A comparison of the male and female roles in raising a nestling in the Rose-breasted Grosbeak (Pheuticus leudovicianus).

http://deepblue.lib.umich.edu/bitstream/2027.42/53758/1/2193.pdfDescription of 2193.pdf : Access restricted to on-site users at the U-M Biological Station

Dryopteris fragrans: a few fun fragrant fern facts.

http://deepblue.lib.umich.edu/bitstream/2027.42/53757/1/2192.pdfDescription of 2192.pdf : Access restricted to on-site users at the U-M Biological Station

Annual basal area increment and growth duration of Pinus taeda in response to eight years of free-air carbon dioxide enrichment

Rising CO is predicted to increase forest productivity, although the duration of the response and how it might be altered by variation in rainfall, temperature and other environmental variables are not well understood. We measured the basal area of rapidly growing Pinus taeda trees exposed to free-air CO enrichment for 8 years and used these measurements to estimate monthly and annual growth. We used these measurements in a statistical model to estimate the start and end of growth in each year. Elevated CO increased the basal area increment (BAI) of trees by 13-27%. In most years, exposure to elevated CO increased the growth rate but not the duration of the active growth period. With the exception of 1 year following an extreme drought and a severe ice storm, BAI was positively correlated with the amount of rainfall during the active growth period. The interannual variation in the relative enhancement of BAI caused by elevated CO was strongly related to temperature and rainfall, and was greatest in years with high vapor pressure deficit. There was no evidence of a systematic reduction in the stimulation of growth during the first 8 years of this experiment, suggesting that the hypothesized limitation of the CO response caused by nitrogen availability has yet to occur. © 2006 Blackwell Publishing Ltd. 2 2 2 2 2

Increases in the flux of carbon belowground stimulate nitrogen uptake and sustain the long-term enhancement of forest productivity under elevated CO2

The earth’s future climate state is highly dependent upon changes in terrestrial C storage in response to rising concentrations of atmospheric CO2. Here we show that consistently enhanced rates of net primary production (NPP) are sustained by a C-cascade through the root-microbe-soil system; increases in the flux of C belowground under elevated CO2 stimulated microbial activity, accelerated the rate of soil organic matter decomposition and stimulated tree uptake of N bound to this SOM. This process set into motion a positive feedback maintaining greater C gain under elevated CO2 as a result of increases in canopy N content and higher photosynthetic N-use efficiency. The ecosystem-level consequence of the enhanced requirement for N and the exchange of plant C for N belowground is the dominance of C storage in tree biomass but the preclusion of a large C sink in the soil

Increases in the flux of carbon belowground stimulate nitrogen uptake and sustain the long-term enhancement of forest productivity under elevated CO₂.

The earth's future climate state is highly dependent upon changes in terrestrial C storage in response to rising concentrations of atmospheric CO₂. Here we show that consistently enhanced rates of net primary production (NPP) are sustained by a C-cascade through the root-microbe-soil system; increases in the flux of C belowground under elevated CO₂ stimulated microbial activity, accelerated the rate of soil organic matter decomposition and stimulated tree uptake of N bound to this SOM. This process set into motion a positive feedback maintaining greater C gain under elevated CO₂ as a result of increases in canopy N content and higher photosynthetic N-use efficiency. The ecosystem-level consequence of the enhanced requirement for N and the exchange of plant C for N belowground is the dominance of C storage in tree biomass but the preclusion of a large C sink in the soil