Spectral reflectance of the seagrasses: Thalassia testudinum, Halodule wrightii, Syringodium filiforme and five marine algae

ABSTRACT Preliminary experiments, using the subtropical/tropical coastal and estuarine seagrasses Thalassia testudinum, Halodule wrightii, and Syringodium filiforme, were carried out to examine the effects of dispersants. Experiments exposed seagrasses in vitro to concentrations of Louisiana crude oil ranging from 7.5 to 500 milliliters (mL) in 105 mL seawater at exposure times of 5 to 100 hours (seagrass not in contact with oil slick). In other experiments, the seagrasses were exposed to the dispersant Corexit 9527, which was combined with the oil in a ratio of 1 part dispersant to 10 parts oil with dispersant concentrations ranging from 0.75 to 50 mL in 105 mL seawater (dispersant plus oil forming a cloud of the substance in contact with seagrasses). The oil or oil with dispersant treatment was removed from the seagrasses after the designated exposure periods. Thereafter, the seagrasses were monitored for 14 days. Blade length was measured as a factor of growth. Thalassia showed the greatest tolerance to dispersant plus oil of the three species tested. It was not substantially affected by any oil concentration alone; however, when exposed to oil and dispersant, growth significantly decreased with concentrations of 125 mL oil and 12.5 mL dispersant in 105 mL seawater at longer periods of exposure (100 hours), and also at much decreased exposure times (5 hours) for 500 mL oil and 50 mL dispersant in 105 mL sea water. Syringodium and Halodule were generally less tolerant than Thalassia, particularly to oil. For example, at 75 mL oil/105 mL sea water and an exposure of 100 hours, growth decreased significantly and mortality increased to 53 percent. Growth and mortality of Syringodium and Halodule were further affected by the addition of dispersant.

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Assessment of Seagrass Plant Demography Within and Among Beds of Turtle Grass (Thalassia testudinum), Manatee Grass (Syringodium filiforme), and Shoal Grass (Halodule wrightii) From the Northern Gulf of Mexico

Gulf of Mexico Science ◽

10.18785/goms.2002.06 ◽

2002 ◽

Vol 20 (2) ◽

Author(s):

Paul A.X. Bologna ◽

Doug Haywick

Keyword(s):

Gulf Of Mexico ◽

Thalassia Testudinum ◽

Halodule Wrightii ◽

Plant Demography ◽

Northern Gulf Of Mexico ◽

Syringodium Filiforme ◽

Turtle Grass

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Light Requirements of Seagrasses Halodule wrightii and Syringodium filiforme Derived from the Relationship between Diffuse Light Attenuation and Maximum Depth Distribution

Estuaries ◽

10.2307/1352533 ◽

1996 ◽

Vol 19 (3) ◽

pp. 740 ◽

Cited By ~ 77

Author(s):

W. Judson Kenworthy ◽

Mark S. Fonseca

Keyword(s):

Depth Distribution ◽

Light Attenuation ◽

Maximum Depth ◽

Diffuse Light ◽

Halodule Wrightii ◽

Syringodium Filiforme ◽

Light Requirements ◽

The Relationship

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Corollospora gracilis. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20093355596 ◽

2009 ◽

Author(s):

D. I. Enríquez

Keyword(s):

South Africa ◽

New Zealand ◽

Dominican Republic ◽

Geographical Distribution ◽

Tamil Nadu ◽

Host Plants ◽

West Bengal ◽

Rhizophora Mangle ◽

Thalassia Testudinum ◽

Syringodium Filiforme

Abstract A description is provided for Corollospora gracilis. Information on the host plants (Coccoloba uvifera, Rhizophora mangle, Sargassum sp., Syringodium filiforme and Thalassia testudinum), geographical distribution (South Africa, Mexico, Japan, Thailand, Australia, New Zealand, Cuba, Dominican Republic, and Tamil Nadu and West Bengal, India), and dispersal and transmission of the pathogen is presented.

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The Effects of in Situ Light Reduction on the Growth of Two Subtropical Seagrasses, Thalassia testudinum and Halodule wrightii

Estuaries ◽

10.2307/1352324 ◽

1995 ◽

Vol 18 (2) ◽

pp. 418 ◽

Cited By ~ 56

Author(s):

Andrew B. Czerny ◽

Kenneth H. Dunton

Keyword(s):

Thalassia Testudinum ◽

Halodule Wrightii ◽

Light Reduction

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Elementos de la dieta del manatí Trichechus manatus manatus en tres sitios importantes para la especie en México y Belice

Revista Ciencias Marinas y Costeras ◽

10.15359/revmar.5.2 ◽

2013 ◽

Vol 5 ◽

pp. 25 ◽

Cited By ~ 3

Author(s):

Lavinia Flores-Cascante ◽

Benjamín Morales-Vela ◽

Nataly Castelblanco-Martínez ◽

Janneth Padilla-Saldívar ◽

Nicole Auil

Keyword(s):

Health Assessment ◽

Rhizophora Mangle ◽

Thalassia Testudinum ◽

Quintana Roo ◽

Systematic Sampling ◽

Halodule Wrightii ◽

Trichechus Manatus ◽

Herbivorous Mammals ◽

Microhistological Analysis ◽

First Time

Los manatíes (Trichechus manatus manatus) son mamíferos herbívoros y de hábitos oportunistas, se alimentan de casi 60 especies de plantas. El objetivo de este trabajo fue identificar los elementos de la dieta del manatí por medio de análisis de heces en dos sitios en México (Jonuta, Tabasco y Bahía de la Ascensión, Quintana Roo) y uno en Belice (Southern Lagoon). Las muestras provienen de manatíes de vida libre y en cautiverio que fueron capturados temporalmente para muestreo y evaluación de su salud durante el período 2004-2006. Un total de 24 muestras fueron procesadas. La identificación de los elementos de la dieta se basó en el análisis microhistológico de las heces y la separación de los ítems para su posterior comparación con material bibliográfico y colecciones histológicas. También se revisaron las muestras para la búsqueda de invertebrados. Las especies vegetales identificadas fueron: Thalassia testudinum, Rhizophora mangle, Halodule wrightii, Ruppia sp. y Panicum sp., esta última confirmada por primera vez para México. No se encontró evidencia de invertebrados en las muestras. El orden de importancia relativa de consumo de las especies vegetales por los manatíes coincide con lo reportado para otras regiones de América. Se recomienda hacer un mayor esfuerzo de muestreo en áreas donde se desconocen los ítems alimentarios de la especie.AbstractManatees (Trichechus manatus manatus) are herbivorous mammals with opportunistic habits that feed onapproximately 60 species of plants. The focus of this paper was to identify diet elements of the manateeby fecal analysis in two sites in Mexico (Jonuta, Tabasco and Bahía de la Ascensión, Quintana Roo) andone site in Belize (Southern Lagoon). Samples were obtained from wild manatees and captive manateestemporarily captured for health assessment and sampling during 2004-2006. A total of 24 samples wereanalyzed. Diet components were assessed by microhistological analysis of feces. Items were separated andcompared with bibliography and histological collections. Samples were also analyzed to detect invertebrates.Vegetal species found included Thalassia testudinum, Rhizophora mangle, Halodule wrightii, Ruppia sp. and Panicum sp., the latter confirmed for the first time for Mexico. No evidence of invertebrates wasfound in the samples. Relative importance of vegetal species consumed by manatees coincides with thefindings reported for other areas in the Americas. Further systematic sampling efforts are needed in areaswhere manatee diet items are unknown.

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