Limits...
Drought dominates the interannual variability in global terrestrial net primary production by controlling semi-arid ecosystems.

Huang L, He B, Chen A, Wang H, Liu J, Lű A, Chen Z - Sci Rep (2016)

Bottom Line: Drought-dominated NPP, which mainly occurs in semi-arid ecosystems, explains 29% of the interannual variation in global NPP, despite its 16% contribution to total global NPP.More surprisingly, drought prone ecosystems in the Southern Hemisphere, which only account for 7% of the total global NPP, contribute to 33% of the interannual variation in global NPP.Our observations support the leading role of semi-arid ecosystems in interannual variability in global NPP and highlight the great impacts of long-term drought on the global carbon cycle.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China.

ABSTRACT
Drought is a main driver of interannual variation in global terrestrial net primary production. However, how and to what extent drought impacts global NPP variability is unclear. Based on the multi-timescale drought index SPEI and a satellite-based annual global terrestrial NPP dataset, we observed a robust relationship between drought and NPP in both hemispheres. In the Northern Hemisphere, the annual NPP trend is driven by 19-month drought variation, whereas that in the Southern Hemisphere is driven by 16-month drought variation. Drought-dominated NPP, which mainly occurs in semi-arid ecosystems, explains 29% of the interannual variation in global NPP, despite its 16% contribution to total global NPP. More surprisingly, drought prone ecosystems in the Southern Hemisphere, which only account for 7% of the total global NPP, contribute to 33% of the interannual variation in global NPP. Our observations support the leading role of semi-arid ecosystems in interannual variability in global NPP and highlight the great impacts of long-term drought on the global carbon cycle.

No MeSH data available.


Local NPP contributions to global NPP interannual variation (%).Method for calculating contributions of regional IAV to global IAV was developed by Ahlström12. Blue and red areas indicate positive and negative contributions, respectively. This map was created using the ArcGIS 10.2 (http://www.esri.com/software/arcgis/arcgis-for-desktop).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4835775&req=5

f3: Local NPP contributions to global NPP interannual variation (%).Method for calculating contributions of regional IAV to global IAV was developed by Ahlström12. Blue and red areas indicate positive and negative contributions, respectively. This map was created using the ArcGIS 10.2 (http://www.esri.com/software/arcgis/arcgis-for-desktop).

Mentions: To quantify the specific contribution of drought-controlled ecosystems to IAV, we employed the index proposed by Ahlström et al.12 to score the contribution of individual regions to IAV in global NPP. Drought-controlled ecosystems were determined as those exhibiting significant SPEI–NPP relationships (P < 0.01). These regions accounted for 29% of global NPP IAV during the study period, although their contribution to the total global NPP during this time (65.7 Pg C year−1) was only 16%. Moreover, drought-controlled ecosystems in the SH accounted for 33% of the global NPP IAV, whereas their total NPP only accounted for 7% of the total global NPP. These results provide further evidence that drought dominates the IAV in global NPP by controlling semi-arid ecosystems, especially in the SH (Fig. 3). Among the investigated biomes, evergreen broadleaf forests contributed to the largest proportion of global NPP IAV, followed by savannas.


Drought dominates the interannual variability in global terrestrial net primary production by controlling semi-arid ecosystems.

Huang L, He B, Chen A, Wang H, Liu J, Lű A, Chen Z - Sci Rep (2016)

Local NPP contributions to global NPP interannual variation (%).Method for calculating contributions of regional IAV to global IAV was developed by Ahlström12. Blue and red areas indicate positive and negative contributions, respectively. This map was created using the ArcGIS 10.2 (http://www.esri.com/software/arcgis/arcgis-for-desktop).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835775&req=5

f3: Local NPP contributions to global NPP interannual variation (%).Method for calculating contributions of regional IAV to global IAV was developed by Ahlström12. Blue and red areas indicate positive and negative contributions, respectively. This map was created using the ArcGIS 10.2 (http://www.esri.com/software/arcgis/arcgis-for-desktop).
Mentions: To quantify the specific contribution of drought-controlled ecosystems to IAV, we employed the index proposed by Ahlström et al.12 to score the contribution of individual regions to IAV in global NPP. Drought-controlled ecosystems were determined as those exhibiting significant SPEI–NPP relationships (P < 0.01). These regions accounted for 29% of global NPP IAV during the study period, although their contribution to the total global NPP during this time (65.7 Pg C year−1) was only 16%. Moreover, drought-controlled ecosystems in the SH accounted for 33% of the global NPP IAV, whereas their total NPP only accounted for 7% of the total global NPP. These results provide further evidence that drought dominates the IAV in global NPP by controlling semi-arid ecosystems, especially in the SH (Fig. 3). Among the investigated biomes, evergreen broadleaf forests contributed to the largest proportion of global NPP IAV, followed by savannas.

Bottom Line: Drought-dominated NPP, which mainly occurs in semi-arid ecosystems, explains 29% of the interannual variation in global NPP, despite its 16% contribution to total global NPP.More surprisingly, drought prone ecosystems in the Southern Hemisphere, which only account for 7% of the total global NPP, contribute to 33% of the interannual variation in global NPP.Our observations support the leading role of semi-arid ecosystems in interannual variability in global NPP and highlight the great impacts of long-term drought on the global carbon cycle.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China.

ABSTRACT
Drought is a main driver of interannual variation in global terrestrial net primary production. However, how and to what extent drought impacts global NPP variability is unclear. Based on the multi-timescale drought index SPEI and a satellite-based annual global terrestrial NPP dataset, we observed a robust relationship between drought and NPP in both hemispheres. In the Northern Hemisphere, the annual NPP trend is driven by 19-month drought variation, whereas that in the Southern Hemisphere is driven by 16-month drought variation. Drought-dominated NPP, which mainly occurs in semi-arid ecosystems, explains 29% of the interannual variation in global NPP, despite its 16% contribution to total global NPP. More surprisingly, drought prone ecosystems in the Southern Hemisphere, which only account for 7% of the total global NPP, contribute to 33% of the interannual variation in global NPP. Our observations support the leading role of semi-arid ecosystems in interannual variability in global NPP and highlight the great impacts of long-term drought on the global carbon cycle.

No MeSH data available.