Bibliography: Land Degradation in South Africa project



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HISTORY; SOUTHERN AFRICA; FOREST; SAVANNA; GRASSLAND; FYNBOS; CLIMATE; NORTHERN

CAPE


Abstract : Late Quarternary pollen sequences representing various sediment types

like spring, lake, swamp, cave and dung deposits, have been studied in southern

Africa. There is evidence for both expansion and reduction of woody vegetation

in different parts of the region before 25 000 BP, but these changes are

difficult to date precisely. There are indications of a depression of

vegetation belts after 25 000 BP in the eastern tropical parts of the sub-

continent, in which forests and savannas were replaced by cool, sub-humid,

upland grasslands. In the south-eastern upland grassland area, humid, cool

conditions with fynbos and swamps developed ca. 23 000 BP and this also implies

downward displacement of vegetation. A period of relative dryness is suggested

south of the Limpopo during the coldest times ca. 20 000 to 18 000 BP. Before

13 000 BP, wet conditions returned to this region. Weaker seasonal

distributions of climate may explain spreading of some small Compositae shrubs

during the end of the Pleistocene and early Holocene in the northern Cape and

Karoo regions. Several places show dry conditions ca. 8 000 BP, followed by

progressively more moist climates, peaking soon after the development of a

temperature optimum ca. 6 500 BP. Slightly cooler conditions followed during

the later Holocene. Good grass cover persisted in the southern highveld and

Karoo, until ca. 1 200 BP, and was followed by slightly unfavourable conditions,

ca. 1000 - 820 BP. Grassy vegetation occurred in upland Karoo areas until ca.

300 BP, and during the last 150 years, modern stock farming practices led to the

spread of more shrubby vegetation.

Ref ID : 1437

1788. Scott, L. Palynological evidence for late Quaternary warming episodes in

Southern Africa. Paleogeography, Paleoclimatology, Paleoecology 101:229-235,

1993.


Reprint : In File,

Keywords : SOUTHERN AFRICA; GRASSLAND; SAVANNA; RAINFALL; VEGETATION CHANGE;

CLIMATE CHANGE; CLIMATE; KAROO DESERTIFICATION

Abstract : Polleniferous sediments from southern Africa associated with past

warm episodes before the Last Glacial Maximum, are rare. Interpretation of

environmental conditions during these phases are complicated by difficulties of

dating. In sediments from the northern areas, north of 28oS, the prominence of

tropical woodland polllen suggests that the period between 7000 and 6500 yr BP

was associated with optimal temperatures during the Holocene. Identifying the

warmest phase in the southern high-lying grasslands and semi-arid Karoo

shrublands south of 28oS is difficult, because unlike the savanna areas of the

north, they do not yield good pollen indicators for changes in termperature such

as those of frost sensitive trees. However, some pollen sequences from further

south along the southern coast of Africa (34oS) and at Marion Island in the

Southern Ocean (47oS), suggest that the Holocene temperature optimum occcurred

at about the same time in the sub-antarctic area in the south and the

subtropical regions in the north. The advent of moister conditions in southern

Africa during the early to middle Holocene, is generally recorded earlier (ca.

7500 - 6500 yr BP) in the north at ca. 26oS, than around 31oS, (ca. 5000 yr BP).

This change is provisionally associated with a relative shift in seasonality

from a predominance of all-season precipitation to a greater proportion of

summer rainfall, which apparently reached the southern Karoo areas two thousand

years later than the northern Bushveld region.

Ref ID : 1436

1789. Scott, L. Palynology of late pleistocene hyrax middens, South Western Cape

Province, South Africa: A prelimanary report. Historical Biology 9:71-81, 1994.

Reprint : In File,

Keywords : WESTERN CAPE; FYNBOS; PLANT-ANIMAL INTERACTIONS; VEGETATION CHANGE

Abstract : Botanical remains, especially pollen, preserved in dung middens of

rock-dwelling hyraxes (herbivorous mammals belonging to the genus Procavia) have

been studied in the Southern African winter-rainfall area. Seven middens from a

single rock shelter on the north-eastern side of the Cederberg mountain range,

Cape Province, are dated by 15 radiocarbon age determinations to between about

19,700 and 1370 yr BP. Plant remains in the middens are mainly fine, partly

digested fragments. Identifiable macro-botanical rests like seeds are scarce,

therefore this preliminary investigation is focused on analysis of abundant

pollen grains. The results show changes in a Southern Hemisphere equivalent of

the Mediterranean macchia vegetation, viz. "fynbos". Although "fynbos"

prevailed at the site throughout the studied period, an altitudinal lowering of

vegetation belts is indicated during the Last Glacial Maximum, while an increase

in arboreal pollen types, especially Dodonea, is shown during terminal

Pleistocene and Holocene times.

Ref ID : 90

1790. Scott, L. Past vegetation changes in mountainous areas in South Africa as

revealed by pollen analysis of hydrax middens. Proceedings of the XIII Plenary

Meeting of AETFAT. Seyani, J.H. and Chikuni, A.C.Anonymous Zomba, Malawi:2:1007-

1014, 1994. Ancient as well as recent hyrax middens which contain fossil pollen

records, have been found in mountainous areas in three different parts of SA.,

viz. the Orange Free State, the Karoo and the south-western Cape. Fluctuations

in pollen sequences can be interpreted as changes in past environmental

conditions during historical and prehistorial (Quarternary) times. The

indications are compared with results from independent observations of change

based on historical and palaeoenvironmental proxy data. The results show that

the influence of past climatic change and possibly more recent stock grazing

activities are reflected in the pollen records.

Reprint : In File,

Keywords : PALAEOENVIRONMENTS; VEGETATION CHANGE; FREE STATE

Ref ID : 791

1791. Scott, L. Pollen evidence for vegetation and climate change in Southern

Africa during the Neogene and Quaternary. In: Paleoclimate and evolution with

emphasis on human origins. edited by Vrba, E.S., Denton, G.H., Partridge, T.C.,

and Burckle, L.H.Yale:Yale University Press, 1995,p. 65-76.

Reprint : Not in File,

Keywords : PALAEOENVIRONMENTS; CLIMATE CHANGE; VEGETATION CHANGE; ENVIRONMENTAL

HISTORY

Ref ID : 1435



1792. Scott, L. Palynology of hyrax middens: 2000 years of palaeoenviromental

history of Namibia. Quaternary International 33:73-79, 1996.

Reprint : In File,

Keywords : NAMIBIA; SOUTHERN AFRICA; PLANT-ANIMAL INTERACTIONS; VEGETATION

CHANGE; GEOMORPHOLOGY; DESERTIFICATION ASSESSMENT

Abstract : Well-preserved and dateable faunal middens in rock shelters of dry

areas in southern Africa occur as desiccated urine-rich masses. Under local

conditions, which exclude microbial decomposition and oxidation, urine cements

together faecal pellets and other inclusions. Nine radiocarbon dated hyrax

(Procavia capensis) dung middens from the Kuiseb River Basin of the Namib Desert

were sub-sampled and analysed for fossil pollen. Some contain small proporations

of rat droppings, but not many macro-fossils. Comparative modern pollen in

faecal samples were also studied. Most plant macro-fossils are severely

digested, but seeds are well-preserved. Some insect inclusions were identified.

Small scale changes in vegetation over the last two millennia were observed,

representing environmental fluctuations in cycles of ca. 100 - 200 years. The

fluctuations partly agree with other palynological data from southern Africa and

with geomorphologic evidence for environmental changes in the desert region.

Ref ID : 1112

1793. Scott, L. Quaternary environment. In: Encyclopedia of Precolonial Africa,

edited by Vogel, J.O.London:Altamira Press, 1997,p. 42-45.

Reprint : Not in File,

Keywords : PALAEOENVIRONMENTS; VEGETATION CHANGE

Ref ID : 1113

1794. Scott, L. The vegetation history and climate in the Savanna Biome, South

Africa, since 190 000 KA: A comparison of pollen data from the Tswaing Crater

(the Pretoria Saltpan) and Wonderkrater. Quaternary International 1998.(In

Press)


Reprint : Not in File,

Keywords : SAVANNA; VEGETATION CHANGE; ENVIRONMENTAL HISTORY; PALAEOENVIRONMENTS

Ref ID : 1111

1795. Scott, L., Anderson, J.M., and Anderson, H. Vegetation history. In: The

vegetation of Southern Africa, edited by Cowling, R.M. and Richardson,

D.Cambridge:Cambridge University Press, 1997,p. 62-84.

Reprint : Not in File,

Keywords : PALAEOENVIRONMENTS; VEGETATION CHANGE; ENVIRONMENTAL HISTORY

Ref ID : 1011

1796. Scott, L. and Bousman, C.B. Palynological analysis of hyrax middens from

southern Africa. Palaeogeography, Palaeoclimatology, Palaeoecology 76:367-379,

1990.


Reprint : In File,

Keywords : PALAEOENVIRONMENTS; MICROMAMMALS; ENVIRONMENTAL HISTORY

Ref ID : 1438

1797. Scott, L. and Bousman, C.B. Palynological analysis of hyrax middens from

Southern Africa. Paleogeography, Paleoclimatology, Paleoecology. 76:367-379,

1990.


Reprint : In File,

Keywords : PLANT-ANIMAL INTERACTIONS; KAROO DESERTIFICATION; CLIMATE; CLIMATE

CHANGE; GRASSLAND; RAINFALL; VEGETATION CHANGE; GRAZING EFFECTS

Abstract : Hyrax middens in relatively dry parts of Africa preserve plant

material which includes pollen. The bottoms of two stratified hyrax dung

middens from Blydefontein Basin in the Karoo shrubland of SA, were dated by

radiocarbon to ca. 300 yr BP. and ca. 1 130 yr. BP. Comparison of midden pollen

spectra with pollen from alluvial sediments near one of the hyrax middens, and

in modern surface samples, indicates that middens contain pollen which reflects

local vegetation, and that diet probably does not have a major influence on

pollen spectra. Changes in pollen composition probably reflect climatic

conditions during the early history of the older midden profile. Grass

dominated spectra suggest moist conditions existed between 1 200 and 300 yr.

BP., and an interval of slightly more shrubby karoid vegetation possibly points

to a minor dry spell at 1 000 yr. BP. A sharp increase of karoid shrub

vegetation, and a decrease of grass since 300 yr. BP. is reflected in both

middens. The change was apparently triggered by relatively dry conditions, and

later, during the last 150 years, it was enhanced by overgrazing from European

domestic stock.

Ref ID : 1434

1798. Scott, L. and Brink, J.S. Quaternary palaeoenviroments of pans in Central

South Africa: palynological and palaeontological evidence. SA Geograaf

19(1/2):22-34, 1992.

Reprint : In File,

Keywords : FREE STATE; PALAEOENVIRONMENTS; SOIL NUTRIENTS; PLANT-ANIMAL

INTERACTIONS; WATER QUALITY

Abstract : Various palaeontological remains have been found in springs, sandy

lunettes and floor deposits at pans in SA. While peaty deposits are useful for

pollen analysis, sands or clays provide better conditions for the preservation

of bones and polleniferous coprolites. Fossil pollen and vertebrate remains

from two pans (at Florisbad and Deelpan) in the Orange Free State are reviewed

in order to make possible a more coherent Quarternary palaeoenvironmental

reconstruction than was available previously. Substantially higher palaeo-lake

levels are suggested by the faunal and pollen remains in some strata. Mud

cracks in pan floors which form during dry periods are identified as possible

sources of younger pollen contamination in ancient lake desposits.

Ref ID : 1550

1799. Scott, L. and Steenkamp, M. Environmental history and recent human

influence at coastal Lake Teza, KwaZulu-Natal. South African Journal of Science

92:348-350, 1996.

Reprint : In File,

Keywords : ENVIRONMENTAL HISTORY; KWAZULU NATAL; HYDROLOGY; SEDIMENTATION; LAND

DEGRADATION; PLANT-ANIMAL INTERACTIONS; VEGETATION CHANGE

Abstract : Preliminary results of pollen analysis and dating of a sediment core

from coastal Lake Teza, KwaZulu-Natal, suggest that sea levels in the area were

high during the Holocene until shortly before ca. 3 400 yr BP. Environmental

changes which resulted from recent human impact left a record in lake deposits.

Sedimentation rates in the lake basin have increased greatly during recent

decades, suggesting that human activities have had a marked effect on the lake.

The implication of this investigation is that the quality of this and other

coastal lakes in central to northern KwaZulu-Natal will continue to deteriorate

at an increased rate as the lakes get progressively shallower.

Ref ID : 214

1800. Scott, L. and Vogel, J.C. Short-term changes of climate and vegetation

revealed by pollen analysis of hyrax dung in South Africa. Review of

Palaeobotany and Palynology 74:283-291, 1992.

Reprint : In File,

Keywords : PALAEOENVIRONMENTS; CLIMATE; VEGETATION CHANGE; STOCKING RATE

Abstract : A pollen sequence in a relatively young hyrax dung midden in the

Orange Free State, South Africa, shows marked changes in composition which can

be related to environmental fluctuations. The midden from Clarens was dated by

radiocarbon to the last thirty years on the basis of recent radiocarbon

concentration levels of the atmosphere, which were artificially increased by

extensive nuclear arms testing after 1954. Fluctuations in the pollen contents

of the dung sequence conform with recent vegetation changes between 1947 and

1990, which are revealed by a series of air- and other photographs. Details of

the fluctuating pollen sequence can further be interpreted in terms of short-

term meteorological changes which have been recorded at a nearby weather station

in Bethlehem, Orange Free State, and in terms of the effects of stock grazing on

vegetation of the area.

Ref ID : 2433

1801. Segar, J. Health care at village level: Transkei and Ciskei. Journal of

Contemporary African Studies 2(2), 1992.

Reprint : Not in File,

Keywords : TRANSKEI; CISKEI; POPULATION; SOCIOECONOMIC ASPECTS

Notes : The purpose of the study was to focus on the differentiation in the

distribution of diseases and in health care services within and between the

Transkei and Ciskei, concentrating specifically on how these differences are

experienced at the village level. Information for the study was gathered from

secondary sources: from the Departments of Health, Social Welfare and Population

Development. At the macro level, health care provision in the Ciskei was

superior to that of the Transkei, resulting in an improvement in health amongst

Ciskeians. The Ciskei had a lower infant mortality rate than the Transkei.

Information on health care at the village level at Matatiele in the Transkei and

Keiskammahoek in the Ciskei is contained in the report. This article is

obtainable from the Border Rural Committee, East London. See also ref. I.D. no

2339.

Ref ID : 1465



1802. Semmelink, M. Land degradation in the lowlands of Lesotho and factors

which contribute to land degradation with examples from Qeme East catchment

area.UCT - Department of Environmental and Geographic Science, Lesotho 1985. ,

1985.


Reprint : Not in File,

Keywords : LAND DEGRADATION; LESOTHO; DESERTIFICATION ASSESSMENT

Notes : UCT ENGEO Accession No. 8500663.

Ref ID : 605

1803. Seneque, G.C. Betterment planning in South Africa.University of Natal,

Pietermaritzburg. , 1982. Master of Science.

Reprint : In File,

Keywords : AGRICULTURAL DEVELOPMENT; COMMUNAL AREA; BETTERMENT PLANNING; MAPS

Notes : The author concludes that planners on the subjective level, are so often

obsessed with "tidying up the landscape", in creating neat grid layouts and re-

ordering the environment to fit the various colours they have daubed on a map in

the splendid isolation of their offices. For them the quintessance of

creativity and design must be a Mondrain painting. The ability of planners to

recognise the multi-dimensionality of other social groups' perceptions of their

environment, is severely limited. The history of the conception and

implementation of Betterment Planning in SA bears testimony to this. Planners

who ignore this history, who do not understand it, who are not able to plan

without the power of the gun, will fail.

Ref ID : 1960

1804. Seuffert, O., Herrig, K., Ollesch, G., and Busche, D. An integrated

erosivity index for assessing and correlating rainfall structure, runoff and

erosion. Geo-oko-dynamik XX(1/2):1-52, 1999.

Reprint : Not in File,

Keywords : RAINFALL; RUNOFF; EROSION

Ref ID : 2276

1805. Seymour, C. Different grazing intensities in arid rangelands: effects on

invertebrates on a communal farm in the Succulent Karoo, South Africa.University

of Cape Town. , 1998.

Reprint : Not in File,

Keywords : SUCCULENT KAROO

Notes : MSc thesis.

Ref ID : 1466

1806. Seymour, J. Soil erosion: can we dam the flood? Ecos 25:3, 1980.

Reprint : Not in File,

Keywords : SOIL EROSION; EROSION; FLOODS; DESERTIFICATION CONTROL; IRRIGATION

Ref ID : 1402

1807. Shackelton, C.M. Fuelwood harvesting and sustainable utilisation in a

communal grazing land and protected area of the eastern Transvaal lowveld.

Biological Conservation 63:247-254, 1993.

Reprint : In File,

Keywords : COMMUNAL AREA; DEFORESTATION; MPUMALANGA; SAVANNA; BIODIVERSITY

Abstract : The species composition and woody standing crop was determined for

two adjacent sites of contrasting management history in the eastern Transvaal

Lowveld - a communal land that has been subject to wood harvesting for several

decades and an adjacent unharvested site. Results indicated a significant loss

of species richness in the harvested site. Total woody standing crop was little

altered despite the long history of harvesting pressure. However, the amount of

dead wood was significantly reduced in the harvested site. No adverse effects

of such biomass removal were detected. Harvesters actively selected or avoided

particular species and size classes.

Ref ID : 404

1808. Shackelton, C.M. Demography and dynamics of the dominant woody species in

a communal and protected area of the eastern Transvaal Lowveld. South African

Journal of Botany 59:569-574, 1993.

Reprint : In File,

Keywords : COMMUNAL AREA; GRAZING EFFECTS; BUSH ENCROACHMENT; MPUMALANGA;

SAVANNA; POPULATION

Abstract : The size class distributions of the seven most abundant woody species

in an area of the Transvaal Lowveld were determined for two contrasting

management systems, i.e. communal land and a protected area. Most of the size

class profiles indicated that the populations were not stable, experiencing

fluctuating recruitment and/or mortality rates. This is probably the norm in

semi-arid environments characterized by large fluctuations in the timing and

intensity of controlling variables. Communal management reduced absolute

densities and altered the size class profile of all but one of the species

considered. This was usually manifested as a reduction in the proportion of

larger individuals.

Ref ID : 1786

1809. Shackelton, C.M. Are the communal grazing lands in need of saving?

Development Southern Africa 10(1):65-79, 1993.

Reprint : In File,

Keywords : GRASSLAND; SOUTHERN AFRICA

Abstract : The condition, productivity and profitability of the communal

grasslands in the southern African 'homelands' are assessed by review of the

published data. There is very little empirical data from the communal

grasslands themselves. These data, supported by other circumstantial evidence,

do not support the often-held notion that the communal grasslands are severely

degraded and beyond recovery. This is especially so for the moist and mesic

areas of southern Africa. Results from the arid areas are variable.

Ref ID : 2340

1810. Shackelton, C.M. Annual production of harvestable deadwood in semi-arid

savannas, South Africa. Forest Ecology and Management 112:139-144, 1998.

Reprint : In File,

Keywords : SAVANNA; RAINFALL; PRODUCTION POTENTIAL; BIODIVERSITY; SUSTAINABLE

DEVELOPMENT; AGRICULTURAL PRODUCTION

Abstract : The annual production of deadwood available for harvesting by hand

was determined from 28 permanent plots over three years for three protected

areas along a rainfall gradient. Annual production varied considerably for

individual plots, but the mean production per woody standing biomass was

relatively constant from year to year at approximately 17 kg/ha/year per ton

live biomass, or 1.7% per annum. Annual production of harvestable deadwood was

related more to stand biomass than rainfall zone. The relative consistency of

production rates has positive implications for sustainable use and harvesting

strategies.

Ref ID : 1294

1811. Shackelton, S.E., Stadler, J.J., Jeenes, K.A., Pollard, S.R., and Gear,

J.S. Adaptive strategies of the poor in arid and semi-arid lands: in search of

sustainabe livelihoods - a case study of the Bushbuckridge district, eastern

Transvaal, South Africa.Anonymous Wits Rural Facility:University of the

Witwatersrand. , 1995. This study on adaptive strategies and sustainable

livelihoods was commissioned by the International Institute for Sustainable

Development (IISD), Canada as part of the five-nation African initiative. The

study was undertaken in the semi-arid savanna region of the Bushbuckridge

district, Eastern Transvaal, South Africa by a multidisciplinary team of

researchers from Wits Rural Facility (WRF). The research drew on both secondary

sources of data for the study area and on a case study conducted in the village

of Tshunelani. A qualitative approach was used for the fieldwork, relying

mainly on participatory rural appraisal (PRA) techniques and key informant

interviews. The advantages and disadvantages of this approach are discussed in

detail in the methods section. A major challenge for the team in our attempts

to interpret the findings related to the concepts of "adaptive strategy" and


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