The objective of this ongoing study is to investigate how pulses of
precipitation translate into pulses of plant aboveground net primary
productivity (NPP) across grassland to shrubland ecotones in the
northern Chihuahuan Desert. This dataset consists of annual
aboveground net primary productivity estimates in three habitat
vegetation zones (grassland, ecotone, and shrubland) at three
grassland-to-shrubland ecotone sites in the Jornada Basin, Dona Ana
County, New Mexico, USA. The annual ANPP estimates are derived from
plant cover measurements (see methods). Due to its growth form,
Yucca elata (YUEL) has been found to produce large errors in
interyear biomass estimates. This data package contains annual ANPP
estimates both with and without YUEL, but the authors strongly
recommend using the non-YUEL estimates for most purposes. Data
collection is ongoing with new observations in spring and fall of
each year; data from both annual sampling times are required to
estimate annual ANPP.
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As above, not so below: Long‐term dynamics of net primary production across a dryland transition zone
Drylands are key contributors to interannual variation in the terrestrial carbon sink, which has been attributed primarily to broad‐scale climatic anomalies that disproportionately affect net primary production (NPP) in these ecosystems. Current knowledge around the patterns and controls of NPP is based largely on measurements of aboveground net primary production (ANPP), particularly in the context of altered precipitation regimes. Limited evidence suggests belowground net primary production (BNPP), a major input to the terrestrial carbon pool, may respond differently than ANPP to precipitation, as well as other drivers of environmental change, such as nitrogen deposition and fire. Yet long‐term measurements of BNPP are rare, contributing to uncertainty in carbon cycle assessments. Here, we used 16 years of annual NPP measurements to investigate responses of ANPP and BNPP to several environmental change drivers across a grassland–shrubland transition zone in the northern Chihuahuan Desert. ANPP was positively correlated with annual precipitation across this landscape; however, this relationship was weaker within sites. BNPP, on the other hand, was weakly correlated with precipitation only in Chihuahuan Desert shrubland. Although NPP generally exhibited similar trends among sites, temporal correlations between ANPP and BNPP within sites were weak. We found chronic nitrogen enrichment stimulated ANPP, whereas a one‐time prescribed burn reduced ANPP for nearly a decade. Surprisingly, BNPP was largely unaffected by these factors. Together, our results suggest that BNPP is driven by a different set of controls than ANPP. Furthermore, our findings imply belowground production cannot be inferred from aboveground measurements in dryland ecosystems. Improving understanding around the patterns and controls of dryland NPP at interannual to decadal scales is fundamentally important because of their measurable impact on the global carbon cycle. This study underscores the need for more long‐term measurements of BNPP to improve assessments of the terrestrial carbon sink, particularly in the context of ongoing environmental change.
more » « less- PAR ID:
- 10419764
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 29
- Issue:
- 14
- ISSN:
- 1354-1013
- Page Range / eLocation ID:
- p. 3941-3953
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The objective of this ongoing study is to investigate how pulses of precipitation translate into pulses of plant aboveground net primary productivity (NPP) across grassland to shrubland ecotones in the northern Chihuahuan Desert. This dataset consists of annual aboveground net primary productivity estimates by plant functional groups in three habitat vegetation zones (grassland, ecotone, and shrubland) at three grassland-to-shrubland ecotone sites in the Jornada Basin, Dona Ana County, New Mexico, USA. The annual ANPP estimates are derived from plant cover measurements (see methods). Due to its growth form, Yucca elata (YUEL), in the leaf succulent functional group, has been found to produce large errors in interyear biomass estimates. This data package separates biomass estimates for YUEL and non-YUEL leaf succulents so that users can decide whether to combine them or keep them separate. In general, the authors recommend against using the YUEL estimates for most purposes. Data collection is ongoing with new observations in spring and fall of each year; data from both annual sampling times are required to estimate annual ANPP.more » « less
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