Effects of atmospheric exposure on chlorophyll <i>a</i>, biomass and productivity of the epilithon of a tailwater river

Angradi, Ted R.; Kubly, Dennis M.

doi:10.1002/rrr.3450080405

Cited by 38 publications

(23 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increasing exposure time reduced biomass of Cladophora glomerata remaining on rock surfaces after rewetting below a hydroelectric dam (Angradi and Kubly, 1993;Blinn et al, 1995). Both chlorophyll and ash-free dry mass decreased when the exposure period was extended from 1 to 3 days, as greater desiccation made cells more friable and likely to break and be lost after rewetting (Usher and Blinn, 1990).…”

Section: Algal Responses To Drying and Rewetting In Streamsmentioning

confidence: 99%

Effects of water loss on primary production: A landscape-scale model

Stanley

Fisher

Jones

2004

Aquatic Sciences - Research Across Boundaries

View full text Add to dashboard Cite

Water loss from stream ecosystems has profound effects on primary producers. The small body of literature on algal responses to desiccation has emphasized mechanisms of resistance to desiccation, recovery of metabolic activity upon rewetting, and small spatial scales. Unfortunately, small-scale patterns are difficult to interpret because of the high degree of variability in both hydrologic patterns of drying and ecological processes within individual drainage basins. Consequently, effects of drying are best examined at larger spatial scales because variation that appears random at smaller scales become incorporated into larger, more predictable patterns across an entire catchment. We present a conceptual model of the effects of water loss on primary producers applicable to the scale of the entire catchment. This Aquatic Sciencesperspective describes differences in susceptibility to water loss, and differential rates of decline and recovery in primary production as a function of location within the catchment. Future considerations of drying on ecosystem attributes such as primary production will be facilitated by treating streams as patchy, interconnected landscapes in space and time and recognizing spatially explicit effects of disturbance. It is likely that streams of different regions vary widely in terms of the occurrence of drought, the geophysical template, and response variables (types of organisms present and their collective metabolism). The challenge in drought research today is to determine what phenomena are general and of widespread application and which are peculiar to given regions.

show abstract

Section: Algal Responses To Drying and Rewetting In Streamsmentioning

confidence: 99%

Effects of water loss on primary production: A landscape-scale model

Stanley

Fisher

Jones

2004

Aquatic Sciences - Research Across Boundaries

View full text Add to dashboard Cite

show abstract

“…During dehydration, the photosynthetic process is usually blocked and therefore any further absorbed energy cannot be used in the photosynthetic pathway, resulting in photoinhibition or even photodamage (Wieners et al 2012). Thus, a decrease in Chlorophyll-a (Chl-a) and changes in pigment composition can be seen both as a consequence as well as a response to protect cells (Angradi and Kubly 1993;Fleming and Castenholz 2007).…”

Section: Introductionmentioning

confidence: 99%

Photosynthetic pigment changes and adaptations in biofilms in response to flow intermittency

et al. 2014

View full text Add to dashboard Cite

Among the environmental factors affecting benthic algae and cyanobacteria in streams, the one often producing the largest effects is flow intermittency. This study aimed to characterize the responses of algal assemblages to flow intermittency in a Mediterranean intermittent stream during the drying, non-flow (112 days), and rewetting phases. Algae growing in the epilithic, epipsammic and hyporheic streambed compartments were analyzed for pigment composition, and for the existence of structural changes in cells. Chlorophyll-a concentrations decreased between 60 to 90 % during the non-flow phase, indicating low resistance of algal assemblages to desiccation. In contrast, fast recoveries of Chlorophyll-a when flow resumed indicated high resilience. Pigment composition revealed that the epilithic algal assemblage was considerably different than the epipsammic and hyporheic ones. These differences were mainly attributed to the physical conditions prevailing on each streambed compartment that allowed the growth of different algal assemblages. During the non-flow phase, the synthesis of protective carotenoids (i.e. echinenone and scytonemin) and the occurrence of cell resistance structures (i.e. enlarged membrane thickness and resistant spores) enhanced resistance of the epilithic biofilm. The resistance observed in the epilithic biofilm might also be related to the tightly adhered growth-form of algae on this substratum. Main results suggest that algal assemblages in the epilithic compartment, which were the most exposed to desiccation, were structurally and functionally better adapted to flow interruption than those colonizing other streambed compartments, and that this compartment plays a crucial role in maintaining ecosystem functions under varying flow periods.

show abstract

“…During normal inflow years, the maximum range of daily flows exceeded 750 m 3 /s every month of the year. This large range in daily flow approximated the post-dam annual discharge range, and exposed the benthos along the shoreline to daily desiccation (Angradi and Kubly, 1993;Blinn et al, 1995). Impoundment reduced sediment transport at Lees Ferry to < 1% of pre-dam levels (Howard and Dolan, 1981), and mainstream turbidity is now largely determined by tributary-derived suspended sediment contributions.…”

Section: Study Areamentioning

confidence: 93%

“…(1) The tailwaters benthos is incrementally affected by baseflow stage, flow fluctuations and seasonal aspects of the flow regime (Usher and Blinn, 1990;Angradi and Kubly, 1993;Blinn et al, 1995). (2) Cobble-bar AFDM decreased by more than 37fold downstream from the Paria River confluence, and two-fold more past the Little Colorado River confluence, in concert with reduced water clarity.…”

Section: An Altered Benthosmentioning

confidence: 99%

Colorado river benthic ecology in Grand Canyon, Arizona, USA: dam, tributary and geomorphological influences

Stevens

Shannon

Blinn

1997

Regul. Rivers: Res. Mgmt.

142

View full text Add to dashboard Cite

The serial discontinuity concept (SDC; Ward and Stanford, in Ecology of River Systems, 1983) predicts that recovery of large regulated rivers over distance downstream from a dam is limited by relative tributary size; however, channel geomorphology may also influence the recovery process. We examined the spatial variation in water quality, benthic composition and ash‐free dry standing biomass (AFDM) among the bedrock‐defined geomorphological reaches in three turbidity segments of the Colorado River between Glen Canyon Dam and Diamond Creek, Arizona, including most of the Grand Canyon. This 387‐km long study area supported virtually no Ephemeroptera, Plecoptera or Trichoptera, probably because cold, stenothermic, hypolimnetic releases limited maximum aestival warming to 17·1°C. The benthos displayed abrupt, physically related decreases in AFDM over distance from the dam and in the varial zone. The 26‐km long clear water segment between the dam and the Paria River supported a depauperate Cladophora glomerata/epiphyte/chironomid/Gammarus lacustris/lumbricine/Physella sp. assemblage, and ooze‐dwelling oligochaetes. This segment contained 6·9% of the aquatic habitat below the 140 m3/s (normal minimum) discharge stage of the Colorado River study area, but supported 63·5% of the benthic primary producer AFDM and 87% of the benthic consumer AFDM in the entire study area. Turbidity increased and light penetration decreased immediately downstream from the confluence of the small, turbid Paria River, and further downstream from the Little Colorado River confluence. The benthos downstream from the Paria River was abruptly replaced by an Oscillatoria/Simuliium assemblage with a mean AFDM of <0·12 g C/m2. Dam‐related effects on water clarity, varial flow and water temperature overrode geomorphological influences on habitat availability. These results generally support the SDC, in that recovery of the benthos did not take place over distance in this large river ecosystem; however, geomorphological differences in substratum availability between reaches mediated dam and tributary effects on water clarity and benthic AFDM. Interactions between flow regulation and geomorphology produce a pattern of circuitous recovery of some physical river ecosystem characteristics over distance from the dam, but not of the benthos. Improving discharge management for endangered native fish populations requires detailed understanding of existing and potential benthic development, and trophic interactions, throughout the geomorphological reaches and turbidity segments in this river. © 1997 John Wiley & Sons, Ltd.

show abstract

Effects of atmospheric exposure on chlorophyll a, biomass and productivity of the epilithon of a tailwater river

Cited by 38 publications

References 16 publications

Effects of water loss on primary production: A landscape-scale model

Effects of water loss on primary production: A landscape-scale model

Photosynthetic pigment changes and adaptations in biofilms in response to flow intermittency

Colorado river benthic ecology in Grand Canyon, Arizona, USA: dam, tributary and geomorphological influences

Contact Info

Product

Resources

About