Sökning: "Nutrient productivity"

Visar resultat 1 - 5 av 83 avhandlingar innehållade orden Nutrient productivity.

  1. 1. Herbivores influence nutrient cycling and plant nutrient uptake : insights from tundra ecosystems

    Författare :Hélène Barthelemy; Olofsson Johan; Ellen Dorrepaal; Ann Milbau; Gough Laura; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Reindeer grazing; large herbivores; nutrient cycling; plant nutrient uptake; soil nutrient availability; arctic plant ecology; soil microbial communities; 15N stable isotopes; plant-soil interactions; plant quality; dung and urine.; Environmental Science; miljövetenskap; biology; biologi;

    Sammanfattning : Reindeer appear to have strong positive effects on plant productivity and nutrient cycling in strongly nutrient-limited ecosystems. While the direct effects of grazing on vegetation composition have been intensively studied, much less is known about the indirect effect of grazing on plant-soil interactions. LÄS MER

  3. 2. Nutrient use strategies of plants of various life-forms in a subarctic environment : Nutrient conservation as an adaption to infertile habitats

    Författare :Rolf Lutz Eckstein; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Mean residence time; Nutrient productivity; Nutrient use efficiency; Plant strategies; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Plant performance in relation to limiting nutrients was analysed using the concept of nutrient use efficiency (NUE). NUE can be decomposed into (1) the nutrient productivity (aNP) and (2) the mean residence time (MRT). LÄS MER

  4. 3. The role of nutrients for stream ecosystem function in Arctic landscapes : drivers of productivity under environmental change

    Författare :Maria Myrstener; Ryan A. Sponseller; Reiner Giesler; Ann-Kristin Bergström; Tenna Riis; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nutrients; Stream; Arctic; Boreal; Primary productivity; Algae; Biofilm; Nutrient limitation; Nitrogen; Phosphorus;

    Sammanfattning : Arctic and sub-Arctic freshwaters are currently experiencing substantial ecosystem changes due to the effects of global warming. Global warming effects on these freshwaters include increasing water temperatures, altered hydrological patterns, shifts in riparian vegetation and changes in the export of nutrients and carbon from soils. LÄS MER

  5. 4. 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

  7. 5. Nutrient imbalance in Norway spruce

    Författare :Gunnar Thelin; Avdelningen för kemiteknik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Silviculture; Växtekologi; Plant ecology; nitrogen saturation; base saturation; pH; multiple limitation; deficiency; copper; boron; potassium; pollution; sustainability; conifers; forestry; forestry technology; Skogsvetenskap; skogsbruk; skogsteknik; Soil Science; agricultural hydrology; Lantbrukshydrologi; marklära;

    Sammanfattning : The studies presented in my thesis indicate that growing Norway spruce in monoculture does not constitute sustainable forest management in a high N and S deposition environment, such as in southern Sweden. The combination of N-induced high growth rates and leaching due to soil acidification causes soil reserves of nutrients to decrease. LÄS MER