Studies on household energy use generally focus on social and psychological factors influencing the acceptability of energy-saving measures. However, the influence of physical characteristics of energy-saving measures on their acceptability is largely ignored. In this study, preferences for different types of energy-saving measures were examined, by using an additive part-worth function conjoint analysis. Energy-saving measures differed in the domain of energy savings (measures aimed at home energy savings versus measures aimed at transport energy savings), energy-saving strategy (technical improvements, different use of products, and shifts in consumption), and the amount of energy savings (small versus large energy savings). Energy-saving strategy appeared to be the most important characteristic influencing the acceptability of energy-saving measures. In general, technical improvements were preferred over behavioral measures and especially shifts in consumption. Further, home energy-saving measures were more acceptable than transport energy-saving measures. The amount of energy savings was the least important characteristic: there was hardly any difference in the acceptability of measures with small and large energy savings. Except for respondents differing in environmental concern, there were no differences in average acceptability of the energy-saving measures between respondent groups. However, some interesting differences in relative preferences for different types of energy-saving measures were found between respondent groups.

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The foliar chemistry of sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since 1989 with ammonium sulfate ((NH4)2SO4) at a rate of 25.2 kg N·ha–1·year–1. Foliar N concentrations were higher in all tree species within the treated watershed compared with trees within the reference watershed. Foliar Ca and Mg concentrations were lower in American beech and red spruce within the treated watershed. There were no significant differences in foliar K concentrations between watersheds. Foliar P and Mn concentration differences between watersheds were inconsistent among years. Differences in foliar N concentrations between watersheds declined over time in sugar maple but not in red spruce or American beech. Differences in foliar Ca and Mg concentrations between the treated and reference watersheds increased over time for American beech and red spruce, primarily because of a consistent decline in concentrations of these nutrients in trees within the treated watershed. No temporal trends in foliar Ca and Mg concentration differences between watersheds were observed for sugar maple.

Responses in basal area increment (BAI) of sugar maple (Acer saccharum Marsh.) and red spruce (Picea rubens Sarg.) to chronic ammonium sulfate ((NH 4 ) 2 SO 4 ) treatment were examined at the Bear Brook Watershed in Maine. The Bear Brook Watershed is a pair-watershed forest ecosystem study with West Bear watershed treated with (NH 4 ) 2 SO 4 at a rate of 1800 equiv.·ha -1 ·year -1 since 1989, while East Bear watershed serves as a reference. Following 10 years of treatment, BAI was significantly higher for sugar maple trees growing in the treated watershed, with yearly increases relative to the reference watershed ranging from 13% in 1999 to 104% in 1996. The increase in sugar maple radial growth was attributed to a fertilization effect from the (NH 4 ) 2 SO 4 treatment. A reduction in BAI in sugar maple growing in the treated watershed observed in 1998 and 1999 was attributed to internal stresses and growth allocation to crown recovery after the severe 1998 ice storm. Red spruce showed no BAI growth responses to the treatment. Lower foliar Mg and Ca concentrations in red spruce in the treated watershed and lower soil responses to N enrichment in treated softwood stands compared with treated hardwood stands could explain the lack of BAI response in red spruce.