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Over the last 30 years, the description of microbial diversity has been mainly based on culture-independent approaches (metabarcoding and metagenomics) allowing an in-depth analysis of microbial diversity that no other approach allows. Bearing in mind that culture-dependent approaches cannot replace culture-independent approaches, we have improved an original method for isolating strains consisting of “culturing” grains of sand directly on Petri dishes (grain-by-grain method). This method allowed to cultivate up to 10% of the bacteria counted on the surface of grains of the three sites studied in the Great Western Erg in Algeria (Timoudi, Béni Abbès, and Taghit), knowing that on average about 10 bacterial cells colonize each grain. The diversity of culturable bacteria (collection of 290 strains) predicted by 16S rRNA gene sequencing revealed that Arthrobacter subterraneus, Arthrobacter tecti, Pseudarthrobacter phenanthrenivorans, Pseudarthrobacter psychrotolerans, and Massilia agri are the dominant species. The comparison of the culture-dependent and - independent (16S rRNA gene metabarcoding) approaches at the Timoudi site revealed 18 bacterial genera common to both approaches with a relative overestimation of the genera Arthrobacter/Pseudarthrobacter and Kocuria, and a relative underestimation of the genera Blastococcus and Domibacillus by the bacterial culturing approach. The bacterial isolates will allow further study on the mechanisms of tolerance to desiccation, especially in Pseudomonadota (Proteobacteria). [ABSTRACT FROM AUTHOR]

Micromorphological and ultrastructural data have been helpful in determining the evolution, classification, ecology and phylogeny of seed plants. Taxonomic utility of seed characters has been explored, although the value of micro-structure in selected dicot angiosperms from desert areas has not been adequately addressed. We conducted a comparative morphometric analysis of internal and external seed features in the 16 dicot species representing 10 families from the Thal desert (Pakistan) using scanning electron microscopy. Seeds were mostly minute and small and slightly larger than 1 mm in length except for Acacia nilotica, Astragalus hamosus and Prosopis juliflora. Seeds varied in shape from elliptical to obovate, D-shaped, reniform, rhomboid and ellipsoidal. The cell outline, periclinal boundaries and sculpture pattern of the anticlinal wall were generally rugulate, reticulate and striate, papillate and rugose or rarely undulating granulate. The seed coat also comprises diverse forms of epicuticular projections and texture. The phenetics of 84 character-states using principal component and dendrogram statistics supported the affinities among desert species. Here, we identified micromorphological similarities and differences among dicot angiosperms to determine their systematic relationships. [ABSTRACT FROM AUTHOR]

It was previously reported that afforestation in the desert can help improve soil texture, carbon accumulation, and nutrient status. However, the effects of afforestation on soil microbial composition, diversity, and microbial interactions with soil physicochemical properties have been rarely evaluated quantitatively. Using the method of space-for-time substitutions, we assessed the development and determinants of topsoil bacterial and fungal communities over nearly 40 years of successive afforestation by aerial sowing in Tengger Desert, China. The results showed that afforestation by aerial sowing comprised a considerable proportion of Chloroflexi and Acidobacteria in the bacterial community in addition to the ubiquitous phyla found in desert but had fewer effects on the dominant phyla of the fungal community. At the phylum level, the bacterial community was clearly clustered into two groups. However, it was difficult to differentiate the constituents of the fungal community based on principal coordinate analysis. The richness of the bacterial and fungal communities was significantly higher after five years than at zero years and three years. Additionally, the bacterial community varied parabolically and reached its largest size at twenty years, while the fungal community increased exponentially. Soil physicochemical properties were found to have divergent effects on the abundance and diversity of bacterial and fungal communities, among which salt- and carbon-associated properties (e.g., electrical conductivity, calcium, magnesium, total carbon, and organic carbon) were closely related with the abundance of bacterial-dominant phyla and the diversity of bacteria and fungi, but nutrient-associated properties (e.g., total phosphorus and available phosphorus) were not. The results indicate that afforestation through the salt secretions of plants leaves and carbon inputs from litter promote the development of topsoil bacterial and fungal communities in the desert. [ABSTRACT FROM AUTHOR]

A concern that people ought to be given what they deserve, in both positive and negative senses, lies deep within the human psyche. Views on the level of reward or punishment that a person deserves for their actions will differ across persons, places, and time, but, I argue in this article, depend substantively upon some combination of intentions and outcomes. Using these characteristics, I propose a taxonomy of actions, ordered from most to least blameworthy, with, for example, it being suggested that for any particular level of harm an intentional yet unrealized harm is more blameworthy than an unintentional yet realized harm (a similar taxonomy can be developed for the positive domain of praiseworthy actions). The taxonomy is focused upon people's actions toward others, but I finish the article with a discussion of desert in relation to people's intentions toward themselves. Ultimately, I contend that the strength and sustainability of public sector services and welfare systems, not to mention our private relationships, rely upon the recognition that desert underpins our notion of justice. [ABSTRACT FROM AUTHOR]

The aim of this research is to present how sand encroachment and dust fallout criteria impact the siting of hybrid wind – solar energy in hot desert regions. Analytical Hierarchy Process and Geographic Information System techniques were used to generate a hybrid wind – solar energy suitability map for Kuwait. For siting solar farms, dominant aeolian geomorphic processes like sand encroachment and dust fallout rate, distance to urban areas and farms, proximity to main roads and transmission lines, and slope criteria were used. Wind speed, distance to urban areas and farms, and proximity to main roads and transmission lines were considered for siting wind farms. According to the findings, sand encroachment and dust fallout rate were the top two criteria in terms of weighting for siting solar energy. The lowest hybrid suitability class covers the smallest area, with an area of 19 km2 of the study area, and is located in the south of the study area. The highest hybrid suitability class covers 1349 km2 and is located in the northeast, midwest, southeast, and south. The sensitivity analysis results demonstrate that sand encroachment and dust fallout rate have a significant role in siting hybrid wind – solar farms in hot desert regions. [ABSTRACT FROM AUTHOR]

Key message: Desert Acacia trees photosynthesize during the hot dry summer, and use stored carbon for summer growth. Trees that grow in hyper-arid environments can provide important insight into the role of carbon use and carbon storage for tree survival and growth in extreme conditions. Acacia trees, in particular, experience some of the most arid conditions in which trees can grow on the planet, enduring high temperatures, high radiation and drought. Here we measured for two years photosynthesis along the day, stem circumference growth, and seasonal changes in non-structural carbohydrates in adult Acacia trees in their natural hyper-arid habitat (Arava desert, southern Israel). The peak of net CO2 assimilation was at midday in all seasons, even during summer when vapor pressure deficit was at maximum of 6 kPa and light intensities were at high levels (1800 µmol photons m−2 s−1). Tree growth started in the spring and increased in the hot summer season and during the dry fall season (autumn). Starch concentrations in the branches were highest in the winter and spring (17% in dry matter) decreasing in the summer and fall (7% in dry matter). Our observations indicated that carbon assimilated during the winter was stored in the branches as starch reserves, which were later used for tree growth in summer. Still, most of the growth was subsidized by concurrent assimilation during the dry season. These findings show that Acacia trees are able to photosynthesize in conditions that other trees cannot, indicating a strong potential to contribute to ecosystem carbon sequestration in warming and drying climates. [ABSTRACT FROM AUTHOR]

The relationship between the purposes of sentencing and imprisonment can be variously conceptualized. The paper theorizes and contrasts two models of sentencing and prison relations—continuity and separation. The continuity model assumes continuity between sentencing and prison regime. Under this model, all sentencing purposes may impact prison regime. The separation model distinguishes between the purposes of sentencing and of imprisonment. Under the separation model, the retributive element of imprisonment is completely fulfilled by depriving the prisoner of liberty. Retributive considerations can affect only the duration of the sentence, while prison regime is determined solely according to rehabilitation/risk and prison security considerations. The paper problematizes the separation model as it suffers from two difficulties: (a) the idea that the retributive element of imprisonment is fully fulfilled by depriving the prisoner's liberty undermines the "hard treatment" element of the retributive punishment. Relatedly, since no prison regime can deprive a person solely of liberty no custodial sentence can be justified; (b) given the inability to isolate the denial of liberty as the only deprivation of imprisonment, the separation model also encourages judges to underestimate and feel less responsible for the full meaning of their decision to imprison. Finally, the paper will argue that liberal prison conditions may (and should) be achieved even when seeing retribution as relevant for prison life and will offer possible ways to do so. [ABSTRACT FROM AUTHOR]

The soil seed bank is an essential functional component of plant communities. In arid ecosystems, the island-like distribution of shrubs influences the spatial distribution of the soil seed bank. Very little is known about seed banks in deserts of the Middle East. The present study aimed to evaluate the facilitative effects of Haloxylon persicum shrubs on the soil seed bank of annual plants in a sandy desert region in northwestern Saudi Arabia during two consecutive growing seasons (2017–2018 and 2018–2019) with contrasting rainfall. A total of 480 soil samples at 12 stands were collected from two microhabitats, under shrubs and in open areas, soon after the two growing seasons. The germinable seed bank of annual plants was estimated by controlled seedling emergence method. Shrubs significantly facilitated the accumulation of seed bank beneath their canopies after the two growing seasons. In both microhabitats, the size and species richness of soil seed bank were significantly greater after the wet growing season (2018–2019) than following the dry season (2017–2018). The facilitative effects of shrubs were greater following the moister growing season than after the dry season. The effect of shrubs on seed bank–annual vegetation similarity varied between growing seasons, being greater in shrub interspaces than beneath shrub canopies for the dry growing season, while during the wet season, the similarity of the seed bank with standing annual vegetation was greater in sub-canopy microhabitat than in bare soil. [ABSTRACT FROM AUTHOR]

Several leading theorists embrace the Simple Desert Account of Discrimination. This account involves two claims: it claims that a mismatch between what people deserve, on the one hand, and what they get, on the other hand, is (a) integral to discrimination, and (b) wrong. I shall query (a). First, I challenge what I see as the principal, positive argument for the Simple Desert Account. Second, in some cases wrongful discrimination brings about a better match between desert and what people get. Situations in which this could be the case include those where: the discriminatee is a serial discriminator herself; the person wrongfully discriminated in favour of deserves greater advantages than she enjoys; by engaging in wrongful discrimination the discriminator reduces her moral deservingness and thereby the gap between her level of deservingness and her otherwise unfittingly low level of advantage. [ABSTRACT FROM AUTHOR]

Aim: Desert springs or oases are the only permanent mesic environments in highly water‐limited arid regions. Oases have immense cultural, evolutionary and ecological importance for people and a high number of endemic and relic species. Nevertheless, they are also highly vulnerable ecosystems, with invasive species, overexploitation and climate change being the primary threats. We used the arthropod communities' spatiotemporal diversity and distribution patterns as a proxy to understand biodiversity dynamics in two geographically close but ecologically contrasting and highly threatened ecosystems: deserts and oases. Location: Baja California Peninsula, Mexico. Methods: Arthropod communities at five oases and surrounding desert scrub areas were sampled in two seasons. Using DNA metabarcoding and traditional taxonomic surveys, we tried to identify what biotic and abiotic characteristics of the habitat are important drivers of arthropod diversity and how these characteristics can change across spatial and temporal scales. Results: Over 6200 individuals representing 23 orders were collected. In oasis samples, the community composition fluctuated more in space (i.e. among sites) than in time (i.e. seasons). Thus, seasonal changes did not affect oasis community diversity and composition, but the dissimilarity among sites increased with geographic distance. Moreover, anthropic activities negatively correlated with arthropod diversity in oases. On the other hand, the season, geography (e.g. latitude) and biotic characteristics of the habitat (e.g. sampled scrub species) significantly affected the diversity and composition of the desert arthropod communities. Main Conclusions: Neutral dynamics (e.g. historical climatic events, dispersal limitation and spatial component) and human impact significantly influenced the biodiversity patterns of each oasis. In contrast, the habitat's seasonal variation and biotic characteristics were the most important variables influencing the diversity of the desert communities. Baja California oases harbour distinct invertebrate communities; therefore, each oasis should be conserved individually to preserve these unique assemblages. [ABSTRACT FROM AUTHOR]

Monitoring trends in animal populations in arid regions is challenging due to remoteness and low population densities. However, detecting species' tracks or signs is an effective survey technique for monitoring population trends across large spatial and temporal scales. In this study, we developed a simulation framework to evaluate the performance of alternative track‐based monitoring designs at detecting change in species distributions in arid Australia. We collated presence–absence records from 550 2‐ha track‐based plots for 11 vertebrates over 13 years and fitted ensemble species distribution models to predict occupancy in 2018. We simulated plausible changes in species' distributions over the next 15 years and, with estimates of detectability, simulated monitoring to evaluate the statistical power of three alternative monitoring scenarios: (1) where surveys were restricted to existing 2‐ha plots, (2) where surveys were optimized to target all species equally, and (3) where surveys were optimized to target two species of conservation concern. Across all monitoring designs and scenarios, we found that power was higher when detecting increasing occupancy trends compared to decreasing trends owing to the relatively low levels of initial occupancy. Our results suggest that surveying 200 of the existing plots annually (with a small subset resurveyed twice within a year) will have at least an 80% chance of detecting 30% declines in occupancy for four of the five invasive species modeled and one of the six native species. This increased to 10 of the 11 species assuming larger (50%) declines. When plots were positioned to target all species equally, power improved slightly for most compared to the existing survey network. When plots were positioned to target two species of conservation concern (crest‐tailed mulgara and dusky hopping mouse), power to detect 30% declines increased by 29% and 31% for these species, respectively, at the cost of reduced power for the remaining species. The effect of varying survey frequency depended on its trade‐off with the number of sites sampled and requires further consideration. Nonetheless, our research suggests that track‐based surveying is an effective and logistically feasible approach to monitoring broad‐scale occupancy trends in desert species with both widespread and restricted distributions. [ABSTRACT FROM AUTHOR]

Sand and dust storms are hazardous to the environment and have a significant role in desertification. Under the influence of climate change and human activities, dust storms and aeolian processes have been common phenomena in the Southern Balkash deserts in Kazakhstan, Central Asia. However, knowledge gaps on spatial and temporal characteristics of dust storms and aeolian process in the Southern Balkash deserts still exist. Therefore, in present study, meteorological observations and numerous cartographic materials were used to identify the powerful sources with the highest frequency of dust storms and aeolian processes in the Southern Balkash deserts. The result showed that the Southern Balkash deserts were covered mainly by transverse parabolic sands (48%), dome dunes (24%), and transverse dome dunes (23%), where the aeolian processes occurred to a significant degree. Significant and strong degrees of aeolian processes occurred in most of the Southern Balkash deserts. The eastern part of the Taukum and the northern part of the Zhamankum and Karakum deserts were prone to aeolian processes to a substantial degree. The Moiynkum, Bestas, Saryesikatyrau, and Taukum deserts had the most frequent storms, occuring, on average, 17 to 43 days/per year. The occurrence of dust storms has been of a stable decreasing trend since the 1990s, except for 2008–2009. Aeolian dust in the Southern Balkash deserts flowed mainly from the western and southwestern to the eastern and northeastern. The results of the present study shed light on the temporal and spatial characteristics of dust storms and aeolian processes in the Southern Balkash deserts. This is of great importance in helping to monitor and predict dust storms and motion patterns of aeolian dust in this region. [ABSTRACT FROM AUTHOR]

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Despite gaining significant cultural and academic currency, penal abolitionism remains unable to radically problematize the punishment of individuals found responsible of exceptionally disturbing acts of criminalized violence. Through an empirical examination of a recent Canadian controversy over penal governance articulated to the transfer of a "monster" to a correctional healing lodge, the article makes legible our difficulties in communicating about appropriate responses to exceptional criminalized incidents which would forgo the use of afflictive sanctions as retaliatory harms. Engaging penal abolitionism empirically, theoretically and normatively, the article notably suggests that the limits of penal abolitionism can be explicated by the fact that its critique is premised on an instrumentalist conception of penalty which neglects the communicational function of punishment. [ABSTRACT FROM AUTHOR]

It is well documented that the recovery of dryland plant communities following wildfire can be variable, and that legacies of fire can have long‐lasting effects on aboveground plant communities. However, our understanding of the degree to which dryland soil seed banks, or the viable seeds in situ, are impacted by fire and their subsequent postfire succession remains extremely poor. To address this important knowledge gap, we used a time‐since‐fire approach to investigate soil seed bank community changes approximately 15 and 30 years after wildfire and to determine the influence of microsites (e.g., shrub vs. interspace) on seed bank composition. We assessed soil seed bank metrics across four North American deserts, including two cold desert sites (Colorado Plateau and Great Basin) and two warm desert sites (Chihuahuan and Sonoran). In greenhouse emergence trials, we found that seed bank characteristics diverged between warm and cold desert sites, such that warm desert sites had seed banks dominated by annual plants while our cold desert sites had seed banks with greater proportions of perennial species, regardless of fire history. In cold desert sites, fire significantly altered seed bank species composition even 30 years after fire. Shrub versus interspace microsites had no observed influence on seed bank composition in any desert. However, seed bank species richness was greater under shrubs in both warm deserts. Non‐native species were present in the seed banks of all deserts and some were particularly abundant in the burned sites. Despite the presence of native species in both burned and unburned seed banks, the presence of non‐native species suggests some degree of vulnerability to future disturbances because fire can create amplifying feedback with many non‐native plants. Our results highlight strong differences in fires' relationship with seed banks for warm and cold desert sites and lend insight into how fire relates to the composition and diversity of the seeds that play a fundamental role in future plant communities. [ABSTRACT FROM AUTHOR]

Vegetation plays a key role in maintaining ecosystem stability, promoting biodiversity conservation, serving as windbreaks, and facilitating sand fixation in deserts. Based on the Moderate Resolution Imaging Spectroradiometer Normalized Difference Vegetation Index (MODIS NDVI) and climate data, a Theil—Sen median trend analysis combined with the Mann—Kendall test and partial correlation and residual analyses were employed to explore spatiotemporal patterns of vegetation dynamics and key drivers in the Badain Jaran and Tengger deserts and Mu Us Sandy Land. Data were collected during the growing season between 2001 and 2020. Further analyses quantified the relative contribution of climate variation and anthropogenic activities to NDVI changes. Results revealed a predominantly increasing trend for average NDVI. The spread of average annual NDVI and growth trends of the vegetation were determined to be influenced by spatial differences. The area with improved vegetation was greater than that of the degraded region. Climate variability and human activities were driving forces controlling vegetation cover changes, and their effects on vegetation dynamics varied by region. The response of vegetation dynamics was stronger for precipitation than temperature, indicating that precipitation was the main climate variable influencing the NDVI changes. The relative role of human activities was responsible for > 70% of the changes, demonstrating that human activities were the main driving factor of the NDVI changes. The implementation of ecological engineering is a key driver of increased vegetation coverage and has improved regional environmental quality. These results enhance our knowledge regarding NDVI change affected by climate variation and human activities and can provide future theoretical guidance for ecological restoration in arid areas. [ABSTRACT FROM AUTHOR]

Shrubs are important factors in the assembly of desert plant and animal communities. By providing shelter and resources to other plants and animals, shrubs can change plant–animal interactions including those with consumers and pollinators. Here, we test the hypothesis that shrubs facilitate the reproduction of other desert plants by influencing pollination and compensation for consumer pressure. We used the known benefactor Larrea tridentata as our focal shrub species and the flowering annual Malacothrix glabrata as a potential protege in the Mojave Desert. We tested the effects of facilitation (shrub microsite), consumer pressure (both artificial folivory and florivory), and pollination (ambient or supplemented) on flower and seed production of the annual M. glabrata. We found that floral production and seed mass were similar between microsites but that pollen was limited under shrubs in the absence of any other manipulation. Plants under shrubs produced more flowers and seeds than in the open when folivory and florivory treatments were applied. Malacothrix glabrata experienced a cost to association with L. tridentata in terms of pollen limitation but plants were better able to compensate for consumer pressure under shrubs through increased flower and seed production when damaged. Therefore, association with shrubs involves a reproductive trade-off between costs to pollination and benefits to compensation for consumer pressure. [ABSTRACT FROM AUTHOR]

Simple Summary: In the first sections of this review, we provide a comprehensive description of the Hedgehog signalling pathway in mammals and the main general models of pathway activation. Subsequently, the review focuses on the oncogenic role played by this pathway in rhabdomyosarcoma and the inhibitors developed to date, as well as the clinical trials available in sarcomas. Finally, we provide a discussion and critical review of the results obtained in the clinical setting and their strong dependency on the type of tumour. In some cases, strong discrepancies between encouraging preclinical data and clinical trial results are clearly evident. Aberrant activation of the Hedgehog (Hh) signalling pathway is known to play an oncogenic role in a wide range of cancers; in the particular case of rhabdomyosarcoma, this pathway has been demonstrated to be an important player for both oncogenesis and cancer progression. In this review, after a brief description of the pathway and the characteristics of its molecular components, we describe, in detail, the main activation mechanisms that have been found in cancer, including ligand-dependent, ligand-independent and non-canonical activation. In this context, the most studied inhibitors, i.e., SMO inhibitors, have shown encouraging results for the treatment of basal cell carcinoma and medulloblastoma, both tumour types often associated with mutations that lead to the activation of the pathway. Conversely, SMO inhibitors have not fulfilled expectations in tumours—among them sarcomas—mostly associated with ligand-dependent Hh pathway activation. Despite the controversy existing regarding the results obtained with SMO inhibitors in these types of tumours, several compounds have been (or are currently being) evaluated in sarcoma patients. Finally, we discuss some of the reasons that could explain why, in some cases, encouraging preclinical data turned into disappointing results in the clinical setting. [ABSTRACT FROM AUTHOR]

This article focuses on justified responses to "immoral" behavior and crimes committed by patients undergoing neuromodulation therapies. Such patients could be held morally responsible in the basic desert sense—the one that serves as a justification of severe practices such as backward‐looking moral outrage, condemnation, and legal punishment—as long as they possess certain compatibilist capabilities that have traditionally served as the quintessence of free will, that is, reasons‐responsiveness; attributability; answerability; the abilities to act in accordance with moral reasons, second‐order volitions, or Deep Self. Recently leading compatibilist neuroethicists added the condition of not feeling alienated from desires motivating a person's action. This article argues against such attempts to determine conditions under which patients undergoing neuromodulation should be subject to negative reactive attitudes and legal punishment. Compatibilism should not be used to justify basic desert moral responsibility and legal punishment. Instead, a new way of thinking about the function of moral responsibility attribution is proposed for patients with neuromodulation. Their compatibilist capabilities should serve as important indicators for determining appropriate, forward‐looking courses of action, such as quarantining and restorative treatment, to ensure the public safety and well‐being of the patients. [ABSTRACT FROM AUTHOR]

Microbially induced calcium carbonate precipitation (MICP) is one widespread approach to soil clay improvement in sustainable biological engineering in the world. The green and efficient approach can also greatly contribute to a series of environmental and ecological challenges. Among them, urea-producing bacteria can be used to induce calcium carbonate precipitation for better soil consolidation. Bacterially generated urease enzymes can decompose the urea to further promote the binding of Ca2+ and CO32-. Therefore, the calcium carbonate precipitation can be expected to apply to desertification combating. However, the urea-producing bacteria can be limited to environmental adaptability and weak function in a harsh desert environment. Many technical bottlenecks are urgent issues for the sand-fixation using calcium carbonate precipitation induced by urea-producing bacteria. It is a high demand to develop native urea-producing bacteria. In the preliminary research, the strain of Sporosarcina pasteurii was identified from the aeolian soils in the Mu Us desert. In this research, the optimal reaction conditions were determined to verify the sand-fixation effect in the desert soil after optimization. A series of single-factor experiments were designed during 0-72 h with the different experimental gradients by pH (7, 8, 9, and 10), bacterial inoculum (1%, 2%, 3%, 4%, and 5%), the ratio of bacterial and cementing solution (25%, 50%, and 75%), and temperature (30, 35, and 40 ℃). The initial urease activity and calcium deposition rate were tested using the response surface method. The optimal reaction factors and conditions were then determined from the six factors (reaction time, pH, bacterial inoculum, the ratio of bacterial and cementing solution, reaction temperature, and initial urease activity). The sand-fixation experiments were carried out on the aeolian soil from the Mu Us desert under optimized conditions. Mineral morphologies and properties were then characterized by the scanning electron microscope (SEM). The thickness and hardness of the soil consolidated layer, soil particle distribution, soil organic matter and calcium carbonate content were measured to calculate the erodibility factor (EF) under soil wind erosion. The results showed that: 1) The main reaction drivers of calcium carbonate precipitation were determined as the reaction temperature, reaction time, pH value, as well as the ratio of bacterial and cementing solution. An optimal combination of conditions was achieved at 34.47 ℃, 71.68 h, pH 7.73, and 74.94% ratio. In this condition, the maximum rate of calcium deposition was 42.33%. 2) The calcium carbonate precipitation was obtained in the polycrystalline phase composition with the cubic, rhombic, spherical, and amorphous under the optimized conditions. Diverse calcium carbonate precipitation was formed on the surface of sand grains, or embedded in the sand grains. 3) Sand-fixation by induced calcium carbonate precipitation was significantly enhanced after optimization. The number of sand particles increased significantly (P<0.05), and the thickness and hardness of the soil consolidated layer increased by 5 and 10 times, respectively. The contents of organic matter and calcium carbonate increased significantly, whereas, the wind EF decreased from 0.94 to 0.66. Therefore, the urea-producing bacteria-induced calcium carbonate precipitation can serve as the new effective and favorable sand fixation for desertification combating in the future. It is still necessary to develop the distribution of simultaneous ecological restoration, in order to gradually promote this new technology in large-scale field experiments. Consequently, in the field application, the sand fixation effect can be enhanced to further determine the application time and water under suitable conditions and the soil compaction will be avoided by appropriately breaking. [ABSTRACT FROM AUTHOR]

Premise: Tree growth is a fundamental biological process that is essential to ecosystem functioning and water and element cycling. Climate exerts a major impact on tree growth, with tree species often requiring a unique set of conditions to initiate and maintain growth throughout the growing season. Still, little is known about the specific climatic factors that enable tree growth in savannah and desert tree species. Among the global tree species, Acacia tortilis occupies one of the largest distribution ranges (crossing 6500 km and 54 latitudes), spanning large parts of Africa and into the Middle East and Asia. Methods: Here we collected climate data and monitored Acacia tortilis tree growth (continuous measurements of stem circumference) in its southern and northern range edges in South Africa (SA) and Israel (IL), respectively, to elucidate whether the growth–climate interactions were similar in both edges. Results: Growth occurred during the summer (between December and March) in SA and in IL during early summer and autumn (April–June and October–November, respectively). Surprisingly, annual growth was 40% higher in IL than in SA. Within the wide distribution range of Acacia tortilis, our statistical model showed that climatic drivers of tree growth differed between the two sites. Conclusions: High temperatures facilitated growth at the hot and arid IL site, while high humidity permitted growth at the more humid SA site. Our results confer an additional understanding of tree growth adaptation to extreme conditions in Acacia's world range edges, a major point of interest with ongoing climate change. [ABSTRACT FROM AUTHOR]

Intermittent and ephemeral streams in dryland environments support diverse assemblages of aquatic and terrestrial life. Understanding when and where water flows provide insights into the availability of water, its response to external controlling factors, and potential sensitivity to climate change and a host of human activities. Knowledge regarding the timing of drying/wetting cycles can also be useful to map critical habitats for species and ecosystems that rely on these temporary water sources. However, identifying the locations and monitoring the timing of streamflow and channel sediment moisture remains a challenging endeavor. In this paper, we analyzed daily conductivity from 37 sensors distributed along 10 streams across an arid mountain front in Arizona (United States) to assess spatiotemporal patterns in flow permanence, defined as the timing and extent of water in streams. Conductivity sensors provide information on surface flow and sediment moisture, supporting a stream classification based on seasonal flow dynamics. Our results provide insight into flow responses to seasonal rainfall, highlighting stream reaches very reactive to rainfall versus those demonstrating more stable streamflow. The strength of stream responses to precipitation are explored in the context of surficial geology. In summary, conductivity data can be used to map potential stream habitat for water‐dependent species in both space and time, while also providing the basis upon which sensitivity to ongoing climate change can be evaluated. [ABSTRACT FROM AUTHOR]

Environmental DNA is a powerful tool for monitoring biodiversity. Although environmental DNA surveys have successfully been implemented in various environments, protocol choice has been shown to affect results and inferences. Thus far, few method comparison studies for soil have been undertaken. Here, we optimized the workflow for soil metabarcoding through a comparative study encompassing variation in sampling strategy (individual and combined samples), DNA extraction (PowerSoil®, NucleoSpin® Soil, PowerSoil® + phosphate buffer and NucleoSpin® Soil + phosphate buffer) and library preparation (one-step and two-step quantitative polymerase chain reaction methods). Using a partial 18S rRNA marker, a total of 309 eukaryotic taxa across 21 phyla were identified from Antarctic soil from one site in the Larsemann Hills. Our optimized workflow was effective with no notable reduction in data quality for a considerable increase in time and cost efficiency. The NucleoSpin® Soil + phosphate buffer was the best-performing extraction method. Compared to similar studies in other regions, we obtained low taxonomic coverage, perhaps because of the paucity of Antarctic terrestrial organisms in genetic reference databases. Our findings provide useful methodological insights for maximizing efficiency in soil metabarcoding studies in Antarctica and other low-biomass environments. [ABSTRACT FROM AUTHOR]

IntroductionSoil water availability is a key factor in the growth of trees. In arid deserts, tree growth is limited by very dry soil and atmosphere conditions. Acacia tree species are distributed in the most arid deserts of the globe, therefore they are well adapted to heat and long droughts. Understanding why some plants do better than others in some environments is a key question in plant science.MethodsHere we conducted a greenhouse experiment to continuously and simultaneously track the whole-plant water-balance of two desert Acacia species, in order to unravel their physiological responses to low water availability.ResultsWe found that even under volumetric water content (VWC) of 5-9% in the soil, both species maintained 25% of the control plants, with a peak of canopy activity at noon. Moreover, plants exposed to the low water availability treatment continued growing in this period. A. tortilis applied a more opportunistic strategy than A. raddiana, and showed stomatal responses at a lower VWC (9.8% vs. 13.1%, t4= -4.23, p = 0.006), 2.2-fold higher growth, and faster recovery from drought stress.DiscussionAlthough the experiment was done in milder VPD (~3 kPa) compared to the natural conditions in the field (~5 kPa), the different physiological responses to drought between the two species might explain their different topographic distributions. A. tortilis is more abundant in elevated locations with larger fluctuations in water availability while A. raddiana is more abundant in the main channels with higher and less fluctuating water availability. This work shows a unique and non-trivial water-spending strategy in two Acacia species adapted to hyper-arid conditions.

Abstract Positive associations between animals and foundational shrub species are frequent in desert ecosystems for shelter, resources, refuge, and other key ecological processes. Herein, we tested the impact of the density of the shrub species Ephedra californica on the presence and habitat use of the federally endangered lizard species, Gambelia sila. To do this, we used a 3‐year radio telemetry dataset and satellite‐based counts of shrub density across sites at the Carrizo Plain National Monument in San Luis Obispo County, CA. The effect of shrub density on lizard presence was contrasted with previous shrub cover analyses to determine whether measures of shrub density were superior to shrub cover in predicting lizard presence. Increasing shrub density increased lizard presence. As shrub density increased, lizards were located more frequently “above ground” versus “below ground” in burrows. Male lizards had significantly larger home ranges than females, but both sexes were similarly associated with increasing shrub densities. Shrub density and shrub cover models did not significantly differ in their prediction of lizard presence. These findings suggest that both habitat measures are effective analogs and that ecologically, both cover and the density of foundation shrub species are key factors for some desert lizards.

The spatial distribution of tumor infiltrating lymphocytes (TILs) defines several histologically and clinically distinct immune subtypes—desert (no TILs), excluded (TILs in stroma), and inflamed (TILs in tumor parenchyma). To date, robust classification of immune subtypes still requires deeper experimental evidence across various cancer types. Here, we aimed to investigate, define, and validate the immune subtypes in melanoma by coupling transcriptional and histological assessments of the lymphocyte distribution in tumor parenchyma and stroma. We used the transcriptomic data from The Cancer Genome Atlas melanoma dataset to screen for the desert, excluded, and inflamed immune subtypes. We defined subtype-specific genes and used them to construct a subtype assignment algorithm. We validated the two-step algorithm in the qPCR data of real-world melanoma tumors with histologically defined immune subtypes. The accuracy of a classifier encompassing expression data of seven genes (immune response-related: CD2, CD53, IRF1, and CD8B; and stroma-related: COL5A2, TNFAIP6, and INHBA) in a validation cohort reached 79%. Our findings suggest that melanoma tumors can be classified into transcriptionally and histologically distinct desert, excluded, and inflamed subtypes. Gene expression-based algorithms can assist physicians and pathologists as biomarkers in the rapid assessment of a tumor immune microenvironment while serving as a tool for clinical decision making.

Shrubland is an important type of vegetation in the semi-arid region of the western Loess Plateau, and it is of great value to the maintenance of biodiversity and soil and water conservation. Equally, there may be significant differences in the level of diversity and the community assembly patterns across different types of shrublands (desert, alpine, and secondary shrublands). This study aimed to reveal the diversity and the community assembly patterns of different types of shrublands and the environmental explanations for these by using a taxonomic and phylogenetic analysis approach, as well as by considering soil and climate factors. The diversity level of the desert shrublands was low, and the habitats of the three types of shrubland were significantly different. Precipitation may be the main environmental factor driving the variation in and diversity of these types of shrubland. All three types of shrubland were strongly affected by environmental filtering and competitive exclusion, and their community assembly patterns were similar.

Salt stress is a key environmental factor that has adverse effects on plant growth and development. High salinity induces a series of structural and functional changes in the morphological and anatomical features. The physiological and biochemical changes in K. foliatum in response to salt stress in natural environments are still unclear. Based on this, this study compared and analyzed the differences in the physiological and biochemical indicators between the leaf and root tissues in high-salt and low-salt habitats, selecting K. foliatum as the research object. The results showed that the chlorophyll contents in the leaves of K. foliatum decreased in the high-salt habitat, while the thicknesses of the upper and lower epidermises, as well as the thicknesses of the palisade tissue, significantly increased. The high-salt environment led to decreases in the N and P contents in the leaves and root tissues of K. foliatum, resulting in changes in the stoichiometric ratio of elements. The concentrations of C, N, and P in the roots of K. foliatum were lower than those in the leaves. The accumulation of Na+ in the K. foliatum roots was greater than that in the leaves, and the roots could promote the transport of sodium ions to the leaves. The contents of starch and soluble sugar in the leaves showed higher proportions in the high-salt habitat than in the low-salt habitat, while the changes in the roots and leaves were the opposite. As the salt content increased, the proline contents in the leaves and roots of K. foliatum significantly increased, and the proline contents in the roots of K. foliatum were lower than those in the leaves. The leaves and roots exhibited higher levels of peroxidase and superoxide enzymes in the high-salinity habitat than in the low-salinity habitat. The superoxide dismutase (SOD) activity of the K. foliatum leaves and catalase (CAT) activity of the roots were the “central traits” in the high-salt habitat. In the low-salt habitat, the leaf malondialdehyde (MDA) and root C/N were the central traits of the leaves and roots, indicating that K. foliatum adapts to changes in salt environments in different ways.

This paper is devoted to the analysis of air temperature and humidity changes during the two solar eclipses of 26 December 2019 and 21 June 2020 in Saudi Arabia based on data we collected from two different sites. We highlight the complexity of humidity’s response to a solar eclipse, which is quite different from temperature’s response. During the December event, the Sun rose already partially eclipsed, while for the June eclipse, it was only partial at Riyadh. This difference apparently affected the observed response on the recorded variables: temperature, relative humidity (RH), and vapor pressure (VP) in the two events. Changes in these variables went unnoticed for the first eclipse since they were within the natural variability of the day; yet for the other, they showed evident alterations in the slopes of the major parameters, which we analyze and discuss. A decrease in temperature of 3.2 °C was detected in Riyadh. However, RH and VP showed an oscillation that we explain taking into account a similar effect reported in other eclipses. We measured a time lag of about 15 min from the eclipse central phase in the city. Related fluctuations and dynamics from the computed rates of the temporal variation of temperature and RH are scrutinized. Furthermore, an overdue significant review of terrestrial atmospheric parameters is also offered in the context of the eclipse meteorology, particularly related to desert atmospheres. We also try to identify the influence of solar eclipses in similar environments doing a broad inter-comparison with other observations of these variables in the Near East, northern Africa, and in the United States. These inter-comparisons reveal how complex and dissimilar the response of the lower atmosphere to a solar eclipse can be within a desert environment and other similar environments.

Plant height (PH) plays a crucial role in determining per-plant growth and biomass production. Various characteristics of PH, along with the formulation of mathematical growth models, can provide a theoretical yield or biomass production based on water quality, fruit quality, and yields. The aim of this study was to investigate the relationship between PH and biomass per-plant production of two fodder crops (Cluster bean and Sesbania) under different water quality irrigation parameters in the Thar desert of Pakistan. Universal models of PH were established in which growing degree days (GDDs) and different water quality irrigation techniques have been applied as independent variables to calculate the maximum plant height of both of these crops. For this purpose, the logistic growth model, Gaussian growth model, modified Gaussian growth model, and Cubic polynomial growth model were used. Furthermore, universal biomass per plant production models have been developed for both crops, between biomass per plant, GDDs, and PH. However, among all these developed models, the modified Gaussian and Cubic polynomial growth models produced the best results. The Cubic polynomial model has meaningless parameters that make the model not very accurate, so the modified Gaussian growth model is the best among all models. Furthermore, the relationship between biomass per plant and different water qualities was established using Michaelis–Menten equations for both crops. It was observed that an increase in salt concentration within the water quality led to a decline in biomass per plant, indicating a negative linear relationship between these factors. The growth of Cluster bean and Sesbania ceased when the electrical conductivity (EC) reached or exceeded 12.34 ds/m and 11.51 ds/m, respectively. Furthermore, the results show that Cluster bean and Sesbania have the maximum plant height under brackish water irrigation when the GDD is at 1500 °C, while in freshwater irrigation, the maximum plant height of Sesbania and Cluster bean was observed when the GDD is at 1444 °C and 1600 °C. It was concluded that these developed mathematical models can provide crucial insights for enhancing production in desert conditions by improving water use efficiency across diverse irrigation water qualities.

The Negev desert, the southern half of Israel, is an arid-to-hyper-arid region. Despite that, some 13,000 ancient sites have been recorded here to date, and many were excavated. One characteristic of the Negev (as well as of other deserts) is the abundance of prehistoric and early historic cult sites, dated ca. 8000–2000 BCE. Another is the many ancient roads. The roads, the main types of cult sites and the connection between them are described and discussed in the following sections.

Drought and climate change have decreased water availability for agriculture, especially in the desert of southwestern USA. Efficiency enhancements in irrigation management aimed at conserving water are key to adjust to limits in water supply, improve profitability and sustainability of alfalfa production in arid and semiarid areas. This study intended to conduct a field-scale analysis to develop yield and ET estimation tools for the effective use of irrigation water in a desert alfalfa production system. Extensive data collection and trials were carried out over three years in nine fully irrigated commercial alfalfa fields in the low deserts of California. The seasonal crop water consumption measured using the residual of energy balance method varied from 1381 mm to 1596 mm across the experimental sites and crop seasons. Variable seasonal dry mater (DM) yields ranged from 23.01 Mg ha−1 to 29.90 Mg ha−1. The results indicated that the first five cuttings each year were the most productive cuttings with a mean DM value ranged between 3.29 (cut 1) and 4.21 (cut 4) Mg ha−1 but declined in later cuttings. An average annual water productivity (WP) value of 17.0 kg ha−1 mm−1 was determined across the sites varying from 15.5 to 18.9 kg ha−1 mm−1. The findings suggested that one may lose up to 1.44 Mg ha−1 alfalfa yields with moderate summer deficit irrigation strategies, using 40% less water applied than full irrigation practices over the summer period of July–September. A more severe summer water deficit, with no irrigation event over the summer period of July–September may result in a potential water savings of 0.234–0.246 (ha·m) ha−1 and 19–21% seasonal yield losses in the desert environment. This study describes the seasonal yield pattern, the crop water use-production function, and the crop coefficient values for various harvest cycles over the crop season. These tools may assist farmers to quantify water savings and estimate yield losses for more accurate and effective irrigation management strategies to meet water conservation objectives and for the resiliency of alfalfa production in the desert region.

A lone traveler has only their mother's writings and stories to keep them company.

At around 7:30pm on April 13, 2017 the US government dropped the Massive Ordnance Air Blast (MOAB) bomb near the Moman Dara Village in the Asadkhel area in the Achin district of Nagarhar province in eastern Afghanistan. Nicknamed the "Mother of All Bombs" the weapon is the largest non-nuclear weapon in the US arsenal, with a blast radius, meaning the area in which serious effects on people and structures can be felt, of a mile. While the MOAB was the largest weapon released, it was but one of 4,361 air weapons that targeted Afghanistan during 2017, according to US Air Forces Central Command declassified airpower summaries. At 7:30am on April 13, 2018, the anniversary of this event, I walked a path equivalent to the blast radius of MOAB on land in Arizona. This walk memorialized the civilians killed, the villages terrorized, the populations forced to migrate, and the lands scarred as a result of the endless wars being carried out in the name of protecting US citizens.

El presente trabajo ofrece una interpretación hermenéutica del espectáculo Limbo, de la artista mexicana Gabriela Muñoz, también conocida como “Chula the clown”, a partir de los conceptos desierto y exilio, presentes en este ejercicio escénico, así como en el pensamiento de María Zambrano, donde se muestran como un problema filosófico, y en la obra del investigador Ignacio Izuzquiza. Exilio y desierto aparecen también en Esperando a Godot de Samuel Beckett, obra que se revela como influencia del trabajo de Muñoz y con la que comparte algunos signos poéticos. El texto, asimismo, retoma los apuntes de la investigadora Melissa Lima Caminha, principalmente la noción de deconstrucción del clown femenino moderno y la categoría de monstruosidad para hablar de quienes han sido expulsados o expulsadas del grupo social por ser considerados diferentes, y con lo cual viven, precisamente, en los linderos del exilio. En Muñoz, como sucede con la tradición clown, esta figura cómica se muestra como símbolo de lo excluido, lo deforme, lo anormal e, incluso, de lo despreciable. A partir de estas claves, la artista muestra el limbo como un estado emocional donde se diluyen las fronteras del tiempo y el espacio, en un ambiente que se mueve entre la desolación y la comicidad. This paper offers a hermeneutical approach to Limbo, a clown spectacle by Mexican artist Gabriela Muñoz, known as “Chula the clown”, from the concepts of desert and exile, both present in this perfor-mance, as in Maria Zambrano’s work, as a philosophical problem, and in researcher Ignacio Izuzquiza’s reflection. Exile and desert are at work also in Samuel Beckett’s play Waiting for Godot, influential on Muñoz per-formance, as it is shown by some poetic signs. From researcher Melissa Lima Caminha, our paper works deconstructivity on the modern feminine clown notion and monstrosity category to talk about people whom have been expelled from their social community as they are considered different, living then in the borders of exile. In Muñoz, as in clown tradition, this comic figure is shown as a symbol of the ones excluded, deformed, abnormal and, even, despicable. From these key issues, the artist presents limbo as an emotional state where frontiers of time and space are diluted, in an environment moving through desolation and comicality

In arid and semi-arid regions, efficient utilization of available water necessitates the adaptation of appropriate water management practices. One such approach is through soil conditioners like polymer hydrogels. The application of polymer hydrogels aids efficient management of water in agricultural production by increasing water holding capacity and improving water conservation of sandy soils. This has led to practical applications of these materials particularly in arid regions and countries, where water is the limiting factor for plant production. Therefore, the ultimate objective of this study was to address the impacts of different polymer hydrogels such as potassium polyacrylate (PH1), starch-acrylonitrile (PH2), starch-acrylic-acid (PH3) and polyacrylic acid (PH4) on the moisture capacity of sandy soils from sand dune. The sandy soils contained >95% sand. Maximum rate of water absorption of polymers (PH1, PH2, PH3 and PH4) were 174, 38.75, 21.7 and 201.1 times their weight respectively. Four polymer hydrogels with three treatments (0.25:0.75, 0.5:0.5 and 0.75:0.25; v/v) were used in the experiment with four replication. With respect to the untreated soil, addition of polymer hydrogels increased significantly full moisture capacity (FMC) and smallest moisture capacity (SMC) for for all polymer: sand mixtures. PH1 recorded highest FMC and SMC than all four polymers. The results suggest that addition of a potassium polyacrylate to sandy soils is more effective polymer hydrogel at increasing moisture capacity in sandy soils.

It is important to know about the deserts of Iran because the geographical and climatic conditions of the desert have never been expanding by themselves. What expands deserts is the relationship that desert areas have with their surrounding environment. Climate change during the last few decades has caused climatic hazards in desert areas to cause a lot of human and financial losses. The purpose of this research is the spatial planning of climatic hazards in order to reduce their damages in desert areas. This research is descriptive-analytical in terms of applied method. At first, the most important climate hazards in desert areas were identified. Then, using the opinion of experts and interviewing them, the most important criteria and strategies to reduce the damages of climate hazards in desert areas were identified. The results showed that drought, increase in temperature intensity, heavy and short-term rainfall, frost, dust storms, and floods were identified as the most important climatic hazards during the past few years. In this research, cost-benefit, people's participation, technological and scientific tools available, political and social pressures, appropriateness and compatibility with the environment, traditional management and indigenous knowledge, government oil revenues, temporary managements, problems related to innovation and changing methods, The convenience of government administrative systems is a factor, and time, the beauty of the landscape, expert human resources, and emergency issues caused by climate hazards are considered as handicaps. The results show that the approval of a new and comprehensive law related to climate risks is the most important

Introduction: Biological soil crusts including cyanobacteria, fungi, bacteria, actinomycetes, algae, viruses, mosses, lichens, and plants are formed on the soil surface. Cyanobacteria are key microorganisms in the formation of the biological soil crust, especially in arid and desert areas. Cyanobacteria increase carbon and nitrogen content in soil via increasing colony formation and Exopolysaccharide (EPS) production and play an important role to strengthen soil structure especially in poor soil and prevent it from eroding.Materials and Methods: In the present study, three cyanobacteria with the highest secreted carbohydrate production were selected among 19 isolates of different provinces’ soil. The amount of carbohydrate production of the selected strains was determined by using the phenolic sulfuric acid method. Then, three selected strains, with the highest amount of secreted carbohydrate were inoculated to the pot filling with poor soils. After 7 weeks of cyanobacterial inoculation, some physical and chemical alterations of the soil were measured. Furthermore, the rate of formation of the biological soil crust and the adhesiveness of the soil particles were microscopically investigated.Results: The carbohydrate content was 86.66 µg/ml for Anabaena sphaerica, 55. 91 µg/ml for Geitlerinema.sp, and 64.19 µg/ml, for Nostoc pruniforme. The results of the study also show that these three strains are capable of forming biological soil crust on the soil surface.Discussion and Conclusion: Anabaena sphaerica, due to its high growth rate, more biomass production, and more secreted carbohydrates increased soil nitrogen and carbon content, as well as better formation of biological soil crust was selected for further investigation. This strain improved some soil texture characteristics and probably it can have a positive effect on soil fertility.

Abstract Background Medicinal plants have been successfully used as an alternative source of drugs for the treatment of microbial diseases. Finding a novel treatment for malaria is still challenging, and various extracts from different wild desert plants have been reported to have multiple medicinal uses for human public health, this study evaluated the antimalarial efficacy of several Egyptian plant extracts. Methods We assessed the cytotoxic potential of 13 plant extracts and their abilities to inhibit the in vitro growth of Plasmodium falciparum (3D7), and to treat infection with non-lethal Plasmodium yoelii 17XNL in an in vivo malaria model in BALB/c mice. Results In vitro screening identified four promising candidates, Trichodesma africanum, Artemisia judaica, Cleome droserifolia, and Vachellia tortilis, with weak-to-moderate activity against P. falciparum erythrocytic blood stages with mean half-maximal inhibitory concentration 50 (IC50) of 11.7 μg/ml, 20.0 μg/ml, 32.1 μg/ml, and 40.0 μg/ml, respectively. Their selectivity index values were 35.2, 15.8, 11.5, and 13.8, respectively. Among these four candidates, T. africanum crude extract exhibited the highest parasite suppression in a murine malaria model against P. yoelii. Conclusion Our study identified novel natural antimalarial agents of plant origin that have potential for development into therapeutics for treating malaria.

Dung beetles can influence seedling emergence and survival. However, the direction and magnitude of this effect will depend on the functional traits of the dung beetle community and on the prevailing environmental conditions. We studied the role of dung beetles in seed dispersal of Prosopis flexuosa DC. in an arid environment. We conducted an experimental study to assess how different dung beetle species differ in their effectiveness as secondary seed dispersers. To evaluate this question, we selected four species belonging to three functional groups: lifters, tunnelers, and rollers. Dung beetles removed 0.7%-7.5% of the seeds embedded in cow dung. The net effect of beetles on seedling emergence and survival varied markedly among species: Malagoniella puncticollis (roller) had neutral effects on seedling emergence and positive in their survival. Sulcophanaeus imperator, Digitonthophagus gazella (tunneler) and Eucranium arachnoides (lifters) species had positive effect on seedling emergence. However, the effect of S. imperator on seedling survival was negative, and those of D. gazella and E. arachnoides, neutral. Our results indicate that although dung beetles remove few seeds of P. flexuosa, their main role consisted in producing changes in micro-environmental conditions for the seeds that remained in the dung pile. Photos: Luciana Quiroga (A), Diego N. Mirás (B and C), Belén Maldonado (D)

The west coast of the Arabian Peninsula borders the Red Sea, a water body which maintains high average temperatures and increased salinity compared to other seas or oceans. This geography has many resources which could be used to support algal biotechnology efforts in bio-resource circularity. However, summer conditions in this region may exceed the temperature tolerance of most currently cultivated microalgae. The Cyanidiophyceae are a class of polyextremophilic red algae that natively inhabit acidic hot springs. C. merolae 10D has recently emerged as an interesting model organism capable of high-cell density cultivation on pure CO2 with optimal growth at elevated temperatures and acidic pH. C. merolae biomass has an interesting macromolecular composition, is protein rich, and contains valuable bio-products like heat-stable phycocyanin, carotenoids, β-glucan, and starch. Here, photobioreactors were used to model C. merolae 10D growth performance in simulated environmental conditions of the mid-Red Sea coast across four seasons, it was then grown at various scales outdoors in Thuwal, Saudi Arabia during the Summer of 2022. We show that C. merolae 10D is amenable to cultivation with industrial-grade nutrient and CO2 inputs outdoors in this location and that its biomass is relatively constant in biochemical composition across culture conditions. We also show the adaptation of C. merolae 10D to high salinity levels of those found in Red Sea waters and conducted further modeled cultivations in nutrient enriched local sea water. It was determined that salt-water adapted C. merolae 10D could be cultivated with reduced nutrient inputs in local conditions. The results presented here indicate this may be a promising alternative species for algal bioprocesses in outdoor conditions in extreme coastal desert summer environments.

Over the last 30 years, the description of microbial diversity has been mainly based on culture-independent approaches (metabarcoding and metagenomics) allowing an in-depth analysis of microbial diversity that no other approach allows. Bearing in mind that culture-dependent approaches cannot replace culture-independent approaches, we have improved an original method for isolating strains consisting of “culturing” grains of sand directly on Petri dishes (grain-by-grain method). This method allowed to cultivate up to 10% of the bacteria counted on the surface of grains of the three sites studied in the Great Western Erg in Algeria (Timoudi, Béni Abbès, and Taghit), knowing that on average about 10 bacterial cells colonize each grain. The diversity of culturable bacteria (collection of 290 strains) predicted by 16S rRNA gene sequencing revealed that Arthrobacter subterraneus, Arthrobacter tecti, Pseudarthrobacter phenanthrenivorans, Pseudarthrobacter psychrotolerans, and Massilia agri are the dominant species. The comparison of the culture-dependent and -independent (16S rRNA gene metabarcoding) approaches at the Timoudi site revealed 18 bacterial genera common to both approaches with a relative overestimation of the genera Arthrobacter/Pseudarthrobacter and Kocuria, and a relative underestimation of the genera Blastococcus and Domibacillus by the bacterial culturing approach. The bacterial isolates will allow further study on the mechanisms of tolerance to desiccation, especially in Pseudomonadota (Proteobacteria).

Abstract Estimating key state variables such as abundance, survival, and recruitment of wild populations, and their interaction with local conditions such as precipitation, is essential for state‐dependent decision making and management. Estimation of state variables remains challenging, especially in species such as mountain ungulates inhabiting rugged and remote terrains. Camera traps present a technological advance that can mitigate some of the challenges in state estimation and can be used to enhance existing methods. Here, we combined camera traps, individual markings, and GPS tracking to estimate abundance and survival for the threatened Nubian ibex (Capra nubiana) population of the Judean Desert, Israel. Since precipitation is a key determinant for recruitment in desert ungulates, we complemented our estimates with kid‐female ratios and regional precipitation records. Between 2016 and 2019, we individually marked 48 ibex of which 38 were also fitted with GPS collars within the Judean Desert. We performed 6 days of camera‐trap surveys each year to estimate abundance for the north Judean Desert population using mark‐resight in a robust‐design framework. Weight‐averaged abundance estimates for 2017–2019, respectively, were as follows: N ¯ ˆ = 267 (95% CI = 117–418, SE = 51.27), 201 (95% CI = 115–288, SE = 36.85), and 226 (95% CI = 154–299, SE = 36.94) for females, and N ¯ ˆ = 291 (95% CI = 154–299, SE = 36.94), 160 (95% CI = 108–212, SE = 25.19), and 283 (95% CI = 181–384, SE = 29.76) for males. By augmenting data from telemetry with camera traps, we estimated survival via known fates for the entire Judean Desert (north, mid, and south populations). Weight‐averaged survival estimates for 2016–2019, respectively, were: S ¯ ˆ = 0.99 (95% CI = 0.97–1.00, SE = 0.012), 0.90 (95% CI = 0.24–0.99, SE = 0.153), 0.87 (95% CI = 0.62–0.97, SE = 0.081), and 0.88 (95% CI = 0.69–0.96, SE = 0.062) for females, and S ¯ ˆ = 0.77 (95% CI = 0.26–0.97, SE = 0.203), 0.64 (95% CI = 0.33–0.86, SE = 0.151), 0.85 (95% CI = 0.60–0.96, SE = 0.087), and 0.88 (95% CI = 0.69–0.96, SE = 0.062) for males. The interannual trends of abundance and survival estimates corresponded with observed kid‐female ratios and the regional precipitation records, reflecting a population decline following 2017's drought and an increase following the increased precipitation in 2018. Our findings substantiate the efficacy of using camera traps to estimate Nubian ibex's key state variables, as well as detecting population trends driven by environmental conditions. Despite being costly, the capacity of statistically‐robust methods to estimate key state variables is indispensable, and camera traps make similar methods increasingly more feasible in remote and inaccessible populations.