Low nitrogen availability in the high Arctic represents a major constraint for plant growth, which limits the tundra capacity for carbon retention and determines tundra vegetation types. The limited ...terrestrial nitrogen (N) pool in the tundra is augmented significantly by nesting seabirds, such as the planktivorous Little Auk (Alle alle). Therefore, N delivered by these birds may significantly influence the N cycling in the tundra locally and the carbon budget more globally. Moreover, should these birds experience substantial negative environmental pressure associated with climate change, this will adversely influence the tundra N-budget. Hence, assessment of bird-originated N-input to the tundra is important for understanding biological cycles in polar regions. This study analyzed the stable nitrogen composition of the three main N-sources in the High Arctic and in numerous plants that access different N-pools in ten tundra vegetation types in an experimental catchment in Hornsund (Svalbard). The percentage of the total tundra N-pool provided by birds, ranged from 0-21% in Patterned-ground tundra to 100% in Ornithocoprophilous tundra. The total N-pool utilized by tundra plants in the studied catchment was built in 36% by birds, 38% by atmospheric deposition, and 26% by atmospheric N2-fixation. The stable nitrogen isotope mixing mass balance, in contrast to direct methods that measure actual deposition, indicates the ratio between the actual N-loads acquired by plants from different N-sources. Our results enhance our understanding of the importance of different N-sources in the Arctic tundra and the used methodological approach can be applied elsewhere.
The Sudetes are remarkable for the variety and number of peat bogs which receive nutrients via precipitation from atmospheric deposition as the only source of minerals. As this type of peat bogs with ...a very low buffering capacity is affected in the Sudetes by long-range exhausts from the former Black Triangle, strong response to atmospheric contamination may be expected. Therefore these peat bogs are highly suitable for bioindication purposes. As a result, metal levels in peat and plants should be controlled to evaluate potential ecological damage and to devise treatment strategies. The aim of this study was to evaluate the concentration of Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in species from different plant functional types (PFTs): shrubs, evergreen dwarf shrubs, deciduous dwarf shrubs, tussock sedges, non-tussock sedges, forbs,
Sphagnum
mosses, brown mosses, liverworts, and algae collected from peat bogs of the Izera, Karkonosze, and Bystrzyckie Mountains. PFTs of the Karkonosze peat bogs situated above the upper forest line contained higher metal concentrations than those of the Izera and Bystrzyckie peat bogs from lower altitudes and surrounded by forests. Of all PFTs, the algae
Zygogonium ericetorum
accumulated the highest levels of Fe, Pb, and Zn. The PFTs of Sphagnum mosses were also very effective bioindicators of Cd, Cr, Fe, Hg, and Pb deposition to peat bog ecosystems. Pb, Fe, and Cr found in the examined vascular PFTs originated from atmospheric deposition. The results showed that airborne contaminants, including the ones connected with long-range transport, can make a significant contribution to a load of trace metals in peat bogs located above the upper forest line. These airborne depositions facilitate better recognition of the transport of contaminants carried over great distances and should be taken into account in monitoring and environmental protection programs. In particular, the results, first of all, show the differences in the bioaccumulation of metals in PFTs and their response to trace metal levels in such habitats. Of all PFTs, algae and Sphagnum mosses were the best choices for bioindication of trace metal pollution in ombrotrophic mountain mires. PFTs have not been used so far for investigating ombrotrophic mountain mires in Europe. Thus results of this investigation could be extended to this type of peat bogs in the mountains of Central Europe for better selection of PFTs for bioindication purposes.
This investigation was conducted to identify the content of metals in
Calluna vulgaris
(family
Ericaceae
),
Empetrum nigrum
(family
Ericaceae
),
Festuca vivipara
(family
Poaceae
) and
Thymus praecox
...subsp.
arcticus
(family
Lamiaceae
), as well as in the soils where they were growing in eight geothermal heathlands in Iceland. Investigation into the vegetation of geothermal areas is crucial and may contribute to their proper protection in the future and bring more understanding under what conditions the plants respond to an ecologically more extreme situation. Plants from geothermally active sites were enriched with metals as compared to the same species from non-geothermal control sites (at an average from about 150 m from geothermal activity). The enriched metals consisted of Cd, Co, Cu, Fe and Ni in
C. vulgaris
; Cd, Mn and Ti in
E. nigrum
; Hg and Pb in
F. vivipara
; and Cd, Fe and Hg in
T. praecox
. Notably,
C. vulgaris
,
E. nigrum
,
F. vivipara
and
T. praecox
had remarkably high concentrations of Ti at levels typical of toxicity thresholds. Cd and Pb (except for
C. vulgaris
and
F. vivipara
) were not accumulated in the shoots of geothermal plants.
C. vulgaris
from geothermal and control sites was characterised by the highest bioaccumulation factor (BF) of Ti and Mn;
E. nigrum
and
F. vivipara
by the highest BF of Ti and Cr; and
T. praecox
by the highest BF of Ti and Zn compared to the other elements. In comparison with the other examined species,
F. vivipara
from geothermal sites had the highest concentration of Ti in above-ground parts at any concentration of plant-available Ti in soil.
Patterned grounds are probably the most interesting features produced by natural processes acting on the Earth's surface. Such features occur mainly in polar areas and in high mountains indicating ...that the origin of patterned grounds is related to frost action and cryoturbation. In spite of the many studies concerning the mechanism of the formation and the various forms of patterned grounds, very little attention has been paid to the qualitative and quantitative analyses of their mineral composition, and especially the mineralogy of the clay fraction. The analysis of the mineralogy of clay fraction is very important due to the finest particles (especially clay minerals) may play a crucial role in cryoturbation and cryosegregation as the particles are mainly responsible for accumulation of water and rheological properties of the ground. Thus, the main aim of the present study was to verify the hypothesis that the presence of swelling clay minerals in parent material favors the development of sorted patterned grounds. To verify the hypothesis, the physical, chemical, micromorphological, and qualitative and quantitative mineralogical properties of Cryosols from sorted and unsorted patterned grounds in the Hornsund area (SW Spitsbergen) were determined. The obtained results show that Turbic Cryosols from sorted patterned grounds featuring clear frost cracking, frost segregation, and cryoturbation are characterized by a lack of clearly developed soil horizons, loamy texture and low content of soil organic matter. Haplic Cryosols show better developed soil horizonation and contain lower amounts of the silt and clay fractions, higher content of the sand fraction and soil organic matter in comparison with Turbic Cryosols exhibiting strong cryoturbation. Micromorphological analysis of Turbic Cryosols indicates frost action manifested by a vesicular microstructure; round, oval, and deformed (mammillated) vesicles as dominant voids; vertically-oriented rock fragments; and silt and silt–clay cappings occurring on rock fragments. In addition, the occurrence of Fe–Mn nodules showing a sharp boundary indicates mixing of soil material. Micromorphology of the studied Turbic Cryosols indicates that cryoturbation prevails over cryosegregation. The soil material of the studied Cryosols is composed mainly of quartz, K-feldspar, plagioclase, dioctahedral mica (muscovite and/or illite), biotite, augite, hornblende, garnet, chlorite, swelling clays (smectite, vermiculite), goethite, and in some cases also calcite and traces of kaolinite. Majority of the minerals are most likely primary minerals inherited from parent material due to weak chemical weathering in the severe Arctic climate conditions and relatively young soils. However, weak chemical weathering of biotite and formation of vermiculite and mixed layered clay minerals also take place. Quantitative mineralogical analysis shows that besides texture and moisture, the mineral composition of soil material may also play some role in the susceptibility to cryoturbation and the formation of sorted and unsorted patterned grounds. However, the small differences in mineral content between the studied Turbic Cryosols and Haplic Cryosols indicate that the mineral composition of parent material is not a crucial characteristic responsible for the formation of sorted patterned grounds.
•Soil properties, micromorphology and mineralogy of Cryosols were studied.•Mineral composition of soil plays some role in the susceptibility to cryoturbation.•Mineral composition is not a crucial soil feature affecting formation of patterned ground.•Micromorphology of the soils indicates that cryoturbation prevails over cryosegregation.
The Karkonosze National Park is affected by long-distance metal air transport of anthropogenic contamination as well as by tourist activity. Therefore, concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, ...Pb and Zn were evaluated in soil as well as in vital and non-vital fronds of
Athyrium distentifolium
Opiz collected in the middle of the growing season from glacial cirques in the Karkonosze. Additionally, fronds of the same species turning brown in autumn were collected from the same sampling sites. The health of ferns was impacted by the contents of Co, Cu, Fe, Mn, Ni, Pb and Zn in fronds, which may indicate that
A. distentifolium
uses elements accumulated in its tissues as defence against pathogens. Individuals from higher altitudes contained higher concentrations of Cd, Cu, Ni, Fe and Pb than those from lower altitudes
.
Autumn fronds of
A. distentifolium
contained a significantly higher concentration of Cr, Cu, Fe, Mn and Pb than vital summer fronds, which may indicate sequestration of these elements in senescing fronds probably to remove potentially harmful metals. Non-vital ferns were a better accumulator of Pb than vital ones, while both types of ferns accumulated Mn in a similar way.
We studied the regional ecology of 33 Sphagnum taxa in 37 mires and 141 stands in the Sudety Mountains, central Europe. Five ecological species groups were distinguished based on the occurrence of ...particular species in plant communities and mire stands, and their distribution patterns along water-chemistry gradients. The ordination analysis (CCA) suggests that the most important factors affecting Sphagnum species distribution and abundance in the Sudety mires were moss height above the water level, altitude as well as surface-water pH and conductivity. In ombrotrophic bogs, moss height above the water level was the primary controlling factor. Within minerotrophic mires the distribution of species was mostly limited by pH, conductivity and Ca concentration in surface water. Sphagnum lindbergii, S. jensenii, S. warnstorfii and S. compactum were mostly restricted to the higher elevations from 1405-1430 m a.s.l., whereas S. rubellum. S. palustre and S. fimbriatum were mainly located at 635-830 m a.s.l.
The anthropogenic impact of metals on aquatic environments is a risk for biota, and thus their levels must be controlled.
Callitriche cophocarpa
Sendtn. belongs to a genus with a potential for ...accumulation of elevated metal levels. Thus, it may provide consolidated evidence of contamination. Therefore, the aim of this investigation was to determine Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in this species collected together with water and bottom sediments from rivers with various levels of pollution. Of these rivers, one less polluted and one more polluted was selected for the collection of
C. cophocarpa
for an experiment to compare its Cu and Zn concentration potential. Both metals were supplemented at concentrations 0.01, 0.02, 0.03, 0.05, 0.08 and 0.14 mg L
−1
of Cu as CuSO4 × 5H2O and 0.4, 0.6, 0,9, 1,35, 2.03 and 3.04 mg L
−1
of Zn as ZnSO
4
× 7H
2
O, and in the binary design containing (mg·L
−1
) 0.01Cu + 0.4Zn, 0.02Cu + 0.6Zn, 0.03Cu + 0.9Zn, 0.05Cu + 1.4Zn, 0.08Cu + 2.03 Zn and 0.14Cu + 3.04Zn. The upper concentrations of Cr, Cu, Mn and Zn in
C. cophocarpa
shoots from both types of rivers as well as of Ni and Pb in shoots from more polluted rivers were higher than the values typical for toxicity thresholds with no visible harmful effects, which may indicate accumulation abilities of
C. cophocarpa
for these metals. Both roots and shoots of
C. cophocarpa
may be included in the group of macroconcentrators for bottom sediments with respect to Cd, Co, Cr, Cu, Fe, Mn, Ni and Zn and deconcentrators of Pb. Greater accumulation of most metals in roots than in shoots indicates their restricted mobility and translocation by
C. cophocarpa
to shoots.
C. cophocarpa
from the less polluted river and exposed to all experimental solutions contained significantly higher levels of Cu and Zn than that from the more polluted river exposed to identical experimental solutions. The plants collected from the more polluted river influenced by surplus of metals and living under chemical stress could probably limit further accumulation by developing a resistance mechanism. Cu and Zn contents in
C. cophocarpa
were higher when treated with separate metals than for binary treatment both in the more and less polluted river. Such research presenting the impact of a combination of metals could be important for understanding and explaining the interactions of these elements which may influence their bioavailability in nature as well as importance in the evaluation of the risk of environmental toxicity.
Snow cover is one of the crucial factors influencing the plant distribution in harsh Arctic regions. In tundra environments, wind redistribution of snow leads to a very heterogeneous spatial ...distribution which influences growth conditions for plants. Therefore, relationships between snow cover and vegetation should be analyzed spatially. In this study, we correlate spatial data sets on tundra vegetation types with snow cover information obtained from orthorectification and classification of images collected from a time-lapse camera installed on a mountain summit. The spatial analysis was performed over an area of 0.72 km2, representing a coastal tundra environment in southern Svalbard. The three-year monitoring is supplemented by manual measurements of snow depth, which show a statistically significant relationship between snow abundance and the occurrence of some of the analyzed land cover types. The longest snow cover duration was found on “rock debris” type and the shortest on “lichen-herb-heath tundra”, resulting in melt-out time-lag of almost two weeks between this two land cover types. The snow distribution proved to be consistent over the different years with a similar melt-out pattern occurring in every analyzed season, despite changing melt-out dates related to different weather conditions. The data set of 203 high resolution processed images used in this work is available for download in the supplementary materials.
The role of seabirds as sea-land biovectors of nutrients is well documented. However, no studies have examined whether and how colonial seabirds that differ in diet may influence terrestrial ...vegetation. Therefore, the purpose of the study was to describe and compare plant communities located in the vicinity of the two most common types of seabird colonies in Arctic, occupied by piscivorous or planktivorous species. Within 46 plots arranged in four transects in the vicinity of planktivorous (little auk,
) and piscivorous colonies (mixed colony of Brunnich's guillemot,
, and black-legged kittiwake,
) we measured the following: guano deposition, physical and chemical characteristics of soil, total nitrogen and its stable isotope signatures in soil and plants, ground vegetation cover of vascular plants and mosses, and the occurrence of lichens, algae and cyanobacteria. Using LINKTREE analysis, we distinguished five plant communities, which reflected declining influence along a birds fertilization gradient measured as guano deposition. SIMPROOF test revealed that these communities differed significantly in species composition, with the differences related to total soil nitrogen content and δ
N, distinctive levels of phosphates, potassium and nitrates, and physical soil properties, i.e., pH, conductivity and moisture. The communities were also clearly distinguished by distance from the bird colony. The two colony types promoted development of specific plant communities: the immediate vicinity of the planktivorous colony characterized by a
-
community while under the piscivorous colony a
community was present. Despite the similar size of the colonies and similar magnitude of guano input, differences between ornithogenic communities were connected mostly to phosphate content in the soil. Our results show that the guano input from seabirds which have different diets can affect High Arctic vegetation in specific and more complex ways than previously realized.
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