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

Estuaries ◽  
1995 ◽  
Vol 18 (2) ◽  
pp. 418 ◽  
Author(s):  
Andrew B. Czerny ◽  
Kenneth H. Dunton
Keyword(s):  
Thalassia Testudinum ◽  
Halodule Wrightii ◽  
Light Reduction

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

2013 ◽  
Vol 5 ◽  
pp. 25 ◽  
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.

scholarly journals Thalassia testudinum phosphate uptake kinetics at low in situ concentrations using a 33P radioisotope technique

2006 ◽  
Vol 51 (1) ◽  
pp. 208-217 ◽  
Author(s):  
Ole I. Nielsen ◽  
Marguerite S. Koch ◽  
Henning S. Jensen ◽  
Christopher J. Madden
Keyword(s):  
Phosphate Uptake ◽  
Thalassia Testudinum ◽  
Uptake Kinetics

scholarly journals DOWNWELLING DIFFUSE ATTENUATION COEFFICIENTS FROM IN SITU MEASUREMENTS OF DIFFERENT WATER TYPES

2014 ◽  
Vol 10 (2) ◽  
Author(s):  
Bisman Nababan ◽  
Veronica S.A. Louhenapessy ◽  
Risti E Arhatin
Keyword(s):  
Water Column ◽  
Coastal Region ◽  
Euphotic Zone ◽  
Time Range ◽  
Water Type ◽  
Attenuation Coefficients ◽  
Water Types ◽  
Light Reduction ◽  
Ocean Ecosystem

Process of light reduction or loss (attenuation) by scattering and absorption is affected bysolar zenith, time, depth, and seawater constituents. Downwelling diffuse attenuation coefficient (Kd)is important to understand for light penetration and biological processes in ocean ecosystem. It is,therefore, important to know the Kd value and its variability in ocean ecosystem. The objective of thisstudy was to determine downwelling diffuse attenuation coefficients and its variability form in situmeasurements of different water types. In situ downwelling irradiances (Ed) were measured using asubmersible marine environmental radiometer instrument (MER) during a clear sky, calm watercondition, and at the time range of 10:30 a.m. up to 14:00 p.m. local time in the northeastern Gulf ofMexico in April 2000. In general, Ed values decreases exponentially with depth. Ed at 380 nmexhibited the lowest attenuation (the most penetrative light), while Ed at 683 nm exhibited the highestattenuation (the most light loss at the top of water column). Overall, the Kd patterns tended to decreasefrom 380 nm to 490 nm (blue-green wavelength), and increase from 490 nm to 683 nm (green-redwavelength). Kd values in offshore region were relatively lower than in coastal region. Kd can be usedto determine the depth of euphotic zone in offshore or teh case-1 water type and the depth of oneoptical depth (the water column depth where the ocean color satellite can possibly sense).

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

2013 ◽  
Vol 5 ◽  
pp. 25
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.

Reproductive phenology of the subtropical seagrasses Thalassia testudinum (turtle grass) and Halodule wrightii (shoal grass) in the northwest Gulf of Mexico

2016 ◽  
Vol 59 (6) ◽  
Author(s):  
Kelly M. Darnell ◽  
Kenneth H. Dunton
Keyword(s):  
Gulf Of Mexico ◽  
Life Histories ◽  
Thalassia Testudinum ◽  
Individual Species ◽  
Reproductive Phenology ◽  
Halodule Wrightii ◽  
Complete Understanding ◽  
Successful Management ◽  
Turtle Grass ◽  
Seagrass Cover

Abstract Seagrass cover is declining worldwide, and successful management, conservation and restoration require a complete understanding of individual species’ life histories. The historically undervalued importance of sexual reproduction in seagrass population dynamics has prompted investigations of reproductive phenology and output. Here, we present the results of a multi-year study examining the reproductive phenology and output of two dominant seagrass species in the northwest Gulf of Mexico,

Sign in / Sign up

Export Citation Format

Share Document