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We will quantify the flow regime within and immediately adjacent to tree islands. Additionally, we will measure water flow rates in open marshes between tree islands, and both upstream and downstream of tree islands, focusing on how the islands themselves modify flow regimes in the landscape. We hypothesize a positive feedback mechanism whereby tree islands accelerate local water flow by channeling water around their higher elevations (he Bernoulli Effect), which leads to maximal flows along the upstream island flanks that scour sediments here but deposit them immediately downstream of the islands (in the ?tail? region). In this way, tree islands actually maintain their structure, and those not ?anchored? in place by geologic features may actually migrate downstream very gradually. If this mechanism is important, then within a given landscape, tree islands should be more abundant, more elongated, and more consistent in their directionality when peak flow rates are relatively high for a given mass flux of water. Inclusion of such peak flow rates within the annual hydrologic regime might therefore be conductive to maintaining tree islands within the wetland mosaic. Water flow is important to the open marsh as well. In addition to the well-substantiated hypothesis that flow is critical to maintenance of the [sawgrass] ridge and [deeper water] slough topography of ENP marshes, we suggest flow is also the critical force responsible for particle transport. Everglades wetlands contain very little inorganic sediment, and most particles found in these marshes are organic in nature. Furthermore, Everglades wetlands are characterized by very clear water. The bulk of particulate organic matter is these marshes takes the form of flocculent detritus (?floc?) found in an unconsolidated layer just above the soil surface. We hypothesize that 1) water flow is critical to moving this floc as bedload through Everglades marshes; 2) the minimum flow necessary to mobilize and move floc controls the importance of that floc to local ecological processes, including soil dynamics and plant productivity, and; 3) the downstream transport of floc is the most important organic matter and nutrient input to Everglades estuaries by the upstream freshwater landscape.
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