Land Ocean Interaction Study Research Articles

Nitrogen and phosphorus in east coast British rivers: Speciation, sources and biological significance

The data on nitrogen and phosphorus fractions obtained during the core study programme of the Land Ocean Interaction Study for rivers draining the central part of eastern UK are presented and assessed with respect to sources and potential biological effects. The approaches used include comparisons of: (1) overall speciation of nitrogen and phosphorus in the rivers by examining average values and ranges; (2) relationships between nitrogen and phosphorus fractions and flow; and (3) relationships between nitrate and total dissolved nitrogen and soluble reactive phosphorus and total dissolved phosphorus. In addition, comparisons are made between data from the LOIS study region and literature on rivers elsewhere in Europe and North America. Detailed consideration is given to N/P mass ratios in river water, because these can indicate conditions of potential N- or P-limitation for algal and other plant growth. A mid-river site in the Ure, a tributary of Yorkshire Ouse, showed 44% of samples with a N/P mass ratio of>24. Comparison of records for the `growing season' (April to September), when algal and other plant activity is highest, with those from the `dormant season' (October to March) showed a much higher N/P mass ratio during the growing season, indicating that conspicuous growths of Cladophora glomerata and other submerged plants may be reducing ambient phosphate to levels of marked phosphorus limitation.

LISP-UK Littoral Investigation of Sediment Properties: an introduction

Abstract The Humber estuary on the east coast of England was selected as the study area by the UK Natural Environment Research Council (NERC) as the focus of the Land Ocean Interaction Study (LOIS) Community Research Programme. LISP-UK stands for Littoral Investigation of Sediment Properties, and is a Special Topic funded directly by LOIS. LISP-UK is concerned with the dynamics of sediment transport to and from the intertidal mudflats within the Humber estuary. This paper describes the historical, scientific and logistical basis of LISP, and provides the regional setting of the mudflat field area as a preface to LISP-related papers appearing in this volume.

Ground and airborne radiometry over intertidal surfaces: Waveband selection for cover classification

Airborne remote sensing using a Compact Airborne Spectrographic Imager (CASI) has been used to map intertidal surfaces (vegetated and unvegetated at low tide) on the East Coast of England for the Land-Ocean Interaction Study (LOIS). This paper describes how ground radiometry with a Spectron spectroradiometer has been used to examine spectra for a range of surfaces and to compare different CASI bandsets for discrimination of different classes of intertidal vegetation and sediments. CASI in spatial mode records data in up to 14 programmable wavebands in the visible and near-infrared spectral range. Different CASI bandsets have been devised for different purposes (some within this project with the aid of Spectron data). A range of these bandsets are compared on simulated CASI data derived from Spectron ground radiometry. Principal component analysis and discriminant analysis show that these CASI bandsets are capable of separating spectra from 10 key surfaces, but that the various bandsets differ little in their effectiveness and that precise waveband selection is not critical.

The use of NOSTRADAMUS, a numerical transport model, for simulating concentrations and distributions of chromium, cadmium and lead in the Southern North Sea

A numerical transport model, named NOSTRADAMUS, has been developed to simulate concentrations and distributions of a range of EU List I and II metals, including Cr, Cd and Pb in the water column of the southern North Sea. For Cd and Pb, the model takes advantage of data obtained during the observational phase of the Natural Environment Research Council (NERC) North Sea Project (NSP) during 1988–89 to drive the model and to test the results of model simulations. For Cr, there are no water column measurements from the NSP, and so data from other studies, including those from the more recent NERC LandOcean Interaction Study (LOIS), have been used to assess model results.

Rivers and coastal research in the Land Ocean Interaction Study

The UK's large scale research initiative, the Land Ocean Interaction Study (LOIS), began in 1993. It parallels and links to current international scientific interest in land/sea interaction. The development, structure and research activities included in the highly integrated programme are described, with particular attention to the rivers, estuaries and coastal research. Riverine and estuarine sediment transport, water chemistry and biological studies, in addition to model development databasing and remote sensing activities are briefly described.

Monitoring and preliminary interpretation of in-river turbidity and remote sensed imagery for suspended sediment transport studies in the Humber catchment

Rivers are the main source of sediment to the marine environment in global terms. This sediment is predominantly suspended sediments. Calculation of suspended sediment flux requires the combination of suspended sediment concentration and water discharge records. A continuous record of suspended sediment concentration is derived for Land Ocean Interaction Study (LOIS) river monitoring sites using an innovative dual turbidity sensor system. Calibration of turbidity data, to provide a record of suspended sediment concentration, is achieved by comparisons with bulk water/sediment samples collected from Humber rivers, covering the full turbidity range usually encountered in British rivers. The equipment, methodlologies and preliminary results are described, along with the potential errors and limitations. One of the functions of remote sensed data is to help understand the applicability of such point measurements. LOIS is using such data, acquired by imaging spectrometers mounted in an aircraft, to map the spatial distribution of suspended sediment concentration. A semi-empirical relationship has been developed between suspended sediment concentrations and the irradiance reflectance recorded in a near infra red band by the compact airborne spectral imager (CASI). The resulting data on the spatial distribution of suspended sediment concentration are illustrated by an example from the lower part of the River Ouse, Yorkshire. The next stage of the programme will integrate the field science and remote sensing studies with other LOIS rivers research on particle properties, river bank erosion and sediment source studies.

Conclusions to the special volume of science of the total environment concerning UK fluxes to the North Sea, land ocean interaction study river basins research, the first two years

An overview of the regional water quality of rivers draining into the North Sea, based on the first findings of the Land Ocean Interaction Study (LOIS), sets the findings within a contemporary and historical setting. Attention is focused on future avenues of enquiry linking scientific research and environmental management within a framework for safeguarding and improving UK rivers and coastal environments.

Quality simulation along rivers (QUASAR): an application to the Yorkshire Ouse

The water quality model QUASAR (Quality Simulation Along Rivers) has been applied as part of the UK LOIS (Land Ocean Interaction study) project to simulate water quality in the Yorkshire Ouse. QUASAR has been calibrated using data obtained by the Yorkshire and Northumbria region of the Environment Agency (EA) in 1990, and validated using data collected for 1991 to 1993. A new methodology is outlined for estimating flows and water quality for the important ungauged tributaries in this river network. Results show that QUASAR can be used to simulate flow and water quality in a complex river systems such as the Yorkshire Ouse. The importance of accounting for point source and non-point source pollution is illustrated. Results of a basic sensitivity analysis of the model applied to one of the rivers of this system is also described.

The rivers database and the overall data management for the Land Ocean Interaction Study programme

This paper describes the approach taken for the acquisition, management, dissemination and long term security of the environmental data gathered for the Land Ocean Interaction Study (LOIS). The issues that had to e resolved can be divided into two groups: scientific and managerial. Scientific issues centred on how best to hold such a wide variety of spatially and temporally referenced data so that researchers could study cross component processes with ease. Managerial issues concerned policy and operation.

Integrated continuous water quality monitoring for the LOIS river syndromme

This paper describes the installation and operation of an integrated system for the measurement of suspended sediments for the Land-Ocean Interaction Study (LOIS) Rivers Programme. The system is designed to log a continuous record of turbidity and stage and to provide for the acquisition of river samples automaticall, according to programmable sampling strategies. These strategies allow for different sampling rates to be employed throughout an event, so that an appropriate and efficient match between the river conditions and the acquisition of samples can be made. The system components and operating procedures are detailed and results are presented that show the successful operation of the instrumentation.

Fostering cross‐sectorial cooperation: The role of GIS in elucidating biological influences on intertidal areas within the land ocean interaction study

The Biological Influences On inter‐Tidal Areas (BIOTA) project is part of the Natural Environment Research Council's Land Ocean Interaction Study (LOIS). LOIS is a 6‐year program to quantify the exchange, transformation, and storage of materials between the land and the deep ocean and to determine how these parameters change in time and space. Scientific research within the BIOTA program concentrates on the intertidal zone but must also address influences from both land‐ and sea‐based phenomena. Models and data from a wide variety of disciplines have been integrated within a developing GIS‐based spatial decision support system (DSS). While the system is designed primarily to stimulate scientific cooperation and information exchange between researchers, it also provides secure and convenient access to a wide variety of data and models and will provide an aid for effective coastal management. The use of the system in fostering cooperation among researchers is illustrated with reference to a saltmarsh sediment model, where links to conservation biology, climate change, economics, and land use change have been simulated.