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Syzygium guineense ssp. huillense, a typical species of the Parinari capensis grasslands (photo: M. Finckh).
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... The Cubango-Okavango River basin is a mosaic of natural forest landscapes, low-input agricultural systems, and patches of intensive highinput agriculture. Rural settlements cluster along the river, a limited road network, and scattered boreholes (Revermann & Finckh, 2013). ...
People's preferences influence national priorities for economic development and ecological integrity. Often policy makers and development agents base their actions on unclear assumptions about such preferences. This paper explores rural citizens' preferences for economic and ecological development outcomes and how they differ within and between communities. We collected data from three purposely selected communities representing dominant social-ecological systems in the transboundary Cubango-Okavango River Basin in southern Africa. We used contingent ranking survey experiments, which are a novel methodological advance in policy related research. This included a qualitative experimental design process that provided a broad framing underpinning the research. The contingent ranking itself allowed us to simultaneously assess (i) respondents' priorities for development domains; and (ii) respondents' preferences for the ordering of outcomes in diverse domains. We found relatively strong preference homogeneity within and between communities. Economic development was given high priority across all communities. At the same time, all communities expressed a high preference for a healthy river system providing stable water quality and quantity. This does not mean that our respondents prioritized nature conservation. They showed low preferences for preserving biodiversity and forests that provide fewer local benefits. This is of high governance relevance. The results point at development domains where policy makers can most likely expect stronger buy-in from citizens. Understanding citizens' preferences helps to better align national development priorities with what citizens want.
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... Based on this data, classifications for local study sites based on numerical classification approaches have been published (Revermann and Finckh 2013a;Wallenfang et al. 2015) and a first classification of the terrestrial vegetation of the entire Cubango Basin was elaborated (Revermann et al. 2018a). Olson et al (2001) which are largely based on the vegetation maps of Barbosa (1970) and White (1983), (b) Vegetation map produced for the same area by The Future Okavango project based on unsupervised classification of land surface phenology metrics derived from 16-day MODIS EVI time series from the years 2000-2011 ) and interpreted using the information of vegetation plots stored in the vegetation database of the Okavango Basin (Revermann and Finckh 2013b;Revermann et al. 2016a). For an explanation of the vegetation units depicted in the maps please refer to the original publications The vegetation database of the Okavango Basin was also the foundation to produce a first vegetation map based on quantitative ground data for the Okavango Basin ( Fig. 6.2b Revermann and Finckh 2013b;Stellmes et al. 2013) and allowed modelling the α-diversity of vascular plants for the same region (Revermann et al. 2016b). ...
... Olson et al (2001) which are largely based on the vegetation maps of Barbosa (1970) and White (1983), (b) Vegetation map produced for the same area by The Future Okavango project based on unsupervised classification of land surface phenology metrics derived from 16-day MODIS EVI time series from the years 2000-2011 ) and interpreted using the information of vegetation plots stored in the vegetation database of the Okavango Basin (Revermann and Finckh 2013b;Revermann et al. 2016a). For an explanation of the vegetation units depicted in the maps please refer to the original publications The vegetation database of the Okavango Basin was also the foundation to produce a first vegetation map based on quantitative ground data for the Okavango Basin ( Fig. 6.2b Revermann and Finckh 2013b;Stellmes et al. 2013) and allowed modelling the α-diversity of vascular plants for the same region (Revermann et al. 2016b). ...
Spatial information about plant species composition and the distribution of vegetation types is an essential baseline for natural resource management planning. In Angola, the first countrywide vegetation map was elaborated by Gossweiler in 1939. Subsequently, Barbosa published a revised map with much higher detail in 1970 and his work has remained the main reference for the vegetation of Angola until today. However, these early maps were expert drawn and were not based on systematic surveys. Instead, the delimitation of vegetation units was based on many years of field observations and also incorporated results of local studies carried out by other authors. In spite the rich history of the scientific exploration of Angola’s vegetation in colonial times, quantitative and plot based studies were rare. After the end of the armed conflict, new vegetation surveys making use of new methodological developments in numerical approaches to vegetation classification in combination with modern remote sensing imagery have provided spatial information of unprecedented detail. However, vast areas of the country still remain seriously understudied. At the same time, sustainable land management strategies are urgently needed due to the increasing pressure on natural resources driven by socio-economic development and global change, thus calling for a new era of vegetation surveys that will enable data-based landuse and conservation planning in Angola.
... At this time of year masses of cold dry air from southern latitudes intrude into south-central Africa (Tyson and Preston-Whyte 2000). As depressions accumulate confluent cold air, the undulating topography of the Angolan highlands facilitates frequent radiation frost especially in valleys (Revermann and Finckh 2013;Finckh et al. 2016). Up to 44 frost events per dry season (with a minimum temperature of −7.5 °C) were recorded by Finckh et al. (2016), with a temperature span of up to 40 degrees within 12 h. ...
... Tree species relocated their woody biomass and regenerative buds belowground at the expense of growth height and were thus able to cope with frost and fire prone sites (White 1976;Maurin et al. 2014;Finckh et al. 2016). Even shallow soil depths of less than 10 cm are sufficient to alleviate thermic stresses (Revermann and Finckh 2013). The high number of tropical genera and families that contribute to the suffrutex flora show how successful this strategy is for frost sensitive and fire susceptible taxa, in order to survive the adverse conditions of the open grasslands. ...
A small-scale mosaic of miombo woodlands and open, seasonally inundated grasslands is a typical aspect of the Zambezian phytochorion that extends into the eastern and central parts of Angola. The grasslands are home to so-called ‘underground trees’ or geoxylic suffrutices, a life form with massive underground wooden structures. Some (but not all) of the geoxylic suffrutices occur also in open woodland types. These iconic dwarf shrubs evolved in many plant families under similar environmental pressures, converting the Zambezian phytochorion into a unique evolutionary laboratory. In this chapter we assemble the current knowledge on distribution, diversity, ecology and evolutionary history of geoxylic suffrutices and suffrutex-grasslands in Angola and highlight their conservation values and challenges.
... This case refers to the Namibian Kavango regions characterized by a semi-arid climate with an annual precipitation of approximately 600 mm (Weber, 2013). Although a significant proportion of the Okavango basin is still covered with primary forest of different types (Revermann & Finckh, 2013) more than 70 percent of the riverine vegetation has been lost over the past few decades (RoN, 2004). The expansion of agricultural fields is the main driver of deforestation (Pröpper et al., 2010). ...
Ecosystems around the world generate a wide range of services. Often, there are trade-offs in ecosystem service provision. Managing such trade-offs requires governance of interdependent action situations. We distinguished between (1) enhancing action situations where beneficiaries create, maintain, or improve an ESS and (2) appropriation action situations where actors subtract from a flow of ESS. We classified ESSs in order to identify focal action situations and link them to ESS governance types which are likely to strengthen sustainable ecosystem management. The classification is applied to six forest cases in Asia, Africa and Latin America. Our results confirm that ecosystem management, which more strongly supports the provision of public goods and common pool resources, is often under strong pressure to be transformed into systems that mainly provide private goods. This can be partly explained by incentive constellations in the action situations of public goods and common pool resources. Therefore, governance has to be adapted to specific ESSs. ESS governance needs to identify institutions which best fit to different ESSs and to harmonize them for all the ESSs provided by the system. Our approach helps to understand why institutions fail or succeed in maintaining ESSs.
... Miombo woodlands show variations in terms of density and species composition throughout the region, with diff erences in species composition being more evident at local scale. Local abiotic conditions and changes from Brachystegia spiciformis to Julbernardia paniculata communities, together with various other woody species, may also infl uence the stand structure and composition of the woodlands (Revermann & Finckh, 2013). Signs of tree damage caused by fi re, woodcutting, and/or agriculture activity were also documented; this is a stark reminder that fi re frequency, together with other human disturbance, plays a major role in miombo woodland dynamics, aff ecting physical structure, composition of species, and also woodland recovery following disturbance (Chidumayo, 2002;Furley et al., 2008). ...
... obovata woodlands, belongs to the Zambezian Baikiaea woodlands eco-region, which forms a mosaic of Baikiaea plurijugadominated forest, woodlands, thickets, and secondary grassland in Angola, Namibia, Botswana, Zambia, and Zimbabwe (Burgess et al., 2004). These dense woodlands, described in the southeastern parts of Gambos, appear similar to the dense Baikiaea-Burkea woodlands fi rst described for the Okavango basin along the Cubango River, characterised by a closed canopy and thicket-like understorey (Revermann & Finckh, 2013;Wallenfang et al., 2015). Further north of Gambos, Baphia massaiensis subsp. ...
We conducted a vegetation survey in the woodlands of Huíla Province, Angola, with the aim of investigating woodland tree communities and species associations. Vegetation sampling was conducted using vegetation plots of 1 000 m2 where all tree species with or above 5 cm trunk diameter (DBH) were measured. A total of 456 vegetation plots were assessed and a total of 32 080 individual trees measured. Vegetation classification using the ISOPAM algorithm resulted in 13 distinct tree communities. The most dominant family was Fabaceae, subfamily Caesalpinioideae, followed by Combretaceae and Euphorbiaceae. The classification resulted in seven tree communities belonging to the miombo woodlands, two tree communities from Mopane, two from the Baikiaea-Baphia-Terminalia woodlands, and two other distinct tree communities. In general, the miombo communities were the most diverse. The study represents the fi rst plot-based vegetation survey for the region, and will provide the basis for the elaboration of the first vegetation map of Huíla Province.
... The more mesic areas in the north are dominated by miombo woodlands (Figure 1). At the foot slopes of the Angolan Central Plateau, where climate progressively becomes drier, miombo gives way to more open Baikiaea-Burkea woodlands (Stellmes, et al. 2013a;Revermann & Finckh 2013c). Besides woodlands there are various edaphic grasslands in the extreme north, tropical peat bogs on the valley bottoms in the miombo region, growth (United Nations, Department of Economic and Social Affairs 2015), industrialised agricultural schemes, e.g. the 'emerging soybean frontier' (Gasparri et al. 2015), and new 'development corridors' (Laurance et al. 2015), pose enormous challenges for sustainable land management in sub-Saharan Africa. ...
Aim: The social-ecological systems of south east Angola currently undergo rapid transformations and at the same time the region is highly understudied. We aim to provide a first comprehensive analysis of vegetation types, their environmental drivers and woody species diversity of the region. Study area: Cubango River Basin in south-east Angola and northern Namibia. Methods: We conducted a plot-based vegetation survey covering all major terrestrial vegetation types. 190 relevés of 1000 m2 were classified based on a numerical classification approach. We used NMDS ordination and data on soils from field sampling, topography, climate and remotely sensed land surface phenology to investigate vegetation-environment relationships. The number of woody species was estimated using four non-parametric species richness estimators and rarefaction curves. Results: We provided a detailed description of the resulting twelve woody plant communities, in terms of species composition, structure, and habitat characteristics. At the scale of the Cubango Basin, differences in the regional climate were the most important drivers of plant species composition. Topsoil properties did not vary much throughout the study area, but higher contents of silt and clay in the lower soil horizons appeared to drive species composition in the miombo woodlands. Furthermore, we demonstrated how the usage of land surface phenology metrics add value to the interpretation of ecological properties of plant communities in providing insights on the timing of the growing season and on different aspects of above-ground biomass. The number of woody species in the entire Cubango Basin was estimated to be 471 (SD=29) species, for the miombo woodlands 302 (SD=11) species, and for the Baikiaea woodlands 262 (SD=20) species. Conclusion: The presented classification scheme and the analysis of environmental drivers of vegetation types provide a solid basis for future investigations of the vegetation of southeast Angola, and will provide important baseline data for conservation planning and sustainable natural resource management.
... The research area is located in the North-East of Namibia sharing the middle section of the river with Angola ( Mendelsohn 2009). Although a significant proportion of the Okavango basin is still covered with primary forest of different types ( Revermann & Finckh 2013) more than 70 percent of the riverine vegetation has been lost over the last decades ( RoN 2004). The need for agricultural land is the main driver of deforestation ( Proepper et al. 2010). ...
Ecosystems all around the world generate a wide range of provisioning, regulating and cultural services. Often there are trade-offs where optimizing one ecosystem service (ESS) provision reduces other ESS. Managing such trade-offs requires adapted and effective governance. Our work contributes to finding appropriate institutional mechanisms by identifying critical action situations related to the provision and appropriation of ESS. We demonstrate our approach with six forest cases in Asia, Africa and Latin America. Data have been collected by case experts working in different transdisciplinary research projects. Our results confirm that ecosystems are managed in a complex landscape of interacting action situations. There is a tendency that ecosystem management, which provides public goods and common pool resources is under strong pressure to be transformed into one which provides a more narrow range of private goods. Our approach enriches the ESS and SES discourses by detailing and operationalizing the linkage of ESS with human agency and governance and in this way makes the ecosystem service concept more operational for decision makers. It further provides new entry points for social-ecological system analyses.
The final version of this paper can be found under https://www.researchgate.net/publication/326930776_Identifying_governance_challenges_in_ecosystem_services_management_-_Conceptual_considerations_and_comparison_of_global_forest_cases
... The vegetation of the study site is dominated mainly by typical Miombo woodlands species [23]. Brachystegia spp., Julbernardia paniculata, Cryptosepalum exfoliatum subsp. ...
The study was carried out in the Cusseque area of the Municipality of Chitembo in south-central Angola. Our objectives were to assess the floristic diversity, the species composition, and stand structure of Miombo woodlands during regeneration after shifting cultivation. A total of 40 plots of 1000 m 2 were surveyed and analyzed, corresponding to mature forests/woodlands and three fallow types of different age. The analyses were based on plot inventories of all trees with DBH ≥ 5 cm. A total of 51 woody species, 38 genera, and 19 families were recorded. The dominant family was Fabaceae, with subfamily Caesalpinioideae being very abundant. Shannon Diversity and Evenness were highest in mature forests and young fallows, while the mature forest stands showed the highest species richness. A Principal Coordinates Analysis (PCoA) showed many species shared between the intermediate fallow types, but only few species were shared with young fallows. Mature forests formed a clearly distinct group. This study shows potential pathways of forest recovery in terms of faster regeneration after agricultural abandonment and, thus, the results presented here can be used in future conservation and management plans in order to reduce the pressure on mature forests.
... As climate becomes drier, the closed Miombo woodlands give way to the more open Baikiaea-Burkea woodlands of the middle reaches. The area surrounding the delta to the east is dominated by Colophospermum mopane woodlands, while the driest areas to the west and south of the delta are covered by thornbush savannas formed by various Acacia communities [38]. [39] and the location of vegetation plots used in this study. ...
... Quantitative information on the vegetation, especially on the large Angolan share of the Okavango Basin, is scarce and limited to descriptive studies from the pre-independence era, i.e., before 1975 [41][42][43][44]. During The Future Okavango (TFO) project, we initiated an extensive plot-based vegetation survey based on a random stratified sampling design to ensure coverage of all major vegetation types of the basin (GIVD database ID: AF-00-009) [37,38,[45][46][47]. However, the remoteness, limited access and the danger of land mines posed restrictions on the sampling. ...
In many parts of Africa, spatially-explicit information on plant α-diversity, i.e., the number of species in a given area, is missing as baseline information for spatial planning. We present an approach on how to combine vegetation-plot databases and remotely-sensed land surface phenology (LSP) metrics to predict plant α-diversity on a regional scale. We gathered data on plant α-diversity, measured as species density, from 999 vegetation plots sized 20 m × 50 m covering all major vegetation units of the Okavango basin in the countries of Angola, Namibia and Botswana. As predictor variables, we used MODIS LSP metrics averaged over 12 years (250-m spatial resolution) and three topographic attributes calculated from the SRTM digital elevation model. Furthermore, we tested whether additional climatic data could improve predictions. We tested three predictor subsets: (1) remote sensing variables; (2) climatic variables; and (3) all variables combined. We used two statistical modeling approaches, random forests and boosted regression trees, to predict vascular plant α-diversity. The resulting maps showed that the Miombo woodlands of the Angolan Central Plateau featured the highest diversity, and the lowest values were predicted for the thornbush savanna in the Okavango Delta area. Models built on the entire dataset exhibited the best performance followed by climate-only models and remote sensing-only models. However, models including climate data showed artifacts. In spite of lower model performance, models based only on LSP metrics produced the most realistic maps. Furthermore, they revealed local differences in plant diversity of the landscape mosaic that were blurred by homogenous belts as predicted by climate-based models. This study pinpoints the high potential of LSP metrics used in conjunction with biodiversity data derived from vegetation-plot databases to produce spatial information on a regional scale that is urgently needed for basic natural resource management applications.
... The basin has a north-south gradient from semi-humid to semiarid conditions (Weber 2013c). It covers a system of different types of woodland savannas, floodplains and extended wetlands (Revermann & Finckh, 2013). ...
The Okavango Basin is undergoing a process of rapid transformation. The land which contributes essentially to rural livelihoods is under pressure due to population growth, climate change and resulting degradation. Future sustainable land use and cooperation in land management depends on the design of institutions, social norms and the overall legal framework.
The land in the Okavango Basin is under communal management where traditional leaders play important roles in land allocation and access to its resources. There is an ongoing debate on traditional authorities and customary law in African societies. Legal pluralism strongly characterizes various models of land governance in these countries. This discussion is very prominent in Namibia and Botswana, two countries with significantly different policies over the last decades with regard to traditional authorities.
Traditional authorities are often considered as inherently undemocratic, autocratic and backward. In response, different governments introduced policies which control and limit the ability of traditional leaders to administer land on the basis of customary law. The power over land is a key source of their legitimacy and deluding this power weakens their capacity to fulfill fundamental coordinating functions in the communities. Nevertheless, traditional authorities still exert strong influence not only in the daily life of communities but also, in particular, in settling disputes in land and natural resource management. In fact, they still enjoy great acceptances and provide important institutional services. Traditional authorities as a social institution have proven to be resilient and adaptable, persisting during colonialism and continuing to play an important role in the post colonialist era marked by constitutionalism.
Various studies report a strong public acceptance and popularity of traditional leaders. We see two key explanations for this: a) They are culturally accepted because of deeply rooted social norms in society; and b) They provide institutional services – including land administration - in a more affordable and accessible way than local governments. The main objective of this paper is to better understand whether traditional authorities are primarily accepted due to the functions and services which they provide or due to internalized social and cultural norms.
To assess the intrinsic norm dimension of the acceptance of traditional authorities we played an anonymous public good experiment with 213 household heads in rural villages in Botswana and Namibia. In order to approximate as much as possible the real life situation the experiment was framed according to local settings of land and resource use.
To analyze how cooperation behavior in the research communities changes with different authorities, traditional or government enforcing rules, we introduced a rule with a punishment mechanism to the game. The rule in the experiment was labelled for part of the group “customary law”, which is enforced by traditional leaders and for the other part “statutory law”, which is enforced by the government. The introduction of the rule allows us to analyze whether the different labelling of the same tangible incentive affects the compliance with the rule in the cooperation dilemma.
Summarizing the experiment results, we observe notably high cooperation levels with average contributions of 61 percent and 55 percent, respectively, even without any treatment intervention. The introduction of a sanctioned rule considerably increased the average contributions to the public good compared to the baseline and the control group. Average contributions grew up to 93 percent in Botswana and 86 percent in Namibia, while 87 percent and 70 percent of the players complied with the rule of full contribution, respectively.
Our experimental results indicate that the research communities clearly respond to the introduction of rules encouraging cooperation. This should not be taken for granted as numerous studies in different settings revealed that exogenous rules crowd out strong moral and social norms and do not lead to better outcomes. At least in our case, rules can help to form better expectations which can explain partly the increase in cooperation and rule compliance.
At the same time, we do not detect any significant difference in the contributions and compliance between the statutory and customary law treatment. The statutory law and customary law treatment with the same incentive mechanism do not produce any behavioral differences in the experiment. Neither descriptive statistics, nor significance tests and multivariate analyses uncover any variation in the responses.
These findings are supported by responses from our surveys with household heads in the Kavango region of Namibia on rules in land and forest management. The majority of respondents understand that traditional leaders or a combination of both, traditional and state authority, make rules with regard to land and forest use. People accept both governance institutions for various spheres of decision situation. A considerable 91 percent of the respondents trust in state and traditional authorities at the same time. Similarly, the Botswana Afrobarometer in 2014 reports that the majority of respondents also trust both governance institutions, while traditional authorities are more trusted than any other governance organization. With regard to our research question, our findings suggest that traditional authorities are highly trusted and accepted, and that their legitimacy is derived from the function and services they provide.
Looking at differences between subgroups of the sample we observe that in line with widespread arguments women are in Botswana less responsive to traditional compared to statutory authorities. Rather surprising are the results that in both countries, the poorly educated comply less with the customary than to the statutory law. The uneducated are often considered leading a more traditional lifestyle and there is criticism that modern statutory bureaucracies rather than traditional authorities discriminate them. It is also not the most expected result that in Namibia the wealthier more strongly listen to the traditional authorities.
Overall, a considerable majority of players comply with traditional as well as government leaders, irrespective of their label. This indicates that internalized preferences based on social norms for the one or the other organization play no significant role. Our results lead to the conclusion that whenever surveys reveal strong positive attitudes towards traditional authorities such positions are more strongly based on the instrumental value and the performance of traditional leaders. The often negatively presented traditional authority system is at least not less accepted than democratic structures. We do not conclude that statutory law is equally or less effective than customary law in land management. One has to take into account that statutory and customary mechanisms of social regulation and land allocation differ substantially affecting the transaction costs and efficiency of institutions. It has, however, often been stated that traditional authorities are much more accessible to rural African communities than state offices. It can be seen in this context that conflict resolution, in particular related to land disputes, is one of the most popular quoted service traditional leaders provide in rural areas. Considering the complexity to design cost effective and accessible formal government provision structures in rural areas the results have important implications for the overall land governance.
