Sökning: "phosphorus nitrogen"

Visar resultat 1 - 5 av 149 avhandlingar innehållade orden phosphorus nitrogen.

  1. 1. The Story of Phosphorus : Sustainability implications of global phosphorus scarcity for food security

    Författare :Dana Cordell; Stuart White; Jan-Olof Drangert; Julie Wilk; Johan Rockström; Linköpings universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; global phosphorus scarcity; peak phosphorus; global food security; sustainable resource use; food production and consumption system; transdisciplinary; systems thinking; global fosforbrist; peak fosfor; global matsäkerhet; hållbar resursanvändning; system för produktion och konsumtion av mat; transdisciplinaritet; systemtänkande; Water in nature and society; Vatten i natur och samhälle;

    Sammanfattning : The story of phosphorus began with the search for the philosopher’s stone, and centuries later the critical role of phosphorus in soil fertility and crop growth was highlighted. Eventually, phosphorus was implicated in the global environmental challenge of eutrophication. LÄS MER

  2. 2. Microalgae for Phosphorus Removal from Wastewater in a Nordic Climate

    Författare :Karin Larsdotter; Gunnel Dalhammar; Jörgen Hanaeus; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; assimilation; hydroponics; light; microalgae; nitrogen; phosphorus; plants; precipitation; wastewater treatment; Bioengineering; Bioteknik;

    Sammanfattning : As part of a research project aiming to develop and evaluate a hydroponic system for wastewater treatment in Sweden, extended nutrient removal by microalgae was tested. The hydroponic/microalgal wastewater treatment system was built in a greenhouse in order to improve growth conditions for plants and algae. LÄS MER

  3. 3. Epiphytic lichen responses to nitrogen deposition

    Författare :Otilia Johansson; Kristin Palmqvist; Johan Olofsson; Annika Nordin; Lars E Ericson; Peter Crittenden; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Lichens; air pollution; nitrogen deposition; phosphorus; growth; chlorophyll a; boreal forest; field experiment; irrigation; carbon based secondary compounds; Lavar; luftföroreningar; alg; svamp; kväve; fosfor; skog; Terrestrial ecology; Terrestrisk ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Nitrogen (N) deposition has increased globally over the last 150 years and further increase is predicted for the future. Nitrogen is an important nutrient for lichens, involved in many processes in both photobiont and mycobiont.  However, N can be a stressor, causing many lichens and lichen communities to disappear with increased deposition. LÄS MER

  4. 4. Nutrient cycling in agroecosystems: nitrogen cycling in southern Sweden in the 1850s and two Tanzanian villages in the 1990s

    Författare :Lars-Erik Williams; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; nutrient; nutrient model; nutrient cycling; nitrogen fixation; nitrogen budget; mixed system; miombo; manure; livestock; land use; historical system; food production; efficiency; crops; agroecosystem; carrying capacity; phosphorus; Scania; sustainability; Plant ecology; Växtekologi;

    Sammanfattning : This study presents a general model for analysing nutrient cycling in agroecosystems. The focus is on food production intensity, human carrying capacity, sustainability and efficiency. The model can be used on systems including different kinds of land uses, which makes it applicable for studies on different scales. LÄS MER

  5. 5. Nutrient recovery from waste streams through struvite formation

    Författare :Maryam Latifian; Bioteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; struvite; nutrient; phosphorus; nitrogen; wastewater treatment; anaerobic digestion; urine;

    Sammanfattning : Eutrophication or the nutrient enrichment of water bodies, typically by nitrogen and phosphorus has adversely affected the aquatic life and the quality of water. Governments have been forced to take actions in order to reduce the release of these nutrients into the environment. LÄS MER