Journal Sciences News
The Saudi Dental Journal
February 2018
Inside Front Cover - Editorial Board Page/Cover image legend if applicable
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149

February 2018
Women in Drylands: Barriers and Benefits for Sustainable Livelihoods
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Sarab Abu-Rabia-Queder, Avigail Morris
February 2018
Vulnerability of women to climate change in arid and semi-arid regions: The case of India and South Asia
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): S.S. Yadav, Rattan Lal This article is a collation and synthesis of the literature review with the focus on the vulnerability of rural women in developing countries to climate change on the one hand and being pro-active in adapting to climate change on the other. The geographic coverage of the literature is global but with specific examples from India. The information presented in this paper is derived from diverse sources including journal articles and thematic books, and indicates severe adverse impacts not only on women's livelihood opportunities but also on exacerbating the workload and fatigue while decreasing their self esteem and forcing them to undertake some high risks and hazardous activities. The literature indicates that poverty, gender inequality, insecure land rights, heavy reliance on agriculture, less access to education and information are among the principal reasons for their vulnerability to climate change. The vulnerability is also confounded by the meager asset base, social marginalization, lack of mobility and exclusion from the decision-making processes in response to a disaster. However, the literature also shows that women are not only the passive victims of climate change but are also pro-active and agents of hope for adaptation to and mitigation of abrupt climate change. They utilize their experience and expertise to reduce the adverse impacts by adopting prudent strategies. They are also concerned about environmental issues, and are highly supportive of policies regarding environmental restoration. Large knowledge gaps exist regarding the vulnerability of women to changing and uncertain climate especially in arid regions. Authors of this article suggest some action plans and strategies to minimize vulnerability to climate change such as empowering women economically and educationally, organizing training and outreach programmes, and involving them in formal climate change mitigation and adaptation policies and programmes. Authors also outline research needed in order to identify and implement strategies regarding climate change. Collective and continuous efforts are critical to finding the sustainable solutions for this global phenomenon which is adversely impacting the most vulnerable but critically important members of the society.

Graphical abstract

image
February 2018
Women's food security and conservation farming in Zaka District-Zimbabwe
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Mediel Hove, Thomas Gweme Changes in rainfall patterns because of climate alteration amongst other factors contributed towards a decline in food security in Zimbabwe's Zaka District-Ward 31. In response, women in Ward 31 adopted conservation agriculture since the 2005/6 agricultural season to address food insecurity and other problems experienced in the crop production system. The research was designed to evaluate the extent to which conservation agriculture led to increased food security in the semi-arid area. The researchers used the mixed method approach and collected data through key informant interviews, Focus Group Discussions and observations. It was evident from the research that the farmers who practised conservation agriculture whilst correctly following most of the prescribed components and engaging the relevant strategies were able to increase their food security in the dry part of the district. It concludes that female farmers constrained by: fencing, long dry spells and labour were incapacitated to effectively implement conservation agriculture hence failed to attain food security.
February 2018
Purdah, purse and patriarchy: The position of women in the Raika shepherd community in Rajasthan (India)
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Ilse K
February 2018
Warlpiri experiences highlight challenges and opportunities for gender equity in Indigenous conservation management in arid Australia
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Jocelyn Davies, Jane Walker, Yiheyis Taddele Maru Gender equity has been recognized as a guiding principle for conservation management globally. Yet little attention is paid to gender in the design and implementation of many conservation programs including those in the vibrant and expanding arena of Australian Indigenous conservation partnerships. We examined the impact of gender in management of the Northern Tanami Indigenous Protected Area (IPA) in arid central Australia through qualitative research (interviews and participant observation) with senior Warlpiri women and men and members of the all-male Wulaign community-based ranger group. Senior men and women had many similar perspectives including that customary knowledge, skills and activities were important in managing country and were occurring less through the IPA's management partnerships than they would like. Additional challenges reported by women included lack of vehicles to access country. Senior men specifically called for greater gender equity in allocation of resources including establishment of a women's ranger group. These perspectives indicate that gender equity is a Warlpiri cultural norm for management of country. Differences between Indigenous women's and men's management of country elsewhere in arid Australia suggest that opportunities also exist for gender equity to enhance conservation outcomes. Prevalent belief systems in Australia, and many other developed countries, are gender blind in that they fail to recognize differences between men's and women's needs, interests, knowledges, behaviors and power. Monitoring of Australian Indigenous conservation programs shows that an increasing proportion of Indigenous community-based rangers are women. However factors that might explain and support this trend cannot be readily identified because little or no attention to gender is apparent in program design and project planning. Gender-aware design of conservation management policies, programs and projects is important for challenging and changing gender blindness. Brokers and bridging institutions, or ‘two-way’ approaches, have been important in progressing cross-cultural equity in the implementation of Australian Indigenous conservation partnerships and can be expected to be also valuable for promoting gender equity.
February 2018
Exploring the potential of household methodologies to strengthen gender equality and improve smallholder livelihoods: Research in Malawi in maize-based systems
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Cathy Rozel Farnworth, Clare M. Stirling, Amon Chinyophiro, Andrew Namakhoma, Rebecca Morahan Household methodologies (HHM) intervene directly in intra-household gender relations to strengthen overall smallholder agency and efficacy as economic agents and development actors. Strengthening women's agency is one mechanism for progressing towards collaborative, systemic farm management. It is expected this will contribute to improved farm resilience in the face of climate change, strengthen food and nutrition security, and improve other development indicators. HHM are built around a vision, gendered analysis of strengths, weaknesses, opportunities and threats (SWOT), an action plan, and indicators. Some HHM - including Gender Action Learning Systems (GALS), the focus of the research - use drawings making them easy to use for low-literate individuals. There is considerable evaluation report evidence of the efficacy of HHM in strengthening value chains, food security, and gender equality. However, this has yet to be complemented by a robust systematic evaluation of the methodology which includes non-intervention communities as controls. Here we report on the findings of a research study into GALS in Malawi where the National Smallholder Farmers' Association of Malawi (NASFAM) has been implementing GALS since 2013 with 4274 farmers (2821 women and 1453 men to May 2016). We held sex-disaggregated FGDs with 40 GALS households and 40 non-GALS households, all NASFAM members. Community profiles and a matrix activity focusing on task allocation, asset distribution, and expenditures by gender with 125 non-GALS and 135 GALS respondents were also conducted. Our analyses indicate a significant shift towards sharing of on-farm tasks and household tasks, and joint realization of the benefits from agricultural produce in GALS households. They are building up portfolios of assets including livestock, houses, ox-carts, and land, unlike non-GALS households. Respondents in GALS households, particularly de facto women-headed households, report an increase in social standing and participation in community life. In both GALS and non-GALS households, men and women agree that men continue to dominate marketing and are final decision-makers. However, financial transparency and intra-household agreement on expenditures characterize households with GALS participants.
February 2018
The connective strategies of Bedouin women entrepreneurs in the Negev
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Aleksandra Biernacka, Sarab Abu-Rabia-Queder, Gideon M. Kressel The study examines various forms of entrepreneurship of the Negev Bedouin women, mostly within the urban settings, in order to determine strategies applied in their entrepreneurial development. The analysis is based on semi-structured interviews with 28 women entrepreneurs, interviews with representatives of institutions supporting entrepreneurship and on participatory observations. The research draws on existing ethnic entrepreneurship theories and the family-embeddedness perspective, which allows for consideration of the relation between economic processes and family system characteristics and transformations which occur simultaneously and have reciprocal impact. The Bedouin women entrepreneurs are found to operate mainly within their urban ethnic enclaves, whereby difficult economic conditions combined with gender pressures create a mostly informal sector that complements insufficiencies of the formal market. These women develop their businesses by applying specific patriarchal connectivity strategies, which were developed due to strong impact of familial factors, such as: transitions in family structure, accessibility to family financial and human resources, adherence to the social codes and values. The impact of the last factor is visible on two levels: gender-separation of economic activities and networks (products and services addressed to women and children) and different roles of male and female family members. Whereas female members become employees or assistants, the male members keep their patriarchal positions as protectors and facilitators between the social requirements and exigencies of the economic activities. The connective strategies of Bedouin women entrepreneurs aim strongly at fulfilling their social roles as women, mothers and wives within the patriarchal order and as such, they bridge the gap between the strategies that previously accommodated desert condition subsistence living and the exigencies of the market economy of their contemporary semi-urban desert environment.
February 2018
The suburbanization of rural life in an arid and rocky village in western Turkey
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Kimberly Hart In this longitudinal and qualitative study of rural life in western Turkey, I argue that ecological conditions, state policies, and villagers’ agency play a significant role in the suburbanization of villages. This paper traces the history of how villagers in the Yuntda
Available online 11 January 2018
The economy of survival: Bedouin women in unrecognized villages
Publication date: February 2018
Source:Journal of Arid Environments, Volume 149 Author(s): Sarab Abu-Rabia-Queder, Avigail Morris, Heather Ryan This paper problematizes the binary division between substantivist vs formalist approaches, and suggests instead that in the case at Bedouin women living in unrecognized villages, within a settler context, deprived from the equal rights for developing an appropriate “rational” economic systems, people turn to their limited local economic systems aiming to produce economic safety net for their economic survival. However, lacking the conditions for their maintenance, these sociocultural institutions do not provide a sufficient base to maintain their economic systems, thus they recreate their “economy of survival” systems.
Available online 11 January 2018
What has ecosystem service science achieved in Spanish drylands? Evidences of need for transdisciplinary science
Publication date: Available online 11 January 2018
Source:Journal of Arid Environments Author(s): Cristina Quintas-Soriano, Marina Garc
Available online 10 January 2018
Land degradation and gully development in arid environments deduced by mezzo- and micro-scale 3-D quantification – The Negev Highlands as a case study
Publication date: Available online 11 January 2018
Source:Journal of Arid Environments Author(s): Rachel Zweig, Sagi Filin, Yoav Avni, Amir Sagy, Amit Mushkin We study in this paper land degradation processes in arid environments that are leading to a major environmental change. These processes, which are mostly the outcome of gully development, have direct impact on agriculture potential, biomass degradation, and escalating desertification. Three representative sites within the Negev Highland, Israel, are studied by utilizing terrestrial laser scans to gain detailed spatial information, accurate estimations, and concisely document overarching trends. The resulting information allows us to thoroughly characterize and quantify the geomorphic and vegetative changes and to calibrate rates and trends that have only been roughly estimated thus far. The scans, which were taken over a four-year span (2009–2013), cover three different types of hydrological seasons and provide unique insights on development rates and subsequent ramifications. The characteristic progression of natural land degradation in the Negev Highlands and the techniques used to document and analyze it can be extended globally to regions undergoing similar transitions.
Available online 8 January 2018
Contrasting ecophysiology of two widespread arid zone tree species with differing access to water resources
Publication date: Available online 10 January 2018
Source:Journal of Arid Environments Author(s): Rachael H. Nolan, Tonantzin Tarin, Rizwana Rumman, James Cleverly, Kendal A. Fairweather, Sepideh Zolfaghar, Nadia S. Santini, Anthony P. O'Grady, Derek Eamus Arid environments can support the seemingly unlikely coexistence of species tolerant of, or sensitive to, dry soil moisture. Here, we examine water-use and carbon-gain traits in two widespread tree species in central Australia: Acacia aptaneura and Eucalyptus camaldulensis. The former has a shallow root distribution and relies on soil moisture, while the latter is groundwater dependent. We hypothesised that A. aptaneura would exhibit a suite of characteristics that confer tolerance to low soil moisture, in contrast to E. camaldulensis. Consistent with our hypotheses A. aptaneura was relatively more anisohydric than E. camaldulensis (seasonal leaf water potential of
Available online 6 January 2018
Identifying optimal remotely-sensed variables for ecosystem monitoring in Colorado Plateau drylands
Publication date: Available online 8 January 2018
Source:Journal of Arid Environments Author(s): Travis B. Poitras, Miguel L. Villarreal, Eric K. Waller, Travis W. Nauman, Mark E. Miller, Michael C. Duniway Water-limited ecosystems often recover slowly following anthropogenic or natural disturbance. Multitemporal remote sensing can be used to monitor ecosystem recovery after disturbance; however, dryland vegetation cover can be challenging to accurately measure due to sparse cover and spectral confusion between soils and non-photosynthetic vegetation. With the goal of optimizing a monitoring approach for identifying both abrupt and gradual vegetation changes, we evaluated the ability of Landsat-derived spectral variables to characterize surface variability of vegetation cover and bare ground across a range of vegetation community types. Using three year composites of Landsat data, we modeled relationships between spectral information and field data collected at monitoring sites near Canyonlands National Park, UT. We also developed multiple regression models to assess improvement over single variables. We found that for all vegetation types, percent cover bare ground could be accurately modeled with single indices that included a combination of red and shortwave infrared bands, while near infrared-based vegetation indices like NDVI worked best for quantifying tree cover and total live vegetation cover in woodlands. We applied four models to characterize the spatial distribution of putative grassland ecological states across our study area, illustrating how this approach can be implemented to guide dryland ecosystem management.
Available online 6 January 2018
Intraspecific leaf shape at local scale determines offspring characteristics
Publication date: Available online 6 January 2018
Source:Journal of Arid Environments Author(s): Estrella Pastor, Santiago Soliveres, Alberto Vilagrosa, Andreu Bonet Identifying the degree of adaptation to particular environmental constraints at small geographical scales (e.g., intra-population variability) is particularly valuable to select plant reproductive material in restoration projects. We analyzed possible differences among progeny characteristics of Quercus coccifera L. a species of interest in forest restoration under Mediterranean climates. The differences were tested among seeds and seedlings from two phenotypic groupings (small and large leaves) within one provenance under semi-arid climate. In addition, these seeds and seedlings were compared with those from a near population under contrasted climate (i.e., subhumid climate). We analyzed differences in germination, growth and seedling morphological traits (height, number of leaves and canopy area). We considered the different characteristics of the progeny across different parent individuals, intra- and inter-population levels. We found seed provenance effects on germination and seedling morphology at different scales. Progenies from semi-arid populations and from parent plants with a smaller leaf size showed lower germination rates and lower development of above-ground structures (shoots and leaves). Our results suggest that intrapopulation variability for phenotypic traits, such as leaf size, could influence offspring fitness. In addition, these morphological traits are easily identifiable by stakeholders and could be a useful tool to ensure early plant establishment in reforestation programs.
Available online 4 January 2018
Quantifying multi-scale pastoral mobility: Developing a metrics system and using GPS-Tracking data for evaluation
Publication date: Available online 6 January 2018
Source:Journal of Arid Environments Author(s): Chuan Liao Mobility appears to be in decline in modern pastoralism, but measurement of mobility has been ambiguous. This paper develops a metrics system to evaluate multi-scale pastoral mobility, and uses continuous, frequent, cross-season GPS-tracking data to investigate movement patterns in five pastoral communities in southern Ethiopia. The metrics system includes both broad-scale indicators such as home range and number of camps, and fine-scale indicators such as herding loop length, daily maximum distance from camp, and angular distribution of observed cow locations. The findings suggest pastoral mobility patterns are highly heterogeneous, and there are clear trade-offs among different mobility indicators in pastoralists’ herding strategies. In contrast to conventional understanding that mobility declines when pastoralists settle down, I find evidence of sedentarized pastoralists engaging in more rigorous fine-scale movement than those who keep practicing camp relocation. Thus, pastoral mobility cannot be generalized according to any single indicator, and comprehensive evaluation is necessary to advance our understanding of pastoral mobility as a complex strategy to manage herds in the arid and semi-arid environments.
Available online 3 January 2018
Analyzing root traits to characterize juniper expansion into rangelands
Publication date: Available online 4 January 2018
Source:Journal of Arid Environments Author(s): K.A. Chesus, T.W. Ocheltree Juniper expansion into sagebrush-dominated communities is a phenomenon occurring across large regions of the western U.S. in the past century. We investigated the competitive abilities for belowground resources of Juniperus osteosperma (Utah juniper) and Artemisia tridentata (big sagebrush) based on fine root traits and spatial patterns of water uptake inferred from stem and soil stable oxygen isotopes (
January 2018
Anthropogenic food subsidies change the pattern of red fox diet and occurrence across Trans-Himalayas, India
Publication date: Available online 3 January 2018
Source:Journal of Arid Environments Author(s): Hussain S. Reshamwala, Shivam Shrotriya, Bhaskar Bora, Salvador Lyngdoh, Rodolfo Dirzo, Bilal Habib The anthropogenic food subsidy in the diet of animal populations is known to have negative ecological and physiological impacts on wildlife. The red fox (Vulpes vulpes), a generalist species living close to human habitation, often has access to garbage dumps. We studied the dietary pattern of red fox in the cold desert of the Trans-Himalayas in India, where natural resources are limited. We analysed a total of 1264 scats across six representative sites and examined red fox occurrences as a response to the availability of anthropogenic subsidies. We found that human subsidies contribute substantially (maximum 55.87%) to red fox diet. Red fox occurrence significantly increased with the increase in consumption of the food items originating from human subsidies (R2
January 2018
Inside Front Cover - Editorial Board Page/Cover image legend if applicable
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148

January 2018
Different microhabitats have contrasting effects on the spatial distribution of tree regeneration density and diversity
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Shaieste Gholami, Latifeh Saadat, Ehsan Sayad Spatial distribution of tree recruitment has been shown to be largely affected by microhabitats. If we are to preserve the distribution and abundance of tree regeneration in the face of environmental changes, we need to consider the microhabitats characterizing their recruitment process. We investigated the effect of type of microhabitat on the regeneration distribution of four tree species presence in the Zagros forests of western Iran. Regeneration density and diversity were found to be highly dependent on microhabitat. Regeneration density of Quercus brantii and Ceracus microcarpa was higher in heterospecific microhabitats. The highest density of regeneration occurred in the Crataegus pontica microhabitat, which covered 10.5% of the area. This study found that specific microhabitats affected the spatial patterns of tree regeneration in Zagros forests. Recruitment was restricted to those microhabitats under which environmental conditions constituted safe sites for regeneration. The Crataegus pontica microhabitat seems to have a major role in providing a safe site for regeneration in these forests. We suggest focusing restoration actions in Crataegus pontica microhabitats to better facilitate tree regeneration.
January 2018
Stable isotopes uncover trophic ecology of the West African crocodile (Crocodylus suchus)
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Xavier Santos, Sandra Navarro, Jo
January 2018
Pliocene-Pleistocene waterbodies and associated deposits in southern Israel and southern Jordan
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Hanan Ginat, Stephan Opitz, Linah Ababneh, Galina Faershtein, Michael Lazar, Naomi Porat, Steffen Mischke This paper provides an in-depth review of evidence for the presence of twelve waterbodies spanning the Late Pliocene through Late Pleistocene in southern Israel and southern Jordan. A comprehensive description of these waterbodies is presented, combined with new field, paleontological and numerical age data, along with a discussion of their implications for paleohydrology and paleoclimate. The region is currently hyper-arid and there are no permanent rivers, wetlands or lakes in the area. Nevertheless, during the time-frame examined, continuous layers of limestones and mudstones were deposited in wetlands and shallow lakes. According to their location, the waterbodies were classified into either resulting from local tectonic depressions or in wide natural depressions at base levels. Following the types of sediments and fauna associated with these waterbodies, it is suggested that four wetter periods occurred: Late Pliocene/Early Pleistocene, Middle Pleistocene, Middle Late Pleistocene and terminal Late Pleistocene. This resulted in the deposition of limestone, chalk, travertine, calcrete, mudstone, marl, clay, silt and sandstone. For several waterbodies, vertical and lateral transitions between white limestone and fine clastic sediments rich in carbonate, indicate changes in depositional conditions from a shallow lake to a wetland, both associated with wetter hydrological settings compared to current climatic conditions.
January 2018
Stabilization of calcareous sand dunes using phosphoric acid mulching liquid
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Hooshang Katebi, Ahmad Fahmi, Hossein Samadi Kafil, Masoud Hajialilue Bonab The water level reduction of Urmia Lake in the northwest of Iran has led to the shrinking of the lake area, exposure of the salt in the dried areas, desertification of shorelines, and creation and development of sand dunes in some coastal areas, especially Jabal Kandi region. The sand particles of these dunes are smaller than 300 
January 2018
Isotope stratigraphy: Insights on paleoclimate and formation of nitrate deposits in the Atacama Desert, Chile
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Erik B. Melchiorre, James O. Sickman, Becky C. Talyn, James Noblet Arid environment nitrate deposits are economically important and analogous to Martian environments, but their formation is poorly understood. Detailed N, O, and C isotope stratigraphy suggests Atacama Desert nitrate deposits form abiologically by differential leaching during hyperaridity (precipitation <2 mm/year). Nitrate deposit chemo-stratigraphy (top - bottom) shows sulfate depletion from 25.5 wt.% to 1.5 wt.%, and nitrate enrichment similar to ore deposit leaching models from 0.7 wt.% to 6.5 wt.%. The inverse relationship with depth of nitrogen (
January 2018
A social-ecological typology of rangelands based on rainfall variability and farming type
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): John-Oliver Engler, David J. Abson, Robert Feller, Jan Hanspach, Henrik von Wehrden We present a social-ecological typlogy for the world's rangelands that integrates the much debated non-equilibrium concept from ecology with socio-economic characteristics of rangeland systems. We propose that, as a first approximation, the socio-economic properties can be adequately captured and differentiated by the distinction between the two main types of rangeland farming systems worldwide: subsistence and commercial farming. The resulting typology has four categories, which are ‘commercial equilibrium’, ‘commercial non-equilibrium’, ‘subsistence equilibrium’ and ‘subsistence non-equilibrium’. We provide and discuss examples for each category. Moreover, we point out how this typology might help to understand and address some of the problems related to unsustainable rangeland management. Finally, we provide and discuss a global map of rangelands that illustrates the geographic distribution of all four rangeland types.
January 2018
Effects of alternating temperature on cactus seeds with a positive photoblastic response
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): L. Lindow-L
January 2018
Factors influencing colonisation processes in two contrasting mine sites in the Namib Desert
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Antje Burke I investigated vegetation recovery in a uranium mine in the central Namib and a diamond mine in the southern Namib to better understand natural recovery processes in arid areas. Environmental variables influencing colonisation processes were investigated using multivariate analyses to examine the relative importance of environmental variables on vegetation recovery at the two mines. Disturbance level was the most important variable influencing colonisation processes in the central Namib whereas distance to seed source was the most important in the southern Namib. At both mines, the proximity of a species pool to the disturbed areas (reference species pool) was more important than the pool of available species in the broader ecological community in which the mines were located (ecological species pool). The study indicates that merely relying on spontaneous, natural recovery is insufficient in the Namib if (1) pre-mining conditions are the restoration goal and (2) presently undisturbed or well recovered areas in the mine cannot be preserved as a suitable seed sources in the southern Namib. Appropriate completion criteria need to be developed that consider local conditions in order to ensure that restoration of mines in arid areas is realistic.
Available online 27 December 2017
Landscape-scale processes influence riparian plant composition along a regulated river
Publication date: January 2018
Source:Journal of Arid Environments, Volume 148 Author(s): Emily C. Palmquist, Barbara E. Ralston, David M. Merritt, Patrick B. Shafroth Hierarchical frameworks are useful constructs when exploring landscape- and local-scale factors affecting patterns of vegetation in riparian areas. In drylands, which have steep environmental gradients and high habitat heterogeneity, landscape-scale variables, such as climate, can change rapidly along a river's course, affecting the relative influence of environmental variables at different scales. To assess how landscape-scale factors change the structure of riparian vegetation, we measured riparian vegetation composition along the Colorado River through Grand Canyon, determined which factors best explain observed changes, identified how richness and functional diversity vary, and described the implications of our results for river management. Cluster analysis identified three divergent floristic groups that are distributed longitudinally along the river. These groups were distributed along gradients of elevation, temperature and seasonal precipitation, but were not associated with annual precipitation or local-scale factors. Species richness and functional diversity decreased as a function of distance downstream showing that changing landscape-scale factors result in changes to ecosystem characteristics. Species composition and distribution remain closely linked to seasonal precipitation and temperature. These patterns in floristic composition in a semiarid system inform management and provide insights into potential future changes as a result of shifts in climate and changes in flow management.
Available online 24 December 2017
Changes in soil hydraulic properties, soil moisture and water balance in Acacia senegal plantations of varying age in Sudan
Publication date: Available online 27 December 2017
Source:Journal of Arid Environments Author(s): Wafa E. Abaker, Frank Berninger, Mike Starr The effects of Acacia senegal trees on soil moisture (SM) and hydraulic properties in relation to plantations age and associated changes in soil organic carbon (SOC) were investigated and compared to grasslands at two sites in Sudan. Soil hydraulic properties were computed using pedotransfer functions based on texture and SOC, and SM measured using TDR. The measured SM data was used to parametrize a simple daily water balance model in which Hortonian runoff was calculated using the SCS runoff curve number (CN) method and evapotranspiration calculated using crop coefficients, K c , adjusted to seasonal values using NDVI. Measured SM was higher in the grasslands than plantations, but increased with plantation age, reflecting a similar trend in plantation SOC and plant available water capacities. The modelling resulted in lower runoff from the plantations, increased infiltration, evapotranspiration, reduced drainage and lower SM, as shown by measurements. Greater SM contents in the grasslands were attributed to lower evapotranspiration and resulted in greater drainage fluxes compared to the plantations. The study highlighted the need for more empirical studies on the effect of tree density and cover on rainfall-runoff relationships, infiltration, evapotranspiration and drainage in drylands, especially those of the drier parts of semi-arid Africa.
Available online 21 December 2017
Evaluation of remote sensing precipitation estimates over Saudi Arabia
Publication date: Available online 24 December 2017
Source:Journal of Arid Environments Author(s): Rebeka Sultana, Nasrin Nasrollahi The goal of this study is to evaluate five global high-resolution satellite precipitation products (PERSIANN, PERISANN-CDR, TRMM-RT, TRMM-3B42, and CMORPH) in Saudi Arabia where only 29 rain gauges distributed in various parts of the country record daily rainfall. The satellite data are evaluated on a daily and monthly scale and at a 0.25° x 0.25° spatial resolution from January 2003 to December 2011. The satellite products are further assessed in the western and eastern parts of the country where most of the rain falls during the wet season (November through April). Evaluation of the satellite products at the western and eastern gauges shows that most of the products perform better in estimating rainfall during the wet season but perform poorly at the eastern gauges during the dry season (June to September). PERSIANN-CDR improves rainfall estimates at some locations while PERSIANN performs better at others. TRMM-3B42 exhibits better performance than TRMM-RT at all sites. Overall, in terms of most of the statistical metrics, CMORPH, PERSIANN-CDR and TRMM-3B42 performed better over Saudi Arabia. These results suggest that the satellites using both TIR and PM data for rainfall estimates do not essentially improve rainfall measurements over the satellite using PM data alone.
Available online 18 December 2017
Leaf thickness and density drive the responsiveness of photosynthesis to air temperature in Mediterranean species according to their leaf habitus
Publication date: Available online 21 December 2017
Source:Journal of Arid Environments Author(s): Loretta Gratani, Laura Varone, Maria Fiore Crescente, Rosangela Catoni, Carlo Ricotta, Giacomo Puglielli The responsiveness of net photosynthetic rate (Aa) to mean monthly air temperature (TM) of eight Mediterranean evergreen species was investigated by analyzing the inter-annual changes in leaf mass area (LMA), leaf tissue density (LTD) and leaf thickness (LT). We wanted to test if species leaf habitus affected this response. To hit the goal, a multi-year dataset from our previously published papers was used. The inter-annual variability in LMA, LTD and LT was assessed by their coefficients of variation (CVs). Aa sensitivity to TM (SAa) was quantified by the slope of the species-specific relationships Aa-TM. A Principal Component Analysis (PC) was carried to identify the leaf morphological variation patterns across species. SAa was affected by the coordination of LTD and LT across species and this coordination depended on leaf habitus. The relationship between CVs and SAa revealed that only evergreen sclerophyllous with a longer leaf life-span rely on the inter-annual changes in LTD and LT to modulate their SAa. Overall, the results showed that the inter-annual LTD and LT variability affected the responsiveness of net photosynthetic rate of the selected species according to their leaf habitus.
Available online 16 December 2017
Human-carnivore interaction in a context of socio-productive crisis: Assessing smallholder strategies for reducing predation in North-west Patagonia, Argentina
Publication date: Available online 18 December 2017
Source:Journal of Arid Environments Author(s): P.G. G
Available online 11 December 2017
Statistical analysis of Asiatic cheetah movement and its spatio-temporal drivers
Publication date: Available online 16 December 2017
Source:Journal of Arid Environments Author(s): Faridedin Cheraghi, Mahmoud Reza Delavar, Farshad Amiraslani, Seyed Kazem Alavipanah, Eliezer Gurarie, William F. Fagan We analyzed the movement behavior of a male Asiatic cheetah (Acinonyx jubatus venaticus), a critically endangered species, to understand its habitat preferences and relationship to its ambient environment. Using a hidden Markov chain approach, we identified distinct behavioral phases within the cheetah's movement track. We explored the conditions under which the cheetah switched between these behavioral phases. We computed summary statistics of the displacement and duration for the portion of time that the animal had constant behavior and found a linear pattern between its displacement and duration per behavioral phases. We then employed resource-selection and step-selection approaches to understand the cheetah's habitat preferences in general. The cheetah preferred intermediate elevations, low to intermediate slopes, intermediate distances from villages and shorter distances to the water resources. The cheetah moved over a range of 1137
Available online 9 December 2017
Using germination prediction to inform seeding potential: II. comparison of germination predictions for cheatgrass and potential revegetation species in the Great Basin, USA
Publication date: Available online 11 December 2017
Source:Journal of Arid Environments Author(s): Nathan L. Cline, Bruce A. Roundy, Stuart Hardegree, William Christensen Germination models predict germination timing under seedbed water potential and temperature conditions. Using a wet thermal time model for germination prediction, we estimated progress toward germination (PTG) of 31 seedlots (10 species) as a function of hourly seedbed temperature (>0 °C) when soils were above a water potential of
Available online 9 December 2017
Effects of propagule pressure and priority effects on seedling recruitment during restoration of invaded grassland
Publication date: Available online 9 December 2017
Source:Journal of Arid Environments Author(s): Merilynn C. Schantz, Roger L. Sheley, Jeremy J. James High disturbance frequency, low water availability, and advantageous growth mechanisms of invasive annual compared to native perennial grasses reduce native grass establishment throughout arid rangelands. Modifying seeding dispersal processes, including seeding rate and time, may increase native grass recruitment by influencing safe site occupation. A better understanding of seedling development through life history stages and the ecological processes occurring during these stages may be necessary to comprehend modified dispersal dynamics on plant community assembly. We tested the effects of spring vs. fall annual grass seeding times, adding water, and varying annual and perennial grass propagule pressure on perennial and annual grass recruitment in an eastern Oregon shrub-steppe ecosystem. Across species, survival rates were lowest between germination and emergence stages. However, perennial grass germination rates were highest when perennials were seeded with annual grasses in autumn. Perennial grass recruitment was generally low, especially when annual grass propagule pressure was higher than 150 seeds m
Available online 8 December 2017
Economic and environmental rehabilitation through soil and water conservation, the case of Tigray in northern Ethiopia
Publication date: Available online 9 December 2017
Source:Journal of Arid Environments Author(s): Gebremedhin Gebremeskel, T.G. Gebremicael, Abbadi Girmay The natural resources in the semi-arid area of Tigray, northern Ethiopia, have been exploited for years. This has caused severe land degradation, which in turn led to recurrent drought and poverty. To recover the degraded lands, soil and water conservation (SWC) interventions were given a policy attention since the 1970s. Starting 1990s, SWC-based integrated catchment management (ICM) implementation programmes, complemented by conservation-based agricultural development strategy, have been implemented. Many studies on ICM interventions and associated benefits have been reported so far. However, as most of the studies were conducted on experimental plots/small catchment scale, none of them have attempted to report the achievements and lessons at large scale. Hence, a comprehensive review is needed to explore and publicize the interventions and associated benefits. This review was conducted through detailed analysis of evidence and facts from literature, field observations and farmers’ perceptions. The reviewed literature explicitly showed that ICM interventions have been successful in Tigray. Collective evidence has shown that most of the degraded landscapes are considerably restored, of which the soil fertility, availability of water, and rainfed and irrigated crop productivity have significantly increased over the last two decades. Consequently, environmental, ecological and socio-economic changes have been observed when compared to pre-implementation of ICM. Despite these achievements, some interventions often suffer from over-ambition, upward accountability and a top-down approach. Failures of Horeye and roof water harvesting, mismanagement of fertilisers, low survival of tree seedlings and lack of income from exclosures can be considered pitfalls that may affect the sustainability of the achievements. An important lesson drawn from Tigray is the participation of all stakeholders and the strong commitment and sense of ownership by the people and local government, which many projects lack worldwide. Observed experiences, achievements and implementation pitfalls can provide a lesson to other regions with similar agro-ecological, environmental and socio-economic setups.
Available online 6 December 2017
Using germination prediction to inform seeding potential: I. Temperature range validation of germination prediction models for the Great Basin, USA
Publication date: Available online 8 December 2017
Source:Journal of Arid Environments Author(s): Nathan L. Cline, Bruce A. Roundy, William F. Christensen Wet thermal germination regression models predict when subpopulations of seeds will germinate based on the summation of thermal time when seedbed soil water potential > 
Available online 6 December 2017
Less impacted or simply neglected? Anuran mortality on roads in the Brazilian semiarid zone
Publication date: Available online 6 December 2017
Source:Journal of Arid Environments Author(s): Angeliane do Nascimento Pereira, Cecilia Calabuig, Milena Wachlevski Amphibians are among the vertebrates most affected by collisions on highways, although the extent of this impact on amphibian populations is usually underestimated by standard survey methods. Specifically in semiarid regions, where rainfall is highly concentrated and unpredictable, large numbers of anurans disperse to reproduce, increasing the risk of mass mortality. In the present study, we evaluated temporal variation in anuran mortality rates on highways in the Brazilian semiarid zone, and the influence of survey technique on the detectability of roadkill anurans. We monitored stretches of two highways in the Brazilian semiarid zone using vehicular and foot surveys over a one-year period. Anuran mortality was positively related with rainfall and was concentrated at the peak of the rainy period, reflecting the high rates of dispersal occurring during the breeding season. Anurans were detected 25 times more frequently during foot than vehicular surveys, and only relatively larger bodied-sized species were detected during vehicular searches. We conclude that anurans suffer high rates of mortality during short periods of the rainy season in the Brazilian semiarid zone, and, while vehicular searches can sample larger transects more rapidly, although they significantly underestimate roadkill anuran mortality in comparison to foot surveys.
December 2017
Differences in the structure of the bat community between a cloud forest refuge and a surrounding semi-arid Caatinga scrubland in the northeastern Brazil
Publication date: Available online 6 December 2017
Source:Journal of Arid Environments Author(s): Patr
December 2017
Inside Front Cover - Editorial Board Page/Cover image legend if applicable
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147

December 2017
Natural resource opportunities and challenges for rural development in marginal grabens – The state of the art with implications for the Rift Valley system in Ethiopia
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Hailemariam Meaza, Amaury Frankl, Jean Poesen, Amanuel Zenebe, Jozef Deckers, Veerle Van Eetvelde, Biadgilgn Demissie, Tesfaalem Ghebreyohannes Asfaha, Jan Nyssen With increasing global population, the production of more food and fiber has led to an expansion of the areas under cultivation, of which low-lying flat areas (including marginal graben bottoms) are of particular interest. Marginal grabens have been the center of agricultural development around the world. This paper examines the opportunities and challenges related to natural resources in rural development and highlights the knowledge gaps and priorities for the research and development of marginal grabens with specific reference to Ethiopia's Rift Valley marginal grabens, which have sufficient land banks to accommodate irrigated agriculture. Repeated transect walks, focus group discussions and interviews carried out in Northern Ethiopia, have been employed to address these research questions, while content analyses and descriptive statistics have been used to analyze the data. This paper shows that marginal grabens are rich in blue and green waters due to their topographical and geological characteristics, and are fertile plains suitable for irrigated agriculture. However, marginal grabens can reach closing and closed basin status in arid and semi-arid environments. Salinization, waterlogging, incisions and sedimentation also threaten the livelihoods of smallholder farmers in the grabens. Thus, appropriate river basin governance, integrated land management, and wise water allocation is needed to optimize land and water resources during rural development in the (semi)closed marginal grabens of northern Ethiopia and elsewhere in the world with similar geographical settings.
December 2017
Germination response to light and temperature in eight annual grasses from disturbed and natural habitats of an arid Arabian desert
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Ali El-Keblawy It has been hypothesized that annuals of unpredictable arid deserts produce dormant seeds as a strategy for risk spreading, but weedy annuals have lower dormancy and positively photoblastic seeds. I tested this hypothesis by comparing dormancy, and photoperiod and temperature requirements during germination in annual grasses of unpredictable arid deserts and other grasses from disturbed sites. Seeds were collected from four annual grasses of natural sandy deserts and other four from disturbed sites of an arid Arabian desert. Seeds were germinated in three incubators adjusted at daily night/day temperature regimes of three temperatures in both continuous darkness and alternating 12 h light/12 h darkness. The four sandy desert grasses had greater dormancy, compared to those of disturbed sites. Light and temperature ranges of germination were narrower and species specific for sandy desert grasses. Seeds of the grasses of disturbed sites germinated at wider range of temperatures and all were positively photoblastic, except Chloris virgata. Negative photoblastism was very rare, recorded only in seeds of Coelachyrum brevifolium at lower and moderate temperatures. Seed photoblastism depended more on habitat types than seed mass. The light and temperature requirements of the studied grasses can explain their adaptation and distribution in natural habitats.
December 2017
Interactions between seed functional traits and burial depth regulate germination and seedling emergence under water stress in species from semi-arid environments
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Luis Merino-Mart
December 2017
Shrubs facilitate pine colonization by controlling seed predation in dry Mediterranean dwarf shrublands
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Jotham Ziffer-Berger, Peter J. Weisberg, Mary E. Cablk, Yossi Moshe, Yagil Osem Spatial association between pine recruitment and shrubs is widely observed in dry environments and often associated with physical facilitation provided by the shrub, alleviating seedling drought stress. However, shrubs may also facilitate recruitment by sheltering seeds from granivores. In this study we investigated the influence of shrub-related microsites on post-dispersal pine seed survival in dry Mediterranean shrubland. We present a novel approach investigating the survival of single seeds in the context of long-distance wind dispersal. In four dry shrubland sites of central Israel, we placed seeds of Pinus halepensis in different microsites associated with Sarcopoterium spinosum shrubs: under canopy, at two margins and in between shrubs. We monitored the seed persistence monthly, replacing seeds removed by granivores. We also compared seed survival in burned vs. unburned areas. Logistic regression showed that seeds placed under shrubs had significantly higher survival rates than elsewhere. In unburned sites survival was higher than in burned sites and remained higher under shrub canopies. We show that these effects were substantial by considering the length of the season through which seeds need to persist. We conclude that shrubs constitute an important facilitator for Pinus halepensis colonization in dry shrubland through their positive effect on seed survival.
December 2017
How fast can conifers climb mountains? Investigating the effects of a changing climate on the viability of Juniperus seravschanica within the mountains of Oman, and developing a conservation strategy for this tree species
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Khalid A.A.Y. Al Farsi, Darach Lupton, James D. Hitchmough, Ross W.F. Cameron The conifer, Juniperus seravschanica is a keystone species within Oman, yet its decline is typical of other arid-adapted, montane tree species. This research aimed to identify causes of decline and subsequent viable conservation strategies; strategies that may have wider application for tree conservation. Decline in J. seravschanica is typified by foliar dieback and little regeneration via seed; traits most apparent at lower altitudes. The research evaluated the viability of seeds collected at three different altitudes: 2100–2220 m (Low), 2300–2400 m (Mid) and 2500–2570 m above sea level (High). In addition, seeds and young trees were planted at these altitudes and maintained under differential irrigation. Results showed that trees grown at Low altitude produced fewer, less-viable seed. Transplanting young trees proved more successful than seed sowing in re-establishing plants in the wild. Age of transplant had an effect, however, with 5-year-old stock showing greater survival (>97%) than 2-year-old trees. The younger trees only established well when planted at High altitude, or provided with irrigation at Mid/Low altitudes. Water availability did not entirely explain survival, and in some locations direct heat stress too may be limiting viability. Practical conservation measures include identifying genotypes with greater drought/heat tolerances and planting only more mature nursery trees.
December 2017
Combining ecological aspects and local knowledge for the conservation of two native mammals in the Gran Chaco
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Maria E. Periago, Daniela M. Tamburini, Ricardo A. Ojeda, Daniel M. C
December 2017
Effect of drought on demography of Pileated Finch (Coryphospingus pileatus: Thraupidae) in northeastern Brazil
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Jo
December 2017
Hydrodynamic numerical modelling of the water level decline in four temporary ponds of the Do
December 2017
Effects of tillage system on greenhouse gas fluxes and soil mineral nitrogen in wheat (Triticum aestivum, L.)-fallow during drought
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): Prakriti Bista, Urszula Norton, Rajan Ghimire, Jay B. Norton Recurring drought combined with intensive tillage may accelerate degradation of soils in a soil organic matter (SOM)-loss feedback that undermines agricultural sustainability of semiarid farming systems. Winter wheat (Triticum aestivum, L.) in Wyoming is grown on marginally productive soils and annual precipitation of less than 400 mm. Greenhouse gas (GHG) fluxes, soil nitrogen (N), global warming potential (GWP) and greenhouse gas intensity (GHGI) were monitored in no-till (NT), conventional tillage (CT, four tillage operations), and chemical-free (CF, six tillage operations) for 27 months beginning in May 2011. Severe drought started in April 2012 and lasted 17 months. No-till best mitigated GHG emissions and accumulation of mineral N, emitting 25%–30% less nitrous oxide, 35% less carbon dioxide fluxes and retaining twice as much soil nitrate compared with CT and CF during drought in the summer of 2012. Net GWP and GHGI in NT were 32%–35% and 43% lower than in CT, respectively. NT was the only management system that maintained negative net GWP and GHGI values during the summer of 2013. As drought reduces the amount of residue inputs and SOM restorative processes, reducing tillage frequency and leaving more crop residue after harvest support more effective SOM protection during drought.

Quantifying riparian total evaporation along the Groot Letaba River: A comparison between infilled and spatially downscaled satellite derived total evaporation estimates
Publication date: December 2017
Source:Journal of Arid Environments, Volume 147 Author(s): S. Gokool, C. Jarmain, E. Riddell, A. Swemmer, R. Lerm, K.T. Chetty The use of satellite earth observation data for the estimation of evapotranspiration has been well documented and represents a viable approach for the quantification of riparian water use at landscape to regional scales. However, the trade-off between the spatial and temporal resolution associated with imagery can limit the reliability of satellite-based evapotranspiration modelling. This study investigated two approaches to quantify evapotranspiration at a moderate spatial resolution (30 m) on a daily time step, for a perennial river flowing through a semi-arid, savanna landscape. The Surface Energy Balance System (SEBS) Model was used to derive daily evapotranspiration from satellite imagery. The actual crop coefficient (Kc act ) and output downscaling with linear regression (ODLR) approaches were then evaluated by comparing their respective estimates against Eddy covariance (EC ET ) measurements at two locations. Comparisons of ET estimates acquired using the Kc act and ODLR approaches against EC ET , yielded RMSE values of; 1.88 and 2.57 mm d
view: 178

Discover the latest trends with our newest arrivals for men at Freshpair.com! Free Shipping on all US orders.

Start: 09 Aug 2017 | End: 01 May 2018

Save $150 on ALL Home and Home Office Laptops and Desktops when you spend over $1699.99 with coupon code: $150OFF$1700PC

Code: $150OFF$1700PC

Start: 01 May 2017 | End: 01 Mar 2018

10% Off Newsletter Sign Ups at Moda Operandi!

Start: 12 Sep 2017 | End: 01 Apr 2018

Search All Amazon* UK* DE* FR* JP* CA* CN* IT* ES* IN* BR* MX
Booking.com B.V. is based in Amsterdam in the Netherlands. Ready for some statistics? Our 1,534,024 properties, including 860,482 holiday rentals, are located in 123,105 destinations in 229 countries and territories, and are supported internationally by 198 offices in 70 countries.
2013 Copyright © Techhap.com Mobile version 2015 | PeterLife & company
Terms of use Link at is mandatory if site materials are using fully or particulary.
Were treated to the site administrator, a cup of coffee *https://paypal.me/peterlife
Yandex.ru