SEED RAIN AND DISPERSAL POSSIBILITIES BETWEEN PROCESS DOMAINS

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Bachelor thesis, ECTS15 Kandidatexamen i geovetenskap, 15hp

Vt 2018

SEED RAIN AND DISPERSAL

POSSIBILITIES BETWEEN

PROCESS DOMAINS

Comparing seed dispersal abundance

between lakes, rapids and slow-flowing

reaches

Joe Sundin

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Seed rain and dispersal possibilities between process

domains

- Comparing seed dispersal abundance between lakes, rapids and slow- flowing reaches

Joe Sundin

Abstract

Process domains are formed by geomorphological process, these geological formation act as water pathways for river systems and affects hydrochory potential for seeds. Hydrochory acts differently depending on fluvial settings and is an important factor for diversity in the riparian zone along streams and lakes. The aim of this study was to (1) determine if process domains influence plant species abundance and diversity, and (2) if certain environmental factors associated with different process domains affects species abundance and diversity. The sample sites are parts of a dendritic water system located in tributaries for Hjuksån summer 2017 in northern Sweden. Seed samples were collected from three process domains (lake, rapids and slow-flowing) and later identified in lab. A greater species abundances and seed amount were found at lakes compared to rapids and slow-flowing reaches but there were no significant different between the process domains. None of the environmental factors showed to be important but there were indications that number of boulders might influence seed dispersal.

Shannon Diversity index showed to be highest along slow-flowing reaches, but again no significant difference. Understanding process domains and their unique compositions in species abundance and diversity is for example an important factor for restoration techniques of anthropogenic modified streams.

Keywords: Hydrochory, Process Domain, Diversity, Environmental variables, Restoration.

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1 Introduction

Of earth’s surface only 0.08 % is covered by freshwater habitats, which is only 0.01% of the total water volume on earth (Gleick 1996). The riparian zone is a transition between land and water, which contains a unique ecosystem that varies depending on the stream size – from small corridors along streams to kilometer wide floodplains along larger rivers (Kauffman et al. 1997). However, being such a small area, the riparian zone is home to one quarter of all vertebrate species in the world and a vast variety of vascular plants (Lundberg et al. 2000).

Freshwater ecosystems show a steeper decline in biodiversity compared to most affected terrestrial ecosystems (Sala et al. 2000), and still freshwater hotspots in general receive less attention then their terrestrial counterparts (Myers et al. 2000). Riparian zones also act as filters for nutrients, which would otherwise end up in the stream (Dosskey 2010). An increase discharge of the nutrients nitrogen and phosphorus in streams, lakes and estuaries have shown to increase the ecological stress in these ecosystems (Dosskey 2010). Plant roots also absorb to some degree non-nutrient chemicals such as heavy metals (e.g., cadmium, chromium, mercury, nickel, lead), metalloids (e.g., arsenic, selenium) and other elements (e.g. boron, cesium, strontium) (Roca and Vallejo 1995).

Stream networks in northern Sweden are commonly naturally fragmented and characterized by process domain consisting of both slow-flowing (Fig. 1A) rapids reaches (Fig. 1B) and numerous lakes (Fig. 1C) (Nilsson et al. 2002). The term process domains define spatially discrete regions and dynamics along river systems, which are produced through geomorphic processes (Montgomery 1999). The effects on ecological systems are generated by spatial and temporal variability in geomorphic processes, which are correlated to size, frequency and duration of the associated habitat disturbances (Montgomery 1999).

Figure 1. Process domains studied: A) Slow-flowing reaches, B) Rapids reaches and C) Lakes (Lind 2017).

A)

C)

B)

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The riparian zone is shaped by fluvial disturbances, which are generated by variation in landscape topography, water currents and waves (Ward 1997). Rapids have a high slope (0.5- 6%) and the material consists of coarser material such as gravel, cobbles, boulders and bedrock. Only during high floods in low velocity areas sedimentation does occur (Wohl and Cenderelli 2000). In slow-flowing reaches with weaker flow velocity and low channel slope (<0.1%), materials such as sand, silt, clay and fine-particulate organic matter is deposited, which creates floodplain environments. Lakeshores have the same characteristics as slow- flowing waters, but they are more vulnerable to waves and ice which can develop coarser shoreline material (Nilsson et al. 1993; Scrimgeour et al. 1996). This generates a sedimentation sink in stagnant waters from the materials eroded from higher velocity turbulent reaches, which in turn will affect seeds in the streams. These variables and processes creates different ecological habitats for plants and animals and differences in dispersal patterns (Montgomery 1999). For example, vascular plants favor different soil textures, with small-seeded species benefiting from a finer texture material from which the slow-flowing reaches are compositional by, creating different ecological environments between process domains (Keddy and Constabel 1986).

Hydrochory is an important dispersal process for a large proportion of riparian, aquatic, wetland and tidal plant species (Nilsson et al. 2010). With the use of hydrochory, plants can reach and germinate locations, which would otherwise be out of reach with other dispersal vectors (Nilsson et al. 2010). The furthest recorded seed mimics have travelled 152.5 km (Andersson et al. 2000). Seeds in water can disperse in different ways (Parolin 2005) but the ones mostly affected by landscape modification are; (1) nautohydrochory: floating on the water surface or other objects guided by surface currents; (2) bythisochory: dispersal by water currents on the bottom of the stream (Parolin 2005). Hydrochory affects processes for species dispersal mechanics through population establishment, size and longevity, influence genetic diversity within population and the distribution of genetic diversity and divergence among populations (Nilsson et al. 2010).

To understand the floristics patterns for streams and lakes, the dispersal traits for seeds is a very important aspect for species ability to populated new areas (Staniforth and Cavers 1976).

In stream reaches with a higher flow velocity such as rapids, seeds ability to stay afloat diminishes (Danvind and Nilsson 1997). Instead, hydraulic processes disperse seeds towards the banks in turbulent reaches through obstructions in the stream such as boulders and larger woody debris. These objects deflect the water current and seeds can latch onto the banks or protruding vegetation (Nepf 1999). With the force of the turbulent water, even waterlogged and non-buoyant seeds are propelled into suspension. This means that seeds with shorter floating ability are more frequent along the riverbanks with turbulent flow than in slow-flowing reaches (Nilsson et al. 2002). This shows that there are other factors than floating ability that influences the distribution of seeds in streams. However, during high discharges in turbulent reaches, the flow velocity will be reduced and obstructions in the stream will be less hindrance, and surges of water and turbulent waves might then be the dominant factor for dispersing seeds towards the banks (Nilsson et al. 2002). Seeds with low floating ability are less frequent along lakeshores due to the water-wind current differences (Saarnel et al. 2014). This occurs when there is weak water- and strong wind currents so wind becomes the dominant factor for distributing seeds. This can lead to seeds with low floating ability to sink during sporadic wind conditions as they are blown back and forth on the open water (Nilsson et al. 2002). Hence, in stream networks consisting of rapids, slow-flowing reaches and lakes, lakes can act like trapping barriers for seeds which could increase the chance for long floating seeds to germinate but could potentially hinder short floating species from spreading further downstream (Nilsson et al. 2002).

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3 1.1 Objectives

I examined seeds collected from each of the process domains: rapids, slow-flowing and lakes.

The objective was to determine if abundance, diversity and composition of stranded seeds differ depending on the type of process domain. I hypothesized that (1) owing to a higher seed retention in lakes and slow-flowing compared to rapids, the diversity and abundance of seeds should be higher in lakes than in slow-flowing reaches and least in rapids, and (2) that the species composition should be more similar between slow-flowing and lakes than with rapids.

Materials and methods

2.1 Study site

The study is performed in three different process domains, (lakes, rapid and slow-flowing reaches) in the northern Sweden with all of the domains being a part of the 12 km long river Hjuksån, which is a tributary to the Vindel River. Being one of the four national rivers in Sweden, the 450 km long Vindel River and its drainage area of 12 650 km² is protected against hydropower and water diversion to other rivers. It originates in the Scandinavian Mountains at the border between Norway and Sweden and connects with the Ume River 25 km from the coast before it discharges into The Gulf of Bothnia. As with most rivers in the boreal region of northern Sweden, the Vindel River flow increases drastically by 100 times during the spring flood compared to the rest of the year (Länsstyrelsen Västerbotten and

Naturvårdsverket 1997).

Figure 2. Map of the location of study sites (A) Sweden (Google maps 2018), B) Västerbotten (Google maps 2018) and C) Hjuksån tributaries(Lind 2017)) at each process domain (L=lakes, R=rapids and S=Slow-flowing).

N

A

)

B

)

L1 L2

L4 L3

S2 S1 S3 S4 R1

R2

R4 R3

C

)

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4 2.2 Field methods

During summer 2017, three process domains (lakes, rapids and slow-flowing reaches) were studied within the catchment of Hjuksån (Fig. 2). Each process domain was replicated four times and at each site there was five plots distributed across the riparian zone at different elevations to cover as much as possible of the riparian zone. Turf mats (25 x 25 cm) were used to act as seed traps for monitoring the seed rain. The turf mats where arranged in two lines with the mats perpendicular to each other, at 0 cm from water and at 40 cm from the water.

Each transect were separated by 10m since 50 meters was the maximum available distance for some rapids (Fig. 3). The seed traps were left in field from the beginning of summer 2017 and were later collected in August-September 2017. Each turf mat was flushed with water in order to extract the seed deposits, followed by wet-sieving (0.1 mm) and drying at room temperature.

Various environmental variables were measured at each site, bank irregularities, instream islands, wood debris and chaintape (topographic distance of cross sections) was measured using a Trimble S3 tachometer and then calculated in ArcGIS (ESRI 2012). Flow velocity was determined by measuring traveling time using five seed mimics. Wind speed and direction was measured using a compass and anemometer. Instream vegetation and boulders abundance were quantified as 1 (1‒20 %), 2 (21‒40 %), 3 (41‒

60 %), 4 (61‒80 %) and 5 (81‒100 %). These could influence seed rain (Appendix 1)

(Xiaolei 2017). Figure 3. Set-up in field, green squares represents the seed traps (Lind 2017)

2.3 Laboratory methods

In order to get enough seeds identified within the timeframe of the project, only turf mats from transect 1, 3 and 5, at 0 cm from the water from were analysed. Each sample was weighed before the seeds were removed and then again for the total seed biomass for each sample were weighed. The content from each turf mat were emptied into a petridish and the seeds was removed one by one for identification with the use of a microscope. Thereafter, with the help of literature from Cappers (2016), Krok (2012), Mossberg and Stenberg (2010) the seeds were identified and then placed in a plastic container for further research.

2.4 Statistical analysis

All data analysing was done in R (R Development Core Team 2009). The level of significance for this study was set to: α=0.05. To compare the species abundance between each process domain a two-way ANOVA was used. A one-way ANOVA was also used in the same way to examine if there is any difference in seed amount between process domains (Schmider et al.

2010).

The diversity value for each individual process domain was calculated using Shannon diversity index: 𝐻´ = ∑^𝑅_𝑖=1𝑝𝑖(𝑝𝑖) and to see if there was a significant diveristy difference, a one-way ANOVA analysis was performed in R (Schimder et al. 2010).

To see if there were any differences in species composition between each process domain, a Non-metric Multidimensional Scaling (NMDS) was performed using the packages: Vegan (Oksanen et al. 2018) and MASS (Ripley et al. 2002).

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Pearson Correlation coefficients was used to see if any environmental data from the area if could explain any difference in the number of species for each process domain. Species composition were checked against 12 environmental variables (appendix 1). Variables which could have a potential effect and above p>0.70 were used for linear model with an effect on species richness. The least significant variables were removed one by one until only significant variables were left. Some of the turf mats were overgrown with moss and to investigate if moss overgrowing matt turfs could affect seed rain a two-way ANOVA was performed. To see if there was any inclination that there would be more species further down the river system a simple line graph was done in excel, however more data would be needed to perform statistical analysis.

3 Results

In total, 50 plant species were identified based on the seed rain on the turf mats. I found no significant difference in species abundance between the different process domains (p= 0.4623, F=0.8416, df=9) (Fig. 4a). There was neither a significant difference in average number of seeds stranded at each process domain (p=0.1492, F=2.368, df=9) (Fig. 4b).

Figure 4. a) Average number of species for each process domain and b) average number of seeds for each process domain.

a) b)

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I found no difference in species diversity between process domains (Shannon diversity index) (p=0.419, F=0.7106, df=10) (Fig. 4).

Figure 5. Shannon diversity index average for the process domains.

I found no distinct difference for process domain in the NMDS analysis (Fig. 6).

Figure 6. NMDS analysis with polygons representing speices diversity for each process domain.

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Presence of overgrown moss on the mats were not significant (p=0.0557, F=3.925, df=34) (Fig. 7).

Figure 7: Total species for mats covered in moss and non-moss.

Pearson Correlation coefficients shows that none of the environmental data is significantly influencing species abundance. Closest variable to be significant (number of boulders) (p=0.07192, F=2.137, df=9), all other environmental variables were not significant (p>0.1).

Appendix 2 shows species abundances for sample sites depending on their position downstream in the tributary.

4 Discussion

4.1 Species abundance and seed amount

Earlier studies by Nilsson et al. (2002) have shown that slow-flowing reaches and lakes should have a higher seed retention, this is partly explained by the lower flow velocity not being able to dislodge seeds from stream banks. Lakes also acts as barriers in stream systems by being a

“propagule sink” because the transportation in rapids is faster than in slow-flowing water, the seeds should accumulate in slow-flowing waters and increases the abundance of species (Nilsson et al. 2002; Montgomery 1999). However, even though there is greater variety of species in lakes, it might not represent the total amount of seeds reaching lakes since the wind filters out short floating seeds and only long floating seeds are able to reach the lakeshore. The reason for not finding significant differences in this study can be explained by both high and low extreme values in all three process domains (Fig. 4a and 4b). Moss was more common in lakes than rapids and slow-flowing reaches, moss occurrence had a higher species abundance (Fig. 7), however moss is not a suitable substrate to germinate in so most of the seeds stuck would most likely die. Due to time limitation, I only managed to identify about half of the samples from 0 cm from the stream channel, and none of the samples from 40cm above the water surface. Increasing the number of samples would increase the chance of finding a significant difference for species abundance and number of seeds, and I believe that I would have found this pattern supported by earlier research (Nilsson et al. 2002; Keddy and

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Constabel 1986; Hupp 1992; Andersson et al. 2000). When the discharge in turbulent reaches exceeds their normal or intermediate discharges, or when there is a strong enough wind to overwhelm the flow velocity, slow-flowing reaches do not function as propagule sinks anymore.

During these occurrences there is a threshold when slow-flowing reaches have a higher flow velocity than turbulent reaches called “velocity reversal” (Thompson et al. 1999). This could alter the dispersal of seeds for a duration and increase/decrease the amount of seeds with different attributes reaching the banks depending on the process domains.

4.2 Diversity

Riparian zones are one of the most diverse ecosystems in the world with multiple examples as in Santa Monica Mountains in southern California in the United States where the riparian zone and adjacent wetlands cover less than 1% of the total area but almost 20% of the native vascular plant species exists there (Rundel and Sturmer 1998). The same pattern was found in Vindel River in northern Sweden where 13% of the country’s vascular plants were found in its riparian zone (Nilsson 1992). Earlier studies by Nilsson et al. (2000) have found a difference in diversity between process domains which can in parts be explained by seeds floating ability. They found that there was a higher frequency of short floating seeds in turbulent waters than in slow- flowing, the same goes for long floating seeds in slow-flowing waters with 12-20% higher frequency. Similar results were found by Keddy and Constable (1986) showing that long floating seeds belonged mostly to herbs and aquatic species while dwarf shrubs, graminoids and terrestrial species had short floating seeds that further suggests that there should be a diversity difference between process domains. Each process domain is also characterised by different soil textures, which favours different plant communities (Hupp 1990). This also affects variables such as soil moisture, which have shown to have a correlation with phenology of sprouting, seed release and high growth of riparian plants. This would favour a richer plant community around lakes and slow-flowing areas since their reaches consist of a finer texture material (Stella et al. 2006). Based on previous studies, if more samples were to be analysed I would probably find a statistical difference in diversity between process domains. However, if we would not find a significant difference with more samples, we would have to conclude that diversity in the riparian zone is not affected by the factors studied in process domains for this study. This means that more factors controlling dispersal of seeds needs to be taken into account for further research. Slow-flowing reaches did show the highest Shannon diversity index (Fig. 5), this could be explained by slow flowing reaches having a combination of geomorphological and ecological habitats from both rapids and lakes allowing a greater variety of seeds to reach the bank. From the NMDS analysis (Fig. 6) it seems that rapids have a more distinct species composition compared to lakes and slow-flowing reaches. This correlates with my hypothesis that lakes and slow-flowing reaches should favour the same species composition. Since seed attributes are so important for a successful dispersal, it would also be interesting to elaborate this study by analysing the different seed species attributes and see if it has any differences depending on process domains.

4.3 Restoration

Projects to restore the channelized streams to their natural state began shortly after the end of log transport by streams by 1980 and the effort increased further after the 21th century. The main focus has been to re-establish natural spawning habitats for fish in order to increase the existing fish population or to revitalizes them completely (Gardeström et al. 2013). A straighter stream without obstructions causes a reduction of the width and increases the depth of streams, making them more homogenized. Furthermore, the flow velocity is higher in channelized streams which leads to intensification of sediment erosion. All these factors reduce the synergy between the riparian zone and the stream, which affects the hydrochory potential (Nilsson et al. 2005; Helfield et al. 2007). The higher amount of species and seeds found in lakes compared to rapids and slow flowing water in this study (Fig. 4a and 4b) shows that restauration of streams should take hydrochory in consideration when performed. Instead of

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restoring streams to only a meandering state, the restoring process might include creation of all three process domains to increase the species abundance. The change in characteristics for a restored stream is most prominent in flow velocity and flood frequency (Helfield et al. 2007).

This is variation is generated by the revitalization of boulders and larger wood debris back to the stream hinder the flow velocity and disrupts the even flow direction in the channel (Muotka and Laasonen 2002). Boulder numbers in this study was also very close to be a significant factor for species abundance so the method of revitalizing boulders in restoration of streams needs to be accurately performed.

The anthropogenic impact on river systems have occurred for a long period of time which can make it difficult to determine their original characteristics. Historical knowledge is a vital key in remodeling stream to their natural state (Bernhardt and Palmer 2011). However, the rehabilitation for certain streams ecology might be beyond restoration but there is still an increase in projects concerning restoration (Nilsson et al. 2005). There is however a lack of results showing that the goals for restorations are met (Jähnig et al. 2011). This is because evaluating the outcome of restored streams usually ends after a few years due to expenses (Hasselquist et al. 2015).

4.4 Catchment water system

Seed dispersal is affected by factors which are based on channel characteristics, these characteristics are created by geological process (Vorosmarty et al. 2010). Channels usually flow SE towards the coast in northern Sweden in formation caused by the last ice age. However, the tributaries in this study flow towards the NW or SW, this could have an effect on seed dispersal e.g. through wind, since wind direction is downstream when it normally would have been upstream. Network topology has been analysed by Altermatt and Fronhofer (2017) to be as possible factor for species diversity in dendritic water systems and sample sites 1-3 in this study are part of a dendritic water system which could have an impact on species abundance, diversity and species composition downstream (appendix 2).

4.4 Conclusion

Even though I did not find any significant relationships, I can see a trend towards higher seed retention in lakes, and if there were more time to analyse samples there is a possibility that I would have found a significant difference. More samples might also affect the diversity difference (Fig. 5) or strengthen the theory that slow flowing reaches have a higher diversity due to be an intermediate for geomorphological processes between lakes and rapids.

5 Acknowledgements

First of all, I would like to thank my supervisor Lovisa Lind, for giving me the opportunity to do this study, provide me with her field samples, advice and support throughout the project. I also want to thank Judith Saarnel for finding time to help me with her expertise in identifying seeds. Lastly, I want to thank everyone at the department of Ecology and Environmental science for advice and support during our many fika breaks.

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Appendix

Appendix 1. Enviromental data

L1 69 1.65 160 12 323.4 5 1.02 1.72 0 0.22 0 0.26 0 0 0

L2 34.7 1.4 150 15 361.8 5 1.01 1.25 0 0.1 0 0 0 0 0

L3 44.38 1.61 213 18 258.4 5 1.02 1.59 0 0.1 0 0 0 1.6 0

L4 48.69 1.29 207 12 259.9 5 1.03 1.68 0 0.21 0 0 0 0 0

R1 37.6 1.32 30 6 6.22 0.68 1.2 1.33 1.93 1.94 37 58.95 2 384.9 1.19

R2 37.49 5 1.96 96 12 11.74 1.06 1.06 1.17 0.93 1.33 19 28.43 1 37.31 0

R3 48.95 1.61 116 11 7.72 1.09 1.21 1.36 1.66 0.82 26 3.72 2 265.4 1.17

R4 40.35 1.35 52 7 10.91 0.61 1.08 1.09 1.08 0.85 57 27.14 1 82.96 0.63

Sf1 45.91 5 1.28 19 5 15.53 1.3 1.08 1.18 0.11 0.29 0 86.36 3 12.8 0

Sf2 66.61 5 1.53 47 8 19.69 0.86 1.08 2.9 0.1 0.45 0 58.43 5 0 0

Sf3 37.67 1.81 274 18 14.79 1.23 1.08 1.2 0.12 0.27 1 99.61 4 0 0

Sf4 51.92 1.91 64 12 18.02 1.4 1.07 1.5 0.38 0.43 0 67.5 4 15.15 0

Factors Moistavg SW Tot Total seeds Total species Width Depth Chaintape BankIrregularity ChannelSlope FlowVelocity BoulderNumber VegCover VegCover2 LogCover IslandCover

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Appendix 2. Species abundance depending on downstream location.

Appendix 3. Species found in this study.

Species L1 L2 L3 L4 R1 R2 R3 R4 Sf1 Sf2 Sf3 Sf4

Pinus sylvestris 0 2 6 5 4 1 1 0 1 5 0 1

Picea abies 0 1 7 4 0 0 0 0 0 0 0 0

Alnus incana 0 0 1 0 0 0 0 0 0 0 0 0

Fragaria vesca 0 0 0 0 0 0 0 0 0 0 117 8

Stachys palustris 4 0 0 0 0 0 0 0 0 0 1 0

Pedicularis palustris 4 1 1 0 1 0 0 0 0 0 0 0

Empetrum nigrum 0 0 0 0 0 1 0 1 0 0 0 0

Betula pendula 0 1 7 118 3 15 26 20 4 17 12 12

Betula pubescens 1 3 10 39 3 17 3 10 5 4 7 7

Betula nana 0 3 3 16 0 12 10 0 0 7 2 5

Calamagrostis Canescens 1 0 0 0 0 0 0 0 0 0 2 0

Calamagrostis purpurea 0 0 0 0 0 0 0 0 1 0 0 0

Calamagrostis epigejos 0 0 0 0 0 0 0 1 0 2 0 0

Filipendula ulmaria 6 0 0 0 0 0 0 0 0 0 2 0

Carex nigra 34 6 0 0 0 0 0 0 0 0 30 0

Carex canescens 55 56 3 1 12 15 1 0 0 0 6 2

Carex limosa 12 1 0 0 0 0 0 0 0 0 0 0

Carex Aquatilis 5 0 0 3 0 0 0 0 0 0 0 0

Carex acuta 24 55 0 0 0 1 2 2 0 0 35 0

Carex lasiocarpa 0 1 18 3 0 0 9 0 3 0 1 1

Carex chordorrhiza 0 0 5 1 0 0 4 0 0 0 0 0

Carex rostrata 0 0 116 3 0 0 45 10 0 1 15 5

Carex vesicaria 0 0 9 0 0 0 3 0 0 0 0 0

Carex brunnescens 0 0 0 0 0 3 0 0 0 0 0 0

Carex vaginata 1 0 0 0 0 0 0 0 0 0 0 0

Carex diocia 0 1 0 0 0 0 0 0 0 0 0 0

Carex magellanica 0 0 2 0 0 0 0 0 0 0 1 0

Carex cespitosa 0 0 0 0 0 0 0 0 0 0 1 0

Carex buxbaumii 0 0 0 0 0 0 0 0 0 0 1 0

0 2 4 6 8 10 12 14 16 18 20

1 2 3

Number of species

Location in the stream network

Lake Sel

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Luzula pilosa 0 0 0 0 0 6 0 0 0 0 0 0

Luzula sudetica 0 0 0 0 0 1 0 0 0 0 0 0

Viola tricolor 0 0 0 0 0 7 0 0 0 0 0 0

Viola palustris 0 0 0 0 0 5 0 0 0 0 18 0

Viola epipsila 0 0 0 0 0 0 0 0 0 0 1 1

Juncus filiformis 0 1 0 0 0 0 0 0 0 0 0 0

Juncus balticus 0 0 0 0 0 0 0 0 0 1 0 0

Festuca pratensis 0 0 0 0 0 0 0 0 0 2 0 0

Festuca ovina 0 2 0 0 0 0 0 0 0 0 0 0

Molinia caerulea 1 0 0 0 0 0 0 0 0 0 0 0

Menyanthes trifoliata 0 1 1 0 0 0 0 0 0 0 0 0

Peucedanum palustre 0 0 1 0 0 0 0 0 0 0 0 0

Valeriana sambucifolia 0 0 0 0 1 0 0 0 0 0 4 1

Brassica rapa 0 0 0 0 0 0 1 0 0 0 0 0

Calluna vulgaris 0 0 1 0 0 0 0 0 0 0 0 0

Comarum palustris 0 0 3 0 0 0 0 0 0 0 0 1

Trifolium hybridum 0 0 0 1 0 0 0 0 0 0 0 8

Geranium sylvaticum 0 0 0 0 0 0 0 1 0 0 0 0

scheuchzeria palustris 0 0 1 0 0 0 0 0 0 0 0 0

Maianthemum bifolium 0 0 0 1 0 0 0 0 0 0 0 0