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Rasch, S., et al., (2017), Multi-scale resilience of a communal rangeland system in South Africa, Ecological Economics, 131: 129-138

Resilience has either been assessed on system or individual scale so far. Ignoring the other scale may potentially change the interpretation of resilience in socio-ecological systems (SES). Thus, this paper argues that the co-evolution of both resiliencies must be studied to capture multi-scale complexity. We attempt to close this gap by assessing resilience at both scales of a village community in Thaba Nchu, South Africa. Villagers use a commonly managed rangeland for beef cattle production. An agent based model of household interaction coupled with a biophysical model of the rangeland measures the resiliencies of the SES towards a shock, a stress and a policy intervention. Currently, the SES remains in a stable attractor in terms of SES resilience. Household resilience, however, degrades in a process of structural change. A drought scenario shows improved SES resilience but structural change at household level accelerated. An increase in the number absentee herders increases the likelihood for SES collapse by eroding social embededdness. Finally, an introduced basic income grant demonstrates that the SES is able to cope with an increased number of appropriators. However, interaction of the policy intervention with an exogenous stress translates into an increased probability of SES decoupling.

Oomen, R.J., et al., (2016b). Effect of management on rangeland phytomass, cover and condition in two biomes in South Africa. African Journal of Range & Forage Science 33 (3): 185-198.

In rangelands, grazing management is a main driver of rangeland condition. Due to masking effects of seasonal climate fluctuations, little is known about (dis)similarity of management effects on rangeland condition and forage provision across major dryland biomes. Taking a macro-ecological perspective, we analysed if management effects differed  between  South  Africa’s  central  grassland  and  Kalahari  savanna  biomes.  We  recorded  proxies  of  forage provision (phytomass, vegetation cover and their ratio) over five seasons, annual rainfall to account for seasonal climate  fluctuations,  and  rangeland  condition  (through  relative  abundances  of  increaser  and  decreaser  species).mRegarding  forage  provision,  we  found  effects  of  management  for  the  savanna,  where,  irrespective  of  rainfall, rotational grazing management resulted in higher phytomass and phytomass–cover ratios than management with continuous grazing. In the grassland, however, this difference was only discernible for phytomass–cover ratio in two  years  with  above-average  antecedent  rainfall.  This  suggests  that  management  effects  are  biome-dependent and that modulating effects of annual rainfall are stronger in the grassland. In either biome, management effects on the dominance of increaser and decreaser species were negligible, i.e. rangeland condition did not differ across management  types  in  either  biome.  We  conclude  that  investigations  on  management  effects  should  account  for interactions with biome and rainfall.

Linstädter, A., et al. (2016), Assessing the resilience of a real-world social-ecological system: lessons from a multidisciplinary evaluation of a South African pastoral system, Ecology and Society 21 (3):35

In the past decades, social-ecological systems (SESs) worldwide have undergone dramatic transformations with often detrimental consequences for livelihoods. Although resilience thinking offers promising conceptual frameworks to understand SES transformations, empirical resilience assessments of real-world SESs are still rare because SES complexity requires integrating knowledge, theories, and approaches from different disciplines. Taking up this challenge, we empirically assess the resilience of a South African pastoral SES to drought using various methods from natural and social sciences. In the ecological subsystem, we analyze rangelands’ ability to buffer drought effects on forage provision, using soil and vegetation indicators. In the social subsystem, we assess households’ and communities’ capacities to mitigate drought effects, applying agronomic and institutional indicators and benchmarking against practices and institutions in traditional pastoral SESs. Our results indicate that a decoupling of livelihoods from livestock-generated income was initiated by government interventions in the 1930s. In the post-apartheid phase, minimum-input strategies of herd management were adopted, leading to a recovery of rangeland vegetation due to unintentionally reduced stocking densities. Because current livelihood security is mainly based on external monetary resources (pensions, child grants, and disability grants), household resilience to drought is higher than in historical phases. Our study is one of the first to use a truly multidisciplinary resilience assessment. Conflicting results from partial assessments underline that measuring narrow indicator sets may impede a deeper understanding of SES transformations. The results also imply that the resilience of contemporary, open SESs cannot be explained by an inward-looking approach because essential connections and drivers at other scales have become relevant in the globalized world. Our study thus has helped to identify pitfalls in empirical resilience assessment and to improve the conceptualization of SES dynamics.

Alvarez, M.,et al. (2016), Recovery and germination of Prosopis juliflora seeds after ingestion by goats and cattle, Arid Land Research and Management 30(5):000-000 (in print)

Prosopis juliflora is a perennial shrub introduced in the 1980s to the Baringo District in central Kenya, where it developed into a strongly invasive species since the late 1990s. This period coincides with a shift from cattle to goats in the predominance of the ruminant herds in the area. We hypothesize that endozoochory by goats contributes to the invasive spread of Prosopis. Feeding trials and germination tests assessed the seed recovery in dung and the germination capacity of recovered seeds comparing pod ingestion by goats and cattle. Additionally we compared germination from intact pod sections containing seeds, seeds manually extracted from the pods and seeds scarified with concentrated sulphuric acid for 5 min. After eight days following ingestion only 7% of the seeds ingested by goats and 15% of those ingested by cattle were recovered. While no germination occurred in intact pod segments, germination dynamics were similar in seeds that had been manually extracted from pods with those recovered after intestinal passage. The velocity of germination based on the time required for a 25% of germination (t25) was fastest with acid scarification (1.4 days), followed by the intestinal passage through goats (7.1 days), and the treatments of manual removal and intestinal passage through cattle (11.8 and 15.1 days, respectively). We conclude that in the absence of a scarification of seeds surviving the intestinal passage, the endozoochorous dispersal appears to facilitate the invasive spread of Prosopis by delivering seeds from the pods, distributing them widely and possibly providing nutrients with the dung for establishment and initial growth.

Willy, K.D. and Kuhn, A., (2016): Technology Adoption Under Variable Weather Conditions — The Case of Rain Water Harvesting in Lake Naivasha Basin, Kenya, Water Economics and Policy, 2(2): online

This paper applies a parametric econometric duration model (log–logistic) to analyze the duration of adoption of rain water harvesting techniques (RWHTs) among smallholder farmers in the Lake Naivasha basin, Kenya. The study utilizes survey data from 307 farm-households who are dependent on rain-fed agriculture in a region where rainfall has historically been relatively variable. In such circumstances, RWHT helps to stabilize water supply and help farmers manage weather-related risks. The current study seeks to identify constraints to the spread of RWHTs by exploring how rainfall variability influences the timing of decisions to adopt RWHTs alongside other farm-household and spatial characteristics. Empirical results indicate that although rainfall variability is a significant determinant of time to adoption of RWHTs, farmers’ sensitivity to rainfall variability have declined over time. Instead, access to informal sources of information has gained importance in adoption of RWHT implying that adoption has become more of an endogenous process of social exchange within communities, and less driven by external natural pressure and persuasion by state agents. Other important factors were: age and education level of household head, domestic water demand, ground water abstraction and the number of previous and expected adopters in the village.


Greiner, C., Mwaka, I., (2016), Agricultural Change at the Margins: Adaptation and Intensification in a Kenyan Dryland, Journal of Eastern African Studies, 10(1): 130-149

Land-use and livelihood patterns among Eastern African pastoralists have undergone dramatic change in recent decades. The dynamics in East Pokot effectively illustrate these changes. We focus on the spread and intensification of honey production and crop cultivation, describing the patterns of adaptation and diffusion and the current techniques of production. These processes must be understood as dynamics of agricultural intensification, and not as forms of diversification, because current transformations in pastoral communities go beyond temporal strategies of risk avoidance. In the case of East Pokot, intensification is related to population growth, albeit not in the linear manner proposed by Boserup. Rather, this relation is mediated by variables that include markets, labour, technology and the micro-conditions of the agro-ecological environment.

 

Kuhn, A., et al., (2016), Simulating the viability of water institutions under volatile rainfall conditions - The case of the lake Naivasha Basin, Environmental Modelling & Software, 75: 373-387

This study views the Lake Naivasha Basin in Kenya's Rift Valley as a hydro-economic system with slowly emerging basin-wide water management institutions. Possible institutions face two interlinked challenges. Firstly, large scale horticultural activities as a core economic activity in the basin require substantial and regular amounts of irrigation water, abstracted from the lake and its aquifer. The lake level and thus irrigation water availability reveal a falling trend over the last two decades, which calls for institutions aimed at restricting further expansion in water use. Secondly, the region is characterized by volatile weather conditions where periods of average and above average rainfall have alternated with prolonged droughts for centuries. That leads to highly volatile water inflows into the lake. The two challenges combined thus call for water management institutions that support sustainable water use in both the short and the long run. This study therefore investigates the effect of water institutions already existing or proposed by local stakeholder organizations on preserving target lake levels against a background of highly volatile water availability which negatively affects the economic viability of institutions. To take the absence of functioning basin-wide coordination mechanisms for water allocation into account, we employ the solution format of Multiple Optimization Problems with Equilibrium Constraints (MOPEC) in our integrated hydro-economic model. Stochastic scenario simulations with the model reveal that compliance to water regulations and thus the viability of water institutions in the Naivasha Basin would require very high penalties which are not likely to be accepted by users.

Rasch, S., et al., (2016a), Cooperation and Collapse in a communual livestock production SES model - a case from South Africa, Environmental Modelling & Software, 75: 402-413

Institutional arrangements are considered necessary for successfully governing the commons. They are furthermore thought to be more effective if they are self-organized instead of being imposed. However, endogenous institutional arrangements, like local norms, are specific to a particular socio-ecological systems (SES). This paper presents a SES model of communal livestock producers in South Africa. Its bio-physical component accounts for the impact of biotic and abiotic factors on livestock population. The social agent based component models individual and socially determined behaviour, the latter being a social norm specific to the case. Model results show that cooperative agents obeying and sanctioning the norm reduces the likelihood of SES collapse in terms of livestock population crashes. However, cooperation among agents only emerges in times of ecological crisis where social reorganization is fostered. The crisis creates the opportunity for initializing a self-enforcing process of mutual cooperation. Model specifications are based on survey data and agents were parameterized according to individual household data. A sensitivity analysis shows that this empirical heterogeneity cannot be reduced without changing model outcomes.

Rasch, S, et al., (2016b), Reorganizing resource use in a communal livestock production socio-ecological system in South Africa, Land Use Policy, 52: 221-231

Livestock production on South Africa’s commons contributes significantly to the livelihoods of communal households, offering status, food, income and savings. Management innovations are generally top-down and informed by commercial practices such as rotational grazing in combination with conservative stocking. Implementations often ignore how the specific socio-ecological context affects outcomes and the impact on equity. Science now acknowledges that rangeland management must be context specific and that a universally agreed-upon recommendation for managing semi-arid rangelands does not exist. We present a socio-ecological simulation model derived from a case study in South Africa and use it to assess the socio-ecological effects of rotational vs. continuous grazing under conservative and opportunistic stocking rates. We find that continuous grazing under conservative stocking rates leads to the most favourable outcomes from the social and the ecological perspectives. However, the past legacy under apartheid and participants’ expectations renders its successful application unlikely because enforceability is not ensured.

Oomen, R., et al., (2016a): Modelling rangeland productivity in response to degradation in a semi-arid climate, Ecological Modelling, 322: 54-70

Modelling rangeland is essential for capturing changes at the large temporal and spatial scales at which these systems respond to climate and institutional changes and increasing population pressure, but rangeland models applicable to data sparse regions are rarely available. We developed and evaluated a novel rangeland model aimed at simulating rangeland at different stages of degradation using limited parameterisation and measurements.

The developed model Linrange is a biophysical simulation model of the aboveground part of a mixed grass sward, combined with sub-models for evapotranspiration, soil water dynamics, and root development. Main processes of the biomass model are growth through a source/sink limited mechanism, reserve storage and remobilisation, basal area dynamics, winter dormancy. The grass sward is simulated based on average species characteristics of the dominating grass community.

We show that a model based on simplified biophysical processes and a single set of parameters for a mixed sward can satisfactorily simulate mixed-species rangeland vegetation. The model also could reproduce year-to-year phytomass dynamics, including for exceptionally wet and dry years. Without calibrating specifically for it, the model was able to reproduce observed water-use efficiency values, indicating a good representation of the relationship between the main limiting factor, water, and productivity. By recalibrating the model using only five parameters associated with degradation, the accuracy of simulated degraded rangeland states was close to that of undegraded rangeland. We therefore consider the Linrange model a good tool for research on rangeland dynamics and degradation resulting from management and climate. We also point to directions of further model improvement, particularly regarding the modelling of parameter changes with degradation states.

Sandhage-Hofmann, A., (2016), Rangeland Management. A review. In: book: Reference Module in Earth Systems and Environmental Sciences, Elsevier 1-27, DOI: 10.1016/B978-0-12-409548-9.10455-5

 Rangelands cover great parts of the world and are home of many people worldwide. They provide a wide variety of ecosystem goods and services requested by humans. This includes livestock forage, wildlife habitat, water, mineral resources, wood products, wildland recreation, open space and natural beauty. The geographic extent and the resources of rangelands make their sustainable use and management very important. Range management focuses therefore on grazing by livestock and related ecosystem goods and services. Many rangelands have been altered by persistent vegetation change, invasive species and soil degradation. Additionally, rangelands are facing social and environmental changes, for example, climate change. Future range management has to address these challenges.

Anderson, D.M., Bollig, M., (2016), Resilience and Collapse: Histories, Ecologies, Conflicts and Identities in the Baringo-Bogoria Basin, Kenya, Journal of Eastern African Studies, 10(1): 1-20

The concept of resilience is now applied across the natural and social sciences to provide a means of examining and understanding adaptation and transformation over a longer time period, in response to environmental, economic, cultural, or political shocks or adverse events. This essay introduces a collection of 10 studies that analyse resilience in the context of the Baringo-Bogoria basin, a predominantly savannah ecological zone in Kenya's northern Rift Valley. Framed by the adaptive cycle model, the studies span a history of 200 years, but also detail current challenges to the social-ecological system of the region. Resilience has allowed the communities of Baringo-Bogoria to adapt and transform in order to maintain production systems dominated by cattle pastoralism, with intensive agriculture in niche locations. The authors suggest that the most recent challenges confronting the peoples of this region – intensified conflicts, mounting poverty driven by demographic pressures, and dramatic ecological changes brought by invasive species – have contributed to a collapse in essential elements of the specialised cattle production system, requiring a re-orientation of the social-ecological system.

Becker, M., et al., (2016), Land-Use Changes and the Invasion Dynamics of Shrubs in Baringo, Journal of Eastern African Studies, 10(1): 111-129

In the semi-arid savannahs around Lake Baringo, Kenya, the recent spread of bush encroachment by the invasive alien species Prosopis juliflora and the native Dodonaea viscosa has changed human–environment interactions. This article suggests how the spread dynamics of Prosopis and Dodonaea have operated. It also describes the strategies Baringo's peoples have adopted in the face of this dramatic bush invasion, relates these dynamics to current invasion theory, and analyses possible implications for Baringo's social–ecological systems. It is suggested that recent increased climate variability has triggered changes in land management and livelihoods around Lake Baringo, paving the way for bush encroachment and species invasion. The extent and speed of these changes has exceeded the capacity of local communities to adapt their productive systems, destabilizing the socio-ecology of the dryland savannahs around Lake Baringo and placing them in imminent danger of collapse.

Bollig, M., (2016), Adaptive Cycles in the Savannah: Pastoral Specialization and Diversification in Northern Kenya, Journal of Eastern African Studies, 10(1): 21-44

Comparative evidence from Eastern Africa suggests the emergence of a highly specialized mobile pastoral livelihood came about in the early- to mid-nineteenth century. Developments in the late twentieth and early twenty-first centuries have seen a distinct turn away from this model of pastoral specialization, towards a more mixed and spatially varied set of livelihood strategies. Low intensity warfare, environmental degradation, rapid population increase, and a shift away from cattle pastoralism and towards goat and camel herding are all evident in the current transition of Pokot livelihoods. Lifestyles have become more sedentary and diversified, while agricultural activities have rapidly spread, with the increased marketing of livestock and other commodities. This article traces the history of these changes among the pastoral Pokot of north-western Kenya (today's Baringo County), using the notions of the adaptive cycle and resilience as key explanatory tools in seeking to understand the patterns and drivers of change over time.

Greiner, C.; Sakdapolrak, P. (2016): Migration, Environment and Inequality: Perspectives of a Political Ecology of Translocal Relations. In: Schade, J., Faist, T.; McLeman, R. (Eds). Environmental Migration and Social Inequality, Springer, Cham, pp. 151-163.

Research into the relationship between environment and migration—particularly how the environment influences the decision to migrate—has gained currency in the last decade. However, the growing body of recent environmental-migration literature exhibits an under-theorized and depoliticized notion of the environment. Furthermore, migration is usually perceived as an emergency response, a one-time movement, neglecting the often inherent circularity and continuous effects of migration. In this chapter, we introduce the concepts of translocality and political ecology as a means to address this lapse. We also propose a political ecology of translocal relations as a framework for research into the migration-environment nexus. This to be an important issue in this time of mounting and often reductionist debates.

Vehrs, H.-P., (2016), Changes in Landscape Vegetation, Forage Plant Composition and Herding Structure in the Pastoralist Livelihoods of East Pokot, Kenya, Journal of Eastern African Studies, 10(1): 88-110

Oral evidence from pastoral Pokot on vegetation changes in the rangelands of northern Baringo District points to major changes in structure and biodiversity composition over the past century. A landscape of perennial grasses has turned into an Acacia-dominated bush-land. Pelil (Acacia nubica), talamogh (Acacia mellifera), or anyua (Acacia reficiens), which characterise the pastoral landscape today, have increased rapidly since the 1950s. This article compares perceptions of current changes in grass compositions with former accounts, highlighting local assessments of declining high-quality grasses such as abrute (Brachiaria deflexa, Setaria homonyma) or puyun (Eragrostis cilianensis). The changes described are linked to a number of causal factors (high grazing pressure, restriction of pastoral mobility, increasing population numbers), allowing us to historicise the profound change in landscape vegetation. The costs and benefits of bush encroachment are also examined. The tremendous increase in goat numbers, and the sizeable growth of camel herds, is closely connected to the increased availability of fodder plants for browsers. The article concludes by contrasting the views expressed on landscape by Pokot elders with scientific accounts of environmental change.

Tewes, A., et al., (2015), Using RapidEye and MODIS Data Fusion to Monitor Vegetation Dynamics in Semi-Arid Rangelands in South Africa, Remote Sensing, 7 (6): 6510-6534

Image time series of high temporal and spatial resolution capture land surface dynamics of heterogeneous landscapes. We applied the ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model) algorithm to multi-spectral images covering two semi-arid heterogeneous rangeland study sites located in South Africa. MODIS 250 m resolution and RapidEye 5 m resolution images were fused to produce synthetic RapidEye images, from June 2011 to July 2012. We evaluated the performance of the algorithm by comparing predicted surface reflectance values to real RapidEye images. Our results show that ESTARFM predictions are accurate, with a coefficient of determination for the red band 0.80 < R2 < 0.92, and for the near-infrared band 0.83 < R2 < 0.93, a mean relative bias between 6% and 12% for the red band and 4% to 9% in the near-infrared band. Heterogeneous vegetation at sub-MODIS resolution is captured adequately: A comparison of NDVI time series derived from RapidEye and ESTARFM data shows that the characteristic phenological dynamics of different vegetation types are reproduced well. We conclude that the ESTARFM algorithm allows us to produce synthetic remote sensing images at high spatial combined with high temporal resolution and so provides valuable information on vegetation dynamics in semi-arid, heterogeneous rangeland landscapes.

Changwony,  K.D., et al.,  (2015),  Feed intake and digestibility by sheep of natural vegetation in the riparian land of lake Naivasha, Kenya, Small Ruminant Research 123:75-82

Riparian lands are key dry season feed resource areas in Kenya. The feed quality of pasturesof Lake Naivasha riparian has previously not been studied. Chronosequence positions cor-responding to 30, 25, 20, and 15 years of land use and four transects perpendicular to thechronosequence representing observed soil differences were selected, intersections form-ing forage sampling plots. A 4 x 4 Graeco-Latin square design experiment using sheep wasconducted to determine voluntary intake, digestibility, and effects of land use duration andsoil type. The sheep were housed in metabolic cages and fed for ad libitum intake. Feedintake and faecal output were recorded and samples taken for analysis. Land use dura-tion did not affect dry matter (DM) and organic matter (OM) intake (DMI and OMI). Thedigestibility of DM and OM and of fibre fractions decreased with increased land use dura-tion. Increased duration of exposure from lake recession and land use leads to increasedforage fibre, reduced digestibility of DM and fibre fractions and reductions in Ca, K and P con-tent but did not affect DM intake. Lake Naivasha riparian pastures would provide sufficientenergy and can, with nitrogen supplementation, be a good feed resource for ruminants. Useof chronosequence approach provides an analytical framework to study effects of land useduration on feed quality

Dold, C. and Becker, M. (2015), Soil attributes and plant production changes in a  tropical littoral Wetland, Journal of Plant Nutrition and Soil Science. 178(4): 609-621

 Lake Naivasha is a freshwater lake in the East African Rift Valley. With continued lake level declines between 1980 and 2011, the newly exposed land areas were gradually taken for agricultural use. The resulting chronosequences allow for an analysis of the effects of land use duration on nutrient dynamics and agricultural production. Transects representing land use durations of 0–30 (cropland) and 15–30 years (pasture) were established on soils formed on alluvial deposits and lacustrine sediments. We assessed changes in topsoil nitrogen (N) stocks (t ha?1), ammonium mineralization potential (N-supplying capacity), and plant-available P with increasing durations of land use. An additional greenhouse experiment studied the responses of kikuyu grass (Cenchrus clandestinus) and maize (Zea mays) in potted topsoil collected from differnt land-use types and chronosequence positions. With increasing duration of land use we noted a significant decline (P < 5%) in soil N contents under both pasture and cropland uses, following a model of exponential decay. The N stocks decreased at 84?kg?ha?1 a?1 and a decay rate constant of 0.019 a?1 in pasture soil within 15 years, and at 75?kg?ha?1 a?1 with a decay rate-constant of 0.013 a?1 in cropland soil within 30 years. While the ammonium-N mineralization potential also decreased with land use duration, the trends were significant only in lacustrine pasture soils. Plant-available P did not show any trends that were related to the duration of land use. Kikuyu grass and maize accumulated less dry matter and N as the duration of use increased. This biomass accumulation was significantly related to soil N. A continued mineralization of soil organic matter has possibly contributed to the observed soil N depletion over time. The continuous agricultural use of the littoral wetland zone of Lake Naivasha is likely to entail declining production potentials for both pastures and food crops.

Sandhage-Hofmann, A., et al., (2015), Rangeland management effects on soil properties in the savanna biome, South Africa: A case study along grazing gradients in communal and commercial farms. Journal of Arid Environments 120: 14-25

Although the savanna biome of South Africa is a major resource for rangeland management, little is known about how differences in rangeland management systems affect soil properties in such biomes. Near to Kuruman, commercial farms have practiced rotational grazing for decades. In communal areas of former homeland Bophuthatswana, similar strategies were used prior to 1994. Nowadays, a continuous grazing system is common. We hypothesized that these changes in management affected soil properties. To test this, we sampled soils at communal and commercial land along a gradient with increasing distance to water points. The results revealed that communal systems with continuous grazing showed enlarged spatial gradients. The soils were depleted in most nutrients close to the water relative to those of commercial systems. In contrast, as the distance to the water increased, the nutrient stocks of these communal systems were higher. Changes in soil nutrient stocks were related to a zone of increased bush encroachment (up to 25%). Specific analyses (phosphorus fractions, particulate organic carbon, ?13C) confirmed that the soils of the communal grazing systems benefited from the shift of grass-dominated to bush-dominated system with woody Acacia vegetation, while the rangeland degraded in the sense that it lost palatable grass species.

Garcia, M., et al., (2014), Response of community-aggregated plant functional traits along grazing gradients: insights from African semi-arid grasslands, Applied Vegetation Science, 17 (3): 470-481

The grassland biome of South Africa is a major resource for livestock farming; yet the soils of these rangelands are stressed differently by various management systems. The aim of this study was to investigate how basic soil properties respond to different management systems. For this purpose we sampled rangeland management systems under communal (continuous grazing), commercial (rotational grazing) and land reform (mixture of grazing systems) farming. Within each of these systems a grazing gradient was identified with decreasing grazing pressure with increasing distance to the water points. Results showed that communal farms with continuous grazing were generally depleted in the respective nutrient stocks. The depletion increased with rising grazing pressure. Along that line there was a breakdown of macroaggregates with losses of the C and N stored therein. However, the commercial farms also exhibited a decline of macroaggregates and their associated C content nearby the water points. Aggregate fractionation is a sensitive indicator for detecting the beginning of soil degradation in this biome; yet, degradation was less pronounced under the rotational grazing of the commercial farms than under communal property right conditions. Hence, soil analyses confirm that fences and appropriate grazing periods are needed to manage these rangelands sustainably.

Linstädter, A., et al., (2014), Are there consistent grazing indicators in drylands? Testing plant functional types of various complexity in South Africa’s grassland and savanna biomes, PLOS ONE, 9, e104672

Despite our growing knowledge on plants’ functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa’s grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs). Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses) and two-trait PFTs (e.g. perennial grasses) performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold) had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may also be useful for identifying ecological indicators in other ecosystems

Brüser, K., et al., (2014), Discrimination and characterization of management systems in semi-arid rangelands of South Africa using RapidEye time series, International Journal of Remote Sensing, 35 (5): 1653-1673

In South African grasslands, rangeland management is strongly related to land tenure. Communal farms are reported to exhibit less desirable vegetation conditions for livestock than commercial farms. Time series of high spatial and temporal resolution imagery may be useful for improved evaluation of these rangelands as they provide information at a spatial scale similar to the typical scale of field assessments and may thus overcome the limited spatio-temporal representativeness of field measurements. A time series of 13 RapidEye images over one growing season (2010–2011) was used to explore spectral differences between and within two management systems (commercial vs. communal). Isomap ordination was applied to map continuous spectral dissimilarities of sample plots. Using regression with simultaneous autoregressive models (SAR), dissimilarities were subsequently related to ecological variables of plant and soil, including indicators for grazing effects. The largest differences were found between sample plots of communal and commercial farms. Vegetation attributes were significantly related to dissimilarities in reflectance, both from the growing season and the dormant period. However, these relationships did not suggest vegetation degradation on communal farms. They further suggest that a management-related pattern of grazing disturbance in the summer months led to spectral differences between farms but could have impaired the detailed characterization of spectral dissimilarities related to differences in vegetation composition.

Lang, B., Sakdapolrak, P., (2014), Belonging and Recognition after the post-election violence: A case study on labour migrants in Naivasha, Kenya, Erdkunkde, 68(3): 185-196

The 2013 general elections in Kenya entailed no recurrence of the 2007–08 post-election violence. Closer examination at the local level, though, indicates that the experiences of violence continue to influence the social sphere. Divisions between a long-established population and newcomers are blatant especially at places with high levels of immigration. This paper addresses how experiences of violent conflict over identitary and territorial belonging affect and transform sociospatial organisation. The analysis is based on an empirical study at one of the venues of the post-election violence, a poor and heterogeneous workers’ settlement in Naivasha in Kenya’s Rift Valley. Naivasha area is internationally known for its horticultural production and massive labour immigration. After the 2007 elections, radical individuals of the local Kikuyu ethnic majority claimed Naivasha as their territory as a reaction to the displacement of Kikuyus from other parts of the country.
Migrants of unwanted ethnic identity or political positioning were murdered or forcibly evicted from the place. Yet, due to poor job opportunities, especially in western Kenya, job seekers continue to migrate to Naivasha. The repercussions of the violence are expressed in the lack of acceptance, on the part of the long-established population at the place, of the presence of labour migrants. Experiences of ethnicised prejudice, mistrust, and fear between the self-described autochthonous population and labour migrants are tenacious. Kikuyus perceive Naivasha as their place of refuge and are willing to defend it if necessary. Migrants barely develop feelings of belonging to Naivasha, seeking rather to enhance their own security during their stay at the place. This study illustrates that memories of the violence still regulate socio-spatial realities and reinforce and accelerate processes of spatial and societal division.

Bollig, M., et al., (2014): Inscribing Identity and Agency on the Landscape: Of Pathways, Places and the Transition of the Public Sphere in East Pokot, Kenya. In: African Studies Review 57(3): 55-78.

Drawing upon the dynamic interrelationship between human agency and space, this article sheds light on the constitution of and relation between “place” and “path” among the pastoral Pokot of East Pokot District in the Kenyan North Rift Valley. It discusses the transformation from a more mobile pastoralist model of spatialization, which relies on a flexible network approach combining paths and places, toward a more “place-making,” postpastoralist model linked to increasing sedentariness, privatization of land, a clearer definition of external and internal boundaries, and a rapid emergence of schools, churches, and other physical structures.

Changwony,  K.D., et al., (2014),  Biomass and quality changes of forages along land use and soil type gradients in the riparian zone of Lake Naivasha, Kenya, Ecological Indicators 49:169–177

 The recession of the water level of Lake Naivasha has incrementally exposed land surfaces creating a chronosequential transect representing durations of 1–30 years of exposure to grazing. This chronosequence provides a unique model to study the effects of land use duration on resource availability and resource base quality. Particularly, pasture quality changes in the riparian land of tropical fresh water lakes have so far not been studied. We assessed the effect of the duration of exposure to grazing on the biomass production, crude protein content and energy quality of pastures in a 4 × 4 latin square design (4 chronosequence positions × 4 soil types). Species composition was recorded and biomass was sampled at monthly intervals from February to August 2011. Soil moisture was recorded using frequency domain reflectometry sensors. Vegetation samples were analyzed for dry matter, nitrogen and metabolizable energy. Increased land use duration favored a shift in species dominance from Pennisetum clandestinum to Cynodon plectostachyus, which was associated with a reduction in dry matter yield and increased plant nitrogen content. All measured variables tended to be higher in soils formed on alluvial than in those formed on lacustrine deposits. Increased soil N and gravimetric moisture content stimulated biomass accumulation. The crude protein yield and metabolizable energy changed with phenological stages of the pasture and declined significantly towards maturity (seed setting of grasses). Continuous grazing and reduced soil moisture content, both during low rainfall and increased distance from the lake shore, affected the composition of pasture grasses as well as forage yield and quality. This may thus differentially affect the suitability of the riparian land as pasture ground and feed resource area for grazing animals.

Naumann, C., (2014), Stability and Transformation in a South African Landscape: Rural Livelihoods, Governmental Interventions and Agro- Economic Change in Thaba Nchu, Journal of Southern African Studies, 40(1): 41-57

Despite an ambitious land reform programme, many rural households in South Africa derive only a small proportion of their livelihoods from agriculture, and tend rather to rely on off-farm incomes, whether in the form of wages from the commercial sector or social grants provided by the government. Focusing on communal areas in Thaba Nchu in the eastern Free State, this article addresses both continuities and transformations of the local land use patterns between the early twentieth century and the current state of low agricultural production. Based on ethnographic, archival, and aerial photographic data, the study retraces critical changes in the social–ecological system, taking into particular consideration the effects of governmental interventions on the agro-economic sector. Although rural Thaba Nchu has undergone profound shifts of land use patterns in its history, agricultural production there was most significantly transformed by the ‘betterment schemes’ initiated by the apartheid government. Initially intended to rehabilitate the reserves, the betterment in fact undermined local agriculture and destroyed rural livelihoods.

Britz, W., et al., (2013), Modeling water allocating institutions based on Multiple Optimization Problems with Equilibrium Constraints, Environmental Modelling & Software, 46 (0), 196-207

Hydro-economic river basin models (HERBM) based on mathematical programming are conventionally formulated as explicit ‘aggregate optimization’ problems with a single, aggregate objective function. Often unintended, this format implicitly assumes that decisions on water allocation are made via central planning or functioning markets such as to maximize social welfare. In the absence of perfect water markets, however, individually optimal decisions by water users will differ from the social optimum. Classical aggregate HERBMs cannot simulate that situation and thus might be unable to describe existing institutions governing access to water and produce biased results for alternative ones. We propose a new solution format for HERBMs, based on Multiple Optimization Problems with Equilibrium Constraints (MOPEC), which allows, inter alia, to express spatial externalities resulting from asymmetric access to water use. This new problem format, as opposed to commonly used linear (LP) or non-linear programming (NLP) approaches, enables the simultaneous simulation of numerous ‘independent optimization’ decisions by multiple water users while maintaining physical interdependences based on water use and flow in the river basin. We show that the alternative problem format allows formulating HERBMs that yield more realistic results when comparing different water management institutions.

Kotze, E., et al., (2013), Rangeland management impacts on the properties of clayey soils along grazing gradients in the semi-arid grassland biome of South Africa, Journal of Arid Enivronments, (97):220-229

The grassland biome of South Africa is a major resource for livestock farming; yet the soils of these rangelands are stressed differently by various management systems. The aim of this study was to investigate how basic soil properties respond to different management systems. For this purpose we sampled rangeland management systems under communal (continuous grazing), commercial (rotational grazing) and land reform (mixture of grazing systems) farming. Within each of these systems a grazing gradient was identified with decreasing grazing pressure with increasing distance to the water points. Results showed that communal farms with continuous grazing were generally depleted in the respective nutrient stocks. The depletion increased with rising grazing pressure. Along that line there was a breakdown of macroaggregates with losses of the C and N stored therein. However, the commercial farms also exhibited a decline of macroaggregates and their associated C content nearby the water points. Aggregate fractionation is a sensitive indicator for detecting the beginning of soil degradation in this biome; yet, degradation was less pronounced under the rotational grazing of the commercial farms than under communal property right conditions. Hence, soil analyses confirm that fences and appropriate grazing periods are needed to manage these rangelands sustainably.

Greiner, C., (2013), Guns, land, and votes: Cattle rustling and the politics of boundary (re)making in Northern Kenya, African Affairs 112 (447): 216-237

Livestock raiding among northern Kenya's pastoralists has changed profoundly in the last decades. Fought with modern weaponry and often extreme violence, raiding is increasingly enmeshed in politicized claims over administrative boundaries, struggles for exclusive access to land, and attempts to establish or safeguard an ethnically homogeneous electoral base. These conflicts are part of Kenya's troubled politics of decentralization and as such they must be viewed in the context of wider political developments in the country. Based on ethnographic fieldwork in East Pokot and surrounding areas in Kenya's Central Rift Valley Province, this article demonstrates how livestock raiding emerges as a specific form of violent regulation, a well-adapted, dangerous, and powerful political weapon.

Greiner, C., Sakadapolrak, P., (2013), Rural-urban migration, agrarian change, and the environment in Kenya: a critical review of the literature, Population and Enivironment, 34 (4): 524-553

The nexus between migration dynamics and environmental change has drawn the attention of many researchers in the recent past. While the majority of studies focus on the impact of the environment on migration decisions, less emphasis has been placed on the feedback effect of migration on the environment in rural sending areas. This article provides a critical review of this relationship by focusing on the rich literature on rural–urban migration of smallholder households in Kenya and its effects on rural environments. The article argues that there are distinct relations between migration, agricultural change and the environment. These are mediated in varying degrees by flows of remittances, loss of labor, socioeconomic stratification, gender dynamics, and cultural factors. Overly generalizing assumptions about these relations, however, fail to grasp their complexity. We propose employing a translocal perspective to enrich future analysis and enhance the understanding of migration–environmental interactions.

Greiner, C., Sakapolrak, P. (2013), Translocality: Concepts, Applications and Emerging Research Perspectives,  Geography Compass 7(5): 373-348

The employment of translocality as a research perspective is currently gaining momentum. A growing number of scholars from different research traditions concerned with the dynamics of mobility, migration and socio-spatial interconnectedness have developed conceptual approaches to the term. They usually build on insights from transnationalism while attempting to overcome some of the limitations of this long-established research perspective. As such, translocality is used to describe socio-spatial dynamics and processes of simultaneity and identity formation that transcend boundaries—including, but also extending beyond, those of nation states. In this review, we trace the emergence of the idea of translocality and summarise the characteristics that different authors associate with the term. We elucidate the underlying notions of mobility and place and sketch out fields of research where the concept has been employed. On the basis of our findings, we conclude by proposing key areas where a translocal approach has the potential to generate fruitful insights

Greiner, C., et al., (2013): From Cattle to Corn: Attributes of Emerging Farming Systems of Former Pastoral Nomads in East Pokot, Kenya. In: Society & Natural Resources 2(12): 1478-1490.

Crop cultivation under rain-fed conditions is a recent innovation among the formerly pastoral-nomadic Pokot in north-central Kenya. We have examined the socioecological dynamics of land-use change from an interdisciplinary perspective. The patterns of transition to agropastoralism are closely related to both the biogeophysical attributes of the area and the economic characteristics of the households. While the use of advanced agronomic practices in the highlands is associated with annual maize grain yields of >2 Mg ha?1, unfavorable climatic and edaphic conditions, as well as the limited agronomic knowledge of the newcomer farmers in the lowland and mid-hill zones, make field crop production there an opportunistic, spatially scattered, and rather erratic land-use strategy. The accelerated transition to crop cultivation and the spatiotemporal differences in sedentarization between zones contribute to a fragmentation and shortage of land, which results in growing interhousehold inequalities and increasing conflicts within Pokot society.

Willy, D.K. and Holm-Müller, K., (2013): Social influence and collective action effects on farm level soil conservation effort in rural Kenya, Ecological Economics, 90: 94-103

This paper analyzes the effects of social influence and participation in collective action initiatives on soil conservation effort among smallholder farmers in Lake Naivasha basin, Kenya. We apply binary and ordered probit models in a two stage regression procedure to cross-sectional data collected through a household survey among randomly selected smallholder farmers. Smallholder farming systems in the research area are associated with practices that render farmlands susceptible to soil erosion causing negative impacts on land and the environment. Therefore, strategies that encourage soil conservation are likely to also offer solutions for dealing with agri-environmental challenges and poverty alleviation. Results indicate that social capital facilitates participation in collective action initiatives which then influence individual soil conservation efforts. Neighborhood social influences, subjective norms, gender, education level, farm size, access to credit and livestock ownership also emerge as key determinants of soil conservation effort. Policy implications drawn by this study encourage strategies to increase participation and effectiveness in collective action initiatives as a boost to soil conservation. Implementation of soil conservation practices could also be encouraged through awareness increasing instruments, facilitating access to agricultural micro-credit and paying attention to gender related challenges on knowledge access and rights over land and other natural resources.

 

Keck, M., Sakadapolrak, P., (2013), What is social resilience?, Erdkunke 67(1): 5-18

Over the last decade, a growing body of literature has emerged which is concerned with the question of what form a promising concept of social resilience might take. In this article we argue that social resilience has the potential to be crafted into a coherent analytic framework that can build on scientific knowledge from the established concept of social vulnerability, and offer a fresh perspective on today’s challenges of global change. Based on a critical review of recently published literature on the issue, we propose to define social resilience as being comprised of three dimensions: 1. Coping capacities –the ability of social actors to cope with and overcome all kinds of adversities; 2. Adaptive capacities – their ability to learn from past experiences and adjust themselves to future challenges in their everyday lives; 3. Transformative capacities – their ability to craft sets of institutions that foster individual welfare and sustainable societal robustness towards future crises. Viewed in this way, the search for ways to build social resilience – especially in the livelihoods of the poor and marginalized – is revealed to be not only a technical, but also a political issue.

Greiner, C., (2012), Unexpected Consequences: Wildlife Conservation and Territorial Conflict in Northern Kenya, Human Ecology, 40 (3):415-425

This article is concerned with the implementation of community-based conservancies (CBC) in conflict-ridden pastoralist areas of northern Kenya and whether the creation of protected areas can facilitate the resolution of conflict. Evidence from ethnographic research in East Pokot, Kenya, reveals a mixed picture. In the last decade, three CBCs were established along the administrative borders. Two of them are located in contested areas between the Pokot and neighboring pastoralists. In order to ensure their long-term success in terms of wildlife conservation and economic viability they must act as catalysts for inter-ethnic conflict resolution. In one case, the implementation proved successful, while in the other it exacerbated tensions and led to ethnic violence. In addition, issues of conservation are also embedded in deeper intra-societal struggles over the reconfiguration and renegotiation of access to and control over land. Drawing on ethnographic data and recent literature this research sheds light on unexpected consequences of CBC.

Naumann, C. and Greiner, C. (accepted): The Translocal Villagers. Mining, Mobility and Stratification in Post-Apartheid South Africa. Forthcoming in: Mobilities.

Internal labour migration from rural areas to urban centres has been and remains one of the dominant patterns of migration in South Africa. Based on data from ethnographic field research, this paper explores the mobility patterns and translocal relations of miners in the Northern Cape province
of South Africa. By considering the tension between mobility and locality in a historical and political perspective, the concept of translocality helps to explain why miners try to expand their action space and, at the same time, why they are embedded in certain places. Thus, a translocal perspective enhances the interpretation of the spatio-temporal transformations in South Africa’s mining communities and beyond, as it sheds light on the agency of mine workers, superseding merely  
tructuralist explanations.

 

 

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