Summary Information
Biome Transition Along Elevational Gradients in New Mexico (SEON) Study: Flux Tower Net Primary Productivity (NPP) Quadrat Study at the Sevilleta National Wildlife Refuge, New Mexico (2011- present)
Creator:
Individual: Marcy Litvak
Organization: SEV LTER
Physical Address:
Delivery Address: ,
Postal Code: 0
Email: mlitvak@unm.edu
System ID: 14590
Associated Party:
Individual: Megan McClung
Organization: SEV LTER
Physical Address:
Delivery Address: 1 University of New Mexico, 167 Castetter Hall, MSC03 2020
City: Albuquerque
Locality: NM
Postal Code: 87131
Phone: United States
Email: mmcclung@sevilleta.unm.edu
Role: data manager
Associated Party:
Individual: Stephanie Baker
Organization: SEV LTER
Phone: (505) 277-8119
Email: srbaker@sevilleta.unm.edu
Role: field crew
Associated Party:
Individual: Megan McClung
Organization: SEV LTER
Physical Address:
Delivery Address: 1 University of New Mexico, 167 Castetter Hall, MSC03 2020
City: Albuquerque
Locality: NM
Postal Code: 87131
Phone: United States
Email: mmcclung@sevilleta.unm.edu
Role: field crew
Associated Party:
Individual: Chandra Tucker
Organization: SEV LTER
Email: ctucker@sevilleta.unm.edu
Role: field crew
Publication Date: 2015
Language: english
Abstract:
The varied topography and large elevation gradients that characterize the arid and semi-arid Southwest create a wide range of climatic conditions - and associated biomes - within relatively short distances. This creates an ideal experimental system in which to study the effects of climate on ecosystems. Such studies are critical givien that the Southwestern U.S. has already experienced changes in climate that have altered precipitation patterns (Mote et al. 2005), and stands to experience dramatic climate change in the coming decades (Seager et al. 2007; Ting et al. 2007). Climate models currently predict an imminent transition to a warmer, more arid climate in the Southwest (Seager et al. 2007; Ting et al. 2007). Thus, high elevation ecosystems, which currently experience relatively cool and mesic climates, will likely resemble their lower elevation counterparts, which experience a hotter and drier climate. In order to predict regional changes in carbon storage, hydrologic partitioning and water resources in response to these potential shifts, it is critical to understand how both temperature and soil moisture affect processes such as evaportranspiration (ET), total carbon uptake through gross primary production (GPP), ecosystem respiration (Reco), and net ecosystem exchange of carbon, water and energy across elevational gradients.We are using a sequence of six widespread biomes along an elevational gradient in New Mexico -- ranging from hot, arid ecosystems at low elevations to cool, mesic ecosystems at high elevation to test specific hypotheses related to how climatic controls over ecosystem processes change across this gradient. We have an eddy covariance tower and associated meteorological instruments in each biome which we are using to directly measure the exchange of carbon, water and energy between the ecosystem and the atmosphere. This gradient offers us a unique opportunity to test the interactive effects of temperature and soil moisture on ecosystem processes, as temperature decreases and soil moisture increases markedly along the gradient and varies through time within sites.This dataset examines how different stages of burn affects above-ground biomass production (ANPP) in a mixed desert-grassland. Net primary production is a fundamental ecological variable that quantifies rates of carbon consumption and fixation. Estimates of NPP are important in understanding energy flow at a community level as well as spatial and temporal responses to a range of ecological processes.Above-ground net primary production is the change in plant biomass, represented by stems, flowers, fruit and foliage, over time and incorporates growth as well as loss to death and decomposition. To measure this change the vegetation variables in this dataset, including species composition and the cover and height of individuals, are sampled twice yearly (spring and fall) at permanent 1m x 1m plots. The data from these plots is used to build regressions correlating biomass and volume via weights of select harvested species obtained in SEV157, "Net Primary Productivity (NPP) Weight Data." This biomass data is included in SEV292, "Flux Tower Seasonal Biomass and Seasonal and Annual NPP Data."
Keywords:
Keyword: primary production
Keyword Thesaurus: Core Areas
Keywords:
Keyword: measurements
Keyword: climate
Keyword: elevation
Keyword: production
Keyword: primary production
Keyword: plants
Keyword: foliage
Keyword: grasses
Keyword: forbs
Keyword: vegetation
Keyword: stems
Keyword Thesaurus: LTER Controlled Vocabulary
Additional Information:
Other researchers involved with collecting samples/data: Chandra Tucker (CAT; 04/2014-present), Megan McClung (MAM; 04/2013-present), Stephanie Baker (SRB; 09/2010-present), John Mulhouse (JMM; 08/2009-06/2013), Amaris Swann (ALS; 08/2008-present)Data updated 08/18/15: MOSQ changed to MUSQ3; ARPUP6 changed to ARPU9; SPWR changed to SPPO6; DANA changed to DANAN.
Intellectual Rights:
Data Policies
This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement of the Sevilleta LTER. Datasets must be cited as in the example below. Muldavin, E. 2004. Sevilleta LTER Fertilizer NPP Study Dataset. Albuquerque, NM: Sevilleta Long Term Ecological Research Site Database: SEV155. (Date of download) A copy of any publications using these data must be supplied to the Sevilleta LTER Information Manager.
Distribution:
Online:
URL: http://sev.lternet.edu/node/6336
Coverage:
Geographic Goverage:
Geographic Description: Location: Deep Well is located on McKenzie Flats and is site of the longest running SEV LTER met station, number 40, which has been active since 1988.  In addition to studies of meteorological variables, core line-intercept vegetation transects and line-intercept transects from the 1995 and 2001 Deep Well fires are sampled here.  The mini-rhizotron study, blue and black grama compositional comparison, blue and black grama patch dynamics investigation, and kangaroo rat population assessement are all ongoing here.  Deep Well Blue/Black Grama Mixed is also the location of the warming and monsoon experiments, as well as portions of the line-intercept and vegetation removal studies. On August 4, 2009, a lightning-initiated fire began on the Sevilleta National Wildlife Refuge. By August 5, 2009, the fire had reached the area of Deep Well Blue/Black Grama Mixed.  While portions of this site were burned, the entirety was not.  See individual projects for further information on the effects of the fire.Vegetation: The vegetation of Deep Well Blue/Black Grama Mixed is Chihuahuan Desert Grassland, dominated by black grama (Bouteloua eriopoda) and blue grama (B. gracilis). Other grasses found at the site include dropseeds (Sporobolus spp.) and threeawns (Aristida spp.). Shrubs are uncommon but those that occur include Yucca glauca, Ephedra torreyi, and four-wing saltbush (Atriplex canescens). Herbaceous plants include Plantago purshii, Hymenopappus filifolius, and globe mallows (Sphaeralcea spp.). ,
Bounding Coordinates:
West Bounding Coordinates: -106.7358
East Bounding Coordinates: -106.7358
North Bounding Coordinates: 34.3592
South Bounding Coordinates: 34.3592
Bounding Altitude:
Altitude Minimum: 1600
Altitude Maximum: 1600
Altitude Units: meter
Temporal Coverage:
Date Range:
Begin Date:
Calendar Date: 2012-01-06
End Date:
Calendar Date: 2015-04-22
Contact:
Position Title: Information Manager
Organization: LTER Network Office
Physical Address:
Delivery Address: UNM Biology Department, MSC03-2020
Delivery Address: 1 University of New Mexico
City: Albuquerque
Locality: NM
Postal Code: 87131-0001
Phone: USA
Phone: 505 277-2535
Phone: 505 277-2541
Email: tech-support@lternet.edu
URL: http://www.lternet.edu
Contact:
Individual: Sevilleta Information Manager
Organization: SEV LTER
Email: data-use@sevilleta.unm.edu
Contact:
Individual: Marcy Litvak
Organization: SEV LTER
Physical Address:
Delivery Address: ,
Postal Code: 0
Email: mlitvak@unm.edu
System ID: 14590
Publication Place: Sevilleta LTER
Method Step:
Description:
Above-Ground Net Primary Productivity (ANPP) measurements:Above-ground net primary production data is collected two times each year, spring, and fall. Spring measurements are taken in April or May when shrubs and spring annuals have reached peak biomass. Fall measurements are taken in either September or October when summer annuals have reached peak biomass but prior to killing frosts. Vegetation data is collected on a palm top computer. A 1-m2 PVC-frame is placed over the fiberglass stakes that mark the diagonal corners of each quadrat. When measuring cover it is important to stay centered over the vegetation in the quadrat to prevent errors caused by angle of view (parallax). Each PVC-frame is divided into 100 squares with nylon string. The dimensions of each square are 10cm x 10cm and represent 1 percent of the total area.The cover (area) and height of each individual live (green) vegetative unit that falls within the one square meter quadrat is measured. A vegetative unit consists of an individual size class (as defined by a unique cover and height) of a particular species within a quadrat. Cover is quantified by counting the number of 10cm x 10cm squares filled by each vegetative unit. It is possible to obtain a total percent cover greater than 100% for a given quadrat because vegetative units for different species often overlap.Niners and plexidecs are additional tools that can help accurately determine the cover a vegetative unit. A niner is a small, hand-held PVC frame that can be used to measure canopies. Like the larger PVC frame it is divided into 10cm x 10cm squares, each square representing 1% of the total cover. However, there are only nine squares within the frame, hence the name “niner.” A plexidec can help determine the cover of vegetative units with covers less than 1%. Plexidecs are clear plastic squares that are held above vegetation. Each plexidec represents a cover of 0.5% and has smaller dimensions etched onto the surface that correspond to 0.01%, 0.05%, 0.1%, and 0.25% cover.It is extremely important that cover and height measurements remain consistent over time to ensure that regressions based on this data remain valid. Field crew members should calibrate with each other to ensure that observer bias does not influence data collectionCover Measurements:Grasses-To determine the cover of a grass clump, envision a perimeter around the central mass or densest portion of the plant, excluding individual long leaves, wispy ends, or more open upper regions of the plant. Live foliage is frequently mixed with dead foliage in grass clumps and this must be kept in mind during measurement as our goal is to measure only plant biomass for the current season. In general, recently dead foliage is yellow and dead foliage is gray. Within reason, try to include only yellow or green portions of the plant in cover measurement while excluding portions of the plant that are gray. This is particularly important for measurements made in the winter when there is little or no green foliage present. In winter, sometimes measurements will be based mainly on yellow foliage. Stoloniferous stems of grasses that are not rooted should be ignored. If a stem is rooted it should be recorded as a separate observation from the parent plant.Forbs-The cover of forbs is measured as the perimeter of the densest portion of the plant. If the forb is an annual it is acceptable to include the inflorescence in this measurement. If the forb is a perennial, do not include the inflorescence as part of the cover measurement. Measure all foliage that was produced during the current season, including any recently dead (yellow) foliage. Avoid measuring gray foliage that died in a previous season.Cacti-For cacti that consist of a series of pads or jointed stems (Opuntia phaecantha, Opuntia imbricata) measure the length and width of each pad to the nearest cm instead of cover and height. Cacti that occur as a dense ball/clump of stems (Opuntia leptocaulis) are measured using the same protocol as shrubs. Pincushion or hedgehog cacti (Escobaria vivipara, Schlerocactus intertextus, Echinocereus fendleri) that occur as single (or clustered) cylindrical stems are measured as a single cover.Yuccas-Make separate observations for the leaves and caudex (thick basal stem). Break the observations into sections of leaves that are approximately the same height and record the cover as the perimeter around this group of leaf blades. The caudex is measured as a single cover. The thick leaves of yuccas make it difficult to make a cover measurement by centering yourself over the caudex of the plant. The cover of the caudex may be estimated by holding a niner next to it or using a tape measure to measure to approximate the area.Height Measurements:Height is recorded as a whole number in centimeters. All heights are vertical heights but they are not necessarily perpendicular to the ground if the ground is sloping.Annual grasses and all forbs-Measure the height from the base of the plant to the top of the inflorescence (if present). Otherwise, measure to the top of the green foliage.Perennial grasses-Measure the height from the base of the plant to the top of the live green foliage. Do not include the inflorescence in the height measurement. The presence of live green foliage may be difficult to see in the winter. Check carefully at the base of the plant for the presence of green foliage. If none is found it may be necessary to pull the leaf sheaths off of several plants outside the quadrat. From this you may be able to make some observations about where green foliage is likely to occur.Perennial shrub and sub-shrubs-Measure the height from the base of the green foliage to the top of the green foliage, ignoring all bare stems. Do not measure to the ground unless the foliage reaches the ground. Plants rooted outside but hanging into a quadrat-Do not measure the height from the ground. Measure only the height of the portion of the plant that is within the quadrat.Recording the Data:Excel spreadsheets are used for data entry and file names should begin with the overall study (npp), followed by the date (mm.dd.yy) and the initials of the recorder (.abc). The final format should be as follows: npp_flux.mm.dd.yy.abc.xls. File names should be in lowercase.
Data Table:
Entity Name: sev253_nppfluxquadrat_20150819.txt
Entity Description: Data for sev253, biome transition along elevational gradients NPP study.
Object Name: sev253_nppfluxquadrat_20150819.txt
Data Format:
Text Format:
Number of Header Lines: 1
Record Delimiter: \r\n
Attribute Orientation: column
Simple Delimited:
Field Delimiter: ,
Distribution:
Online:
URL: https://pasta.lternet.edu/package/data/eml/knb-lter-sev/253/219268/3f4820b8f6e2eb01f294cf2968ebe909
Coverage:
Temporal Coverage:
Date Range:
Begin Date:
Calendar Date: 2011-05-04
End Date:
Calendar Date: 2014-10-08
Attribute List:
Attribute Name: year
Attribute Label: year
Attribute Definition: The year in which data was collected.
Storage Type: date
Measurement Scale:
Datetime:
Format String: YYYY
Attribute Name: season
Attribute Label: season
Attribute Definition: The season in which data was collected.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Enumerated Domain:
Code Definition:
Code: 1
Definition: winter
Code Definition:
Code: 2
Definition: spring
Code Definition:
Code: 3
Definition: fall
Attribute Name: date
Attribute Label: date
Attribute Definition: The date on which data or a sample was collected.
Storage Type: date
Measurement Scale:
Datetime:
Format String: MM/DD/YY
Attribute Name: site
Attribute Label: site
Attribute Definition: The site at which data was collected for sev 253, the Biome Transition Along Elevational Gradients in New Mexico Net Primary Productivity (NPP) Study.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Enumerated Domain:
Code Definition:
Code: Burn03
Definition: This site was burned in 2003 and is designated "control."
Code Definition:
Code: Burn09
Definition: This site was burned in 2009 and is designated "burned."
Attribute Name: treatment
Attribute Label: treatment
Attribute Definition: The treatment applied to a site.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Enumerated Domain:
Code Definition:
Code: B
Definition: burned
Code Definition:
Code: C
Definition: control
Attribute Name: quad
Attribute Label: quad
Attribute Definition: The quadrat at which data was collected.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Text Domain:
Definition: The quadrat at which data was collected.
Attribute Name: species
Attribute Label: species
Attribute Definition: The Kartez code for a plant species as designated by the USDA Plants Database.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Text Domain:
Definition: The Kartez code for a plant species as designated by the USDA Plants Database.
Attribute Name: obs
Attribute Label: obs
Attribute Definition: The sequential number given to a specific vegetative unit within a quadrat.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Text Domain:
Definition: The sequential number given to a specific vegetative unit within a quadrat.
Attribute Name: cover
Attribute Label: cover
Attribute Definition: The percent cover of an observation (or vegetative unit) for a given species.
Measurement Scale:
Ratio:
Unit:
Custom Unit: percentage
Numeric Domain:
Number Type: real
Bounds:
Minimum: 0.01
Maximum: 100
Attribute Name: height
Attribute Label: height
Attribute Definition: The height of an observation (or vegetative unit) for a given species. For grasses, this is the average height of green foliage. For herbs, it includes the inflorescence, if applicable.
Measurement Scale:
Ratio:
Unit:
Standard Unit: centimeter
Precision: 1
Numeric Domain:
Number Type: real
Attribute Name: count
Attribute Label: count
Attribute Definition: The number of records within a vegetative unit for a given species.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Text Domain:
Definition: The number of records within a vegetative unit for a given species.
Attribute Name: comments
Attribute Label: comments
Attribute Definition: A special statement related to an observation.
Storage Type: string
Measurement Scale:
Nominal:
Non Numeric Domain:
Enumerated Domain:
Code Definition:
Code: na
Definition: not applicable