Same species, same habitat preferences? The distribution of aquatic plants is not explained by the same predictors in lakes and streams

Use of submergent aquatic plants by North American moose (Alces alces) has been linked to sodium hunger. Habitat preferences, seasonal diets, forage abundance and quality, and population surveys indicated that emergent plants in small shallow ponds were important to moose on the Copper River Delta, Alaska. However, sodium was abundant in terrestrial browse. We propose that foraging in aquatic habitats, particularly on emergent species, may be highly efficient based on the following habitat attributes and behavioral observations: (i) ponds dominated by either emergent or submergent species produced about 4 times more forage than terrestrial habitats, (ii) emergent and submergent plants were more digestible and had higher concentrations of minerals than browse, (iii) use of aquatic habitats followed trends in forage production over the growing season, (iv) indirect evidence suggested that forage intake rates were greater in aquatic habitats, and (v) use of aquatic habitats by male and female moose was in proportion to the sex structure of the population. These data provide consistent circumstantial evidence that use of emergent species, and possibly submergents, may maximize the intake of nutrients and also reduce conflicts between cropping forage and vigilance during a foraging bout.

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Trophic status index of lentic systems from the diversity of aquatic plants from continental Ecuador (IMAE)

Caldasia ◽

10.15446/caldasia.v42n1.77638 ◽

2020 ◽

Vol 42 (1) ◽

pp. 115-128

Author(s):

Esteban Terneus-Jácome ◽

Berenice Vallejo-Solano ◽

Mateo Gómez de la Torre ◽

Christian Larenas-Uría

Keyword(s):

Aquatic Plants ◽

Trophic Status ◽

Environmental Control ◽

Habitat Preferences ◽

Floristic Composition ◽

Indicator Values ◽

Lake Systems ◽

Biological Group ◽

Status Index ◽

Lentic Systems

Aquatic plants are a priority biological group to study due to their high representativeness in ecosystem services and because they also indicate the state of conservation of lake systems. The goal of the study is to develop an Index of Macrophytes from continental Ecuador (IMAE), which can also be applied in the Andean region as a bioindicator, thus assessing the ecological health of the continental lakes and lagoons from 12 to 4000 m, evaluating the structure and floristic composition of aquatic plants and identifying the habitat preferences of the species according to the concentration of nutrients (nitrites, phosphates and ammonium), as determining elements of their presence. 104 species of aquatic plants were found. The tolerance and indicator values have been calculated for each species meanwhile seven levels of coverage were established. Last, four classes of trophic status or water quality were defined to asses lentic systems. The present study will significantly strengthen the environmental control tools for Ecuador.

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Alien aquatic plants in Slovakia over 130 years: historical overview, current distribution and future perspectives

NeoBiota ◽

10.3897/neobiota.49.34318 ◽

2019 ◽

Vol 49 ◽

pp. 37-56

Author(s):

Richard Hrivnák ◽

Jana Medvecká ◽

Peter Baláži ◽

Kateřina Bubíková ◽

Helena Oťaheľová ◽

...

Keyword(s):

Climate Change ◽

Alien Species ◽

Aquatic Plants ◽

Aquatic Plant ◽

Habitat Preferences ◽

Water Bodies ◽

Running Waters ◽

Historical Overview ◽

Artificial Water Bodies ◽

Artificial Water

Alien aquatic plants rank amongst the major threats to aquatic biodiversity and, since ongoing climate change is expected to facilitate their further spread, there is an urgent need for sound knowledge of their distribution and ecology. We collected published and unpublished data spanning the last ~130 years and performed the first comprehensive assessment of alien aquatic vascular plants in Slovakia with the following aims: (i) to prepare a national inventory, (ii) to assess the effects of climate and landscape on species diversity and (iii) to evaluate the habitat preferences of the species. The historical overview showed a strongly increasing trend in the number of alien species related to an increased amount of intensive research of aquatic vegetation over the last 30 years. Altogether, 20 neophyte alien aquatic plant taxa were recorded from 479 sampling sites. However, the species inventory seems to be far from complete and approximately 14 species are expected to remain undetected. Elodeacanadensis and E.nuttallii are the most frequently occurring alien aquatic plants, while eight other species have been found at a single site only. The majority of alien plants were deliberately introduced as aquarium ornamentals or released through pond waste. The fragmented information on local habitat conditions did not allow us to draw firm conclusions about the habitat preferences of alien aquatic plants. However, artificial water bodies are more frequently colonised by alien species than natural habitats (95% of aliens were found in artificial water bodies and 60% of them were recorded exclusively in these habitats) and many species have broad environmental tolerances (ability to colonise both standing and running waters, tolerances to a wide range of temperatures and water chemistry). Our results reaffirm the major role of increased temperatures and landscape modification in the distribution of alien aquatic plants and we can expect enhanced invasiveness and spreading of alien species into new habitats driven by climate change and land use intensification. Filling a main gap in the recognition of alien aquatic plant environmental preferences is a challenge for future research with the ultimate goal of maintaining natural aquatic plant diversity and ecosystem functioning.

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