Hiding in the background: community-level patterns in invertebrate herbivory across the tundra biome

Invertebrate herbivores depend on external temperature for growth and metabolism. Continued warming in tundra ecosystems is proposed to result in increased invertebrate herbivory. However, empirical data about how current levels of invertebrate herbivory vary across the Arctic is limited and generally restricted to a single host plant or a small group of species, so predicting future change remains challenging. We investigated large-scale patterns of invertebrate herbivory across the tundra biome at the community level and explored how these patterns are related to long-term climatic conditions and year-of-sampling weather, habitat characteristics, and aboveground biomass production. Utilizing a standardized protocol, we collected samples from 92 plots nested within 20 tundra sites during summer 2015. We estimated the community-weighted biomass lost based on the total leaf area consumed by invertebrates for the most common plant species within each plot. Overall, invertebrate herbivory was prevalent at low intensities across the tundra, with estimates averaging 0.94% and ranging between 0.02 and 5.69% of plant biomass. Our results suggest that mid-summer temperature influences the intensity of invertebrate herbivory at the community level, consistent with the hypothesis that climate warming should increase plant losses to invertebrates in the tundra. However, most of the observed variation in herbivory was associated with other site level characteristics, indicating that other local ecological factors also play an important role. More details about the local drivers of invertebrate herbivory are necessary to predict the consequences for rapidly changing tundra ecosystems.KeywordsBackground herbivory Biomass loss Climate change Community-weighted average Invertebrate Insects Tundra </div

The Advance of Woody and Shrub Vegetation to the Mountains and Changes in the Composition of Tundra Communities (Poperechnaya Mountain, the Zigalga Mountain Range in the Southern Urals)

Выявление особенностей динамики растительных сообществ горных и зональных тундр крайне актуально в современных условиях климатических изменений. Нами проведена оценка продвижения древесно-кустарниковой растительности выше в горы на Южном Урале на хр. Зигальга с помощью комплекса методов: сравнения разновременных аэрофото- и спутниковых изображений, повторных ландшафтных фотоснимков и изучения возрастной структуры можжевельника сибирского (Juniperus sibirica Burgsd.) на различных высотах над ур. м. Продвижению древесно-кустарниковой растительности на Южном Урале благоприятствовало повышение температуры и количества осадков в зимнее время. Показаны вертикальные и горизонтальные сдвиги верхней сплошной границы редколесий за период с 1958 по 2012 г. Вертикальный сдвиг сплошной границы редколесий составил 0,74 м/год, горизонтальное продвижение сплошной границы редколесий – 0,20 м/год. На основе изучения возрастной структуры J. sibirica установлен факт его продвижения выше в горы в течение последних двух столетий. Изучен флористический состав горно-тундровых сообществ с разной долей участия J. sibirica. Коэффициенты сходства видового состава сосудистых растений горных тундр (0,53-0,88) свидетельствуют об их типологическом сходстве. Вселение J. sibirica приводит к структурным перестройкам. Наблюдаемые тенденции для сообществ сосудистых растений не связаны с высотной приуроченностью. Состав лихеносинузий не зависит от доли участия J. sibirica в составе горно-тундровых сообществ, при этом демонстрирует зависимость от высоты над ур. м. В сообществах нижней высотной группы видовое богатство лишайников и их обилие снижаетсяEstimation of the dynamics of zonal and mountain tundra plant communities is extremely relevant in modern conditions of climate change. This article demonstrates the results of the estimation of woody and shrub vegetation progression to higher mountains at the Zigalga mountain range (the Southern Urals) using various methods: the comparison of aerial and satellite images, the repeated landscape photographs made at different times and also the examination of Juniperus sibirica Burgsd. age structure at different altitudes. The upward shift of woody and shrub vegetation is caused by the air temperature rise and increased precipitation during the winter periods in the Southern Urals. Vertical and horizontal upper limit shifts of open woodland from 1958 to 2012 are demonstrated. The vertical shift was determined to be 0.74 m/year and the horizontal one is 0.20 m/year. Based on the study of J. sibirica age structure, the fact of its advancement to the mountains during the last two centuries has been established. The research has been focused on the floristic composition of the mountain tundra communities with different J. sibirica cover. The floristic composition of the mountain tundra communities demonstrates their typological similarity. Introduction of J. sibirica leads to structural reorganization. The observed trends for vascular plants do not have any correlation with the height above sea level. Species composition of lichen synusia does not depend on J. sibirica cover, but it correlates with the altitude. Species richness and abundance of terrestrial lichens decrease in plant communities located lower on the mountain slop

The Advance of Woody and Shrub Vegetation to the Mountains and Changes in the Composition of Tundra Communities (Poperechnaya Mountain, the Zigalga Mountain Range in the Southern Urals)

Выявление особенностей динамики растительных сообществ горных и зональных тундр крайне актуально в современных условиях климатических изменений. Нами проведена оценка продвижения древесно-кустарниковой растительности выше в горы на Южном Урале на хр. Зигальга с помощью комплекса методов: сравнения разновременных аэрофото- и спутниковых изображений, повторных ландшафтных фотоснимков и изучения возрастной структуры можжевельника сибирского (Juniperus sibirica Burgsd.) на различных высотах над ур. м. Продвижению древесно-кустарниковой растительности на Южном Урале благоприятствовало повышение температуры и количества осадков в зимнее время. Показаны вертикальные и горизонтальные сдвиги верхней сплошной границы редколесий за период с 1958 по 2012 г. Вертикальный сдвиг сплошной границы редколесий составил 0,74 м/год, горизонтальное продвижение сплошной границы редколесий – 0,20 м/год. На основе изучения возрастной структуры J. sibirica установлен факт его продвижения выше в горы в течение последних двух столетий. Изучен флористический состав горно-тундровых сообществ с разной долей участия J. sibirica. Коэффициенты сходства видового состава сосудистых растений горных тундр (0,53-0,88) свидетельствуют об их типологическом сходстве. Вселение J. sibirica приводит к структурным перестройкам. Наблюдаемые тенденции для сообществ сосудистых растений не связаны с высотной приуроченностью. Состав лихеносинузий не зависит от доли участия J. sibirica в составе горно-тундровых сообществ, при этом демонстрирует зависимость от высоты над ур. м. В сообществах нижней высотной группы видовое богатство лишайников и их обилие снижаетсяEstimation of the dynamics of zonal and mountain tundra plant communities is extremely relevant in modern conditions of climate change. This article demonstrates the results of the estimation of woody and shrub vegetation progression to higher mountains at the Zigalga mountain range (the Southern Urals) using various methods: the comparison of aerial and satellite images, the repeated landscape photographs made at different times and also the examination of Juniperus sibirica Burgsd. age structure at different altitudes. The upward shift of woody and shrub vegetation is caused by the air temperature rise and increased precipitation during the winter periods in the Southern Urals. Vertical and horizontal upper limit shifts of open woodland from 1958 to 2012 are demonstrated. The vertical shift was determined to be 0.74 m/year and the horizontal one is 0.20 m/year. Based on the study of J. sibirica age structure, the fact of its advancement to the mountains during the last two centuries has been established. The research has been focused on the floristic composition of the mountain tundra communities with different J. sibirica cover. The floristic composition of the mountain tundra communities demonstrates their typological similarity. Introduction of J. sibirica leads to structural reorganization. The observed trends for vascular plants do not have any correlation with the height above sea level. Species composition of lichen synusia does not depend on J. sibirica cover, but it correlates with the altitude. Species richness and abundance of terrestrial lichens decrease in plant communities located lower on the mountain slop

Hiding in the background: community-level patterns in invertebrate herbivory across the tundra biome

Invertebrate herbivores depend on external temperature for growth and metabolism. Continued warming in tundra ecosystems is proposed to result in increased invertebrate herbivory. However, empirical data about how current levels of invertebrate herbivory vary across the Arctic is limited and generally restricted to a single host plant or a small group of species, so predicting future change remains challenging. We investigated large-scale patterns of invertebrate herbivory across the tundra biome at the community level and explored how these patterns are related to long-term climatic conditions and year-of-sampling weather, habitat characteristics, and aboveground biomass production. Utilizing a standardized protocol, we collected samples from 92 plots nested within 20 tundra sites during summer 2015. We estimated the community-weighted biomass lost based on the total leaf area consumed by invertebrates for the most common plant species within each plot. Overall, invertebrate herbivory was prevalent at low intensities across the tundra, with estimates averaging 0.94% and ranging between 0.02 and 5.69% of plant biomass. Our results suggest that mid-summer temperature influences the intensity of invertebrate herbivory at the community level, consistent with the hypothesis that climate warming should increase plant losses to invertebrates in the tundra. However, most of the observed variation in herbivory was associated with other site level characteristics, indicating that other local ecological factors also play an important role. More details about the local drivers of invertebrate herbivory are necessary to predict the consequences for rapidly changing tundra ecosystems

Hiding in the background: community-level patterns in invertebrate herbivory across the tundra biome

© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Invertebrate herbivores depend on external temperature for growth and metabolism. Continued warming in tundra ecosystems is proposed to result in increased invertebrate herbivory. However, empirical data about how current levels of invertebrate herbivory vary across the Arctic is limited and generally restricted to a single host plant or a small group of species, so predicting future change remains challenging. We investigated large-scale patterns of invertebrate herbivory across the tundra biome at the community level and explored how these patterns are related to long-term climatic conditions and year-of-sampling weather, habitat characteristics, and aboveground biomass production. Utilizing a standardized protocol, we collected samples from 92 plots nested within 20 tundra sites during summer 2015. We estimated the community-weighted biomass lost based on the total leaf area consumed by invertebrates for the most common plant species within each plot. Overall, invertebrate herbivory was prevalent at low intensities across the tundra, with estimates averaging 0.94% and ranging between 0.02 and 5.69% of plant biomass. Our results suggest that mid-summer temperature influences the intensity of invertebrate herbivory at the community level, consistent with the hypothesis that climate warming should increase plant losses to invertebrates in the tundra. However, most of the observed variation in herbivory was associated with other site level characteristics, indicating that other local ecological factors also play an important role. More details about the local drivers of invertebrate herbivory are necessary to predict the consequences for rapidly changing tundra ecosystems