The impact of Hurricane Ivan on the primary productivity and metabolism of marsh tidal creeks in the NorthCentral Gulf of Mexico

Abstract

Past research has examined hurricane impacts on marine communities such as seagrass beds, coral reefs, and mangroves, but studies on how hurricanes affect marsh tidal creeks are lacking despite the important ecological roles that marsh tidal creeks have in coastal ecosystems. Here we report on the impact of Hurricane Ivan, which made landfall on September 16, 2004, on the primary productivity and metabolism of six marsh tidal creeks in the NorthCentral Gulf of Mexico. The hurricane did not seem to have any large, lasting impact on nutrient concentrations, primary productivity, metabolism, and chlorophyll a concentration in the watercolumn of the marsh tidal creeks. In contrast, the hurricane seemed to largely decrease gross primary productivity, net productivity, and chlorophyll a concentration in the sediment of the marsh tidal creeks. The results observed for Hurricane Ivan were coincident with those observed for four other major storms that made landfall close to the study area during 2005, Tropical Storm Arlene and Hurricanes Cindy, Dennis, and Katrina. However, the apparent negative impact of major storms on the sediment of the marsh tidal creeks did not seem to be long-lived and appeared to be dissipated within a few weeks or months after landfall. This suggests that marsh tidal creeks mostly covered with bare sediment are less disturbed by hurricanes than other types of marine communities populated with bottom-attached and/or more rigid organisms, such as seagrass meadows, coral reefs, and mangroves, where hurricane impacts can be larger and last longer.

Effects of grazing and fertilization on epiphyte growth dynamics under moderately eutrophic conditions: implications for grazing rate estimates

“…Interestingly, nutrient enrichment never increased epiphyte biomass when grazers were absent, which contrasts with results from previous experiments (Neckles et al 1993, Williams & Ruckelshaus 1993, Peterson et al 2007. The lack of a major consistent impact of nutrient enrichment on epiphyte biomass in our trials could be due to the background eutrophic conditions in our mesocosms and in the seagrass beds where the samples were collected (Cebrian et al 2008, Anton et al 2009, Plutchak et al 2010. Consistent with these naturally eutrophic levels, the levels of epiphyte biomass in the samples incubated in the mesocosms were high in comparison with values reported in the literature (Borum 1987, Neckles et al 1993, Cebrian et al 1999, Hauxwell et al 2001, Stutes et al 2007, Jaschinski & Sommer 2010, even when those levels were reduced under the presence of grazers.…”

“…The water used to fill up the aquaria was moderately eutrophic, similar to the water at the seagrass bed from which the samples were obtained. Work carried out in 2005 (Table 2; for more details, see Cebrian et al 2008, Anton et al 2009, 2011, Plutchak et al 2010 showed substantial overlap in seawater concentrations of dissolved inorganic nitrogen (DIN) and phosphate (DIP) between the seagrass bed and the site where the mesocosm water was collected, although mean values were slightly higher at the mesocosm water collection site.…”

Quantifying photosynthetic rates of microphytobenthos using the triple isotope composition of dissolved oxygen

“…Furthermore, there has been some debate as to whether radiocarbon-based productivity estimates are actually measuring gross or net productivity or something in between (e.g., Dring and Jewson 1982). Oxygen fluxes from incubations of cores in light and dark conditions in labo-ratories (Hopkinson et al 1999;Risgaard-Petersen 2003;Sundbäck et al 1991), in benthic flux chambers (Cebrian et al 2008;Jahnke et al 2000;Jahnke et al 2008), or from eddy correlation technique (Berg et al 2003;Glud et al 2010;Lorrai et al 2010;McGinnis et al 2008) are also used to estimate gross and net productivity. However these approaches require the assumption that light and dark respiration are similar, when in fact MPB light respiration appears to be greater than dark respiration by a factor of 1.5 to 2.5 (Epping and Jorgensen 1996;Fenchel and Glud 2000).…”

Coastal Habitats of the Gulf of Mexico

“…Hurricane damage to seagrass beds can be highly variable and depends on location as well as hurricane characteristics Courtemanche et al 1999;Paerl et al 2001;Coles and Brown 2007;Cebrián et al 2008;Anton et al 2009). Hurricanes have been observed to cause widespread damage to seagrasses, but also to pass with little or no damage (Poiner et al 1989;Hemminga and Duarte 2000).…”