uid=SEV,o=LTER,dc=ecoinformatics,dc=org all public read William Pockman SEV LTER

Department of Biology, MSC03 2020, 1 University of New Mexico Albuquerque NM 87131

pockman@unm.edu 12857 Nathan McDowell SEV LTER

Earth and Environmental Sciences, LANL Los Alamos NM

mcdowell@lanl.gov Nathan Gehres SEV LTER gehresn@hotmail.com data manager english

Climate models predict that water limited regions around the world will become drier and warmer in the near future, including southwestern North America. We developed a large-scale experimental system that allows testing of the ecosystem impacts of precipitation changes. Four treatments were applied to 1600 m2 plots (40 m × 40 m), each with three replicates in a piñon pine (Pinus edulis) and juniper (Juniper monosperma) ecosystem. These species have extensive root systems, requiring large-scale manipulation to effectively alter soil water availability.  Treatments consisted of: 1) irrigation plots that receive supplemental water additions, 2) drought plots that receive 55% of ambient rainfall, 3) cover-control plots that receive ambient precipitation, but allow determination of treatment infrastructure artifacts, and 4) ambient control plots. Our drought structures effectively reduced soil water potential and volumetric water content compared to the ambient, cover-control, and water addition plots. Drought and cover control plots experienced an average increase in maximum soil and air temperature at ground level of 1-4° C during the growing season compared to ambient plots, and concurrent short-term diurnal increases in maximum air temperature were also observed directly above and below plastic structures. Our drought and irrigation treatments significantly influenced tree predawn water potential, sap-flow, and net photosynthesis, with drought treatment trees exhibiting significant decreases in physiological function compared to ambient and irrigated trees. Supplemental irrigation resulted in a significant increase in both plant water potential and xylem sap-flow compared to trees in the other treatments. This experimental design effectively allows manipulation of plant water stress at the ecosystem scale, permits a wide range of drought conditions, and provides prolonged drought conditions comparable to historical droughts in the past – drought events for which wide-spread mortality in both these species was observed.A micrometeorological station was used to document the climatic conditions at the study site.  Monitoring the ambient environment in this way allowed us to more easily determine which tree growth responses were driven by changes in the native climate as opposed to those resulting from the rainfall manipulation treatments.  Environmental factors such as temperature, relative humidity, and photosynthetically active radiation (PAR) have a huge impact on the physiological processes that are being explored in this project.  The data collected by the station created a local climatic record which was needed to provide the context in which the treatment effects can be examined and sensor readings can be interpreted.

inorganic nutrients populations Core Areas communities community structure plant communities populations species meteorology biology physiology plant physiology plant ecology events disturbances droughts measurements precipitation rain temperature methods field methods mortality tree mortality ecosystems forest ecosystems organisms plants trees LTER Controlled Vocabulary

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.

http://sev.lternet.edu/node/6825 Location: The Cerro Montosa Pinyon-Juniper site has been the location of major Sevilleta LTER research since 1989. Meteorological trends, net primary productivity, rodent and ground-dwelling arthropod populations, mycorrhizal responses to fertilizer, pinyon-juniper fruit and nut production, and pinyon mortality are all being investigated at this site. Previous studies have included analyses of pinyon tree rings for regional climate reconstruction.Vegetation: The vegetation is New Mexico Pinyon-Juniper Woodland, dominated by Colorado pinyon (Pinus edulis) and one-seed juniper (Juniperus monosperma), and accompanied by gray oak (Quercus grisea). There is a diverse shrub component, including scrub live oak (Q. turbinella), mountain mahogany (Cercocarpus montanus), broom snakeweed (Gutierrezia sarothrae), sacahuista (Nolina microcarpa), red barberry (Mahonia haematocarpa), Apache plume (Fallugia paradoxa), tree cholla (Opuntia imbricata), skunkbush (Rhus trilobata), and banana yucca (Yucca baccata). Grass diversity is also high, and open spaces between trees are dominated by blue grama (Bouteloua gracilis), with hairy and sideoats grama (B. hirsuta and B. curtipendula) and black grama (B. eriopoda) also being significant. Other common grasses include purple threeawn (Aristida purpurea), wolftail (Lycurus phleoides), mountain and ring muhly (M. montanus and M. torreyi), and New Mexican porcupinegrass (Heterostipa neomexicana). Common forbs include small-flowered milkvetch (Astragalus nuttallianus), white sagebrush (Artemesia ludoviciana), Fendler’s arabis (Arabis fendleri), Fendler’s sandmat (Chamaesyce fendleri), New Mexico thistle (Cirsium neomexicanum), false pennyroyal (Hedeoma oblongifolia), bastard sage (Eriogonum wrightii), pingüe rubberweed (Hymenoxys richardsonii), large four o’clock (Mirabilis multiflora), Fendler's penstemon (Penstemon fendleri), and globemallows (Sphaeralcea hastulata and S. wrightii). , -106.535 -106.535 34.368 34.368 1976 1976 meter 2007-01-01 2009-01-01 Sevilleta Information Manager SEV LTER data-use@sevilleta.unm.edu Sevilleta LTER

 A CR-10X datalogger was used to record data from a micrometeorological tower centrally located in an open intercanopy area of the study site. This tower recorded precipitation with a Series 525 rain gauge (Texas Electronics, Dallas, TX), net radiation with a Kipp and Zonen NK-LITE net radiometer (Campbell Scientific, Logan, UT), photosynthetically active radiation (PAR) with a LI-190SA sensor (Li-Cor, Lincoln, NE), windspeed and direction monitored with a 05103-L R.M. Young wind monitor (Campbell Scientific, Logan, UT), and air temperature and RH% with a Vaisala HMP45C sensor. During winter months the rain gauge was fitted with a snow adaptor to thaw snow and record the total amount in mm rain. All met-station measurements were made at a height of 1-3 m above ground depending on the sensor array in question. 

sev273_pjmet_20130424.txt Data for SEV273. sev273_pjmet_20130424.txt 1 \r\n column , http://sev.lternet.edu/sites/default/files/data/sev-273/sev273_pjmet_20130424.txt Location: Site situated on the eastern flank of Los Pinos Mountains, approx. 3 miles south of NM state route 60, directly adjacent to the eastern boundary of the Sevillets USFWS National Refuge. Landform: Located at the base of the eastern flank of the Los Pinos Mountains. Slope varies from 0-2% in experimental plots situated in level portions of the site, with steeper grades ranging from 6-18% for plots established on hill-slopes., Soils: Soil texture analysis across the site (both hill-slope and flat/level topography) revealed surface soils that are predominately silt loam with; (1) a transition to sandy loam texture at depth, and (2) a significant percentage of coarse fragments present both at the soil surface and throughout the profile. Soil depth across the site ranges from 20 to ≥ 100 cm, with shallower soil depths occurring on hill-slopes where depth to caliche and/or bed-rock is only 20-30 cm in some instances. , Hydrology: Well drained., Vegetation: The site is a piñon pine (Pinus edulis, Engelm.) and juniper (Juniperus monosperma (Engelm.) Sarg.) woodland, with several other commonly observed woody shrub species present, notably; Mahonia spp. (algerita), Falugia paradoxa (Apache plume), Quercus turbinella (shrub live oak), and Rhus spp. (sumac). Multiple species of cacti and agave (Cylindropuntia spp., Opuntia spp., and Yucca spp.) are present, along with numerous species of perennial grasses and forbs; including an extensive inter-canopy coverage by grasses of the genus Bouteloua. , Climate: Climate records (20-yr) from a nearby Sevilleta LTER meteorological station (Cerro Montoso #42; http://sev.lternet.edu/) indicate a mean annual precipitation total of 362.7 mm/yr. The region is strongly influenced by the North American Monsoon, with a large fraction of annual precipitation occurring in July, August, and September when monsoon circulation is active. Mean annual temperature (20-yr) at this nearby LTER site was 12.78 C, with a mean July maximum of 31.08 C and a mean December minimum of 3.38 C. , -106.5294 -106.5294 34.3864 34.3864 1911 1911 meter 2006-01-01 2012-12-31 Year Year The year in which the data were collected. date YYYY Month Month The month in which data were collected. string The month in which data were collected. Day Day The numeric designation for the day of the month on which the measurement was taken. The numbers range from 1 to 31. string The numeric designation for the day of the month on which the measurement was taken. The numbers range from 1 to 31. Hour Hour The specific hour interval for which a 15 minute measurement interval was recorded. There are 24 numbers for this variable, and they range from 0 to 23. string The specific hour interval for which a 15 minute measurement interval was recorded. There are 24 numbers for this variable, and they range from 0 to 23. Minute for a given interval record Minute The specific 15-minute interval (within an hour) for which measurements were recorded. The 15-minute interval numbers include; 0, 15, 30, 45 string The specific 15-minute interval (within an hour) for which measurements were recorded. The 15-minute interval numbers include; 0, 15, 30, 45 The hour and minute time interval associated with the measurement HrMin The hour and minute designation of the time interval during which the measurement was taken. The time intervals are 15 minutes in length and range from 0 to 2345 string The hour and minute designation of the time interval during which the measurement was taken. The time intervals are 15 minutes in length and range from 0 to 2345 Day of Year Julian_day The numeric designation for the day of the year on which the measurement was taken. Values range from 1 to 365 (366 in a leap year) string The numeric designation for the day of the year on which the measurement was taken. Values range from 1 to 365 (366 in a leap year) Day of Year decimal_Julian_day Numeric expression that provides the time of day expressed as a decimal along with the calendar day of year. Example; 365.5 would represent December 31st at 12 noon string Numeric expression that provides the time of day expressed as a decimal along with the calendar day of year. Example; 365.5 would represent December 31st at 12 noon PJ_day PJ_day The numeric designation for the day that a measurement was taken since project initiation. The initial PJ day was day 1 for the project (1/1/2006) and the count does not restart at the end of the calendar year. Example; 1/1/2006 is PJ_day #1 and 12/31/2012 is PJ_day # 2557. string The numeric designation for the day that a measurement was taken since project initiation. The initial PJ day was day 1 for the project (1/1/2006) and the count does not restart at the end of the calendar year. Example; 1/1/2006 is PJ_day #1 and 12/31/2012 is PJ_day # 2557. decimal_PJ_day decimal_PJ_day A unique date/time identifier which provides the PD_day and decimal time of day in one numerical expression string A unique date/time identifier which provides the PD_day and decimal time of day in one numerical expression PJ_Timestamp PJ_Timestamp Numeric value used as a unique designator for each 15-minute measurement interval starting on 1/1/2006. The values for PJ_Timestamp currently range from 1 to 245472. string Numeric value used as a unique designator for each 15-minute measurement interval starting on 1/1/2006. The values for PJ_Timestamp currently range from 1 to 245472. Atmospheric pressure Atm_pressure The mean atmospheric pressure during the time interval when the measurement was taken. millibar 1 real Rnet Rnet The mean net radiation during the time interval when the measurement was taken. Net radiation is defined as the difference between incoming solar radiation and outgoing terrestrial radiation. It is therefore usually negative at night and positive during the daylight hours. This is net radiation in the spectral range from 200 to 100,000 nm. Units are watts per meter squared of ground area. wattsPerMeterSquared 0.01 real PAR PAR The mean amount of photosynthetically active radiation available during the time interval when the measurement was taken. Par is a measure of the amount of solar radiation that is available in the 400 to 700 nanometer wavelength range, the wavelengths plants can use for photosynthesis. micromolesPerMeterSquaredPerSecond 0.01 real Temperature Temperature The mean air temperature during the time interval when the measurement was taken. celsius 0.01 real Relative Humidity RH Relative Humidity measured at 1.75 m with 207 Temp Rel Humidity Sensor percent 0.01 real 0 100 Wind_speed Wind_speed The mean speed the wind was traveling during the time interval when the measurement was taken. meterPerSecond 0.001 real Wind direction Wind_dir The mean direction the wind was traveling during the time interval when the measurement was taken. degree 0.01 real Precipitation Precipitation The amount of precipitation collected during the time interval when the measurement was taken. millimeter 0.01 real Maximum Windspeed Max_Windspeed The maximum wind speed recorded during the time interval when the measurement was taken. meterPerSecond 0.001 real Saturated vapor pressure Vapor_pressure_sat Calculated pressure value for the point at which evaporation and condensation are in equilibrium in the system. kilopascal 0.01 real Vapor pressure Vapor_pressure Calculated value representing ambient water vapor pressure in the system. kilopascal 0.01 real Vapor pressure deficit VPD Calculated value representing the difference between saturated and ambient vapor pressures. kilopascal 0.01 real watts Per Meter Squared ratio of two quantities as percent composition (1:100) meters per second