Inter-Research > MEPS > v458 > p89-102  
Marine Ecology Progress Series

via Mailchimp

MEPS 458:89-102 (2012)  -  DOI:

Leaf-fracture properties correlated with nutritional traits in nine Australian seagrass species: implications for susceptibility to herbivory

Carmen B. de los Santos1,*, Fernando G. Brun1, Yusuke Onoda2,3, Marion L. Cambridge4, Tjeerd J. Bouma5, Juan J. Vergara1, José Lucas Pérez-Lloréns

1Department of Biology, University of Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR), PO Box 40, 11510 Puerto Real (Cádiz), Spain
2Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
3Department of Biology, Faculty of Science, Kyushu University Hakozaki 6-10-1, Fukuoka 812-8581, Japan
4School of Plant Biology and the UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
5Netherlands Institute of Ecology (NIOO-KNAW), Centre for Estuarine and Marine Ecology, PO Box 140, 4400 AC Yerseke, The Netherlands

ABSTRACT: Seagrasses are exposed to the constant risk of structural damage due to abiotic factors, such as waves and currents, and biotic factors, e.g. herbivory. Leaf mechanical resistance is therefore essential in protecting plants from structural failure and may also have ecological consequences. For example, mechanical traits of seagrass leaves may play an important role in plant−herbivore interactions and food-preferences of herbivores in these ecosystems, as widely reported for terrestrial plants. However, little is known about leaf mechanical resistance against structural damage in seagrasses and how it varies with other traits such as their nutritional value. We analysed the correlation between fracture properties relevant to herbivory and the nutritional value of seagrass leaves, testing the general assumption that species that invest heavily in mechanical resistance (toughening of the leaves) will present low nitrogen and high carbon and fibre contents. Direct measurements of leaf traits were conducted on 9 seagrass species from south-western Australia: (1) leaf-fracture properties from shearing and tearing tests, (2) nutritional values (carbon to nitrogen ratio and fibre content) and (3) morphological and structural traits (specific leaf area and leaf thickness). Results showed that leaf-fracture properties in seagrasses were tightly correlated to their C:N ratio, which reflects their nutritional value, thus supporting the general assumption that C investment is inversely correlated to N content. This close correlation suggested that patterns of seagrass consumption may be influenced not only by the C:N ratio but also by the leaf-fracture properties. Among co-existing seagrasses, we found a continuous spectrum of mechanical and nutritional traits across species, which provides fundamental information about species assembly, herbivore behaviour and ecosystem functions.

KEY WORDS: Biomechanics · Herbivory · Nitrogen · Nutritional trait · Leaf toughness · Mechanical resistance

Full text in pdf format
Cite this article as: de los Santos CB, Brun FG, Onoda Y, Cambridge ML, Bouma TJ, Vergara JJ, Pérez-Lloréns JL (2012) Leaf-fracture properties correlated with nutritional traits in nine Australian seagrass species: implications for susceptibility to herbivory. Mar Ecol Prog Ser 458:89-102.

Export citation
Share:    Facebook - - linkedIn

 Previous article Next article