Mountains of the Mist: A first plant checklist for the Bvumba Mountains, Manica Highlands (Zimbabwe-Mozambique)

The first comprehensive plant checklist for the Bvumba massif, situated in the Manica Highlands along the Zimbabwe-Mozambique border, is presented. Although covering only 276 km2, the flora is rich with 1250 taxa (1127 native taxa and 123 naturalised introductions). There is a high proportion of Orchidaceae and Pteridophyta, with both groups showing a higher richness than for adjacent montane areas, which may be due to the massif’s relatively high moisture levels as a result of frequent cloud cover. However, in contrast to other mesic montane regions in southern Africa, there are relatively few near-endemic or range-restricted taxa: there is only one local endemic, Aeranthes africana, an epiphytic forest orchid. This is likely to be an effect of the massif having limited natural grassland compared to forest, the former being the most endemic-rich habitat in southern African mountains outside of the Fynbos Biome. Six other near-endemic taxa with limited distribution in this portion of the Manica Highlands are highlighted. The high number of invasive species is probably a result of diverse human activities in the area. The main species of concern are Acacia melanoxylon, a tree that is invading grassland and previously cultivated land, the forest herb Hedychium gardnerianum which in places is transforming forest understorey with an adverse effect on some forest birds, and the woody herb Vernonanthura polyanthes which invades cleared forest areas after fire. Future botanical work in the massif should focus on a more detailed exploration of the poorly known Serra Vumba on the Mozambican side and on the drier western slopes. This will allow for a more detailed analysis of patterns of endemism across the Manica Highlands.

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New species and notes on Hesperantha (Iridaceae) in southern Africa

Bothalia ◽

10.4102/abc.v37i2.312 ◽

2007 ◽

Vol 37 (2) ◽

pp. 177-182 ◽

Cited By ~ 9

Author(s):

P. Goldblatt ◽

J. C. Manning

Keyword(s):

New Species ◽

Southern Africa ◽

Field Studies ◽

Eastern Cape ◽

Separate Species ◽

Dwarf Plant ◽

Perianth Tube ◽

Local Endemic ◽

Sub Saharan ◽

Three New Species

Field studies of the sub-Saharan African and largely southern African Hesperantha conducted since 2003 have resulted in the discovery of three new species in this genus, bringing the total to 82. Hesperantha longistyla J.C.Manning Goldblatt. known from one collection from the mountains of SW Namibia, is a dwarf plant with moderately long-tubed, purple flowers and unusually long style branches, possibly allied to the Kamiesberg species, H. latifolia. A second species, H. helmei Goldblatt J.C.Manning, also known from a single collection from the interior mountains of Eastern Cape near Graaff- Reinet, has terete leaves and small flowers with tepals ± 8 x 2.5 mm, about as long as the perianth tube. It is apparently most closely allied to the Roggeveld species, H. cliolata. A third novelty, H. lithicola J.C.Manning Goldblatt. restricted to the Swartruggens range in the eastern Cold Bokkeveld, has bell-shaped corms with toothed margins, leaves 1-2 mm wide, and white flowers with a tube 10-12 mm long, and appears most closely allied to the widespread H. falcata. A new collection of H karooica from northeast of the Hantamsberg represents a small but significant range extension for this local endemic previously known from just two collections near Calvinia, south of these mountains. The flower size, especially dimensions of the tepals, confirms its status as a separate species allied to H. vaginata. Lastly, new collections o f the relatively uncommon, yellow-flowered variant of H. acuta show that this plant, confined to the eastem portion of the range of the species, differs consistently from the white-flowered form in several floral features, and it is raised to subspecies rank as H. acuta subsp. tugwelliae.

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Is the Invasive Species Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae) (Argentine Stem Weevil) a Threat to New Zealand Natural Grassland Ecosystems?

Frontiers in Plant Science ◽

10.3389/fpls.2016.01091 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 2

Author(s):

Barbara I. P. Barratt ◽

Diane M. Barton ◽

Bruce A. Philip ◽

Colin M. Ferguson ◽

Stephen L. Goldson

Keyword(s):

Invasive Species ◽

New Zealand ◽

Grassland Ecosystems ◽

Listronotus Bonariensis ◽

Natural Grassland

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22 Years of Near-zero Cloud Cover Variability across Varying Geographical Landscapes of Southern Africa: A Surprising Anomaly

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i730450 ◽

2021 ◽

pp. 150-163

Author(s):

Mutinta Nkolola

Keyword(s):

Climate Change ◽

Southern Africa ◽

Cloud Cover ◽

Current Knowledge ◽

Physical Geography ◽

Climatic Variables ◽

Climatic Research Unit ◽

Energy Budgets ◽

Gridded Dataset ◽

Diurnal Range

In physical geography, clouds are known to dictate global energy budgets and to have crucial ripple effects on other climatic variables such as diurnal range of temperature (DTR), a key indicator of climate change. Here, a 115-year state-of-the-art station based gridded dataset from the Climatic Research Unit (CRU) is interrogated to understand the evolution of cloud cover across southern Africa for the period 1901 - 2016. Results show near-constant variability from 1901 – 1922. It was therefore hypothesised that the observed near-constant variability would result in a similar pattern for some climatic variables such as DTR as the opposite would bring into question our current knowledge of geographical mechanisms underlying DTR control across the region. Further analyses showed little to no association between cloud cover and other climatological variables (including DTR) for the period 1901 – 1922 but strong and significant association from 1923 – 2016. This is the first observational evidence of near-constant cloud cover variability; it is surprising, and counterintuitive. This constant variation can be attributed to limited ground-based observations that went into the construction of the CRU gridded dataset during the 1901 – 1922 period and therefore, caution needs to be exercised by studies that need to use the data for the said period. This is a crucial area of scientific enquiry, and a lack of caution can lead to misleading conclusions on cloud cover evolution and how that relates to climate change.

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Cyathula prostrata (pasture weed).

10.1079/isc.120116.20203482884 ◽

2020 ◽

Author(s):

Eduardo Ventosa-Febles

Keyword(s):

Invasive Species ◽

Central America ◽

Pacific Islands ◽

Perennial Herb ◽

Secondary Forests ◽

Cultivated Land ◽

Grazing Land

Abstract Cyathula prostrata is an annual to short-lived perennial herb native to Africa and Asia and some parts of Oceania, now found naturalized elsewhere in Oceania and in South and Central America. It grows as a weed in cultivated land, roadsides, grazing land, along seashores and in primary and secondary forests and is classed as an invasive species in a number of Pacific Islands.

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The Resolution and Contrast in Biological Sections Determined by Inelastic and Elastic Scattering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071569 ◽

1973 ◽

Vol 31 ◽

pp. 224-225

Author(s):

D. L. Misell

Keyword(s):

Electron Microscopy ◽

Adverse Effect ◽

Elastic Scattering ◽

Inelastic Scattering ◽

Amorphous Carbon ◽

Polymeric Materials ◽

Chromatic Aberration ◽

Image Resolution ◽

Quantitative Estimates ◽

Elastic Ratio

In the electron microscopy of biological sections the adverse effect of chromatic aberration on image resolution is well known. In this paper calculations are presented for the inelastic and elastic image intensities using a wave-optical formulation. Quantitative estimates of the deterioration in image resolution as a result of chromatic aberration are presented as an alternative to geometric calculations. The predominance of inelastic scattering in the unstained biological and polymeric materials is shown by the inelastic to elastic ratio, I/E, within an objective aperture of 0.005 rad for amorphous carbon of a thickness, t=50nm, typical of biological sections; E=200keV, I/E=16.

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