Wednesday, April 29, 2009

Today we went to a native remnant site to collect soil samples and that went well, but then the weather went south quickly. More photos tomorrow. The video below sums up the change while we were sampling soils to determine the seed bank of A. desertorum and annual wheatgrass.
After returning at 2PM we warmed up and set up an experiment that will investigate the effects of simulated bovine urine (SBU) on microbial biomass in soils collected from the 4 species of interest. By using inhibitors of urease (the enzyme that breaks down urea into CO2 and NH3)and bacteria we will be able to quantify the response of soil bacteria to SBU and the effects of invasive species on soil urease levels. Urease is an extracellular enzyme produced by plants, fungi and bacteria that is functional in the soil matrix but is also excreted in response to urea addition to the soil.
Colonies are beginning to grow on the bacterial petri plates that we poured yesterday (Tuesday) and we will count them in the morning. We plan to get out in the field tomorrow to do a companion SBU application in the field (we had planned to do this today but the snow and low temps made it impossible).

1 comment:

  1. The wind and cold wasn't much fun when we were out in the field, but it was a good day for birds. We saw 9 more species on our soil collecting trip.

    Great Blue Heron



    White-throated Swift

    Horned Lark-

    Townsend’s Solitaire

    White-crowned Sparrow

    Brewer’s Blackbird
    Red-winged Blackbird-

    There were big flocks of Horned Larks everywhere, and the two Osprey we saw were courting! They were flying high over head whistling and one was carrying a fish for the other. The way Osprey carry fish is particularly interesting. They often point the fish head first into the wind so it's more aerodynamic (see link above). This would have been crucial with blustery flying conditions yesterday!