Sökning: "microbial time series"

Visar resultat 11 - 15 av 17 avhandlingar innehållade orden microbial time series.

1. 11. Size and dynamics of active soil organic matter fraction as influenced by soil management

   Författare :Torben Bonde; Linköpings universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

   Sammanfattning : The determination of what has been termed an "active fraction" of soil organic matter (SOM) and the effect of management on the size and turnover of this fraction are the leading themes in the present thesis. The techniques employed to study the amount and turnover of this fraction include: long-term mineralization-incubations for determination of potentially mineralizable carbon (Co) and nitrogen (No), fumigation-incubation for determination of microbial biomass-C and N, and istotope techniques using 13C and 15N for determination of the dynamics of soil C and N. LÄS MER

3. 12. Ecosystem functioning in streams : Disentangling the roles of biodiversity, stoichiometry, and anthropogenic drivers

   Författare :André Frainer; Roland Jansson; Brendan McKie; Jonathan Benstead; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; detrital food web; functional diversity; stoichiometry; nitrogen and phosphorus concentrations; recalcitrant carbon; spatial and temporal species distribution; pools and riffles; isotopes; leaf decomposition rates; land use; restoration; habitat complexity;

   Sammanfattning : What will happen to ecosystems if species continue to go extinct at the high rates seen today? Although ecosystems are often threatened by a myriad of physical or chemical stressors, recent evidence has suggested that the loss of species may have impacts on the functions and services of ecosystems that equal or exceed other major environmental disturbances. The underlying causes that link species diversity to ecosystem functioning include species niche complementarity, facilitative interactions, or selection effects, which cause process rates to be enhanced in more diverse communities. LÄS MER

4. 13. Non-cyanobacterial nitrogen fixation insights in humic freshwater lakes and ponds

   Författare :Leyden Fernandez-Vidal; Stefan Bertilsson; Sari Peura; David Walsh; Uppsala universitet; []
   Nyckelord :humic lakes; thaw ponds; non-cyanobacterial diazotrophs; nitrogen fixation; nitrogenase;

   Sammanfattning : The biological basis of nitrogen fixation beyond the canonical role of Cyanobacteria is not well understood in freshwater ecosystems. To address this gap in knowledge, the main objective of this thesis is to study non-cyanobacterial nitrogen fixation in freshwater lakes and ponds. LÄS MER

5. 14. SOUnd-DRIven BIOtechnology

   Författare :Nasim Najjarzadeh; Paul Christakopoulos; Cristhian Álvaro Carrasco Villanueva; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biokemisk processteknik; Biochemical Process Engineering;

   Sammanfattning : Ultrasound has been vastly applied in different areas such as medical imaging and the food industry, but not much attempt has been made to investigate its influence on microorganisms and its potential to be applied in microbial biotechnology. Previous studies show the potential of acoustic waves to increase biomass yield, production of secondary metabolites and enhanced enzyme-catalyzed reactions, probably due to improved mass transfer and cell retention. LÄS MER

7. 15. Instrumentation, Control and Automation in Anaerobic Digestion

   Författare :Jing Liu; Bioteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bioteknik; Biotechnology; ICA; automation; control; monitoring; biosensor; instrumentation; anaerobic digestion; biogas;

   Sammanfattning : Anaerobic digestion (AD) is a biochemical process in nature. It has been used to decompose organic waste in order to reduce environmental pollution, and to destroy pathogenic microorganisms for the protection of human and animal health. The process itself produces methane, which can then be used as an energy source. LÄS MER