Question

Exploring Salt Marsh Ecosystems Please answer all questions

1.) What is the difference between spring tides and neap tides in terms of relative tide heights? What regions of the marsh (high, mid, low) are inundated (flooded) with water during the respective high tides (neap vs. spring)?

2.) How does the biodiversity change in different regions of the marsh? How does the frequency and severity of disturbance to each of the regions influence the biodiversity trends you observed?

3.) What natural and human-influenced factors may affect the following water chemistry parameters, and why, specifically, do the perturbations influence the integrity/health of the marsh ecosystem?

pH:

DO2 concentrations% saturation:

Temperature:

4.) How are marsh plants adapted to survive the varying salinity, temperate and oxygen levels they experience throughout a tidal cycle,. How are plants in the high marsh adapted to tolerate the occasional flooding by salt water?

5.) Describe a few adaptations that animals have to survive the varying salinities, temperatures and oxygen levels they experience in the salt marsh.

6.) Who (what groups of organisms) are the main primary producers in estuaries? How productive, relative to other ecosystems, are salt marsh estuaries?

7.) In what ways are human activities influencing the biodiversity and productivity of estuaries, and how are these influencing the ecosystem services provided by estuaries?

8.) What do you think are the important lessons of Biosphere 2, and what do they tell us about the future of our biosphere — planet Earth?

9.) If the ever-expanding human ecological footprint results in large-scale loss of salt marshes, how likely is it that humans will be able to replace our salt marshes with technologies that perform the essential ecosystem services of our natural marsh ecosystems?

Answer 1

1. Spring tides occur twice each lunar month all year long without regard to the season. Neap tides, which also occur twice a month, happen when the sun and moon are at right angles to each other.This means that high tides are a little higher and low tides are a little lower than average.Higher marshes at sites with regular tides have variation between spring and neap tides that result in some areas being flooded every day while other, higher, areas are flooded less frequently.

2. Salt marshes play a large role in the aquatic food web and the delivery of nutrients to coastal waters.A salt marsh is a coastal ecosystem in the upper coastal intertidal zone, between land and open brackish water, which is intermittently flooded by the tides.A salt marsh is a coastal ecosystem in the upper coastal intertidal zone, between land and open brackish water, which is intermittently flooded by the tide. Several interacting factors influence salt marsh vegetation patterns, including frequency and duration of tidal flooding, salinity, substrate, surface elevation, oxygen and nutrient availability, disturbance by wrack deposition, and competition among plant species.

3.

DO2-Dissolved oxygen refers to the level of free, non-compound oxygen present in water or other liquids. Dissolved oxygen is necessary to many forms of life including fish, invertebrates, bacteria and plants. These organisms use oxygen in respiration, similar to organisms on land.Microbes such as bacteria and fungi also require dissolved oxygen. These organisms use DO to decompose organic material at the bottom of a body of water Dissolved oxygen decreases exponentially as salt levels increase

pH-is a determined value based on a defined scale, similar to temperature.it is a figure between 0 and 14 defining how acidic or basic a body of water is along a logarithmic scale.If the pH of water is too high or too low, the aquatic organisms living within it will die. pH can also affect the solubility and toxicity of chemicals and heavy metals in the water.The majority of aquatic creatures prefer a pH range of 6.5-9.0, though some can live in water with pH levels outside of this range.

Temperature-Water temperature is a physical property expressing how hot or cold water is.

water temperature should be accounted for when determining

– Metabolic rates and photosynthesis production
– Compound toxicity
– Dissolved oxygen and other dissolved gas concentrations
– Conductivity and salinity
– Oxidation reduction potential (ORP)
– pH
– Water Density

The solubility of oxygen and other gases will decrease as temperature increases.

Crude Oil Degradation -Salt marshes and mudflats are very susceptible to crude oil pollution, owing to their low-tidal energy, soft fine-grained sediments and frequent proximity to shipping lanes, oil refineries.

Oil Pollution-Salt marshes are sheltered ‘oil traps’ where oil may persist for many years. In cases where perennial plants are coated with relatively thin oil films, recovery can take place through new growth from underground stems and rootstocks. Mangrove forests are one of the most sensitive habitats to oil pollution. The trees are easily killed by crude oil, and with their death comes loss of habitat for the fish, shellfish and wildlife which depend on them

4.

Halophytes live in salt marshes and are exposed to excessive salt as well as physiological drought. The ice plant (Mesembryanthemum crystnllinuni) is a succulent that grows along sandy beaches of the California coast and is exposed to extreme salinity. These plants sequester salt (NaCl) in the cell vacuole and deposit it in a gradient along their axis, with the highest concentrations (∼ 1.0M or more) in the younger growing parts.The interaction of the tides and weather, the salinity of the coastal ocean, and the elevation of the marsh plain control salinity on a marsh or mud flat. Salinity varies within a marsh with subtle changes in surface elevation. Salinity varies within a marsh with subtle changes in surface elevation

  Most marine organisms have physiological adaptations for dealing with fluctuations in salinity.

Osmotic equilibrium is attained by transfer of water, and swelling or shrinkage of the body ensures.

5.

1.Fish can drink saltwater and eliminate the salt through their gills. Fish also use their kidneys and ion pumps, such as a sodium/potassium pump, to excrete extra salt

2 .Crocodiles living in saltwater have adapted by developing special glands in their tongues to help them excrete salt

3. change their metabolism in order to survive in the different water conditions..

4. Seabirds can drink water and the excess salt is eliminated via the nasal into the nasal cavity.

6.

. An estuary is an area where sea water mixes with fresh water. Estuaries can be found along the coast. Each day as tide rises, salt water is brought into the estuary. Fresh water comes down the rivers and creeks and mixes with the saltwater. During the dry season there may not be much fresh water flowing down the rivers. This can make the estuary very salty. Also, during the dry season water evaporates out of the estuary making it even more salty.  

There are three types of producers that live in estuaries: Macrophytes, which are large, multicellular algae also known as seaweed, and phytoplankton, which is the photosynthetic component of plankton consisting primarily of single celled bacteria.

biotic factors are the primary producers, consumers, and predators. Phytoplanktons play a major role in the estuary because they are the main producers and without them the entire ecosystem would fall apart. The zooplanktons that eat the phytoplanktons and then are subsequently eaten by grass shrimp, herring, smelt, which are then eaten by larger striped bass and lastly by predatory birds, fish, otters, seals, and humans. All of these organisms rely on each other and without one; the whole balance of the estuary would break apart.he biotic factors are the primary producers, consumers, and predators.

7.

Habitats associated with estuaries, such as salt marshes and mangrove forests, act like enormous filters.One reason that estuaries are such productive ecosystems is that the water filtering through them brings in nutrients from the surrounding watershed. A watershed, or drainage basin, is the entire land area that drains into a particular body of water, like a lake, river or estuary.Estuaries and their surrounding wetlands are also buffer zones. They stabilize shorelines and protect coastal areas, inland habitats and human communities from floods and storm surges from hurricanes.When flooding does occur, estuaries often act like huge sponges, soaking up the excess water. Estuarine habitats also protect streams, river channels and coastal shores from excessive erosion caused by wind, water and ice

8

Biosphere 2 is an American Earth system science research facility located in Oracle, Arizona. Biosphere 2 was originally meant to demonstrate the viability of closed ecological systems to support and maintain human life in outer space.

It was designed to explore the web of interactions within life systems in a structure with different areas based on various biological biomes. In addition to the several biomes and living quarters for people, there was an agricultural area and work space to study the interactions between humans, farming, technology and the rest of nature as a new kind of laboratory for the study of the global ecology. Its mission was a two-year closure experiment with a crew of eight humans .ong-term it was seen as a precursor to gain knowledge about the use of closed biospheres in space colonization. As an experimental ecological facility it allowed the study and manipulation of a mini biospheric system without harming Earth's biosphere..

9.

Saltmarshes are a major, widely distributed, intertidal habitat. They are dynamic systems, responding to changing environmental condition.. Many saltmarshes are starved of sediment because of catchment modification and coastal engineering, or exposed to erosive forces, which may be of natural origin or reflect human interference. The geographical distribution of individual saltmarsh species reflects climate, so that global climatic change will be reflected by changes in distribution and abundance of species.Vulnerable to storm surges and coastal flooding, coastal communities along the North Sea Basin sought a long-term alternative to costly and continual repairs to sea walls along their shores by implementing salt marsh restoration.Microbial research will impact the salt marsh restoration.