Effects of water-depth and water-level fluctuations on the macroinvertebrate community structure in the littoral zone of lake constance

We investigated the role of water level fluctuation on benthic macroinvertebrate communities of stony littoral habitats located in the Boreal Shield Ecozone. Using the reference condition approach (RCA), regression analysis, nonmetric multidimensional scaling (NMDS), and analysis of variance (ANOVA), we analyzed the benthic macroinvertebrate community structure of 20 natural lakes and 28 hydroelectric reservoirs to determine if they are structured by change in water level (amplitude). Along a gradient of amplitude intensity, we found that taxa richness decreases with increasing amplitude (r2 = 0.47–0.60). Littoral benthic macroinvertebrate community structure is significantly different in reservoirs that experience amplitudes > 2.0 m. Out of 28 reservoirs, 13 fell outside the 95.5% confidence ellipse determined by 20 reference lakes. Functional mobility group and functional feeding group composition are also altered with increasing amplitude (nonparametric ANOVA, P < 0.05). Further, a change in benthic macroinvertebrate functional composition occurs after a change in taxa richness. Interestingly, reservoirs that experienced amplitudes < 2.0 m had benthic macroinvertebrate communities whose structural and functional composition is similar to lakes experiencing natural water level fluctuations.

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Effects of Water Depth on the Growth of the Submerged Macrophytes Vallisneria natans and Hydrilla verticillata: Implications for Water Level Management

Water ◽

10.3390/w13182590 ◽

2021 ◽

Vol 13 (18) ◽

pp. 2590

Author(s):

Qisheng Li ◽

Yanqing Han ◽

Kunquan Chen ◽

Xiaolong Huang ◽

Kuanyi Li ◽

...

Keyword(s):

Water Level ◽

Water Depth ◽

Deep Water ◽

Submerged Macrophytes ◽

Hydrilla Verticillata ◽

Water Level Fluctuations ◽

Total Biomass ◽

Intermediate Water ◽

Factors Affecting ◽

Vallisneria Natans

Water level is one of the most important factors affecting the growth of submerged macrophytes in aquatic ecosystems. The rosette plant Vallisneria natans and the erect plant Hydrilla verticillata are two common submerged macrophytes in lakes of the middle and lower reaches of the Yangtze River, China. How water level fluctuations affect their growth and competition is still unknown. In this study, three water depths (50 cm, 150 cm, and 250 cm) were established to explore the responses in growth and competitive patterns of the two plant species to water depth under mixed planting conditions. The results show that, compared with shallow water conditions (50 cm), the growth of both submerged macrophytes was severely suppressed in deep water depth (250 cm), while only V. natans was inhibited under intermediate water depth (150 cm). Moreover, the ratio of biomass of V. natans to H. verticillata gradually increased with increasing water depth, indicating that deep water enhanced the competitive advantage of V. natans over H.verticillata. Morphological adaptation of the two submerged macrophytes to water depth was different. With increasing water depth, H. verticillata increased its height, at the cost of reduced plant numbers to adapt to poor light conditions. A similar strategy was also observed in V. natans, when water depth increased from 50 cm to 150 cm. However, both the plant height and number were reduced at deep water depth (250 cm). Our study suggests that water level reduction in lake restoration efforts could increase the total biomass of submerged macrophytes, but the domination of key plants, such as V. natans, may decrease.

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Assessing macroinvertebrate communities in relation to environmental variables: the case of Sambandou wetlands, Vhembe Biosphere Reserve

Applied Water Science ◽

10.1007/s13201-019-1103-9 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 3

Author(s):

Tatenda Dalu ◽

Rivoningo Chauke

Keyword(s):

Community Structure ◽

Water Depth ◽

Environmental Variables ◽

Anthropogenic Activities ◽

Biosphere Reserve ◽

High Water ◽

Macroinvertebrate Community ◽

Macroinvertebrate Communities ◽

Negative Effect ◽

Macrophyte Cover

AbstractThe Vhembe Biosphere Reserve, South Africa, contains many wetlands that serve as wildlife habitats and provide vital ecosystem services. Some of the wetlands are continuously being degraded or destroyed by anthropogenic activities causing them to disappear at an alarming rate. Benthic macroinvertebrates are known as good water quality bioindicators and are used to assess aquatic ecosystem health. The current study investigated habitat quality using macroinvertebrate community structure and other biotic variables (i.e. phytoplankton, macrophytes) in relation to environmental variables in the Sambandou wetlands using canonical correspondence analysis (CCA). A total of fifteen macroinvertebrate families were identified over two seasons. The CCA highlighted seven variables, i.e. pH, phosphate concentration, temperature, ammonium, macrophyte cover, conductivity and water depth, which were significant in structuring macroinvertebrate community. Picophytoplankton and microphytoplankton concentrations decreased from winter to summer, whereas nanophytoplankton concentration increased from winter to summer. Thus, the dominance of small-sized phytoplankton indicated nutrient limitation and decreased productivity, whereas winter sites 2 and 3 were dominated by large-celled phytoplankton, highlighting increased productivity. Winter sites were mostly negatively associated with CCA axis 1 and were characterised by high temperature, phosphate and ammonium concentrations, macrophyte cover, pH and conductivity. Summer sites were positively associated with axis 1, being characterised by high water depth and pH levels. The results obtained highlighted that agricultural activities such as cattle grazing and crop farming and sand mining/poaching had a negative effect on macroinvertebrate community structure.

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Effects of nutrients and water levels on emergent macrophyte biomass in a prairie marsh

Canadian Journal of Botany ◽

10.1139/b90-127 ◽

1990 ◽

Vol 68 (5) ◽

pp. 1007-1014 ◽

Cited By ~ 32

Author(s):

Christopher Neill

Keyword(s):

Water Level ◽

Nutrient Limitation ◽

Water Depth ◽

Nitrogen Limitation ◽

Water Levels ◽

Water Level Fluctuations ◽

Depth Range ◽

Dry Conditions ◽

Second Year ◽

Water Depths

Nitrogen and phosphorus fertilizers were added over two growing seasons to marshes dominated by whitetop grass (Scolochloa festucacea) or cattail (Typha glauca) in a prairie lacustrine marsh to assess nutrient limitation and the interaction of nutrient limitation with water depth. For each species, stands were selected at the deep and shallow extremes of its water depth range. Water levels were high during the first year of fertilization and low during the second year, exposing the fertilized stands to a variety of water depths. Nitrogen limited growth in whitetop and cattail marshes. Water level, by controlling whether the soil was flooded or the water table was below the soil surface, affected growth and the degree of nitrogen limitation. In whitetop marshes, nitrogen increased biomass more when the soil was flooded or when standing water was deeper and in cattail marshes, it increased biomass more under intermediate water depths (approximately 0–20 cm) than under more deeply flooded (20–40 cm) or dry conditions. Nitrogen reduced biomass in whitetop marshes the second year, apparently because growth was inhibited by fallen litter from the previous year. Nitrogen did not limit cattail marsh biomass in the driest locations during a year of low water levels. Phosphorus caused a small increase in growth of both species after 2 years. Changes of nitrogen limitation with flooding suggest that annual water level fluctuations, by creating alternating flooded and dry conditions, may influence the primary production of emergent macrophytes through effects on nitrogen cycling.

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Water physicochemistry and benthic macroinvertebrate communities in a tropical reservoir: The role of water level fluctuations and water depth

Limnologica ◽

10.1016/j.limno.2015.10.002 ◽

2015 ◽

Vol 55 ◽

pp. 13-20 ◽

Cited By ~ 5

Author(s):

Francis S. Magbanua ◽

Nikki Yvette B. Mendoza ◽

Christine Jewel C. Uy ◽

Christoph D. Matthaei ◽

Perry S. Ong

Keyword(s):

Water Level ◽

Water Depth ◽

Water Level Fluctuations ◽

Benthic Macroinvertebrate ◽

Macroinvertebrate Communities ◽

Tropical Reservoir

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Water level fluctuations as a major determinant of chironomid community structure in the inshore zone of a large temperate river

River Systems ◽

10.1127/lr/11/1996/3 ◽

1996 ◽

Vol 11 (1) ◽

pp. 3-9

Author(s):

W. Reckendorfer ◽

H. Keckeis ◽

G. Winkler ◽

F. Schiemer

Keyword(s):

Community Structure ◽

Water Level ◽

Major Determinant ◽

Water Level Fluctuations ◽

Chironomid Community ◽

Temperate River

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Water Level Fluctuation Requirements of Emergent Macrophyte Typha angustifolia L.

Water ◽

10.3390/w12010127 ◽

2019 ◽

Vol 12 (1) ◽

pp. 127

Author(s):

Zhen-Dong Yang ◽

Sai-Bo Yuan ◽

Xue-Qin Liu ◽

Hong-Zhu Wang

Keyword(s):

Life History ◽

Water Level ◽

Water Depth ◽

Tolerance Limit ◽

Seedling Stage ◽

Water Level Fluctuations ◽

Typha Angustifolia ◽

Level Fluctuation ◽

Yangtze Floodplain ◽

Upper Tolerance Limit

The management of water levels in wetlands is of great importance for the wetland ecosystem, including the conservation and revitalization of plants. However, the water level requirements (WLRs) of wetland plants have not been well investigated. In this study, Typha angustifolia was selected as an experimental plant species. Combining field investigation and simulation experiments, the relationship between the development status of this species and water level fluctuations (WLFs) in different life-history stages were analyzed. The results show that populations in the Yangtze floodplain, China, had two phenotypic forms ‘tall’ and ‘short’, and that these were distributed in lakes with intermittent or quasi-natural fluctuations and reservoir-like fluctuations, respectively. Lakes with high amplitude (>3.2 m) water fluctuations did not contain T. angustifolia. We investigated the distribution and growth of T. angustifolia in lakes of varying hydrology across the Yangtze floodplain, seeking to define its tolerance of water-level fluctuations and submergence at different stages in its life cycle. The upper tolerance limit of static submerged water depth was bounded by 1.5 times the height of plants in the seedling stage, and the upper tolerance limit of the submergence rate in the seedling stage was the average growth rate of seedling, 1.5 cm/d. The plant height had a positive linear correlation with amplitude and water depth from June to July. The autumn biomass was significantly negatively correlated with amplitude and water depth from January to May. This paper is perhaps the first case study on water level fluctuation requirements (WLFRs) of emergent macrophytes. It systematically assessed the WLFRs of T. angustifolia in each life-history stage, and established a comprehensive WLFR conceptual model. The results of this study could provide a quantitative operational basis for the protection and restoration of this species in Yangtze floodplain lakes.

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