Sammanfattning

Chronic, low intensity herbivory by invertebrates, termed background herbivory, has been understudied in tundra, yet its impacts are likely to increase in a warmer Arctic. The magnitude of these changes is however hard to predict as we know little about the drivers of current levels of invertebrate herbivory in tundra. We assessed the intensity of invertebrate herbivory on a common tundra plant, the dwarf birch (Betula glandulosa-nana complex), and investigated its relationship to latitude and climate across the tundra biome. Leaf damage by defoliating, mining and gall-forming invertebrates was measured in samples collected from 192 sites at 56 locations. Our results indicate that invertebrate herbivory is nearly ubiquitous across the tundra biome but occurs at low intensity. On average, invertebrates damaged 11.2% of the leaves and removed 1.4% of total leaf area. The damage was mainly caused by external leaf feeders, and most damaged leaves were only slightly affected (12% leaf area lost). Foliar damage was consistently positively correlated with mid-summer (July) temperature and, to a lesser extent, precipitation in the year of data collection, irrespective of latitude. Our models predict that, on average, foliar losses to invertebrates on dwarf birch are likely to increase by 6-7% over the current levels with a 1 degrees C increase in summer temperatures. Our results show that invertebrate herbivory on dwarf birch is small in magnitude but given its prevalence and dependence on climatic variables, background invertebrate herbivory should be included in predictions of climate change impacts on tundra ecosystems.

Nyckelord

Background insect herbivory; Climate change; Externally feeding defoliators; Latitudinal Herbivory Hypothesis; Leaf damage; Leaf miners; Gall makers; Macroecological pattern

Publicerad i

Polar Biology
2017, Volym: 40, nummer: 11, sidor: 2265-2278
Utgivare: SPRINGER

SLU författare

• Hallinger, Martin

  • Institutionen för ekologi, Sveriges lantbruksuniversitet
    

Associerade SLU-program

SLU Nätverk växtskydd


Globala målen

SDG15 Skydda, återställa och främja ett hållbart nyttjande av landbaserade ekosystem, hållbart bruka skogar, bekämpa ökenspridning, hejda och vrida tillbaka markförstöringen samt hejda förlusten av biologisk mångfald
SDG13 Vidta omedelbara åtgärder för att bekämpa klimatförändringarna och dess konsekvenser


UKÄ forskningsämne

Ekologi


More information

Correction in: Polar Biology, 2018, Volume 41: 1653. DOI: 10.1007/s00300-018-2305-6


Publikationens identifierare

DOI: https://doi.org/10.1007/s00300-017-2139-7

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/93254