Palaeoecological Assessment of a New Deep water Channel in the Lower River Test - Case Study Example

The Palaeoecological Assessment of a New Deep water Channel in the Lower River Test opposite the Millbrook container terminal at Southampton Institution Introduction Natural England (NE) was asked by Associated British Ports (ABP) to advice on the dredging of a new deep-water channel opposite the Millbrook container terminal at Southampton designed to allow the turning of container vessels. This evaluation was targeted towards the assessment of the palaeoecological and archaeological potential of the sediments and what provisions should be made for their sampling and analysis. The basic interest of the deposit laid on the association with the Eling Wharf. The area to be dredged out was from Eling Wharf to Hythe off the western edge of the New Forest. The region was 100-200m wide and 60m below mean low water level and located entirely within the present estuary and adjacent to the present deep-water channel. This was below the mean low water line. In this regard, palaeoecological and archaeological potential included the sediments that were reasonably encountered and the potential the sediments might have in informing both the scientific community and the public on both the ecological and archaeological history of the area, the relative sea-level history of the estuary and its relationship to regional relative sea-level history. In this case, the archaeological potential refer to evidences of human activity in the sediments and through the palaeoecology including the sea-level history. The prime aim of the assessment was to determine the Palaeoecological assessment of new deep water channel in the Lower River Test. The targeted area was cured using the wide diameter approximately ten cm chamber core that gave a near continuous analysis of the cores. Methods The depths of the sediments were estimated using the ground penetration radar: 200 MHz antennae, and Pulse Ekko Pro system. The measurements were done on the transect lines designed for the representation of the wide range of the sedimentation within the study area. The collected samples were observed and examined inside the laboratory. The samples were described using the subsample pro forma. The subsamples of about two kilogram were utilized in all the cases with the exception of one context that used one kilogram subsample. These subsamples were processed by the standard methods. These methods included the floatation of paraffin so as to extract any type of insects that remained. The remains of sediments were extracted by a washover to have the lighter organic fraction concentrated. The whole volume of the organic and the inorganic fractions together with a heavy mineral fractions were measured. The parts of the sample fractions were recorded especially when still wet. The residue was stored wet, whereas the washover was stored wet. After this, the inspection of the washover was done by the NE who had the nature of the sediments together with the other components recorded. This was done after re-sieving to form the convenient fractions. A semi-quantitative scale having four points of abundance was utilized from few specimens. This was less that the six in each kg raw sediment that was estimated to about four abundant remains. The different specimen in each kilogram or the major matrix component was recorded.. The obtained data was recorded in the laboratory sheet provided for the study. The data was subsequently recorded on personal computers by the help of the Microsoft Access database. For reasons of the technical issues in as far as the computer data handling is concerned the sp(p) convention was used in denoting the idea that more  than a single species was in existence. This was utilized throughout even when there was one specimen recorded on the taxon implying the fact that one species could be in existence. For the remains of plants, CF was used in indicating the appropriate guess to the fossil specimen identity. The resulting flots from the floatation of the paraffin was examines for the macro invertebrate and the insect remains, by the help of the low-power binocular microscope. The obtained fragments were contained in a damp filter paper inside the petri dishes. This was done together with some thymol cystal that prevented the moulds even before they were identified in reference to the manual identification, taxa lists, and the modern specimen established with the required abundance record. The condition of preservation for the remains of insects was recorded by the scales. The gathered preservations were recorded in the form of fragmentation (F) and chemical erosion (E). For each of the cases 0.5 superb to 5.5 fragments that were extremely decayed. The sampled remains were allowed to dry to be stored in the forms that would be accessible. The GPR data was used in mapping the depths of the sediments and the selection of the sediment core location in establishing the time through which the formation of the sediments started across the area under study. In each core, the required depth for which the sediments started to be establish was determined by measuring the core material physical properties. The bulk density decreased, whereas the organic matter increased when the sediments changed to soil. The value pattern from typical cores was recorded. Results The GPR survey showed that the depths of the sediments were not uniform in the area under study but were variable. The deepest sediment recorded about 7.28 and the mean depth of the sediments was slightly about three meter. This was considerably more than the prediction of the model based dept of the sediments for the area under study. The model predictions were used in estimating the total volume of the carbon in Dartmoor sediments. The under-estimation of the real depth for the sediments resulted into under estimation of the carbon volume in the area of the sediments. The deepest sediments were located around the topographic saddles in the area under study and the tributaries of the headwater. The sediments are generally extremely shallow on the slopes that are gentle in the area under study but can realize the excess of about two meter. There were a number of disturbances of the surface sediments that were evident across the area under study that was linked to the extraction of the sediments in the surface erosion of the nineteeth century. GPR lines along the Lower River Test showed two meters depth of the sediments had been extracted by the industrial cutting. This could be an underestimation of the real figure especially when the sediments around the edges of the cuts did shrink due to the effect of drying out. More than 5 m of sediments remained in whatever was referred to as the undisturbed peat between the cutting areas. This showed the deterioration signs with some features of erosion around the edges. The results collected from the dating of the radiocarbon showed the timing initiation of the sediments as being variable in the area under study. The dates for the initiation of the sediments was 11065 to 10562 before the present, and the latest dates were 3902 to 3724 years before the core. The sediment initiation dated across the area under study showing that there were increased differences in the initiation process of the sediments in time and space. This was vital in considering the reasons why the sediments started to form and understanding the spread of sediments across the given landscape. The link between the age and the depth of the sediments was explored to test whether the depth of the sediment could be utilized in estimating the age of the sediments, allowing the model the broad distribution of the sediments in time to e estimated as per the depths of the sediments. The results showed that even though there were sediments below 250 cm, there was no clear pattern for the peat that was shallower than the depth. This implied that the rate of accumulation for the blanket peat varied across the area under the study. Discussion Recognizing the sediment pattern which was variable in the space and the time had high significance for the archaeology. This revealed that the landscapes of prehistoric communities’ inhabitation was equally variable. It included the peat land patches and the dried land that was characterized by open hazel woodland that rely on the previous work results that describe the wide pattern of the history of the vegetation for over seven thousand years ago. Understanding this pattern is vital in reconstructing the manner in which the prehistoric communities may have interacted together with the landscape and also in making prediction on the areas that might preserve the prehistoric archaeological underneath landscape. The Bronze Age began at about 4000 to 4200 years ago. It was not until 3800 years ago that most of the areas of bog blanket that were observed today had started to be established. The archeological sites like that of the Lower River Test are believed to be older than the estimated 3800 years. The identification of the stone row in the area under study shows that it is not certain that the location of the different rows built on the area is not certain. Some sediment could be hidden below the blanket peat in regions that were explored (Parry, L. 2011). The records of the anti quarian showed the discovery of two mostly polished and combined axes of the grey flint from inside the peat worked for walkham head. This gave out the actual proof that the Neolithic communities inhabited the section of the area under study hence the landscape, and the strengthening of the survival possibilities of different structures under the peat. There could be some possibilities that the early Bronze age monument burial was built on the dried land which is buried under the peat or on shallow peaty soil hence the certain possibility of the monuments that are earlier, which were evidenced by the sediments found beneath. The cist excavation showed the fact that the early Bronze Age communities did inhabit and utilized the covered peat that were considered being marginal and remote to the today society. This leaves some possibilities that different archaeological sites could be identified. Whatever was seen to be intact or the undisturbed areas in the deep blanket in regions of extensive cutting can survive by maintaining the positive indication for a long term surviving of the peat archaeology and the peat that was buried under or within the peat in the areas. Conclusion Te study found out the oldest dated peat. The peat for the core 27 started to be established immediately at the final last ice age about 11,000 years ago. The core had a number of potential in describing the manner in which the vegetation displayed the final cold period. There was only one comparable sequence within the area under study core was found to be an area that had large fully running through it which still preserved over 5 m of the sediments until the recent times. The study established that there were possibilities in demonstrating the possible estimation of how much peat would be removed through the extraction of the peat, intact adjacent peat and the cuttings of the peat using the GPR survey (Parry, L., 2011). About 2m depth of the peat was removed. More field work in this region and the different areas of extraction could result into the documentation of the peat extraction. This will give a useful contribution to the pea extraction history. The link between the age and the depth of the sediments was explored to test whether the depth of the sediment could be utilized in estimating the age of the sediments allowing the model the broad distribution of the sediments in time to e estimated as per the depths of the sediments. The results showed that even though there were sediments below 250 cm, there was no clear pattern for the peat that was shallower than the depth. This implied that the rate of accumulation for the blanket peat varied across the area under the study. The results showed that even though there were sediments below 250 cm, there was no clear pattern for the peat that was shallower than the depth. This implied that the rate of accumulation for the blanket peat varied across the area under the study. References Parry, L., 2011. The sustainable carbon management of moorlands: spatial distribution and accumulation of carbon on Dartmoor, southwest. New York : Oxford University press. Read More