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This dataset contains data on vegetation biomass removed from treatment plots during the establishment of a biodiversity experiment at the Jornada Basin LTER site in southern New Mexico, USA. In fall of 1995, various combinations of plant functional groups or species were experimentally removed from 25 x 25 meter plots with the objective to distinguish the differential effects of plant community biomass, functional groups, and biodiversity within functional groups on ecosystem and plant community function. Eight different treatments were established with selective removal of species or functional groups: control (C, no removals); four functional group removal treatments (PG, perennial grass removed; S, shrubs removed; SSh, subshrubs removed; Succ, succulents removed), and three species richness manipulation treatments. Richness manipulations included a simplified treatment (Simp), where only the single most abundant species of each growth form is preserved and all other species in the growth form are removed, a reduced‐Larrea treatment (rL), where the Larrea is assumed to be the dominant and is removed while minority components remain, and a reduced-Prosopsis treatment (rP), where Prosopis rather than Larrea is removed as the shrub dominant. The amount of plant material removed during the establishment of these treatments was recorded for later use as covariate or measure of disturbance. Removed fresh material was weighed in the field by species, then converted to dry mass using a subset of removed plot vegetation that was oven-dried and weighed in the lab. Variables in this file summarize the dry mass of plants removed by growth form (functional group, i.e. shrub, subshrub, perennial grass, succulent), and by total live dry mass, for each plot in the biodiversity experiment. Also provided are masses of dead material collected from plots (same groups as live material removed for each treatment) and total dry mass, live plus dead. Species-level data are available upon request. This study is complete. 

This dataset contains vegetative cover data of plots that have had various plant functional groups or species experimentally removed at the Jornada Basin LTER site in southern New Mexico, USA. This data was collected with the objective to distinguish the differential effects of plant community biomass, functional groups, and biodiversity within functional groups on ecosystem and plant community function. To make these distinctions, treatments were established by the selective removal of plant species or functional groups within experimental plots. There are eight treatments: control (C, no removals); four functional group removal treatments (PG, perennial grass removed; S, shrubs removed; SSh, subshrubs removed; Succ, succulents removed), and three species richness manipulation treatments. Richness manipulations included a simplified treatment (Simp), where only the single most abundant species of each growth form is preserved and all other species in the growth form are removed, a reduced‐Larrea treatment (rL), where the Larrea is assumed to be the dominant and is removed while minority components remain, and a reduced-Prosopsis treatment (rP), where Prosopis rather than Larrea is removed as the shrub dominant. Following treatments, vegetative data was collected by sampling each plot along three transects twice a year (Spring and Fall) for 5 years from 1997-2002 (no data collected in 1998). This data set consists of the date of collection, plot number, treatment type, transect number, quadrat number, species codes, two diameters, height, condition, count, record IDs, and error codes. This study is complete. 

This dataset contains individual species size data in vegetation plots that have had various plant functional groups or species experimentally removed at the Jornada Basin LTER site in southern New Mexico, USA. This data was collected with the objective to distinguish the differential effects of plant community biomass, functional groups, and biodiversity within functional groups on ecosystem and plant community function. To make these distinctions, treatments were established by the selective removal of plant species or functional groups within experimental plots. There are eight treatments: control (C, no removals); four functional group removal treatments (PG, perennial grass removed; S, shrubs removed; SSh, subshrubs removed; Succ, succulents removed), and three species richness manipulation treatments. Richness manipulations included a simplified treatment (Simp), where only the single most abundant species of each growth form is preserved and all other species in the growth form are removed, a reduced‐Larrea treatment (rL), where the Larrea is assumed to be the dominant and is removed while minority components remain, and a reduced-Prosopsis treatment (rP), where Prosopis rather than Larrea is removed as the shrub dominant. In 1999, this pilot study attempted to assess individual species responses of representative individuals in these treatments. Ten randomly selected individuals of eight plant species were measured in each experimental plot, and this dataset reports volumetric data (diameters and height) for each. The study was designed as an individual-based complement to the transect data in EDI dataset knb-lter-jrn.210121001 but was not continued past 1999. This dataset is complete. 

This package contains values of mean annual aboveground net primary production (NPP, in grams per square meter per year) at 15 NPP study sites on Jornada Experimental Range (JER) and Chihuahuan Desert Rangeland Research Center (CDRRC) lands. Sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. All sites are excluded from domestic grazing. Eleven sites are in non-grazed pastures, and at the other four sites 1 hectare areas around the observational plots were fenced in 1988. At all sites a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. In fall, winter, and spring periods aboveground biomass was calculated for each species and quadrat at each NPP site. These calculations rely on two data sources: 1) non-destructive horizontal cover and vertical height measurements of individual plants, or plant parts, within each quadrat, and 2) linear regression coefficients for each plant species derived from off-quadrat cover, height, and harvested biomass measurements. NPP is then calculated as the positive biomass increment between seasons. The annual totals in this dataset are derived by summing mean site NPP values for winter (October - February), spring (February - May), and fall (May - October) increments for a single calendar year. Data collection is ongoing with new annual NPP values calculated after the conclusion of each growing season. Attention: 1) Calculated values in this data package have changed over time as the methodology for estimating biomass has changed. If you are updating or adding to an earlier analysis of these data we recommend consulting with the dataset authors or a Jornada data manager. 2) Relating long-term NPP in this package with long-term precipitation is problematic given the importance of wet and dry periods and their effect on production in these ecosystems. 3) Data from 2013 and later are currently in provisional status and subject to change as we review the allometric equations used for estimating biomass. See Notes in the methods element for further details. 

This data package contains reference harvest measurements for the long-term Net Primary Production (NPP) study at the Jornada Basin LTER. Data here include horizontal cover, vertical height, and aboveground biomass of plants harvested near, but outside, a grid of permanent NPP quadrats at each of 15 NPP sites. These sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. All sites are excluded from domestic grazing. Eleven sites are in non-grazed pastures, and at the other four sites 1 hectare areas around the observational plots were fenced in 1988. At all sites a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. Harvests are made outside the quadrat grid, but inside the fence. Height and cover are recorded in the field. Live biomass is weighed in the lab and all measurements are recorded as reference harvest data. Subsequently, regressions between the harvested biomass and plant volume values are used to derive allometric equations that determine biomass from non-destructive volume measurements in the permanent NPP quadrats. Further details are described in the methods metadata. This is an ongoing study with new harvest data (from selected species) collected in the spring, fall, and winter each year. Attention: These data are not appropriate for estimates of percentage cover because of the way the data are collected. 

This data package contains aboveground vegetation cover, volume, and calculated biomass values at the 15 Net Primary Production (NPP) study sites on Jornada Experimental Range (JER) and Chihuahuan Desert Rangeland Research Center (CDRRC) lands. Sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. All sites are excluded from domestic grazing. Eleven sites are in non-grazed pastures, and at the other four sites 1 hectare areas around the observational plots were fenced in 1988. At all sites a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. For each quadrat, aboveground biomass has been calculated from two data sources: 1) non-destructive horizontal cover and vertical height measurements of individual plants, or plant parts, within each quadrat, and 2) linear regression coefficients for each plant species derived from off-quadrat cover, height, and harvested biomass measurements. Non-destructive measurements (1) are taken during winter, spring, and fall measurement campaigns, then aggregated by species for each quadrat, and resulting dimensions are used to calculate species biomass (grams) by quadrat and season using using the species-specific regression coefficients derived from dataset 2. This is the most detailed biomass dataset available and can be used to derive values of net primary production between seasons or annually. Each dataset record contains calculated biomass (and related variables) by species, quadrat, season, and site. Data collection is ongoing with new observations in spring, fall, and winter of each year, but this data package may be updated less frequently. Attention: 1) For most species, these data are not appropriate for estimates of percentage cover or volume because of the way the data are collected. 2) Calculated values in this data package have changed over time as the methodology for estimating biomass has changed. If you are updating or adding to an earlier analysis of these data we recommend consulting with the dataset authors or a Jornada data manager. 3) Relating long-term NPP derived from this package with long-term precipitation is problematic given the importance of wet and dry periods and their effect on production in these ecosystems. 4) Data from 2013 and later are currently in provisional status and subject to change as we review the allometric equations used for estimating biomass. See Notes in the methods element for further details. 

This data package contains non-destructive quadrat measurements collected for the long-term Net Primary Production (NPP) study at the Jornada Basin LTER. Data here include measurements of horizontal cover and vertical height of plants observed at permanent NPP quadrats at 15 study sites. Sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. All sites are excluded from domestic grazing. Eleven sites are in non-grazed pastures, and at the other four sites 1 hectare areas around the observational plots were fenced in 1988. At all sites a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. Grids consist of 49 quadrats arranged in a square 7 x 7 pattern, with quadrats 10 m apart (P-COLL has 48 quadrats in a 3 x 16 pattern). Standing vegetation in quadrats is sampled three times a year: in winter (February - March), before shrubs begin spring growth; in spring (May), when shrubs and spring annuals have reached peak biomass; in fall (late summer; October), when summer annuals have reached peak biomass but before killing frosts. Additional observations of plant count and phenological stage are also made. This dataset is subsequently used to determine quadrat biomass and net primary production. Details and linked data packages are described in the methods element. This is an ongoing dataset with new quadrat measurements collected in the spring, fall and winter of each year. Attention: 1) For most species, these data are not appropriate for estimates of percentage cover because of the way the data are collected. See Note 1 in the methods element for further details. 

This dataset contains long-term precipitation measurements from graduated rain gauges (GRGs) at 21 sites in the Jornada Basin of southern New Mexico, USA. Gauges are located on the Jornada Experimental Range (JER) and the Chihuahuan Desert Rangeland Research Center (CDRRC), and this set of gauges includes all 15 net primary production (NPP) study sites monitored by the Jornada Basin LTER program. At each site a 4 inch diameter cylindrical graduated rain gauge (11" x 0.01" capacity) is mounted on a 4x4 inch diameter redwood post or a wooden exclosure post next to gate at or near each site. For NPP sites, the primary collection is made on the day that monthly hydroprobe soil water content measurements are made. This enables correlation of precipitation with belowground soil water content. Additional data collections during the month may be made in coordination with other studies. Observations at each site come primarily from GRGs. However, at some sites in the NPP study, GRGs were not installed until later, and the nearest available rain gauge in the area has been used to gapfill the precipitation record prior to installation (details in methods section). Rain gauge identity and field measurement date is recorded with each observation in the data file. Other gauge types that may be listed are the Standard Can Gauge (DSRG or dipstick rain gauge), Belfort Weigh Bucket Rain Gauge (WBRG), and Qualimetrics Tipping Bucket Rain Gauge (TBRG). Data collection is ongoing for all 21 gauges in this dataset. 

This data package contains aboveground vegetation cover, volume, and calculated biomass values at the 15 Net Primary Production (NPP) study sites on Jornada Experimental Range (JER) and Chihuahuan Desert Rangeland Research Center (CDRRC) lands. Sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. At each site, a 1 hectare area was fenced in 1988 and a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. For each quadrat, aboveground biomass has been calculated from two data sources: 1) non-destructive horizontal cover and vertical height measurements of individual plants, or plant parts, within each quadrat, and 2) linear regression coefficients for each plant species derived from off-quadrat cover, height, and harvested biomass measurements. Non-destructive measurements (1) are taken during winter, spring, and fall measurement campaigns, then aggregated by species for each quadrat, and resulting dimensions are used to calculate species biomass (grams) by quadrat and season using using the species-specific regression coefficients derived from dataset 2. This is the most detailed biomass dataset available and can be used to derive values of net primary production between seasons or annually. Each dataset record contains calculated biomass (and related variables) by species, quadrat, season, and site. Data collection is ongoing with new observations in spring, fall, and winter of each year, but this data package may be updated less frequently. Attention: 1) For most species, these data are not appropriate for estimates of percentage cover because of the way the data are collected. 2) Calculated values in this data package have changed over time as the methodology for estimating biomass has changed. 3) Relating long-term NPP derived from this package with long-term precipitation is problematic given the importance of wet and dry periods and their effect on production in these ecosystems. 4) Data from 2013 and later are currently in provisional status and subject to change as we review the allometric equations used for estimating biomass. See Notes in the methods element for further details. 

This package contains values of mean annual aboveground net primary production (NPP, in grams per square meter per year) at 15 NPP study sites on Jornada Experimental Range (JER) and Chihuahuan Desert Rangeland Research Center (CDRRC) lands. Sites were selected to represent the 5 major ecosystem types in the Chihuahuan Desert (upland grasslands, playa grasslands, mesquite-dominated shrublands, creosotebush-dominated shrublands, tarbush-dominated shrublands). For each ecosystem type, three sites were selected to represent the range in variability in production and plant diversity; thus the locations are not replicates. At each site, a 1 hectare area was fenced in 1988 and a grid of 49 (48 at one playa location) 1m x 1m replicate quadrats was laid out when sampling began in 1989. In fall, winter, and spring periods aboveground biomass was calculated for each species and quadrat at each NPP site. These calculations rely on two data sources: 1) non-destructive horizontal cover and vertical height measurements of individual plants, or plant parts, within each quadrat, and 2) linear regression coefficients for each plant species derived from off-quadrat cover, height, and harvested biomass measurements. NPP is then calculated as the positive biomass increment between seasons. The annual totals in this dataset are derived by summing mean site NPP values for winter (October - February), spring (February - May), and fall (May - October) increments for a single calendar year. Data collection is ongoing with new annual NPP values calculated after the conclusion of each growing season. Attention: 1) Calculated values in this data package have changed over time as the methodology for estimating biomass has changed. 2) Relating long-term NPP in this package with long-term precipitation is problematic given the importance of wet and dry periods and their effect on production in these ecosystems. 3) Data from 2013 and later are currently in provisional status and subject to change as we review the allometric equations used for estimating biomass. See Notes in the methods element for further details.