DSL2002046 SEASMEAN Jornada Basin LTER

NMSU, Wooton Hall, Room 200 2995 Knox Street, Room 200 Box 30003, MSC 3JER Las Cruces NM 88003

(505) 646-7918 (505) 646-5889 datamanager@jornada.nmsu.edu http://jornada-www.nmsu.edu Dr. Laura F Huenneke Jornada Basin LTER

Dean, College of Arts & Sciences Northern Arizona University P.O. Box 5621 Flagstaff AZ 86011-5621

928-523-0516 Laura.Huenneke@nau.edu ORG0000001 Dr. Laura F Huenneke Jornada Basin LTER

Dean, College of Arts & Sciences Northern Arizona University P.O. Box 5621 Flagstaff AZ 86011-5621

928-523-0516 Laura.Huenneke@nau.edu Researcher English Deserts and semi-deserts are characterized as ecosystems of low primary productivity, but a more pertinent trait is the variability of plant production in space and time. In dryland ecosystems there are usually some locations on the landscape (e.g., sites receiving run-on moisture from adjacent areas) and some time periods where plant growth is lush in response to temporary favorable conditions. Our objective in monitoring net primary production, therefore, is to understand the temporal and spatial patterns of production within ecosystems as well as to characterize the relative productivity of various ecosystems. Our chief questions pertain to the impact of desertification (shrub encroachment in former semi-arid grasslands) on patterns of production. First, can we detect significant differences in productivity between shrub-dominated and grass-dominated systems? Second, given our evidence for greater spatial heterogeneity in soil resources at the plant scale in shrub systems, how does the spatial heterogeneity of aboveground production compare among ecosystems? Finally, how do seasonal and interannual patterns of plant production response to climate vary among ecosystems? Our methodology for measuring aboveground net primary production has been adopted to allow explicit comparison of production among ecosystems of different structure and to facilitate assessment of spatial variation. We have designed a non-destructive method that samples vegetation of different structures with consistent methodology and intensity of sampling, and that allows the quantification of NPP for particular unit areas such that one can characterize spatial patterns in NPP. In early 1989 grids of permanent 1 m2 quadrats were established in 15 sites: 3 each in Larrea shrubland, Bouteloua eriopoda grassland, Prosopis dune systems, Flourensia cernua alluvial flats, and grass-dominated dry lakes or playas. Sites were selected to represent the range of biomass and vegetation structure within each ecosystem type, rather than randomly selected among sites of that ecosystem type in the basin (Figure 1). Aboveground biomass is estimated for every species in 49 quadrats per site, three times per year, using non-destructive measures of plant size and applying regressions based on harvests from adjoining areas. These data provide quantitative measures of the abundance of all vascular plant species at each site every season. Productivity over an interval for a quadrat is estimated as the sum of all positive increments of biomass for all species in that quadrat. At each of the 15 sites we are also measuring soil moisture (via neutron probe) monthly. Rain gauges at each site provide localized precipitation data to accompany weather data from the central meteorological station. Chihuahuan Desert Las Cruces NM Southwest USA Dona Ana County JRN Jornada Basin LTER LTER plant biomass vegetation seasonality

This dataset is released to the public and may be used for academic, educational, or commercial purposes subject to the following:

The Jornada Basin LTER Information Management System provides protocol and services for data collection, verification, organization, archives, and distribution.

Data managers interact with researchers during the entire scientific process--from the initial planning of sampling designs and field data collection to archiving and distribution of long-term data. The goal of data management is to build and maintain an archive of Jornada Basin LTER data files that are fully documented, error free, and organized in useful ways. Our protocol for data collection and processing seeks maximum interaction between researchers and data management personnel to avoid confusion and potential loss of data or problems with integrity of data. The data manager helps researchers to construct data forms that allow convenient data entry and analysis. Data documentation forms are completed by principal investigators prior to data entry. Data are entered into computer data files by data entry personnel using programs that error- check and verify the data as it is entered. Computer files are subjected to further verification by graphing and/or error-checking programs, and/or examination by field investigators. Error-checked data files are stored with associated documentation files on floppy disks and on a hard-disk database. Back-up data files are maintained as "hard-copy," on multiple floppy disks, and on read/write 30- year magneto-optical disks. Various sets of these data are stored at different sites on the NMSU campus. The final responsibility for quality assurance (both in data and documentation content) rests with the principal investigator who submits the data for inclusion in the Jornada Basin LTER Information Management System. To facilitate quality assurance, the data management staff will provide copies of data and documentation submitted by a principal investigator to that investigator upon request.

All data collected during a calendar year should be submitted to the Jornada Basin LTER data manager prior to July first of the following year. Data must be submitted with standard Jornada Basin LTER forms (both Project Abstract and Data Set documentation) which include objectives of the study, methods, as well as format and content of the data.

Data will be made publicly available no later than 2 years after submission of the data unless an earlier date is specified by the principal investigator. In the event that an extension of the 2 year period is necessary, the principal investigator may petition the Jornada Basin LTER Executive Committee for a longer protected period.

Individuals and institutions utilizing data from the Jornada Basin LTER database are requested to place the following acknowledgment in any publication in which these data are mentioned: Data sets were provided by the Jornada Basin Long-Term Ecological Research (LTER) projects. Funding for these data was provided by the U.S. National Science Foundation (Grants DEB-92-40261 and DEB 94-11971). Please send 1 copy of any publication that cites Jornada Basin LTER data to: John P. Anderson Jornada Experimental Range P.O. Box 30003, MSC 3JER New Mexico State University Las Cruces, NM 88003-0003

http://jornada-www.nmsu.edu/datacat.htm Jornada Basin,Chihuahuan Desert, 17 miles NE of Las Cruces, NM, USA -107.002148 -106.502641 32.831393 32.428919 1188 2658 meter 1989-04-01 ongoing Three times per year, February, May, and October

Three times per year, February, May, and October

Data set title - Seasonal mean aboveground biomass, SUMMARYData set file name - SEASMEAN.DSD----------------------------------------------------------------mm/dd/yyyy - Date of CommentInt - Initials of person making CommentJPA = John P. AndersonJL = Jim LenzLH = Laura HuennekeKR = Ken RamseyChanges/Updates - List any changes made to documentmm/dd/yyyy Int Changes/Updates---------- --- -----------------------------------------------06/23/1997 LFH Form completed by investigator01/14/1998 JPA Documentation transferred to new form12/01/1998 JPA Added comment06/13/2002 JL Added Dataset ID and Project ID sections.07/15/2004 JPA Updated list of Other Files to reflect updateddata set by LH. Updated Attributes to reflectdata transformation noted in Comments section.08/31/2004 KR Changed format for Attributes and AssociatedFiles section.Moved Dataset and Project IDs to top of form.Removed Missing/Questionable data section andincorporated into Attributes section.Updated Associated Files section.05/06/2005 KR Added NPP Regression compressed file toAssociated Files section.01/30/2006 KR Added start column position numbers for all attributes.-------------------------------------------------------------------

Data Manager

NMSU, Wooton Hall, Room 200 2995 Knox Street, Room 200 Box 30003, MSC 3JER Las Cruces NM 88003

(505) 646-7918 (505) 646-5889 datamanager@jornada.nmsu.edu http://jornada-www.nmsu.edu Data Manager

NMSU, Wooton Hall, Room 200 2995 Knox Street, Room 200 Box 30003, MSC 3JER Las Cruces NM 88003

(505) 646-7918 (505) 646-5889 datamanager@jornada.nmsu.edu http://jornada-www.nmsu.edu Debra Peters

USDA-ARS Jornada Experimental Range P.O. Box 30003, MSC 3JER New Mexico State University Las Cruces NM 88003-0003

505 646 2777 505 646 5889 debpeter@nmsu.edu ORG0000001 ----------------------------------------------------------------Field sampling described in project documentation. Analysis ofaboveground biomass by species described in documentation forplant biomass datasets (NQBIOxxy DAT). Biomass of all speciesin a quadrat summed, then total biomass per quadrat averagedfor the 49 quadrats within a site.

DWREG.SAS used to produce regressions from harvest data;NQBIOxxy.SAS used to produce biomass by species by quadrat fora given sample date;PROD.SAS used to calculate productivity for individual quadratsfrom two successive NQBIOxxy.DAT files, and to summarizeby calculating averages per site.

Mr. Justin B Jensen

New Mexico State University Jornada Basin LTER Box 30003, MSC 3JER Las Cruces NM 88003-8003

Post doctoral associate Dr. Laura F Huenneke

Dean, College of Arts & Sciences Northern Arizona University P.O. Box 5621 Flagstaff AZ 86011-5621

928-523-0516 Responsible Investigator Dr. Debra P Peters

USDA-ARS Jornada Experimental Range P.O. Box 30003, MSC 3JER New Mexico State University Las Cruces NM 88003-0003

505 646 2777 Principal Investigator funding the research Dr. Laura F Huenneke

Dean, College of Arts & Sciences Northern Arizona University P.O. Box 5621 Flagstaff AZ 86011-5621

928-523-0516 Principal Investigator funding the research John Anderson

New Mexico State University Jornada Basin LTER Box 30003, MSC 3JER Las Cruces NM 88003-8003

505-646-5818 Additional Investigator Esteban Muldavin

Additional Investigator Deserts and semi-deserts are characterized as ecosystems of low primary productivity, but a more pertinent trait is the variability of plant production in space and time. In dryland ecosystems there are usually some locations on the landscape (e.g., sites receiving run-on moisture from adjacent areas) and some time periods where plant growth is lush in response to temporary favorable conditions. Our objective in monitoring net primary production, therefore, is to understand the temporal and spatial patterns of production within ecosystems as well as to characterize the relative productivity of various ecosystems. Our chief questions pertain to the impact of desertification (shrub encroachment in former semi-arid grasslands) on patterns of production. First, can we detect significant differences in productivity between shrub-dominated and grass-dominated systems? Second, given our evidence for greater spatial heterogeneity in soil resources at the plant scale in shrub systems, how does the spatial heterogeneity of aboveground production compare among ecosystems? Finally, how do seasonal and interannual patterns of plant production response to climate vary among ecosystems? Our methodology for measuring aboveground net primary production has been adopted to allow explicit comparison of production among ecosystems of different structure and to facilitate assessment of spatial variation. We have designed a non-destructive method that samples vegetation of different structures with consistent methodology and intensity of sampling, and that allows the quantification of NPP for particular unit areas such that one can characterize spatial patterns in NPP. In early 1989 grids of permanent 1 m2 quadrats were established in 15 sites: 3 each in Larrea shrubland, Bouteloua eriopoda grassland, Prosopis dune systems, Flourensia cernua alluvial flats, and grass-dominated dry lakes or playas. Sites were selected to represent the range of biomass and vegetation structure within each ecosystem type, rather than randomly selected among sites of that ecosystem type in the basin (Figure 1). Aboveground biomass is estimated for every species in 49 quadrats per site, three times per year, using non-destructive measures of plant size and applying regressions based on harvests from adjoining areas. These data provide quantitative measures of the abundance of all vascular plant species at each site every season. Productivity over an interval for a quadrat is estimated as the sum of all positive increments of biomass for all species in that quadrat. At each of the 15 sites we are also measuring soil moisture (via neutron probe) monthly. Rain gauges at each site provide localized precipitation data to accompany weather data from the central meteorological station. Dr. Debra Peters

USDA-ARS Jornada Experimental Range P.O. Box 30003, MSC 3JER New Mexico State University Las Cruces NM 88003-0003

505 646 2777 PE00000002 Information Manager Historical Perspective: The Chihuahuan Desert , similar to many arid and semiarid ecosystems of the world, has experienced dramatic changes in vegetation structure and ecosystem processes over the past several centuries. The reasons for the expansion of woody plants and decrease in perennial grasses are numerous and controversial, including livestock grazing, drought, climate change, reduction in fire frequency, and change in small animal populations. The problem is further complicated by the existence of interactions among these factors that feature positive feedbacks and that create threshold behavior and nonlinearity in ecosystem responses. A general consensus does not exist regarding the key factors that control the desertification process or the conditions that explain varying patterns of shrub invasion or grass persistence under similar conditions. It is also unclear why many attempts to remediate shrublands back to grasslands have failed whereas some methods have worked well, but with long time lags. Site History: The Jornada Basin Long Term Ecological Research Program (JRN LTER), supported by major funding from the National Science Foundation, has been investigating desertification processes since 1982. We benefit from a legacy of long-term data available from 1912 onwards, thanks to collaboration with our research partner, the Jornada Experimental Range Agricultural Research Service (JER ARS). Significant progress has been made in understanding the causes and consequences of desertification, although important problems still remain. In particular, several key questions are unresolved, including (1) can we predict spatial and temporal variation in ecosystem properties related to desertification and grass recovery? (2) how do we integrate diverse observations about vegetation, climate, soils, hydrology, and animal populations to accomplish this prediction? This integration is the focus of current LTER studies. Research Topics: desertification; ecosystem indicators and vegetation dynamics; geomorphology and wind; ecohydrology; animal interactions; factors affecting primary production; animal-induced soil disturbances; direct and indirect consumer effects; vertebrate and invertebrate population dynamics; grazing effects on ecosystem structure and function; biodiversity and ecosystem. Jornada Basin Climate and Vegetation NSF Award DEB-0080412 description. U.S. National Science Foundation (Grant DEB-0080412) uid=JRN,o=lter,dc=ecoinformatics,dc=org all public read SEASMEAN.SUM Data file SEASMEAN.SUM column 3 1 6 9 4 20 date date Season and year of field measurements syy, where s=season of field measurements (W=winter, S=spring, F=fall) and yy = year Character site site Vegetation zone and research site <z-ssss>, where z = vegetative zone (C=creosotebush, G=grassland, M=mesquite dune, P=playa, t=tarbush) and ssss = research site (CALI=caliche, GRAV=gravel, SAND=sand, BASN=basin, IBPE=IBP exclosure, SUMM=Mt. Summerford, NORT=north, RABB=rabbit, WELL=well, COLL=college, SMAL=small, TOBO=tobosa tank, EAST=east, TAYL=taylor, WEST=west) Character biomass biomass aboveground live biomass, summed for all species, averaged across all quadrats within a site. Integer <NPPQsyy.DAT> <NPPQsyy.DAT>, where s=season and yy=year. One data file for each sample season; these are field data giving cover and height measurements for each plant or plant part in each quadrat, File Format: ASCII, File Type: Text file <NPPQsyy.DAT> ASCII Text file Other <NQBIOyys.DAT> <NQBIOyys.DAT>, where yy=year and s=season. Each of these is summary of biomass, by species, by quadrat, for a given date., File Format: ASCII, File Type: Text file <NQBIOyys.DAT> ASCII Text file Other <NQBIOyys.SAS> <NQBIOyys.SAS>, where yy=year and s=season. SAS program used to process NPPQxxy.DAT (field data files), File Format: ASCII, File Type: Text file <NQBIOyys.SAS> ASCII Text file Data entry, verification, and analysis file NppBiomassCalculations.zip NPP Regression coefficients and SAS procedures for calculating NPP biomass, File Format: ASCII, File Type: Text file NppBiomassCalculations.zip ASCII Text file Data entry, verification, and analysis file NPPHARV.DSD NPP reference harvest data, File Format: ASCII, File Type: Text file NPPHARV.DSD ASCII Text file Other NPPSITE.SAS SAS program used to summarize NQBIOxxy.DAT to produce summary statistics per site for a sample date, File Format: ASCII, File Type: Text file NPPSITE.SAS ASCII Text file Data entry, verification, and analysis file NPPVEG.PRJ Project documentation, File Format: ASCII, File Type: Text file NPPVEG.PRJ ASCII Text file Metadata file PLNTALFA.LST Jornada plant species list, File Format: ASCII, File Type: Text file PLNTALFA.LST ASCII Text file Other SEASMEAN.DSD Data set documentation, File Format: ASCII, File Type: Text file SEASMEAN.DSD ASCII Text file Metadata file