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| Natura: | Dataset Open Access |
| Lingua: | en |
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PANGAEA
2012
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| Soggetti: | |
| Accesso online: | https://doi.org/10.1594/PANGAEA.837943 |
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| _version_ | 1867170050190868480 |
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| author | Street, Lorna E Shaver, Gauis R Rastetter, Edward B van Wijk, Mark T Kaye, Brooke A Williams, Mathew |
| author_facet | Street, Lorna E Shaver, Gauis R Rastetter, Edward B van Wijk, Mark T Kaye, Brooke A Williams, Mathew |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Arctic vegetation is characterized by high spatial variability in plant functional type (PFT) composition and gross primary productivity (P). Despite this variability, the two main drivers of P in sub-Arctic tundra are leaf area index (LT) and total foliar nitrogen (NT). LT and NT have been shown to be tightly coupled across PFTs in sub-Arctic tundra vegetation, which simplifies up-scaling by allowing quantification of the main drivers of P from remotely sensed LT. Our objective was to test the LT-NT relationship across multiple Arctic latitudes and to assess LT as a predictor of P for the pan-Arctic. Including PFT-specific parameters in models of LT-NT coupling provided only incremental improvements in model fit, but significant improvements were gained from including site-specific parameters. The degree of curvature in the LT-NT relationship, controlled by a fitted canopy nitrogen extinction co-efficient, was negatively related to average levels of diffuse radiation at a site. This is consistent with theoretical predictions of more uniform vertical canopy N distributions under diffuse light conditions. Higher latitude sites had higher average leaf N content by mass (NM), and we show for the first time that LT-NT coupling is achieved across latitudes via canopy-scale trade-offs between NM and leaf mass per unit leaf area (LM). Site-specific parameters provided small but significant improvements in models of P based on LT and moss cover. Our results suggest that differences in LT-NT coupling between sites could be used to improve pan-Arctic models of P and we provide unique evidence that prevailing radiation conditions can significantly affect N allocation over regional scales. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_837943 |
| institution | PANGAEA |
| language | en |
| publishDate | 2012 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | (Table 3) Leaf area and leaf nitrogen for deciduous, evergreen, forb and graminoid species at Barrow, Svalbard and Zackenberg Street, Lorna E Shaver, Gauis R Rastetter, Edward B van Wijk, Mark T Kaye, Brooke A Williams, Mathew Area/locality; Barrow_plain; Barrow, Alaska, USA; Biological sample; BIOS; International Polar Year (2007-2008); IPY; Latitude of event; Leaf area, specific, per mass dry weight; Longitude of event; MULT; Multiple investigations; Nitrogen, organic; Nitrogen, standard deviation; Nitrogen per area; Sample amount; Species; Standard deviation; Svalbard; Vegetation type; ZAC; Zackenberg; Zackenberg, Northeast Greenland Arctic vegetation is characterized by high spatial variability in plant functional type (PFT) composition and gross primary productivity (P). Despite this variability, the two main drivers of P in sub-Arctic tundra are leaf area index (LT) and total foliar nitrogen (NT). LT and NT have been shown to be tightly coupled across PFTs in sub-Arctic tundra vegetation, which simplifies up-scaling by allowing quantification of the main drivers of P from remotely sensed LT. Our objective was to test the LT-NT relationship across multiple Arctic latitudes and to assess LT as a predictor of P for the pan-Arctic. Including PFT-specific parameters in models of LT-NT coupling provided only incremental improvements in model fit, but significant improvements were gained from including site-specific parameters. The degree of curvature in the LT-NT relationship, controlled by a fitted canopy nitrogen extinction co-efficient, was negatively related to average levels of diffuse radiation at a site. This is consistent with theoretical predictions of more uniform vertical canopy N distributions under diffuse light conditions. Higher latitude sites had higher average leaf N content by mass (NM), and we show for the first time that LT-NT coupling is achieved across latitudes via canopy-scale trade-offs between NM and leaf mass per unit leaf area (LM). Site-specific parameters provided small but significant improvements in models of P based on LT and moss cover. Our results suggest that differences in LT-NT coupling between sites could be used to improve pan-Arctic models of P and we provide unique evidence that prevailing radiation conditions can significantly affect N allocation over regional scales. |
| title | (Table 3) Leaf area and leaf nitrogen for deciduous, evergreen, forb and graminoid species at Barrow, Svalbard and Zackenberg |
| topic | Area/locality; Barrow_plain; Barrow, Alaska, USA; Biological sample; BIOS; International Polar Year (2007-2008); IPY; Latitude of event; Leaf area, specific, per mass dry weight; Longitude of event; MULT; Multiple investigations; Nitrogen, organic; Nitrogen, standard deviation; Nitrogen per area; Sample amount; Species; Standard deviation; Svalbard; Vegetation type; ZAC; Zackenberg; Zackenberg, Northeast Greenland |
| url | https://doi.org/10.1594/PANGAEA.837943 |