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Longer periods of drought and droughts of higher intensity are expected to become increasingly frequent with future climate change. This has implications for the microbially mediated turnover of soil organic matter (SOM), which will feedback to the global C cycle. In this study, we addressed the microbial dynamics underlying the pulse of respiration following rewetting of dry soil, and how the dro
We studied the microbial communities in maize (Zea mays) rhizosphere to determine the extent to which their structure, biomass, activity and growth were influenced by plant genotype (su1 and sh2 genes) and the addition of standard and high doses of different types of fertilizer (inorganic, raw manure and vermicompost). For this purpose, we sampled the rhizosphere of maize plants at harvest, and an
Cyanobacteria-plant symbioses play an important role in many ecosystems due to the fixation of atmospheric nitrogen (N) by the cyanobacterial symbiont. The ubiquitous feather moss Pleurozium schreberi (Brid.) Mitt. is colonized by cyanobacteria in boreal systems with low N deposition. Here, cyanobacteria fix substantial amounts of N-2 and represent a potential N source. The feather moss appears to
The fungal symbionts forming ectomycorrhizas, as well as their associated bacteria, benefit forest trees in a number of ways although the most important is enhancing soil nutrient mobilization and uptake. This is reciprocated by the allocation of carbohydrates by the tree to the fungus through the root interface, making the relationship a mutualistic association. Many field observations suggest th
Feather mosses utilize various sources of nitrogen (N): they absorb N deposited on leaf tissue, they host N-2 fixing cyanobacteria, and they are able to take up N directly from soil. In addition to their importance as primary producers in boreal ecosystems, feather mosses play a significant role in N cycling. However, estimates of their ability to take up N from soil in situ are scarce. Further, c
The effect of pH on the instantaneous growth of soil bacterial communities was studied in five soils with different pH (4.5-7.8) using leucine (Leu) and thymidine (TdR) incorporation. The pH dependency of bacterial growth was modelled using three different unimodal functions, and the pH(opt) for growth and the pH range in which growth was > 50% of the optimal growth were compared. Leu and TdR inco
Liming is used to counteract forest decline induced by soil acidification. It consists of Ca and Mg input to forest soil and not only restores tree mineral nutrition but also modifies the availability of nutrients in soil. Ectomycorrhizal (ECM) fungi are involved in mineral nutrient uptake by trees and can recover them through dissolution of mineral surface. Oxalate and siderophore secretion are c
Salinization of soil is recognised as one of the most pressing environmental challenges to resolve for the next century. We here conduct a synoptic review of the available research on how salt affects decomposer microbial communities and carbon (C) cycling in soil. After summarizing known physiological responses of microorganisms to salinity, we provide a brief overview and qualification of a sele
Archaea are ubiquitous in forest soils, but little is known about the factors regulating their abundance and distribution. Low molecular weight organic compounds represent an important energy source for archaea in marine environments, and it is reasonable to suspect that archaeal abundance is dependent on such compounds in soils as well, represented by, for example, plant and fungal exudates. To t
A more detailed mechanistic understanding of how low molecular weight (MW) carbon (C) substrates are mineralized within the rhizosphere by soil microbial communities is crucial to accurately model terrestrial C fluxes. Currently, most experiments regarding soil C dynamics are conducted ex-situ (laboratory) and can fail to account for key variables (e.g. temperature and soil water content) which va
Background: Array comparative genomic hybridization (aCGH) is commonly used to screen different types of genetic variation in humans and model species. Here, we performed aCGH using an oligonucleotide gene-expression array for a non-model species, the intertidal snail Littorina saxatilis. First, we tested what types of genetic variation can be detected by this method using direct re-sequencing and
Rewetting a dry soil can result in two response patterns of bacterial growth and respiration. In type 1, bacterial growth starts to increase linearly immediately upon rewetting and respiration rates are highest immediately upon rewetting. In type 2, bacterial growth starts to increase exponentially after a lag period with a secondary increase in respiration occurring at the start of the exponentia
To estimate the production of external ectomycorrhizal mycelia (EMM) in Norway spruce forests with varying nitrogen (N) and phosphorus (P) levels, and to relate this to the N retention capacity of ectomycorrhizal fungi (EMF) and N leaching. Seasonal changes in EMF production (in ingrowth mesh bags) and soil water N (in suction lysimeters) were analyzed after fertilization with N or N combined with
Clonal plants from poor habitats benefit less from morphologically plastic responses to heterogeneity than plants from more productive sites. In addition, physiological integration has been suggested to either increase or decrease the foraging efficiency of clonal plants. We tested the capacity for biomass production and morphological response in two closely related, rhizomatous species from habit
Theory predicts that variability in size and the shape of a morphological trait should often be stable both at the intra- and interspecific level. We studied variation in beak integration among several populations of two species of the genus Passer, a hybrid species, the Italian sparrow (Passer italiae) and one of its parents, the Spanish sparrow (Passer hispaniolensis). We show that the general s
Since the new integration policy from 1975 Swedish politics has been characterized as a multicultural society among scholars and others both in Sweden and abroad. The purpose of this thesis was to study the political debate around three minority practices (the Jewish and Muslim method of slaughtering animals, the veil and the turban, and religious and ethnic schools) to find out if the policy of t
This thesis explores the role of the architect in the construction process. The project involves designing, projecting, and constructing a 30-square-meter Attefall house in accordance with Swedish building regulations, where the architect assumes full responsibility from concept to completed building. By combining design and construction, the study investigates how the architect’s direct involveme
Purpose: This study aims to analyse how the founder as brand concept can affect Customer Based Brand Equity. The research aims to contribute insights on how founder representation can strengthen or weaken brand perception among consumers. Methodology: This research follows a quantitative, abductive design. Primary data were collected through a semi-structured focus group interview and secondary da
