This files presents all of the flux data post-EdiRe processing at 30 minute resolution. Included in this file is: Ux = Mean wind speed in the x-direction, Uy = mean wind speed in the y-direction, Uz = mean wind speed in the z-direction, Co2 = CO2 atmospheric concentrations, H2O = Water atmospheric concentrations, Press = barometric pressure, Air Temp = atmospheric temperature, wind speed = mea
n wind speed towards 216 degrees from north, H Flux = sensible heat flux, LE Flux = latent heat flux, C Flux = carbon flux.
The seasonal variability in rainfall duration, intensity, and volume due to the North American Monsoon Season (NAMS) has been well documented in southwestern American semiarid landscapes. The char
acteristic high intensity convective NAMS storm systems during the months of June-September lead to a greatly altered land surface in terms of soil moisture and vegetation. However, large-scale investigation of the effects of land-surface changes on hydrometeorological processes within the NAMS region has minimal associated research to this point. It is our objective to characterize the Tromble Weir watershed within the Jornada Experimental Range in order to better understand the role of land surface conditions on the propagation of the NAMS. In particular, this study investigates the impact of land-surface heterogeneity on eddy covariance tower measurements. We rely on the use of an eddy covariance tower present at the Tromble Weir watershed as well as a series of soil moisture and temperature probes under various land surface conditions distributed in the area near the tower. This study will assess and improve the implementation of the eddy covariance technique in heterogeneous landscapes like those at the Jornada Experimental Range.
This research includes 3 hydrometeorological stations, 3 H-flumes with pressure transducers, and one meteorological flux tower. Hillslope transects are run from each of the hydrometeorological stations in order to assess local spatial variations in soil moisture and temperature. The equipment deployments utilized in this study will allow for watershed scale characterization of soil energy flux, rainfall, soil moisture, and streamflow, and how feedbacks between these parameters and seasonal land cover changes in vegetation are affected by NAMS hydrometeorological processes. This study is the first of a multi-year watershed characterization project which will include 3 separate watersheds1 over 5 consecutive summers. The deployment of this dense observation network in multiple semi-arid basins will allow for cross-NAMS region comparisons of hydrometeorological responses to the seasonal evolution of land-cover changes through the application of a coupled hydrometeorological modeling system. It will also allow for the forecasting of how land-surface may change the hydrometeorological responses of basins within the NAMS region.
1We will be focusing on primarily three sites: at the Jornada, at the Santa Rita Experimental Range in southern Arizona, and at the Sevilleta National Wildlife Refuge in southern New Mexico.
Rainfall simulation experiments were performed in aras of semiarid grassland (Boutelous eriopoda) and arid shrubland (Larrea tridentata).
The objective was to compare the runoff of nitrogen (N) and phosphorus (P) from these habitats to assess whether losses of soil nutrients are associated with the invasion of grasslands by shrubs.
Looking at infiltration and runoff rates as related to rain event duration and intensity as well as soil and organic movement as related below in creosotebush and grassland areas.
Nine hydrology runoff plots were begun in 1983 during LTER-I and located in creosotebush zone. An additional 12 runoff plots have been added. These additions consist of 4 each at C-CALI, G-SUMM, and G-IBPE. G-SUMM and G-IBPE are blackgrama grassland sites. Refer to LTER site map for locations. Water runoff was collected from individual natural rain events off 2x2m plots. C-TERM consists of 8 plots. Plots C1-C4 are untreated. Plots T1-T5 were previously treated with chlordane to remove termites. Each of the 4 sets of run off plots at all sites can be divided into 2 low cover and 2 high cover plots (for creosotebush zone, these are with and without creosotebush shrubs). Data collected: relative cover, runoff, suspended sediment, precipitation, deposited sediment, percent carbon of deposited sample, water chemistry.
On 10/27/89, 03/14/90, and 10/19/90, % plant cover by species was measured on 20 2x2m hydrology run off plots using quadrats with 10x10cm units.
Site identification follows: ZONE C - creosotebush; G - grassland SITE CALI-HYD Caliche site - Hydrology study TERM-HYD Termite +/- site - Hydrology study IBPE-HYD IBPE site - Hydrology study SUMM-HYD Summerford site - Hydrology study PLOT CALI-HYD, IBPE-HYD, & SUMM-HYD each have 4 run off plots numbered 1-4. TERM-HYD has 8 plots; 4 control (C1-C4) and 4 treatment (T2-T5). Treatment was with Chlordane to eliminate termites in soil.
The data consists of chemical analyses of dissolved ions in samples of surface runoff from natural rainfall events collected from experimental hydrology plots in creosotebush scrub and grass- land areas of the New Mexico State University Ranch and USDA Jornada Experimental Range.
Chemical analyses are for F, Cl, NO3, SO4 by ion chromatography, NH4 by autoanalyzer, Ca, Mg, Na, K by atomic absorption spectrophotometry, and total N and P by auto- analyzer.
OVERVIEW This is the Jornada Long Term Ecological Research site data base for the 2 x 2 meter natural rainfall-runoff plots. There are 4074 plot-events or observations in the data set. Of those 4074 observations, 2745 contained precipitation values greater than zero or contained precipitation values greater than runoff values.
Very few observations showed runoff values greater than precipitation. All values are included here for completeness of the data set. These data were collected and analyzed in the laboratory under the supervision of John Anderson (primarily). Dr. Susan M. Bolton and Dr. Tim J. Ward compiled and checked the data. Tim J. Ward is responsible for the final input, checking and presentation of the data set presented below. Questions about the data should be directed to Tim J. Ward through the Jornada LTER.