{"Abstract":["The U.S. Fish and Wildlife's plan to apply a prescribed burn to a\n large portion of McKenzie Flats was deemed an opportunity to study\n the effects of fire on vegetation at the boundary between shrubland\n and grassland. This study actually was undertaken on an area that\n had prescribed fire applied to 8 of 16 (300 m x 300 m) plots 10\n years before in 1993. This previous study had also examined the\n effects of fencing to exclude the indigenous prong-horn antelope. In\n the 2003 study the prescribed fire was applied to the northeastern\n half of the 16 plots while the southwestern plots were intentionally\n protected. Sampling prior to the prescribed burn included\n quantification of cover of grass species in quadrats within all of\n the 16 plots. Measurements were made using "niner" quadrat\n frames that are 30 cm x 30 cm frames that are divided into 9\n 1-decimeter squares. Counts of grass species were made just prior to\n the June 2003 burn. Following the prescribed burn, quadrats were\n remeasured in the fall of 2003 to quantify mortality of grass\n species. These measurements were taken through the fall of 2012 and\n the fall of 2018. Measurements were not taken for 2014-2017."]}
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2003 Prescribed Burn Effect on Chihuahuan Desert Grasses and Shrubs at the Sevilleta National Wildlife Refuge, New Mexico: Grass Recovery Study (2003-2018)
The U.S. Fish and Wildlife's plan to apply a prescribed burn to a large portion of McKenzie Flats was deemed an opportunity to study the effects of fire on the vegetation at the boundary between shrubland and grassland. This study actually was undertaken on an area that had prescribed fire applied to 8 of 16 (300 m x 300 m) plots 10 years before in 1993. This previous study had also examined the effects of fencing to exclude the indigenous prong-horn antelope. In the 2003 study the prescribed fire was applied to the northeastern half of the 16 plots while the southwestern plots were intentionally protected. Sampling prior to the prescribed burn included quantification of fuel load (ie. the standing biomass of all grasses and forbs in the area to be burned). These measurements were made using Daubenmire quadrat frames that are 5 cm x 20 cm and delineate a 0.1 square meter area. Four samples were taken adjacent to the six 3 m x 4 m quadrats in each of the eight plots that were to be burned. Quadrat frames were laid down over the vegetation and all vegetation rooted within the frame was clipped at ground level. This material was bagged, oven-dried and weighed. Following the prescribed burn, re-measurements were made every fall of from 2004 until 2012 when vegetation had reached its annual peak biomass. Data were not collected from 2014-2017, but were collected again in 2018.
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- Award ID(s):
- 1655499
- PAR ID:
- 10424127
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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{"Abstract":["In 2003, the U.S. Fish and Wildlife Service conducted a prescribed\n burn over a large part of the northeastern corner of the Sevilleta\n National Wildlife Refuge. Following this burn, a study was designed\n to look at the effect of fire on above-ground net primary\n productivity (ANPP) (i.e., the change in plant biomass, represented\n by stems, flowers, fruit and foliage, over time) within three\n different vegetation types: mixed grass (MG), mixed shrub (MS) and\n black grama (G). Forty permanent 1m x 1m plots were installed in\n both burned and unburned (i.e., control) sections of each habitat\n type. The core black grama site included in SEV129 is used as a G\n control site for analyses and does not appear in this dataset. The\n MG control site caught fire unexpectedly in the fall of 2009 and\n some plots were subsequently moved to the south. For details of how\n the fire affected plot placement, see Methods below. In spring 2010,\n sampling of plots 16-25 was discontinued at the MG (burned and\n control) and G (burned treatment only) sites, reducing the number of\n sampled plots to 30 at each.To measure ANPP (i.e., the change in\n plant biomass, represented by stems, flowers, fruit and foliage,\n over time), the vegetation variables in this dataset, including\n species composition and the cover and height of individuals, are\n sampled twice yearly (spring and fall) at each plot. The data from\n these plots is used to build regressions correlating biomass and\n volume via weights of select harvested species obtained in SEV157,\n "Net Primary Productivity (NPP) Weight Data." This biomass\n data is included in SEV185, "Burn Study Sites Seasonal Biomass\n and Seasonal and Annual NPP Data.""]}more » « less
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{"Abstract":["In 2003, the U.S. Fish and Wildlife Service conducted a prescribed\n burn over a large part of the northeastern corner of the Sevilleta\n NWR. This study was designed to look at the effect of fire on\n above-ground net primary productivity (ANPP) within different\n vegetation types. Net primary production (NPP) is a fundamental\n ecological variable that measures rates of carbon consumption and\n fixation. Estimates of NPP are important in understanding energy\n flow at a community level as well as spatial and temporal responses\n to a range of ecological processes. While measures of both below-\n and above-ground biomass are important in estimating total NPP, this\n study focuses on above-ground net primary production (ANPP).\n Above-ground net primary production (ANPP) is equal to the change in\n plant mass, including loss to death and decomposition, over a given\n period of time. To measure this change, ANPP is sampled twice a year\n (spring and fall) for all species in each of three vegetation types.\n In addition, volumetric measurements are obtained from adjacent\n areas to build regressions correlating biomass and volume. Three\n vegetation types were chosen for this study: mixed grass (MG), mixed\n shrub (MS) and black grama (G). Forty permanent 1m x 1m plots were\n installed in both burned and unburned sections of each habitat type.\n The core black grama site included in SEV129 was incorporated into\n this dataset as an unburned control, so an additional unburned G\n site was not created. The data for this site is noted as site=G and\n treatment=C (i.e., control). The original mixed-grass unburned plot\n caught fire unexpectedly in the fall of 2009 and was subsequently\n moved to the south. Volumetric measurements are made using\n vegetation data from permanent plots collected in SEV156, "Burn\n Study Sites Quadrat Data for the Net Primary Production Study"\n and regressions correlating biomass and volume constructed using\n seasonal harvest weights from SEV157, "Net Primary Productivity\n (NPP) Weight Data.""]}more » « less
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