Matter fluxes in mountain oases of Al Jabal Al Akhdar, Oman

Since 1970 when Sultan Qaboos bin Said Al Said took over power from this father, agriculture in Oman has undergone major transformations as a consequence of rapid population and economic growth. In this process groundwater extraction has dramatically increased to meet domestic and agricultural needs. Recently, the agro-ecosystem of ancient mountain oases of Oman have received greater attention as interest has grown to understand the causes of their often millennia old sustainable productivity. Particularly little is known about the carbon (C) and nutrient turnover in these intensive landuse systems. This is partly due to the difficulties to measure such processes in the often remote fields. To fill the existing gap of knowledge, field studies were conducted in five oases at different altitudes of Al Jabal Al Akhdar, the highest agricultural area in Oman, to determine C and nutrient fluxes as well as nutrient use efficiencies for two different cropping systems as affected by temperature, irrigation, and manure quality. The results of this study indicated that water scarcity as a result of low precipitation and an increase in urban water consumption is a major threat to the sustainability of agriculture in these oases. Optimizing the use of irrigation water is a major challenge for agriculture in these oases, particularly given ever increasing competition for this most limiting resource. Traditionally, farmers of these oases adapt to variation of irrigation water supply by minimizing the growing area of annual crops, leaving these areas uncultivated through drought seasons (Luedeling and Buerkert 2008). In this study, a remarkable reduction in annual crop area was observed in 2009 for all oases. Our results suggested that water scarcity as a result of low precipitation and the increase in urban water consumption cause such changes in land use. The data also underline the intensive C and nutrient turnover in the man-made irrigated agroecosystems and confirmed the importance of the large manure quantities applied continuously to the terraces as a key factor responsible for sustainable soil productivity. To trace the fate of C and plant nutrients that are released from the large amount of manure applied by oasis farmers, more detailed studies under controlled conditions, using isotope signatures, would be needed.

Effects of changing water availability on land use in irrigated mountain oases of Al Jabal Al Akhdar, northern Oman

In Oman, during the last three decades, agricultural water use and groundwater extraction has dramatically increased to meet the needs of a rapidly growing population and major changes in lifestyle. This has triggered agricultural land-use changes which have been poorly investigated. In view of this our study aimed at analysing patterns of shortterm land-use changes (2007-2009) in the five irrigated mountain oases of Ash Sharayjah, Al’Ayn, Al’Aqr, Qasha’ and Masayrat ar Ruwajah situated in the northern Oman Hajar mountains of Al Jabal Al Akhdar where competitive uses of irrigation water are particularly apparent. Comprehensive GIS-based field surveys were conducted over three years to record changes in terrace use in these five oases where farmers have traditionally adapted to rain-derived variations of irrigation water supply, e.g. by leaving agricultural terraces of annual crops uncultivated in drought years. Results show that the area occupied with field crops decreased in the dry years of 2008 and 2009 for all oases. In Ash Sharayjah, terrace areas grown with field crops declined from 4.7 ha (32.4 % of total terrace area) in 2007 to 3.1 ha (21.6 %) in 2008 and 3.0 ha (20.5 %) in 2009. Similarly, the area proportion of field crops shrunk in Al’Ayn, Qasha’ and Masayrat from 35.2, 36.3 and 49.6 % in 2007 to 19.8, 8.5 and 41.3 % in 2009, respectively. In Al’Aqr, the area of field crops slightly increased from 0.3 ha (17.0 %) in 2007 to 0.7 (39.1 %) in 2008, and decreased to 0.5 ha (28.8 %) in 2009. During the same period annual dry matter yields of the cash crop garlic in Ash Sharayjah increased from 16.3 t ha-1 in 2007 to 19.8 t ha-1 in 2008 and 18.3 t ha-1 in 2009, while the same crop yielded only 0.4, 1.6 and 1.1 t ha-1 in Masayrat. In 2009, the total estimated agricultural area of the new town of Sayh Qatanah above the five oases was around 13.5 ha. Our results suggest that scarcity of irrigation water as a result of low precipitation and increased irrigation and home water consumption in the new urban settlements above the five oases have led to major shifts in the land-use pattern and increasingly threaten the centuries-long tradition and drought-resilience of agriculture in the oases of the studied watershed.

Sustainability of Small Scale Farming in a Mountain Region: Case Study of the Khaling Rai Population of the Solukhumbu, Nepal

The Khaling Rai live in a remote area of the mountain region of Nepal. Subsistence farming is central to their livelihood strategy, the sustainability of which was examined in this study. The sustainable livelihood approach was identified as a suitable theoretical framework to analyse the assets of the Khaling Rai. A baseline study was conducted using indicators to assess the outcome of the livelihood strategies under the three pillars of sustainability – economic, social and environmental. Relationships between key factors were analysed. The outcome showed that farming fulfils their basic need of food security, with self-sufficiency in terms of seeds, organic fertilisers and tools. Agriculture is almost totally non-monitized: crops are grown mainly for household consumption. However, the crux faced by the Khaling Rai community is the need to develop high value cash crops in order to improve their livelihoods while at the same time maintaining food security. Institutional support in this regard was found to be lacking. At the same time there is declining soil fertility and an expanding population, which results in smaller land holdings. The capacity to absorb risk is inhibited by the small size of the resource base and access only to small local markets. A two-pronged approach is recommended. Firstly, the formation of agricultural cooperative associations in the area. Secondly, through them the selection of key personnel to be put forward for training in the adoption of improved low-cost technologies for staple crops and in the introduction of appropriate new cash crops.

A geomatics-based approach for the derivation of the spatial distribution of sediment transport processes in periglacial mountain environments

Within this paper modern techniques such as satellite image analysis and tools provided by geographic information systems (GIS.) are exploited in order to extend and improve existing techniques for mapping the spatial distribution of sediment transport processes. The processes of interest comprise mass movements such as solifluction, slope wash, dirty avalanches and rock- and boulder falls. They differ considerably in nature and therefore different approaches for the derivation of their spatial extent are required. A major challenge is addressing the differences between the comparably coarse resolution of the available satellite data (Landsat TM/ETM+, 30 in x 30 m) and the actual scale of sediment transport in this environment. A three-stepped approach has been developed which is based on the concept of Geomorphic Process Units (GPUs): parameterization, process area delineation and combination. Parameters include land cover from satellite data and digital elevation model derivatives. Process areas are identified using a hierarchical classification scheme utilizing thresholds and definition of topology. The approach has been developed for the Karkevagge in Sweden and could be successfully transferred to the Rabotsbekken catchment at Okstindan, Norway using similar input data. Copyright (C) 2008 John Wiley & Sons, Ltd.

Quantifying sediment transport processes in periglacial mountain environments at a catchment scale using geomorphic process units

The research record on the quantification of sediment transport processes in periglacial mountain environments in Scandimvia dates back to the 1950s. A wide range of measurements is. available, especially from the Karkevagge region of northern Sweden. Within this paper satellite image analysis and tools provided by geographic information systems (GIS) are exploited in order to extend and improve this research and to complement geophysical methods. The processes of interest include mass movements such as solifluction, slope wash, dirty avalanches and rock-and boulder falls. Geomorphic process units have been derived in order to allow quantification via GIS techniques at a catchment scale. Mass movement rates based on existing Field measurements are employed in the budget calculation. In the Karkevagge catch ment. 80% of the area can be identified either as a source area for sediments or as a zone where sediments are deposited. The overall budget for the slopes beneath the rockwalls in the Karkevagge is approximately 680 t a(-1) whilst about 150 : a-1 are transported into the fluvial System.

Breeding distribution and population decline of globally threatened Grey-necked Picathartes Picathartes oreas in Mbam Minkom Mountain Forest, southern Cameroon

The Grey-necked Picathartes Picathartes oreas, considered 'Vulnerable', is an enigmatic ground-dwelling bird endemic to the central African equatorial rainforest and belongs to a family of only two species. Its distribution extends to the two Endemic Bird Areas within Cameroon (Guinea Congo forest biome and Cameroon mountain arc) and its population is thought to be in decline throughout its range due to increasing habitat fragmentation and disturbance. During March-April 2003 and June and October 2007 we surveyed Grey-necked Picathartes in the north-western region of the Mbam Minkom Mountain Forest. In January-March 2006 we surveyed the entire mountain range and found go breeding and 24 potential breeding sites, mostly located on the western slopes. From the complete survey, we estimated the population at 44 breeding individuals. Populations were highest in the north-west region but had apparently declined from 40 breeding individuals in 2003 to 20 in 2007. This region accounted for 41% of the entire population on the mountain range during the 2006 survey. The Mbam Minkom/Kala Important Bird Area was designated based on the presence of Grey-necked Picathartes but is under high pressure of imminent destruction from agricultural encroachment and illegal timber exploitation. These results have important implications for decision making in delimiting forest boundaries and core areas for protection in the development of management plans. We suggest possible remedial actions, appropriate repeatable methods for future monitoring and opportunities for community involvement in the management and conservation of the site.

Movements, activity patterns and home range of a female brown bear (Ursus arctos, L.) in the Rodopi Mountain Range, Greece

Movements and activity patterns of an adult radio-tagged female brown bear accompanied by her cubs were documented for the first time in Rodopi area (NE Greece) from August 2000 to July 2002. Average daily movements were 2.45 +/- 2.26 SD km, (range 0.15-8.5 km). The longest daily range could be related to human disturbance (hunting activity). The longest seasonal distance (211 km), during Summer 2001 coincided with the dissolution of the family. With cubs, the female was more active during daytime (73 % of all radio-readings) than when solitary (28 %). The female switched to a more crepuscular behaviour, after separation from the yearling (July 2001). According to pooled data from 924 activity - recording sessions, during the whole monitoring period, the female was almost twice as active during day time while rearing cubs (51 % active) than when solitary (23 %). The autumn and early winter home range size of the family was larger (280 km(2)) than after the separation from the cubs (59 km(2)). During the family group phase, home range size varied from 258 km(2) in autumn to 40 km(2) in winter (average denning period lasted 107 days : December 2000-March 2001). The bear hibernated in the Bulgarian part of the Rodopi Range during winters of 2001 and 2002.

Effect of mountain breeze in ventilating the city under calm and neutral atmospheric environment: Interaction of airflow structures and ventilation efficiency

Many modern cities locate in the mountainous areas, like Hong Kong, Phoenix City and Los Angles. It is confirmed in the literature that the mountain wind system developed by differential heating or cooling can be very beneficial in ventilating the city nearby and alleviating the UHI effect. However, the direct interaction of mountain wind with the natural-convection circulation due to heated urban surfaces has not been studied, to our best knowledge. This kind of unique interaction of two kinds of airflow structures under calm and neutral atmospheric environment is investigated in this paper by CFD approach. A physical model comprising a simple mountain and three long building blocks (forming two street canyons) is firstly developed. Different airflow structures are identified within the conditions of different mountain-building height ratios (R=Hm/Hb) by varying building height but fixing mountain height. It is found that the higher ventilation rate in the street canyons is expected in the cases of smaller mountain-building ratios, indicating the stronger natural convection due to increasing heated building surfaces. However, there is the highest air change rate (ACH) in the lowest-building-height case and most of the air is advective into the street canyon through the top open area, highlighting the important role played by the mountain wind. In terms of the ventilation efficiency, it is shown that the smallest R case enjoys the best air change efficiency followed by the highest R case, while the worst ventilative street canyons occur at the middle R case. In the end, a gap across the streets is introduced in the modeling. The existence of the gap can greatly channel the mountain wind and distribute the air into streets nearby. Thus the ACH can be doubled and air quality can be significantly improved.

The application of Regional Climate Model output for the simulation of high-mountain permafrost scenarios

This study investigates the possibilities and limitations of using Regional Climate Model (RCM) output for the simulation of alpine permafrost scenarios. It focuses on the general problem of scale mismatch between RCMs and impact models and, in particular, the special challenges that arise when driving an impact model in topographically complex high-mountain environments with the output of an RCM. Two approaches are introduced that take into account the special difficulties in such areas, and thus enable the use of RCM for alpine permafrost scenario modelling. Intended as an initial example, they are applied at the area of Corvatsch (Upper Engadine, Switzerland) in order to demonstrate and discuss the application of the two approaches, rather than to provide an assessment of future changes in permafrost occurrence. There are still many uncertainties and inaccuracies inherent in climate and impact models, which increase when driving one model with the output of the other. Nevertheless, our study shows that the use of RCMs offers new and promising perspectives for the simulation of high-mountain permafrost scenarios

Amphibians and reptiles from a highly diverse area of the Caatinga domain: composition and conservation implications

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Investigation of the genetic diversity of domestic Capra hircus breeds reared within an early goat domestication area in Iran

Background: Iran is an area of particular interest for investigating goat diversity. Archaeological remains indicate early goat domestication (about 10 000 years ago) in the Iranian Zagros Mountains as well as in the high Euphrates valley and southeastern Anatolia. In addition, mitochondrial DNA data of domestic goats and wild ancestors (C. aegagrusor bezoar) suggest a pre-domestication management of wild populations in southern Zagros and central Iranian Plateau. In this study genetic diversity was assessed in seven Iranian native goat breeds, namely Markhoz, Najdi, Taleshi, Khalkhali, Naini, native Abadeh and Turki-Ghashghaei. A total of 317 animals were characterized using 14 microsatellite loci. Two Pakistani goat populations, Pahari and Teddy, were genotyped for comparison.Results: Iranian goats possess a remarkable genetic diversity (average expected heterozygosity of 0.671 across loci, 10.7 alleles per locus) mainly accounted for by the within-breed component (G(ST) = 5.9%). Positive and highly significant F-IS values in the Naini, Turki-Ghashghaei, Abadeh and Markhoz breeds indicate some level of inbreeding in these populations. Multivariate analyses cluster Iranian goats into northern, central and western groups, with the western breeds relatively distinct from the others. Pakistani breeds show some relationship with Iranian populations, even if their position is not consistent across analyses. Gene flow was higher within regions (west, north, central) compared to between regions but particularly low between the western and the other two regions, probably due to the isolating topography of the Zagros mountain range. The Turki-Ghashghaei, Najdi and Abadeh breeds are reared in geographic areas where mtDNA provided evidence of early domestication. These breeds are highly variable, located on basal short branches in the neighbor-joining tree, close to the origin of the principal component analysis plot and, although highly admixed, they are quite distinct from those reared on the western side of the Zagros mountain range.Conclusions: These observations call for further investigation of the nuclear DNA diversity of these breeds within a much wider geographic context to confirm or re-discuss the current hypothesis (based on maternal lineage data) of an almost exclusive contribution of the eastern Anatolian bezoar to the domestic goat gene pool.

Experimental infection of the tick Amblyomma cajennense, Cayenne tick, with Rickettsia rickettsii, the agent of Rocky Mountain spotted fever

In the laboratory, Amblyomma cajennense (Acari: Ixodidae) (Fabricius) larvae, nymphs and adults were exposed to Rickettsia rickettsii by feeding on needle-inoculated animals, and thereafter reared on uninfected guinea pigs or rabbits. Regardless of the tick stage that acquired the infection, subsequent tick stages were shown to be infected (confirming transstadial and transovarial transmissions) and were able to transmit R. rickettsii to uninfected animals, as demonstrated by serological and molecular analyses. However, the larval, nymphal and adult stages of A. cajennense were shown to be partially refractory to R. rickettsii infection, as in all cases, only part of the ticks became infected by this agent, after being exposed to rickettsemic animals. In addition, less than 50% of the infected engorged females transmitted rickettsiae transovarially, and when they did so, only part of the offspring became infected, indicating that vertical transmission alone is not enough to maintain R. rickettsii in A. cajennense for multiple generations. Finally, the R. rickettsii-infected tick groups had lower reproductive performance than the uninfected control group. Our results indicate that A. cajennense have a low efficiency to maintain R. rickettsii for successive generations, as R. rickettsii-infection rates should decline drastically throughout the successive tick generations.

Mountain centered icefields in northern Scandinavia

Mountain centered glaciers have played a major role throughout the last three million years in the Scandinavian mountains. The climatic extremes, like the present warm interglacial or cold glacial maxima, are very short-lived compared to the periods of intermediate climate conditions, characterized by the persistence of mountain based glaciers and ice fields of regional size. These have persisted in the Scandinavian mountains for about 65% of the Quaternary. Mountain based glaciers thus had a profound impact on large-scale geomorphology, which is manifested in large-scale glacial landforms such as fjords, glacial lakes and U-shaped valleys in and close to the mountain range. Through a mapping of glacial landforms in the northern Scandinavian mountain range, in particular a striking set of lateral moraines, this thesis offers new insights into Weichselian stages predating the last glacial maximum. The aerial photograph mapping and field evidence yield evidence that these lateral moraines were overridden by glacier ice subsequent to their formation. The lateral moraines were dated using terrestrial cosmogenic nuclide techniques. Although the terrestrial cosmogenic nuclide signature of the moraines is inconclusive, an early Weichselian age is tentatively suggested through correlations with other landforms and stratigraphical archives in the region. The abundance and coherent spatial pattern of the lateral moraines also allow a spatial reconstruction of this ice field. The ice field was controlled by topography and had nunataks protruding also where it was thickest close to the elevation axis of the Scandinavian mountain range. Outlet glaciers discharged into the Norwegian fjords and major valleys in Sweden. The process by which mountain based glaciers grow into an ice sheet is a matter of debate. In this thesis, a feedback mechanism between debris on the ice surface and ice sheet growth is presented. In essence, the growth of glaciers and ice sheets may be accelerated by an abundance of debris in their ablation areas. This may occur when the debris cover on the glacier surface inhibits ablation, effectively increasing the glaciers mass balance. It is thus possible that a dirty ablation area may cause the glacier to advance further than a clean glacier under similar conditions. An ice free period of significant length allows soil production through weathering, frost shattering, and slope processes. As glaciers advance through this assemblage of sediments, significant amounts of debris end up on the surface due to both mass wastage and subglacial entrainment. Evidence that this chain of events may occur, is given by large expanses of hummocky moraine (local name Veiki moraine) in the northern Swedish lowlands. Because the Veiki moraine has been correlated with the first Weichselian advance following the Eemian, it implies a heavily debris charged ice sheet emanating from the mountain range and terminating in a stagnant fashion in the lowlands.

Perennial Snow and Ice Variations (2000-2008) in the Arctic Circumpolar Land Area from Satellite Observations

Perennial snow and ice (PSI) extent is an important parameter of mountain environments with regard to its involvement in the hydrological cycle and the surface energy budget. We investigated interannual variations of PSI in nine mountain regions of interest (ROI) between 2000 and 2008. For that purpose, a novel MODIS data set processed at the Canada Centre for Remote Sensing at 250 m spatial resolution was utilized. The extent of PSI exhibited significant interannual variations, with coefficients of variation ranging from 5% to 81% depending on the ROI. A strong negative relationship was found between PSI and positive degree-days (threshold 0°C) during the summer months in most ROIs, with linear correlation coefficients (r) being as low as r = −0.90. In the European Alps and Scandinavia, PSI extent was significantly correlated with annual net glacier mass balances, with r = 0.91 and r = 0.85, respectively, suggesting that MODIS-derived PSI extent may be used as an indicator of net glacier mass balances. Validation of PSI extent in two land surface classifications for the years 2000 and 2005, GLC-2000 and Globcover, revealed significant discrepancies of up to 129% for both classifications. With regard to the importance of such classifications for land surface parameterizations in climate and land surface process models, this is a potential source of error to be investigated in future studies. The results presented here provide an interesting insight into variations of PSI in several ROIs and are instrumental for our understanding of sensitive mountain regions in the context of global climate change assessment.