\log
The initial iteration of the documentation section of this file was
created by Gina Adams in late December 1997. The documentation and
data sections of this file were provided by Gina Adams via floppy
diskette on 23 December 1997. Minor editorial revisions were made
by Mike Hartman, and the file was placed under sccs control on 17
April 2001.
\doc
TITLE. Effect of krummholz establishment on soil previously occupied by
tundra: bulk density.
ABSTRACT. Previous work has shown that bulk density is lower in the A
horizon of soils directly under tree islands (Englemann spruce (Picea
Englemanii) and subalpine fir (Abies lasiocarpa)) than in adjacent
tundra soil. We compiled a dataset of bulk densities from soils that
had been previously collected at several dates in 1994 and 1996. The
results from this large dataset confirmed those of Pauker and Seastedt
(1996); soils within tree islands had lower bulk densities from those
of other sites.
INVESTIGATOR. Tim Seastedt, INSTAAR, CB 450, University of Colorado,
Boulder, CO, 80309-0450, (303) 492-3302 or (303) 492-0434,
tims@culter.colorado.edu.
VARIABLES. soil depth, soil bulk density.
KEYWORDS. soil bulk density, soil moisture, tree islands, krummholz, tundra,
LOCATION. Study sites were randomly selected subalpine fir and Engelmann
spruce tree islands in dry meadows on Niwot Ridge. The study area
encompassed the north and south facing slopes of a saddle east of
the tundra lab on Niwot Ridge. The elevation of the study site was
approximately 3600 m. Samples and original data are stored in Research
Laboratory #1 (Room 178a) at INSTAAR.
TIMING. Samples were collected in the summers of 1994 and 1996.
CITATIONS. [1]Marr, J.W. 1977 The development and movement of tree
islands near the upper limit of tree growth in the Southern Rocky
Mountains. Ecology 58:1159-1164.
[2]Burns, S. 1980. Alpine soil distribution and development. Indian
Peaks, Colorado Front Range. PhD dissertation, University of Colorado,
Boulder. 360 pp.
[3]Thorn, C.E. 1982. Gopher Disturbance: Its variability by Braun-Blanquet
vegetation units in the Niwot ridge alpine tundra zone, Colorado Front Range,
USA. Arctic and Alpine Research14:45-51.
[4]Holtmeier, F-K and Broll, G. 1992. The influence of tree islands and
microtopography on pedeological conditions in the forest-alpine tundra
ecotone on Niwot Ridge, Colorado Front Range, USA. Arctic and Alpine
Research 24: 216-228.
[5]Pauker, S. J and Seastedt, T.R. 1996. The effect of mobile tree islands
on soil carbon storage in tundra ecosystems. Ecology 77(8): 2563-2576.
[6]Seastedt, T.R. and Adams, G.A. 2001. Effects of mobile tree islands
on alpine tundra soils. Ecology 82:8-15.
COMMENTS. Data were provided via floppy diskette by Gina Adams. Tree
island samples were collected in minimal snow cover soil described by
Burns (1980) as follows: The soil is composed of Pergelic Cryumbrept of
a loamy-skeletal, mixed type, probably eolian in origin with moderately
thick, fine-textured A horizons overlying a cambic B horizon. Where A
horizons are not thick enough to be classified as umbric epipedon, soil
is classified as Dystric Pergelic Cryochrept of a coarse-loamy, mixed
type. These latter characteristics described the soil on the windward
side of tree islands, which was confirmed by Holtmeier et. al. (1992).
Less than 15% rock cover occurs on the ground surface, although
extremely rocky areas found in this soil type are have been interpreted
to be edges of buried patterned ground, suggesting extensive permafrost
in the past. Vegetational communities dominating this dry meadow area
are primarily Association Selaginello-Kobresietum myosuroidis, and
Association Caricetum elynoidis with some areas of Acomastylis rossii
(Burns 1980). Pocket gopher (Thomomys talpoides) disturbance occurs
regularly in the Acomastylis (Thorn 1982), leaving esker-like mounds of
soil on the surface. Various forbs and willows (Salix brachycarpa) tend
to invade the wind-sheltered leeward side of tree islands, and are
eventually either killed by the advancing tree, or become mixed with
the branches of the island (Marr 1977).
The tree islands used for study were a random sample from a larger
group that met the following criteria:. - they were large enough to
have affected the soil for many years (at least 5m long) - they were
not located on the most rocky soils (fell-field) - there was a patch of
undisturbed tundra (dry meadow, dominated by Kobresia mysuroides)
within 5m of the krummholz edge. Soil cores were taken to a depth of
15cm using 3.6 cm diameter PVC pipes. At each tree island, soils were
sampled within the krummholz (at least 50cm inside the krummholz,
towards the windward end of the tree island (i.e. the location that had
been forested for the greatest length of time), in the undisturbed
tundra (less than 5m upslope and downslope from the tree island), 1 m
leeward of the krummholz and 1m windward of the krummholz. We attempted
to remove the litter and fragmented organic matter (O horizon) of the
tree island soils. No O horizon existed on tundra soils. Each
location was sampled on more than one date but statistical analysis
revealed that there was no significant effect of sample date on bulk
density. In order to determine bulk density, each soil core was air
dried and sieved. The mass of the sieved soil was measured. Bulk
density = mass of soil core/volume.
Sample identification codes are comprised of 7 characters. The first
three characters denote the i.d of the tree island (e.g. T01 through
T12). The codes were assigned to each particular tree island in
previous experiments. The next three characters refer to the location
of the soil sample collected. W01 = 1m windward of the tree island,
K01 = inside the krummholz, T01 = tundra site and L01 = < 1m leeward of
the tree island. The final (7th) character provides information about
the tree species. F = subalpine fir, S = Engleman Spruce and X = no
species information available.
The bulk density data in this file, meaned across sampling dates, were
used to calculate carbon and nitrogen properties that can be found at:
http://culter.colorado.edu/exec/.extracttoolA?krmslcnp.ts
Exact sampling dates were not provided. However, samples were taken at
5 dates in 1996 and at 2 dates in 1994. The date label is therefore,
9601 through 9605 and 9401 and 9402.
For samples taken on 9601 through 9603, the mass of bag was not recorded.
However, mass of bag was recorded for samples taken on 9604 and 9605 and
there was very little variation in bag mass. Therefore, the mean from 9604
and 9605 was used for 9601 through 9603. All depths of 1994 soil cores
were 15cm.
\type
statistical
\header
COL1. label=date sample was collected (yyxx), type=string, units=none,
missing value indicator=, minimum=, minimum=9401, maximum=9605,
precision=
COL2. label=sample identification code, type=string, units=none,
missing value indicator=, minimum=, maximum=, precision=
COL3. label=depth of soil core, type=real, units=cm, missing value
indicator=absence of value, minimum=, maximum=, precision=
COL4. label=mass of bag, type=real, units=g, missing value indicator=absence
of value, minimum=, maximum=, precision=
COL5. label=bag and soil core mass, type=real, units=g, missing
value indicator=absence of value, minimum=, maximum=, precision=
COL6. label=soil core mass, type=real, units=g, missing value
indicator=absence of value, minimum=, maximum=, precision=
COL7. label=soil core volume , type=real, units=cm3, missing value
indicator=absence of value, minimum=, maximum=, precision=
COL8 label=soil core bulk density, units=g/cm3, missing value
indicator=absence of value, minimum=, maximum=, precision=
{*********************************************************************
If the data section below contains no data then you will need to
obtain permission from the investigator listed in the documentation
section of this file. If you have obtained permission or if the data
are already contained in this file, include the following
acknowledgment (in addition to an acknowledgment of the investigator)
in any published use of these data: "Logistical support
and/or data were provided by the Niwot Ridge Long-Term Ecological
Research project (NSF DEB 0423662) and the Mountain Research Station
(BIR 9115097)." Please send 4 reprints or high-quality copies of any
such publications to Todd Ackerman, NWT LTER data manager,
INSTAAR, CB 450, University of Colorado, Boulder, CO, 80309-0450.
The data contained in these files have many sources. Generally,
data collected prior to 1993 would have been subjected to quality
control standards imposed by the investigator. Data after 1992
were likely to have been manually entered and/or processed in the
NWT LTER central data management laboratory. Detailed information
on the quality control protocols and programs associated with any
data routed through the NWT LTER data management laboratory will
be supplied upon request. The user of these data should be aware
that, while efforts have been taken to ensure that these data are
of the highest quality, there is no guarantee of perfection for
the data contained herein and the possibility of errors exists.
If you encounter questionable data, please contact the NWT LTER
data manager (todda@culter.colorado.edu; (303) 492-4771) so that
the data can be corrected or qualified. Thus, these data should
be considered dynamic in that past data may be modified and future
data will be appended.
******************************************************************}
\data
9601,T01T01X,15,25.40886,71.404,45.99514,152.7,0.301212
9601,T01K01X,15,25.40886,33.443,8.03414,152.7,0.052614
9601,T01L01X,15,25.40886,72.147,46.73814,152.7,0.306078
9601,T01W01X,15,25.40886,70.323,44.91414,152.7,0.294133
9601,T02T01X,15,25.40886,80.396,54.98714,152.7,0.360099
9601,T02K01X,13,25.40886,71.543,46.13414,132.34,0.348603
9601,T02L01X,15,25.40886,95.802,70.39314,152.7,0.46099
9601,T02W01X,15,25.40886,70.423,45.01414,152.7,0.294788
9601,T03T01X,15,25.40886,78.972,53.56314,152.7,0.350774
9601,T03K01X,14,25.40886,59.844,34.43514,142.52,0.241616
9601,T03L01X,15,25.40886,82.784,57.37514,152.7,0.375738
9601,T03W01X,15,25.40886,103.795,78.38614,152.7,0.513334
9601,T04T01F,15,25.40886,80.907,55.49814,152.7,0.363446
9601,T04K01F,15,25.40886,84.301,58.89214,152.7,0.385672
9601,T04L01F,14,25.40886,90.579,65.17014,142.52,0.45727
9601,T04W01F,15,25.40886,92.106,66.69714,152.7,0.436785
9601,T05T01X,15,25.40886,84.313,58.90414,152.7,0.385751
9601,T05K01X,15,25.40886,56.899,31.49014,152.7,0.206222
9601,T05L01X,15,25.40886,103.853,78.44414,152.7,0.513714
9601,T05W01X,15,25.40886,82.978,57.56914,152.7,0.377008
9601,T06T01F,15,25.40886,88.564,63.15514,152.7,0.41359
9601,T06K01F,13,25.40886,50.181,24.77214,132.34,0.187186
9601,T06L01F,15,25.40886,70.314,44.90514,152.7,0.294074
9601,T06W01F,15,25.40886,81.159,55.75014,152.7,0.365096
9601,T07T01F,15,25.40886,76.965,51.55614,152.7,0.33763
9601,T07K01F,15,25.40886,58.2,32.79114,152.7,0.214742
9601,T07L01F,14,25.40886,57.563,32.15414,142.52,0.225611
9601,T07W01F,15,25.40886,46.353,20.94414,152.7,0.137159
9601,T08T01S,15,25.40886,84.126,58.71714,152.7,0.384526
9601,T08K01S,15,25.40886,65.035,39.62614,152.7,0.259503
9601,T08L01S,13,25.40886,94.865,69.45614,132.34,0.524831
9601,T08W01S,13,25.40886,92.514,67.10514,132.34,0.507066
9601,T09T01F,14,25.40886,104.498,79.08914,142.52,0.554934
9601,T09K01F,15,25.40886,91.35,65.94114,152.7,0.431835
9601,T09L01F,15,25.40886,96.502,71.09314,152.7,0.465574
9601,T09W01F,13,25.40886,66.053,40.64414,132.34,0.307119
9601,T10T01F,15,25.40886,73.005,47.59614,152.7,0.311697
9601,T10K01F,15,25.40886,96.579,71.17014,152.7,0.466078
9601,T01L01F,14,25.40886,76.489,51.08014,142.52,0.358407
9601,T10W01F,15,25.40886,90.212,64.80314,152.7,0.424382
9601,T11T01S,15,25.40886,84.097,58.68814,152.7,0.384336
9601,T11K01S,12,25.40886,61.487,36.07814,122.16,0.295335
9601,T11T01S,15,25.40886,75.121,49.71214,152.7,0.325554
9601,T11T01S,13,25.40886,63.313,37.90414,132.34,0.286415
9601,T12T01X,15,25.40886,85.584,60.17514,152.7,0.394074
9601,T12K01X,15,25.40886,51.316,25.90714,152.7,0.16966
9601,T12L01X,15,25.40886,84.802,59.39314,152.7,0.388953
9601,T12W01X,15,25.40886,99.29,73.88114,152.7,0.483832
9602,T01K01X,15,25.40886,44.326,18.91714,152.7,0.123884
9602,T01L01X,15,25.40886,74.39,48.98114,152.7,0.320767
9602,T01W01X,15,25.40886,52.252,26.84314,152.7,0.17579
9602,T02K01X,15,25.40886,61.976,36.56714,152.7,0.23947
9602,T02L01X,15,25.40886,75.669,50.26014,152.7,0.329143
9602,T02W01X,15,25.40886,61.477,36.06814,152.7,0.236203
9602,T03K01X,15,25.40886,53.463,28.05414,152.7,0.183721
9602,T03L01X,15,25.40886,87.184,61.77514,152.7,0.404552
9602,T04K01F,14,25.40886,39.182,13.77314,142.52,0.09664
9602,T04L01F,15,25.40886,49.836,24.42714,152.7,0.159968
9602,T04W01F,15,25.40886,77.241,51.83214,152.7,0.339438
9602,T05K01X,15,25.40886,99.871,74.46214,152.7,0.487637
9602,T05L01X,15,25.40886,76.231,50.82214,152.7,0.332823
9602,T05W01X,15,25.40886,68.068,42.65914,152.7,0.279366
9602,T06K01F,12,25.40886,31.236,5.82714,122.16,0.047701
9602,T06L01F,15,25.40886,106.053,80.64414,152.7,0.528121
9602,T06W01F,15,25.40886,99.312,73.90314,152.7,0.483976
9602,T07K01F,15,25.40886,50.219,24.81014,152.7,0.162476
9602,T07L01F,15,25.40886,108.505,83.09614,152.7,0.544179
9602,T07W01F,15,25.40886,94.777,69.36814,152.7,0.454277
9602,T08K01S,15,25.40886,67.296,41.88714,152.7,0.27431
9602,T08L01S,15,25.40886,77.375,51.96614,152.7,0.340315
9602,T08W01S,14,25.40886,41.592,16.18314,142.52,0.11355
9602,T09K01F,14,25.40886,101.875,76.46614,142.52,0.536529
9602,T09L01F,12,25.40886,51.693,26.28414,122.16,0.215162
9602,T09W01F,15,25.40886,74.481,49.07214,152.7,0.321363
9602,T10K01F,14,25.40886,47.247,21.83814,142.52,0.153229
9602,T10W01F,15,25.40886,70.035,44.62614,152.7,0.292247
9602,T11K01S,12,25.40886,75.412,50.00314,122.16,0.409325
9602,T12K01X,15,25.40886,83.266,57.85714,152.7,0.378894
9602,T12L01X,15,25.40886,92.8,67.39114,152.7,0.44133
9602,T12W01X,15,25.40886,91.769,66.36014,152.7,0.434579
9603,T10K01F,15,25.40886,71.13,45.72114,152.7,0.299418
9603,T11K01S,12,25.40886,36.654,11.24514,122.16,0.092053
9604,T04T01F,15,25.403,103.128,77.725,152.7,0.509005
9604,T04W01F,15,25.412,119.536,94.124,152.7,0.616398
9604,T05T01X,15,25.412,97.292,71.88,152.7,0.470727
9604,T06T01F,15,25.386,83.816,58.43,152.7,0.382646
9604,T06W01F,15,25.403,95.308,69.905,152.7,0.457793
9604,T10T01F,15,25.391,107.404,82.013,152.7,0.537086
9604,T10W01F,15,25.394,112.875,87.481,152.7,0.572895
9604,T11T01S,15,25.376,118.961,93.585,152.7,0.612868
9604,T11W01S,14,25.395,89.22,63.825,142.52,0.447832
9604,T12T01X,15,25.449,103.279,77.83,152.7,0.509692
9605,T04W01F,15,25.415,111.81,86.395,152.7,0.565783
9605,T06W01F,15,25.391,110.047,84.656,152.7,0.554394
9605,T10W01F,15,25.379,70.118,44.739,152.7,0.292986
9605,T12T01X,15,25.465,87.561,62.096,152.7,0.406654
9401,T01T01X,15,,,,,0.49658
9401,T01K01X,15,,,,,0.22534
9401,T01L01X,15,,,,,0.53632
9401,T01W01X,15,,,,,0.501
9401,T02T01X,15,,,,,0.62745
9401,T02K01X,15,,,,,0.43953
9401,T02L01X,15,,,,,0.54927
9401,T02W01X,15,,,,,0.62745
9401,T03T01X,15,,,,,0.54143
9401,T03K01X,15,,,,,0.37585
9401,T03L01X,15,,,,,0.62367
9401,T03W01X,15,,,,,0.75385
9401,T04T01F,15,,,,,0.59719
9401,T04K01F,15,,,,,0.28927
9401,T04T01F,15,,,,,0.69813
9401,T04W01F,15,,,,,0.66535
9401,T05T01X,15,,,,,0.63336
9401,T05K01X,15,,,,,0.71369
9401,T05L01X,15,,,,,0.74982
9401,T05W01X,15,,,,,0.48734
9401,T06T01F,15,,,,,0.55887
9401,T06K01F,15,,,,,0.27334
9401,T06L01F,15,,,,,0.49732
9401,T06W01F,15,,,,,0.58081
9401,T07T01F,15,,,,,0.64532
9401,T07K01F,15,,,,,0.41214
9401,T07L01F,15,,,,,0.78204
9401,T07W01F,15,,,,,0.68633
9401,T08T01S,15,,,,,0.56862
9401,T08K01S,15,,,,,0.46198
9401,T08L01S,15,,,,,0.78674
9401,T08W01S,15,,,,,0.77324
9401,T09T01F,15,,,,,0.72879
9401,T09K01F,15,,,,,0.65457
9401,T09L01F,15,,,,,0.68969
9401,T09W01F,15,,,,,0.53168
9401,T10T01F,15,,,,,0.54058
9401,T10K01F,15,,,,,0.69985
9401,T01L01F,15,,,,,0.58545
9401,T10W01F,15,,,,,0.49956
9401,T11T01S,15,,,,,0.57324
9401,T11K01S,15,,,,,0.31489
9401,T11L01S,15,,,,,0.54008
9401,T11W01S,15,,,,,0.57324
9401,T12T01X,15,,,,,0.63228
9401,T12K01X,15,,,,,0.59522
9401,T12L01X,15,,,,,0.61081
9401,T12W01X,15,,,,,0.7201
9402,T01K01X,15,,,,,0.31032
9402,T01L01X,15,,,,,0.51478
9402,T01W01X,15,,,,,0.36686
9402,T02K01X,15,,,,,0.58311
9402,T02L01X,15,,,,,0.68939
9402,T02W01X,15,,,,,0.43461
9402,T03K01X,15,,,,,0.45249
9402,T03L01X,15,,,,,0.58534
9402,T04K01F,15,,,,,0.59876
9402,T04L01F,15,,,,,0.35267
9402,T04W01F,15,,,,,0.54959
9402,T05K01X,15,,,,,0.40315
9402,T05L01X,15,,,,,0.54469
9402,T05W01X,15,,,,,0.59947
9402,T06K01F,15,,,,,0.40691
9402,T06L01F,15,,,,,0.76664
9402,T06W01F,15,,,,,0.71559
9402,T07K01F,15,,,,,0.35133
9402,T07L01F,15,,,,,0.43039
9402,T07W01F,15,,,,,0.32231
9402,T08K01S,15,,,,,0.47876
9402,T08L01S,15,,,,,0.55626
9402,T08W01S,15,,,,,0.30679
9402,T09K01F,15,,,,,0.79108
9402,T09L01F,15,,,,,0.45375
9402,T09W01F,15,,,,,0.5515
9402,T10K01F,15,,,,,0.35562
9402,T10L01F,15,,,,,0.50561
9402,T10W01F,15,,,,,0.65556
9402,T11K01S,15,,,,,0.54828
9402,T11L01S,15,,,,,0.67799
9402,T12K01X,15,,,,,0.35822
9402,T12L01X,15,,,,,0.66557
9402,T12W01X,15,,,,,0.65864