ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Sampling in 1977 was restricted to only two sampling dates as our efforts were being
extended to related studies at another experimental forest.
The sampling unit consisted of a cylindrical core of litter, humus, and mineral
soil, which was extracted froni the forest floor by driving a hollow, hinged, metal
cylinder into the ground with a sledge. The cylinder, 5 cm (2 in) in diameter, was
driven deep enough to penetrate to at least 10 cm (4 in) into the mineral soil. The
cylinder and its core were then extracted from the soil and the cylinder laid on its
side. A hinged section of the cylinder was opened exposing the sample core.
The core was marked into four substrates--litter, humus, wood, and mineral soil. The
temperature was taken with a thermistor probe and recorded for each of the substrates.
The depth of each substrate was measured to the nearest centimeter, and beginning at
a point 6 cm (2.25 in) deep (with some cores in the controls, the mineral soil was
sampled to a depth of 18 cm 17 in] in the mineral soil), each substrate was sliced off
In 2 cm (0.75 in) increments. Each sample was labelled as to: date, cutting method
and subtreatment, plot number, core number, core substrate and substrate sequence, and
placed in a 113- or 226-gram (4- or 8-ounce) soil tin for transport to the laboratory,
Once removed to the lab, each substrate core sample was weighed. The sample was
then placed on a cheese cloth-covered hardware cloth screen in a split Tullgren
funnel. The funnels were placed on shelves with an alcohol vial below the funnel and
a 40 watt bulb over the top of the cylinder above the funnel. Once the apparatus was
ready, the lights were turned on, be inning with just a glow, and by using a regu-
lating rheostat, the light (and heat 3 intensity increased gradually each day. After
9 days, the vials, properly label led, were removed. The substrate samples were oven
dried at 60' C for 24 hours, weighed, placed in a muffle furnace for 24 hours at 600' C
and weighed again for combustion analysis. Soil moisture and organic matter data were
recorded.
As time permitted, the arthropods in the vials were separated from the debris
that also precipitated into the vials, and were sorted and classified.
RESULTS
At this time, we are only able to present and discuss the 1976 data, without any
statistical analysis, from our study area at Coram Experimental Forest. Therefore,
these results must be tempered accordingly and interpreted as tentative. The complete
results of this study, as well as a companion study conducted simultaneously and
subsequently at another experimental forest, are not available at this time. When the
analyses are completed for both of these studies, the results will be published in a
subsequent paper.
Arthropods Coll ected
During the 3-year course of this study, we collected forest litter, humus, and
soil mesofauna representing at least 7 classes of arthropods, including 3 orders of
Arachnida and 12 orders of Insecta. By far the most abundant animals were Acari or
mites (~rachnida). The next most abundant group, though far less than the mites, were
three families of Collembola. All other animals, though represented in the collections,