Bryophytes of Atewa Forest, Eastern Region, Ghana
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Journal of Bryology ISSN: 0373-6687 (Print) 1743-2820 (Online) Journal homepage: http://www.tandfonline.com/loi/yjbr20 Bryophytes of Atewa Forest, Eastern Region, Ghana N. G. Hodgetts, M. K. Essilfie, A. Adu-Gyamfi, E. Akom, J. Kumadoh & J. Opoku To cite this article: N. G. Hodgetts, M. K. Essilfie, A. Adu-Gyamfi, E. Akom, J. Kumadoh & J. Opoku (2016): Bryophytes of Atewa Forest, Eastern Region, Ghana, Journal of Bryology, DOI: 10.1080/03736687.2016.1145525 To link to this article: http://dx.doi.org/10.1080/03736687.2016.1145525 Published online: 13 Jun 2016. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=yjbr20 Download by: [Nick Hodgetts] Date: 13 June 2016, At: 06:20 Bryophytes of Atewa Forest, Eastern Region, Ghana N. G. Hodgetts1, M. K. Essilfie2, A. Adu-Gyamfi2,E.Akom3, J. Kumadoh3, J. Opoku3 115 Earlish, Portree, Isle of Skye, UK, 2Department of Botany, University of Ghana, Legon, Accra, Ghana, 3A Rocha Ghana, Kaneshie, Accra, Ghana Atewa Forest is a biodiverse tropical forest in the Eastern Region of Ghana, highly threatened by illegal mining, farming and hunting activities, and by proposals for industrial-scale bauxite mining. Conservation bodies are active in trying to save the forest and promote its future as a national park. Very little is known about its bryophyte flora, and this short expedition was intended as a first step to remedy that situation. Survey work in March 2014 was targeted mainly at areas thought likely to be bryophyte-rich, notably swamp forest and upland evergreen forest. A total of 164 species was recorded, including about 58 new to Ghana and at least one new species. The importance of Atewa Forest for biodiversity in western Africa is reinforced. Keywords: Africa, Conservation, Ecology, Inventory, Liverworts, Mosses, Rainforest, Survey Introduction important sources of domestic, agricultural and indus- Atewa (or Atiwa) Forest, located in south-eastern trial water for local communities as well as for many of Ghana, is one of the largest remaining areas of rainfor- Ghana’s major population centres, including Accra. est in the country, covering 23,665 ha and reaching an The forest is under threat from numerous pressures, altitude of 842 m, the second highest point in Ghana. including illegal farming, gold-mining and hunting. The Atewa range of hills runs roughly from north to Even more seriously, the whole forest is under a poten- south and is characterised by a series of forested pla- tial threat from industrial-scale bauxite mining. Set teaux. It represents about 33.5% of the remaining against this, there is an active campaign to keep the closed forest in Ghana’s Eastern Region, harbouring forest more or less intact for its biodiversity, ecosystem a high diversity of species, including vascular plants, services and eco-tourism. A Rocha Ghana, part of the butterflies, dragonflies, katydids, amphibians and international conservation organisation A Rocha, is in Downloaded by [Nick Hodgetts] at 06:20 13 June 2016 birds. There are many endemic and rare species. Some the forefront of this campaign, along with Permian of the seasonal marshy grasslands, swamps and thickets Global and IUCN (Ghana and Netherlands), and is on the Atewa plateaux are nationally unique, and it is making great strides in promoting the forest as a one of only two reserves in Ghana with upland ever- potential national park, educating the local population green forest (Hall & Swaine, 1981). The known biodi- and campaigning at both national and international versity of Atewa Forest was summarised in a ‘rapid levels. McCullough et al. (2007) covered vascular biological assessment’ by McCullough et al. (2007). plants, birds, mammals, reptiles, amphibians and Atewa Forest was established as a national forest several groups of invertebrates, but contained no reserve in 1926 and has since been designated as a mention of bryophytes. N.G.H. therefore offered to Globally Significant Biodiversity Area and an do some bryophyte work in the forest, in association Important Bird Area (Abu-Juam et al., 2003). It has with A Rocha Ghana, in order to boost the case for long been recognised as a nationally important its protection and to add to the knowledge of the reserve. It is a source of food and water for five Ghanaian bryophyte flora, which is very under- million people, with the headwaters of three major worked. river systems, the Ayensu, Densu and Birim rivers, within its boundaries. These three rivers are the most Bryological history of Atewa Forest and Ghana There have been very few bryophyte surveys in Ghana, Correspondence to: N. G. Hodgetts, 15 Earlish, Portree, Isle of Skye, UK. Email: [email protected] and most of what is known results from the careful © British Bryological Society 2016 DOI 10.1080/03736687.2016.1145525 Journal of Bryology 2016 1 Hodgetts et al. Bryophytes of Atewa Forest, Ghana work of the late Dr Eustace Jones. He visited Atewa below about 600 m) and high altitude (occurring Forest on at least one occasion and made many valu- mainly above about 680 m), the latter also encompass- able records of liverworts, although a visit to the ing areas of swamp forest at lower altitudes. imprecisely localised ‘Kaolin Swamp’ was ‘greatly cur- tailed’ by a thunderstorm and failing light, according Widespread to Jones & Harrington (1983). Jones’s records are A number of common species can be found throughout documented in the same publication. His fieldwork the forest. Lepidozia succida, Fissidens marthae and in Atewa Forest and elsewhere in western Africa also Callicostella africana grow on compacted soil and contributed to his series on African Hepatics, pub- rocks on and next to tracks. Shaded banks, rocks, lished over many years in the Transactions of the dead wood and decaying organic matter support a British Bryological Society and later the Journal of suite of common forest species, notably Leucomium Bryology. Consequently the liverworts of Ghana are strumosum, Pelekium varians, Rhacopilopsis trinitensis, much better documented than the mosses. Wigginton Vesicularia galerulata, Cryptolophocolea martiana, (2009) lists 135 liverwort and hornwort taxa for Radula cf. holstiana, Radulina borbonica, Telaranea Ghana, records largely due to the work of Jones, but nematodes, Lejeunea anisophylla, L. eckloniana, O’Shea (2006) lists only 67 moss taxa. There has Ectropothecium regulare and Isopterygium palmarum. been virtually no bryophyte work in Ghana since Widespread epiphytes include Archilejeunea spp., Jones, apart from a few casual collections by staff Lejeunea anisophylla, L. autoica, L. confusa, L. eck- and visiting academics at the University of Ghana. loniana, Lopholejeunea subfusca, Metzgeria furcata, Plagiochila moenkemeyeri, P. praemorsa, Porotrichum Materials and Methods elongatum, Radula cf. holstiana and Sematophyllum The first author visited Atewa Forest between 10–19 subpinnatum. Species of Neckeropsis are encountered March 2014, together with Jacqueline Kumadoh, occasionally, especially hanging off branches. The Emmanuel Akom and Jeffrey Opoku of A Rocha black greasy-looking patches of Stictolejeunea bal- Ghana and Dr Kweku Essilfie and Anthony Adu- fourii are occasional on tree bases and especially Gyamfi of the Botany Department at the University exposed tree roots. Campylopus savannarum, of Ghana. Local knowledge was used to target areas Groutiella laxotorquata and Cheilolejeunea serpentina of probable high bryophyte diversity, notably streams, are widespread canopy ‘sun epiphytes’. hill summits (where cloud gathers and creates increased Epiphyllous species are mainly a feature of higher humidity) and small areas of swamp forest. However, altitudes, but some of them seem indifferent to alti- coverage was far from comprehensive, and the species tude, although they tend to occur only in more recorded represent no more than the results of targeted humid pockets at lower levels. Cololejeunea obtusifolia, sampling in a very large area of forest. C. pusilla, Leptolejeunea astroidea and Radula flaccida While some of the more common bryophytes were fall into this category. Leptolejeunea astroidea is prob- identified in the field, most taxa were identified later ably the most frequent epiphyllous species in the by N.G.H. from collected specimens. Some specimens forest, but the three other species are also common. Downloaded by [Nick Hodgetts] at 06:20 13 June 2016 were sent to specialists for identification or confir- mation. A wide range of literature was used, but Low-altitude dry forest Wigginton (2004) was a particularly useful tool for The drier parts of the low-altitude forest are not very the identification of liverworts. Specimens have been diverse, supporting a sparse and largely predictable lodged in the Royal Botanic Garden Edinburgh (E), bryophyte flora on the ground and on rocks, dead the herbarium in the Botany Department at the wood, etc., as described above, with the addition of University of Ghana (GC), A Rocha Ghana and the Pelekium gratum, apparently an exclusively low-alti- personal herbarium of N.G.H. tude plant in Atewa Forest. The forest edge is Nomenclature follows Wigginton (2009) for the heavily impacted by human activities, with illegal liverworts and O’Shea (2006) for the mosses, except banana plantations and evidence of mining activities where otherwise indicated. interspersed amongst the natural vegetation. Exposed and insolated