CO2 climate. International Journal of Climatology 16:1149-1156, 1996.
Reprint : Not in File,
Keywords : DROUGHT; SOUTHERN AFRICA; CLIMATE
Ref ID : 972
1175. Joubert, A.M. and Mason, S.J. Droughts over southern Africa in a doubled-
co2 climate. International Journal of Climatology 16:1149-1156, 1996.
Reprint : In File,
Keywords : DROUGHT; CLIMATE CHANGE; MODELS; RAINFALL
Abstract : The southern African region is susceptible to climatic extremes and
particularly to extended dry periods. Possible changes in the probability of
dry years under doubled-CO2 conditons are examined using output from the CSIRO
nine-level general circulation model. Changes in annual mean rainfall are not
expected to be significant. However, the model simulates an increase in the
probability of dry years in the tropics, to the south-west of the subcontinent,
as well as over the western and eastern parts of SA and southern Mozambique,
where large percentage increases in the the most intense dry spells are
indicated. A decrease in the frequency of dry years is simulated over much of
the interior of the subcontinent south of 10oS. In regions where the frequency
of dry years decreases, the most severe events occur less often. The CSIRO
nine-level model indicates a shift in the frequency distribution of daily
rainfall events under doubled-CO2 conditions. A small change in the frequency
distribution of daily rainfall events may have further implications for the
frequency of mid-summer droughts during the peak summer rainfall period of
December-February. Increases in the frequency of mid-summer droughts are
simulated over the eastern part of the subcontinent south of 20oS.
Ref ID : 993
1176. Joubert, A.M. and Tyson, P.D. Equilibrium and fully coupled GCM
simulations of future southern African climates. South African Journal of
Science 92:471-484, 1996.
Reprint : In File,
Keywords : CLIMATE CHANGE; MODELS; CLIMATE; RAINFALL; SOUTHERN AFRICA
Notes : Changes in seasonally averaged surface air temperature, mean sea-level
pressure and rainfall predicted by a representative range of current equilibrium
climate models linked to mixed-layer oceans and fully coupled ocean-atmosphere
models are compared. All fully coupled and mixed-layer models predict increased
temperatures under enhanced greenhouse conditions throughout southern Africa.
By comparison with the mixed-layer models, the magnitude of warming predicted by
the fully coupled models is much diminished, particularly over the southern
oceans. However, it is important to compare predicted warming normalized to a
global average of 1oC in order to account for differences in experimental design
between fully coupled and mixed-layer models. The pattern of normalized warming
indicates that fully coupled models predict greater warming than the mixed-layer
models over the subcontinental land mass, whereas the mixed-layer models predict
greater normalized warming in the high latitudes of the southern oceans.
Predicted decreases in pressue simulated by both fully coupled and mixed-layer
models over much of the tropics and subtropics are indicative of an
intensification of the tropical easterly circulation. However, caution must be
exercised in using mean sea-level pressures to estimate circulation changes over
the interior plateau region. None the less, the magnitude of predicted changes
in pressure are similar to observed pressure anomalies associated with extended
periods of above- and below-normal rainfall over southern Africa. LIttle
confidence may be expressed in simulated circulation changes over the oceans
south of the subcontinent. Neither the fully coupled nor mixed-layer models
predict any significant change in rainfall seasonality over southern Africa
under enhanced greenhouse conditions. Both types of model simulate 10-20%
increases in rainfall during summer in the tropics. These predicted changes are
physically consistent with predicted increases in temperature and an intensified
tropical easterly circulation. Over much of the rest of the subcontinent, fully
coupled models and to a lesser extent mixed-layer models simulate rainfall
decreases in summer which are not physically consistent with similar changes in
temperature and pressure. However, both types of model display almost no
agreement in the predicted sign of rainfall change over the subcontinent during
the second half of summer. As such, the uncertainties associated with the
simulation of future rainfall changes remain to be resolved and are a major
obstacle to the confident development of future climate scenarios. Recent
evidence suggests that significant errors may exist in current fully coupled
model simulations of the southern ocean. Currently, mixed-layer models may be
more reliable for developing regional climate change scenarios.
Ref ID : 1493
1177. Joubert, E. The past and present distribution and status of the black
rhinoceros Diceros Bicornis Linn 1758 in South West Africa. Madoqua 4(1):33-34,
1971.
Reprint : Not in File,
Keywords : NAMIBIA; FAUNA; STATISTICS
Ref ID : 2245
1178. Joubert, S. Bosindringing en verdigting in Natalstreek. Proceedings of a
workshop on bush encroachment and bush thickening held in Pretoria. Pienaar,
A.J.Anonymous Pretoria:Department of Agriculture and Fisheries. :D1-D5, 1980.
Reprint : Not in File,
Keywords : BUSH ENCROACHMENT
Ref ID : 245
1179. Jurgens, N., Burke, A., Seely, M.K., and Jacobson, K.M. Desert. In:
Vegetation of Southern Africa. edited by Cowling, R.M., Richardson, D.M., and
Pierce, S.M.Cambridge:Cambridge University Press, 1997,p. 189-214.
Reprint : In File,
Keywords : BOTANICAL SURVEY; NAMIBIA; SOUTHERN AFRICA; VEGETATION DYNAMICS
Notes : The author concludes that, although the Namib has been the focus of much
botanical interest, scientific research on the vegetation has been limited.
More research is required on all aspects of the biome's flora and vegetation.
More taxonomic research is still required in a number of taxa, e.g.
Mesembryanthemaceae and various petaloid monocots. Distribution data for species
and vegetation units are also inadequate. Basic knowlede on important
environmental parameters, e.g. fog precipitation, is missing. Very few sites
for the analysis of vegetation dynamics have been established in this highly
variable environment. Little data is available on species interactions, life-
history strategies or soil-plant interactions, and comprehensive ecosystem-level
studies have yet to be initiated. Data is lacking on the history of the desert
environment, especially with respect to changing patterns of human influence.
Studies on desertification processes and the potential for restoring degraded
environments are in their infancy. It would be a great tragedy if the unique
flora and vegetation of the Namib Desert were to remain so poorly known and
understood.
Ref ID : 1001
1180. Jury, M.R. A preliminary note on rainfall and vegetation trends in the
south-western Cape: 1985-1988. South African Journal of Botany 59(2):265-269,
1993.
Reprint : In File,
Keywords : RAINFALL; VEGETATION CHANGE; WESTERN CAPE; CLIMATE; DROUGHT
Abstract : Changes in the distribution of vegetation and rainfall over the
south-western Cape from 1985 to 1988 were analysed. The density of
photosynthetically active biomass was determined from visible satellite imagery
using internationally accepted algorithms. Trends in rainfall were evaluated on
the coastal plain to the south of 33oS and over the elevated interior to the
north of 33oS. During the study period, rainfall exhibited a declincing trend
over the coastal plains. In contrast, the elevated interior experienced a
three-fold increase. In response, photosynthetic activity within the coastal
belt declined, whereas the interior Karoo region was replenished with vegetation
including savanna-type shrubs and grasses. Changes in the distribution of
rainfall and vegetation may be explained by a southward shift of the sub-
tropical and mid-latitude climate zones. Such a shift could become a permanent
feature in a global-warming scenario, and focuses attention on the plight of
marginal agricultural zones in the face of increasing drought and human stress.
Ref ID : 1000
1181. Jury, M.R. and Levey, K. The Eastern Cape drought. Water SA 19(2):133-137,
1993.
Reprint : In File,
Keywords : DROUGHT; EASTERN CAPE; AGRICULTURAL PRODUCTION; NAMIBIA; RAINFALL
Abstract : In recent years the Eastern Cape has experienced recurring drought
with unfavourable impacts on agricultural production and water resources. Dam
levels in early 1992 were 30% of capacity. Statistical analysis has
demonstrated that drought recurs at intervals of 3,45 and 18,2 years,
particularly when March rains fail to materialise. Regional analysis of
cloudiness, surface and upper level winds, and sea surface temperatures exhibit
distinctive patterns in drought years. Low-level winds sweep eastward bringing
Karoo-like conditions to the Eastern Cape, in association with increased jet
stream winds. Reduced cloudiness is noted in a NW-SE band extending from
Namibia across the Eastern Cape watershed. To the south of Madagascar, the SW
Indian Ocean anticyclone strengthens in drought years and increased trade winds
cause the Agulhas Current to cool and recurve soutwards near East London.
Consequently sea surface temperatures to the south-west are 3oC cooler in dry
years. The subtropical humid air mass over the Agulhas Current and north-
eastern South Africa retreates eastwards, and rainfall associated with cut-off
lows and ridging anticyclones is limited over the Eastern Cape.
Ref ID : 853
1182. Kakembo, V. The role of railway culverts in gully development near Alice,
Eastern Cape. Unpublished paper presented to Future research directions in the
Eastern Cape Symposium, Rhodes University. 1995.
Reprint : Not in File,
Keywords : SOIL EROSION; CISKEI; SETTLEMENT IMPACTS
Ref ID : 778
1183. Kakembo, V. A reconstruction of the history of land degradation in
relation to land use change and land tenure in Peddie district, former
Ciskei.Rhodes University, Grahamstown. , 1997. A history of land degradation is
reconstructed in a part of the dividing ridge between the Great Fish and
Keiskamma rivers, in Peddie District, former Ciskei. The study entails a
comparative investigation of the progressive changes in land use, vegetation and
soil erosion in three tenure units, namely: former commerical farms, traditional
and betterment villages. Analysis of the sequential aerial photograph of the
area for 1938, 1954, 1965, 1975 and 1988 is employed. This is backed by
groundtruthing exercises. Data thus obtained is quantified, and linkages
between degradation, anthropogenic and physical factors are derived using
ARC/INFO GIS. Differences in land tenure systems emerge as the main controlling
factor to variations in land degradation. Confinement of vegetation diminution
and erosion to traditional and betterment villages is observed at all dates.
Scantily vegetated surfaces and riparian vegetation removal are a characteristic
feature of both areas throughout the study period. 'Betterment', introduced in
the early 1960s to curb land degradation is, instead, observed to exacerbate it,
particularly soil erosion. Trends in land use change are characterised by the
abandonment of cultivated land, which is noted to coincide with a sharp rise in
population. Erosion intensification into severe forms particularly between 1965
and 1975, coincident with a period of extreme rainfall events, emerges as the
most significant degradation trend. A close spatial correlation between
abandoned cultivated land and intricate gullies is identified. So is the case
between grazing land and severe sheet erosion. Within the grazing lands, an
examination of erosion and categories of vegetated surfaces reveals that erosion
occurs predominantly on the scanty vegetation category. Such erosion-vegetation
interaction largely explains the non-recovery of the scanty vegetation category,
even during periods of intense rainfall. Extensive channel degradation is
evident along stream courses with scant riparian vegetation. Physical factors
are noted to have a significant bearing on erosion. The high prevalence of
erosion on the Ecca group of rocks confirms its erosion-prone nature. Pockets
of colluvium and alluvium accumulation in the steep bottomlands are identified
as the sites of the most severe gully erosion. Field surveys at some of the
sites indicate that a dolerite sill through the area forms a boundary of
colluvium accumulation and the upslope limit to gully incision. That these
sites are recognised as formerly cultivated land, portrays the interaction
between physical and anthropogenic variables with regard to inducing degradation
in the area.Master of Science.
Reprint : Not in File,
Keywords : LAND DEGRADATION; BETTERMENT PLANNING; LAND USE; COMMUNAL AREA;
CISKEI; SOIL EROSION; EROSION; LAND TENURE; POPULATION; RAINFALL
Notes : Abstract in file.
Ref ID : 1067
1184. Kakembo, V. Land degradation in relation to land tenure in Peddie
District, Eastern Cape. In: Proceedings of the international conference on land
tenure in the developing world with a focus on Southern Africa, held at the
University of Cape Town, 27-29 January 1998, edited by Barry, M.Cape
Town:Department of Geomatics, University of Cape Town, 1998,p. 311-318.
Reprint : In File,
Keywords : LAND DEGRADATION; LAND TENURE; CISKEI; COMMUNAL AREA; EASTERN CAPE;
SOUTHERN AFRICA; SOIL EROSION; EROSION; LAND REFORM; RESTORATION; CONSERVATION;
POLICY
Abstract : A study of land degradation is carried out in part of Peddie
district, Eastern Cape. It entails a comparative investigation of the
progressive changes in vegetation and soil erosion in three adjacent land tenure
units, namely: former commercial farms, traditional and betterment villages.
Sequential aerial photographs of the area for 1938, 1954, 1965, 1975 and 1988
are analysed. Data thus obtained is quantified and analysed using PC ARC/INFO
GIS. Differences in land tenure emerge as the main controlling factor to
variations in land degradation. Vegetation diminution and soil erosion are
confined to both traditional and betterment villages at all the dates.
"Betterment", introduced in the early 1960s to curb land degradation is instead,
observed to exacerbate it. The implications of these findings for land reform,
restoration and conservation policy directions are crucial.
Ref ID : 530
1185. Kalipeni, E. Population growth and environmental degradation in southern
Africa, Boulder, Colorado:Rienner, 1998.
Reprint : Not in File,
Keywords : POPULATION; LAND DEGRADATION; SOUTHERN AFRICA
Ref ID : 2406
1186. Kalule-Sabiti, J. and Kahimbaara, J.A. Analysis of life time migration in
the former Transkei, Eastern Cape. South African Journal of Sociology , 1990.
Reprint : Not in File,
Keywords : TRANSKEI; EASTERN CAPE; POPULATION; CARRYING CAPACITY; LABOUR;
MONITORING; RURAL DEVELOPMENT; SOCIOECONOMIC ASPECTS
Notes : The purpose was to provide data on internal migration in Transkei in
order to fill a gap that has been identified. Issues such as trends and
patterns of internal migration, including migration fields of the sample urban
places at varying stages in the migration cycle, characteristics of the
migration process, reasons for migrating and similar issues were addressed. A
questionnaire consisting of three parts was used for the study. These were:
the household schedule to obtain information from all members of each household,
the migration schedule to collect information on the characteristics of
migrants, and a rural link schedule to establish the perception of migrants
regarding their perforamnce in their destinations. A stratified sampling
procedure was used, and a sample size of 3223 households was used. It was found
that one major sending area of migrants to the main Transkei urban centres was
the Republic of South Africa, thus giving the migration pattern a regional
dimension. The regional nature of migration in the Transkei implies a high rate
of population growth relative to the carrying capacity of the territory. The
agricultural sector cannot adquately support the population; more in-migration
can only worsen the situation. Another major sending area of migrants was a
combination of other places in Transkei. There is considerable internal
migration mainly from rural to urban areas. This implies a relatively rapid
growth of urban areas and a decline in the labour force of the rural areas. A
recommended solution to increase pressure on the resources of Transkei arising
from migration, is to adopt development programmes that would increase economic
productivity in the territory. This article is obtainable from the UFH main
library. See ref. I.D. no: 2339.
Ref ID : 2466
1187. Kaniki, A.M. Exploratory study of information needs in the Kwa-Ngwanase
(Natal) and Qumbu (Transkei) communities in South Africa. South African Journal
of Library and Information Science , 1994.
Reprint : Not in File,
Keywords : TRANSKEI; AID; DROUGHT; POVERTY; KWAZULU NATAL; RURAL DEVELOPMENT;
ECONOMIC ASPECTS; SUBSIDIES
Notes : The purpose was to investigate the information needs of rural persons in
Kwa-Ngwanase and Qumbu, who the information providers are, demographic
distributions of persons within the communities and implications and relevance
of the demographic data in relation to the information needs and the information
providers. The choice of communities for this study was somewhat accidental but
convenient. In each of the communities 100 persons were selected randomly and
an interview was conducted using structured questionnaires. In total 200 persons
were interviewed. Data were collected on critical incidents of information
seeking situations, various information providers and demographic data on
respondents. The findings revlealed that the two rural communities in South
Africa experienced a variety of information needs. Most persons in the
communities experienced problems of getting information on employment
opportunities, information on financial aid for education, information on
agricultural marketing facilities and services for products, information on
drought, pest control and eradication, poverty in the area etc. In general, the
study attempted to answer the following questions: what are the information
needs in the two communities? Which information providers do people use? And
what is the demographic distribution of each community and its implication for
the information provision in these areas. This article is obtainable from the
main library at the University of Fort Hare. See also ID ref. no. 2339.
Ref ID : 168
1188. Kanthack, F.E. The alleged desiccation of South Africa. The Geographical
Journal 76(6):516-521, 1930.
Reprint : In File,
Keywords : DESSICATION; HYDROMETEOROLOGY; DROUGHT; ENVIRONMENTAL HISTORY;
EROSION; SOIL EROSION; RAINFALL; CONSERVATION; POVERTY
Notes : There is a common perception, which grows in times of drought, that SA
is drying up. Another aspect which excites both public and official imagination
is that erosion of the soil and softer rocks of the country has been proceeding
on an enormous scale during the past hundred years. So far as the public and
farmers are concerned, these two aspects are generally linked and devastation of
large areas due to soil erosion is attributed to meteorological changes during
the past century. In dealing with these problems, this paper defines what is
meant by dessication. The author suggests that, while these problems exist, in
arid and semi-arid areas there is little evidence to support the contention that
conditions have materially changed since the advent of the white man in SA. The
contention that rainfall has dropped dramatically is also dealt with. Instead,
the author suggests other factors which may have influenced soil degradation,
such as faulty farming. He concludes by saying that a vast tonnage of excellent
soil has during the past century been sent down to the ocean to swell the
dimensions of the great Agulhas bank and is, of course, irretrievably lost, and
it would take thousands of years to make good the damage by natural means if all
further erosion were stopped. Much can however be done to check the rate of
destruction. The better type of farmer - pastoral or agricultural - has been
doing excellent work for many years, and he is well aware that conservation of
the veld and of his valuable alluvial soils is a paying proposition and that
failure to do so means bancruptcy. The arid and semi-arid back-veld is however
still mainly inhabited by ignorant, poverty stricken, and indolent people who
are difficult to educate, unwilling to learn, incapable of carrying out
improvements because of their poverty, and often very work-shy. There is at the
moment a recrudescence of official concern about the alarming effects of soil
erosion following seven years of indifference and inactivity since the Drought
Commission report was published, and it is to be hoped that something tangible
will result.
Ref ID : 2033
1189. Keet, J.D.M. Tree planting in Orange Free State, Griqualand West,
Bechuanaland, and north-eastern districts of the Cape Province.Anonymous
Pretoria:Department of Forestry. 24, 1929.
Reprint : Not in File,
Keywords : FREE STATE; FORESTRY
Notes : Bulletin no 24 of the Department of Forestry, Pretoria.
Ref ID : 2034
1190. Keet, J.D.M. Report on drift sands in South Africa.Anonymous
Pretoria:Department of Agriculture and Forestry. 9, 1936.
Reprint : Not in File,
Keywords : FORESTRY
Notes : Forestry Series no. 9, Department of Agriculture and Forestry, Pretoria.
Ref ID : 459
1191. Kelbe, B., Mulder, G., Bodenstein, B., Hattingh, D., and Verwey, A. An
investigation of the hydrological response to third world settlements in peri-
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