{EML Metadata} {Description of the Data file structure is available at the Niwot Ridge LTER Data page}

\log

The initial iteration of this file was generated by Heather
O'Lear in early January 1994. Minor editorial revisions were
made to the documentation and header sections of the file
by RCI on 5 January 1994 and the file was put under sccs 
control on that date as well.[RCI 5 January 1994] Editorial
revisions to the first iteration were provided by Tim 
Seastedt on 6 January 1994 and incorporated on that date.
[RCI 6 January 1994]

\doc

TITLE. Soil microarthropod densities on Niwot Ridge. 

ABSTRACT. Microarthropod densities in the upper 5 cm of soil 
were estimated for different alpine communities on Niwot Ridge 
in the Front Range of Colorado.  Densitites were higher than 
previously reported and averaged 111,200 individuals/m2. Acari 
dominated this group and composed 80-90% of the fauna; 
Collembola composed an average of 15%. Oribatid mites composed 
23-58% of total densities, while Prostigmatid mites composed 
32-54%. The relative abundance of the Oribatid and 
Prostigmatid mites varied significantly across the landscape, 
with Prostigmatids more abundant in the xeric sites. 
Composition of the detritus-based food web appear to change 
substantially across the snow depth gradient found in the 
alpine tundra.  

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. abundance, composition, fauna list, moisture 
gradient.

KEYWORDS. microarthropods, landscape, alpine, animal species composition.

LOCATION. Study sites in 1992 included the krummholz and 
trough areas directly south of the crest of Niwot Ridge; 
sites in 1993 were on or adjacent to the Saddle snowfence
experiment area. Samples and original data are stored in 
Research Laboratory #1 (Room 178a).

TIMING. begin 10 July 1992, end 26 August 1993, once at each site.

CITATIONS. [1]O'Lear, H.A., and T.R. Seastedt. 1994. Landscape 
patterns of litter decomposition in alpine tundra. Oecologia 99: 95-101.
[2]Seastedt, T.R., and D.A. Crossley, Jr. 1978. Further 
investigations of microarthropod populations using the 
Merchant-Crossley high-gradient extractor. Journal of the 
Georgia Entomological Society 13: 338-344.

COMMENTS. Soil cores (5 cm in depth) were randomly removed 
from selected habitats located on Niwot Ridge. Habitats included 
dry meadow (dry) dominated by Kobresia myosuroides, wet meadow
(wet) dominated by Carex spp. and Sibbaldia spp., mesic meadow
(mes) dominated by Acomastylis rossii, shrub community (shb)
dominated by Salix spp., sub-alpine meadow (sam), krummholz
community (krm), and Acomastylis community adjacent to krummholz 
(abk). The high-gradient extraction method described by Seastedt
and Crossley (1978) was used to remove invertebrates. Extracted 
samples were placed in a gridded petri dish containing gylcerol 
and counts were done using a dissecting scope. Numbers of 
individuals were then multiplied by 552.6 to obtain 
densities/m2. 

\type

statistical.

\header

COL1. label=sample date (yymmdd), type=string, units=none,
missing value indicator=, minimum=920710, maximum=930826, 
precision=

COL2. label=site, type=string, units=none, missing value
indicator=, minimum=, maximum=, precision=

COL3. label=number of immature Oribatid mites, type=integer,
units=none, missing value indicator=, minimum=0, 
maximum=166, precision=

COL4. label=number of adult Oribatid mites, type=integer,
units=none, missing value indicator=, minimum=0, 
maximum=157, precision=

COL5. label=number of Prostigmatid mites, type=integer,
units=none, missing value indicator=, minimum=2, 
maximum=263, precision=

COL6. label=number of Mesostigmatid mites, type=integer,
units=none, missing value indicator=, minimum=0, 
maximum=40, precision=

COL7. label=number of Collembola, type=integer, 
units=none, missing value indicator=, minimum=0, 
maximum=165, precision=

COL8. label=number of other insects, type=integer, 
units=none, missing value indicator=, minimum=0, 
maximum=13, precision=

COL9. label=comments, type=string, units=none, missing value
indicator=, 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

920710 wet  50  33  08  05  28  02
920710 wet  67  29  37  01  09  06
920710 wet 103 129 112  00  08  03
920710 wet  26  39  05  03  05  01
920710 wet  28  65  70  03 121  03
920710 mes  00  28  56  00  26  00
920710 dry  07  05  47  04  34  00
920710 dry  24  09  73  03  06  00
920710 dry  36  38  47  20  44  01
920710 dry  24  34  20  11  11  00
920710 dry  40  45  49  33  60  01
920710 dry  23  03  46  25  18  00
920716 krm  81  23 179  15  17  00
920716 krm  40  13  71  09  14  01
920716 krm  82  89 245  22  20  00
920716 krm  47  22  52  20  08  00
920716 krm 107  62 176  40  49  01
920716 krm 134  82 126  18  23  00
920716 sam  24  22  95  02  07  00   {subalpine meadow}
920716 sam  11  17  37  06  44  04
920716 sam  23  11  60  05  11  00
920716 mes  26  75  47  30  29  02
920716 mes  55  94  39  04  10  00
920716 mes  53  63  65  13  02  01
920716 mes  52  62  85  31  31  01
920710 mes  99  29  47  13  00  00
920710 mes  18  00  02  08  00  01   {"other" is Homoptera}
920716 abk  18  12  58  07  05  03   {Acomastylis by krummholz}
920716 abk  36  08  63  03  14  00   {Acomastylis by krummholz}
930615 shb  49  54  28  01  07  00   {shrub}
930615 shb  55  84  06  09  07  00
930615 dry  06  08  13  02  79  00
930615 dry  15  24  66  08  05  09   {7 of the "other" are Homoptera}
930615 mes  17  06  35  00  03  02   {1 of the "other" is Homoptera}
930615 mes  30  10  35  02  03  05   {4 of the "other" are Homoptera}
930615 wet  36  31  47  01  29  05   {all of the "other" are Homoptera}
930615 wet  58  39  76  01  34  05   {1 of the "other" is Homoptera}
930615 mes  20  23 156  00 125  00
930615 dry  13  08  46  00  08  01   {"other" is Homoptera}
930615 wet  18  08  65  02  16  01   {"other" is Homoptera}
930615 wet  13  19  15  05  34  03   {2 of the "other" are Homoptera}
930615 dry  12  18  60  02  02  00
930615 shb  48  40  57  00  20  02   {all of the "other" are Homoptera}
930622 dry  10  51 299  02  12  04   {3 of the "other" are Homoptera}
930622 mes  84  52  96  03  04  01   {"other" is Homoptera}
930622 mes  24  05  43  01  09  03
930622 dry  66  71 312  08  21  06   {2 of the "other" are Homoptera}
930622 wet  15  28 139  00  10  03
930622 shb  69  38 113  02  23  00
930622 shb  45  46  45  02  14  00
930622 wet  22  24  74  01  11  02
930622 dry  37  43 198  01  22  03   {2 of the "other" are Homoptera}
930622 shb 135 157 167  00  17  00
930622 shb 161  94 124  01  14  02   {all of the "other" are Homoptera}
930622 mes  09  14  48  00  11  07   {4 of the "other" are Homoptera}
930622 wet 135 145 241  00  24  05   {4 of the "other" are Homoptera}
930622 wet  39  64  74  00  07  00
930622 mes  11  13 157  00 165  00
930826 dry  60  44 160  00  09  05
930826 wet 166  75  15  00  05  03
930826 wet  24  36  43  00  17  09
930826 dry  24  22 263  00 141  08
930826 mes  35  10  68  01  03  02
930826 shb  72  18  80  01  20  00
930826 shb  95  80  68  05  14  00
930826 mes 113  63  90  03  05  04
930826 mes  22  24  62  02  31  02
930826 mes  49  24  70  00  01  06
930826 shb  75  23  54  03  16  03
930826 shb 132  64 240  04  22  01
930826 wet  14  19  94  04  15  13
930826 wet  56  44  49  01  34  09
930826 dry  35  51 154  00  05  04
930826 dry  00  00  18  00  61  00