Coastal dry forests in northern Mozambique

Abstract

Background and aims -The Coastal Forests of Eastern Africa, stretching along the Indian Ocean coastline from Somalia to Mozambique, are considered by Conservation International to be a global biodiversity hotspot -an area of high diversity and endemism under increasing threat. Although the largest remaining extent of these forests is reported to be found in Mozambique, very little is known on their extent, condition and composition here. In addition, the term 'coastal forest' has been used in different ways by different authors. This paper defines and characterises coastal dry forests found in northern Mozambique and assesses their present extent, botanical composition, conservation importance and the threats to these forests. Methods -The study area of 18,150 km 2 lies in Cabo Delgado Province in north-east Mozambique, adjacent to Tanzania. Its limits are determined primarily by geological substrate and landform. Four smaller study sites were chosen covering a range of landforms. Manual interpretation of satellite imagery dating from 1999-2002 was used to calculate possible previous and present extent of 'dense vegetation'. Extensive field collecting was used in determining botanical composition and distribution patterns. IUCN Red List assessments were carried out on selected species using distributional criteria. Results -Dry forests similar to those in southern Tanzania are found widely scattered across coastal Cabo Delgado, sitting in a matrix of miombo woodland and other vegetation types. However, forest cover is not as extensive was believed. We calculate that the original extent of 'dense vegetation cover', which includes coastal dry forest, was 6087 km 2 . Owing to clearance over the last 150 years this is now only 1182 km 2 , of which perhaps only 400 km 2 is moderately-intact dry forest. In this southern part of their range such forests are essentially dry, not moist and mesic, and dominated by a high proportion of deciduous or sclerophyllous evergreen trees. The plant species composition differs significantly from that of the surrounding woodlands. There is a marked change in species composition between forest patches along the coast, and they contain numerous species with restricted global distribution. Since 2003, 68 species new to Mozambique have been recorded from Cabo Delgado in addition to 36 possible new species. Many new records are of species previously only known from south-eastern Tanzania. Previously recorded patterns of restricted distribution and high species turnover between forest patches in Kenya and Tanzania are confirmed. Seven coastal forest species were assessed as Endangered. Regional context and conservation -Coastal dry forests are discussed in relation to the more widespread 'sand forests' of the continental interior of south-central Africa, and shown to have similarities in ecology, species composition, soils and ecology. Very little of the present extent of coastal forests in Mozambique lies within protected areas. The threats to their continued existence in the face of explo...

Ochna dolicharthros (Ochnaceae): a new species from northern Mozambique

“…The coastal lowlands of northern Mozambique form part of the "Coastal Forests of East Africa Ecoregion", an area which is recognised by the World Wildlife Fund and Conservation International as a biodiversity hotspot of global conservation priority (Burgess et al 2004;Timberlake et al 2011). This area was formerly included by White (1983) within his ZanzibarInhambane Regional Mosaic, however more recently these coastal lowlands from southern Somalia to northern Mozambique are now recognised as the Swahelian Regional Centre of Endemism, a phytogeographical area described on the basis of its species richness and endemism (Clarke 1998).…”

Cola dorrii sp. nov. (Sterculiaceae), a threatened Maputaland Forest endemic of South Africa

“…Examples occur in coastal Cabinda to Gabon (Cheek et al 2014;Gosline et al 2014); in coastal northern Mozambique (Timberlake et al 2011 andJohnson et al 2017) and in North West Madagascar (Stirton & DuPuy 1992). PHENOLOGY.…”

Revised treatment of Mozambican Memecylon (Melastomataceae—Olisbeoideae), with descriptions of four new species in M. section Buxifolia

“…Conservation status:-Memecylon aenigmaticum is known from a single location with an area of occupancy (AOO) of 4 km 2 (assuming a 4 km 2 grid cell size). Coastal forests in Cabo Delgado are virtually unprotected, and those in the Quiterajo vicinity are threatened by clearing for subsistence agriculture, logging of large timber trees and cutting of poles, and uncontrolled fires (Timberlake 2009, Timberlake et al 2011. Memecylon aenigmaticum is thus provisionally assessed as Critically Endangered [CR B2ab(iii)] according to the IUCN Red List Categories and Criteria (IUCN 2012).…”

“…Ongoing threats in the Namacubi Forest include continued clearing for subsistence agriculture, cutting of poles, uncontrolled fires, and possible road construction for oil-and-gas development which would increase access to and clearing of the forest (Timberlake et al 2011, Cheek & Darbyshire 2014.…”