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This study explores temporal dynamics within grassland and Miombo woodland ecosystems in southern Mozambique and their potential coupling to hydro-climate change during the late-Holocene period. Pa...

Savannas are dynamic and heterogeneous environments with highly variable vegetation that responds to a multitude of interacting drivers. Rainfall, soils, herbivory, fire and land use all effect land cover in savannas. In addition, savannas have a long history of human use. Setting management goals is therefore complex. Understanding long-term variability in savannas using palaeoecology provides a context for interpretation of recent changes in vegetation and can help to inform management based on acceptable or historical ranges of variability. In this article, we review and synthesise palaeoecological data from southern African savannas and use resilience theory as a framework for structuring and understanding of vegetation dynamics in savannas. We identify thresholds between alternate stable states, which have different ecological properties, suites of species and ecosystem services. Multi-proxy palaeoecological records can assist in identifying alternate states in savanna vegetation, as well as showing how different drivers (fire, herbivory, nutrients and climate) interact to drive transitions between states. Conservation implications: The ecological thresholds identified from palaeoecological data can be used to inform the development of management thresholds, known as thresholds of potential concern. Thresholds of potential concern are designed to facilitate or impede transitions between states by manipulation of those variables (e.g. fire and herbivory) that can be controlled at the landscape scale.

East African landscapes today are the result of the cumulative effects of climate and land-use change over millennial timescales. In this review, we compile archaeological and palaeoenvironmental data from East Africa to document land-cover change, and environmental, subsistence and land-use transitions, over the past 6000?years. Throughout East Africa there have been a series of relatively rapid and high-magnitude environmental shifts characterised by changing hydrological budgets during the mid- to late Holocene. For example, pronounced environmental shifts that manifested as a marked change in the rainfall amount or seasonality and subsequent hydrological budget throughout East Africa occurred around 4000, 800 and 300 radiocarbon years before present (yr BP). The past 6000?years have also seen numerous shifts in human interactions with East African ecologies. From the mid-Holocene, land use has both diversified and increased exponentially, this has been associated with the arrival of new subsistence systems, crops, migrants and technologies, all giving rise to a sequence of significant phases of land-cover change. The first large-scale human influences began to occur around 4000?yr BP, associated with the introduction of domesticated livestock and the expansion of pastoral communities. The first widespread and intensive forest clearances were associated with the arrival of iron-using early farming communities around 2500?yr BP, particularly in productive and easily-cleared mid-altitudinal areas. Extensive and pervasive land-cover change has been associated with population growth, immigration and movement of people. The expansion of trading routes between the interior and the coast, starting around 1300?years ago and intensifying in the eighteenth and nineteenth centuries CE, was one such process. These caravan routes possibly acted as conduits for spreading New World crops such as maize (Zea mays), tobacco (Nicotiana spp.) and tomatoes (Solanum lycopersicum), although the processes and timings of their introductions remains poorly documented. The introduction of southeast Asian domesticates, especially banana (Musa spp.), rice (Oryza spp.), taro (Colocasia esculenta), and chicken (Gallus gallus), via transoceanic biological transfers around and across the Indian Ocean, from at least around 1300?yr BP, and potentially significantly earlier, also had profound social and ecological consequences across parts of the region.\ud \ud Through an interdisciplinary synthesis of information and metadatasets, we explore the different drivers and directions of changes in land-cover, and the associated environmental histories and interactions with various cultures, technologies, and subsistence strategies through time and across space in East Africa. This review suggests topics for targeted future research that focus on areas and/or time periods where our understanding of the interactions between people, the environment and land-cover change are most contentious and/or poorly resolved. The review also offers a perspective on how knowledge of regional land-use change can be used to inform and provide perspectives on contemporary issues such as climate and ecosystem change models, conservation strategies, and the achievement of nature-based solutions for development purposes.

The conceptual framework of biocultural heritage allows for new approaches to heritage, nature conservation, landscape planning and development goals, providing means to negotiate management goals in these areas, and in certain cases, also to combine them. By reviewing knowledge from the literature, this paper develops a new conceptual framework of biocultural heritage. Five "elements" constitute biocultural heritage in this framework. First, ecosystem memories denote biophysical properties, non-human organisms and agents changed or affected directly or indirectly by humans. Second, landscape memories represent tangible materialised human practice and semi-intangible ways of organising landscapes, such as built environments and archaeological sites, and settlement systems linked to user and property rights. Third, place-based memories refer to intangible living features of human knowledge and communication expressed in know-how, place names, orature, arts, ideas and culture, received, preserved and transmitted over generations. The fourth element, integrated landscape analysis, denotes a toolbox and a conceptual framework for knowledge construction and landscape management. The final fifth element of biocultural heritage, stewardship and change, represents the activity of, and ability in, exploring memory reservoirs of biocultural heritage for transferring knowledge to policy and management and for shaping collaborative initiatives. To illustrate the framework, this paper then presents a study from the village Angersjo located in the boreal forest in central Sweden. As conclusion, we suggest that the approach - with improvements and modifications - represents an operational joint framework for exploring and managing biocultural heritage, drawing on the past for envisioning the future.

The present day distribution of Miombo savanna-woodland in Mozambique has been attributed to an expansion due to the clearing of original coastal forests through agriculture and use of fire. Here, we test this hypothesis using palaeoecological data from Lake Nhauhache, situated in the Vilankulo region. Our analysis shows that Brachystegia, one of the main constituents of the Miombo, has varied over time, and its variability seems to be driven by hydrological changes related to climatic variability rather than by land-use changes. The analyses show that Brachystegia was most common during ad 200–700 when a marshy forest/shrub community was dominant. After ad 700, this community changes to a dominance of Syzygium and Fagara linked to gradually rising water levels. Brachystegia remains in low abundance and fluctuating over time. From ad 1000, a general decline in trees/shrubs in favour of grasses concurs with an increase in grass pollen (possibly cereal) and charcoal, most probably as a result of farming activities. The decline in tree taxa was probably exacerbated by periodic droughts after c.ad 1200 as indicated by the diatom assemblage. In the period ad 1700 to late 1800, arboreal pollen is well represented, and this is concurrent with the diatom record suggesting high lake levels.

This paper discusses changing patterns of resource utilisation over time in the locality of Chibuene, Vilankulos, situated on the coastal plain of southern Mozambique. The macroscopic charcoal, bone and shell assemblages from archaeological excavations are presented and discussed against the off-site palaeoecological records from pollen, fungal spores and microscopic charcoal. The Chibuene landscape has experienced four phases of land use and resource utilisation that have interacted with changes in the environment. Phase 1 (a.d. 400–900), forest savanna mosaic, low intensity cattle herding and cultivation, trade of resources for domestic use. Phase 2 (a.d. 900–1400), forest savanna mosaic, high intensity/extensive cultivation and cattle herding. Phase 3 (a.d. 1400–1800), savanna woodland and progressive decrease in forests owing to droughts. Decline of agricultural activities and higher reliance on marine resources. Possible trade of resources with the interior. Phase 4 (a.d. 1800–1900), open savanna with few forest patches. Warfare and social unrest. Collapse of trade with the interior. Decline in marine resources and wildlife. Loss of cattle herds. Expansion of agriculture locally and introduction of New World crops and clearing of Brachystegia trees. The study shows the importance of combining different environmental resources for elucidating how land use and natural variability have changed over time.

Invasion ecology has made rapid progress in recent years through synergies with landscape ecology, niche theory, evolutionary ecology and the ecology of climate change. The palaeo-record of Holocene invasions provides a rich but presently underexploited resource in exploring the pattern and process of invasions through time. In this paper, examples from the palaeo-literature are used to illustrate the spread of species through time and space, also revealing how interactions between invader and invaded communities change over the course of an invasion. The main issues addressed are adaptation and plant migration, ecological and evolutionary interactions through time, disturbance history and the landscape ecology of invasive spread. We consider invasions as a continuous variable, which may be influenced by different environmental or ecological variables at different stages of the invasion process, and we use palaeoecological examples to describe how ecological interactions change over the course of an invasion. Finally, the use of palaeoecological information to inform the management of invasions for biodiversity conservation is discussed. © 2008 Springer Science+Business Media B.V.

The long‐term responses of vegetation to climate variability are of relevance for predicting present and future vegetation change, and have implications for the management of savanna and riparian ecosystems. This paper explores the links between regional rainfall, hydrology and vegetation dynamics in the savannas and riverine forests of the lower Limpopo Valley, southern Africa, from 800 AD to the present, reviewing palaeoecological data (fossil pollen, spores, diatoms and lithology) from several hydrological systems in Kruger National Park (KNP), South Africa and Limpopo National Park (PNL), Mozambique. The PNL–KNP records show that riverine arboreal taxa expanded during wetter periods, including 800–1400 AD and after 1800 AD. Between 1400 and 1800 AD, grasses, savanna taxa and generalist taxa were favored over riparian taxa, a change that is linked with the onset of dry spells in the region (corresponding to the so-called Little Ice Age). The most extreme drought events around 1700 AD resulted in a marked decline of riparian forest taxa near Lake Mapimbi, KNP. In contrast, many water-scarce sequences away from the riverine environment, such as Radio Pan, Mafayeni Pan, Malahlapanga Pan and Lake Makwadzi show stable grassland vegetation throughout the last 1200 years. The results demonstrate the resilience of the grassland–savanna ecosystems to projected climate change with warmer and overall drier climate. The riverine forests are predicted to be more vulnerable especially as more extreme weather events are projected.

In this paper, we review the potential of biocultural heritage in biodiversity protection and agricultural innovation in sub-Saharan Africa. We begin by defining the concept of biocultural heritage into four interlinked elements that are revealed through integrated landscape analysis. This concerns the transdisciplinary methods whereby biocultural heritage must be explored, and here we emphasise that reconstructing landscape histories and documenting local heritage values needs to be an integral part of the process. Ecosystem memories relate to the structuring of landscape heterogeneity through such activities as agroforestry and fire management. The positive linkages between living practices, biodiversity and soil nutrients examined here are demonstrative of the concept of ecosystem memories. Landscape memories refer to built or enhanced landscapes linked to specific land-use systems and property rights. Place memories signify practices of protection or use related to a specific place. Customary protection of burial sites and/or abandoned settlements, for example, is a common occurrence across Africa with beneficial outcomes for biodiversity and forest protection. Finally, we discuss stewardship and change. Building on local traditions, inclusivity and equity are essential to promoting the continuation and innovation of practices crucial for local sustainability and biodiversity protection, and also offer new avenues for collaboration in landscape management and conservation.

Effective wildlife management needs historical data on herbivore abundance and its interactions with vegetation, climate and disturbance over longer time periods that is available through observational and archive data. Spores specific to herbivore dung provide a potential source of information on past herbivore abundances. This paper sets out to evaluate the potential of fungal spores as environmental indicators and in particular the use of coprophilous fungi in understanding past herbivore densities and their impact on the savanna landscape of Kruger and Limpopo National Parks (South Africa and Mozambique). Spore assemblages from six sedimentary cores are analysed and compared with the pollen data. Spores of coprophilous fungi, Coniochaeta cf ligniaria, and Sordariaceae in particular provide a valuable source of information about past herbivore densities. The spore assemblages of investigated localities show historical fluctuations in herbivore abundance. Peaks in wild/domestic herbivore densities can be seen, on a local scale from 800 to 900 AD and another at 1400 AD, however, these cannot be linked with any significant changes in vegetation. The last 200–300 years have seen an increased abundance of herbivores in the Limpopo floodplain sites, particularly domestic cattle. There is no clear correspondence between changes in herbivore abundance and local vegetation in this period or the 20th century. However, domestic cattle, together with wild herbivores, probably contributed to creating a mosaic type of landscape with heterogeneous tree cover.

This paper compares vegetation dynamics at two sites in the savanna landscape of Limpopo National Park (PNL), Mozambique. In order to test the relationship between vegetation cover and hydrology, nutrient availability and disturbance from grazing and fire over the last 1,200 years at local (100 m2) scales, we use palaeoecological data (i.e. pollen assemblages, charcoal abundance, C/N ratio, stable isotopes and herbivore-associated spore abundance). Two pans governed by similar rainfall regimes (on average 600 mm/year) but different hydrologies are compared. Chixuludzi Pan is responsive to the Limpopo River and is more water rich than Radio Pan, which is situated in a dry landscape with little surface water. The analysis suggests that in savannas where water is scarce, the recruitment of woody taxa is constrained mainly by the availability of underground water. In the Radio Pan sequence, the present grassland savanna has been stable throughout the time studied. In contrast, the Chixuludzi Pan savanna landscape where local hydrology, due to the proximity of Limpopo River, allows for a higher water availability the relationship between grass-arboreal pollen suggests a greater variability in vegetation cover, and other factors such as grazing, herbivory and nitrogen availability are important as controlling mechanisms for woody cover. The historical depth of the analysis enables a sub-hierarchy of local scale process to be identified, in this case local hydrology. Local water availability is shown to override the effect of regional rainfall and, in turn, to control the influence of other local scale factors such as nutrients and grazing.

This paper explores the general correlations between fire and grass/tree relationships, as represented by fossil charcoal and pollen, from different vegetation types in the savanna ecosystems of the neighbouring Kruger (KNP) and Limpopo (PNL) national parks. Our analysis suggests that the basic presumption that fire is a main driver of vegetation dynamics in the savanna ecosystem by suppressing tree seedlings and encouraging grasses needs to be re-examined. An improved approach is to understand how fire may act both as a negative and positive feedback in different vegetational phases and both as a driver and responder in transitions between phases. The correlation between arboreal pollen (AP) percentages and charcoal influx suggests that in the grassland phase (< 5% AP), fire acts as a driver of woody recruitment and as a positive feedback, i.e. potentially driving the system to shift into a savanna phase. In the savanna phase (5—10% AP) fire limits woody recruitment and acts as a negative feedback in maintaining the savanna. Thus, in the savanna phase other factors than fire alone drive the transition from savanna to woodland-forest. In the riparian phase, where evidence of farming is present particularly from AD 1600 onwards, fire appears to facilitate tree recruitment where AP ranges between c. 10 and 20% AP. Though a decline in AP abundance can be seen contemporaneously with charcoal peaks, our analysis suggests that overall, human-induced fires do not seem to have a negative impact on woody cover. Our results have implications for fire management as riparian-dominated phases and savannas with a sufficient woody cover are less sensitive to changes in fire policies than open grasslands that may, with a change in fire frequency, change into another state.

Resilience theory suggests that ecosystems can persist for long periods, before changing rapidly to a new vegetation phase. Transition between phases occurs when ecological thresholds have been crossed, and is followed by a reorganization of biotic and environmental interactions, leading to the emergence of a new vegetation phase or quasistable state. Savannas are dynamic, complex systems in which fire, herbivory, water and nutrient availability interact to determine tree abundance. Phase and transition has been observed in savannas, but the role of these different possible drivers is not always clear. In this study, our objectives were to identify phase and transition in the fossil pollen record, and then to explore the role of nitrogen and fire in these transitions using d15N isotopes and charcoal abundance. We present palaeoenvironmental data from the Kruger National Park, South Africa, which show transition between grassland and savanna phases. Our results show transition at the end of the ninth century A.D. from a nutrient and herbivore-limited grazing lawn, in which fire was absent and C4 grasses were the dominant and competitively superior plant form, to a water-, fire and herbivory-limited semi-arid savanna, in which C4 grasses and C3 trees and shrubs co-existed. The data accord with theoretical frameworks that predict that variability in ecosystems clusters in regions of higher probability space, interspersed by rapid transitions between these phases. The data are also consistent with the idea that phase transitions involve switching between different dominant driving processes or limiting factors.

In the coastal lowlands of Mozambique, an expansion of savannas at the cost of forests has been attributed to anthropogenic influence. There are few investigations that have studied vegetation dynamics over the long term. Pollen analysis from two sedimentary cores in the Chibuene area, 7 km south of Vilanculos presented in this paper show that the coastal area 1600 years ago consisted of a mosaic of forests, Miombo woodlands and grasslands. The data also show that the area supported extensive forests in the past until AD 1400—1600 when the forests declined dramatically. Changing settlement patterns, as suggested from archaeological excavations, cannot be correlated with the forest decline and the charcoal abundance, in the sedimentary cores does not suggest an intensification of farming. Instead the decline of forests appears to be temporally correlated with a prolonged period of repeated dry spells associated with the `Little Ice Age', which caused a shift in vegetation whereby typical forest species as Trema, Celtis and Moraceae were outcompeted on account of the droughts. This study challenges rooted assumptions about the cause of decline of forests in the coastal region. It also suggests that the forest fragments present on the Mozambique coast today are naturally subject to threat from climatic stress and as such are highly sensitive areas to future climate change.

Understanding the interplay between climatic and anthropogenic factors is a major challenge in palaeo-ecology. In particular, it is often difficult to distinguish anthropogenic and “natural” fire in the charcoal record. In this paper, analysis of fossil pollen, charcoal, diatoms and isotopic evidence from Mapimbi, a small lake in the Kruger National Park, South Africa, suggests that for most of the past ca. 700 years, the riverine gallery forests surrounding Mapimbi were primarily influenced by climate, and benefited during warmer, wetter periods. The transitions between four, statistically different phases in the time-series data coincide with regional climate records previously constructed from speleothem data, and are consistent with the transition from the medieval warm period ending in the 14th century a.d. to the cooler, drier conditions prevailing during the little ice age of ca. a.d. 1400–1800. The data also suggest a period of significant, anthropogenic influence after a.d. 1800, when maize was grown and the incidence of localised fires increased. An increase in woody cover in recent decades may be associated with the management of the area by Kruger National Park. A decline in cultivation occurred in the end of the 20th century linked with changes in socio-political organisation.

In this contribution, we review long-term (millennial-decadal scale) river-flow changes, climate interactions, and interlinkage with vegetation dynamics, as well as society and policy, focusing on ...

This paper presents the results of a consensus-driven process identifying 50 priority research questions for historical ecology obtained through crowdsourcing, literature reviews, and in-person workshopping. A deliberative approach was designed to maximize discussion and debate with defined outcomes. Two in-person workshops (in Sweden and Canada) over the course of two years and online discussions were peer facilitated to define specific key questions for historical ecology from anthropological and archaeological perspectives. The aim of this research is to showcase the variety of questions that reflect the broad scope for historical-ecological research trajectories across scientific disciplines. Historical ecology encompasses research concerned with decadal, centennial, and millennial human-environmental interactions, and the consequences that those relationships have in the formation of contemporary landscapes. Six interrelated themes arose from our consensus-building workshop model: (1) climate and environmental change and variability; (2) multi-scalar, multi-disciplinary; (3) biodiversity and community ecology; (4) resource and environmental management and governance; (5) methods and applications; and (6) communication and policy. The 50 questions represented by these themes highlight meaningful trends in historical ecology that distill the field down to three explicit findings. First, historical ecology is fundamentally an applied research program. Second, this program seeks to understand long-term human-environment interactions with a focus on avoiding, mitigating, and reversing adverse ecological effects. Third, historical ecology is part of convergent trends toward transdisciplinary research science, which erodes scientific boundaries between the cultural and natural.

A sustainable livelihood framework is used to analyse livelihood security, vulnerability and resilience in the village of Chibuene, Vilanculos, southern Mozambique from a historical and contemporary perspective. Interviews, assessments, archaeology, palaeoecology and written sources are used to address tangible and intangible aspects of livelihood security. The analysis shows that livelihood strategies for building resilience, diversification of resource use, social networks and trade, have long historical continuities. Vulnerability is contingent on historical processes as long-term socio-environmental insecurity and resultant biodiversity loss. These contingencies affect the social capacity to cope with vulnerability in the present. The study concludes that contingency and the extent and strength of social networks should be added as a factor in livelihood assessments. Furthermore, policies for mitigating vulnerability must build on the reality of environmental insecurity, and strengthen local structures that diversify and spread risk.