Summary Information
Effects of Multiple Resource Additions on Community and Ecosystem Processes: NutNet NPP Quadrat Sampling at the Sevilleta National Wildlife Refuge, New Mexico (2007-present)
Creator: Individual: Scott Collins Organization: SEV LTER Physical Address: Delivery Address: Department of Biology, MSC03 2020, 1 University of New Mexico City: Albuquerque Locality: NM Postal Code: 87131 Email: scollins@sevilleta.unm.edu System ID: 12275
Associated Party: Individual: Amaris Swann Organization: SEV LTER Physical Address: Delivery Address: , Postal Code: 0 Phone: (505) 277-8119 Email: amswann@sevilleta.unm.edu System ID: 15021 Role: data manager
Associated Party: Individual: Sevilleta LTER Field Crew Sevilleta LTER Field Crew Organization: SEV LTER Email: data-use@sevilleta.unm.edu Role: field crew
Associated Party: Individual: Laura Calabrese Organization: SEV LTER Physical Address: Delivery Address: University of New Mexico, Department of Biology, MSC 03 2020 City: Albuquerque Locality: NM Postal Code: 87131 Phone: US Email: laura@sevilleta.unm.edu System ID: 13985 Role: field crew
Publication Date:	2015
Language:	english
Abstract: Two of the most pervasive human impacts on ecosystems are alteration of global nutrient budgets and changes in the abundance and identity of consumers. Fossil fuel combustion and agricultural fertilization have doubled and quintupled, respectively, global pools of nitrogen and phosphorus relative to pre-industrial levels. In spite of the global impacts of these human activities, there have been no globally coordinated experiments to quantify the general impacts on ecological systems. This experiment seeks to determine how nutrient availability controls plant biomass, diversity, and species composition in a desert grassland. This has important implications for understanding how future atmospheric deposition of nutrients (N, S, Ca, K) might affect community and ecosystem-level responses. This study is part of a larger coordinated research network that includes more than 40 grassland sites around the world. By using a standardized experimental setup that is consistent across all study sites, we are addressing the questions of whether diversity and productivity are co-limited by multiple nutrients and if so, whether these trends are predictable on a global scale.
Keywords: Keyword: inorganic nutrients Keyword: populations Keyword: primary production Keyword Thesaurus: Core Areas
Keywords: Keyword: species Keyword: measurements Keyword: productivity Keyword: seasonality Keyword: nutrients Keyword: plants Keyword: foliage Keyword: grasses Keyword: vegetation Keyword: stems Keyword Thesaurus: LTER Controlled Vocabulary
Additional Information: Additional Information on the Data Collection PeriodSpecies composition and net primary production was sampled semiannually (spring and fall) in 2007, 2008, and 2009. Soil was sampled and analyzed in the fall in 2007 and 2008. Plots were fertilized annually starting in 2008.In August 2009, a wildfire burned all 40 of the NutNet plots causing no Fall 2009 vegetation measurements.Special Codes for Vegetation Ids:SPORSP- Unknown SporobolusSPSP- Unknown SphaeralceaUNKFO- Unknown ForbOn 08/20/2015, the following taxonomic changes were made to the data: ARPUP6 was changed to ARPU9, OECAC2 was changed to OECA10, SPWR was changed to SPPO6
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/2304
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: 2007-05-01 End Date: Calendar Date: 2015-04-23
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: Information Manager Sevilleta LTER Organization: SEV LTER Physical Address: Delivery Address: 1 University of New Mexico City: Albuquerque Postal Code: 87131 Phone: (505) 277-2109 Phone: (505) 277.5355 Email: data-use@sevilleta.unm.edu
Publication Place:	Sevilleta LTER
Method Step: Description: Methods: Nutrient addition treatments and sampling sites are located in an area of desert grassland dominated by black grama, Bouteloua eriopoda. The experimental design is completely randomized with 8 treatments replicated 5 times each.  The nutrients added include N (nitrogen), P (phosphorus), and K (potassium plus other nutrients). Treatments are: +N+P+K, +N+P, +N+K, +N, +P+K, +P, +K, and control (no nutrients added).  Treatments were randomly assigned to 40-25 m2 plots with 1m separating each plot. Response variables measured include: plant community composition; percent ground cover of live perennial grasses, herbaceous dicots, shrubs, cactus, litter, and bare ground; aboveground net primary production; light availability, and several soil parameters (moisture, organic matter content, pH, P, field available nitrogen (NO3-N and NH4-N), potentially mineralizable N).This experiment was initiated in May 2007 with one year of pre-treatment data and 3 years of post-treatment data collected thus far.  Nutrients are applied annually at the beginning of the growing season starting in 2008.  Plant community composition, percent cover of individual plant species, and aboveground net primary production will continue to be monitored semiannually (spring and fall) in a permanently marked 1m2 subplot in each plot. Soil will be collected each year and will be shipped to collaborators for analyses. Net Primary Productivity (NPP) Measurements                               Collecting the Data:Net primary production data is collected twice 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. Winter measurements are taken in February before the onset of spring growth.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.Niners and plexidecs are additional tools that 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 collection.In 2013, percent cover of litter and bare soil were added for each quadrat.Cover 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 average length and width of each pad 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). Finally, the site abbreviation should be added (i.e., c, g, b, p). The final format should be as follows: npp.mm.dd.yy.abcg.xls. File names should be in lowercase.
Quality Control: Description: All data were QA/QC'd by use of filters in Excel and imported into MySQL.
Data Table: Entity Name: sev231_nppnutnetquadrat_20150820.txt Entity Description: Data for nutnet ANPP quadrat sampling for the years 2008-2013. Object Name: sev231_nppnutnetquadrat_20150820.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/231/176381/86f4be468b1db075b6a04724908db912 Coverage: Temporal Coverage: Date Range: Begin Date: Calendar Date: 2008-05-13 End Date: Calendar Date: 2014-08-28 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. Storage Type: string Measurement Scale: Nominal: Non Numeric Domain: Enumerated Domain: Code Definition: Code: N Definition: Nutritent Network site, located within Deep Well blue/black grama mixed grassland. Attribute Name: treatment Attribute Label: treatment Attribute Definition: The fertilizer regime applied to a quadrat for the Nutrient Network project (SEV231). Storage Type: string Measurement Scale: Nominal: Non Numeric Domain: Enumerated Domain: Code Definition: Code: NPK Definition: Nitrogen, phosphorus, and potassium added. Code Definition: Code: NP Definition: Nitrogen and phosphorus added. Code Definition: Code: NK Definition: Nitrogen and potassium added. Code Definition: Code: N Definition: Nitrogen added. Code Definition: Code: PK Definition: Phosphorus and potassium added. Code Definition: Code: P Definition: Phosphorus added. Code Definition: Code: K Definition: Potassium added. Code Definition: Code: C Definition: Control/no fertilizer. 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