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Effect of wood ash as a nutrient rich production waste on the growth of silver birch in a cut-away peatland
No full textBakalaureusetöö
Metsanduse õppekavalPikaajalise turba kaevandamise tagajärjel on viimaste andmete järgi Eestis 9371 hektarit
mahajäetuid turbalasid, mis on oluliseks CO2 allikaks ning väga tuleohtlikud. Jääksoode
looduslik taastumine võtab aega aastakümneid. Selleks, et vähendada eralduva
süsihappegaasi kogust, tuleks jääksood taastada. Ökoloogilistest ja majanduslikest
aspektidest on jääksoode metsastamine üks perspektiivikamaid võimalusi.
Käesoleva töö eesmärgiks on hinnata erinevate puutuha koguste mõju arukase kasvule
Ulila ammendatud freesturbaväljal. Ulila katsealal mõõdeti 2022. aastal kaskede
kõrguskasvud ja juurekaela diameetrid ning võrreldi varasemalt (2009-2021) mõõdetud
puude kasvunäitajatega. Andmeid koguti kahelt katsevariandilt, millest esimest
katsevarianti oli töödeldud puutuha kogusega 5 t/ha ja teist kogusega 10 t/ha. Paremad
tulemused mõõdeti katsealalt, mida oli töödeldud suurema puutuha kogusega 10 t/ha. Nii
Soomes kui ka Eestis tehtud puutuha katsete tulemused olid sarnaseid Ulila katsealal
saadud tulemustega. Mõlemal puutuhaga töödeldud katsealal oli väga hästi näha, et
kaskede väetamine puutuhaga kiirendas oluliselt kaskede kasvu, kuna puutuha lisamisega
paraneb turba jääklasundis puude kasvuks oluliste P- ja K-sisaldus.As a result of long-term peat extraction, according to the latest data, there are 9371
hectares of abandoned peatlands in Estonia, which are an important source of CO2 and are
highly flammable. The natural recovery of cutaway peatlands takes decades. In order to
reduce the amount of carbon dioxide emitted, the cutaway peatlands should be restored.
From an ecological and economic point of view, the afforestation of cutaway peatlands is
one of the most promising options.
The aim of this work is to assess the impact of different quantities of wood ash on silver
birch growth in the exhausted cutaway peatland of Ulila. At the Ulila test area, in 2022,
the height growths and the root diameters of silver birches were measured and were
compared with previously measured (2009-2021) tree growth indicators. Data were
collected from two test variants, the first of which had been treated with a quantity of
wood ash of 5 t/ha and the second with a quantity of 10 t/ha. Better results were measured
from the test area, which had been treated with a higher amount of wood ash of 10t/ha.
The results of the wood ash tests carried out in Finland and Estonia were similar to those
obtained in the Ulila test area. In both test areas treated with wood ash, it was very clear
that fertilizing birches with wood ash significantly accelerated the growth of birch trees
because with the addition of wood ash the content of P and K which are important for tree
growth impruves in residual peat
The stimulating effect of wood ash on the growth of Silver birch in abandoned peatlands
No full textMagistritöö
Metsamajanduse ja metsaökoloogia õppekavalEestis on ligikaudu 10 000 ha jääksoid, mille looduslik taastumine on vaevaline ja aeganõudev. Jääksood emiteerivad suures kogustes CO2 ja on väga tuleohtlikud. Selleks, et vähendada jääksoodest tulenevaid keskkonnariske tuleks alad taastada. Üheks võimalikuks taastamisviisiks on jääksoode metsastamine toitainerikka puutuha abil.
Käesoleva töö eesmärk on hinnata erinevate puutuha koguste (5 t/ha, 8 t/ha, 10 t/ha ja 15 t/ha) mõju arukase (Betula pendula) kasvule ning analüüsida tulemusi koos ilmastiku ja turbakeemia andmetega. Eesmärgi täitmiseks mõõdeti arukaskede juurekaela diameetrid ja kõrguskasvud Ulila ja Pindi ammendatud freesturbaväljadel ning võrreldi neid varasemate aastate andmetega. Katsealadelt võeti ka turbaproovid, et uurida, kuidas mulda viidud toiteelemendid mõjutavad puude kasvunäitajaid. Ilmastikuandmete põhjal hinnati sademete ning keskmiste, maksimaalsete ja minimaalsete ja temperatuuride mõju puude kasvule.
Töö tulemused näitasid, et puutuhaga väetamine parandab märkimisväärselt puude kasvu mahajäetud turbaaladel. Mõlemal katsealal saadi parimad tulemused 10 t/ha puutuhaga töödeldud variantidel. Turbakeemia analüüs kinnitas, et puutuhaga lisatud toiteelemendid parandasid kasvutingimusi, muutes happelise ja toitainevaese turbamulla arukase kasvuks sobivamaks. Rohked sademed pärssisid üldiselt puude kasvu, samas kui kõik temperatuurinäitajad, eriti maksimaalsed temperatuurid, soodustasid puude kasvu.There are approximately 10,000 hectares of abandoned peatlands in Estonia, where natural regeneration is slow and time-consuming. These degraded peatlands emit large amounts of CO₂ and pose a significant fire risk. To reduce the environmental risks associated with such areas, restoration efforts are necessary. One potential method of restoration is afforestation using wood ash.
The aim of this study is to evaluate the effect of different wood ash application amounts (5 t/ha, 8 t/ha, 10 t/ha, and 15 t/ha) on the growth of silver birch (Betula pendula) and to analyze the results in conjunction with weather data and peat chemistry. To achieve this, root collar diameter and height growth of silver birch was measured in the extracted milled peat fields of Ulila and Pindi, and compared with data from previous years. Peat samples were also collected from the experimental sites to study how the added nutrients in the soil influenced tree growth indicators. Based on weather data, the effects of precipitation and average, maximum, and minimum temperatures on tree growth were assessed.
The results of the study showed that fertilization with wood ash significantly improves tree growth in abandoned peat areas. The best results at both test sites were achieved with the treatment of wood ash amount 10 t/ha. Peat chemistry analysis confirmed that the nutrients added through wood ash improved the growth conditions by making the acidic and nutrient-poor peat soil more suitable for silver birch. Heavy rainfall generally hindered tree growth, while all temperature indicators especially maximum temperatures had a positive effect on tree growth
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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