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Background and Aims: The Terminalia cloud forest is endemic to a 200 km stretch of coastal mountains in southern Arabia. This research aims to describe patterns of variation in the species composition of the Terminalia forest in Dhofar, Oman and examine causal environmental factors. Study area: The Jabal Qamar mountain range, Dhofar, Oman. Methods: Hierarchical cluster analysis and indicator species analysis were used to identify and describe variants of the Terminalia forest. Topoclimatic factors, vegetation characteristics and disturbance factors were compared between the variants using ordination and ANOVA or Kruskal-Wallis tests. Results: Six new variants of the Terminalia forest are described. These are the Dodonaea viscosa subsp. angustifolia shrubland variant, Cadia purpurea-Olea europaea forest variant, Euclea racemosa-Jasminum grandiflorum shrubland variant, Gymnosporia dhofarensis-Ficus sycomorus woodland variant, Jatropha dhofarica-Zygocarpum dhofarense sparse woodland variant and the Premna resinosa-Hybanthus durus forest variant. A seventh variant was identified, which was previously described by Kürschner et al. (2004); the broad-leaved Blepharispermum hirtum shrubland. The species composition and environmental conditions indicate that two variants are the result of anthropogenic disturbance, whilst the other variants are well separated along fog density and topographic position gradients. Conclusions: Distinct variants of the Terminalia forest in Jabal Qamar result from spatial variability in environmental conditions associated with the complex topography, monsoon fog distributions, and anthropogenic disturbance. The results of this study could assist practitioners to rapidly identify and prioritise these variants for conservation. [ABSTRACT FROM AUTHOR]

In the central South Arabian mountains of Yemen and Oman, monsoon fog interception by the endemic cloud forest is essential for ecosystem functions and services. Yet, we know little about the local factors affecting fog distributions and their cumulative effects on vegetation. To examine these relationships, we developed a novel method of high‐resolution fog detection using Landsat data, and validated the results using occurrence records of eight moisture‐sensitive plant species. Regression tree analysis was then used to examine the topographic factors influencing fog distributions and the topoclimatic factors influencing satellite‐derived vegetation greenness. We find that the interplay between the complex mountain topography and the incoming fog results in heterogeneous fog densities. Specifically, fog accumulates against steep windward slopes and landforms, resulting in hotspots of fog interception, while lower fog densities occur in leeward locations. We also find that fog distributions correlate with patterns of vegetation greenness, and overall, that greenness increases with fog density. The layer of fog density describes patterns of vegetation greenness more accurately than topographic variables alone, and thus, we propose that regional vegetation patterns more closely follow a fog gradient, than an altitudinal gradient as previously supposed. The layer of fog density will enable an improved understanding of how species and communities, many of which are endemic, range‐restricted and in decline, respond to local variability in topoclimatic conditions. [ABSTRACT FROM AUTHOR]

Questions: It is frequently reported that overstocking of camels, cattle and goats is degrading the Anogeissus cloud forest, which is endemic to a 200‐km stretch of coastal mountains in southern Arabia. However, livestock impacts on the vegetation have not been assessed. Furthermore, we have a limited understanding of the impacts of large‐bodied browsing livestock, such as camels, in woodland and forest rangelands. Therefore, in this study, we examine the effects of livestock browsing on the species composition, density, and phytomorphology of woody vegetation in the Anogeissus cloud forests in the Dhofar Mountains of Oman. Location: Data were collected at 30 sites in the Jabal Qamar mountain range in western Dhofar, Oman. Methods: The point‐centred quarter method was used to sample the composition, density and structure of woody vegetation. Constrained correspondence analysis was used to quantify the effects of livestock browsing on woody plant species composition, whilst effects on plant density were analysed using mixed‐effects models. Standardised major axis regression was used to examine differences in height–diameter allometry (stunting) under different stocking rates. Results: Fog density, topographic position and long‐term stocking rates were found to be important factors affecting woody species composition. We found lower species diversity and plant density, and higher frequencies of unpalatable species, under higher stocking rates. Juveniles showed a stronger response to stocking rates than adults, and several common species exhibited stunted morphology under high stocking rates. Conclusions: Browsing by large‐bodied livestock, such as camels and cattle, can substantially alter the species composition, structure, and phytomorphology of woody vegetation in semi‐arid woodlands and forests. Juveniles are particularly susceptible to browsing which alters woody vegetation demography and inhibits regeneration potential. Our results support previous suggestions of overstocking in Dhofar and highlight the importance of swift measures to reduce livestock browsing pressure in the Anogeissus cloud forests. [ABSTRACT FROM AUTHOR]

In the Dhofar Mountains of Oman stakeholders are concerned about the social and ecological sustainability of pastoralism. In this study we used interviews with pastoralists to examine the prevailing drivers of pastoralism and how they are changing. We find that people are committed to pastoralism for sociocultural reasons but also that this commitment is under pressure because of husbandry costs and changing values. We find that capital investment in feedstuff enables pastoralists to overcome the density-dependent regulation of livestock populations. However, high production costs deter investment in marketing and commercialization, and there is little off take of local livestock. Our study reveals how pastoral values, passed down within households, motivate pastoralists in the face of high husbandry costs, modernization and social change. [ABSTRACT FROM AUTHOR]