USING the SURFACE-FEATURES CREATED by BIOTURBATING ORGANISMS AS SURROGATES for MACROFAUNAL DIVERSITY and COMMUNITY STRUCTURE S Widdicombe, M Kendall, D Parry
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USING THE SURFACE-FEATURES CREATED BY BIOTURBATING ORGANISMS AS SURROGATES FOR MACROFAUNAL DIVERSITY AND COMMUNITY STRUCTURE S Widdicombe, M Kendall, D Parry To cite this version: S Widdicombe, M Kendall, D Parry. USING THE SURFACE-FEATURES CREATED BY BIOTUR- BATING ORGANISMS AS SURROGATES FOR MACROFAUNAL DIVERSITY AND COMMU- NITY STRUCTURE. Vie et Milieu / Life & Environment, Observatoire Océanologique - Laboratoire Arago, 2003, pp.179-186. hal-03205257 HAL Id: hal-03205257 https://hal.sorbonne-universite.fr/hal-03205257 Submitted on 22 Apr 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. VIE MILIEU, 2003, 53 (4) : 179-186 USING THE SURFACE-FEATURES CREATED BY BIOTURBATING ORGANISMS AS SURROGATES FOR MACROFAUNAL DIVERSITY AND COMMUNITY STRUCTURE S. WIDDICOMBE*1,M.A.KENDALL1, D. M. PARRY 2 1 Plymouth Marine Laboratory, Prospect Place, West Hoe, Plymouth, PL1 3DH,UK 2 Institute of Marine Studies, University of Plymouth, Drakes Circus, Plymouth, PL4 8AA,UK * Corresponding author Email: [email protected] SURFACE FEATURES ABSTRACT. – Relationships between the surface features created by infaunal bio- BENTHIC DIVERSITY turbators and the diversity and structure of a macrobenthic community were identi- BIOTURBATION fied at spatial scales of 30 to 100 cm for an area of shallow (10 m) subtidal NON-DESTRUCTIVE MONITORING ≥ MEGAFAUNA sediment at Jennycliff Bay (Plymouth, UK) in May 2000. At spatial scales 80 cm, MACROFAUNA macrofaunal heterogeneity, and diversity, was greater in areas that contained many different surface features compared with areas containing few features. This obser- vation is field evidence to substantiate suggestions that the non-destructive quanti- fication of conspicuous surface features is a useful surrogate of macrobenthic diversity. This surrogate may be most useful in assessing large scale impacts on se- diment habitats such as faunistic changes over long distances, long-term temporal changes in a particular place or assessing differences between habitats or geogra- phical locations. STRUCTURES DE SURFACE RÉSUMÉ. – Des rapports entre les dispositifs de surface créés par des organismes DIVERSITÉ BENTHIQUE fouisseurs et la diversité et la structure d’une communauté macrobenthique ont été BIOTURBATION identifiés aux échelles spatiales de 30 à 100 cm pour un secteur (10 m) de sédiment SURVEILLANCE NON DESTRUCTIVE MÉGAFAUNE subtidal peu profond dans la baie de Jennycliff (Plymouth, R-U) en mai 2000. Aux MACROFAUNE échelles spatiales ≥ 80 cm, l’hétérogénéité de la macrofaune, et la diversité, sont plus élevées dans les secteurs qui contiennent de nombreuses structures extérieures différentes en comparaison avec les secteurs contenant peu de ces dispositifs. Cette observation est une démonstration in situ pour justifier des suggestions selon les- quelles la quantification non destructive des structures de surface remarquables est un substitut utile de la diversité macrobenthique. Ce substitut peut être particulière- ment utile lors de l’évaluation des impacts à grande échelle sur les habitats des sé- diments, tels que les changements faunistiques sur de longues distances, les changements temporels à long terme d’un site particulier ou lors de l’évaluation des différences entre habitats ou localisations géographiques. INTRODUCTION solely a result of differences in the intensity and frequency of disturbance (Widdicombe et al. Bioturbation has a substantial influence on the 2000). Mesocosm studies have shown that the physical and chemical properties of the sediments; intensity of bioturbation and the identity (or burrowing and/or feeding activities can have a functional type) of the bioturbator responsible, strong influence on sediment granulometry, the act simultaneously on different elements of penetration of oxygen, nutrient flux and the fre- macrobenthic communities (Widdicombe & Austen quency of sediment disturbance (e.g. Widdicombe 1999, Widdicombe et al. 2000). Further evidence & Austen 1988, Rowden & Jones 1993, Nedwell & for the importance of sediment complexity in the Walker 1995). As the properties of the sediment maintenance of high diversity macro-infaunal com- change so too does its suitability for colonisation munities was provided by Thrush et al. (2001). and exploitation by secondary species. Bioturbating These authors suggested that between 74 and 86% organisms have been shown to impact on of the variance in macrobenthic diversity was ex- macrobenthic communities both directly through plained by habitat structure. Clearly bioturbation is physical interactions (e.g. predation) and indirectly an important process in producing heterogeneity or through changes in the sediment environment. complexity within the sediment habitat thus main- However, the scale of bioturbation impact is not taining levels of diversity. 180 S. WIDDICOMBE, M. A. KENDALL, D.M. PARRY In the face of growing environmental pressures lected from quantitative remotely operated vehicle on coastal marine ecosystems the need to assess (ROV) observations. Such data have been validated and monitor changes in marine communities is previously against those derived from direct diver greater than ever. In particular, legislation de- observation (Parry et al. 2002) and have proved to signed to protect marine habitats and biodiversity be an accurate and effective representation of the (e.g. EC Habitats Directive 1992) has placed great biogenic landscape. Furthermore, spatial referenc- demands on those responsible for the management ing of ROV images allows mapping of megafaunal of coastal resources. However, traditional methods assemblages within benthic landscapes (Parry et al. of biodiversity assessment that involve the quanti- 2003). fication of entire communities are highly labour in- Through the intensive study of a relatively small tensive and therefore expensive (McIntyre 1983, area of bioturbated seabed, the current study aims Warwick 1993). If efficient monitoring and man- to establish whether a relationship exists between agement is to be achieved over large areas of the identity and abundance of biologically pro- coastal waters, techniques need to be developed duced surface features and the structure and diver- that allow rapid, cost effective assessment of com- sity of infaunal macrobenthic communities. The munity structure and diversity. Such methods do potential of surface features as an accurate surro- not need to deliver outputs with high levels of pre- gate of macrobenthic community structure and di- cision, it is sufficient that they produce information versity is discussed. that is “fit for purpose”. A number of authors (e.g. James et al. 1995, Kendall & Widdicombe 1999) have shown that when assessing the pattern of dis- tribution of benthic assemblages, coarser sieve METHODS meshes or identification to higher taxa produce re- sults that differ little from those produced using a complete survey design. Others have suggested the Sample area: The field sampling was conducted between use of surrogates, elements of the biota whose pres- 30th-31st May 2000 at Jennycliff Bay (50º21.0’N ence predicts biological properties of the whole as- 04º07.8’W), a sheltered bay within Plymouth Sound. semblage. For example, Oslgard & Somerfield This area is an extensive stretch of sandy mud (Marine (2000) suggested that analysis of a small subset of Biological Association 1957) with a water depth of ap- the polychaete fauna might be sufficient to predict proximately 10 m and generally low current speeds. Jen- the diversity of the whole assemblage. Similarly, nycliff Bay supports high megafaunal densities, Warwick & Light (2002) have investigated the use characterised by thalassinidean shrimp (Upogebia del- of molluscan death assemblages on seashores to taura and Callianassa subterranea), Goneplax rhomboi- predict the biodiversity of the adjacent offshore des and several large bivalve species (Parry 2002). fauna. Other studies have shown that it is not al- Patterns in macrobenthic community structure have been well studied at this site (Kendall & Widdicombe 1999). ways necessary to identify organisms to species level as the same patterns of community change Characterisation of biogenic landscape: Megafaunal as- may be observed for data at the family or genus semblage data extracted from remote observations of the level (Warwick 1988, Olsgard et al. 1997). seabed may be considered descriptors of the biological- ly-mediated landscape rather than an absolute estimate Even with a reduced sample processing effort, of megafaunal species abundance because different bur- classical analysis of benthic samples remains both rows have a variable number of surface openings. Never- costly and time consuming. As remote collection of theless, the morphology of surface features may be used benthic sediment is destructive it must be used with to infer the identity of species responsible for burrow great discretion in environmentally sensitive areas. construction (e.g. Nickell & Atkinson 1995). The defini- If the extent of bioturbation and the identity of the tion of megafaunal