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Visar resultat 11 - 15 av 66 avhandlingar som matchar ovanstående sökkriterier.
11. Soil salinity as a driver of microbial community structure and functioning
Sammanfattning : Soil salinization is a pressing agricultural problem in many areas of the world, particularly in areas heavily reliant on irrigation agriculture. While the negative effects of salinity on crop plants have been widely studied, its effects on soil microorganisms have received less attention, and the impact of soil salinity on both microbial community structure and functioning is not well understood. LÄS MER
12. Effects of inorganic nitrogen and organic carbon on pelagic food webs in boreal lakes
Sammanfattning : Anthropogenic activities are increasing inorganic nitrogen (N) loadings to lakes in the northern hemisphere. In many boreal lakes phytoplankton are N limited, wherefore enhanced N input may affect the productivity of pelagic food webs. LÄS MER
13. Consequences of bushmeat hunting in tropical forests
Sammanfattning : This thesis evaluates the effect of bushmeat hunting in southeastern Nigerian rainforests on: 1) adult tree, seedling, and animal community compositions 2) germination and survival among seedlings in association with competition 3) changes in community composition at multiple trophic levels 4) leaf nitrogen concentration (LNC), leaf mass per area (LMA) and stem specific density (SSD) 5) on human reliance on forest resources and rural people use forest resources. Data for the first four evaluations were obtained from surveys, manipulative experiments in seedling plots and collected leaf samples in three pairs of sites with high (hunted sites) and low (protected sites) hunting pressure but with similar adult tree composition. LÄS MER
14. Ecological succession of benthic macrofauna following disturbance : Effects of contaminants and in situ sediment remediation
Sammanfattning : More than 70% of the Earth is covered by water, and most of the sea floor consists of soft sediments, such as mud, clay and sand. Thus, soft sediments form one of the most important habitats on Earth, with a high diversity of organisms. LÄS MER
15. Bacterial and fungal growth in soil: The effect of temperature and substrate addition
Sammanfattning : Bacteria and fungi are the main agents in decomposition of soil organic matter. Their activity is determined by the availability and quality of substrate, especially its content of carbon, but also nitrogen and phosphorus. Other environmental factors, which affect the activity of the microbial community in soil, are temperature, moisture and pH. LÄS MER
