Species-specific effects of passive warming in an Antarctic moss system

Polar systems are experiencing rapid climate change and the high sensitivity of these Arctic and Antarctic ecosystems make them especially vulnerable to accelerated ecological transformation. In Antarctica, warming results in a mosaic of ice-free terrestrial habitats dominated by a diverse assemblage of cryptogamic plants (i.e. mosses and lichens). Although these plants provide key habitat for a wide array of microorganisms and invertebrates, we have little understanding of the interaction between trophic levels in this terrestrial ecosystem and whether there are functional effects of plant species on higher trophic levels that may alter with warming. Here, we used open top chambers on Fildes Peninsula, King George Island, Antarctica, to examine the effects of passive warming and moss species on the abiotic environment and ultimately on higher trophic levels. For the dominant mosses, Polytrichastrum alpinum and Sanionia georgicouncinata , we found species-specific effects on the abiotic environment, including moss canopy temperature and soil moisture. In addition, we found distinct shifts in sexual expression in P . alpinum plants under warming compared to mosses without warming, and invertebrate communities in this moss species were strongly correlated with plant reproduction. Mosses under warming had substantially larger total invertebrate communities, and some invertebrate taxa were influenced differentially by moss species. However, warmed moss plants showed lower fungal biomass than control moss plants, and fungal biomass differed between moss species. Our results indicate that continued warming may impact the reproductive output of Antarctic moss species, potentially altering terrestrial ecosystems dynamics from the bottom up. Understanding these effects requires clarifying the foundational, mechanistic role that individual plant species play in mediating complex interactions in Antarctica's terrestrial food webs.

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Long-term effects of snowmelt timing and climate warming on phenology, growth and reproductive effort of arctic tundra plant species

Arctic Science ◽

10.1139/as-2021-0028 ◽

2021 ◽

Author(s):

Esther R. Frei ◽

Greg H.R. Henry

Keyword(s):

Plant Species ◽

Reproductive Effort ◽

High Arctic ◽

Snow Accumulation ◽

The Arctic ◽

Plant Responses ◽

Long Term Effects ◽

Passive Warming ◽

Species Specific

Arctic regions are particularly affected by rapidly rising temperatures and altered snow regimes. Snowmelt timing depends on spring temperatures and winter snow accumulation. Scenarios for the Arctic include both decreases and increases in snow accumulation. Predictions of future snowmelt timing are thus difficult and experimental evidence for ecological consequences is scarce. In 1995, a long-term factorial experiment was set up in a High Arctic evergreen shrub heath community on Ellesmere Island, Canada. We investigated how snow removal, snow addition and passive warming affected phenology, growth and reproductive effort of the four common tundra plant species Cassiope tetragona, Dryas integrifolia, Luzula arctica and Papaver radicatum. Timing of flowering and seed maturation as well as flower production were more strongly influenced by the combined effects of snowmelt timing and warming in the two shrub species than in the two herbaceous species. Warming effects persisted over the course of the growing season and resulted in increased shrub growth. Moreover, the long-term trend of increasing growth in two species suggests that ambient warming promotes tundra plant growth. Our results confirm the importance of complex interactions between temperature and snowmelt timing in driving species-specific plant responses to climate change in the Arctic.

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Water’s path from moss to soil: A multi-methodological study on water absorption and evaporation of soil-moss combinations

Journal of Hydrology and Hydromechanics ◽

10.2478/johh-2021-0021 ◽

2021 ◽

Vol 69 (4) ◽

pp. 421-435

Author(s):

Sonja M. Thielen ◽

Corinna Gall ◽

Martin Ebner ◽

Martin Nebel ◽

Thomas Scholten ◽

...

Keyword(s):

Water Absorption ◽

Water Exchange ◽

Methodological Study ◽

Area Index ◽

Moss Species ◽

Specific Effects ◽

Maximum Water ◽

Structural Traits ◽

Species Specific ◽

Soil Substrates

Abstract Mosses are often overlooked; however, they are important for soil-atmosphere interfaces with regard to water exchange. This study investigated the influence of moss structural traits on maximum water storage capacities (WSCmax) and evaporation rates, and species-specific effects on water absorption and evaporation patterns in moss layers, moss-soil-interfaces and soil substrates using biocrust wetness probes. Five moss species typical for Central European temperate forests were selected: field-collected Brachythecium rutabulum, Eurhynchium striatum, Oxyrrhynchium hians and Plagiomnium undulatum; and laboratory-cultivated Amblystegium serpens and Oxyrrhynchium hians. WSCmax ranged from 14.10 g g−1 for Amblystegium serpens (Lab) to 7.31 g g−1 for Plagiomnium undulatum when immersed in water, and 11.04 g g−1 for Oxyrrhynchium hians (Lab) to 7.90 g g−1 for Oxyrrhynchium hians when sprayed, due to different morphologies depending on the growing location. Structural traits such as high leaf frequencies and small leaf areas increased WSCmax. In terms of evaporation, leaf frequency displayed a positive correlation with evaporation, while leaf area index showed a negative correlation. Moisture alterations during watering and desiccation were largely controlled by species/substrate-specific patterns. Generally, moss cover prevented desiccation of soil surfaces and was not a barrier to infiltration. To understand water’s path from moss to soil, this study made a first contribution.

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Soil lichens have species-specific effects on the seedling emergence of three gypsophile plant species

Journal of Arid Environments ◽

10.1016/j.jaridenv.2006.12.019 ◽

2007 ◽

Vol 70 (1) ◽

pp. 18-28 ◽

Cited By ~ 54

Author(s):

A. Escudero ◽

I. Martínez ◽

A. de la Cruz ◽

M.A.G. Otálora ◽

F.T. Maestre

Keyword(s):

Plant Species ◽

Seedling Emergence ◽

Specific Effects ◽

Species Specific

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Density-dependent and species-specific effects on self-organization modulate the resistance of mussel bed ecosystems to hydrodynamic stress

The American Naturalist ◽

10.1086/713738 ◽

2021 ◽

Author(s):

Gerardo I. Zardi ◽

Katy Rebecca Nicastro ◽

Christopher D. McQuaid ◽

Monique de Jager ◽

Johan van de Koppel ◽

...

Keyword(s):

Self Organization ◽

Mussel Bed ◽

Hydrodynamic Stress ◽

Density Dependent ◽

Specific Effects ◽

Species Specific

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Variability in nitrogen-derived trophic levels of Arctic marine biota

Polar Biology ◽

10.1007/s00300-020-02782-4 ◽

2020 ◽

Author(s):

Renske P. J. Hoondert ◽

Nico W. van den Brink ◽

Martine J. van den Heuvel-Greve ◽

Ad M. J. Ragas ◽

A. Jan Hendriks

Keyword(s):

Stable Isotopes ◽

Enrichment Factors ◽

Trophic Levels ◽

The Arctic ◽

Marine Biota ◽

Arctic Ecosystems ◽

Arctic Species ◽

Single Region ◽

Benthic Food ◽

Species Specific

AbstractStable isotopes are often used to provide an indication of the trophic level (TL) of species. TLs may be derived by using food-web-specific enrichment factors in combination with a representative baseline species. It is challenging to sample stable isotopes for all species, regions and seasons in Arctic ecosystems, e.g. because of practical constraints. Species-specific TLs derived from a single region may be used as a proxy for TLs for the Arctic as a whole. However, its suitability is hampered by incomplete knowledge on the variation in TLs. We quantified variation in TLs of Arctic species by collating data on stable isotopes across the Arctic, including corresponding fractionation factors and baseline species. These were used to generate TL distributions for species in both pelagic and benthic food webs for four Arctic areas, which were then used to determine intra-sample, intra-study, intra-region and inter-region variation in TLs. Considerable variation in TLs of species between areas was observed. This is likely due to differences in parameter choice in estimating TLs (e.g. choice of baseline species) and seasonal, temporal and spatial influences. TLs between regions were higher than the variance observed within regions, studies or samples. This implies that TLs derived within one region may not be suitable as a proxy for the Arctic as a whole. The TL distributions derived in this study may be useful in bioaccumulation and climate change studies, as these provide insight in the variability of trophic levels of Arctic species.

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Effect of Soil Diversity on Forest Plant Species Abundance: A Case Study from Central-European Highlands

Forests ◽

10.3390/f12050534 ◽

2021 ◽

Vol 12 (5) ◽

pp. 534

Author(s):

Pavel Samec ◽

Jiří Volánek ◽

Miloš Kučera ◽

Pavel Cudlín

Keyword(s):

Soil Properties ◽

Plant Species ◽

Plant Diversity ◽

Species Abundance ◽

Plant Distribution ◽

Soil Diversity ◽

Abiotic Environment ◽

Soil Group ◽

Biogeographical Regions ◽

Forest Distribution

Plant distribution is most closely associated with the abiotic environment. The abiotic environment affects plant species’ abundancy unevenly. The asymmetry is further deviated by human interventions. Contrarily, soil properties preserve environmental influences from the anthropogenic perturbations. The study examined the supra-regional similarities of soil effects on plant species’ abundance in temperate forests to determine: (i) spatial relationships between soil property and forest-plant diversity among geographical regions; (ii) whether the spatial dependencies among compared forest-diversity components are influenced by natural forest representation. The spatial dependence was assessed using geographically weighted regression (GWR) of soil properties and plant species abundance from forest stands among 91 biogeographical regions in the Czech Republic (Central Europe). Regional soil properties and plant species abundance were acquired from 7550 national forest inventory plots positioned in a 4 × 4 km grid. The effect of natural forests was assessed using linear regression between the sums of squared GWR residues and protected forest distribution in the regions. Total diversity of forest plants is significantly dependent on soil-group representation. The soil-group effect is more significant than that of bedrock bodies, most of all in biogeographical regions with protected forest representation >50%. Effects of soil chemical properties were not affected by protected forest distribution. Spatial dependency analysis separated biogeographical regions of optimal forest plant diversity from those where inadequate forest-ecosystem diversity should be increased alongside soil diversity.

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Variation in vegetation cover and seedling performance of tree species in a forest-savanna ecotone

Journal of Tropical Ecology ◽

10.1017/s0266467418000469 ◽

2019 ◽

Vol 35 (2) ◽

pp. 74-82 ◽

Cited By ~ 2

Author(s):

Hamza Issifu ◽

George K. D. Ametsitsi ◽

Lana J. de Vries ◽

Gloria Djaney Djagbletey ◽

Stephen Adu-Bredu ◽

...

Keyword(s):

Vegetation Cover ◽

Seedling Recruitment ◽

Seedling Survival ◽

Tree Cover ◽

First Year ◽

Transplant Experiment ◽

Tree Seedling ◽

Savanna Woodland ◽

Specific Effects ◽

Species Specific

AbstractDifferential tree seedling recruitment across forest-savanna ecotones is poorly understood, but hypothesized to be influenced by vegetation cover and associated factors. In a 3-y-long field transplant experiment in the forest-savanna ecotone of Ghana, we assessed performance and root allocation of 864 seedlings for two forest (Khaya ivorensis and Terminalia superba) and two savanna (Khaya senegalensis and Terminalia macroptera) species in savanna woodland, closed-woodland and forest. Herbaceous vegetation biomass was significantly higher in savanna woodland (1.0 ± 0.4 kg m−2 vs 0.2 ± 0.1 kg m−2 in forest) and hence expected fire intensities, while some soil properties were improved in forest. Regardless, seedling survival declined significantly in the first-year dry-season for all species with huge declines for the forest species (50% vs 6% for Khaya and 16% vs 2% for Terminalia) by year 2. After 3 y, only savanna species survived in savanna woodland. However, best performance for savanna Khaya was in forest, but in savanna woodland for savanna Terminalia which also had the highest biomass fraction (0.8 ± 0.1 g g−1 vs 0.6 ± 0.1 g g−1 and 0.4 ± 0.1 g g−1) and starch concentration (27% ± 10% vs 15% ± 7% and 10% ± 4%) in roots relative to savanna and forest Khaya respectively. Our results demonstrate that tree cover variation has species-specific effects on tree seedling recruitment which is related to root storage functions.

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