Growth and physiological responses of three seagrass species to elevated sediment nutrients in Moreton Bay, Australia

doi:10.1016/S0022-0981(97)00060-9

Journal of Experimental Marine Biology and Ecology

Volume 217, Issue 2, 1 October 1997, Pages 253-277

https://doi.org/10.1016/S0022-0981(97)00060-9 Get rights and content

Abstract

Seagrasses, marine angiosperms with high rates of primary productivity, are often limited by the supply of nutrients, particularly nitrogen (N) and phosphorus (P). We investigated growth and physiological responses of three seagrass species (Halodule uninervis (Forsk.), Zostera capricorni Aschers and Cymodocea serrulata (r.Br.) Aschers) to elevated sediment N (100 × control) and/or P (10 × control) in adjacent monospecific beds over a 3 month period from spring to early summer. Each species exhibited different growth and biomass responses to both N and P additions. Halodule uninervis growth and biomass increased in response to N and N + P additions, indicative of exclusive N limitation of growth. In contrast, growth and biomass of Z. capricorni increased in response to N + P additions only, indicative of balanced N and P limitation. Cymodocea serrulata growth and biomass were not affected by any of the nutrient additions. Physiological characteristics (amino acid composition, tissue nutrient content, δ ¹⁵N) of all three seagrass species responded to N additions (+ N and N + P). Total amino acid content of seagrass leaves increased by 2 to 4 fold in N additions compared with controls. Concentrations of the N-rich amino acids, glutamine and asparagine, increased by 10–1000 fold in N additions, suggesting that these amino acids may be a metabolic storage for N. Tissue N content of leaves. roots and rhizomes increased and δ ¹⁵N of the leaves decreased in response to N additions. Although seagrass growth and biomass responses to nutrient additions were species specific, metabolic responses were similar for all species. This suggests physiological characteristics of seagrasses are useful for identifying saturating nutrient supply to an environment, but should not be used to determine whether nutrient availability is limiting the seagrass growth rate.

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Growth and physiological responses of three seagrass species to elevated sediment nutrients in Moreton Bay, Australia

Abstract

J. Exp. Mar. Biol. Ecol.

Aquatic Botany

J. Exp. Mar. Biol. Ecol.

J. Exp. Mar. Biol. Ecol.

Aquat. Bot.

J. Exp. Mar. Biol. Ecol.

Aquat. Bot.

J. Exp. Mar. Biol. Ecol.

Alaska. Aquat. Bot.

Aquat. Bot.

Light, nutrient and water quality interactions with the seagrass, Zostera capricorni Aschers

Seagrass depth range and water quality in southern Moreton Bay. Queensland, Australia

Mar. Freshwater Res.

Growth of the seagrass Hererozostera tasmanica limited by nitrogen in Port Philip Bay. Australia

Mar. Ecol. Prog. Ser.

Woelkerling, Effects of in situ nitrogen and phosphorus enrichment of the sediments on the seagrass Heterozostera tasmanica (Martens ex Aschers.) den Hartog in Western Port. Victoria, Australia

J. Exp. Mar. Biol. Ecol.

Rhizome/root production

Sediment ammonium availability and eelgrass (Zostera marina) growth

Mar. Biol.

Amino acid pools in nutrient limited Cyanidium calarium and responses to resupply

Phytochemistry

A comparison of methods for assessment of nutrient deficiency of phytoplankton in a large oligotrophic lake

Can. J. Fish. Aquat. Sci.

Seagrass nutrient content

Mar. Ecol. Prog. Ser.

Evidance of iron deficiency in seagrass growing above carbonate sediments

Limnol. Oceanogr.

The role of nitrogen and phosphorus in Chesapeake Bay anoxia

Use of intracellular amino acid analysis as an indicator of the physiological status of natural dinoflagellate populations

Mar. Ecol. Prog. Ser.

The effects of long-term manipulation of nutrient supply on competition between the seagrass Thalassia testudium and Halodule wrightii Florida Bay

Oikos

Phosphorus limitation of primary production in Florida Bay: Evidance from C:N:P ratios of the dominant seagrass Thalassia testudinium

Limnol. Oceanogr.