bluuebunny/crossref_metadata_2025 huggingface dataset:
Age, Descent and Elders among the Pokomo
Authors: Townsend Norman
Published: April 2006

Introduction

A number of writers have noted that for East Africa, age organization and lineage organization are structural alternatives. More precisely, Southall (1970) has argued that the full and dominant development of age organization is incompatible with that of a segmentary lineage structure. Forde (1971) has similarly concluded that the two may be alternatives, and that selection between them may be partly dependent on ecological factors. However, I would like to contend that to write of the elaboration, or non-elaboration, of age structures and descent groups or of a conflict of allegiances, may well be a sterile exercise if it is unrelated to an analysis of the mode of livelihood of the people concerned. Furthermore, in light of the modern view of social structure as the outcome, at any point in time, of continuous processes of destructuring and restructuring, the ceaseless turnover of the membership of society, which age structures attempt to reduce to order, can be seen as one of the major sources of these processes, as Bottomore has recently argued (1975). Thus a source of structural stress, and hence ultimately of change, more important, I would argue, than the conflict between age and descent, is that between the generations.
Gerontocratic Government: Age-Sets in Pre-Colonial Giriama
Authors: Brantley Cynthia
Published: April 2006

Opening Paragraph

In the protection of their kaya home deep in the forest of the Mombasa hinterland, the Giriama of Kenya developed a non-centralized government based on a council of elders (kambi), and derived from age-sets. They were supported by a special secret society within the kambi whose oath and select membership were used to maintain order and determine guilt in difficult situations. In the period from approximately 1700 until sometime in the nineteenth century, the Giriama developed this form of government by drawing upon their previous experience of life in Singwaya and subsequent southward migration, upon their identification or assimilation of members into six original clans, and upon their unique environment of the kaya neighborhood to become successful cultivators, keeping cattle when circumstances allowed and emerging as the prominent traders of the Mombasa hinterland.
Woman-Marriage, with Special Reference to the Louedu—its Significance for the Definition of Marriage
Authors: Krige Eileen Jensen
Published: April 2006

Opening Paragraph

The marriage of a woman to a woman, found in many African societies, has not been given the attention it warrants, and is still imperfectly understood. Herskovits imputed to it sexual overtones that are foreign to the institution when, after stating quite definitely that such marriage did not imply a homosexual relationship, he went on to add ‘although it is not to be doubted that occasionally homosexual women who have inherited wealth…utilize this relationship to the women they marry to satisfy themselves’ (Herskovits, 1938, 1: 319–20). He made no attempt to substantiate his statement. And Lucy Mair, for all the clarity and grasp displayed in her excellent book on marriage, seems to have failed to appreciate the nature of the institution when she says, ‘According to Evans-Pritchard's account of the Nuer it is usually barren women who make such marriages, and indeed it is hard to imagine a woman who had her own children doing so’ (my italics; Mair, 1971: 60). In actual fact it is usually married women with children of their own who contract such marriages, except, it would appear, among the Nuer. By woman-marriage we mean the institution by which it is possible for a woman to give bridewealth for, and marry, a woman, over whom and whose offspring she has full control, delegating to a male genitor the duties of procreation.
Kinship and Marriage in a Polyethnic Community
Authors: Arens W. , Arens Diana Antos
Published: April 2006

Introduction

Although Redfield's (1947) folk–urban continuum has been subjected to valid theoretical critiques (Miner 1952 and Mintz 1953) the tempting simplistic dichotomy this construct implies is still basic to our view of the social universe. Apparently anthropologists, like many of the groups they study, often prefer to conceptualize in dyadic terms. Thus, in an almost complete disregard for historical processes this proclivity has manifested itself in African studies by a contrast between a static ‘tribal’ hinterland opposed to a more dynamic urban domain. More recently as a mediating agent the tribal notion wound its way into African cities via a theoretical migration and re-emerged somewhat inelegantly as ‘supertribalism’ (Rouch 1956: 60), ‘urban tribalism’ (Gluckman 1960: 55) and ‘retribalization’ (Cohen 1969: 1–6). As a consequence the ‘tribe’ remains a basic conceptual category assumed applicable to both urban and rural Africa.
Marriage, descent and kinship: on the differential primacy of institutions in Luapula (Zambia) and Longana (New Hebrides)
Authors: Poewe Karla O. , Lovell Peter R.
Published: April 2006

Introduction

In this paper we examine the differential implications of kinship practices and, specifically, Crow kinship terminology for two societies, one African, the other Oceanic. The comparison is undertaken for the following reason. Keesing (1970:765) suggested that the gulf between the way he conceptualized the Kwaio system and the way Fortes (1969) and Goody (1973) conceptualized the African systems may well be far wider ‘than the gulf between what the Kwaio and Africans do. And if the gulf is generated more by the models than by the facts, we had better look very carefully at the models.’ The question arises, therefore, whether classic African descent models are different from Oceanic kinship models because the anthropologists are following different intellectual traditions, or whether these two sets of models are different because they reflect a very real difference in the institutional make-up of African and Oceanic societies?
The Nature and Effects of Differential Access to Education in Ga Society
Authors: Robertson Claire C.
Published: April 2006

Opening Paragraph

What happens when women are denied access, over a long period of time, to formal education of the type men are given? This paper is a preliminary examination of the effects on Central Accra Ga society of this process, which began in a significant form in the nineteenth century. It posits a detrimental effect, not only on the women but also on the whole society, and on the relation between the sexes, of the systematic channelling of men into Western style education, while women were encouraged to stay in trading and home production, or given the equivalent of ‘home economics’ courses if they were sent to school.
To catch a feastgiver: Redistribution among the Dorze of Ethiopia
Authors: Halperin Rhoda , Olmstead Judith
Published: April 2006

Opening Paragraph

The purpose of this paper is to examine in detail a mode of economic integration, redistribution, and its relationship to political power. The redistributive institution studied here involves assumption of the title halak'a by a male citizen. ‘We catch the halak'a!' say the Dorze (halak'a aikos), implying by their choice of verb that candidates show some reluctance to disburse their economic resources upon feasts and fees. During the ceremonies which create a titled incumbent from an initiate, large amounts of goods, services, and money are collected by the halak'a and used in lavish feasting. Pooling of resources and their subsequent reallocation mark as redistributive this prominent institution of Dorze public life.
Popular Culture in Africa: Findings and Conjectures
Authors: Fabian Johannes
Published: April 2006

Opening Paragraph

One effect of specialization in the field of African Studies has been to prevent or hinder the study of subjects which, by their very nature, demand interdisciplinary interests and competences. Emerging popular culture is such a field. Division of labor among various social sciences and between the social sciences and the humanities—late-comers to Anglo-American concerns with Africa—have long worked like a conjuring trick: making vast and vigorous expressions of African experiencede factoinvisible, especially to expatriate researchers. African scholars have been slow to denounce this state of affairs, perhaps out of an elitist need to set themselves apart from the loud and colorful bursts of creativity in music, oral lore, and the visual arts emerging from the masses.
From tidal swamp to inland valley: on the social organization of wet rice cultivation among the Diola of Senegal
Authors: Linares Olga F.
Published: April 2006

Introduction

Students of West African rice agriculture (cf. Dresch 1949, Mohr 1969) often distinguish between the Upper Guinea coast, where wet rice has been grown for centuries in permanent swamp fields recovered from the mangrove, and a more extensive area further inland, where the predominant form has been dry or mountain rice grown by shifting agriculturalists (fig. 1). The Diola of Senegal (Pélissier 1966, Linares 1970), the Balanta of Guinea Bissau (Espírito Santo 1949), and the Baga of coastal Guinea (Paulme 1957), belong to the first category. They transplant rice in inundated fields that are desalinated, diked, ridged and irrigated. In contrast, the Mande-speaking peoples of Sierra Leone and Liberia are mostly ‘upland’ farmers. They broadcast rice on rain-fed fields that are rotated and fallowed.
Misunderstandings Arising from the Use of the Term ‘Creole’ in the Literature on Sierra Leone
Authors: Skinner David , Harrell-Bond Barbara E.
Published: April 2006

Opening Paragraph

Throughout the growing body of literature on Sierra Leone a considerable degree of error has persisted over the use of the term ‘creole’ and the resultant confusion has led to repeated failure to describe accurately the society of the colony. This is not merely an academic problem. The very existence of such literature feeds back into the ‘collective representations’ of the society and has provided a false historical basis for the descriptions of the contemporary culture of the group who are referred to as creoles.
The fighting Nuer: primary sources and the origins of a stereotype
Authors: Johnson Douglas H.
Published: April 2006

Introduction

In the one hundred and forty years that the Nuer have been known to small audiences outside the Sudan they have almost invariably been presented as truculent and aggressive warriors. They appeared in the nineteenth century exploration literature as archetypical ‘savages’: naked, stubborn and warlike men who were compared to monkeys, to the monkeys' advantage (Baker 1867:60). In the early twentieth century they were thought to be an intractable problem that impeded the peaceful establishment and efficient running of a new colonial administration. In Sir Edward Evans-Pritchard's monographs Nuer feuds and raiding are described as central to the structural relations between Nuer sections and between the Nuer and their neighbours.
Village segmentation and class formation in southern Malaŵi
Authors: Kandaŵire J. A. K.
Published: April 2006

Opening Paragraph

This paper is about a problem which arises from James Clyde Mitchell's study of the Yao village in southern Malaŵi. When writing about the Yao, Mitchell drew our attention to their system of group segmentation which he portrayed as though it were perpetual in character (Mitchell 1952: 18-20). Here I analyse the implication of this process of group segmentation in a situation which is governed by administrative regulations that make it difficult for segmenting groups to spread as freely as they used to do before Britain colonised the country in 1891. What I want to argue is that owing to changes in population, against the background of fixed administrative or even political boundaries, group segmentation in southern Malaŵi is bound to throw into the open the old scars of structural inequality. Two types of facts are, therefore, required to carry out this demonstration: demographic and historical. Consequently, I divide this paper into three major sections: one in which I present figures showing population densities in Malaŵi in general, and in southern Malaŵi in particular; one in which I give a brief historical outline of Malaŵi; and one in which I attempt to show that from the available historical information we can discern processes that led to the formation of classes in Malaŵi and how these classes were simplified by the formation of the colonial situation which reduced, at one stroke, all Africans into a dependent classvis-à-visthe European colonisers. But despite this over-simplified picture of the two classes in the colonial situation, there is evidence at the local level which shows that as land is increasingly becoming scarce, relative to population growth, village disputes over land illuminate the traditional structure of inequalities. I hold the view that the inevitable result of the contradiction between population growth and land shortage is class formation.
The concept of spirit in Akwapim Akan philosophy
Authors: Minkus Helaine K.
Published: April 2006

Opening Paragraph

Studies of African religions almost invariably include detailed discussions of various categories of spirits. Rarely, however, is spirit considered in the abstract; spirits are described, but not the spiritual. This paper will explore the concept of sunsum, ‘spirit’, as it is employed throughout Akwapim Akan philosophy. Sunsum will be shown to be the central, unifying theme which integrates the various domains of Akwapim Akan thought. The distinction between the exclusively spiritual (ye sunsum) and the inspirited (wo sunsum) figures prominently in the ontology, epistemology and theory of causality and constitutes a major premise of the philosophy. The paper will conclude with the assertion that the universe in traditional Akwapim Akan thought is not divided into separate spiritual and material worlds but is most accurately regarded as one inspirited universe.
Curing what ails them: individual circumstances and religious choice among Zulu-speakers in Durban, South Africa
Authors: Rounds John C.
Published: April 2006

Opening Paragraph

Much attention has been given to the causes accounting for the rise of religious movements: inequality (Linton, 1943), racism (Lea, 1926; Sundkler, 1948), relative deprivation (Barber, 1941; Aberle, 1972), oppression (Lanternari, 1963), the colonial situation (Balandier, 1970), and white power (Ifeka-Moller, 1976) are among the factors which have been given prominence. These and other similarly ‘macro-social’ factors are very visible, especially from a distance. They can be, and often are, imagined to operate with general uniformity across entire social groups. This then invites the use of similarly general demographic measures to prove both the reality of the independent variable and its efficacy in accounting for the dependent variable – the rise of new churches and/or conversion to them.
The Supreme Being, divinities and ancestors in Igbo traditional religion: evidence from Otanchara and Otanzu
Authors: Ubah C. N.
Published: April 2006

Opening Paragraph

The subject of Igbo traditional religion has aroused a considerable amount of interest among scholars in the past few decades. The works of early ethnographers like Talbot (1926), Meek (1937) and Basden (1938) eloquently spelt out some of its principal themes. Among these are what we may refer to as the three major pillars of Igbo traditional religion, namely the Supreme Being, divinities and ancestors.

One of the problems with most of the existing studies is the tendency to generalize for the whole of Igboland on the basis of evidence which is valid for some Igbo areas only. Given the Igbo type of political system which is characterized by the existence of a very large number of autonomous communities, it is not surprising that there is a greater amount of heterogeneity in the religious system than is the case in the centralized kingdoms of pre-colonial Africa. To understand the diversity of Igbo religious beliefs and practices there is an imperative need for the study of the religious systems of specific Igbo communities.
Sacrifice and Social Structure among the Kuranko
Authors: Jackson Michael
Published: April 2006

In anthropological studies of African societies a recurring problem of analysis centres on the relationship between descent groupings and territorial units. A categorical distinction, such as Maine advanced (1861), between kinds of societies or groups based on either descent or locality is empirically spurious (Gluckman 1971: 85). Fortes has emphasised that the problem is one ‘of assigning an order of relative weight to the various factors involved in culture and in social organization, or alternatively of devising methods for describing and analyzing a configuration of factors so as to show precisely how they interact with one another’ (1953:25). Other writers have favoured this same move from reductionist either-or typologies to relativistic functional propositions, notably in analysing the modalities of descent (Lewis 1968; Goody 1969), of descent and affinity (Schneider 1968; Leach 1971), of kinship – and neighbourship (Gulliver 1971). But despite these developments, comparative analysis is still often based on crude correlations derived from an arbitrary and piecemeal codification of data (Hallpike 1971). My approach in this essay is guided by three structuralist propositions: descent and locality are (1) complementary principles, the significance of one being relative to the significance of the other, (2) mental —representations and tactical signs, rather than institutions sui generis, (3) variables within a transformational system, the system being susceptible to analysis at the level. of both organization and conceptualization.
Seasonal Hunger in Tropical Africa as a Cultural Phenomenon
Authors: Ogbu John U.
Published: April 2006

Introduction

In 1961 Marvin Miracle attempted to demonstrate that reports of ‘seasonal hunger’ in tropical Africa were to be discounted and that in fact regular ‘hunger periods’ did not occur. He based his argument on a definition of seasonal hunger which took into account only the calories people consumed. By his definition, ‘seasonal hunger’ can exist only if people consume fewer calories than they need in certain months of each year even though their total calorie intake over the year is adequate (Miracle, 1961: 277–88). He denied that there was sufficient evidence of any such shortfall to justify the F.A.O. statement (1958) that ‘pre-harvest food shortage is still a problem in many of the drier parts (of tropical Africa)’.
Generation Classes among the Mbeere of Central Kenya
Authors: Glazier Jack
Published: April 2006

Introduction

Age has represented in various ways a significant principle of social organization for the Mbeere of Kenya, one of the peoples of the North-eastern Bantu cluster, just as it has among numerous other peoples of East Africa. Traditionally a formal age organization comprised two groups: age-sets universally recruited from circumcised youth, and generation classes with constituent generation-sets. Informants' explanations of the age organization together with census and genealogical data clearly suggest that the recruitment principles and social processes within age-sets were independent of the recruitment principles and social processes characterizing generation classes and their generation-sets. The distinction between these two subsystems of the age organization is therefore more than an heuristic device.
The Work of Zion: An Analysis of an African Zionist Ritual
Authors: Kiernan J. P.
Published: April 2006

Opening Paragraph

African Zionist ritual is for the patient. The ambiguity is intended. Not only is Zionist ritual a healing rite but it makes demands on the patience of the participant. In the South African township of Kwa Mashu where African Zionists meet in small groups of from six to thirty people called Ibandla, i.e. a band, the meeting which takes place in one small room normally lasts for four or five of the hottest hours of the day. This is usually a Sunday. An occasional variant is to begin the meeting the previous midnight and continue into daylight. In either case, the most palpable feature of the meeting is its lack of urgency. It seems to meander indulgently from one unmanaged moment to the next and its atmosphere of unplanned relaxation leaves one with no expectation that it will ever end. The whole tenor of the meeting is therefore alien to the imposition of an organizational framework based on the division of activities into strict time intervals. Nevertheless time does intrude. In the course of the meeting the minister will more than once consult a watch ostentatiously placed before him on the table or he will interrupt activities publicly to enquire the time. Despite the general trend, therefore, some attempt is being made to measure and control the use of time. This is one way of stating the basic paradox of a Zionist meeting; despite an absence of overall control there are visible signs that control is somehow being exercised.
Inheritance and Women's Labour in Africa
Authors: Goody Jack , Buckley Joan
Published: April 2006

Opening Paragraph

Africa is notable for the extent to which women participate in cultivation. An examination of the contribution of men and women by means of ‘The Ethnographic Atlas (Ethnology, 1967) shows that women play the major part in cultivation in 45 per cent of societies in Africa as a whole, and in 53 per cent of sub-Saharan societies. We are concerned here with the contribution women make to cultivation (in pastoral as well as purely farming economies) and not to its over-all control, which is largely in the hands of men.
Meprises et admires: l'ambivalence des relations entre les Bacwa (Pygmees) et les Bahemba (Bantu)
Authors: Kazadi Ntole
Published: April 2006

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Un énorme travail a été réalisé sur les populations Pygmées du Zaïre. Dans ce domaine, l'ethnologie, l'anthropologie, la théologie africaine doivent beaucoup à J.-P. Hallet, à P. Schebesta, à C. M. Turnbull et á bien d'autres. Bon nombre de ces études ont diffusé et privilgié l'image prédominante du Pygmée nomadisant á travers la forêt, son milieu naturel. Cependant, elles ont occulté la connaissance et empêché l'investigation sur de nombreux autres groupes de Pygmées vivant loin de la forêt. En effet, pour Schebesta, qui fait de l'anthropométrie un critère privilégié, les seuls vrais Pygmées sont les Bambuti de la forêt de l'Ituri (1933: 63). Tous les autres ne seraient que des ‘Pygmoformes’ ou des ‘Pygmoïdes’, des ‘peuples métissés dont un croisement aura abâtardi les caractères de race et de culture’ (1940: 20). De nos jours, les critéres ont changé. Certains chercheurs se fondent sur le caractère polyphonique de la musique comme élément primordial dans la définition du Pygmée.
The Politics of Defection from an African Utopia
Authors: Barrett Stanley R.
Published: April 2006

Opening Paragraph

By definition Utopias are closed communities. They are established by people who believe that their basic goals—religious, social or otherwise—cannot be realized in conventional society. In order not to be contaminated by the mundane world, boundary-crossing is kept to a minimum. Members are discouraged from travelling outside the Utopias, and visitors are permitted only on a limited basis; usually, too, new members are unwelcome after a Utopia has been firmly established. Obviously Utopias vary in the extent to which the boundaries are closed (see Kanter 1972), but the above description is generally applicable. It is therefore understandable that a rapid increase in defection, and a concomitant upsurge in recruitment, should be regarded as a threat to the existence of a Utopia. From the point of view of the members, defectors have rejected the exact values that led to the Utopian movement, and thus threaten theirraison d'être. From the sociologist's perspective, a sharp increase in both defection and recruitment implies that the Utopia has begun to decline, because it cannot survive unregulated boundary-crossing.
Knowledge and belief in Suku thought
Authors: Kopytoff Igor
Published: April 2006

Opening Paragraph

This discussion grows out of an attempt to account for the presence among the Suku of Zaïre of a rather common but somewhat puzzling feature of African ‘ancestor cults.’ For all the importance of ancestors in African traditional life and thought, there is surprisingly little elaboration of the mode of their existence in the other world. In a masterly discussion of ‘ancestor worship’ in Africa, Fortes (1965: 126ff) notes this fact but does not attempt to explain it. To be sure, the issue is distinctly secondary to his main concern—the sociological matrix of ancestor cults. In sociological perspective, what matters about ancestors is their social role in this world, not their style of life in the next. This sociological perspective is in tune with African ethnographic fact: like Fortes, African informants are primarily interested in the social relationship of the ancestors with the living and they show little sympathy with the ethnographer's occasional curiosity about the details of the ancestors' own existence.
Interethnic contacts in Nigerian cities
Authors: Peil Margaret
Published: April 2006

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Nigeria is widely known as the African state where interethnic conflicts led to civil war. A great deal has been written to explain the ‘crisis’, as Nigerians prefer to call it, but there has been little study of the less newsworthy peace—the fact that large numbers of Nigerians in mixed communities get on fairly well together and have done so over a long period of time. In the Nigerian situation, a case can be made that intercommunal conflicts are really about economic and political power; ethnicity is only used to categorize people met in impersonal situations, or not met at all. Since the real game is power, it can also be shown that conflict is stronger at the top than at the bottom of the social system; the élites have more to gain than the masses by forwarding their ethnic group in relation to others. Of course, the élites have, on occasion, convinced the masses that benefits would be shared by all. Ethnic violence would not have been so well supported if this were not the case. The ordinary people have participated in riots, supported a civil war (on both sides), and most can be shown to harbour some prejudice toward members of other groups. But large numbers of them who migrate to the towns live peacefully with members of other groups, often find friends among them and, sometimes, wives or husbands.
‘Us’ and ‘them’: the International African Institute and the current crisis of identity in African Studies
Authors: Crowder Michael
Published: April 2006

In April 1986 British Africanists met to discuss the crisis facing African Studies in their country. The crisis was easily denned as one of lack of resources in universities where current cutbacks have particularly affected area studies; of the limited funds available to libraries specialising in African Studies; and of the severe reduction in the number of publishers willing to take on monographs relating to Africa, with the result that many scholars are ‘giving up all hope of being published'.1 Furthermore, lack of travel funds has meant that many Africanists teaching in Britain have not been to the continent of their study in seven years. So few new appointments have recently been made in the field of African Studies in British universities that, unless something drastic is done to reverse the trend, in fifteen years’ time there will be a sharp decline in the numbers actually engaged in African Studies as generations grow old and are not replaced.2 Students can see no future in pursuing African Studies at the postgraduate level and their teachers are in no position to advise even their most brilliant students that doctoral research will lead to an academic appointment. These developments have taken place in a context where those who run the government have lost or are losing interest in Africa, a continent which is seen increasingly as one of unending problems which they just wish would go away. Indeed, the whole crisis in African Studies, as described by some of the leading British Africanists that April, invited headlines in the respected weekly magazine West Africa: ‘African Studies in peril. Is the study of Africa in British universities dying?
Formal and Informal Rights to Land in Zimbabwe's Black Freehold Areas: a case-study From Msengezi
Authors: Cheater A. P.
Published: April 2006

INTRODUCTION

In 1930 the Land Apportionment Act created freehold areas exclusively for blacks, known as the ‘native purchase areas’. Forty-seven years later these sixty-six separate areas lost their legal identity when the Land Tenure Amendment Act consolidated them, and the formerly ‘European’ commercial farms, into the ‘general area’ distinct from the communally held ‘Tribal Trust Land’. Today, although the new Government has not yet touched Zimbabwe's land law, it has popularized new terms to describe these three categories: ‘rural farmers’ describes the peasantry in the communal lands; ‘small-scale commercial farmers’ locates freeholders in the former African purchase lands; and ‘large-scale commercial farmers’ are those whites– and handful of blacks – who work land in what used to be the ‘European area’. The small-scale commercial farmers, however, remain exclusively black. Thus we can talk of the African purchase lands as if they had not been affected by the Land Tenure Amendment Act of 1977.
Healing: cultural fundamentalism and syncreticism in Buganda
Authors: Obbo Christine
Published: April 2006

The article is based on a six-month survey of healers and sources of everyday medicine in and around Kampala, Uganda, during 1992. Four case studies of healers and their lives demonstrate the range of healing practice available to the sick or anxious. The emphasis is on the return to ‘our things’, to the techniques and beliefs of traditional Bugandan culture, in the face of ordinary people's poverty and the scarcity, cost or failure of biomedicine. But this ‘cultural fundamentalism’ is combined with practical syncretism, as the healers remain Muslims or Christians and readily recommend hospital treatment whenever it seems more appropriate.
The trade‐off between dispersability and longevity ‐ an important aspect of plant species diversity
Authors: Ehrlén J. , van Groenendael J.M.
Published: April 2006

Abstract. Local presence of plant species is determined by population colonizations and extinctions. All traits that influence the capacity of individuals to colonize patches and survive within patches, are therefore important for community diversity. Spatial models can explain the coexistence of species provided that the inferior competitor has a greater spatial mobility and thereby can avoid competition. We searched the literature for empirical evidence for such trade‐offs and included all available information on correlations between traits associated with the capacity to colonize and traits promoting the ability to survive.

A lower reproductive effort of a species is associated with a longer life span and a higher competitive ability. Morphological adaptations for dispersal are less common in species which better tolerate stress, that are better competitors or possess seed dormancy. Such patterns suggest that species that are good survivors may have a limited ability to colonize new patches and vice versa. A negative correlation between dispersability and longevity has important effects on the regional dynamics of single species as well as on the coexistence of species. From a conservation perspective differences in the colonization capacity among species imply that restoration of plant biodiversity must not only focus on conditions within patches, but also consider the spatial arrangement of patches in order to enable plants to bridge gaps in time and space.
Plant species richness in calcareous grasslands as affected by dispersability in space and time
Authors: Poschlod P. , Kiefer S. , Tränkle U. , Fischer S. , Bonn S.
Published: April 2006

Abstract. Species richness in calcareous grassland is discussed against the background of historical dispersal processes associated with traditional land‐use management such as grazing, but also the artificial establishment by hayseed. Important vectors in the traditionally man‐made landscape were sheep and cattle or other livestock such as goats. Calcareous grasslands were not only connected to each other but also to other habitats such as villages, forests, arable fields and heathlands by these vectors which could cover large distances (e.g. transhumance shepherding), which is not the case in the current man‐made landscape.

Species richness after restoration management of abandoned and afforested calcareous grasslands was predicted by using characters of dispersability in space and time. These were the persistence of the species in the vegetation and the diaspore bank after abandonment or afforestation and the dispersal capacity through wind and sheep. The results reveal that reintroduction of sheep grazing is necessary to reestablish the original species richness. The first validation of the prediction of the succession on clear‐cut sites and a comparison with data of species composition in abandoned quarries and the surroundings made it obvious that a species' own dispersal capacity in space is very low except for some well wind‐dispersed species. Therefore, it is recommended to include and to simulate dispersal processes in future management to be able to restore the original species richness.
Grazing Optimization: A Plea for a Balanced Perspective
Authors: Briske David D.
Published: April 2006

Compensatory plant growth may be a significant ecological process that minimizes the reduction of primary production in direct proportion to the severity of defoliation in some species and systems given the appropriate combination of environmental variables. However, the potential benefits of compensatory growth should not obscure the well—established ecological processes governing the sustainability of grazed systems in the face of large scale environmental degradation and a rapidly expanding human population. The sustainability of grazed systems is a more fundamental issue than grazing optimization.
Ecological Risk Assessment at The Regional Scale
Authors: Graham R. L. , Hunsaker C. T. , O'Neill R. V. , Jackson B. L.
Published: April 2006

Ecological risk assessments are used by policy makers and regulatory agencies for balancing and comparing ecological risks associated with environmental hazards. An approach for regional—scale ecological risk assessment is described and demonstrated by modeling environmental risks associated with elevated ozone in a forested region. The demonstration illustrates (1) how a regional—scale risk assessment might be done, (2) the importance of spatial characteristics in considering regional—scale risk, and (3) the necessity of considering terrestrial and aquatic linkages. Generic problems often encountered when doing regional assessments, the foremost of which is the frequent lack of region—specific information and spatial data, are also highlighted. In the demonstration, two levels of elevated ozone and five different at—risk regional features are considered (forest cover, forest edge, forest interior, landscape pattern, and lake water quality). The mechanism for impacts on these features is ozone—induced stress in coniferous trees, patches of which can then be killed by bark beetle attacks. A stochastic spatial model of land—cover change is developed to evaluate the risks or probabilities of significant changes in the selected ecological features as a consequence of these ozone—triggered beetle attacks. Risk to regional water quality of lakes is evaluated by linking the land—cover output from the spatial stochastic model to an empirical water—quality model that is sensitive to land—cover changes within a lake's watershed. The risk analysis shows that those environmental features that are sensitive to the location of coniferous forest (such as forest edge) are at risk of a significant change due to ozone—induced conifer mortality even though overall coniferous forest cover is only slightly affected. The analysis also suggests a high probability of changes in regional water quality of lakes as a consequence of location—specific forest—cover change.
Breeding Success of Hatchery and Wild Coho Salmon (Oncorhynchus Kisutch) in Competition
Authors: Fleming Ian A. , Gross Mart R.
Published: April 2006

The divergence of hatchery fish in traits important for reproductive success has raised concerns about their ability to rehabilitate wild populations, and the threat that their inevitable straying poses to biological diversity through introgression. We therefore undertook a study of the breeding competition and success of sea—ranched hatchery fish placed in direct competition with wild fish. Experiments using wild and hatchery coho salmo (Oncorhynchus kisutch) were conducted within a controlled stream channel, allowing selective manipulation of breeding competition and density. Hatchery fish, particularly males, were competitively inferior to wild fish, being less aggressive and more submissive. As a consequence, hatchery males were denied access to ovipositing females; they partook in fewer spawnings, held more distal positions in spawning hierarchies, and attained only an estimated 62% of the breeding success of wild males. By contrast, competition did not appear to inhibit hatchery females as overtly as males. Hatchery and wild females exhibited similar levels of aggressive behavior, however hatchery females did suffer greater delays in the onset of breeding, failed to spawn larger proportions of their eggs, and lost more eggs to nest destruction by other females. They averaged an estimated 82% of the breeding success of wild females. There was thus a sex bias in the breeding disadvantage of hatchery fish, with males suffering more than females. Furthermore, the breeding disadvantage was density dependent with the relative success of hatchery to wild fish declining with increasing density. These results imply that hatchery fish have restricted abilities to rehabilitate wild populations, and may pose ecological and genetic threats to the conservation of wild populations.
Regulation of Zooplankton Community Structure of an Acidified Lake by Chaoborus
Authors: Yan Norman D. , Keller Wendel , MacIsaac Hugh J. , McEachern Laurie J.
Published: April 2006

To test the hypothesis that the structure of zooplankton communities of acidified, fish—free lakes can be regulated by predation from larval Chaoborus, the rates of production of the principal prey species of Chaoborus in Swan Lake, a small, fish—less, acid lake near Sudbury, Canada, were compared with their estimated rates of consumption by Chaoborus. The production of Bosmina longirostris, the major crustacean zooplankter in the lake, rarely exceeded its apparent rate of loss to Chaoborus. In contrast, the production rate of Keratella taurocephala, the dominant rotifer in Chaoborus diets, virtually always exceeded the rate at which it was consumed. The unusually small contribution of Crustacea to total zooplankton biomass in the lake could be attributed to predation by Chaoborus. While Chaoborus can regulate zooplankton community structure in acidified, fish—free lakes, the frequency of occurrence of such control remains uncertain.
Integrating Ecological Concepts with Natural Resource Management of Southern Forests
Authors: Sharitz Rebecca R. , Boring Lindsay R. , Lear David H. Van , Pinder John E.
Published: April 2006

Natural resource management must integrate commercial development and use of forest resources with the maintenance of ecological values. The "New Perspectives" program of the U.S. Forest Service is responding to increased public environmental awareness and legislative mandates in placing a greater emphasis on ecosystem sustainability and non—traditional utilization of national forestlands. The forest of the southern United States is a complexity of associations developed along topographic and environmental gradients and shaped by natural disturbances and anthropogenic perturbations. It is highly fragmented as a result of past clearing for agriculture and timber harvesting and patterns of land ownership. Southern forests, in contrast to those in other regions, are mostly privately owned. This fragmentation is being maintained by current urbanization and industrialization as the population of the south increases. Our purpose is to identify ecological themes and concepts compatible with the stewardship philosophy of the Forest Service's New Perspectives that can be applied to the management of sustainable southern forest resources. Of special concern are the maintenance of biological diversity, watershed and water quality protection, and the assessment of regional land—use effects on the integrity of forest ecosystems and on continued forest productivity. Ecological principles must be integrated with natural resource management on landscape and regional scales to achieve sustainability of the southern forest ecosystem.
Watershed Ecosystem Analysis as a Basis for Multiple‐Use Management of Eastern Forests
Authors: Hornbeck James W. , Swank Wayne T.
Published: April 2006

There is ever—increasing competition for the many uses and natural resources of forests in the eastern United States. Multiple—use management has long been a stated goal for these forests, but application has been problematic and seldom satisfactory to all users. There is a need to incorporate more science into management decisions for Eastern forests, and thereby convincingly demonstrate to forest managers and the public why certain combinations of uses may or may not be compatible. One proven approach for doing this is to use watershed ecosystem analysis. Small watersheds, usually <100 ha in area, serve as a convenient ecosystem for studying how forests function in terms of cycling energy, nutrients, and water. Results of these studies allow assessments of forest health and productivity, and evaluations of impacts of both natural and human—related disturbances. This paper provides illustrations of how watershed ecosystem analysis can be used to study the effects of current harvesting practices, acidic deposition, and past land use. The paper also shows how recommendations for land use are derived from watershed ecosystem analysis, and how they are put into practice.
Ecological Risks of Transgenic Plants: Effects of Spatial Dispersion on Gene Flow
Authors: Manasse Robin S.
Published: April 2006

The spread of advantageous transgenic genes from crop plants into wild and weedy relatives is a potential ecological problem. The available theory indicates that the spread of a gene, over space and time, will depend in part on the relative selective advantage of that gene, and in part on gene flow, or the probability distribution of gene movement from source to target plants within a single generation. Risk assessment will require knowledge of both. This paper describes an empirical investigation of the effect of spatial dispersion on gene flow in Brassica campestris, utilizing a system of wild genotypes for target plants, and agronomic genotypes with a marker gene for source plants. I have found that gene flow can be reliably modeled with an exponential probability density function, and that the mean of that distribution can vary with the spatial dispersion of plants. Two—dimensional arrays of plants had lower mean gene dispersal distance than did one—dimensional arrays. In contrast, the degree of clumping and the size of patches of plants in my experiments had no effect on gene flow. However, I found an increase in mean gene dispersal distance with increased distance between clumps of plants, or between individual plants in one year. These results imply that large isolation distances accompanied by a rare long—distance pollination event will ultimately increase the risk of gene spread.
Water Uptake in Woody Riparian Phreatophytes of the Southwestern United States: A Stable Isotope Study
Authors: Busch David E. , Ingraham Neil L. , Smith Stanley D.
Published: April 2006

Alluvial forest associations are often dominated by woody phreatophytes, plants that are tightly linked to aquifers for water uptake. Anthropogenic hydrological alterations (e.g., water impoundment or diversion) are of clear importance to riparian ecosystem function. Because decreased frequency of flooding and depression of water tables may, in effect, sever riparian plants from their natural water sources, research was undertaken to determine water uptake patterns for the dominant native and introduced woody taxa of riparian plant communities of the southwestern United States. At floodplain study sites along the Bill Williams and lower Colorado Rivers (Arizona, USA), naturally occurring D and 18O were used to distinguish among potential water sources. Isotopic ratios from potential uptake locations were compared to water extracted from the dominant woody taxa of the study area (Populus fremontii, Salix gooddingii, and Tamarix ramosissima) to elucidate patterns of water absorption. Isotopic composition of water obtained from sapwood cores did not differ significantly from heartwood or branch water, suggesting that heartwood water exchange, stem capacitance, and phloem sap mixing may be inconsequential in actively transpiring Salix and Populus. There was evidence for close hydrologic linkage of river, ground, and soil water during the early part of the growing season. Surface soils exhibited D enrichment due to cumulative exposure to evaporation as the growing season progressed. Isotopic ratios of water extracted from Populus and Salix did not exhibit isotopic enrichment and were not significantly different from groundwater or saturated soil water sources, indicating a phreatophytic uptake pattern. Associations of isotopic ratios with water relations parameters indicated high levels of canopy evaporation and possible use of moisture from unsaturated alluvial soils in addition to groundwater in Tamarix.
Environmental Variation and the Persistence of Small Populations
Authors: Stacey Peter B. , Taper Mark
Published: April 2006

Understanding the factors that determine the continued survival of small populations is a central problem in conservation biology. The Acorn Woodpecker (Melanerpes formicivorus) naturally occurs in small, isolated populations throughout much of the American Southwest. In spite of this distributional pattern, the species is neither rare nor endangered. Thus it appears to have successfully "solved" the problems to the problems of habitat fragmentation. We used data from a 10—yr field study and simulation models to examine the effects of environmental stochasticity on population survival times. All simulated woodpecker populations went extinct within 49 yr, and the median survival time was only 16 yr. However, when immigration was allowed, persistence times greatly increased; with an immigrant rate of only five individuals per year, most populations lasted >1000 yr. The results of this and other analyses suggest that this population persists only because it is part of a larger "metapopulation," and because it is regularly rescued from extinction by immigration from other, independently varying, populations. This finding has important implications for the development of management strategies designed to preserve small populations that are faced with fragmented distributional patterns and high levels of environmental variation.