256
A. NELSON-SMITH
control the slime, stimulated its growth by about 15% although “ shock
doses ” of 300 p.p.m. phenol killed it.
Further data on algae are anecdotal rather than quantitative.
Extensive algal damage has been reported, for example, by DiazPiferrer (1962) after the wreck of the “ Argea Prima ”. “ Torrey
Canyon ” oil appeared t o cling particularly tenaciously to the laverweed
Porphyra umbilicalis (L.) Xutz. (Rhodophyceae), which subsequently
became discoloured, whilst North and his colleagues noted that red
algae (especially corallines in rock pools) also suffered a discharge of
pigment and are thus perhaps particularly sensitive to oil. Shaw and
Timmons (1949) recommended the use of aromatic hydrocarbons (their
mixture contained a high proportion of xylene) to clear irrigation
channels. An initial concentration of 300 p.p.m., declining to 150-250
p.p.m. downstream of the treatment point, completely eliminated submerged freshwater plants although it had little effect on those with
aerial leaves. Currier and Peoples (1954) found that 740 p.p.m benzene
killed the pondweed Anacharis (Elodea) canadensis Michx. within 1 h,
although a saturated solution of the less soluble (and non-aromatic)
hexane was not lethal.
Mackin (1950a-c) tested the effects of crude oil on salt-marsh plants.
Saltgrass Distychlis spicata (L,), glasswort (Salicornia spp.), cordgrass
(Spartina sp.) and young mangroves (Rhizophora sp.) were more sensitive than oysters. I n one series of experiments they were damaged by
25 ml oil per square ft of water surface (about 280 ml/m2). Some plants
were rapidly killed but there was a complete repopulation later. DiazPiferrer (1962) also found that stranded oil killed mangrove plants.
Cowell and Baker (1969) described the effects of pollution of a saltmarsh by fresh crude oil spilt in Milford Haven from the tanker,
‘‘ Chryssi P. Goulandris ”. The grasses Pestuca rubra L., Puccinellia
maritima (Hds.) Parl. and Spartina townsendii H. & J. Groves
recovered readily; Suaeda maritima (L.) Dun. and Salicornia spp.
recovered only slowly, while Triglochin maritima L., Nalimione
portujacoides (L.) Aell. and Armeria maritima (Mill.) Willd. a t its seaward end showed no recovery in the first year.
studied salt-marshes in Cornwall affected by weathered Oil from the
6‘ Tomey Canyon ”. Experiments by Baker (1969) confirm his observation that fresh oil is more toxic (i.e. the phytotoxic components are
volatile) ; she found that weathered oil has a growth-stimulating effect
and discusses unpublished Russian work suggesting that naPhthenic
acid might act as a phytohormone. In her greenhouse experiments, a
10% solution ofnaphthenic acid applied a t about 170 ml/m2 Was toxic
to P,uccinellia whereas lower concentrations had no obvious effects,
Cowell (196gb)
A. NELSON-SMITH
control the slime, stimulated its growth by about 15% although “ shock
doses ” of 300 p.p.m. phenol killed it.
Further data on algae are anecdotal rather than quantitative.
Extensive algal damage has been reported, for example, by DiazPiferrer (1962) after the wreck of the “ Argea Prima ”. “ Torrey
Canyon ” oil appeared t o cling particularly tenaciously to the laverweed
Porphyra umbilicalis (L.) Xutz. (Rhodophyceae), which subsequently
became discoloured, whilst North and his colleagues noted that red
algae (especially corallines in rock pools) also suffered a discharge of
pigment and are thus perhaps particularly sensitive to oil. Shaw and
Timmons (1949) recommended the use of aromatic hydrocarbons (their
mixture contained a high proportion of xylene) to clear irrigation
channels. An initial concentration of 300 p.p.m., declining to 150-250
p.p.m. downstream of the treatment point, completely eliminated submerged freshwater plants although it had little effect on those with
aerial leaves. Currier and Peoples (1954) found that 740 p.p.m benzene
killed the pondweed Anacharis (Elodea) canadensis Michx. within 1 h,
although a saturated solution of the less soluble (and non-aromatic)
hexane was not lethal.
Mackin (1950a-c) tested the effects of crude oil on salt-marsh plants.
Saltgrass Distychlis spicata (L,), glasswort (Salicornia spp.), cordgrass
(Spartina sp.) and young mangroves (Rhizophora sp.) were more sensitive than oysters. I n one series of experiments they were damaged by
25 ml oil per square ft of water surface (about 280 ml/m2). Some plants
were rapidly killed but there was a complete repopulation later. DiazPiferrer (1962) also found that stranded oil killed mangrove plants.
Cowell and Baker (1969) described the effects of pollution of a saltmarsh by fresh crude oil spilt in Milford Haven from the tanker,
‘‘ Chryssi P. Goulandris ”. The grasses Pestuca rubra L., Puccinellia
maritima (Hds.) Parl. and Spartina townsendii H. & J. Groves
recovered readily; Suaeda maritima (L.) Dun. and Salicornia spp.
recovered only slowly, while Triglochin maritima L., Nalimione
portujacoides (L.) Aell. and Armeria maritima (Mill.) Willd. a t its seaward end showed no recovery in the first year.
studied salt-marshes in Cornwall affected by weathered Oil from the
6‘ Tomey Canyon ”. Experiments by Baker (1969) confirm his observation that fresh oil is more toxic (i.e. the phytotoxic components are
volatile) ; she found that weathered oil has a growth-stimulating effect
and discusses unpublished Russian work suggesting that naPhthenic
acid might act as a phytohormone. In her greenhouse experiments, a
10% solution ofnaphthenic acid applied a t about 170 ml/m2 Was toxic
to P,uccinellia whereas lower concentrations had no obvious effects,
Cowell (196gb)