The ecology of Tijuana Estuary, The ecology of Tijuana Estuary, California : a national estuarine research reserve ecologyoftijuana00zedl Year: 1992 37-46 ppt, and upper, 59-84 ppt over the one-year experiment. Overall, pickleweed grew better than in the nearby intertidal salt marsh, with biomass averaging over kg/m2 in the upper rows by late summer. In contrast, cordgrass biomass was lower than in the tidal salt marsh, with maximum values well under 1 kg/m2. Griswold's (1988) findings support the observation that pickleweed can thrive in semitidal wetlands within the region (and in the s
The ecology of Tijuana Estuary, The ecology of Tijuana Estuary, California : a national estuarine research reserve ecologyoftijuana00zedl Year: 1992 37-46 ppt, and upper, 59-84 ppt over the one-year experiment. Overall, pickleweed grew better than in the nearby intertidal salt marsh, with biomass averaging over kg/m2 in the upper rows by late summer. In contrast, cordgrass biomass was lower than in the tidal salt marsh, with maximum values well under 1 kg/m2. Griswold's (1988) findings support the observation that pickleweed can thrive in semitidal wetlands within the region (and in the southern arm of Tijuana Estuary), while cordgrass is restricted to fully tidal situations (and the northern arm of Tijuana Estuary). Although the mesocosms did not mimic the tidal hydrology of Tijuana Estuary, the relative growth of each species provides a test of their hypothesized differential inundation tolerance. DUUU ' g/m2 4000 - Pickleweed 3000 - 2000 - : 1000 - s 0 - â '''tfl'''*-' o T3 a. a. Cordgrass aboveground biomass decreased with elevation, in relation to the gradient of inundation and soil moisture (Figure ). The pickleweed response was the opposite; biomass increased as surface soil moisture declined (Figure ). Manipulation of a Competitor in a Field Experiment In order to test the hypothesis that pickleweed outcompetes cordgrass, Griswold (1988) set up a field experiment at Tijuana Estuary. Pickleweed was removed from replicate plots of mixed pickleweed-cordgrass vegetation. Griswold then compared the growth of cordgrass with that in control plots. The experiment was established in January 1987, and responses were documented monthly through October. By June, plots with pickleweed removed had significantly more stems of cordgrass present, supporting the hypothesis of competitive exclusion. By October, cordgrass had increased 6 times as fast in plots without pickleweed present. Average densities were 120/m2 ( ) without pickleweed and 36/m2
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