁻¹ compost + 50 kg ha⁻¹ urea) and C3M (70 t ha⁻¹ compost + 100 kg ha⁻¹ MAP) showed the greatest improvements, with C3M identified as the optimal treatment. Integrated date palm compost fertilisation is well-suited to the region's calcareous soils, enhancing nutrient availability, improving soil fertility, and efficiently utilising a locally available resource. These findings suggest that integrating date palm compost with mineral fertilisers is a sustainable approche to improving soil fertility in semi-arid mediterranean systems
Estimating spring wheat nitrogen use efficiency via proximal and UAV sensing in Northwest Latvia
No full textReceived: September 19th, 2025 ; Accepted: November 27th, 2025 ; Published: December 4th, 2025 ; Correspondence: [email protected] nitrogen use efficiency (NUE) is labour-intensive and time-consuming, often requiring destructive biomass sampling. Cost-effective sensing tools provide a promising alternative for rapid assessment of numerous wheat genotypes. In this study, sixteen spring wheat genotypes were evaluated in Latvia over three consecutive years (2021–2023) under two nitrogen fertilization levels (N75 and N150) in a split-split-plot design with two replicates, totaling 64 plots. NUE consistently differed between N rates and was strongly influenced by year-specific environmental conditions, providing contrasting scenarios for testing sensing approaches. To capture this variation, two platforms were tested for spectral estimation of NUE: a low-cost proximal phenomobile equipped with an RGB sensor, and an unmanned aerial vehicle (UAV) with a multispectral sensor. Canopy reflectance was measured at three growth stages (tillering, flowering, and milk development) to calculate 8 proximal and 9 UAV-based visible-spectrum vegetation indices (VIs). Although relationships between VIs and NUE were environmentally dependent, significant and robust correlations were found. Proximal sensing generally provided stronger prediction models, with the Normalized Green-Red Difference Index (NGRDI) and Green Area Index (GA) consistently most predictive across years. The milk development stage (GS75) proved optimal for NUE estimation. Comparisons of NGRDI between platforms demonstrated their compatibility, though UAVs offer higher throughput for large-scale phenotyping. These findings highlight the potential of integrating agronomic evaluation with canopy reflectance traits to support breeding and precision nitrogen management
Pühajärv
No full textPhytoplankton biomass, diversity and abundance in samples collected from Lake Pühajärv during the period 1951-2000
Diazotrophic plant growth-promotion bacteria and sugarcane straw levels: Effects on sugarcane productivity and on soil enzymatic and microbiological activities
No full textReceived: August 19th, 2024 ; Accepted: January 21st, 2025 ; Published: March 11th, 2025 ; Corresponding author: [email protected] to the rising demand for bioenergy, a certain amount of sugarcane straw is often removed for ethanol production, but this practice may compromise health soil. In addition to the amount of straw, growing concern with the environment has made the use of diazotrophic plant-growth promotion bacteria (DPGPB) an alternative to the use of nitrogen fertilizers. A research was designed with the aim of evaluating the effect of different amounts of straw kept on the soil on soil microbial and enzymatic parameters and on sugarcane yield during the first ratoon. The field experiment was carried out in randomized blocks, using nitrogen fertilizer (NF) or DPGPB (BI), both with four straw levels. The parameters evaluated were: β-glucosidase (GA), urease (UR) and acid phosphatase (APA) activities, fluorescein diacetate activity, basal soil respiration, microbial biomass N, total C, total N and labile carbon. Responses were not obtained for various parameters with respect to the straw levels which was attributed to the short experimental period. In general, the evaluated parameters were always higher in the BI treatment, except for APA, which was lower in this treatment. This fact could be attributed to the greater capacity of the inoculated plants to make phosphorus available to the plants, which could reduce APA. The absence of a response for sugarcane yield between the NF and BI treatments demonstrates the beneficial effect of the bacteria in the inoculant in suppressing plants with adequate nitrogen contents. Greater yields were obtained for the L64 and L100 straw levels with no significant difference. This demonstrates the adequateness of removing part of the straw to produce second generation ethanol
Suurlaht
No full textPhytoplankton biomass, diversity and abundance in samples collected from Suurlaht during the period 1999 and 2000
Äntu lakes
No full textPhytoplankton biomass, diversity and abundance in samples collected from Äntu lakes during the period 1956-1995
Enhancing the use of water to use the manure treatment technology Plant 40 at Mangeni PM OÜ
No full textMagistritöö
Majandusarvestuse ja finantsjuhtimise õppekavalTänapäeval on oluline olla võimalik keskkonnasõbralik ja hoida enda ümber olevat keskkonda. Põllumajandussektor ja eriti loomakasvatus, sealhulgas piimakarjakasvatus, on üheks suuremaks keskkonnajalajälje tekitajaks, millele otsitakse lahendusi. Põhjavesi on oluline nii inimestele kui loomadele joogivee allikas. Põllumajandusettevõtted, mis tegelevad loomakasvatusega sõltuvad põhjaveest, mille varud on maailmas kriitilise piiri lävel. Sellest tulenevalt otsib ettevõtte Mangeni PM OÜ võimalusi, kuidas oma põhjavee tarvet vähendada, rakendades võimalikke tehnoloogilisi lahendusi, mis tagavad tõhusama veekasutuse ettevõttes. Magistritöö eesmärk on hinnata veekasutuse tõhustamise võimalusi ettevõttes Mangeni PM OÜ lägapuhastusjaama LWR Plant 40 kasutuselevõtul. Antud magistritöös kasutatakse andmeid, mis pärinevad ettevõtte Mangeni PM OÜ raamatupidamise andmebaasidest ja dokumentidest. Töö metoodina on kasutusel võrdlusanalüüs erinevate võimalike variantide võrdlemiseks. Peamiseks töö tulemuseks on, et veekasutus muutuks ettevõttes keskkonnasäästlikkuse aspektist 54,87% tõhusamaks, sest hinnanguliselt väheneks põhjavee tarve aastas 65 746,63 kuupmeetrit. Majanduslikus mõttes ei ole investeeringu tegemine LWR lägapuhastusjaama Plant 40 mõttekas, sest aastased kulud suureneksid 97 078,98 euro võrra võrreldes seniste tehtud kuludega põhjavee pumpamiseks 2024. aasta põhjal. Kui ettevõte teeks täieliku tasuvusanalüüsi, mis arvestab tahkete ja vedelate toitaineelementidest saadavate rahavogudega, siis saaks parema ülevaate lägapuhastusjaama Plant 40 majanduslikust tasuvusest. Magistritöö autori arvates on investeeringu tegemine veekasutuse tõhustamiseks keskkonnasäästlikust võtmest igati oma eesmärki ja ettevõtte suundumust täitev, sest kasutatakse ära tekkivaid jääkprodukte, mille tulemusel väheneb vajadus põhjavee tarbimise järele. Edaspidi võiks uurida väetiste asendamise võimalikkust süsteemist eraldatud taimetoiteelementide kasutamisel ehk teostada tuleks kogu LWR lägapuhastusjaama Plant 40 tasuvusanalüüs.Nowadays it is important to be as environmentally friendly as possible and to take care of the environment around you. The agricultural sector, and in particular livestock farming, including dairy farming, is one of the major environmental footprints to be addressed. Groundwater is an important source of drinking water for both humans and animals. Livestock farms depend on groundwater, the world’s critical water supply. Consequently, the company Mangeni PM OÜ is looking for ways to reduce its groundwater needs by implementing possible technological solutions that ensure more efficient water use in the company.
The aim of the Master’s thesis is to assess the possibilities of enhancing water use in the company Mangeni PM OÜ manure treatment technology LWR Plant 40. The thesis uses data from the accounting databases and documents of Mangeni PM OÜ. A benchmarking analysis is used as a working method to compare diferent possible variants.
The main result of the work is that the use of water would become 54,87% more efficient in terms of environmental sustainability in the company, as the estimated annual groundwater demand would be reduced by 65 746,63 cubic meters. From an economic point of view, the investment in the LWR manure treatment technology Plant 40 does not make sense, as the annual costs would increase by 97 078,98 euros compared to the current costs for pumping groundwater on the basis of 2024. A full cost-benefit analysis by the company, taking into account the cash flows from solid and liquid nutrients, would provide a better insight into the economic viability of the manure treatment technology Plant 40.
In the opinion of the author of the Master’s thesis, investing in the improvement of water use from an environmentally friendly point of view is entirely consistent with its purpose and the trend of the company, since the resulting residual products are used, which reduces the need for groundwater consumption. In the future, the possibility of substituting fertilizers using system separated nutrients could be examined, or a cost-benefit analysis of the entire LWR manure treatment technology Plant 40 should be carried out