plant cover

East and west boundary fence plant line intercepts - percent cover for all species beginning 1986

Study number: 

120

Data set ID: 

210120001

Date range: 

1986-09-24 to 2005-10-29

Original investigator: 

Walter G Whitford

Data contact: 

Abstract: 

BACKGROUND. In the spring of 1982, as part of the establishment of the Jornada Long-Term Ecological Research site in southern New Mexico, a 135 ha portion of a 1500 ha, internally drained, watershed was exclosed from grazing by domestic livestock. Prior to exclosure the watershed, as well as the rest of the Jornada basin, had been moderately to heavily grazed for the past 100 years.

Concurrent with grazing, the vegetation had undergone a dramatic change from desert grassland, with an almost continuous cover of C4 perennial grasses, to isolated patches of the original grassland in a mosaic with desert shrub dominated plant communities (Buffington and Herbel, 1965). The exclosure lies along a northeast facing piedmont slope at the base of a steep isolated mountain peak, and covers a variety of component landforms from the foot of the mountain to the basin floor. This provided the opportunity to investigate the response of vegetation with respect to landscape characteristics as well as release from grazing. This summary data set consists of percent cover of all perennial plant species from the plant line intercept measurements on either side of the LTER-I exclosure East and West boundary fence. Data is sorted by treatment (grazed, ungrazed), year, fence line, station, then species i.d. Along the East Boundary fence line, the east side is ungrazed (control) and the west side is grazed (treatment). Along the West Boundary fence line, the east side is grazed and the west side is ungrazed. Each plant line transect is divided into 6 5-meter segments. All perennials were measured at about 5 year intervals as the length of intercept for each species along a 30-meter line oriented perpendicular to the fence. Summary data presented in this data set is the average percent cover for the outer-most 2 5-meter segments for the respective treatment (grazed or ungrazed). The term outer-most is relative to the fence. The 5-meter segment on either side of the fence is not included in the cover estimates due to fence line effect disturbances; e.g., cattle trails, tumbleweeds trapped along fence, etc. This summary data does not include the first year of measurement in 1982 because of numerous problems with species codes used that could not resolved.

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East and west boundary fence plant line intercepts - percent cover for 9 species, Jornada Basin, 1982 to 1992

Study number: 

120

Data set ID: 

210120002

Date range: 

1982-10-08 to 1992-09-11

Original investigator: 

Walter G Whitford

Data contact: 

Abstract: 

BACKGROUND. In the spring of 1982, as part of the establishment of the Jornada Long-Term Ecological Research site in southern New Mexico, a 135 ha portion of a 1500 ha, internally drained, watershed was exclosed from grazing by domestic livestock. Prior to exclosure the watershed, as well as the rest of the Jornada basin, had been moderately to heavily grazed for the past 100 years.

Concurrent with grazing, the vegetation had undergone a dramatic change from desert grassland, with an almost continuous cover of C4 perennial grasses, to isolated patches of the original grassland in a mosaic with desert shrub dominated plant communities (Buffington and Herbel, 1965). The exclosure lies along a northeast facing piedmont slope at the base of a steep isolated mountain peak, and covers a variety of component landforms from the foot of the mountain to the basin floor. This provided the opportunity to investigate the response of vegetation with respect to landscape characteristics as well as release from grazing. This summary data set consists of percent cover of 9 species from the plant line intercept measurements on either side of the LTER-I exclosure East and West boundary fence. Data is sorted by station, species i.d., then line segment. Along the East Boundary fence, the east side is ungrazed (control) and the west side is grazed (treatment). Along the West Boundary fence, the east side is grazed and the west side is ungrazed. Each plant line transect is divided into 6 5-meter segments. All perennials were measured at about 5 year intervals as the length of intercept along a 30-meter line perpendicular to the fence. Summary data includes only four of the 6 5-meter intervals due to disturbance along fenceline. Data from the 5-meter segment on either side of the fence was not included in summarizing the data. Summary data includes only 9 of the perennial species.

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Plant cover in precipitation and nitrogen treatment plots (by species)

Study number: 

27

Data set ID: 

2100278002

Date range: 

2006-10-01 to 2008-09-30

Original investigator: 

Lara G Reichmann

Data contact: 

Abstract: 

We use vegetation cover as a proxy for plant biomass to avoid confounding spatial and temporal variability or confounding the impact of harvesting. The rate of biomass change is Aboveground net primary production, a key variable that will respond to our PPT and nutrient manipulations.

Measured variables: individual cover of plant species measured as cm of green biomass that intercepts a 250cm long line, then averaged for 3 lines/plot.

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Arson burn on LTER-I Transect plant line intercepts - field data (tape format)

Study number: 

384

Data set ID: 

210384001

Original investigator: 

John Anderson

Abstract: 

LTER-I Transect plant line intercept data. This data set is as transcribed (UNSORTED) from cassette tape with one intercept observation per record. Data consist of week number, transect, station, segment number, plant species, and length of species intercepted by line stretched between 2 rebar the length of the 30 meter plant line intercept transect.

Measurements are made on 30-meter line intercept transects located perpendicular to each of 91 stations on each of the 2.7 km long Control, Treatment, and Alternate Control Transects established at the beginning of LTER-I. Each plant line transect is divided into 6 5-meter segments. Annuals are measured only in the first meter of segments 1, 2, and 3 and in the last meter of segments 4, 5, and 6. Perennials are measured for the full length of all segments. On March 19, 2000, an arson burn occurred of 2.5 acres of the upper grassland area on the Summerford bajada just below the powerline road. The area affected included portions of the LTER-I Transect Plant Line Intercept study that was begun in 1982. To evaluate the impact of the burn on those lines, the line intercepts were read for the upper grassland area extending from immediately above the creosotebush fringe to the base of Summerford Mountain. The stations measured were C73-C89, T75-T90, and X76-X91 (Control, Treatment, and Alternate Control, respectively). Measurements were made immediately after the burn, after the spring growing season, and after the fall growing season in 2000 only. In the initial sampling period, the burn area intercepted by the line was noted in the data set using a "species" code of BURN. BACKGROUND. In the spring of 1982, as part of the establishment of the Jornada Long-Term Ecological Research site in southern New Mexico, a 135 ha portion of a 1500 ha, internally drained, watershed was exclosed from grazing by domestic livestock. Prior to exclosure the watershed, as well as the rest of the Jornada basin, had been moderately to heavily grazed for the past 100 years. Concurrent with grazing, the vegetation had undergone a dramatic change from desert grassland, with an almost continuous cover of C4 perennial grasses, to isolated patches of the original grassland in a mosaic with desert shrub dominated plant communities (Buffington and Herbel, 1965). The exclosure lies along a northeast facing piedmont slope at the base of a steep isolated mountain peak, and covers a variety of component landforms from the foot of the mountain to the basin floor. This provided the opportunity to investigate the response of vegetation with respect to landscape characteristics as well as release from grazing.

Arson burn on LTER-I transect plant line intercepts - LT series (percent cover)

Study number: 

384

Data set ID: 

210384002

Original investigator: 

John Anderson

Abstract: 

On March 19, 2000, an arson burn occurred of 2.5 acres of the upper grassland area on the Summerford bajada just below the powerline road. The area affected included portions of the LTER-I Transect Plant Line Intercept study that was begun in 1982.

To evaluate the impact of the burn on those lines, the line intercepts were read for the upper grassland area extending from immediately above the creosotebush fringe to the base of Summerford Mountain. The stations measured were C73-C89, T75-T90, and X76-X91 (Control, Treatment, and Alternate Control, respectively). Measurements were made immediately after the burn, after the spring growing season, and after the fall growing season in 2000 only. In the initial sampling period, the burn area intercepted by the line was noted in the data set using a "species" code of BURN. Average percent coverage of each plant species per 5-meter segment along a 30-meter line intercept perpendicular to each of 91 stations on each of the three LTER-I permanent transects. Data consists of week number, transect, station number, species, carbon reduction pathway, habit, form, and average percent cover. It is sorted by transect, station number, then plant species. Measurements are made on 30-meter line intercept transects located perpendicular to each of 91 stations on each of the 2.7 km long Control, Treatment, and Alternate Control Transects established at the beginning of LTER-I. Following January 1, 1987, spring line- intercepts will only record cover of annual species. All perennial cover data will be limited to fall samples. Both annuals and perennials are measured during the fall. Measurements were made biannually from 1982 - 1988. After this they are measured every 5 years. Annuals are measured through 1998; however, after this only perennials are measured and only in the fall. Each plant line transect is divided into 6 5-meter segments. Annuals are measured only in the first meter of segments 1, 2, and 3 and in the last meter of segments 4, 5, and 6. Perennials are measured for the full length of all segments. BACKGROUND. In the spring of 1982, as part of the establishment of the Jornada Long-Term Ecological Research site in southern New Mexico, a 135 ha portion of a 1500 ha, internally drained, watershed was exclosed from grazing by domestic livestock. Prior to exclosure the watershed, as well as the rest of the Jornada basin, had been moderately to heavily grazed for the past 100 years. Concurrent with grazing, the vegetation had undergone a dramatic change from desert grassland, with an almost continuous cover of C4 perennial grasses, to isolated patches of the original grassland in a mosaic with desert shrub dominated plant communities (Buffington and Herbel, 1965). The exclosure lies along a northeast facing piedmont slope at the base of a steep isolated mountain peak, and covers a variety of component landforms from the foot of the mountain to the basin floor. This provided the opportunity to investigate the response of vegetation with respect to landscape characteristics as well as release from grazing.

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Transect plant line intercepts - percent cover by species

Study number: 

119

Data set ID: 

2100119001

Date range: 

1982-03-12 to 2003-11-19

Original investigator: 

Gary Cunningham

Data contact: 

Abstract: 

Average percent coverage of each plant species per 5-meter segment along a 30-meter line intercept perpendicular to each of 91 stations on each of the three LTER-I permanent transects. Data consists of week number, transect, station number, species, carbon reduction pathway, habit, form, and average percent cover. It is sorted by transect, station number, then plant species.

Measurements are made on 30-meter line intercept transects located perpendicular to each of 91 stations on each of the 2.7 km long Control, Treatment, and Alternate Control Transects established at the beginning of LTER-I. Following January 1, 1987, spring line- intercepts will only record cover of annual species. All perennial cover data will be limited to fall samples. Both annuals and perennials are measured during the fall. Measurements were made biannually from 1982 - 1988. After this they are measured every 5 years. Annuals are measured through 1998; however, after this only perennials are measured and only in the fall. Each plant line transect is divided into 6 5-meter segments. Annuals are measured only in the first meter of segments 1, 2, and 3 and in the last meter of segments 4, 5, and 6. Perennials are measured for the full length of all segments. BACKGROUND. In the spring of 1982, as part of the establishment of the Jornada Long-Term Ecological Research site in southern New Mexico, a 135 ha portion of a 1500 ha, internally drained, watershed was exclosed from grazing by domestic livestock. Prior to exclosure the watershed, as well as the rest of the Jornada basin, had been moderately to heavily grazed for the past 100 years. Concurrent with grazing, the vegetation had undergone a dramatic change from desert grassland, with an almost continuous cover of C4 perennial grasses, to isolated patches of the original grassland in a mosaic with desert shrub dominated plant communities (Buffington and Herbel, 1965). The exclosure lies along a northeast facing piedmont slope at the base of a steep isolated mountain peak, and covers a variety of component landforms from the foot of the mountain to the basin floor. This provided the opportunity to investigate the response of vegetation with respect to landscape characteristics as well as release from grazing.

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Hydrology natural runoff plots plant cover

Study number: 

1

Data set ID: 

210001001

Date range: 

1982-09-09 to 1994-10-15

Original investigator: 

Tim Ward

Data contact: 

Abstract: 

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.

Density and cover of winter annual plants

Study number: 

368

Data set ID: 

210368001

Original investigator: 

Rodolfo R Di Marco

Data contact: 

Abstract: 

The purpose of this investigation was to answer three general questions: 1. How does the modification of soil properties and the ratios of resources (e.g., water-N) by ants alter species assemblages of winter annual plants at the edge of the ant nests? 2.

How does the "spring cleaning", clipping, predation or herbivory by ants affect success of the winter annual plants at the edge of ant nests? 3. Are there significant differences in the floristic assemblage and belowground standing crop (root biomass) between the edge of ant nest and the surrounding unaffected soils? Data set contains density and cover of all winter annual plants measured at regular intervals. Density is expressed as the number of individuals of a species per square meter. The cover of each species was calculated as the area covered by a perpendicular (not vertical) projection of its aerial parts onto the ground surface and expressed in covered area (cm squared) per square meter.

Data download: 

Erosion zone vegetation

Study number: 

121

Data set ID: 

2100121002

Original investigator: 

John Anderson

Abstract: 

Overview:
In semiarid ecosystems the diversity of plant functional types (
grasses, shrubs, succulents, and so on) and of species may interact
with the severe stresses imposed by the desert environment to influence
ecosystem processes. Erosion and transport of surface sediment by wind

Overview:
In semiarid ecosystems the diversity of plant functional types (
grasses, shrubs, succulents, and so on) and of species may interact
with the severe stresses imposed by the desert environment to influence
ecosystem processes. Erosion and transport of surface sediment by wind
and water is one process that may be affected by the physical structure
of the plant community. The Jornada plant diversity experiment, in
which the diversity and structure of the plant community have been
manipulated in large (25 m x 25 m) plots, offers the opportunity to
examine the relative importance of vegetation characteristics and
landscape position in determining rates of sediment movement within
the plots.
Each of the 48 plots of the plant diversity experiment contains
5 pans or trays on the downslope side; these accumulate sediments and
plant litter that are moving within the plots (carried by wind or by
water). Data have been collected on the amount of sediment accumulated
in the pans during rainy and during dry seasons, with material sorted
and weighed as fine ( 2 mm) mineral sediment,
plant litter, or rabbit/jackrabbit pellets. Previous statistical analyses
found that the mass of material collected per plot is explained only poorly
by the treatment (plant community manipulation) of the plot and by block
(a rough indication of location on the slope).

Objectives:
We will test the relative significance of the following variables
in explaining plot-level accumulations of sediment and litter: treatment,
block, position on slope (the row, from 1 (top of slope) to 10 (bottom),
in which the plot is located), the treatment of the plot immediately upslope
from the plot, and indices of plant cover and volume (total and by
functional group) from the plot-level sampling of vegetation (using
fall 1997 data).
In addition, we will test the significance of the following variables
in explaining the accumulation of sediment and litter in individual pans
within a plot: all variables listed above for the plot, plus indices of
the vegetative cover and volume located immediately upslope of the pan
(weighted for distance from the pan itself).

Response variables:
Vegetative cover measurements are made immediately upslope of
erosion pans to estimate plant cover and volume. This is done at
two scales. The three large quadrats (2 m x 2 m) are used to look
at all large plants (height > 25 cm) rooted within them. The six
small plots (50 cm x 50 cm) are used to look at all small plants
(greater or equal to 3 cm maximum diameter, but less than or equal
to 10 cm) rooted within them. Maximum diameter, maximum perpendicular
diameter, and height are measured to the nearest centimeter.

Data download: 

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