The Ecosystems in estuaries and sea coasts systems

Table of Contents

1. Introduction

2. Material and Method

3. Results
3.1 Fauna from Torry Burn, South Alloa, Kincardine and S Queensferry
3.2 Abundance, biomass and productivity of mean species from Torry
Bay, South Alloa, Kincardine and S Queensferry
3.3 Arenicola marina casts from Torry Bay
3.4 Physical data of sediment in Torry Bay
3.4 Flora

4. Discussion
4.1 Fauna from Torry Burn, South Alloa, Kincardine and S Queensferry
4.2 Abundance, biomass and productivity of mean species from Torry Bay, South Alloa, Kincardine and S Queensferry
4.3 Arenicola marina casts from Torry Bay
4.4 Physical data of sediment in Torry Bay
4.4 Flora

6. Conclusion

7. References

1. Introduction

The students from the Department of Biology Sciences (Marine Biology course) undertook an excursion to the Forth Estuary "Torry Bay" on 08th March, 2004. The students collected different samples from three investigation locations (Sandier flats, Mud flats and Torry Burn). On 22nd March, 2004 the collected samples of the excursion were examined at the laboratory of the University of Stirling.

Samples were collected by the water surface “puddles”, sediment water and sediment cores for later examinations in lab. The salinity was determined by the water surface and by the sediment water sample in place. In addition lugworm casts counted in square (1 m x 1m). The collected samples were analyzed in the lab; two weeks later about to estimate the ecosystem in estuaries and sea coasts, i.e. which roll they play in the flow of energy through the ecosystem and to determine in outline the distribution of organisms in relation to the environmental features. At last the GPS data was recorded to hold the geographical location were the samples were taken.

The area under investigation “The Firth of Forth” is located on the east coast of central Scotland. It is a complex estuarine site, stretching for over 100 km from the River Forth at Stirling eastwards past Edinburgh and along the coasts of Fife and East Lothian to a wide estuary mouth. A wide range of coastal and intertidal habitats is found within the site. Extensive mud-flats occur particularly in the Inner Firth, notably at Kinneil Kerse and Skinflats on the south shore and Torry Bay on the north shore. Typically, the flats support a rich invertebrate fauna, with Eelgrass Zostera spp. growing on the main mud-flats, both features providing important food sources for the large numbers of migrating and wintering water birds that depend on the estuary. The Firth is of major importance for a rich assemblage of water birds in the migration periods and through the winter.^[1]

2. Material and Method

Field work (Torry Bay):

At the location all students were divided into three groups. The first group examined the range "Sandier flats (higher up the shore)"; the second group the range "Mud flat (lower shore)" and the third group the range "Torry Burn (lower shore with freshwater input)". In place, these three large groups were divided again into smaller groups to share the field work. Our reduced group consisted five persons and belonged to the Sandier flats group.

The materials to collect the samples and for the salinity to examined were used as described in the script.

Our group took four samples, beyond the Zostera zone, of the water surface, four samples of sediment water and four of sediment core and the instructions were obeyed as described in the script. The count of lugworm casts was obeyed as described in the script, as well. But the 1m x 1m square was thrown by random. In place the GPS data was taken where our group collected the samples. At the end salinity was examined by water surface and sediment water.

Lab work:

The materials to examine the samples were used, as described in the script. For very small samples we used the microscope and pair of tweezers, as well.

The instructions were obeyed, as described in the script. The students worked in the same groups as on the excursion "Torry Bay", but only two of these students could work together at the laboratory. Subsequently, all results of the groups were registered on an MS Excel spreadsheet to make sure that the results are available to all students.

To calculate the abundance of fauna, biomass and productivity the following formulas were used. All values for the equation are available in the script and in appendix A.

Equation for the abundance (m-2) of fauna:

No. of organisms / No. of Cores taken = No. of organisms (1 core taken)

No. of organisms (1 core taken) / 0.0045 m-2 = No. of organisms m-2 (abundance m-2)

Equation for the biomass (gm-2­) of fauna:

No. of organisms / No. of Cores taken = No. of organisms (1 core taken)

No. of organisms (1 core taken) x Individual approx. mean dry tissue wt. (mg) = No. of organisms mg dry wt.

(biomass mg)

No. of organisms mg dry wt. / 10000 = No. of organisms g dry wt. (biomass g)

No. of organisms g dry wt. / 0.0045 m-2 = No. of organisms g dry wt. m-2 (biomass gm-2)

Equation for the productivity (gm-2­ y-1) of fauna:

No. of organisms g dry wt. m-2 x Approx. annual P/B ratio = annual production of organisms gm-2y-1

3. Results

3.1 Fauna from Torry Burn, South Alloa, Kincardine and S Queensferry

In Torry Bay were found different taxa from Torry Burn, Torry Bay Mud and Torry Bay Sand, as follows:

In Torry Burn were taken 8 samples with a core (0.0045 m-2) and founded Macoma balthica, Cerastoderma edule, Hydrobia ulvae, Nereis diversicolor, Arenicola marina, Corophium volutator, Glycera alba, Spionidae sp ., Polydora sp ., Nephtys caeca, Oligochaeta spp . and Polychaeta spp ..

The visible distribution shows us a lot of Macoma balthica (31), Corophium volutator (33), in the middle Oligochaeta spp . (21), Arenicola marina (12), Hydrobia ulvae (11) and less Cerastoderma edule (2), Glycera alba (2) and Nephtys caeca (1). In all were founded 13 Taxa and therfrom 147 individuals.

In Torry Bay Mud (Mud flats) were taken 9 samples with a core (0.0045 m-2) and founded Macoma balthica, Cerastoderma edule, Hydrobia ulvae, Nereis hombergi, Arenicola marina, Corophium volutator, Spionidae sp ., Polydora sp ., Nephtys caeca, Nereis pelagica,

Scalibregma inflatum, Cirratulida spp ., Priapus caudatus, Polychaeta spp ., Ophelia sp ., Paraonida sp . and Chaetozone sp ..

In this case the visible distributions shows us a lot of Corophium volutator (82), in the middle Macoma balthica (25), Cirratulida spp. (14) and less Cerastoderma edule (2), Nephtys caeca (2), Chaetozone sp. (2), Scalibregma inflatatum (1), Nereis hombergi (1), Priapus caudatus (1), Ophelia sp. (1) and Paraonida sp . (1 ). In all were founded 17 Taxa and therfrom 160 individuals.

In Torry Bay Sand (Sandier flats) were taken 8 samples with a core (0.0045 m-2) and founded Macoma balthica, Cerastoderma edule, Hydrobia ulvae, Nereis diversicolo, Nereis hombergi, Arenicola marina, Spionidae sp ., Polydora sp ., Scalibregma inflatum, Cirratulida spp ., Sarachalidae sp ., Polychaeta spp ., Chaetozone sp ., Littorina spp ., Phyllodocidae sp . and Carcinus maenas.

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^[1] URL: http://www.jncc.gov.uk/UKSPA/sites/Scotland/UK9004411.htm