This three-year study at the Sevilleta LTER was designed to monitor net primary production (NPP) across two distinct ecosystems: pinon/juniper woodland (P) and juniper savannah woodland (J). Net primary production (NPP) is a fundamental ecological variable that measures rates of carbon consumption and fixation. Estimates of NPP are important in understanding energy flow at a community level as well as spatial and temporal responses of the community to a wide range of ecological processes. While measures of both below- and above-ground biomass are important in estimating NPP, this study focused on estimating above-ground biomass production (ANPP).To measure ANPP (i.e., the change in plant biomass, represented by stems, flowers, fruit and foliage, over time), the vegetation variables in this dataset, including species composition and the cover and height of individuals, were sampled twice yearly (spring and fall) at permanent 1m x 1m plots. The data from these plots was used to build regressions correlating biomass and volume via weights of select harvested species obtained in SEV157, "Net Primary Productivity (NPP) Weight Data." In addition, volumetric measurements were obtained from permanent plots to build regressions correlating biomass and volume.Spring measurements were taken in April or May when shrubs and spring annuals reached peak biomass. Fall measurements were taken in either September or October when summer annuals reached peak biomass but prior to killing frosts. Winter measurements were taken in February before the onset of spring growth.
Knowledge Network for Biocomplexity (KNB) Identifier
Data Policies: 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 provided. A copy of any publications using these data must be supplied to the Sevilleta LTER Information Manager. By downloading any data you implicitly acknowledge the LTER Data Policy (http://www.lternet.edu/data/netpolicy.html).
1999-02-01 - 2001-10-01
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).
Muldavin, Esteban (2010): Pinon Juniper Net Primary Production Quadrat Data from the Sevilleta National Wildlife Refuge, New Mexico: 1999-2001. Long Term Ecological Research Network. http://dx.doi.org/10.6073/pasta/10215d4c35430504f4d83ab724d219b5