Marine Biology Commons^™

Detecting Submarine Groundwater Discharge With Synoptic Surveys Of Sediment Resistivity, Radium, And Salinity, John A. Breier, Crystaline F. Breier, Henrietta Edmonds

School of Earth, Environmental, & Marine Sciences Faculty Publications

A synoptic geophysical and geochemical survey was used to investigate the occurrence and spatial distribution of submarine discharges of water to upper Nueces Bay, Texas. The 17 km survey incorporated continuous resistivity profiling; measurements of surface water salinity, temperature, and dissolved oxygen; and point measurements of dissolved Ra isotopes. The survey revealed areas of interleaving, vertical fingers of high and low conductivity extending up through 7 m of bay bottom sediments into the surface water, located within 100 m of surface salinity and dissolved Ra maxima along with peaks in water temperature and lows in dissolved oxygen. These results indicate …

Potential Of Modis Evi And Surface Temperature For Directly Estimating Per-Pixel Ecosystem C Fluxes, Abdullah Rahman, Daniel A. Sims, Vicente D. Cordova, Bassil Z. El-Masri

School of Earth, Environmental, & Marine Sciences Faculty Publications

We tested the potential of estimating per-pixel gross primary production (GPP) directly from the MODIS enhanced vegetation index (EVI) and respiration directly from MODIS surface temperature (MOD11). Carbon flux data were obtained from 10 eddy covariance tower sites representing a wide range of North American vegetations. The correlation between across-site tower GPP and EVI was comparable (r = 0.77) to that between tower GPP and MOD17-GPP (r = 0.73), suggesting that EVI could be used to provide reasonably accurate direct estimates of GPP on a truly per-pixel basis. There was also a strong relationship (r2 = 0.67) between respiration and …

Oceanographic Conditions And Diversity Of Sea Stars (Echinodermata: Asteroidea) In The Gulf Of California, México, Carlos E. Cintra-Buenrostro, Hector Reyes-Bonilla, Maria Dinorah Herrero-Perezrul

School of Earth, Environmental, & Marine Sciences Faculty Publications

Species richness is one of the best indicators of biodiversity. However, there are few investigations on concordance of diversity patterns and environmental settings for marine regions. The objectives of this study were to correlate species richness of shallow water (< 200 m deep) sea stars with key oceanographic factors in the Gulf of California, México, and to predict species richness of Asteroidea using multiple regressions. In these analyses the Gulf was divided into nine sections of one degree in latitude (from 23 - 31° N), at each section we recorded: continental shelf area (at 100 and 200 m depth), temperature mean and range at three depth levels (0, 60 and 120 m), thermocline depth, surface nutrient concentrations (nitrates, phosphates and silicates), surface photosynthetic pigment concentration, and integrated productivity. Sea star species richness at each latitudinal section was estimated from literature data, new collections and museum records. Species were assigned to one of the following feeding guilds: predators of small mobile invertebrates (I), detritivores (D), predators of colonial organisms (C), generalist carnivores (G), and planktivores (P). There are 47 shallow water asteroid species in the Gulf of California (16 I, 15 D, eight C, six G, one P and one not assigned). Total species richness and guild species richness showed strong latitudinal attenuation patterns and were higher in the southernmost Gulf, an area characterized by a narrow shelf, high temperature, and low nutrient concentrations. Species diversity for each guild was correlated to a set of oceanographic parameters: temperature, nitrate concentration, and integrated productivity were linked to richness in must cases. We detected that nutrients and surface pigments always presented negative relationships with species richness, indicating that productive environments limit asteroid diversity in the study area. Finally, the postulated regression models to estimate species richness from oceanographic data were significant and highly precise. We conclude that species richness of Asteroidea in the Gulf of California is related to oceanographic conditions and can be estimated from regional oceanographic information.

Tracking The Sea-Level Signature Of The 8.2 Ka Cooling Event: New Constraints From The Mississippi Delta, Torbjörn E. Törnqvist, Scott J. Bick, Juan L. Gonzalez, Klaas Van Der Borg, Arie F. M. De Jong

School of Earth, Environmental, & Marine Sciences Faculty Publications

The ever increasing need for accurate predictions of global environmental change under greenhouse conditions has sparked immense interest in an abrupt, century‐scale cooling around 8200 years ago, with a focal point in the North Atlantic and with hemispheric teleconnections. Despite considerable progress in the unraveling of this striking feature, including a conceivable driving mechanism (rapid drainage of proglacial Lake Agassiz/Ojibway and a resulting reduced strength of North Atlantic thermohaline circulation), several key questions remain unanswered. One salient aspect concerns the total amount of freshwater released during this catastrophic event, likely echoed by a near‐instantaneous eustatic sea‐level rise. So far, no …

Potential Of Modis Ocean Bands For Estimating Co2 Flux From Terrestrial Vegetation: A Novel Approach, Abdullah Rahman, Vicente D. Cordova, John A. Gamon, Hans Peter Schmid, Daniel A. Sims

School of Earth, Environmental, & Marine Sciences Faculty Publications

A physiologically-driven spectral index using two ocean-color bands of MODIS satellite sensor showed great potential to track seasonally changing photosynthetic light use efficiency (LUE) and stress-induced reduction in net primary productivity (NPP) of terrestrial vegetation. Based on these findings, we developed a simple ‘‘continuous field’’ model solely based on remotely sensed spectral data that could explain 88% of variability in flux-tower based daily NPP. For the first time, such a procedure is successfully tested at landscape level using satellite imagery. These findings highlight the unexplored potential of narrow-band satellite sensors to improve estimates of spatial and temporal distribution in terrestrial …

Factors Controlling Seagrass Revegetation Onto Dredged Material Deposits: A Case Study In Lower Laguna Madre, Texas, James E. Kaldy, Kenneth H. Dunton, Joseph L. Kowalski, Kun-Seop Lee

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Our objective was to evaluate the influence of water quality and sediment chemistry on the survival and growth of Halodule wrightii transplanted onto unconsolidated dredged materials in Lower Laguna Madre, TX. Subsequent to transplanting activities, we measured environmental conditions and seagrass parameters at transplant and natural beds over a 1-yr period. Although water quality characteristics at the transplant and comparison sites were compatible with seagrass growth, transplants failed to survive for more than a few months. Seagrasses at natural sites received high light (>6000 mols m−2 y−1) and exhibited typical patterns of annual growth, biomass and density as well …

Range Extensions Of The Seaweeds Codium Taylorii And Caulerpa Prolifera Into The Lower Laguna Madre, Texas, Hudson R. Deyoe, Donald L. Hockaday

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Between January 1999 and April 2000 two chlorophyte algae, Codium taylorii Silva and Caulerpa prolifera F. obovata (Forsskal) Lamouroux were found in the lower Laguna Madre (LLM). Both are coenocytic algae and are members of the chlorophyte class Bryopsidophyceae ( van den Hoek et al. 1995). The species descriptions in Taylor (1960) were used in the identification of the specimens. Her barium specimens have been deposited at the University of Texas- Pan American Coastal Studies Laboratory (accession numbers COlO - C. prolifera, COl 1 - C. taylorii) , University of California at Berkeley (UC 1753606 - C. taylorii) , University …

Supplemental Carbon Dioxide And Light Improved Tomato And Pepper Seedling Growth And Yield, Alejandro Fierro, Nicolas Tremblay, André Gosselin

School of Earth, Environmental, & Marine Sciences Faculty Publications

The experiment was conducted to determine the effects of CO, enrichment (900 μl·liter-1, 8 hours/day) in combination with supplementary lighting of 100 μmol·s-1·m-2 (16- h photoperiod) on tomato (Lycopersicon esculentum Mill.) and sweet pepper (Capsicum annuum L.) seedling growth in the greenhouse and subsequent yield in the field. Enrichment with CO2 and supplementary lighting for » 3 weeks before transplanting increased accumulation of dry matter in shoots by » 50% compared with the control, while root dry weight increased 49% for tomato and 6270 for pepper. Early yields increased by =1570 and 11% for tomato and pepper, respectively.

Seasonal Periodicity Of Dominant, Benthic, Marine Macroalgae Of The North Jetty Of Brazos Santiago Pass, Texas, As Related To Environmental Factors, Gary J. Penn

Theses and Dissertations - UTB/UTPA

The seasonality of marine algae may be influenced by a large number of factors. These factors Include water clarity, water temperature, dissolved oxygen, conductivity, salinity, light Intensity, precipitation, air temperature, water turbulence, and daylength. The purpose of this study was to determine seasonal patterns and the effect of these variables on the algae.

The results Indicate that 24 dominant, benthic, genera of algae have two seasonal populations. A winter-spring population Includes algae in abundance between January and May. A fall population includes algae in abundance during September, October and November, Results of environmental studies indicate day-length dominant factors in algal …