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Now showing items 1-10 of 22
Dissertation

Litter quality, temperature, and soil water content as drivers of decomposition and respiration in a long-term tillage trial
(2019-08)
For sugar beet cultivation in most parts of central Europe especially water erosion is a serious problem, as for in the beginning of the growing season in late spring inherent to the cultivation system large soil areas of bare soil are left poorly protected up to the time when the plants are closing in the rows (beginning of crop covering; phenological growth stages of BBCH 31 - 39) (Koch et al., 2009). Non-inversion tillage systems are an effective measure for reducing erosion risks by diminishing soil compaction ...
Dissertation

Effects of climate change on fungal community structure and organic matter turnover in soil profiles along elevation gradients in alpine ecosystems
(2019-10)
Although elevation patterns of diversity for plants and animals are well known, understanding of variations in fungal community structure along elevation gradients is limited. Soil fungi play an important role in soil microbial communities, where they improve soil organic matter (SOM) turnover and nutrient circulation. Hence, any change in fungal community structure will have strong effects on soil and ecosystem functioning. The main purpose of this thesis is therefore to investigate how climate induced shifts in ...
Dissertation
Studies on arbuscular mycorrhiza (AM) in the Alentejo (Portugal) using pea mutants resistant to AM fungi as a control tool for field conditions
(2002-09-20)
The utilization and management of arbuscular mycorrhiza (AM) symbiosis may improve production and sustainability of the cropping system. For this purpose, native AM fungi (AMF) were sought and tested for their efficiency to increase plant growth by enhanced P uptake and by alleviation of drought stress. Pot experiments with safflower (Carthamus tinctorius) and pea (Pisum sativum) in five soils (mostly sandy loamy Luvisols) and field experiments with peas were carried out during three years at four different sites. ...
Dissertation
Mikrobielle Nutzung von Ernteresten in Bodensäulen und Litterbags
(2009)
Die vorliegende Arbeit untersuchte die Einflüsse der Bodenart und Einarbeitungstiefe von Streu auf die mikrobielle Nutzung und ihren Abbau. Anhand einer Kohlenstoffsequestrierung wurde die Verlagerung streubürtigen Kohlenstoffes in die Fraktionen CO2-C, SOC, extrahierbaren Kohlenstoff, Cmik und POM-C betrachtet. Aufgrund der Analyse der δ13C-CO2 Werte der Bodenrespiration, im Rahmen der Sequestrierung des streubürtigen Kohlenstoffes, war der Anteil der streubürtigen Bodenrespiration und somit die gesamte, zu erwartende ...
Dissertation
Effects of grassland conversion and tillage intensities on soil microbial biomass, residues and community structure
(2013-09-23)
Agricultural intensification has a strong impact on level of soil organic matter (SOM), microbial biomass stocks and microbial community structure in agro-ecosystems. The size of the microbial necromass C pool could be about 40 times that of the living microbial biomass C pool in soils. Due to the specificity, amino sugar analysis gives more important information on the relative contribution of fungal and bacterial residues to C sequestration potential of soils. Meanwhile, the relationship between microbial biomass ...
Dissertation
Auswirkung der Rückführung von Kurzumtriebsplantagen in Acker- und Grünlandnutzung auf Boden C-Fraktionen
(2013-04-05)
Bei der Rückführung von Kurzumtriebsplantagen (KUP) in konventionelle landwirtschaftliche Nutzung erfolgt zur Saatbettvorbereitung für die Folgekulturen eine intensive Bodenbearbeitung, um Wurzeln und Erntereste zu zerkleinern und in den Boden einzuarbeiten. Dies erhöht einerseits die Mineralisierung der unter KUP akkumulierten organischen Bodensubstanz (OBS), andererseits werden dem Boden hohe Mengen an Kohlenstoff (C) mit den Ernteresten zugeführt. In dieser Arbeit wurde an den Standorten Georgenhof Pappel, ...
Dissertation
Salinity-induced changes in the microbial use of sugarcane filter cake added to soil
(2008-02-27)
Five laboratory incubation experiments were carried out to assess the salinity-induced changes in the microbial use of sugarcane filter cake added to soil. The first laboratory experiment was carried out to prove the hypothesis that the lower content of fungal biomass in a saline soil reduces the decomposition of a complex organic substrate in comparison to a non-saline soil under acidic conditions. Three different rates (0.5, 1.0, and 2.0%) of sugarcane filter cake were added to both soils and incubated for 63 days ...
Dissertation
Der Einfluss organischer Düngung auf die mikrobielle Biomasse und deren Residuen in unterschiedlichen Nutzungssystemen
(2013-10-23)
Die Gabe von organischem Dünger beeinflusst die Menge und die Zusammensetzung der organischen Substanz im landwirtschaftlich genutzten Boden. Dies wirkt sich auch auf den Umfang der mikrobiellen Biomasse im Boden und ihrer Gemeinschaftsstruktur aus.
Diese Arbeit beschäftigte sich mit der Untersuchung von mineralischer und organischer Düngung auf die der mikrobiellen Gemeinschaft im Oberboden, Unterboden und unter subtropischen Bedingungen. Der Fokus der Arbeit lag zum einen in der Bestimmung der physiologischen ...
Dissertation

Tree Vigour in Apple Production: Impact of Replant Disease and Mitigation Strategies
(2022)
Cultivating apples on sites previously used for cultivation of apples leads to suppression of vegetative performance of apple trees and losses in fruit yields. This replant effect is attributed to an apple related form of soil fertility loss named ‘soil fatigue’ and ‘Apple Replant Disease’ (ARD). Replant disease strongly affects profitability of apple production in nurseries specialised in fruit trees, as well as on fruit orchards. Recent studies focus on causally linked agents of the replant disease and quantification ...
Dissertation
Interactions of organic amendments, pea (Pisum sativum L.) growth, arbuscular mycorrhizal fungi and other soil microorganisms
(2017-07-25)
Microbial decomposition of organic substances in soil is a central process for maintaining nutrient cycling, and it can be affected by the presence of plants, especially by mycorrhizal plants, in different ways. Organic fertilizers maintain soil fertility and increase crop productivity. Less attention has been paid to C-rich organic fertilizers. On the other hand, legumes are the main source of N input in organic farming. However, field peas grown as a sole crop suffer many problems that make the yield low and ...