Nitrogen Fertilizer and Sewage Sludge Effects on Hybrid Poplars

摘要

The major objective of the project was to assess the impact of alternative sources of fertilizer on the growth of hybrid poplars. Interest in increasing the production of woody biomass for pulp, chips, fuel, and energy fuel stock has led to the cultivation of hybrid poplar in short-rotation intensive-cultivation systems. Hybrid poplars root easily from cuttings, grow quickly in the early stages of their life cycle, and can be coppiced. Species and varieties of poplars have been hybridized to produce clones that are adapted to a range of site conditions and are resistant to certain diseases. Highest biomass production is obtained under cultivated, fertilized, well-watered and well-drained conditions. Initial studies seem to indicate that poplar clones with larger root biomass can compete more effectively with weeds, and still increase nutrient and heavy metal uptake.