Bibliography: Land Degradation in South Africa project

systems and the physiognomy, demography and phenology of karoo plants. Secondly,

it characterizes the floristics, structure and dynamics of three subropical

thicket communities and a karroid shrubland community along an environmental

gradient in the lower Sundays River Valley, south eastern Cape. Both objectives

fall within the overall aims of the Karoo Biome Project of which this study is

part. From the two reviews, I conclude that most research in the semi-arid

Karoo has stalled in the descriptive phase and there has been little emphasis on

the demographic responses of plants to the stochastic events which characterize

this region. In addition, current views of the dynamics of karoo communities

are steeped in paradigms which consider the Karoo to be composed of relatively

stable populations. I present evidence that this may not be the case and

suggest that such views are thus probably unable to provide the necessary

insights to manage this resource effectively. Similarly, the rationale for

existing management systems consists mostly of untested or untestable statements

and there is a lack of critical investigation in the published literature. In

the gradient analysis study I show that the lower Sundays River Valley is

characterized by a complex gradient of increasing aridity. Rainfall

predictability, the occurrence of relatively severe night frosts and low plant

available water status of the Karoo are probably the chief factors which delimit

the boundary between this dwarf shrubland and the subtropical thicket

communities in the eastern Cape. I show that under sustained grazing pressure,

karroid species typical of the Central Lower Karoo, invade subtropical thicket

communities but this appears confined to the Noorsveld, a veld type adjacent to

it. There is not a wide-spread invasion of karroid elements into the Sundays

River Scrub and Addo Bush. Diversity within the lower Sundays River Valley

vegetation is not correlated with phytochorological or structural diversity and

there is no increase in the middle part of the gradient as has been reported in

a number of other studies. I confirm most of the earlier views concerning the

phytochorology of the eastern Cape flora. However, I present evidence to show

that the subtropical thickets may have been present in the eastern Cape for much

longer than previously suggested. An analysis of the phenology of the

subtropical thicket and karroid shrubland vegetation shows that the Karoo may

follow a "pulse-activity" response to a relatively unpredictable moisture

supply. This differs from current views of karoo dynamics which emphasize the

seasonal specialization of growth forms. Finally, I discuss the main findings

of this study in the light of the hypotheses tested and generated and I suggest

possible future research directions.

Reprint : In File,

Keywords : EASTERN CAPE; POPULATION; RAINFALL; GRAZING EFFECTS; PLANT

PHYSIOLOGY; SUCCULENT KAROO; VEGETATION DYNAMICS; VELD MANAGEMENT; BUSH

ENCROACHMENT; BIODIVERSITY; CLIMATE CHANGE

Ref ID : 44

1109. Hoffman, M.T. Is the Karoo spreading? Veld & Flora 77(1):4-7, 1991.

Reprint : In File,

Keywords : KAROO DESERTIFICATION; ENVIRONMENTAL HISTORY; NAMA KAROO; GRASSLAND;

DESERTIFICATION ASSESSMENT; VEGETATION CHANGE; RAINFALL

Notes : The author concludes that matched photographs and survey data indicate

that there is no evidence to suggest that the Karoo is steadily expanding its

range into the southern OFS grasslands, at least not at a predictable annual

rate. On the contrary, the opposite was found to be the case. (It is not

suggested, however, that the grasslands are "invading" the Karoo). There are,

however, alternative explanations. The semi-arid eastern Karoo is characterised

by large fluctuations in grass cover, determined mostly by the amount of summer

rainfall. On the other hand it is suggested that there is no change in the

Karoo and southern OFS vegetation apart from cyclical fluctuations which occur

over decades. Unfortunately, the validity of any one of a number of theories of

vegetation change in the eastern Karoo will only be decided by long-term

research, if at all. Such a venture, however, is costly and would yield few

immediate rewards. Perhaps because of this we may not receive a definitie

answer for some time to come.

Ref ID : 1069

1110. Hoffman, M.T. The potential value of historical ecology to environmental

monitoring. Paper presented at a conference on "Monitoring requirements for

fynbos management", 16-17 March 1993, Swellendam. 1993.

Reprint : In File,

Keywords : ENVIRONMENTAL HISTORY; MONITORING; GLOBAL CHANGE; ARCHAEOLOGY;

SOUTHERN AFRICA; STOCKING RATE; BOTANICAL SURVEY

Abstract : The current world-wide focus on global change has led to a co-

incident upsurge in the study of environmental history. This link between the

two is important since it allows researchers to better assess the rate and

extent of current and future changes in the light of past changes. Historical

environmental monitoring demands a synthetic approach to understanding landscape

change. It uses information from a wide range of diciplines including

palynology, archaeology, anthropology, geography, geology, history, ecology and

many more. The focus of this paper is to review the main historical sources and

tools that have and could be used to understand vegetation and landscape change

in southern Africa during the last two hundred years and in particular during

the last hundred years. Some examples of studies, which have used a variety of

hisorical documents such as land grant documents, Field Cornet's reports,

traveller's records, stocking rate records and newspaper reports, are listed.

The value and limitations to the information retrieved from such material is

discussed. Similarly, the value and use of botanical survey data is noted. A

main emphasis of this review is to highlight the value of using a Markov

modelling approach in the study of ground and aerial photograph interpretation

of landscape change. Finally, it is suggested that a study of landscape change

in southern Africa would benefit from as broad-based an historical approach as

possible and would include a wide variety of disciplines, sources and

techniques. However, the establishment of clear theoretical expectations,

hypotheses and questions based on a literature search of the problem, prior to

investigation, is crucial if success in historical enviornmental monitoring is

to be achieved.

Ref ID : 238

1111. Hoffman, M.T. Environmental history and the desertification of the Karoo,

South Africa. Giornale Botanico Italiano 129(1):261-273, 1995.

Reprint : In File,

Keywords : ENVIRONMENTAL HISTORY; VEGETATION CHANGE; DESERTIFICATION ASSESSMENT;

KAROO DESERTIFICATION; NAMA KAROO; GRASSLAND

Abstract : This paper reviews the desertification debate in South Africa and

emphasizes the methods that have been used to understand the environmental

history of the semi-arid rangelands in the eastern Karoo during the last 500

years. These mixed grass/dwarf shrub rangelands, with mean annual rainfall

totals typically between 300-400mm, are described and the main driving variables

discussed. A brief historical account of the European settlement of the region

is also presented. The desertification debate has focussed on three main issues.

Firstly, because arid and semi-arid lands appear to be heavily influenced by

climate, the changing climatic regime during the Holocene and particularly

during the last two hundred years has been the subject of intensive

investigation. While all studies conclude that there is no evidence in the

historical record to support the popular perception that rainfall totals have

decreased this century, the question of changing rainfall seasonality has not

been adequately explored. Although mean annual temperatures over the last 50

years have not changed there have been significant increases in mean monthly

maximum temperatures and significant decreases in mean monthly minimum

temperatures for some of the stations investigated. The second issue of great

interest in the South African desertification literature is that of the nature

of pre-conlonial environments. A wide variety of archaeological, historical and

ecological techniques have been used, including analyses of fossil mammal bones

in owl pellets, fossil pollen in hyrax middens, notes from fossil mammal bones.

While all authors agree that the eastern Karoo was more grassy at some stage in

the past there is disagreement as to both the timing and cause of the changes to

a more shrubby vegetation. The final issue of great concern to the

desertification debate in South Africa concerns the rate of change during the

last 100 years. Satellite imagery, matched ground and aerial photography, survey

data and an analysis of historical stock records cannot agree as to whether the

Karoo is degrading or not. Certainly, the classic view of an annually expanding

desert margin has been replaced in recent years by a more realistic

understanding of the seasonal dynamics of the vegetation. The recent trend to

detailed modelling of the demographic process in key species holds much promise

for our undestanding of the degradation process. The vibrant community of

researchers, employing a range of archaeological, historical and ecological

techniques, will make important contributions to South Africa's National Action

Plan to Combat Desertification.

Ref ID : 249

1112. Hoffman, M.T. Human impacts on vegetation. In: Vegetation of Southern

Africa. edited by Cowling, R.M., Richardson, D.M., and Pierce,

S.M.Cambridge:Cambridge University Press, 1997,p. 507-534.

Reprint : In File,

Keywords : ENVIRONMENTAL HISTORY; VEGETATION CHANGE; DESERTIFICATION ASSESSMENT;

LAND DEGRADATION; STOCKING RATE; KAROO DESERTIFICATION; CONSERVATION; BUSH

ENCROACHMENT; GRAZING EFFECTS; SOUTHERN AFRICA; MODELS; POPULATION; FOREST;

LEGISLATION; POLICY

Notes : The author concludes by saying that the 'classical' view of land

degradation in southern Africa, which holds that the most devastating influences

on the vegetation of the region have occurred in the past several decades, is

rejected as being too general. The extent and severity of human impacts cannot

be viewed simply as an exponential increase with time. Each region has its

unique history and even within-biome generalizations are problematic. Certainly

many areas in southern Africa fit this general model and remain under threat

from increasingly excessive exploitation. Also, the demands made on the land by

a burgeoning population are cause for deep concern within both governmental and

environmental agencies. However, there are cases (e.g. the Knysna forest, the

eastern Karoo, the Limpopo Basin and eastern Kalahari) where severe and

nonsustainable exploitation of the resource base occurred earlier this century

or even earlier this millennium. In many instances, current legislation,

coupled with an increasing environmental awareness amongst land users and

managers, has changed exploitation practices to those that are more sustainable

in the long term. It seems that one of the best ways to prepare for the future

is to understand the trends and patterns of the past. Although extrapolation of

these historical trends into the future is problematic, southern African policy

makers and indeed the community at large should take note of the political and

cultural devastation created by past environmental degradation such as has been

postulated for the Limpopo Basin state in and around Mapungubwe more than 600

years ago (Hall 1987). Perhaps more than anything else we need to understand

the long-term implications of the region's rapid population growth rate on our

environment, since the health of our primary resource base affects people's

livelihoods directly. Indeed, the future of all southern Africa's people rests

ultimately on its renewable, natural resources.

Ref ID : 228

1113. Hoffman, M.T., Barr, G.D., and Cowling, R.M. Vegetation dynamics in the

semi-arid eastern Karoo, South Africa: the effect of seasonal rainfall and

competition on grass and shrub basal cover. South African Journal of Science

86:462-463, 1990.

Reprint : In File,

Keywords : KAROO DESERTIFICATION; VEGETATION CHANGE; VEGETATION DYNAMICS

Abstract : Using regression analyses, we examined three hypotheses concerning

grass and shrub basal cover fluctuations in the eastern Karoo. We accepted the

hypothesis that an increase in summer rain would result in increased grass

cover. We rejected the hypothesis that an increase in winter rain would result

in an increase in shrub basal cover. We suggested instead that shrub cover

decrease may be influenced by grass cover increase and that these two growth

forms may compete for resources. We speculate on the implications of our

analysis for vegetation dynamics in the eastern Karoo.

Ref ID : 234

1114. Hoffman, M.T., Bond, W.J., and Stock, W.D. Desertification of the eastern

Karoo, South Africa - conflicting palaeoecological, historical, and soil

isotopic evidence. Environmental Monitoring & Assessment 37(1-3):159-177, 1995.

Reprint : In File,

Keywords : PALAEOENVIRONMENTS; ARCHAEOLOGY; KAROO DESERTIFICATION;

DESERTIFICATION ASSESSMENT; MONITORING; STOCKING RATE; VEGETATION DYNAMICS

Abstract : TP549-0012 The desertification debate in South Africa has benefitted

greatly in recent years from the contributions of a wide range of disciplines.

In this paper we review the conflicting and supporting evidence for degradation

in the eastern Karoo as reported in recent archaeological, historical, and

stable carbon isotope studies as it relates to three key aspects of the debate:

the precolonial environment, the rate and nature of change, and the relative

contributions of humans and climate to the process. First, all studies suggest a

greater grassiness at some time in the past, but researchers disagree on the

timing of the switch to more shrubby conditions in the eastern Karoo. Second,

regional rainfall records for the past 2 decades reveal an above-average

rainfall period, and numerous long-term surveys show an increase in grass cover

over the same period. These findings question the expanding Karoo hypothesis as

well as the argument that the Karoo's carrying capacity has decreased in recent

years. Finally, the relative responsibilities of humans and climate in the

degradation process remain poorly understood and generally have not formed the

focus of investigation. [References: 36] Reprint available from: Hoffman MT NATL

BOT INST PRIVATE BAG X7 CLAREMONT 7735 SOUTH AFRICA.

Ref ID : 49

1115. Hoffman, M.T., Cousins, B., Meyer, T.C., Petersen, A., and Hendricks, H.

Historical and contemporary agricultural land use and the desertification of the

Karoo. In: The Karoo: ecological patterns and processes. edited by Dean, W.R.J.

and Milton, S.J.Cambridge University Press, 1999,

Reprint : Not in File,

Keywords : LAND USE; COMMUNAL AREA; PRODUCTION POTENTIAL; KAROO DESERTIFICATION;

ENVIRONMENTAL HISTORY; GRAZING EFFECTS; DESERTIFICATION ASSESSMENT

Ref ID : 155

1116. Hoffman, M.T. and Cowling, R.M. Vegetation change in the semi-arid eastern

Karoo over the last 200 years: an expanding Karoo - fact or fiction? South

African Journal of Science 86:286-294, 1990.

Reprint : In File,

Keywords : VEGETATION CHANGE; ENVIRONMENTAL HISTORY; KAROO DESERTIFICATION;

GRAZING EFFECTS; VEGETATION DYNAMICS

Abstract : We present historical and photographic evidence and survey data to

test current theory of vegetation change in the eastern Karoo and southern

Orange Free State (OFS) over the last two hundred years. This theory states that

the eastern Karoo has been altered from a perennial grassland to a dwarf

shrubland which is invading the southern OFS grasslands at a predictable rate.

We find little support for this and propose an alternative view of vegetation

change in the region. We suggest that the pre-colonial eastern Karoo may not

have been dominated by perennial grasses and that seasonal rainfall effects

might be responsible for much of the perceived vegetation change in the eastern

Karoo and southern OFS.

Ref ID : 48

1117. Hoffman, M.T. and Cowling, R.M. Desertification in the lower Sundays River

Valley, South Africa. Journal of Arid Environments 19:105-117, 1990.

Reprint : In File,

Keywords : DESERTIFICATION ASSESSMENT; LAND USE; KAROO DESERTIFICATION;

VEGETATION DYNAMICS; GRAZING EFFECTS

Abstract : Extensive desertification, over the next 100 years, has been

predicted for the eastern parts of South Africa. Using multivariate

classification and ordination techniques for data from the lower Sundays River

Valley, eastern Cape, we provide supporting evidence for a limited expansion of

karroid shrublands into adjacent succulent sub-tropical thicket. Karroid

shrublands appear more resilient to sustained grazing pressure than do mesic

sub-tropical thicket vegetation types.

Ref ID : 1345

1118. Hoffman, M.T., Milton, S.J., Roux, P.W., and Palmer, A.R. Report to the

intergovermental panel on climate change (IPCC). On climate change and

Desertification in South Africa. 1994.

Reprint : In File,

Keywords : CLIMATE; CLIMATE CHANGE; SOUTHERN AFRICA; AGRICULTURAL PRODUCTION;

DROUGHT; MONITORING; SUSTAINABLE DEVELOPMENT; SUBSIDIES; AID; LEGISLATION;

POPULATION

Notes : The authors conclude that: (1) The establishment of the details of the

desertification process in southern Africa is essential. The question remains

in the minds of some: "Has the region become desertified"? The formulation of a

national strategy to address the question is crucial. (2) There exists an

important need to establish the role of range management and the role of range

management research in combating the problem of desertification. (3) Continued

evaluation of long-term climatic records to prepare realistic expectations for

agriculture in the region and to evaluate trends in climate. (4) Having

established realistic expectations for agricultural production, land

redistribution should be carried out within the constraints of these findings.

(5) The development of a comprehensive drought management strategy for SA that

benefits all users of the land. (6) Expansion of bench-mark sites (vegetation

monitoring sites) to more areas in the arid and semi-arid zones of southern

Africa so as to develop accurate assessments of changes in vegetation and

rangeland states. (7) Development of research programmes focused on the question

of sustainable development. (8) Investigation into the potential negative role

that subsidies and other financial aid packages may play in "keeping the farmer

on the land" at all costs. (9) Establish regional research and agricultural

ties so as to improve regional co-operation. (10) Development of adequate

legislation, incentives and law enforcement that deal specifically with

desertification. (11) Determine the role of regional and national population

pressure on the rate, severity and extent of desertification in southern Africa.

(12) Inclusion of South Africans in international desertification debates and

conventions is crucial if we are to learn from and contribute to regional plans

of action.

Ref ID : 2503

1119. Holbrook, G. Lessons to be learned from two irrigation schemes.

Development Southern Africa , 1996.

Reprint : Not in File,

Keywords : IRRIGATION; CISKEI; AGRICULTURAL DEVELOPMENT; ECONOMIC ASPECTS;

POLITICAL ASPECTS

Notes : The purpose of the study was to investigate the two irrigation schemes,

make a comparison in terms of development and context of each scheme, and draw

lessons to be learned for future use in similar schemes. The author did

fieldwork, which was conducted in 1987 and 1990 at the Tyefu Irrigation Scheme,

and in 1992 at the Keiskammahoek Irrigation Scheme. Although the Tyefu and

Keiskammahoek Irrigation Schemes (2 small, initially centralised schemes) were

implemented in the same year, they are quite different from each other. A

comparison of the development and the context of each scheme provided insight

into small capital-intensive irrigation projects. Lessons that can be learned

include the effects of politics and agricultural management on production, the

role of the environment in managing such schemes, and the importance of

considering changes in the relationship between management and local

participants. This article can be obtained from the Document Centre, Faculty of

Agriculture, University of Fort Hare. See also ID ref. no. 2339.

Ref ID : 2570

1120. Holbrook, G. The politics of livestock management: the case study of the

village of Guquka. Proceedings of a symposium on policy-making for the

sustainable use of Southern African communal rangelands.Anonymous Anonymous ,

1998.

Reprint : Not in File,

Keywords : CISKEI; POLICY; SOCIOECONOMIC ASPECTS; LIVESTOCK PRODUCTION;

POLITICAL ASPECTS

Notes : The purpose of the study was to explore the relationship between old

established households and moral authority, by looking at the way livestock

products are shared in the village. The method used was case study. In Guquka

the principles of race, ethnicity and centralisation that shaped politics in the

past have been de-emphasised. What has been stressed is age and

decentralisation. Though the way livestock and sharing are controlled in the

village, multiple homestead households and their leaders continue to influence

former village politics despite the apparent fluidity of contemporary political

organisation. This paper is available at the Document Centre, Agriculture,

University of Fort Hare. See also ID ref. no. 2339.

Ref ID : 2539

1121. Holbrook, G. Shoring up hydraulic despotism: class race and ethnicity in

irrigation politics in the Eastern Cape Province, South Africa. Journal of

Contemporary African Studies , 1998.

Reprint : Not in File,

Keywords : IRRIGATION; EASTERN CAPE; TRANSKEI; CISKEI; POLITICAL ASPECTS;