Effects of root competition and soils on seedling establishment at the ecotone between an arid grassland and succulent shrubland in South Africa

2013 ◽  
Vol 25 (2) ◽  
pp. 402-410 ◽  
Author(s):  
Ndafuda N. Shiponeni ◽  
Peter J. Carrick ◽  
Nicky Allsopp ◽  
M. Timm Hoffman
Keyword(s):  
South Africa ◽  
Seedling Establishment ◽  
Root Competition

Germination and development of sown mahogany (Swietenia macrophylla King) in secondary tropical dry forest habitats in Costa Rica

1996 ◽  
Vol 12 (2) ◽  
pp. 275-289 ◽  
Author(s):  
Karin Gerhardt
Keyword(s):  
Costa Rica ◽  
Seedling Establishment ◽  
Rainy Season ◽  
Deciduous Forest ◽  
Secondary Forest ◽  
Dry Forest ◽  
Root Competition ◽  
Evergreen Forest ◽  
Swietenia Macrophylla ◽  
Seedling Mortality

ABSTRACTEffects of irradiance, root competition and water availability on germination and seedling establishment of Swietenia macrophylla King were investigated in tropical secondary dry forests in the Guanacaste Conservation Area, Costa Rica. The fate of seeds sown in the beginning and the middle of the rainy season was studied in abandoned pasture, and in deciduous and semi-evergreen secondary forest. In the pasture, experimental treatments were mown and unmown grass. In the forest sites, thinning to increase light and trenching to reduce root competition were combined in a factorial design. Effects of moisture availability on germination were tested by supplementing natural rainfall in the initial rainy month. Germination at the beginning of the rainy season was not influenced by the supplementary water and was higher in the semi-evergreen forest than in the deciduous forest and pasture. In the forests, germination was little affected by irradiance or root competition. More seeds germinated in unmown than in mown pasture during the initial rains, but were not influenced by mowing when sown in the peak of the rainy season. Seedling mortality was low (>10%) during the initial months, but increased greatly in the dry season. Seedlings germinating early in the rainy season had a higher survival than those germinating later. The relatively slight effects of the different treatments and habitats on seedling establishment suggest that this species is rather insensitive to the large microsite variation in secondary vegetation.

scholarly journals Reproductive potential and seedling establishment of the invasive alien treeSchinus molle(Anacardiaceae) in South Africa

2009 ◽  
Vol 34 (6) ◽  
pp. 678-687 ◽  
Author(s):  
DONALD M. IPONGA ◽  
SUZANNE J. MILTON ◽  
DAVID M. RICHARDSON
Keyword(s):  
South Africa ◽  
Seedling Establishment ◽  
Reproductive Potential

scholarly journals Reproductive potential and seedling establishment of the invasive alien tree Schinus molle (Anacardiaceae) in South Africa

2009 ◽  
Vol 75 (2) ◽  
pp. 406
Author(s):  
D.M. Iponga ◽  
S.J. Milton ◽  
D.M. Richardson
Keyword(s):  
South Africa ◽  
Seedling Establishment ◽  
Reproductive Potential ◽  
Schinus Molle

The Eucalypt Forest Grassland/Grassy Woodland Boundary in Central Tasmania

1992 ◽  
Vol 40 (2) ◽  
pp. 123 ◽  
Author(s):  
RJ Fensham ◽  
JB Kirkpatrick
Keyword(s):  
Seedling Establishment ◽  
Suppressive Effect ◽  
Root Competition ◽  
Detectable Effect ◽  
Tree Seedlings ◽  
Herbicide Application ◽  
Eucalypt Forest ◽  
High Elevations ◽  
Planted Tree ◽  
Primary Agent

Downslope boundaries of forest with grassland and grassy woodland occur over a wide altitudinal range in central Tasmania. Three sites were selected for study of the causes of these boundaries at low, medium and high elevations. The open vegetation was generally associated with moister and less rocky soils and more subdued topography than the adjacent forest. Frost incidence and intensity, soil moisture and waterlogging varied markedly among the three open areas. Planted tree seedlings survived 4 years in the open at all sites, and seedlings established in the open both naturally, and after sowing, where grass competition was reduced by herbicide application, digging or root competition from adult eucalypts. Grazing had no detectable effect on seedling establishment. A pot experiment demonstrated a suppressive effect of native grass swards on both seedling establishment and growth, this effect being largely independent of available moisture and nutrients. While frost, waterlogging, fire and drought may play a role in inhibiting eucalypt establishment and increasing eucalypt mortality at some or all of the sites, the dense grass swards found in all the open areas are considered to be the most likely primary agent of tree exclusion.

Time and Latitude in South Africa

1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers
Keyword(s):  
South Africa ◽  
Cape Town ◽  
Astronomical Observations ◽  
Royal Observatory ◽  
The Republic ◽  
Astronomical Determination ◽  
Limited Accuracy ◽  
Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

Indirect Rule in South Africa

2009 ◽  
Author(s):  
J. C. Myers
Keyword(s):  
South Africa ◽  
Indirect Rule

Combining Professional Interests and Travel: People to People Citizen Ambassador Program

2011 ◽  
Vol 1 (2) ◽  
pp. 47-54
Author(s):  
Alex Johnson ◽  
Amanda Hitchins
Keyword(s):  
South Africa ◽  
Health Education ◽  
Communication Disorders ◽  
Social Conditions ◽  
Speech Language Pathologists ◽  
Exchange Program

Abstract This article summarizes a series of trips sponsored by People to People, a professional exchange program. The trips described in this report were led by the first author of this article and include trips to South Africa, Russia, Vietnam and Cambodia, and Israel. Each of these trips included delegations of 25 to 50 speech-language pathologists and audiologists who participated in professional visits to learn of the health, education, and social conditions in each country. Additionally, opportunities to meet with communication disorders professionals, students, and persons with speech, language, or hearing disabilities were included. People to People, partnered with the American Speech-Language-Hearing Association (ASHA), provides a meaningful and interesting way to learn and travel with colleagues.

Sign in / Sign up

Export Citation Format

Share Document