General Information
|
| Title: | Long-Term Sevilleta LTER Core Site Grasshopper Dynamics |
| Identifier: | sev.106.2 |
| Abstract: |
Grasshoppers are important animals in semi-arid environments, both as herbivores and as food resources for higher level consumer animals. Grasshoppers tend to be numerous and represented by many species in semi-arid environments, especially in desert grasslands. Grasshopper species range from environmental specialists, to environmental generalists. Grasshopper populations tend to change considerably from year to year, often in response to annual variation in rainfall and plant production. The purpose of this study was to monitor grasshopper species composition and abundance over a period of many years from black grama grassland, blue grama grassland, creosotebush shrubland, and pinyon/juniper woodland environments at the Sevilleta, in relation to seasonal and annual variation in precipitation and plant production. Data were collected for all individual species to provide information on community dynamics as well as population dynamics. The working research hypothesis for this study was that grasshopper populations in all environments will correlate positively to seasonal and annual variation in precipitation and plant production. Spring grasshopper populations will be especially high during El Nino years, and late summer populations especially high during La Nina years. This study was initiated in 1992, and is ongoing to the present time.
|
| Keywords: |
- consumers
- grasshoppers
- desert grassland
- shrubland
- pinyon/juniper woodland
- Sevilleta
|
|
|
|
Involved Parties
Data Set Creators
|
|
Individual: | Dr. David Lightfoot |
|
Email Address:
|
|
|
Data Set Contacts
|
|
Individual: | Dr. David Lightfoot |
|
Email Address:
|
|
|
|
Organization: | Sevilleta LTER |
|
Position: | Information Manager |
|
Address: |
| Department of Biology, |
| 1 University of New Mexico, |
| Albuquerque, NM 87131 USA |
|
|
Email Address:
|
|
|
|
Data Set Characteristics
| Geographic Region: |
| Geographic Description: | Sevilleta Field Station |
|
Bounding Coordinates:
|
| West: | -106.884 degrees
|
| East: | -106.777116 degrees
|
| North: | 34.35 degrees
|
| South: | 34.35 degrees
|
|
|
|
|
Sampling, Processing and Quality Control Methods
|
Step by Step Procedures
|
| Step 1: |
|
|
Description:
|
Data collection
visual counts of all grasshoppers on each strip transect. The observer slowly walks each transect, flushing grasshoppers ahead with a one-meter long «-inch white PVC pipe. The observer records data on to a voice-activated micro-cassette recorder. Information recorded includes for each individual grasshopper; species, geneder, age class, and the substrate from which the grasshopper was flushed.
|
|
Instrument(s):
| various pocket micro-cassette recorders; Olympus, Sony, Panasonic. |
|
Sampling Area And Frequency:
|
* Study Area Description: Five Points Grass.
* Site Location Description: approximately 2km NW of Five Points, McKenzie Flats.
* Descriptors
- Soil: sandy loam.
- Slope/Aspect: gentle rolling terrain.
- Vegetation Community: black grama grassland.
- Terrain/Physiography: gentle rolling terrain.
- Geology/Lithology: alluvial outwash, limestone and caliche.
- Hydrology - surface/groundwater: slight drainage to the west.
- Size: approximately 2 by 2 km.
- History (if known): intensivey grazed by cattle until 1973.
- Elevation: approximately 1,600 meters.
- Climate (general): semi-arid, summer rain.
* Study Area Description: Five Points Creosotebush.
* Site Location Description: approximately 2km west of Five Points, McKenzie Flats.
* Descriptors
- Soil: sandy loam.
- Slope/Aspect: slight north-facing slope.
- Vegetation Community: Chihuahuan Desert creosotebush/black grama grass.
- Terrain/Physiography: top of Palo Duro Canyon escarpment to south, gentle slope to north.
- Geology/Lithology: alluvial outwash, extensive caliche near surface.
- Hydrology - surface/groundwater: slight drainage to the north.
- Size: approximately 1 by 2 km.
- History (if known): intensively grazed by cattle until 1973.
- Elevation: approximately 1,600 meters.
- Climate (general): semi-arid, summer rain.
* Study Area Description: Blue Grama.
* Site Location Description: approximately 2km south of Burris Well, McKenzie Flats.
* Descriptors
- Soil: gravelly loam.
- Slope/Aspect: slight west-facing slope.
- Vegetation Community: blue grama grassland/some black grama grassland.
- Terrain/Physiography: lower piedmont slope of the Sierra Los Pinos.
- Geology/Lithology: alluvial material, rhyolite and limestone parent material.
- Hydrology - surface/groundwater: pronounced surface drainage to the west.
- Size: approximately 1 by 1 km.
- History (if known): intensively grazed by cattle until 1973.
- Elevation: approximately 1,700 meters.
- Climate (general): semi-arid, summer rain.
* Study Area Description: Goat Draw (Cerro Montosa)
* Site Location Description: Cerro Montosa draw, at north base of Cerro Montosa, Sierra Los Pinos.
* Descriptors
- Soil: rocky loam.
- Slope/Aspect: variable steep slopes, all aspects.
- Vegetation Community: pinyon/juniper woodland, blue grama understory.
- Terrain/Physiography: rough, dissected erosional montane hills, slopes, and drainages.
- Geology/Lithology: variable, rhyolite.
- Hydrology - surface/groundwater: extensive steep arroyo drainages.
- Size: approximately 1 by 3 km.
- History (if known): grazed by cattle until 1973.
- Elevation: approximately 2,000 meters.
- Climate (general): semi-arid montane, summer rain.
|
|
Sampling Description:
|
* Sampling Design
-Physical Dimensions of Sampling Area: 50-meter by one-meter strip transects, between 6, alternating end-points of rodent trap lines on each of 5 rodent trapping webs at each of the 4 sites.
-Plot size: each trapping web is 200-meters diameter, each grasshopper count strip is 50-meters long, by one-meter wide.
-Transect Length: 50-meters.
* Sample Unit: 50 by 1-meter strip transect; 6 strip transects per web, 5 webs per site.
* Frequency of Sampling: twice each year, early summer and late summer.
* Sample Size: 50-meter by one-meter strip transects.
|
|
Data Set Usage Rights
|
Any Sevilleta LTER data set and accompanying metadata can be used for academic, research, and other professional purposes. Permission to use the data is granted to the Data User subject to the following terms: Data User will: 1) notify the designated contact (e.g., Principle Investigator or Data Set Contact) when any derivative work based on or derived from the data and documentation is distributed. 2) notify users that such derivative work is a modified version and not the original data and documentation distributed by the Sevilleta LTER 3) not redistribute original data and documentation 4) acknowledge the support of the Sevilleta LTER and appropriate NSF Grant numbers in any publications using these data and documentation. (e.g. Data sets were provided by the Sevilleta LTER Data Bank. Funding for these data was provided by the National Science Foundation Long-Term Ecological Research program (NSF Grant numbers BSR- 9411976 and DEB-0080529). 5) send two reprints of any publications resulting from use of the data and documentation to the following address: Sevilleta LTER Program Attn: Information Manager Department of Biology University of New Mexico Albuquerque, NM 87131
|
| Access Control: |
| Auth System: | knb |
| Order: | denyFirst |
|
|
