Audouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls

25-01-2007
Researched byKaren Riley Refereed byThis information is not refereed.
EUNIS CodeA1.444 EUNIS NameAudouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls

Summary

UK and Ireland classification

EUNIS 2008A1.444Audouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls
EUNIS 2006A1.444Audouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls
JNCC 2004LR.FLR.CvOv.AudClaAudouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls
1997 BiotopeLR.LR.Ov.RhoCvRhodothamniella floridula in upper littoral fringe soft rock caves

Description

The upper littoral fringe in the moist dark conditions inside caves on soft rock may be characterized by velvety bands of the red alga Rhodothamniella floridula. In chalk caves, on the east and south-east coast of England, a distinctive assemblage of species occurs, including the brown alga Pilinia maritima and the bright green alga Pseudendoclonium submarinum which often covers the roofs of chalk caves. Where the rock is sufficiently hard, the crustose red alga Hildenbrandia rubra may occur on the cave roofs. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Recorded distribution in Britain and Ireland

Recorded in chalk caves from the Isle of Thanet, Kent (Tittley, 1985) and North Landing, Humberside (George et al., 1988).

Depth range

-

Additional information

No text entered

Listed By

Further information sources

Search on:

JNCC

Habitat review

Ecology

Ecological and functional relationships

Chalk habitats, especially in south east England, are intrinsically low in species richness due to the unusual friable and easily eroded nature of chalk (Anon, 1999e). Caves offer some protection from the environment outside. This biotope is predominantly algae which dominate the rock walls and ceiling of the cave. Dominance of one algal species over another and zonation within the cave depends on light intensity, moisture and temperature (Anand, 1937c). Hard flint intrusions in softer chalk are found at North Landing, where Hildenbrandia rubra is present (George et al., 1988). Characteristic fauna of soft chalk habitats include soft rock-boring invertebrates such as Polydora sp. and Pholas dactylus (Anon, 1999e). Grazers such as Patella vulgata and Littorina saxatilis may also be present.

Seasonal and longer term change

The growth and abundance of the fine green filamentous algae, Pseudendoclonium submarinum (previously described by Anand as Endoderma perforans) and red algae is favoured in winter (Anand, 1937b, c; Tittley & Shaw, 1980; Burrows, 1991).

Habitat structure and complexity

Zonation of algae inside the cave is dependent on light intensity and is therefore vertical (Anand, 1937c). The chalk rock surfaces of caves are mainly unbroken but with shelves, fissures and flint nodules. Characteristic communities in inner parts of caves at <10% full daylight are Rhodothamniella floridula (as Rhodochorton sp.) and chalk-boring algae (Anand, 1937c). The shape of the cave also determines how much light reaches the walls and therefore which species will occur. For instance, on surfaces facing away from the cave entrance red algae may predominate, and on surfaces facing towards the cave entrance there is a dominance of Ulva sp. at a greater distance from the opening (Anand, 1937c). Spray created by wave motion and lack of direct sunlight means that the cave walls and ceilings are kept sufficiently moist for algal growth (Anand, 1937c) and rock crevices may offer protection for small marine invertebrates.

Productivity

Macroalgae produce considerable amounts of dissolved organic carbon which is taken up readily by bacteria and may even be taken up directly by some larger invertebrates. Dissolved organic carbon, algal fragments and microbial film organisms are continually removed by the sea. This may enter the food chain of local ecosystems, or be exported further offshore.

Recruitment processes

Annual variation in recruitment success of algae can have a significant impact on the patchiness of the shore. The propagules of most macroalgae tend to settle near the parent plant (Schiel & Foster, 1986; Norton, 1992; Holt et al., 1997). Red algal spores and gametes are immotile. Norton (1992) noted that algal spore dispersal is probably determined by currents and turbulent deposition (zygotes or spores being thrown against the substratum). The reach of the furthest propagule and useful dispersal range are not the same thing and recruitment usually occurs on a local scale, typically within 10m of the parent plant (Norton, 1992). Vadas et al. (1992) noted that post-settlement mortality of algal propagules and early germlings was high, primarily due to grazing, canopy and turf effects, water movement and desiccation and concluded that algal recruitment was highly variable and sporadic. However, macroalgae are highly fecund so that recruitment may still be rapid. Many species of epifauna, such as Patella vulgata, Littorina saxatilis and polychaetes that may be associated with rock crevices, have long lived pelagic larvae and/or are highly motile as adults.

Time for community to reach maturity

No information was found concerning time for community to reach maturity. However, as algae are generally highly fecund, it is likely that maturity will be reached rapidly.

Additional information

No text entered

Preferences & Distribution

Recorded distribution in Britain and IrelandRecorded in chalk caves from the Isle of Thanet, Kent (Tittley, 1985) and North Landing, Humberside (George et al., 1988).

Habitat preferences

Depth Range
Water clarity preferences
Limiting Nutrients Nitrogen (nitrates)
Salinity
Physiographic
Biological Zone
Substratum
Tidal
Wave
Other preferences No text entered

Additional Information

The chalk at North Landing is harder than on the Isle of Thanet and flint intrusions are present, enabling the growth of Hildenbrandia rubra. The distribution of this biotope is limited to suitable environmental conditions on suitable rock surfaces (e.g. chalk caves) many of which have been affected by the construction of sea defences resulting in loss of this biotope in parts of the UK (Marine Task Force, 1993).

Species composition

Species found especially in this biotope

    Rare or scarce species associated with this biotope

    -

    Additional information

    Species richness in chalk habitats is considered to be low (Anon, 1999e). Approximately 10 species have been recorded in this biotope by Connor et al. (1997b) and 29 species by JNCC (1999).

    Sensitivity reviewHow is sensitivity assessed?

    Explanation

    Rhodothamniella floridula is the main characterizing species of the biotope. If this species was absent the biotope would not be recognised. Although other algal species are present within the biotope, they are not considered to be structurally or functionally important. However, their sensitivity will also be taken into account.

    Species indicative of sensitivity

    Community ImportanceSpecies nameCommon Name
    Important characterizingRhodothamniella floridulaA red seaweed

    Physical Pressures

     IntoleranceRecoverabilitySensitivitySpecies RichnessEvidence/Confidence
    High High Moderate Major decline High
    The community is dominated by algae which form permanent attachments to the substratum. Removal of the substratum would remove these species and slow moving species associated with them. Intolerance has been assessed to be high. Recoverability is likely to be high (see additional information below).
    Intermediate High Low Minor decline Moderate
    A 5cm covering of sediment is likely to be washed away with the wave motion against the cave walls. Whilst smothering is generally unlikely on the vertical walls of caves, it may occur at the base of the walls. Impermeable materials, such as concrete, oil, or tar, are likely to have a greater effect. An intolerance of intermediate is recorded. A recoverability of high is recorded (see additional information below).
    Tolerant Not relevant Not relevant No change Low
    As the species in the biotope are probably adapted to high suspended sediment concentrations a sensitivity of 'not sensitive' has been recorded.
    Low High Low Major decline High
    Rhodothamniella floridula needs sediment to bind to and will therefore need enough available to do so. If less suspended sediment is available for the species to bind to then it is likely that colonization of bare substratum would be prevented and a reduction in the abundance of Rhodothamniella floridula may occur. Other algae will probably not be affected. Intolerance has been assessed to be low. Recoverability is likely to be high (see additional information below).
    Intermediate High Low No change High
    Caves are kept moist, due to wave splash and lack of direct sunlight. However if wave splash was stopped due to coastal defences desiccation is likely to occur. Little is known of the desiccation tolerance of Rhodothamniella floridula, it may be protected further from desiccation by the water held in the sand it binds with. Intolerance has been assessed as intermediate.
    Intermediate High Low Minor decline Low
    An increase in emergence is likely to shift the distribution of Rhodothamniella floridula lower down the shore if suitable habitats exist. Replacement may occur by other flora and fauna more tolerant of desiccation. Some mortality of key species is likely, so an intolerance of intermediate has been recorded. Recoverability is likely to be high (see additional information below).
    Intermediate High Low Major decline Low
    Decreases in emergence may put the algal species in competition with species that typically remain submerged (e.g. laminarians). This could result in a depression in the limits of the LR.RhoCv biotope or a shift of the biotope. An intermediate intolerance has been recorded. Recoverability has been assessed to be high (see additional information below).
    Tolerant Not relevant Not sensitive No change Moderate
    Moderate water movement is beneficial to seaweeds as it carries a supply of nutrients and gases to the plants and removes waste products. No information has been found on tolerance of the biotope to water flow rates. This biotope occurs in wave exposed situations (Connor et al., 1997b) where the forces of wave surge are likely to be much more damaging than an increase in tidal flow. However, an increase to stronger flows may inhibit settlement of spores and remove adults or germlings. Water flow would probably be reduced inside the enclosed caves compared to outside. It is unlikely therefore that the benchmark increase in water flow rate would result in mortality. Therefore, the biotope is probably relatively tolerant of increases in water flow.
    Tolerant* Not sensitive No change Moderate
    Moderate water movement is beneficial to algae, mussels and barnacles as it provides a supply of food and nutrients to the organism and also helps to remove waste products. A decrease in water flow rate would also mean that scour decreased and it is possible that Rhodothamniella floridula could be out-competed by other species that thrive in environments lacking scour. In areas where wave energy is low, tidal flow may be important in supplying suspended sediment to the biotope and encouraging growth of Rhodothamniella floridula over other species. In such situations a decrease in water flow rate may cause a different biotope to develop. Mortality of key species is likely to occur and a decrease in growth and respiration/photosynthesis is probable. Intolerance has been assessed to be intermediate. Recoverability has been assessed to be high (see additional information below).
    Low High Low No change High

    Maximum sea surface temperatures around the British Isles rarely exceed 20 °C (Hiscock, 1998) and, as Rhodothamniella floridula occurs south of the British Isles, an increase in temperature is not likely to cause mortality. An acute change in temperature may cause photosynthesis and growth to be impaired, compensating for increased spore production. For instance, spore production of Rhodothamniella floridula is higher at higher temperatures (Stegenga, 1978). Increase in air temperature may cause desiccation, bleaching or death to at least the outer fronds.

    No mortality of key species is likely to occur, although physiological compensation may take place. Therefore, intolerance has been assessed to be low. When temperatures return to normal, respiration, reproduction and growth will quickly recover. Recoverability has been assessed to be very high.

    Intermediate High Low Minor decline Moderate

    Minimum surface sea water temperatures rarely fall below 5 °C around the British Isles (Hiscock, 1998). The distribution of Rhodothamniella floridula has not been recorded north of the British Isles and may not be able to survive a chronic decrease in temperature. However, Dixon & Irvine (1977) observed that Rhodothamniella floridula (as Audouinella floridula) grows much faster in winter, but low temperatures may delay or slow reproduction (Stegenga, 1978).

    As mortality of characterizing species may occur if chronic changes in temperature occur, intolerance has been assessed to be intermediate. When temperature returns to normal, respiration, reproduction and growth will quickly recover in surviving species. Recoverability has been assessed to be high (see additional information below).

    Low Very high Very Low No change High
    An increase in turbidity will probably have little direct effect on the key species within this biotope. However, it may cause a reduction in the photosynthetic capability and growth of algae, but will probably not result in any mortality. Intolerance has been assessed to be low. On return to normal conditions recoverability is likely to be high.
    Tolerant Not sensitive* No change Moderate
    A decrease in turbidity may mean that more light is available for photosynthesis. However, as the biotope occurs at <10% of natural daylight (Anand, 1937c) and has been recorded near Flamborough Head (George et al., 1998) , where low turbidity is usually present (Marine Task Force, 1993), it has been assessed to be 'not sensitive'.
    High High Moderate Major decline Low
    The LR.RhoCv biotope occurs on moderately exposed coasts (Connor et al., 1997b). Increased wave action above this level may cause damage to individual plants, breaking fronds and removing entire plants from the substratum. There may also be increased erosion of the substrate and growths of Rhodothamniella floridula may become dislodged, leading to susceptible patchiness. Therefore, intolerance has been assessed to be high. Recoverability is likely to be high (see additional information below).
    Tolerant* Not sensitive No change Moderate
    Chalk caves are carved into the shoreline by wave action. The LR.RhoCv biotope only occurs on wave exposed shores (Connor et al., 1997b) within these caves. However, characteristic species within the biotope are unlikely to be intolerance of a decrease in wave exposure and may actually benefit. The biotope has been assessed to be being 'not sensitive*' to a decrease in wave exposure.
    Tolerant Not relevant Not relevant No change High
    Seaweeds have no known mechanism for detection of noise vibrations. The biotope has been assessed to be not sensitive to noise.
    Tolerant Not relevant Not relevant Not relevant High
    Seaweeds are unable to detect visual presence. An assessment of 'not sensitive' has been made.
    Intermediate High Low Major decline Moderate
    Upper littoral fringe caves are unlikely to be impacted by physical disturbance from anchorage or dredging. However, soft rocks are friable, and physical disturbance may be caused by pebbles, rocks, or marine debris, which accumulates in caves when moved by wave action. Although algal species are highly flexible, abrasion is likely to cause damage to and removal of fronds and may even remove entire plants from the substratum. The cushion-like base of turf forming algae (such as Rhodothamniella floridula) may offer some protection against abrasion but if a portion is removed, the sharp edges may be subject to lifting by wave action. Intolerance has been assessed to be intermediate. Recoverability is likely to be high (see additional information below).
    High High Moderate Major decline High
    Rhodothamniella floridula and other algae are permanently attached to the substratum. If removed, the attachment cannot be reformed. Therefore, intolerance has been assessed to be high. Recoverability is likely to be high (see additional information below).

    Chemical Pressures

     IntoleranceRecoverabilitySensitivityRichnessEvidence/Confidence
    High High Moderate Major decline Moderate
    Rhodothamniella floridula is likely to be highly intolerant of synthetic chemical contamination. O'Brien & Dixon (1976) suggested that red algae were the most sensitive group of algae to oil or dispersant contamination. Laboratory studies of the effects of oil and dispersants on several red algal species concluded that they were all sensitive to oil/dispersant mixtures, with little difference between adults, sporelings, diploid or haploid stages (Grandy, 1984, cited in Holt et al., 1995). Cole et al. (1999) suggested that herbicides, such as simazine and atrazine were very toxic to macrophytes. Therefore, a high intolerance has been recorded. Recovery is likely to be high (see additional information below).
    Heavy metal contamination
    Intermediate High Low Major decline Low
    Bryan (1984) suggested that the general order for heavy metal toxicity in seaweeds is: Organic Hg > inorganic Hg > Cu > Ag > Zn > Cd > Pb. Cole et al. (1999) reported that Hg was very toxic to macrophytes. The sub-lethal effects of Hg (organic and inorganic) on the sporelings of an intertidal red algae, Plumaria elegans, were reported by Boney (1971). 100% growth inhibition was caused by 1 ppm Hg. Intolerance has been assessed to be intermediate. Recoverability is likely to be high (assuming deterioration of contaminants) (see additional information below).

    Hydrocarbon contamination
    High High Moderate Major decline Moderate
    No evidence was found specifically relating to the intolerance of Rhodothamniella floridula to hydrocarbon contamination. However, inferences may be drawn from the sensitivities of red algal species generally. O'Brien & Dixon (1976) suggested that red algae were the most sensitive group of algae to oil or dispersant contamination. Laboratory studies of the effects of oil and dispersants on several red algal species concluded that they were all sensitive to oil/dispersant mixtures, with little difference between adults, sporelings, diploid or haploid life stages (Grandy, 1984, cited in Holt et al., 1995). Therefore intolerance has been assessed to be high. Recoverability has been assessed to be high (see additional information below).

    Radionuclide contamination
    No information Not relevant No information Insufficient
    information
    Not relevant
    No information concerning the effects of radionuclides on species within the biotope was found and 'insufficient information' has been recorded.
    Changes in nutrient levels
    Intermediate High Low Minor decline Moderate
    Nutrient availability is the most important factor controlling algal germling growth. Plants under low nutrient regimes achieve smaller sizes and may be out-competed. A moderate increase in nutrient levels may enhance their growth. However, if nutrient loading is excessive this can have a detrimental effect on algal productivity. Therefore, intolerance has been assessed to be intermediate. Recoverability is likely to be high ( see additional information below).
    Low High Low No change Moderate
    The LR.RhoCv biotope occurs in full salinity. Therefore a low intolerance has been recorded. Recoverability is likely to be very high.
    High High Intermediate Major decline High
    The LR.RhoCv biotope occurs only in full salinity conditions. It is probable that a proportion of the population would die in lower salinities, or at least be out-competed by brackish water tolerant species. Intolerance has been recorded to be high. Recoverability is likely to be high (see additional information below).
    Intermediate High Low Minor decline Moderate
    The effects of reduced oxygenation on algae are not well studied. Plants require oxygen for respiration, but this may be provided by production of oxygen during periods of photosynthesis. Lack of oxygen may impair both respiration and photosynthesis (see review by Vidaver, 1972). A study of the effects of anoxia on Delesseria sanguinea (a red algae), revealed that specimens died after 24 hours at 15°C but that some survived at 5°C (Hammer, 1972). Cole et al. (1999) suggest possible adverse effects on marine species below 4 mg/l and probable adverse effects below 2mg/l. As some important species within the biotope may die, an intermediate intolerance has been recorded. Recoverability is likely to be high (see additional information below).

    Biological Pressures

     IntoleranceRecoverabilitySensitivityRichnessEvidence/Confidence
    No information Not relevant No information Insufficient
    information
    Not relevant
    No information relating to the effects of microbial pathogens on the key species within the biotope was found.
    No information Not relevant No information Insufficient
    information
    Not relevant
    No information was found on alien species that may compete with species within the biotope.
    Not relevant Not relevant Not relevant Not relevant Not relevant
    It is extremely unlikely that any of the species indicative of sensitivity would be targeted for extraction and we have no evidence for the indirect effects of extraction of other species on this biotope.
    No information Not relevant No information Insufficient
    information
    Not relevant

    Additional information

    Recoverability
    Following a major loss of the main characterizing species there will be a colonization succession. No information was found relating to colonization or recolonization rates of Rhodothamniella floridula, however, sand-binding algal species, such as Rhodothamniella floridulaare able to colonize soft or crumbly rock more successfully than fucoids (Lewis, 1964). Red algae are typically highly fecund, but their spores are non-motile (Norton, 1992) and therefore highly reliant on the hydrodynamic regime for dispersal. Kain (1975) reported that after displacement some Rhodophyceae were present after 11 weeks, and after 41 weeks, in June, Rhodophyceae species predominated. However, Stegenga (1978) noted that tetrasporangia of Rhodothamniella floridula (as Rhodochorton floridulum) germinated in 'rather low numbers'. Recoverability of the biotope has been assessed as high, although recovery of remote populations will be more protracted and dependent upon favourable currents bringing spores.

    Importance review

    Policy/Legislation

    Habitats Directive Annex 1Reefs, Submerged or partially submerged sea caves
    UK Biodiversity Action Plan Priority

    Exploitation

    The biotope is not exploited but is threatened by coastal defence works.

    Additional information

    The actions of the littoral and sublittoral chalk habitat action plan are linked closely to those of the maritime cliff and slopes habitat action plan. In both plans attention is drawn to the need for avoiding non-sustainable coastal defence works and of raising awareness of the biodiversity and dynamic nature of these habitats and their role in coastal processes (Anon, 1999e). Subtidal chalk habitats have been identified within Sensitive Marine Areas and Voluntary Marine Conservation Areas (VMCA). The statutory protection of littoral and sublittoral chalk habitats is now possible at four sites, Flamborough Head, Thanet Coast, South Wight and Rathlin Island, through their candidature as SACs (Anon, 1999e).

    Bibliography

    1. Anand, P.L., 1937b. An ecological study of the algae of the British chalk cliffs. Part I. Journal of Ecology, 25, 153-188.
    2. Anand, P.L., 1937c. An ecological study of the algae of the British chalk cliffs. Part II. Journal of Ecology, 25, 344-367.
    3. Anonymous, 1999e. Littoral and sublittoral chalk. http://www.ukbap.org.uk/ukplans.aspx?id=31, 2001-09-26
    4. Boney, A.D., 1971. Sub-lethal effects of mercury on marine algae. Marine Pollution Bulletin, 2, 69-71.
    5. Bryan, G.W., 1984. Pollution due to heavy metals and their compounds. In Marine Ecology: A Comprehensive, Integrated Treatise on Life in the Oceans and Coastal Waters, vol. 5. Ocean Management, part 3, (ed. O. Kinne), pp.1289-1431. New York: John Wiley & Sons.
    6. Burrows, E.M., 1991. Seaweeds of the British Isles. Volume 2. Chlorophyta. London: British Museum (Natural History).
    7. Cole, S., Codling, I.D., Parr, W. & Zabel, T., 1999. Guidelines for managing water quality impacts within UK European Marine sites. Natura 2000 report prepared for the UK Marine SACs Project. 441 pp., Swindon: Water Research Council on behalf of EN, SNH, CCW, JNCC, SAMS and EHS. [UK Marine SACs Project.], http://www.ukmarinesac.org.uk/
    8. Connor, D.W., Brazier, D.P., Hill, T.O., & Northen, K.O., 1997b. Marine biotope classification for Britain and Ireland. Vol. 1. Littoral biotopes. Joint Nature Conservation Committee, Peterborough, JNCC Report no. 229, Version 97.06., Joint Nature Conservation Committee, Peterborough, JNCC Report No. 230, Version 97.06.
    9. Davies, C.E. & Moss, D., 1998. European Union Nature Information System (EUNIS) Habitat Classification. Report to European Topic Centre on Nature Conservation from the Institute of Terrestrial Ecology, Monks Wood, Cambridgeshire. [Final draft with further revisions to marine habitats.], Brussels: European Environment Agency.
    10. Dixon, P.S. & Irvine, L.M., 1977. Seaweeds of the British Isles. Volume 1 Rhodophyta. Part 1 Introduction, Nemaliales, Gigartinales. London: British Museum (Natural History) London.
    11. George, J.D., Tittley, I., Price, J.H., & Fincham, A.A., 1988. The macrobenthos of chalk shores in North Norfolk and around Flamborough Headland (North Humberside). Nature Conservancy Council CSD Rep. 833 149p., Peterborough: Nature Conservancy Council
    12. Grandy, N., 1984. The effects of oil and dispersants on subtidal red algae. Ph.D. Thesis. University of Liverpool.
    13. Hammer, L., 1972. Anaerobiosis in marine algae and marine phanerograms. In Proceedings of the Seventh International Seaweed Symposium, Sapporo, Japan, August 8-12, 1971 (ed. K. Nisizawa, S. Arasaki, Chihara, M., Hirose, H., Nakamura V., Tsuchiya, Y.), pp. 414-419. Tokyo: Tokyo University Press.
    14. Hiscock, K., ed. 1998. Marine Nature Conservation Review. Benthic marine ecosystems of Great Britain and the north-east Atlantic. Peterborough, Joint Nature Conservation Committee.
    15. Holt, T.J., Hartnoll, R.G. & Hawkins, S.J., 1997. The sensitivity and vulnerability to man-induced change of selected communities: intertidal brown algal shrubs, Zostera beds and Sabellaria spinulosa reefs. English Nature, Peterborough, English Nature Research Report No. 234.
    16. Holt, T.J., Jones, D.R., Hawkins, S.J. & Hartnoll, R.G., 1995. The sensitivity of marine communities to man induced change - a scoping report. Countryside Council for Wales, Bangor, Contract Science Report, no. 65.
    17. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line] http://www.jncc.gov.uk/mermaid,
    18. Lewis, J.R., 1964. The Ecology of Rocky Shores. London: English Universities Press.
    19. Marine Task Force, 1993. Sensitive Marine Areas in England. First Draft. English Nature Report, Campaign for a Living Coast.
    20. Norton, T.A., 1992. Dispersal by macroalgae. British Phycological Journal, 27, 293-301.
    21. O'Brien, P.J. & Dixon, P.S., 1976. Effects of oils and oil components on algae: a review. British Phycological Journal, 11, 115-142.
    22. Schiel, D.R. & Foster, M.S., 1986. The structure of subtidal algal stands in temperate waters. Oceanography and Marine Biology: an Annual Review, 24, 265-307.
    23. Stegenga, H., 1978. The life histories of Rhodochorton purpureum and Rhodochorton floridulum (Rhodophyta, Nemiales) in culture. British Phycological Journal, 13, 279-289.
    24. Tittley, I. & Shaw, K.M., 1980. Numerical and field methods in the study of the marine flora of chalk cliffs. In The shore environment, vol. 1: methods (ed. J.H. Price, D.E.G. Irvine & W.F. Farnham), pp. 213-240. London & New York: Academic Press. [Systematics Association Special Volume, no. 17(a).]
    25. Tittley, I., 1985. Chalk cliff algal communities of Kent and Sussex, Southeast England. Nature Conservancy Council, Contract Reports, no. 200., Peterborough: Nature Conservancy Council.
    26. Vadas, R.L., Johnson, S. & Norton, T.A., 1992. Recruitment and mortality of early post-settlement stages of benthic algae. British Phycological Journal, 27, 331-351.
    27. Vidaver, W., 1972. Dissolved gases - plants. In Marine Ecology. Volume 1. Environmental factors (3), (ed. O. Kinne), 1471-1490. Wiley-Interscience, London.

    Citation

    This review can be cited as:

    Riley, K. 2007. Audouinella purpurea and Cladophora rupestris on upper to mid-shore cave walls. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. Available from: http://www.marlin.ac.uk/habitat/detail/39

    Last Updated: 25/01/2007