Algal biomass accrual in relation to nutrient availability and limitation along a longitudinal gradient of a karst riverine system

Penick, MD; Grubbs, SA; Meier, AJ

HERO ID

3618088

Reference Type

Journal Article

Year

2012

Language

English

HERO ID 3618088
In Press No
Year 2012
Title Algal biomass accrual in relation to nutrient availability and limitation along a longitudinal gradient of a karst riverine system
Authors Penick, MD; Grubbs, SA; Meier, AJ
Volume 4
Issue 1
Page Numbers 1-13
Abstract Nutrient availability influences growth, productivity, and community structure of primary producers. Nutrient limitation, however, results from a deficiency mainly in nitrogen (N) or phosphorus (P) levels relative to cellular growth needs. Limitation is a function of biotic and abiotic factors, the latter including land-use activities (e.g., agriculture, septic systems) and underlying bedrock features. The purpose of this study was twofold: (1) to assess the relationship between algal biomass and ambient nutrient levels along the longitudinal course of a river through a transition from weak to well-developed underlying karst bedrock and (2) experimentally assess if periphyton was N- or P-limited between weak and well-developed karst reaches. Sestonic and Cladophora biomass (=chlorophyll-a) levels increased sharply along the longitudinal gradient. Cladophora biomass, in particular, was strongly correlated with nitrate levels. In contrast, periphyton biomass (=chlorophyll-a) levels were sporadic and did not display a longitudinal pattern. With the exception of ammonia, individual nutrient levels generally increased longitudinally and were higher in the downstream karst reaches. Total N/total P ratios also increased longitudinally and were >25 throughout the study region, suggesting P limitation. The results of the nutrient limitation studies, however, coupled with high concentrations of both N and P throughout the study reach in excess of eutrophication thresholds, suggest that total nutrients are not limiting within the study region. Overall, Kentucky's upper Green River appears to be a nutrient-enriched, eutrophic system and particularly in the downstream, well-developed karst reaches.
Doi 10.1186/2008-6970-4-20
Url http://search.proquest.com/docview/1732836622?accountid=171501
Is Certified Translation No
Dupe Override No
Comments Journal: International Aquatic Research ISSN: 2008-4935
Is Public Yes
Language Text English
Keyword Algae, Nutrients, Phosphorous, Nitrogen, Nitrate, Karst, Cladophora
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