The kelp fauna of northeast Britain. I. Introduction and the physical environment

Abstract

As part of a multidisciplinary investigation of pollution in northeast Britain a study of the sublittoral kelp fauna is described. Sampling strategy is discussed and a programme adopted involving the investigation of an instantaneous faunal pattern over a wide area and its environmental correlation. The kelp holdfast as a sample unit is briefly evaluated. The total faunal content of the survey samples is described in gross terms. A review of the physical parameters which impinge upon the holdfast fauna is made and on this basis significant variables are resolved into turbidity, pollution, water movement, and holdfast morphology. Detailed treatment of these factors follows and their distribution over the northeast coast transect is described. Seasonal studies on suspended solids enable an approximate area north of the River Coquet in Northumberland to be considered as continually clear, whilst the area to the south is considered turbid. The region of turbid water is considered to be the consequence of erosion of superficial coastal deposits under the action of marine and atmospheric forces. The rôle of discharges in contributing to suspended solids is considered. Nutrient data are given; the amounts were spatially similar over the whole coastline. An area of ‘pollution’ is provisionally designated on the basis of published figures. The problems of assessment of wave exposure and present inadequate knowledge of local inshore current systems preclude other than crude separation of one site on considerations of water movement. Holdfast parameters are generally interdependent: however the degree of holdfast branching is shown to be independent of age and to influence significantly (along with water movement external to the holdfast) the degree of holdfast silting.