frequency of less than 5% will require in excess of 1200 points to achieve a 20%
precision.
Ref ID : 1652
903. Fabricius, C. and Burger, M. Biodiversity change and ecological hierarchies
in response to land management in Xeric Succulent Thicket: The bigger
picture.Anonymous Port Elizabeth:Eastern Cape Nature Conservation. :1-18, 1996.
Ecosystems are driven by processes which operate at the landscape, land element,
producer community and consumer community levels. Landscapes in Xeric Succulent
Thicket consist of land elelments (bushclumps) which act as resource patches for
plants and animals. These patches are reduced in size and complexity as the
intensity of herbivory increases. Current understanding of biodiversity and
ecosystem functioning postulates that ecosystems degrade according to an
integrated process of reduction in patch productivity and within-patch
heterogeneity. This leads to a decrease in within-patch species richness, and
an increase in nutrient and energy flow from resource patches into the
surrounding matrix. In smaller patches, palatable plants are exposed to
herbivory, and good light competitors are outcompeted by good colonizers. This
further reduces diversity. At the landscape level, landscape complexity is
reduced through a decrease in the variety of patch types across the landscape
and a reduction in species turnover between patches. Landscapes dominated by
small patches are subject to perpetual 'drought' conditions. Arthropod species
richness and abundance decreases because of the harsher and more simplified
environment, which leads to more severe species interactions and the
simplification of trophic and other ecosystem webs. Regression analysis of
plant species richness on land element diversity, and arthropod species richness
on plant species richness corroborates this paradigm: increasing levels of
herbivory leads to a successive loss of species. As the spatial heterogeneity
in the environment decreases, species become rarer and recruitment eventually
ceases. Weevils are especially well correlated with the diversity of other
ecosystem elements higher up the hierarchy. Snakes and lizards recognized
different resource patches because of their ectothermic physiology - their
resource patches are interclump areas where heat is abundant and where hunting
success is high. They flourish in the degraded areas, especially since avian
and mammalian predators are scarce in such landscapes. Biodiversity at the
ecosystem, landscape and community levels in Xeric Succulent Thicket is severely
affected by herbivory, primarily because of its influence on bushclump size.
The maintenance of large bushclumps is the key to the successful preservation of
biodiversity at the landscape and sub-landscape levels in Xeric Succulent
Thicket.
Reprint : In File,
Keywords : BIODIVERSITY; LAND USE; COMMUNAL AREA; GRAZING EFFECTS; PLANT-ANIMAL
INTERACTIONS; VEGETATION CHANGE; VEGETATION DYNAMICS; VELD CONDITION; EASTERN
CAPE; ENERGY; DROUGHT; SUCCULENT KAROO; PRODUCTION POTENTIAL; SOIL NUTRIENTS;
ENVIRONMENTAL HISTORY; ANIMAL PHYSIOLOGY
Ref ID : 1752
904. Fabricius, C. and Burger, M. Comparison between a nature reserve and
adjacent communal land in Xeric Succulent Thicket: an indigenous plant user's
perspective. South African Journal of Science 93:259-262, 1997.
Reprint : In File,
Keywords : NATURE RESERVES; CISKEI; EASTERN CAPE; COMMUNAL AREA; AID;
CONSERVATION; CULTIVATION; MONITORING; SUCCULENT KAROO; VELD MANAGEMENT;
SOCIOECONOMIC ASPECTS; BIODIVERSITY; ENERGY; STATISTICS
Abstract : Local people with knowledge of indigenous plants could constribute to
the management of protected areas while simultaneously improving their options
for employment. Members of a local Xhosa community who lived adjacent to the
Great Fish River nature reserve in the former Ciskei, Eastern Cape, were
employed to assist us with an inventory of locally useful plants. The survey
was designed to quantify differences in plant diversity between the nature
reserve and the adjacent communal area, from the point of view of indigenous
plant users. Tranditional healers and rural villagers who were experienced
users of indigenous plants were recruited with the aid of a community
organisation. Plants which were used for physical and spiritual healing, fuel,
food and construction were identified along paired transects in the nature
reserve and the communal area respectively. Hierarchical richness indices
(HRIs) and the number of recognisable plants as well as their abundance at each
site were used to compare the nature reserve to the communal area. Altogether,
122 utilised plant types were recorded, of which 68% had medicinal or spiritual
value, 12% were used for food, 13% for fuel and 7% for building purposes. These
ratios were similar for both the nature reserve and the communal area. One
hundred and eight (108) useful types of plants were recorded on the nature
reserve and 97 in the communal area. The nature reserve contained 25 'unique'
recognizable plants which were not recorded in the communal area, whereas the
communal area contained 14. Useful plants were more abundant on the nature
reserve than in the communal area, and the average HRI for the nature reserve
was almost double that of the communal area. The advantages to the community
were limited: temporary employment was created and local skills were developed
which might have improved the people's prospects for future employment. The
conservation benefits were more substantial: information became available which
would otherwise have remained hidden, relations between the community and
conservation agencies improved, and credible education programmes in sustainable
resource use could be developed through a participatory approach. The next step
from a management point of view is to provide opportunities for the community to
interpret and apply the results, and with the local people, to explore small
business opportunities based on the cultivation of useful plants. Participatory
research and monitoring could be furthered by putting greater emphasis on the
participatory process than on results, by actively involving local people in the
development of monitoring programmes from the outset, and by interpreting and
deliberating the results of monitoring with them in an interactive way.
Ref ID : 1651
905. Fabricius, C., Burger, M., Allsopp, N., and Gerber, G. Impacts of land use
on the diversity of Xeric Succulent Thicket vegetation: blame it on the
bushclumps.Anonymous Port Elizabeth:Eastern Cape Nature Conservation. :1-17,
1996. This study assesses the influence of domestic herbivores and consumptive
use by humans on the size, species richness and floristics of bushclumps in
Xeric Succulent Thicket in the Eastern Cape Province, South Africa. The
vegetation structure and diversity of a commercial farm and a communal area were
compared to the vegetation of a nature reserve, using paired transects inside
and outside the nature reserve. Pairs of transects were situated close together
on opposite sides of the nature reserve boundary. The percentage cover of the
most palatable shrub species, Portulacaria afra and Grewia robusta was estimated
in a sample of bushclumps at each respective locality as an index of range
condition. An index of bushclump area was obtained by multiplying the longest
axis of a clump by the widest part of the clump perpendicular to the first axis,
i.e. each clump was placed in an imaginary rectangle. The line intercept method
was used to determine the clump:interclump ratios in 10 transects of 500 m at
each locality. The woody and herbaceous species in each clump were recorded,
and the number of species was related to bushclump area. 1. The number of
species in clumps significantly correlated with bushclump area and the
relationship was exponential. 2. The nature reserve had significantly larger
bushclumps than adjacent unconserved land. 3. The nature reserve contained
significantly more species per clump than both the commercial and communal
rangeland. 4. The proportions of sampling lines in the nature reserve which
were intercepted by bushclumps, relative to the total length of the line, were
significantly larger than that of unprotected land. 5. The percentage cover of
P. afra in buschclumps was significantly higher in the nature reserve than on
unconserved land and confirmed the anticipated degradation gradient. The
percentage cover of G. robusta was significantly higher in the nature reserve
than in the communal area, but not significantly higher than on the commercial
farm. 6. Large clumps were characterized by bird-dispersed plant species, while
the species which were not bird dispersed showed no significant association with
any type of clump. 7. Microsites in areas outside bushclumps contained
significantly fewer mycorrhizal spores and less organic material, and very high
aluminium concentrations compared to sites inside clumps. Microsites outside
clumps seemed to be unsuitable for the establishment of seedlings. The
underlying cause of degradation is postulated to be a reduction in bushclump
size through overgrazing and human use, which leads to a decrease in nurse sites
for seedlings of bird-dispersed plants and a gradual extinction of bird-
dispersed trees and shrubs, together with other species associated with clump
interiors. Xeric Succulent Thicket has an extremely low sustainable stocking
rate, whether in a pristine or degraded state. The profit-making phase is the
transient period between a well-conserved and degraded condition: there is no
evidence that the vegetation reverts to its former state after this shift has
taken place. For conservation purposes, the size of bushclumps which exceed 5
m2. This was the inflection point below which species richness in bushclumps
decreased rapidly. To maintain Xeric Succulent Thicket outside protected areas,
farm incomes should be supplemented by land uses other than commercial livestock
production. These include nature tourism, stud farming or low-intensity
commodity farming, e.g. feedlots and medicinal plants.
Reprint : In File,
Keywords : LAND USE; BIODIVERSITY; COMMUNAL AREA; PLANT-ANIMAL INTERACTIONS;
CONSERVATION; GRAZING EFFECTS; EASTERN CAPE; VEGETATION CHANGE; NATURE RESERVES;
STOCKING RATE; LIVESTOCK PRODUCTION; SUCCULENT KAROO; VELD CONDITION
Ref ID : 2501
906. Faculty of Agriculture and ARDRI Qamata Irrigation Scheme: Report.
Commission of enquiry review report.Anonymous , 1996.
Reprint : Not in File,
Keywords : IRRIGATION; SOIL EROSION; EROSION; CISKEI; AGRICULTURAL PRODUCTION;
LAND REFORM; ECONOMIC ASPECTS
Notes : The purpose of the report was to examine the status of Qamata Irrigation
Scheme and to assess its future sustainability. A descriptive survey method was
used. An interview schedule was prepared and participants, landholders and
farmers at the scheme were asked to respond to specific questions. Also, free
for all discussions were held with farmers on the schemes with the aim of
getting their viewpoints and to share ideas on terms of reference. There are
major constraints and challenges affecting agricultural production and progress
at Qamata Irrigation Scheme. The distribution of water within the scheme is
problematic for several reasons. The weir, main canal and leidams are subject
to the effect of soil erosion, which is a major environmental problem at Qamata.
Field canals and associated equipment are in poor condition. Generally surface
irrigation requires careful land preparation. Farming households in Qmata are
extremely poor. The scheme was found not to have addressed the need for markets
by small-scale producers. There was a general absence of information in the
scheme, which inhibits commercially oriented agricultural decision-making. This
report is obtainable from the Ministry, Department of Agriculture, Bisho. See
also ID ref. no. 2339.
Ref ID : 2500
907. Faculty of Agriculture and ARDRI Ncora Irrigation Scheme.Anonymous ARDRI. ,
1996.
Reprint : Not in File,
Keywords : IRRIGATION; TRANSKEI; GOVERNMENT INITIATIVES; ECONOMIC ASPECTS
Notes : The purpose of the study was to investigate and report the present
situation at the Ncora Irrigation Scheme and to further suggest and map out
clear guidelines that government must follow in order to revive the Ncora
Irrigation Scheme. Information was gathered through field surveys and secondary
sources of information. The report contains information on the general overview
of Cofimvaba District and the description of the Ncora Irrigation Scheme, an
analysis of the present situation at the Scheme, the financial assessment of the
scheme. Information on the general assessment of the scheme, solutions to the
problems at the scheme and recommendations for the transformation of the Ncora
Irrigation Scheme are also contained in the report. The report is obtainable
from ARDRI, at the university of Fort Hare. See ID ref. no. 2339.
Ref ID : 1426
908. Fair, T.J.D. The Surplus People: forced removals in South Africa. J.C.A.S
6(1/2):228-231, 1987.
Reprint : In File,
Notes : This book concentrates on events in the 1970s and later, and is regarded
by the authors as an up-date of conditions described in Cosmos Desmond's The
Discarded People, published in 1970. A five-volume report appeared in 1983.
The present book aims to reach a wider audience - that is, literate people in
the areas investigated, community workers, and concerned outsiders. The aim is
more than simply the spreading of information. It is to "contribute to and
expand the campaign against forced removals". However this book is viewed, one
is left to wonder what has been the impact that twenty years of relocation have
had upon those who have directly experienced removals -acceptance, resignation
or deep resentment.
Ref ID : 1099
909. Farrington, J. Organisational roles in farmer participatory research and
extension: lessons from the last decade. Natural resource perspectives, number
27.Anonymous Farrington J. London:Overseas Development Institute (ODI). :1-4,
1998.
Reprint : In File,
Keywords : AGRICULTURAL EXTENSION
Notes : Experience over the last decade suggests that participatory approaches
to technical change are falling into two broad camps: public sector approaches
are generally part of a client orientation strategy and rarely aim to do more
than enhance the functions of technology design and delivery. By contrast, NGO
approaches generally aim for the empowerment of weaker groups. This paper
reviews the complementarities and tensions between the approaches, and suggests
ways forward.
Ref ID : 1006
910. February, E.C. Archaeological charcoals as indicators of vegetation change
and human fuel choice in the late Holocene at Elands Bay, Western Cape Province,
South Africa. Journal of Archaeological Science 19:347-354, 1992.
Reprint : In File,
Keywords : ARCHAEOLOGY; VEGETATION CHANGE; PALAEOENVIRONMENTS; ENERGY; CLIMATE
CHANGE; ENVIRONMENTAL HISTORY
Abstract : Methods used in the analysis of 1163 pieces of charcoal from Elands
Bay, SA, are described. Results from three archaeological sites (Tortoise Cave,
Spring Cave and Mike Taylors Midden) show that the most common woody species at
Elands Bay today also occurred in the archaeological record over the last 4000
years. This would suggest that climatic change over the last 4000 years has not
been sufficient to influence the species composition of wood brought into the
sites by people. There are, however, differences in species composition of
charcoal from Tortoise Cave on the one hand and Mike Taylors Midden (MTM) and
Spring Cave on the other. These differences reflect fundamental differences in
environment between the sites.
Ref ID : 1005
911. February, E.C. Rainfall reconstruction using wood charcoal from two
archaeological sites in South Africa. Quaternary Research 42:100-107, 1994.
Reprint : In File,
Keywords : RAINFALL; ARCHAEOLOGY; PALAEOENVIRONMENTS; CLIMATE CHANGE;
ENVIRONMENTAL HISTORY; CLIMATE
Abstract : Major components of most southern African archaeological sites are
stone, bone and charcoal. A new technique for climate reconstruction utilizes
measurements of vessel size and frequency in the cross-sectional xylem anatomy
of archaeological charcoal from Collingham Shelter and Mhlwazini Cave in the
Natal Drakensberg. Previous wood anatomical studies have shown that links exist
among vessel diameter, vessel frequency and climate. The present study
demonstrates that in relation to rainfall, vessel diameter in the species Protea
caffra and Protea roupelliae correlated positively, whereas vessel frequency
correlated negatively. In P.roupelliae, mean vessel diameter increases from 46
to 62 micrometres along a rainfall gradient ranging frm 760 to 1665 mm. The
signficiant correlations between rainfall and tangential vessel diameter for a
charred sample of P. roupelliae suggest that such measures on an archaeological
charcoal sample may be used to reconstruct rainfall patterns through time.
Using nine assemblages of archaeolgoical charcoal, generalized patterns of
wetter and drier periods can be postulated. Comparison with contemporary values
indicates that at 200 and 2400 yr. B.P. the area near the archaeological sites
was wetter than at present. A dry phase occurred between 1300 and 300 yr B.P.
Values for the contemporary wood sample are the lowest observed, indicating that
present conditions are much drier than those at any time within the last ca.
2000 yr. Dating resolution however, is insufficent to allow more-detailed
interpretation of rainfall conditions over the past 2000 yr.
Ref ID : 1007
912. February, E.C. and Van der Merwe, N.J. Stable carbon isotope ratios of wood
charcoal during the past 4 000 years: anthropogenic and climatic influences.
South African Journal of Science 88:291-292, 1992.
Reprint : In File,
Keywords : CLIMATE CHANGE; PALAEOENVIRONMENTS; VEGETATION CHANGE; ARCHAEOLOGY;
ENVIRONMENTAL HISTORY; CLIMATE
Notes : The principal goal of this paper is to demonstrate the potential for
using 13C/12C ratios (delta C 13) of wood charcoal from archaeological sites as
a climate indicator. An important aspect of this is the need to determine, and
thus exclude, the extent of the anthropogenic CO2 contribution to delta C 13
values. It was concluded that changes in delta C 13 values of the charcoal from
archaeological sites through time are probably due to variations in
precipitation.
Ref ID : 592
913. Feely, J.M. Did Iron Age man have a role in the history of Zululand's
wilderness landscapes? South African Journal of Science 76:150-152, 1980.
Reprint : In File,
Keywords : PALAEOENVIRONMENTS; ARCHAEOLOGY; ENVIRONMENTAL HISTORY; VEGETATION
CHANGE; LAND USE; HYDROLOGY; SAVANNA
Notes : Recent archaeological research on Iron Age man in the Natal lowlands
indicates his presence there for not less than 1600 years. Land-use by such
people for so long may have extensively altered the original vegetation.
Wilderness landscapes in the Zululand wildlife sanctuaries - all low lying and
containing Iron Age sites - may therefore be, at least partly, anthropogenic.
Some implications of this possibility for biogeography, hydrology and the
management of sanctuaries are indicated. There is a prima facie case for
research on lowland 'savannas' to determine to what extent an open tree canopy,
a luxuriant grass layer, and also scrub-encroachment are the result of past
interference by Iron Age man. This applies not only in Natal but also in the
Transvaal lowveld.
Ref ID : 887
914. Feely, J.M. Smelting in the Iron Age of Transkei. South African Journal of
Science 81:10-11, 1985.
Reprint : In File,
Keywords : ARCHAEOLOGY; DEFORESTATION; TRANSKEI; ENVIRONMENTAL HISTORY; CISKEI
Notes : During an initial period of archaeological and ecological reconnaissance
in 1983 for a project to investigate the influence of pre-colonial farming upon
the econology of Transkei, four Iron Age sites (3042, 3054, 3062 and 3075)
contained artefacts inconclusively suggesting smelting. The significance of
these discoveries lies in the fact that published historical and archaeological
evidence up to this time for the smelting of any metal in Transkei and Ciskei is
almost entirely negative.
Ref ID : 1704
915. Feely, J.M. The distribution of iron age farming settlement in Transkei:
470 to 1870.University of Natal. , 1986. Three-quarters of Trankei is covered by
grassland, most of which is thought by many botanists to be secondary to forest
destruction by Bantu speaking farmers. But, the archaeological and
historiographic evidence for farming settlement elsewhere in southern and
eastern Africa, suggests that comparable 'secondary' grassland was probably
distributed much as it is at present, at the time of the earliest farming
settlements (dated to about 1 750 BP). Evidence to test these alternative
hypotheses in Transkei was indirect, incomplete, and confined almost entirely to
the shoreline of the Indian Ocean. Therefore, a project whose main objective was
to determine the probable spatiotemporal distribution of farming settlement in
Transkei prior to 1870, was initiated by Prof. J.E. Granger, Department of
Botany, University of Transkei. A stratified random sampling procedure was
developed, based upon the experience of archaeological surveys elsewhere.
Representative transects were selected to include proportionately the major
physical variables below 1 800m a.s.l. in an area of some 40 000 km2. Most of
these variables are presently aligned approximately parallel to the coastline.
Consequently, transects were aligned from the ocean shoreline to Transkei's
inland boundary, across three of the largest river drainage basins in the north,
centre and south of Transkei. In these transcects twelve disjunct study areas
400 - 1 400 km2 were defined. Within each study area, sample units
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