Montezuma Slough vs. Joice Island Slough

Montezuma Slough vs. Joice Island Slough

Joice Island Slough VS Montezuma SloughMarshes or Estuarine are found between open salt water of the bays and the uplands of cost. Marshes are usually protected from waves by natural sources, which helps create breeding place for species absolutely necessary for the prosperity of our food chain. Marshes can also be found by fresh water that drains into bay. Different PH levels and subtle and settled water waves make marshes different from lakes, rivers, and sea. Marsh water is usually basic due to the calcium carbonate levels.Suisun Marsh is one of the largest brackish water marshes on the west coast. The Marsh supports sensitive plant species such as the Suisun thistle, which is a Marsh endemic and found nowhere else in the world.

Dissolved oxygen, salinity levels, plant community composition, and the size of marsh, trophic gradient, all effect the biological makeup of marshes. In the Journal of Plankton Research, study conducted by Ward Appeltan in estuaries showed that “…factors such as salinity, temperature and oxygen in addition to biotic factors such as predation, competition, and food supply determines the population size of a marsh.” (Ward Appeltans, 2003). Moreover an experiment conducted, over the span of five years that sought the relationship between macrophytes , phytoplankton, and nutrient concentration, indicated that estuarine with high level of submerged macrophytes inhibit high concentrations of phytoplankton and nutrient concentration (Kyle D Zimmer, 2003). Meanwhile, another Journal of Plankton Research conducted an experiment that showed that within an estuarine, the presence of zooplankton concentration depends upon the depth of the water of an estuary (Gyung Soo Park, 2000). Sometimes the invertebrate species like small fish move to different places, as supported by Paterson experiment, because “… shallow estuarine may provide refugia for fishes vulnerable to predation.”(Paterson &Whitfield, 2000)

After analyzing all of these scientific journals, it was obvious that different amount of PH levels, dissolved oxygen levels, and tropic gradient in an estuary will yield a totally different habitats. Moreover, we related that different size of slough would have different biological makeup from each other due their difference. In our experiment we took samples of zooplanktons, chlorophyll, and water from a Montezuma Slough, medium slough, and Joice Island Slough to find out things that are common and different to their biological makeup.

This experiment was conducted at two different sites in Suisun marsh. Our first site, Montezuma slough, was located at Belden’s Landing. We collected samples here on fishing pier and boat dock. The second site was Joice Island Bridge, located less than two miles from the site. Here we collected samples when we were on the bridge and below it from Cutoff Slough.

On six October of 2004, we took our first samples from the bottom of the marsh. We used dredge to get the samples of macro zooplankton and benthic organisms. The dredge was used to collect samples from marsh bottom. The dredge was used at the fishing pier. The particular dredge we used was Petit Ponar dredge. The dredge was loaded with spring so that it could close just by few jerks of the rope, capturing the bottom soil sample, once lowered. As the dredge closed it trapped good amount of fine, thick, dark, murky silt from the marsh bottom. Markings, on the rope that was lowered down, helped us know the depth at which we took the sample. The dredge was also tied with another rope for safety reasons. We dredged our sample from two-meter depth of bottom of Montezuma slough. When we pulled up the dredge onto the pier it was opened and the sample of mud was dumped into a bucket that had 500-micron mesh bottom. After unneeded residue of pieces of glass, bottle, and bottle caps were removed from the dredge sample, the bucket was taken down to the boat dock to be rinsed. The mesh basket was rinsed when we lowered it into the slough water fourth of the way, and twisted it left to right until the water under the bucket got clear. This procedure took five to seven minutes.

We took two samples from Montezuma slough and one from Cutoff, Joice Island, and slough using the same procedure as described above. The sample collected from Montezuma was heavy fines and dark, while Cutoff sample was rocky and brown. The rocks at the bottom of Joice Island Slough gave us trouble getting a good dredge sample. After many attempts to get as much of the mud, we were successful to get one sample that was qualified to be used in the experiment. Once the sampled were rinsed at the dock, they were put inside a bottle along with formaldehyde and red dye for visibility and perseverance.

On the fishing pier a special contraption was used for collecting the chlorophyll levels, at surface and one meter deep, from the Montezuma Slough. A wine bottle was attached to the dredge with rope allowing the opening to be positioned at approximately one meter deep. Then a cork was inserted into the opening with a rope attached. The dredge was used to weigh down the wine bottle. After dropping the dredge into the water and letting it reach bottom the rope attached to the cork was pulled, by someone on the pier, so as to sample water from one meter deep. After letting the bottle fill it was removed from the slough and the water collected was poured into a 50mL graduated cylinder. The water from the cylinder was poured over a filter using the Schroeter Method of Chlorophyll Extracting with a Turner Flouorometer. This entire method was repeated at the same site to check for consistency in the chlorophyll levels at one meter deep. However, at the start the wine bottle was simply dropped into the slough and allowed to float until water flowed into the opening from the surface level. The same methods were applied while collecting chlorophyll from the Cutoff Slough; however, no samples were collected from the surface and only one sample was collected from approximately one meter deep.

Water quality was conducted, using the YSI 85 water-quality probe, at the boat dock of Montezuma Slough and beneath the Joice Island Bridge at the Cutoff Slough. Three individual groups took separate measurements and recorded the data collected from the Montezuma Slough. The readings were taken at surface, one meter deep, and three meters deep.

Graph and result tables clearly show that Montezuma had higher dissolved oxygen percentage, percent saturation, conductivity, specific conductivity, and PH levels at almost every level of depth. Specific conductivity and conductivity is higher in Joice Island slough but only at two meter surface, while it also has higher temperature. On the other hand, chlorophyll concentration, as the result table and graphs show, in Joice Island slough was three times as much as it was found in medium size, Montezuma Slough, at one meter depth.

Montezuma had three times as much concentration of macro zooplankton present than Joice Island Slough had data shows that benthic organisms like Oligochaeta was found in enormous amount in Montezuma and Codylophora lacustris and Laonome sp were three times as much in Joice Island Slough compared to Montezuma. Only one Neanthes Limnicola, Native polychaeta specie, was found in both of the marshes. In addition, one Isopoda, Corbicula luminea (Bivalvia) and two Potamacorbula amurensis (Bivalvia) were found but only in Joice Island slough.

High concentration of dissolved oxygen, PH levels, percent saturation, specific conductivity, and conductivity are the reason why Montezuma slough has three times as much macrozooplankton, Hydrozoa, and Oligochaeta species compared to Joice Island slough. On the other hand in Joice Island slough, high surface to volume ration has caused three times as much chlorophyll concentration. This confirms our hypothesis that different slough sizes have different biological makeup.

We found out that water chemistry was directly proportionalto the number of macrozooplanktons. Our data matches Ward Appeltan’s research article as he said that high dissolved oxygen in marsh water attract animal species and causes them to be more successful. He also mentioned that In the Journal of Plankton Research, experiment conducted in estuaries showed that “ spatial shift of population of Eurytemora affins( Copepoda, Calanida) from brakish water towards lower salinities in the Schelde estuary coincided with an increase oxygen concentration in freshwater zone.(Ward Appeltans, 2003). Another experiment conducted by Gregory hood proved that “the amount of organic material in channel sediment scaled negatively with channel size as did the abundance of benthic sources deposits.” (Hood, Gregory W., 2002), which means that if the amount of chlorophyll is greater in a marsh then the size of the marsh will be smaller because the organic decay is produced by dead chlorophylls. This also proves and supports our data and hypothesis.

It is also logical that if chlorophyll only grows on the surface of marsh water it will be more in small marsh compared to big one because the surface area of medium size marsh has a lot of depth and volume but small size slough has higher surface area compared to its volume and depth. Moreover it’s very well-known that oxygen is absolutely necessary for the survival, and if it is more at one marsh than the other one the species would prefer and try to get into the one with high dissolved oxygen levels. Another reason why there are more macrozooplankton and their predators is that oxygen also provide refuge to those invertebrates that are connected to the food chain of macrozooplankton.

The numbers of macrozooplankton were great in Montezuma slough it caused Maeotias inexpectas, their predators, to be successful and prosper in greater amount, and low numbers of copepods in Joice Island slough, caused predetor, Maeotias, to be less similarly. However polchaeta were more in Joice Island Slough than Montezuma.

Marsh was smelly gathered up water to me before but after I found out that it can be so unique depending upon just its size was amazing. Not only does it show that it provides safe haven for native species and some other animal and plant species, it provides a fresh water source for the birds and humans during drought seasons, and acts a big shelter that keeps those species necessary for the food chain alive. If these marshes are destroyed than they will have a big impact on our chain of survival. In fact freshwater sloughs are so good that big projects are going to build artificial slough for the good of the environment.

(Gregory W Hood, 2002 Relationships among nutrients, phytoplankton, macrophytes, and fish in prairie wetlands.), (Ward Appeltans et al, 2003 Zooplankton in the Schelde estuary (Belgium/The Netherlands). The distribution of Eurytemora affinis: effect of oxygen?), (Kyle D Zimmer Butler, Malcolm G., mark a. Hanson,, 2003 Relationships among nutreints, phytoplankton, macrophytes, and fish in prairie wetlands), (Gyung Soo Park, Marshal, Harold g. , 2000 Estuarine relationship between zooplankton community structure and trophic gradients), ( Paterson &Whitfield, 2000 Do Shallow-water Habitats Function Refugia for Juvinile Fishes?)




Marshal, Harold g., and Gyung s. Park. “Estuarine relationship between

zooplankton community structure and trophic gradients.” Journal of Plankton

Research (2000). 05 Nov. 2004



Appeltans, Ward , et al. “Zooplankton in the Schelde estuary (Belgium/The

Netherlands). The distribution of Eurytemora affinis: effect of oxygen?”

Journal of Plankton Research (2003). 05 Nov. 2004



Kantrudi, Harold a., and Robert E. Stewart. “Vegetation of Prairie Potholes,

North Dakota, in Relation to Quality of Water and Other Environmental Factors.”

Geological Survey Professional Paper 585-D (1972). 05 Nov. 2004



Butler, Malcolm G., mark a. Hanson, and Kyle D. Zimmer. “Relationships among

nutreints, phytoplankton, macrophytes, and fish in prairie wetlands .”

Canadian Journal of Fisheries and Aquatic Sciences (2003). 05 Nov. 2004



Hood, Gregory W. “Relationships among nutreints, phytoplankton, macrophytes,

and fish in prairie wetlands .” Canadian Journal of Fisheries and Aquatic

Sciences (2002). 05 Nov. 2004


6)Paterson, A W., and A K. Whitfield. “Do Shallow-water Habitats Function Refugiafor Juvinile Fishes?” Estuarine, Coastal and Shelf Science (2000).

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