Biomass and nitrogen dynamics in an irrigated hybrid poplar plantation

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:6258092

McLaughlin, R A

A 3-year study measured the effects of ground cover treatments and nitrogen fertilization on biomass and nitrogen dynamics in an irrigated hybrid poplar (Populus deltoides Bartr. x P. trichocarpa Torr. and Gray, clone NC-9922) plantation in northern Wisconsin. Annually fertilized (112 kg N/ha/yr) and unfertilized plots were either maintained weed-free (bare soil), allowed to revegetate with native weeds, or seeded to birdsfoot trefoil (Lotus corniculatus L.). Trees in bare soil plots responded to fertilization primarily in the third growing season, but total biomass of 3-year-old trees was not increased by annual fertilization. High nitrate-nitrogen concentrations in the soil solution suggested significant leaching in both unfertilized and fertilized bare soil plots in the first growing season, and in fertilized plots the second season. Nitrate-nitrogen concentrations declined sharply in fertilized bare soil plots during the third growing season. Cover crop biomass was greatest in the second year and declined thereafter due to declines in below-ground components. Fertilization increased tree growth in these plots, but cover crop treatments had no effect. Results of this study suggest that, under irrigated conditions, a cover crop can substantially reduce leaching losses of nutrients and serve as a slow-release pool of nitrogen after the trees achieve crown closure. Fertilization is not recommended in these plantations until the second growing season if a cover crop is present and the third growing season if complete weed control is practiced.

• Research Organization: Purdue Univ., Lafayette, IN (USA)
• OSTI ID: 6258092
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
140504* -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
BIOMASS PLANTATIONS
CULTIVATION TECHNIQUES
DISSOLUTION
ECOLOGICAL CONCENTRATION
ELEMENTS
FEDERAL REGION V
FERTILIZERS
GROUND COVER
GROWTH
IRRIGATION
LEACHING
MINERALIZATION
NITROGEN
NONMETALS
NORTH AMERICA
PLANT GROWTH
PLANTS
POPLARS
SEPARATION PROCESSES
TREES
USA
WISCONSIN