Long-term increases in snow pack elevate leaf N and photosynthesis in Salix arctica: responses to a snow fence experiment in the High Arctic of NW Greenland

We examine the influence of altered winter precipitation on a High Arctic landscape with continuous permafrost. Gas exchange, leaf tissue element and isotopic composition (N, δ13C, δ15N), and plant water sources derived from stem and soil water δ18O were examined in Salix arctica (arctic willow) following a decade of snow-fence-enhanced snow pack in NW Greenland. Study plots in ambient and +snow conditions were sampled in summer 2012. Plants experiencing enhanced snow conditions for 10 years had higher leaf [N], photosynthetic rate, and more enriched leaf δ15N. Enhanced snow did not influence stomatal conductance or depth of plant water use. We attribute the higher photosynthetic rate in S. arctica exposed to deeper snow pack to altered biogeochemical cycles which yielded higher leaf [N] rather than to enhanced water availability. These data demonstrate the complexity of High Arctic plant responses to changes in winter conditions. Furthermore, our data depict the intricate linkages between winter and summer conditions as they regulate processes such as leaf gas exchange that may control water vapor and CO2 feedbacks between arctic tundra and the surrounding atmosphere.

[1]  L Nyström,et al.  Statistical Analysis , 2008, Encyclopedia of Social Network Analysis and Mining.

[2]  A. McGuire,et al.  Controls on ecosystem and root respiration across a permafrost and wetland gradient in interior Alaska , 2013 .

[3]  A. Michelsen,et al.  High arctic heath soil respiration and biogeochemical dynamics during summer and autumn freeze‐in – effects of long‐term enhanced water and nutrient supply , 2012, Global change biology.

[4]  David M. Lawrence,et al.  On the influence of shrub height and expansion on northern high latitude climate , 2012 .

[5]  Rüdiger Gerdes,et al.  Enhanced poleward moisture transport and amplified northern high-latitude wetting trend , 2012 .

[6]  Craig E. Tweedie,et al.  Multi-Decadal Changes in Tundra Environments and Ecosystems: Synthesis of the International Polar Year-Back to the Future Project (IPY-BTF) , 2011, AMBIO.

[7]  T. Callaghan,et al.  Plant and Vegetation Dynamics on Disko Island, West Greenland: Snapshots Separated by Over 40 Years , 2011, AMBIO.

[8]  A. Leffler,et al.  Nitrogen acquisition by annual and perennial grass seedlings: testing the roles of performance and plasticity to explain plant invasion , 2011, Plant Ecology.

[9]  J. Welker,et al.  Evidence of Nonlinearity in the Response of Net Ecosystem CO2 Exchange to Increasing Levels of Winter Snow Depth in the High Arctic of Northwest Greenland , 2011 .

[10]  S. Dullinger,et al.  Late snowmelt delays plant development and results in lower reproductive success in the High Arctic. , 2011, Plant science : an international journal of experimental plant biology.

[11]  G. Schaepman‐Strub,et al.  Shrub expansion may reduce summer permafrost thaw in Siberian tundra , 2010 .

[12]  Kate M. Buckeridge,et al.  Deepened snow increases late thaw biogeochemical pulses in mesic low arctic tundra , 2010 .

[13]  Richard Inger,et al.  Source Partitioning Using Stable Isotopes: Coping with Too Much Variation , 2010, PloS one.

[14]  Sonja Wipf,et al.  A review of snow manipulation experiments in Arctic and alpine tundra ecosystems , 2010 .

[15]  Sonja Wipf,et al.  Phenology, growth, and fecundity of eight subarctic tundra species in response to snowmelt manipulations , 2010, Plant Ecology.

[16]  I. Stirling,et al.  Ecological Dynamics Across the Arctic Associated with Recent Climate Change , 2009, Science.

[17]  Josep Peñuelas,et al.  Global patterns of foliar nitrogen isotopes and their relationships with climate, mycorrhizal fungi, foliar nutrient concentrations, and nitrogen availability. , 2009, The New phytologist.

[18]  Serguei Mankovskii.  Tight Coupling , 2009, Encyclopedia of Database Systems.

[19]  J. Welker,et al.  Nonlinear responses to nitrogen and strong interactions with nitrogen and phosphorus additions drastically alter the structure and function of a high arctic ecosystem , 2008 .

[20]  J. Welker,et al.  Frequent sexual reproduction and high intraspecific variation in Salix arctica: Implications for a terrestrial feedback to climate change in the High Arctic , 2008 .

[21]  J. Welker,et al.  Energy and water additions give rise to simple responses in plant canopy and soil microclimates of a high arctic ecosystem , 2008 .

[22]  C. Osmond.  PHOTOSYNTHESIS AND CARBON ECONOMY OF PLANTS , 2008 .

[23]  Kate M. Buckeridge,et al.  Deepened snow alters soil microbial nutrient limitations in arctic birch hummock tundra , 2008 .

[24]  F. Zwiers,et al.  Human-Induced Arctic Moistening , 2008, Science.

[25]  Paul Grogan,et al.  Landscape and Ecosystem-Level Controls on Net Carbon Dioxide Exchange along a Natural Moisture Gradient in Canadian Low Arctic Tundra , 2008, Ecosystems.

[26]  Steven F. Oberbauer,et al.  The Photosynthetic Response of Alaskan Tundra Plants to Increased Season Length and Soil Warming , 2008 .

[27]  H. Noda,et al.  Photosynthetic characteristics and biomass distribution of the dominant vascular plant species in a high Arctic tundra ecosystem, Ny-Ålesund, Svalbard: implications for their role in ecosystem carbon gain , 2008, Journal of Plant Research.

[28]  Peter M. Lafleur,et al.  Spring warming and carbon dioxide exchange over low Arctic tundra in central Canada , 2007 .

[29]  Steven F. Oberbauer,et al.  TUNDRA CO2 FLUXES IN RESPONSE TO EXPERIMENTAL WARMING ACROSS LATITUDINAL AND MOISTURE GRADIENTS , 2007 .

[30]  W. Wanek,et al.  Natural 15N abundance of soil N pools and N2O reflect the nitrogen dynamics of forest soils , 2007, Plant and Soil.

[31]  J. Welker,et al.  Variation in leaf physiology of Salix arctica within and across ecosystems in the High Arctic: test of a dual isotope (Δ13C and Δ18O) conceptual model , 2007, Oecologia.

[32]  J. Welker,et al.  Modeling the effect of photosynthetic vegetation properties on the NDVI--LAI relationship. , 2006, Ecology.

[33]  J. Kohler,et al.  A long-term Arctic snow depth record from Abisko, northern Sweden, 1913–2004 , 2006 .

[34]  Jeffrey M. Welker,et al.  Leaf mineral nutrition of Arctic plants in response to warming and deeper snow in northern Alaska , 2005 .

[35]  M. Bret-Harte,et al.  Vegetation responses in Alaskan arctic tundra after 8 years of a summer warming and winter snow manipulation experiment , 2005 .

[36]  J. Schimel,et al.  Increased snow depth affects microbial activity and nitrogen mineralization in two Arctic tundra communities , 2004 .

[37]  M. Caldwell,et al.  Gas exchange of four arctic and alpine tundra plant species in relation to atmospheric and soil moisture stress , 1975, Oecologia.

[38]  Mark T. van Wijk,et al.  Tight coupling between leaf area index and foliage N content in arctic plant communities , 2004, Oecologia.

[39]  J. R. Evans.  Photosynthesis and nitrogen relationships in leaves of C3 plants , 2004, Oecologia.

[40]  F. Chapin,et al.  A REGIONAL STUDY OF THE CONTROLS ON WATER VAPOR AND CO2 EXCHANGE IN ARCTIC TUNDRA , 2003 .

[41]  Richard B. Lammers,et al.  Increasing River Discharge to the Arctic Ocean , 2002, Science.

[42]  P. Templer,et al.  Stable Isotopes in Plant Ecology , 2002 .

[43]  E. Russek-Cohen,et al.  Physiological response curve analysis using nonlinear mixed models , 2002, Oecologia.

[44]  Timothy J. G Riffis,et al.  Modelling the interannual variability of net ecosystem CO 2 exchange at a subarctic sedge fen , 2001 .

[45]  S. Korontzi,et al.  A stable isotopic study to determine carbon and nitrogen cycling in a disturbed Southern Californian forest ecosystem , 2000 .

[46]  E. Rastetter,et al.  Vegetation characteristics and primary productivity along an arctic transect: implications for scaling‐up , 1999 .

[47]  P. Brooks,et al.  Snowpack controls on nitrogen cycling and export in seasonally snow-covered catchments , 1999 .

[48]  S. Woodin,et al.  Effects of increased nitrogen and phosphorus availability on the photosynthesis and nutrient relations of three arctic dwarf shrubs from Svalbard , 1994 .

[49]  Catherine Potvin,et al.  THE STATISTICAL ANALYSIS OF ECOPHYSIOLOGICAL RESPONSE CURVES OBTAINED FROM EXPERIMENTS INVOLVING REPEATED MEASURES , 1990 .

[50]  W. D. Billings.  Arctic and Alpine Vegetations: Similarities, Differences, and Susceptibility to Disturbance , 1973 .

[51]  R. D. Black,et al.  Runoff Processes during Snowmelt , 1971 .