Sökning: "carbon nitrogen ratio"

Visar resultat 16 - 20 av 73 avhandlingar innehållade orden carbon nitrogen ratio.

1. 16. Seagrasses and their epiphytes : Characterization of abundance and productivity in tropical seagrass beds

   Författare :Jacqueline Uku; Mats Björk; Beatriz Diez; Evamaria Koch; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Seagrass; epiphytes; cyanobacteria; prokaryotes; diversity; productivity; carbon utilization; buffer sensitivity; Biology; Biologi;

   Sammanfattning : Seagrass beds cover large intertidal and subtidal areas in coastal zones around the world and they are subjected to a wide variety of anthropogenic influences, such as nutrient enrichment due to sewage seepage. This study was undertaken to address specific questions focusing on whether near shore tropical seagrasses that receive a constant influx of groundwater nutrient inputs, would exhibit a higher productivity and to what extent epiphytic algae reflect the impacts of nutrient inputs. LÄS MER

3. 17. Peatland Bryophytes in a Changing Environment : Ecophysiological Traits and Ecosystem Function

   Författare :Gustaf Granath; Håkan Rydin; Joachim Strengbom; Steven K Rice; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; allometric scaling; chlorophyll fluorescence; competition; decomposition; flooding; mire; N concentration; nitrogen deposition; photosynthesis; succession; stoichiometry; Ecological Botany; Ekologisk botanik;

   Sammanfattning : Peatlands are peat forming ecosystems in which not fully decomposed plant material builds up the soil. The sequestration of carbon into peat is mainly associated with the bryophyte genus Sphagnum (peat mosses), which dominate and literally form most peatlands. LÄS MER

4. 18. The synthesis of chiral bidentate (N,N), (N,P) and (N,O) ligands and their use in metal-mediated asymmetric carbon-carbon bond formation

   Författare :Fredrik Johansson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis covers three projects based on the metal-mediated formation of new chiral centers in the prescence of chiral ligands. The first project, involving (N,N)- ligands, concerns the synthesis of some (C2-symmetric bis(aziridine) ligands and the use of these in the addition of organolithium reagents to N-aryl protected imines leading to enantioselectivities of up to 89%. LÄS MER

5. 19. Soil moisture conditions control nutrient accumulation, carbon storage and tree growth in boreal forest landscapes

   Författare :Johannes Larson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Forest and soil properties change across landscapes due to the complex interactions between various environmental factors. In many landscapes, topography exerts a major influence on the variation in soil moisture conditions, which in turn largely affects soil properties and processes. LÄS MER

7. 20. Chemical and Morphological Characterisation of Aerosol Particles in the Tropopause Region

   Författare :Hung Nguyen Ngoc; Kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CARIBIC; Physics; Singel particle analysis TEM and EFTEM; Carbon and Sulphur; Light element analysis; Aerosol sampler; Chemical Characterisation; Aerosol in the Tropopause Region; Nuclear physics; Technological sciences; Fysik; Teknik; Kärnfysik; Fysicumarkivet A:000;

   Sammanfattning : The aim of this work was to study atmospheric aerosols, focusing on the chemical composition, the morphology and the origin of the aerosol in the upper troposphere and lowermost stratosphere. An aerosol sampler was developed for this purpose. A new method for quantitative analysis of the major components of the aerosol, i.e. LÄS MER