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There is growing global consensus that assessments of land degradation be conducted at regional or smaller scales. Working at this scale allows for locally relevant environmental and land use conditions to be incorporated into the assessment methodology. In this paper, a recently developed regional approach to assessing land degradation in the Hardeveld bioregion of the Succulent Karoo is applied to the Little Karoo region of this biome. The methodology uses fuzzy classification statistical techniques to combine field data with multiple Sentinel-2A and Landsat vegetation indices, as well as regionally modelled soil variables. The resultant habitat condition archetype map values show strong correlation with field observations of perennial plant and bare soil cover in 96 ground-truthed plots. The archetype map indicates that heavily degraded hotspots of high bare ground cover occur throughout the project region, although there is an overall lower average habitat condition in the western half of the Little Karoo. The mean habitat condition archetype value for the entire project area is 0.54 (standard deviation = 0.13), on a continuous scale where 0 and 1 represent the most degraded and pristine extremes, respectively. Random forest regression analysis of various environmental covariates of degradation indicates a strong relationship between habitat condition and topographic as well as rainfall variables, although the limited accuracy of modelled livestock data may obscure the negative impacts of overgrazing. The 30 m resolution habitat condition archetype map builds upon previous degradation research in the Little Karoo and has the potential to inform future conservation, restoration, and rangeland management decisions. The methodology was successfully transferred to a new region and provides an opportunity to improve reporting on the extent of land degradation across South Africa. • Effective transfer of methodology for regional scale assessment of degradation. • Western Little Karoo has lower habitat condition score than the eastern part. • Topography, rainfall, and land use history influence habitat condition score. • 30 × 30 m habitat condition map can inform sustainable land management decisions. [ABSTRACT FROM AUTHOR]

Abstract MARAS (Monitoring of Arid and Semiarid Regions) consists of 379 ground monitors in Patagonia, a 624.500 km2 semiarid area of southern Argentina and Chile. The objective of this paper was to describe the system and analyze four variables of the initial data base. Floristic composition, diversity and cover were analyzed with intercept lines (500 points). Patches (resource-sinks areas) and Interpatches (areas that loose resources) were described using Gap intercept lines (50 m). Eleven Landscape Functional Analysis indicators were recorded in 10 interpatches: Soil stability, Infiltration and Nutrient cycling. Vegetation Cover was 43 ± 2%, Richness 15 ± 7 species/monitor, Interpatch Size 154 ± 134 cm and LFA Stability Index 46 ± 1%. Cover, Richness and Stability maps had bimodal distribution and maximum in S and NE areas, following rainfall gradients. Variability analysis shows that cover estimations are within 5% error at site and regional scales. Graphical analysis of single monitors shows observational biases in interpatch size and LFA Stability index. Richness estimations correlate significantly with α diversity (R2 = 0.80). Analysis of 5-year change in 115 monitors shows significant reductions in cover and interpatch length, especially N of the region. These base line evaluations enable analysis of future changes that were not possible with multiple techniques and isolated data bases. Highlights • 379 ground monitors of vegetation and soil were installed in Patagonia. • Six teams in two countries shared a single protocol and data base. • Errors of estimations at site and regional scales are acceptable. • Contour maps of main variables show gradients associated to aridity. • This baseline enables future change evaluation. [ABSTRACT FROM AUTHOR]

Abstract The large and widespread decline of European migratory birds spending the northern winter in the Sahel suggests – on top of adverse changes in the breeding quarters ‒ pivotal changes in African overwintering areas. This paper attempts to answer three questions related to the sub-Saharan region: (1) can a change in the woody vegetation explain the decline of migratory birds feeding in trees, (2) ditto for the ground vegetation and bird species searching for food on the ground, and (3) are African bird species also in decline? The analysis is confined to the western Sahel (annual rainfall 100–400 mm, 15.5–18°N and 14.7–16°W), a region intensively used as rangeland but too dry for agriculture. The woody cover, largely stable before 1970, declined in the driest zone by 90% between the 1960s and 2000s, and by 40% in the more humid zone where the woody cover was already low in the 1960s. The woody vegetation changed in many places from an Acacia savanna into an open savanna with scattered bushes and few trees, concomitant with a shift in species composition. These changes took place during a prolonged drought (1969–1992), and were aggravated by increased grazing pressure after the construction of boreholes as evident from the loss of woody cover close to boreholes. A comparison of bird composition and densities in grazed and ungrazed areas and in three study sites intermittently surveyed between 1960 and 1994, with our surveys in the same sites in 2014–2015, revealed about 80% losses for birds feeding on the ground. The increased grazing pressure of livestock must have caused a large reduction of the soil seed bank and most likely also of insects. Between 15 and 16°W an estimated 8 million arboreal birds, mainly migrants, and 30 million ground-feeding birds, mainly granivorous residents, lost their habitat. Assuming that this zone is representative for the Sahelian rangelands as a whole, 1.5–2.0 billion birds have lost their habitat in half a century. Highlights • Sahelian savanna has changed due to the increased grazing pressure by livestock. • Woody cover declined by > 80% during the dry 1980s and 1990s. • Loss of woody cover affected migratory birds, especially those from S. Europe. • Granivorous birds, mostly residents, declined by c. 80%. [ABSTRACT FROM AUTHOR]

Many scholars of rangeland institutions have found fertile theoretical and empirical ground in early efforts by the Kenyan government and international development agencies to socially engineer a shift from open range to discrete territories held under collective freehold title. A rich literature on the dynamics of subsequent subdivision of these “Group Ranches” elucidates a complex interplay of exogenous and endogenous drivers. This paper, on the contrary, explores the dynamic tensions between individualization and collectivization of land and related benefit flows in a group ranch that has thus far not undergone formal subdivision. Research was conducted in Koija Group Ranch, one of 13 group ranches located in Mukogodo Division, on the Laikipia plateau. Drawing on key informant interviews and focus group discussions with those differentially positioned relative to the benefits of de facto processes of rangeland exclosure, and household surveys to document trends in participation and perception, we explore how these processes are perceived and governed. Cross-case comparison highlights the suite of factors shaping which forms of enclosure are contested; the diversity of legitimizing tactics that ensue from such contestation; and the balancing act these tactics represent between retention of privilege and restoration of peaceful relations among group ranch members. [ABSTRACT FROM AUTHOR]

Abstract: The impacts of grazing pressure and rainfall variability on rangeland dynamics have been the topic of much debate. Understanding the combined impact of these two factors is crucial for the development of efficient management strategies for rangelands. In this paper, the impacts of grazing and rainfall variability on the dynamics of a Sahelian rangeland in Northern Senegal are examined. Specifically, the paper assesses their combined impact on species composition, above-ground phytomass production and rain-use efficiency (RUE), on the basis of a 10-year (1981–1990) grazing experiment conducted in the Widou-Thiengoly catchment in the Ferlo, Northern Senegal. The experiment included both a high (0.15–0.20TLUha−1, corresponding to current grazing) and a medium (0.10TLUha−1) grazing pressure. It is shown that species composition, above-ground phytomass production and RUE markedly differ for these two grazing regimes—and that the differences are most pronounced in years with low rainfall. In dry years, both above-ground phytomass production and RUE are significantly reduced in the plots subject to a high grazing pressure. Consequently, the impacts of high grazing pressures on the productivity of the Ferlo are hardly noticed during years with normal or above normal rainfall, but the rangeland''s productivity is strongly affected during a drought. The findings have important implications for the management of rangelands; they indicate that high grazing pressures may increase the vulnerability of rangeland ecosystems and local people to droughts. [Copyright &y& Elsevier]

The Afar pastoralists that reside in arid and semi-arid regions of Ethiopia have fallen under increasing pressure as rangelands and natural resources are affected by recurrent droughts, overgrazing, erosion processes, alien plant invasion and governmental land policies. This paper investigates the impact of these environmental, institutional and cultural changes on natural resource management strategies, using empirical research undertaken in four villages of western Afar (Ethiopia) to assess the related challenges to local livelihoods. Qualitative interviews with various stakeholders reveal that the authority and use of traditional common property regimes have been considerably diminished and traditional livelihood practices threatened. Many pastoralists have adopted agriculture in a move away from pure pastoralism to agro-pastoralism, a transition exaggerated by changing property rights and the Federal Government's sedentarisation program, which is presented as a means of reducing poverty. On-going land privatisation and an increased government presence in the region weaken indigenous institutions and cultural practices, with no clear local understanding of the impact on future generations and Afar identity. [ABSTRACT FROM AUTHOR]

Land degradation is extensive, covering approximately 23% of the globe's terrestrial area, increasing at an annual rate of 5–10 million ha, and affecting about 1.5 billion people globally. Such detrimental processes call for urgent and comprehensive action to halt land degradation. In this paper, we assess the causes and extent of land degradation around the world, followed by an outline of the various challenges in implementing a global Zero Net Land Degradation (ZNLD) policy. The concept of ZNLD proposes a scheme under which the extent of global degraded lands will decrease or at least, remain stable. To enable this type of scenario, the rate of global land degradation should not exceed that of land restoration. Restoration efforts should include not only croplands, rangelands, and woodlands, but also natural and semi-natural lands that do not generate direct economic revenues. The United Nations Convention to Combat Desertification (UNCCD) envisages achieving this target by 2030. Despite being seemingly ambitious, the target of ZNLD could be achieved if degraded lands are restored to a considerable extent and, at the same time, land-degrading management practices are replaced with ones that conserve soils. To enable effective implementation of these steps, it is necessary to formulate a ZNLD Protocol aimed at managing assessment actions and maintaining of supportive policies and regulations. Restoration projects could be financed through payments for improving ecosystem services, as well as other economic mechanisms. Achieving the target of land degradation neutrality would decrease the environmental footprint of agriculture, while supporting food security and sustaining human wellbeing. [ABSTRACT FROM AUTHOR]

Abstract: Degradation in arid rangelands is an on-going concern, as they appear to be trapped in a vicious circle of desertification–marginalization–impoverishment. Recent theoretical developments in dryland research strive to provide keys to understanding linked social-ecological systems and land management. One approach, the desert-syndrome, depicts the socio-ecological evolution of drylands as being determined mainly by ecological factors. A second approach, the adaptive management paradigm, acknowledges the existence of socio-ecological systems in drylands which are considered to have adapted to a given political–economic context and a given range of economic and ecological variability. This paper proposes a conceptual framework integrating both approaches in order to point out supplementary important drivers of the socio-ecological evolution of drylands systems, especially rangelands at the global economic and political scale. The analysis is broadly conducted from a political ecology and co-evolutionary perspectives and discusses three main factors: (1) world-wide application of western-based paradigms in resource management and their effect on rangelands, (2) the fossil-fuel based Green Revolution, and (3) capitalist institutions used to regulate agricultural trade and the corresponding tools and policies. The marginalization of arid rangelands is avoidable, but requires real changes in the current general political and economic rationale under which resources are allocated. [Copyright &y& Elsevier]

Accounts of land degradation and desertification in Namibian communal rangelands have seldom illustrated the broader historical context and structural frameworks within which these social-ecological processes have emerged. This paper aims to address this gap, and argues that it is necessary to take into account past state interventions and policies so as to thoroughly understand the drivers of land degradation problems in these parts of the country. Taking the case of Herero pastoralism as an example, the paper shows how a pre-colonial pastoral system keeping overgrazing at bay, but was radically transformed by the colonial state, and illustrates how current land degradation problems in the former Herero 'homelands' are intrinsically linked to past colonial interventions and policies. The analysis shows, however, that despite the calamities of colonialism and its legacies, key rangeland management practices of Herero pastoralism have not entirely disappeared, thus maintaining livestock rearing in the region as a viable way of life. [ABSTRACT FROM AUTHOR]

Abstract: Pasture user groups have become an important tool by which development agencies have sought to improve rangeland condition and resolve inter-herder conflict. However the ability of these groups to improve rangeland condition in the Gobi Desert is rarely examined. In this paper, three and twelve year old pasture user group areas were compared with non-group areas. Herders and local officials in both group and non-group areas were interviewed to compare activities and institutions that may contribute to degradation through overgrazing. Soil and vegetation based indicators of rangeland condition were also assessed. There were some differences in indicators of rangeland condition between pasture user group and non-group areas, but little evidence of institutions or activities specific to the group that could explain this difference. Herders did not seek to manage grazing pressures for natural resource management aims, nor did they enforce or sanction the external spatial boundaries of pasture user groups. These results suggest that the ability of pasture user group to improve rangeland condition in the Mongolian Gobi Desert may have been overstated. [Copyright &y& Elsevier]

Abstract: Many of the complex issues worldwide regarding environmental management and sustainable develo-pment require integrating the social and natural sciences. Nevertheless, while theoretical discussions have been increasingly developed, operative issues are still major barriers to integrated social–ecological analysis. The aim of this paper was to assess regional forage production in semi-arid rangelands as a key feature in social-ecological analysis, by using human organizational units (i.e. counties). We used these state-administrative units to explore demographic and farming indicators in order to address socio-productive implications of different regional forage production dynamics. We studied the forage spatial and temporal dynamics in two different large ecological regions: Monte and Patagonia, under a single administrative unit (i.e. province). Since forage production estimations in arid rangelands are not trivial, we tested two different methods. We found that inter-annual variability in forage production explained the main differences between regions. At a regional level, zones with higher temporal variability in forage production registered less rural residents and farm numbers, but inverse situations were registered at sub-regional scales. We found a non-linear relationship between forage production variability and rural population density. We proposed differentiated policy recommendations regarding rangeland management and animal husbandry, considering both the social and ecological contexts. [Copyright &y& Elsevier]

Abstract: Although numerous factors influence soil-water content, it is considered a key indicator of rangeland health. This paper investigates the effect of grazing on soil-water content using three treatments within the same soil association. The treatments, simulated holistic planned grazing (SHPG), rest-rotation (RESTROT), and total rest (TREST) applied stocking rates of 36, 6, and 0 animal days/hectare respectively. Soil-water content was measured continuously from 2006 to 2008 using 36 capacitance sensors. Statistical analyses revealed differences in percent volumetric-water content (%VWC) and in all treatments, the SHPG pasture had the highest %VWC. Mixed procedures models indicate strong environmental and treatment effects as explanatory variables for the observed difference in %VWC. Although results of vegetation cover analyses indicated no difference in percent shrub cover in the two production pastures (SHPG and RESTROT), percent litter cover differed in the latter years of this study. It was concluded that in addition to a variety of other factors, management decisions (grazing and rest) can have substantial influence upon soil-water content and that soil-water content can vary substantially as a result of animal impact and the duration of grazing. [Copyright &y& Elsevier]

Abstract: This paper describes a manual-style Decision Support System that integrates land degradation indicators with adaptive management options and is designed for land managers to easily collect data and monitor progress towards environmental sustainability goals. A number of similar tools have been developed for ranchers in southern Africa, but there has been little help for land managers under common property regimes. Manuals were therefore primarily designed for use by communal pastoralists in three study areas in the Kalahari, Botswana. Separate manuals were developed for each study area in response to the differences in indicators and management options deemed relevant for each by local communities. The design of the DSS has been optimised using an “innovation-decision” approach combined with local and external expert review to enhance the likelihood of widespread uptake and application by land managers. Manuals are designed for regular use by pastoralists to identify detrimental environmental change early, and guide sustainable management responses. The recommended assessment procedure is flexible, and designed to make recording and interpretation of results simple for users. Full copies of each manual (in English) are provided (electronic version only). [Copyright &y& Elsevier]

Abstract: There is a growing requirement for techniques to assess land susceptibility to wind erosion, i.e. land erodibility, over large geographic areas (>104 km2). This requirement stems from a lack of wind erosion research between the field (101 km2) and regional scales, and a need to evaluate the performance of spatially explicit wind erosion models across these scales. This paper addresses this issue by presenting a methodology for monitoring land erodibility at the landscape scale (103 km2). First, we define criteria suitable for evaluating land erodibility based on empirical relationships between soil texture, vegetation cover, geomorphology, and wind erosion. The criteria were used to visually assess land erodibility over long distances (103 km) using vehicle-based transects run through the rangelands of western Queensland, Australia. Application of the data for testing the performance of a spatially explicit land erodibility model (AUSLEM) is then demonstrated by comparing the visual assessments of land erodibility with the model output. The model performed best in the west of the study area in the open rangelands. In regions with higher woody shrub and tree cover the model performance decreases. This highlights the need for research to better parameterise controls on erodibility in semi-arid landscapes consisting of forested and rangeland mosaics. [Copyright &y& Elsevier]

Abstract: Semi-arid areas are often considered to be environmentally and economically marginal, a situation which has been exacerbated by economic change, shifts in agricultural production and land use, and changing state policy. These themes are explored with reference to a semi-arid landscape, namely the Karoo, which covers some 40% of the geographic space of South Africa and is used primarily for extensive livestock farming. Despite long-term decline in agricultural output, the traditional mainstay of the region, and weakening small town economies, the Karoo''s population and the economies of its largest service centres are growing. There are, real socio-economic needs and development backlogs, and the situation has been exacerbated by recent political marginalisation. In this study, the small towns of the region are focal points of investigation and provide a lens to investigate the changing demographic and economic dynamics of the Karoo. Most of the region''s population lives in these centres which are service, collection, and distribution points for what traditionally has been an agriculture-based regional economy. This paper explores the concept of marginalisation with specific reference to historical, economic, and demographic change. [Copyright &y& Elsevier]

Abstract: Science is frequently touted as the solution to dryland management problems, yet most management decisions are, by necessity, based primarily on expert knowledge and experience. This paper describes an integrated framework for organizing, synthesizing, and applying our growing understanding of aridland ecosystems using a flexible, multi-objective assessment, monitoring, and management approach. The framework is dual-purpose: (1) to coordinate the use of existing tools, resources, and diffuse knowledge, and (2) to facilitate the integration and application of new knowledge as it is developed. In particular, this framework must facilitate the integration of new knowledge about linkages among landscape units across scales. The framework includes five elements: (1) an ecological site-based approach for categorizing land based on soils and climate, (2) a repository for organizing existing data and knowledge about each ecological site, (3) conceptual models that organize information on the impacts of management and climate variability, and protocols for (4) assessing and (5) monitoring key ecosystem attributes fundamental to a variety of management objectives. Within this framework, basic and applied research are explicitly linked to management of arid and semi-arid ecosystems to more effectively articulate research questions and set research priorities. [Copyright &y& Elsevier]

Abstract: A simple theory of ‘desertification’ is found inadequate for understanding the complexity, diverse patterns and flexibility of farmers’ responses to change in environmental conditions and population growth in the Sahel. These include long-term transitions in farming practices, in management of natural resources and in income diversification. This paper reviews evidence relating to deforestation, woodland and rangeland degradation to show that in certain areas, a transition to intensified land use, although initially involving a loss of woodland, has led to the planting or protection of useful trees on farms and maintained biomass levels. Livestock numbers have been maintained, despite declining rainfall and loss or apparent degradation of rangeland, by development of more integrated livestock, arable and marketing systems. The possibility of these trends having impact on Sahelian ‘greening’ is discussed. [Copyright &y& Elsevier]

Botswana''s Kalahari rangelands have historically supported a diversity of wildlife and a number of subsistence livelihood activities, such as agropastoralism, hunting and gathering. Recently, however, concerns about environmental and livelihood sustainability in the Kalahari have been raised. This paper demonstrates the validity of these concerns using data from research undertaken in the Matsheng area of southwest Botswana. It is illustrated that: (a) Matsheng soils are too infertile to sustain productive arable farming, (b) herbaceous vegetation cover decreases in a reversed decay function towards settlements, (c) the herbaceous vegetation cover trend is inversely reflected by woody-thorny vegetation, (d) despite being a major rangeland activity, livestock production benefits only a minority of inhabitants, and (e) rangelands are no longer the major source of livelihood for the majority. [Copyright &y& Elsevier]