Understanding how global change drivers (GCDs) affect aboveground net primary production (ANPP) through time is essential to predicting the reliability and maintenance of ecosystem function and services in the future. While GCDs, such as drought, warming and elevated nutrients, are known to affect mean ANPP, less is known about how they affect inter-annual variability in ANPP. We examined 27 global change experiments located in 11 different herbaceous ecosystems that varied in both abiotic and biotic conditions, to investigate changes in the mean and temporal variability of ANPP (measured as the coefficient of variation) in response to different GCD manipulations, including resource additions, warming, and irrigation. From this comprehensive data synthesis, we found that GCD treatments increased mean ANPP. However, GCD manipulations both increased and decreased temporal variability of ANPP (24% of comparisons), with no net effect overall. These inconsistent effects on temporal variation in ANPP can, in part, be attributed to site characteristics, such as mean annual precipitation and temperature as well as plant community evenness. For example, decreases in temporal variability in ANPP with the GCD treatments occurred in wetter and warmer sites with lower plant community evenness. Further, the addition of several nutrients simultaneously increased the sensitivity of ANPP to interannual variation in precipitation. Based on this analysis, we expect that GCDs will likely affect the magnitude more than the reliability over time of ecosystem production in the future.
Bibliographical noteFunding Information:
We are grateful to the LTER Network for funding synthesis working groups in 2012 and 2016 for this work NSF EF 1545288, NSF EF 0553768. We are very thankful for the researchers who provided data for this manuscript and the technical staff at these sites who both answered our questions and assured that the long-term integrity of these data are/were maintained. Not all of the researchers who contributed data to this project are listed as authors, so we specifically want to acknowledge their contributions: John Blair and Elizabeth H. Boughton. All authors report no conflict of interest. Funding sources for individual experiments included in the data synthesis can be found in Table S2.
Order of authorship was determined by contribution and then alphabetically. MLA, KRW, KJK, NL, WDB, SLC, AK, SEK, MDS conceived of the analyses. MLA performed the analyses in consultation with KRW, KJK and NL. MLA, WDB, SLC, AK, MDS, SGB, KLG, FI, JML, PBR, KNS, KBS, DT, ZX, and QY contributed data. QY was supported by the National Key R&D Program of China (2017YFA0604802). MLA wrote the manuscript, and all authors provided input on the analyses and edited the manuscript.
- Ecosystem function
- Primary production
PubMed: MeSH publication types
- Journal Article