2012
Furey, Paula C.; Lowe, Rex L.; Power, Mary E.; Campbell-Craven, Alexis M.
Cladophora, and epiphytes: shifting interactions through succession Journal Article
In: Freshwater Science, vol. 31, no. 1, pp. 93-107, 2012.
Abstract | Links | BibTeX | Tags: Cladophora, epiphytes, succession
@article{Furey2012,
title = {Cladophora, and epiphytes: shifting interactions through succession},
author = {Paula C. Furey and Rex L. Lowe and Mary E. Power and Alexis M. Campbell-Craven},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Furey_2012_FreshSci.pdf},
doi = {10.1899/11-021.1},
year = {2012},
date = {2012-03-01},
journal = {Freshwater Science},
volume = {31},
number = {1},
pages = {93-107},
abstract = {Midge larvae (Pseudochironomus richardsoni Malloch) in the South Fork Eel River, California, weave retreats in mats of Cladophora glomerata (L.) Kütz. and graze on its algal epiphytes. Densities of these midges and their effects on Cladophora vary over time (seasonally, over the course of succession, and interannually) and space (down the drainage network). New Cladophora growth is green, turns yellow with early colonization by a monolayer of Cocconeis, and rusty-red as it becomes heavily epiphytized by a multistory layer of Epithemia spp. (Rhopalodiaceae), diatoms that contain N-fixing endosymbiotic cyanobacteria. To determine how midges influence epiphyte assemblage structure, we incubated Cladophora in early (green [G]), mid (yellow [Y]), and late (rusty-red [R]) stages of succession with and without midges and assessed changes in epiphyte density and composition. Midge effects on epiphyte composition and density (as measured by % cover on Cladophora filaments) varied with stage of succession and proximity to the ends of midge retreats. Local increases in retreat-associated cyanobacteria occurred in Y and R stages. Percent cover of Cocconeis increased on Y filaments >2 cm from midge retreats (ambient) indicating indirect midge effects (e.g., fertilization). Midges were less effective grazers on adnate Cocconeis cells than on loosely attached Epithemia and often ingested Cladophora in the process of grazing or retreat building, especially in G and Y stages. In contrast, midges that grazed on R Cladophora primarily consumed diatoms in the Rhopalodiaceae. Midge survival and retreat quality were lower in G than in Y or R stages, where retreats were longer and denser. Shifts in epiphyte composition and % cover caused by midge–algae interactions at small scales (µm–m) could affect ecologically significant processes, such as N-fixation and foodweb interactions at larger reach and watershed scales.},
keywords = {Cladophora, epiphytes, succession},
pubstate = {published},
tppubtype = {article}
}
Midge larvae (Pseudochironomus richardsoni Malloch) in the South Fork Eel River, California, weave retreats in mats of Cladophora glomerata (L.) Kütz. and graze on its algal epiphytes. Densities of these midges and their effects on Cladophora vary over time (seasonally, over the course of succession, and interannually) and space (down the drainage network). New Cladophora growth is green, turns yellow with early colonization by a monolayer of Cocconeis, and rusty-red as it becomes heavily epiphytized by a multistory layer of Epithemia spp. (Rhopalodiaceae), diatoms that contain N-fixing endosymbiotic cyanobacteria. To determine how midges influence epiphyte assemblage structure, we incubated Cladophora in early (green [G]), mid (yellow [Y]), and late (rusty-red [R]) stages of succession with and without midges and assessed changes in epiphyte density and composition. Midge effects on epiphyte composition and density (as measured by % cover on Cladophora filaments) varied with stage of succession and proximity to the ends of midge retreats. Local increases in retreat-associated cyanobacteria occurred in Y and R stages. Percent cover of Cocconeis increased on Y filaments >2 cm from midge retreats (ambient) indicating indirect midge effects (e.g., fertilization). Midges were less effective grazers on adnate Cocconeis cells than on loosely attached Epithemia and often ingested Cladophora in the process of grazing or retreat building, especially in G and Y stages. In contrast, midges that grazed on R Cladophora primarily consumed diatoms in the Rhopalodiaceae. Midge survival and retreat quality were lower in G than in Y or R stages, where retreats were longer and denser. Shifts in epiphyte composition and % cover caused by midge–algae interactions at small scales (µm–m) could affect ecologically significant processes, such as N-fixation and foodweb interactions at larger reach and watershed scales.
2001
Marks, Jane C.; Power, Mary E.
Nutrient induced changes in the species composition of epiphytes on Cladophora glomerata Kuetz. (Chlorophyta) Journal Article
In: Hydrobiologia, vol. 450, pp. 187-196, 2001.
Abstract | Links | BibTeX | Tags: Cladophora glomerata, epiphytes, nutrients, species composition
@article{Marks2001,
title = {Nutrient induced changes in the species composition of epiphytes on Cladophora glomerata Kuetz. (Chlorophyta)},
author = {Jane C. Marks and Mary E. Power},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Marks_2001_Hydrobiologia.pdf},
doi = {10.1023/A:1017596927664},
year = {2001},
date = {2001-00-00},
journal = {Hydrobiologia},
volume = {450},
pages = {187-196},
abstract = {Cladophora glomerata is a widely distributed filamentous freshwater alga that hosts a complex microalgal epiphyte assemblage.We manipulated nutrients and epiphyte abundances to access their effects on epiphyte biomass, epiphyte species composition, and C. glomerata growth. C. glomerata did not grow in response to these manipulations. Similarly, nutrient and epiphyte removal treatments did not alter epiphyte biovolume. Epiphyte species composition, however, changed dramatically with nutrient enrichment. The epiphyte assemblage on unenriched C. glomerata was dominated by Epithemia sorex and Epithemia adnata, whereas the assemblage on enriched C. glomerata was dominated by Achnanthidium minutissimum, Nitzschia palea and Synedra spp. These results indicate that nutrients strongly structure epiphyte species composition. Interactions between C. glomerata and its epiphytes were not affected by epiphyte species composition in our experiment but may be when C. glomerata is actively growing.},
keywords = {Cladophora glomerata, epiphytes, nutrients, species composition},
pubstate = {published},
tppubtype = {article}
}
Cladophora glomerata is a widely distributed filamentous freshwater alga that hosts a complex microalgal epiphyte assemblage.We manipulated nutrients and epiphyte abundances to access their effects on epiphyte biomass, epiphyte species composition, and C. glomerata growth. C. glomerata did not grow in response to these manipulations. Similarly, nutrient and epiphyte removal treatments did not alter epiphyte biovolume. Epiphyte species composition, however, changed dramatically with nutrient enrichment. The epiphyte assemblage on unenriched C. glomerata was dominated by Epithemia sorex and Epithemia adnata, whereas the assemblage on enriched C. glomerata was dominated by Achnanthidium minutissimum, Nitzschia palea and Synedra spp. These results indicate that nutrients strongly structure epiphyte species composition. Interactions between C. glomerata and its epiphytes were not affected by epiphyte species composition in our experiment but may be when C. glomerata is actively growing.
1997
Kupferberg, Sarah J.
Facilitation of periphyton production by tadpole grazing: functional differences between species Journal Article
In: Freshwater Biology, vol. 37, no. 2, pp. 427-439, 1997.
Abstract | Links | BibTeX | Tags: AQUATIC INSECTS, bottom-up, competition, epiphytes, food webs, herbivores, nutrient, stream periphyton, top-down, trophic cascades
@article{Kupferberg1997c,
title = {Facilitation of periphyton production by tadpole grazing: functional differences between species},
author = {Sarah J. Kupferberg},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/KUPFERBERG_Freshwater_Biology1997.pdf},
year = {1997},
date = {1997-04-00},
journal = {Freshwater Biology},
volume = {37},
number = {2},
pages = {427-439},
abstract = {1. This study examined how interactions between resources that vary in edibility, and herbivores that vary in ability to acquire resources, control primary productivity. In a northern California river, grazing on Cladophora glomerata, a relatively inedible filamentous green alga, and its more nutritious epiphytic diatoms, was manipulated by exposing cobbles to tadpoles (Rana boylii or Hyla regilla) or excluding tadpoles.
2. Rana indirectly facilitated Cladophora by removing diatoms, whereas Hyla did not significantly change biomass relative to controls. Algal ash-free dry mass on cobbles in Rana treatments was 65 and 72% greater than on controls in two years of investigation (1991 and 1993). Rana decreased epiphytic diatom biovolume by 56% and detritus by 87%.
3. Because nitrogen excretion rates of Hyla and Rana were similar, the differences in effect between the two species were probably due to their roles as consumers rather than as recyclers.
4. The net effect of Rana on periphyton was a 10% increase in areal specific primary productivity (mg O-2 h(-1) m(-2)); Hyla caused an 18% decrease. Rana decreased biomass-specific productivity (mg O-2 h(-1) g(-1)) 44%; Hyla had no effect.
5. In tadpole exclosures, grazers such as baetid mayfly larvae (mostly Centroptilum sp.) were 4.7 (1991) and 1.8 (1993) times more abundant, and midge larvae (Chironomidae) were 2.5 (1991) and 2 (1993) times more abundant than in Rana enclosures. Invertebrate assemblages in Hyla enclosures, however, were similar to exclosures. Few predatory insects and fish colonized Rana enclosures. Path analyses indicated that Rana affected macroinvertebrates via both interference and exploitation of epiphytic diatoms.},
keywords = {AQUATIC INSECTS, bottom-up, competition, epiphytes, food webs, herbivores, nutrient, stream periphyton, top-down, trophic cascades},
pubstate = {published},
tppubtype = {article}
}
1. This study examined how interactions between resources that vary in edibility, and herbivores that vary in ability to acquire resources, control primary productivity. In a northern California river, grazing on Cladophora glomerata, a relatively inedible filamentous green alga, and its more nutritious epiphytic diatoms, was manipulated by exposing cobbles to tadpoles (Rana boylii or Hyla regilla) or excluding tadpoles.
2. Rana indirectly facilitated Cladophora by removing diatoms, whereas Hyla did not significantly change biomass relative to controls. Algal ash-free dry mass on cobbles in Rana treatments was 65 and 72% greater than on controls in two years of investigation (1991 and 1993). Rana decreased epiphytic diatom biovolume by 56% and detritus by 87%.
3. Because nitrogen excretion rates of Hyla and Rana were similar, the differences in effect between the two species were probably due to their roles as consumers rather than as recyclers.
4. The net effect of Rana on periphyton was a 10% increase in areal specific primary productivity (mg O-2 h(-1) m(-2)); Hyla caused an 18% decrease. Rana decreased biomass-specific productivity (mg O-2 h(-1) g(-1)) 44%; Hyla had no effect.
5. In tadpole exclosures, grazers such as baetid mayfly larvae (mostly Centroptilum sp.) were 4.7 (1991) and 1.8 (1993) times more abundant, and midge larvae (Chironomidae) were 2.5 (1991) and 2 (1993) times more abundant than in Rana enclosures. Invertebrate assemblages in Hyla enclosures, however, were similar to exclosures. Few predatory insects and fish colonized Rana enclosures. Path analyses indicated that Rana affected macroinvertebrates via both interference and exploitation of epiphytic diatoms.
2. Rana indirectly facilitated Cladophora by removing diatoms, whereas Hyla did not significantly change biomass relative to controls. Algal ash-free dry mass on cobbles in Rana treatments was 65 and 72% greater than on controls in two years of investigation (1991 and 1993). Rana decreased epiphytic diatom biovolume by 56% and detritus by 87%.
3. Because nitrogen excretion rates of Hyla and Rana were similar, the differences in effect between the two species were probably due to their roles as consumers rather than as recyclers.
4. The net effect of Rana on periphyton was a 10% increase in areal specific primary productivity (mg O-2 h(-1) m(-2)); Hyla caused an 18% decrease. Rana decreased biomass-specific productivity (mg O-2 h(-1) g(-1)) 44%; Hyla had no effect.
5. In tadpole exclosures, grazers such as baetid mayfly larvae (mostly Centroptilum sp.) were 4.7 (1991) and 1.8 (1993) times more abundant, and midge larvae (Chironomidae) were 2.5 (1991) and 2 (1993) times more abundant than in Rana enclosures. Invertebrate assemblages in Hyla enclosures, however, were similar to exclosures. Few predatory insects and fish colonized Rana enclosures. Path analyses indicated that Rana affected macroinvertebrates via both interference and exploitation of epiphytic diatoms.
1995
Bergey, E. A.; Boettiger, C. A.; Resh, V. H.
Effects of water velocity on the architecture and epiphytes of Cladophora glomerata (Chlorophyta) Journal Article
In: Journal of Phycology, vol. 31, no. 2, pp. 264-271, 1995.
Abstract | Links | BibTeX | Tags: Cladophora glomerata, epiphytes, water velocity
@article{Bergey1995b,
title = {Effects of water velocity on the architecture and epiphytes of Cladophora glomerata (Chlorophyta)},
author = {E. A. Bergey and C. A. Boettiger and V. H. Resh},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Bergey_1995_JourPhyc.pdf},
doi = {10.1111/j.0022-3646.1995.00264.x},
year = {1995},
date = {1995-04-00},
journal = {Journal of Phycology},
volume = {31},
number = {2},
pages = {264-271},
abstract = {The architecture of the filamentous green alga Cladophora glomerata (L.) Kütz. and the composition of this alga's epiphytes [primarily the diatoms Epithemia turgida (Ehrenb.) Kütz., Epithemia sorex Kütz., and Cocconeis pediculus Ehrenb.] were examined in different velocity regimes. After transferring algal-bearing cobbles among velocities, the effects of changes in velocity were also examined. Cladophora branching pattern did not initially differ among slow, medium, and fast velocities, indicating that stable water velocities did not affect branching pattern. Two weeks after cobble transfer, Cladophora in fast velocity had fragmented more (i.e. had fewer filaments and fewer branch points per length of filament and had a higher percentage of unbranched filaments) than Cladophora in slow velocity. Fragmentation was greatest in tufts moved from slow velocity, suggesting velocity-associated differences in susceptibility to breakage. Epiphytic assemblage composition differed among slow, medium, and fast velocities and between locations on the filament (base and apex). Cocconeis pediculus dominated where exposure to high velocity was greater (filament apices in medium and fast velocities), whereas the Epithemia spp. dominated where lower velocities occurred (filament bases in all velocities and apices in slow velocity). Two weeks after the cobble transfer, the translocated diatom assemblages had changed and the original pattern of diatom distribution was restored.},
keywords = {Cladophora glomerata, epiphytes, water velocity},
pubstate = {published},
tppubtype = {article}
}
The architecture of the filamentous green alga Cladophora glomerata (L.) Kütz. and the composition of this alga’s epiphytes [primarily the diatoms Epithemia turgida (Ehrenb.) Kütz., Epithemia sorex Kütz., and Cocconeis pediculus Ehrenb.] were examined in different velocity regimes. After transferring algal-bearing cobbles among velocities, the effects of changes in velocity were also examined. Cladophora branching pattern did not initially differ among slow, medium, and fast velocities, indicating that stable water velocities did not affect branching pattern. Two weeks after cobble transfer, Cladophora in fast velocity had fragmented more (i.e. had fewer filaments and fewer branch points per length of filament and had a higher percentage of unbranched filaments) than Cladophora in slow velocity. Fragmentation was greatest in tufts moved from slow velocity, suggesting velocity-associated differences in susceptibility to breakage. Epiphytic assemblage composition differed among slow, medium, and fast velocities and between locations on the filament (base and apex). Cocconeis pediculus dominated where exposure to high velocity was greater (filament apices in medium and fast velocities), whereas the Epithemia spp. dominated where lower velocities occurred (filament bases in all velocities and apices in slow velocity). Two weeks after the cobble transfer, the translocated diatom assemblages had changed and the original pattern of diatom distribution was restored.