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In this study, prominent dust source areas are identified along with their plume extent using high temporal frequency satellite observations. Hourly dust plume observations of the Dust Belt from geostationary‐orbit satellites are analyzed for the 2017‐12–2022‐11 period. To identify dust source areas and their extents, we back‐track plumes to their source, assessing source areas in terms of emission frequency, contribution, and plume extent patterns. This method advances over traditional source allocation techniques that rely on polar‐orbiting satellites based on a few daily passes and meteorological wind fields for backtracking. Our findings indicate that Boreal summer is the most intense season for most sources, except in the Southern Sahara, which experiences winterly winds. Our analysis also reveals significant contributions from regions within the Sahara that experience expansive but infrequent dust storms, highlighting the importance of considering both frequency and magnitude in understanding dust emissions. Plain Language Summary: This study focuses on the role of mineral dust, a significant climate constituent originating mainly from arid regions. Identifying where dust comes from and where it goes is essential for understanding how it affects the climate. To do so, we employ high temporal frequency satellite data to backtrack dust plumes to their sources, revealing key dust‐emitting regions and their seasonal variations. We also quantify each source area's frequency and magnitude of emissions and the spatial distribution of emanating dust plumes. Our findings show that summer is the peak season for most areas, except for the strongest dust sources, located in Southern Sahara, which peak in winter driven by seasonal winds. Additionally, some Saharan source areas exhibit severe storms but have been under‐emphasized because they were measured by the frequency of their storms. Key Points: High‐temporal‐resolution images from geostationary‐orbit satellites enable precise back‐tracking of dust source areasDust source areas are analyzed in terms of their emission frequency, contribution to the regional atmosphere, and corresponding plume extentSummer is the peak dust emission season for most sources in West Asia and Sahara and ephemeral lake beds are active during the dry season [ABSTRACT FROM AUTHOR]

A distinct coal break occurs widely in the late Early Jurassic in Central Asia, the cause of which, however, is still debated largely due to the uncertainty of its age constraint. In the Junggar Basin of northwestern China, this coal break coincides with the Sangonghe Formation, which is well exposed along the basin margins, and is mainly composed of lacustrine deposits rich in a variety of fossils, including plants, pollens and spores, bivalves, clam shrimps, insects and some vertebrates. Here we name them as the Sangonghe biota and review their biostratigraphic framework. The Sangonghe biota constrains the Sangonghe Formation to the late Pliensbachian to the early Aalenian. Abundant thermophilous plants and Classopollis, together with frequent occurrences of red beds and carbonate nodules in the middle part of the Sangonghe Formation, are indicative of an arid climate in Central Asia at that time. This arid interlude should be responsible for the coal break, which may be related to the global warming in the early Toarcian. However, more precise dating evidence is needed to substantiate this. [ABSTRACT FROM AUTHOR]

Landscape productivity and resource dispersion are key drivers of the movement patterns of many species. In less productive environments, home ranges are generally larger as individuals travel further to access resources. The greater bilby (Macrotis lagotis) has been reintroduced to several feral predator exclosures to reduce their extinction risk. Understanding how landscape productivity and resource dispersion influence bilby space use is critical to enable effective management of populations in exclosures. At two exclosures, we tested three hypotheses: 1. Bilbies would preferentially utilize habitats with sandy substrates (<20% clay content), as they are suitable for digging burrows and foraging pits; 2. Home ranges would be larger at the arid site compared to the semi‐arid site due to lower productivity and patchier distribution of preferred habitats; and 3. Bilbies would travel further each night at the arid site to access preferred habitats. Rainfall was used as an indicator of productivity, and dispersion of preferred habitats as an indicator of resource dispersion. The study was undertaken during average rainfall conditions and under similar bilby population densities at both sites. GPS loggers recorded home ranges and movements of 10 bilbies at the arid site, and 11 bilbies at the semi‐arid site. Seventeen of the 21 bilbies preferentially utilized habitats with sandy substrates, which were less abundant at the arid site. There were no significant differences in home range size or nightly movements between the sites for either sex. We suggest the average rainfall conditions at both sites, and the dietary flexibility of bilbies, supported the maintenance of relatively small and stable home ranges (particularly for females). The effects of landscape productivity and resource dispersion on bilby space use are more likely to be evident during extended periods of below average rainfall. Bilby home range studies during low rainfall conditions (e.g. drought) are required for the effective, long‐term management of exclosure populations. [ABSTRACT FROM AUTHOR]

Drylands are characterized by high spatial variability in resource availability due to sporadic rainfall, topography of the landscape and important effects of animals. Resource availability gradients may trigger patterns in decomposer population abundances and activity, which could affect ecosystem functions such as decomposition. Here, we examined the influence of resource availability gradients on the importance of termites in the decomposition of wood and grass litter. We placed wood blocks and grass litter baits in bags accessible and inaccessible to termites across wood and grass resource gradients as determined by the presence or absence of a top mammalian predator and across topographic gradients during a 9‐month period in arid Australia. We hypothesized that grass‐eating termite activity would track grass abundance and wood‐eating termite activity would track wood abundance. Termites were the predominant decomposition agent at these sites. Termites contributed to 99.5% of wood decomposition and 83.9% of grass decomposition during our study period. For wood, the termite effect was spatially variable and increased with habitat wood availability, which was greatest on dunes and where top predators were absent. However, the contribution of termites to grass litter decomposition did not track grass availability or termite abundance. The highest effects of termites on grass decomposition rates were found in habitats where the absence of top predators led to low grass availability. Our findings highlight how spatial variability in resources in addition to other factors that we do not document but are known to be influenced by the presence of top predators, such as insectivore predation rates, across the landscape could affect ecosystem functions such as decomposition. [ABSTRACT FROM AUTHOR]

Key message: The yield of epicuticular waxes of Bulnesia retama was increased mainly by water stress, and marginally by UV-B. Natural populations from the most stressful ecoregions showed higher productivity and plasticity. Bulnesia retama is a tree/shrub endemic to the arid and semi-arid zones of South America. This species produces outer stem waxes that can be used in industry, and has been exploited in the past degrading natural populations. Considering the need to diversify marginal dryland economies by making sustainable use of local resources, we aimed to study the productivity of outer stem waxes of natural populations of B. retama from three eco-regions with different environmental stress (rainfall and altitude). We studied the wax productivity of the three populations in response to water stress and UV-B. We conducted two pot experiments with seedlings propagated from seeds of the different environmental backgrounds. We regulated water availability by differential irrigation and manipulated UV-B using selective absorbance filters. We collected stem waxes by the traditional method of brushing dry stems. We found that water stress was the main promoter of stem wax production in this species, while the effect of UV-B was marginal, and was only detected in combination with water stress. Seedlings from the most stressful eco-regions showed the highest stem wax productivity and were the most plastic to variations in environmental conditions. Environmental stress, particularly water stress, was the determining factor in the outer stem wax yield of this species, and in the productive potential of different natural populations, which could be related to ecotypes with different wax yield potential. This knowledge can be used for exploiting this resource sustainably, to select ecotypes for cultivation, and to develop productive varieties through classical breeding. [ABSTRACT FROM AUTHOR]

Seasonal and regional variations in biochemical and physiological parameters of Artemisia campestris (L.) were investigated. The quantification of proline by the formation of a coloured complex was done by coupling proline with ninhydrin. The determination of soluble sugars and the extraction of chlorophyll from the leaves were carried out. The seasonal average leaf proline concentration of plants from the arid region was higher than that from the semi-arid region. The more the seasonal temperature increases, the greater the concentration of proline, as with the concentrations of soluble sugars in the two study regions. The distribution and accumulation of certain minerals (e.g. Sodium and Potassium) in the plant can be modified to increase resistance to heat stress. [ABSTRACT FROM AUTHOR]

The evaluation of water resources management practices is essential for water usage decisions in regions with limited water resources. The literature provides numerous assessment frameworks, but many ignore the unique characteristics and conditions of some special arid and semi-arid regions, such as the Gulf Cooperation Council (GCC) countries, which lack any permanent rivers or lakes. Thus, this study, the first in a two-part series, seeks to develop a conceptual Sustainable Water Resources Management Assessment Framework (SWRM-AF). General and particular criteria explain how components and indicators were identified. The conceptual SWRM-AF provided here has four components (environment, economy, society, and infrastructure) and 24 indicators. Almost every indicator has been selected from the literature and is briefly explained and justified. This research presents, possibly for the first time, clear and straightforward directions for evaluating each indicator in colour-coded tables. To create a more holistic framework for arid and semi-arid regions, social indicators like "intervention acceptability" and environmental indicators for assessing the impacts of desalination treatment plants have been added to form a unique framework applicable to such regions. Therefore, the components and indicators of conceptual SWRM-AF could work collectively to aid the process of decision-making. The next phase is validating this framework using a participatory approach. [ABSTRACT FROM AUTHOR]

Abstract In this study, prominent dust source areas are identified along with their plume extent using high temporal frequency satellite observations. Hourly dust plume observations of the Dust Belt from geostationary‐orbit satellites are analyzed for the 2017‐12–2022‐11 period. To identify dust source areas and their extents, we back‐track plumes to their source, assessing source areas in terms of emission frequency, contribution, and plume extent patterns. This method advances over traditional source allocation techniques that rely on polar‐orbiting satellites based on a few daily passes and meteorological wind fields for backtracking. Our findings indicate that Boreal summer is the most intense season for most sources, except in the Southern Sahara, which experiences winterly winds. Our analysis also reveals significant contributions from regions within the Sahara that experience expansive but infrequent dust storms, highlighting the importance of considering both frequency and magnitude in understanding dust emissions.

Abstract Changes in water availability have a substantial impact on the sustainability and maintenance of agriculture, with water footprint (WF) being a robust methodology to assess these transformations. The Guadalupe Valley is one of the places with the highest agricultural production in Mexico. Despite its semi-arid climatic conditions, it provides high-quality crops that are well-positioned in the world. The historical trend of rainfall and temperatures between 1987 and 2017 was analyzed to identify climatic patterns in the territory. Through the calculations of the water footprint of Grapevine and Olive crops, the sensitivity of the crops to recurrent water deficit and their adaptation in their yields to drought episodes was identified. The reduction in precipitation and occurrence of extreme temperatures have contributed significantly towards augmenting crop evapotranspiration and, consequently, intensifying crop irrigation demands. As a result, there has been an apparent increase in the consumption of WFagricultural since 2007. Thus, the period of highest WFagricultural consumption was 2014 (Extremely dry), as opposed to 2011 (Very wet). In particular, the lowest WFgreen consumptions were observed in extremely dry years, that is, > 20% of the WFagricultural intensifying drought events. Therefore, these periods were compensated with higher uses of WFblue and WFgray, which are inversely correlated with precipitation, where vine crops consume 73% more WFagricultural compared to olive plantations, showing greater interannual variability. These results contribute to analyzing the temporal evolution of water consumption for agriculture, providing a basis for rational water use strategies.

Considering several logistical limitations associated with live trapping in arid environments, owl pellet analysis provides a potentially useful alternative to estimate small mammal diversity. Owl pellet analysis has been used to estimate local small mammal diversity under the assumption that the method can reliably reflect the composition of local small mammal assemblages. However, the validity of owl pellet contents for use in ecological assessments has not been established. Thus, the present study aimed to determine the potential for eastern barn owl (Tyto delicatula) pellet analysis to improve the monitoring of small mammals in arid Australia. We analysed two ecological datasets from Pilungah Reserve on the northern boundary of the Simpson Desert in central Australia to assess their effectiveness for detecting expected small mammal species: 250 owl pellets collected from a known roosting site and 5 years of small mammal records from historical, long‐term trapping surveys. Species composition and detection probability of mammals varied depending on the method used. Owl pellet analysis returned higher species richness overall, while traditional trapping methods indicated a higher probability of detecting certain mammal species (e.g., the wongai ningaui Ningaui ridei, brush‐tailed mulgara Dasycercus blythi and the hairy‐footed dunnart Sminthopsis hirtipes). Importantly, analysis of owl pellets revealed two mammal species that had never been detected at the study site (dusky hopping mouse Notomys fuscus and Carpentarian false antechinus Pseudantechinus cf. mimulus). We suggest that owl pellet analysis could be particularly valuable when used as a precursor or in concert with traditional trapping to monitor and assist in the conservation of small mammal species in arid environments. [ABSTRACT FROM AUTHOR]

A near-global framework for automated training data generation and land cover classification using shallow machine learning with low-density time series imagery does not exist. This study presents a methodology to map nine-class, six-class, and five-class land cover using two dates (winter and non-winter) of a Sentinel-2 granule across seven international sites. The approach uses a series of spectral, textural, and distance decision functions combined with modified ancillary layers (such as global impervious surface and global tree cover) to create binary masks from which to generate a balanced set of training data applied to a random forest classifier. For the land cover masks, stepwise threshold adjustments were applied to reflectance, spectral index values, and Euclidean distance layers, with 62 combinations evaluated. Global (all seven scenes) and regional (arid, tropics, and temperate) adaptive thresholds were computed. An annual 95th and 5th percentile NDVI composite was used to provide temporal corrections to the decision functions, and these corrections were compared against the original model. The accuracy assessment found that the regional adaptive thresholds for both the two-date land cover and the temporally corrected land cover could accurately map land cover type within nine-class (68.4% vs. 73.1%), six-class (79.8% vs. 82.8%), and five-class (80.1% vs. 85.1%) schemes. Lastly, the five-class and six-class models were compared with a manually labeled deep learning model (Esri), where they performed with similar accuracies (five classes: Esri 80.0 ± 3.4%, region corrected 85.1 ± 2.9%). The results highlight not only performance in line with an intensive deep learning approach, but also that reasonably accurate models can be created without a full annual time series of imagery. [ABSTRACT FROM AUTHOR]

The objective was to determine a mathematical model to calculate the deposition velocity of the mud resulting from the washing of aggregates from the Jobo Base Business Unit of Sagua de Tánamo, which is transported by pipelines. Sampling, granulometric and densimetric analyzes were carried out and a complete factorial experiment design with four tests and two replications each was used. The input variable, percentage of solids, was studied at four levels (4%, 12%, 20% and 28%). It was determined that the clay contained in the mud, due to its predominant granulometry of less than 40 µm, classifies as silt. It was also revealed that the density of the solid is 1,901 kg/m3. The results of the deposition velocity determined by indirect measurement and those predicted by calculations using the Durand model were compared, with the aim of improving its precision and reliability, obtaining a relative coincidence error of less than 5%. A correction function is determined that quantifies the relationship between gravitational sedimentation velocity and deposition velocity. [ABSTRACT FROM AUTHOR]

The seed germination dynamics of Acacia nilotica, Bauhinia rufescens, Faidherbia albida , and Piliostigma reticulatum were investigated over 28 days. Seeds were pretreated with concentrated sulfuric acid. Determined germination parameters included germination energy, germination period, germination capacity, germination inertia, and viability loss. Seeds exposed to sulfuric acid for extended periods (30, 40, 50, and 60 min) exhibited a higher germination rate ( α = 0.05). For A. nilotica seeds, the 50 min acid treatment resulted in the highest germination energy of 85.5% and germination capacity of 89.5% ( P = 0.001); conversely, the 60-min treatment yielded the highest germination energy and capacity, both 96.5% ( P = 0.079), for P. reticulatum . In the case of B. rufescens , the 30-min treatment led to the highest germination energy of 93% and germination capacity of 88% ( P = 0.001). For F. albida, all acid treatments resulted in 100% for both germination energy and germination capacity ( P = 0.621). Viability losses for A. nilotica and P. reticulatum were higher (32 and 30%, respectively) than those for B. rufescens and F. albida , which were 19.5 and 6%, respectively ( P = 0.000). Generally, higher germination energy resulted in lower viability loss, dependent on the species. Analyses of germination inertia and viability loss suggest that seeds of A. nilotica and P. reticulatum possess a greater ability to survive in arid land climates than those of B. rufescens and F. albida. However, due to the advantage of lower viability loss, B. rufescens and F. albida should be preferred for the natural restoration of arid land ecosystems where seed availability is a major concern.

In the context of climate change, studying changes in rainfall patterns is a crucial area of research, remarkably so in arid and semi-arid regions due to the susceptibility of human activities to extreme events such as droughts. Employing predictive models to calculate drought indices can be a useful method for the effective characterization of drought conditions. This study applies two type of machine learning methods—long short-term memory (LSTM) and Neural Hierarchical Interpolation for Time Series Forecasting (N-HiTS)—to develop and deploy artificial neural network models with the aim of predicting the regional standardized precipitation index (SPI) in four regions of Zacatecas, Mexico. The predictor variables were a set of climatological time series data spanning from 1964 to 2020. The results suggest that the N-HiTS model outperforms the LSTM model in the prediction and forecasting of SPI time series for all regions in terms of performance metrics: the Mean Squared Error, Mean Absolute Error, Coefficient of Determination and ξ correlation coefficient range from 0.0455 to 0.5472, from 0.1696 to 0.6661, from 0.9162 to 0.9684 and from 0.9222 to 0.9368, respectively, for the regions under study. Consequently, the outcomes revealed the successful performance of the N-HiTS models in accurately predicting the SPI across the four examined regions.

Populations inhabiting several biomes may experience different abiotic and biotic conditions, exerting local selection pressures. Temperature and water regimes are interconnected variables, that may differ between biomes, and greatly influence ecophysiological traits, such as metabolic and evaporative water loss rates. We hypothesized that Ptyodactylus guttatus (Sinai Fan‐fingered Gecko) individuals, which occupy the Mediterranean and desert biomes across Israel, would follow the "metabolic cold adaptation" hypothesis and be adapted to the microclimate in the biome they inhabit. We thus predicted that desert individuals would prefer lower temperatures, and have lower resting metabolic rates and evaporative water loss rates at higher ambient temperatures than Mediterranean individuals. We also predicted that Mediterranean individuals would have a better body condition than individuals from the desert, because of higher primary productivity in the Mediterranean biome, and would therefore have higher mite loads. We further predicted that geckos from the desert would have longer limbs, enabling them to lose more heat to the environment, according to Allen's rule. To test these hypotheses, we measured the temperature preferences, field body temperatures, resting metabolic rates, evaporative water loss rates, body conditions, mite loads, and limb lengths of 82 P. guttatus individuals collected from four localities two from the desert biome and two from the Mediterranean biome. There were no significant differences in any of the tested traits when comparing between biomes. However, we found some differences in the evaporative water loss rates, body temperatures, body condition, and forelimb lengths between the northernmost and southernmost, and driest and wettest localities, supporting some of our predictions. Our results highlight the importance of the resolution of the analysis. Although some ecophysiological traits of P. guttatus seem to be conserved across localities and biomes, thermal plasticity in these traits may have helped this species reach its current distribution and occupy two biomes. [ABSTRACT FROM AUTHOR]

Context. Seeding is common practice for ecological restoration, but establishment rates can be low. For seeds to successfully establish they must transition through early life stages of germination, emergence, and (initial) survival. Examining these demographic processes for seeds sown under a range of abiotic conditions can identify failure points and inform techniques to improve seed use. Aims. Here we quantified seed and seedling life-stage transitions in five reconstructed soils across four varying levels of simulated rainfall using five species (Acacia hilliana, Acacia inaequilatera, Indigofera monophylla, Triodia pungens, and Triodia wiseana) commonly seeded for mined land restoration of the Pilbara bioregion in north-west Western Australia. Methods. Germination, emergence, and survival were measured over a 6 week period and transition probabilities between each life-stage transition were modelled for each treatment combination. Key results. For four species, both rainfall amount and/or soil substrate significantly influenced germination probability. Rainfall was the more significant determinant, with germination greatest under the higher rainfall regimes of 120-280 mm, irrespective of soil type. Following germination, emergence of both Acacia spp. was positively influenced by soils containing topsoil, suggesting the microenvironment of soils containing topsoil was most favourable during this emergence phase. The effect of substrate was less clearcut for I. monophylla and Triodia spp, where emergence was most limited in substrates comprised solely of overburden waste material and the lowest rainfall regime exacerbated emergence failure, relative to germination success. When compared to the well-watered, 100% topsoil substrate, seedling survival of all species was most constrained in the 100% overburden waste, demonstrating these reconstructed mining substrates compromise seedling recruitment. Conclusions. This study underscores that successful seedling recruitment in this ecosystem is dependent on frequent, and repeated, rainfall events above a certain threshold (≥120 mm) and highlights the beneficial effects of sowing seeds in a substrate containing topsoil. Implications. Future seeding technologies should focus on improving the moisture relations of the microsite to offset the recruitment challenges experienced by seeds sown in hostile growing environments such as the overburden wastes tested here. [ABSTRACT FROM AUTHOR]

The seed germination dynamics of Acacia nilotica, Bauhinia rufescens, Faidherbia albida, and Piliostigma reticulatum were investigated over 28 days. Seeds were pretreated with concentrated sulfuric acid. Determined germination parameters included germination energy, germination period, germination capacity, germination inertia, and viability loss. Seeds exposed to sulfuric acid for extended periods (30, 40, 50, and 60 min) exhibited a higher germination rate (α = 0.05). For A. nilotica seeds, the 50 min acid treatment resulted in the highest germination energy of 85.5% and germination capacity of 89.5% (P = 0.001); conversely, the 60-min treatment yielded the highest germination energy and capacity, both 96.5% (P = 0.079), for P. reticulatum. In the case of B. rufescens, the 30-min treatment led to the highest germination energy of 93% and germination capacity of 88% (P = 0.001). For F. albida, all acid treatments resulted in 100% for both germination energy and germination capacity (P = 0.621). Viability losses for A. nilotica and P. reticulatum were higher (32 and 30%, respectively) than those for B. rufescens and F. albida, which were 19.5 and 6%, respectively (P = 0.000). Generally, higher germination energy resulted in lower viability loss, dependent on the species. Analyses of germination inertia and viability loss suggest that seeds of A. nilotica and P. reticulatum possess a greater ability to survive in arid land climates than those of B. rufescens and F. albida. However, due to the advantage of lower viability loss, B. rufescens and F. albida should be preferred for the natural restoration of arid land ecosystems where seed availability is a major concern. [ABSTRACT FROM AUTHOR]

Under the global crisis of energy shortage and environmental pollution, the climate responsive strategies used in vernacular buildings have attracted much attention for their potential to reduce energy consumption and carbon emissions. However, the relationships between these traditional climatic strategies were not precisely perceived, which may cause the inapplicability of these strategies for contemporary rural houses. In this paper, taking the Turpan vernacular buildings in arid region of China, the climate responsive strategies of buildings in the most significant periods such as the Gaochang period (before 1318), the Khanate and Republican period (1318–1949), the Modern period (1949–2010), and the Contemporary period (2011–present) were summarized. In addition, two different types of climatic strategies organizations, namely multilayer spaces and integrated building envelopes, were identified based on the temperature difference measurement and comparative analysis. The assessment of thermal performance of the organizations was conducted by the methodology of software simulation. Furthermore, the applicability of the organizations in rural areas was discussed, and a new combined organization was proposed. Consequently, this study can contribute to provide the main approaches for climatically responsive rural houses.

Premise of research. Woody plant expansion is a global problem in which trees and/or shrubs replace herbaceous species. Often the woody plants are native species, and the expansion may be attributable either to natural stochasticity or to changes in management of grazing or fire. In other cases, woody plant species are expanding their historic range, and changes in management may be insufficient to explain observed changes in range. One possible mechanism is adaptation of populations at the range edge to the local environment. Methodology. We investigated drought responses of plants sourced from three populations of the widespread, grassland-encroaching Juniperus virginiana and one population of the more drought-resistant Juniperus scopulorum. Seedlings of the four different populations were grown in a common garden in northeast Ohio, part of the native range of J. virginiana. We exposed plants to either an acute or chronic drought and determined water potential at 50% loss of function (P 50) for shoots. Pivotal results. The most resistant shoot P 50 measured ranged from 2.7 to 4.7 MPa less negative than P 50 reported in the literature for woody tissues. Juniperus virginiana plants sourced from the most arid site maintained high stomatal conductance when water was available and retained hydraulic conductance at lower water potentials compared to J. virginiana from wetter locations. Juniperus virginiana from the most arid site exhibited the largest hydraulic safety margin, with shoot P 50 as much as 3.25 MPa less negative than minimum shoot water potentials measured. Conclusions. Our data show that estimates of Juniperus spp. drought tolerance based on woody tissues misrepresent actual plant drought response. Juniperus virginiana plants from more arid sites exhibit a more exploitative water use strategy, which could promote expansion by facilitating rapid water uptake in pulse-driven systems, while a decrease in hydraulic conductance in shoots could promote survival by preventing hydraulic failure of more costly woody tissue. [ABSTRACT FROM AUTHOR]

Litter decomposition is a key ecosystem process that determines rates of carbon and nutrient cycling. Photodegradation and soil-litter mixing have emerged as important drivers of dryland litter decomposition, but how these processes interact with decomposing microorganisms has received less attention. In this study, we examined the effects of ultraviolet-B radiation (UV-B; 280–315 nm) and soil-litter mixing on the decomposition of litter and its associated microbial community in an arid shrubland. We performed a full factorial litter decomposition experiment using leaf litter from a dominant shrub (Prosopis velutina) and a dominant grass (Eragrostis lehmanniana) that were exposed to solar radiation with near-ambient or attenuated UV-B, and were either soil-free or soil-covered; we then quantified litter decomposition and microbial community composition over a 12 month period. In general, shrub litter decomposed more rapidly than grass litter regardless of soil coverage, likely due to its lower C:N. Attenuation of UV-B had modest effects on decomposition but UV-B exposure did increase fungal biomass, perhaps reflecting facilitative aspects of photodegradation. Both bacteria and fungi emerged as important regulators of decomposition, and microbial decomposition was indirectly mediated by litter C:N, soil coverage, and UV-B effects on the microbial community. Bacterial colonization was inhibited in soil-free treatments, but was facilitated when litter was soil-covered. These findings suggest that UV-B may play an important role in facilitating fungal decomposition of litter, while soil-litter mixing is fundamental for promoting bacterial decomposition of litter. Highlights: Soil-litter mixing enhanced bacterial colonization of litter. Fungi are present on dryland litter regardless of soil and UV-B conditions. Soil-litter mixing initially accelerated litter decomposition but subsequently reduced it. [ABSTRACT FROM AUTHOR]

Sand dunes cover more than half a million hectares of Khuzestan Province in Iran. These areas are a serious threat to agricultural lands, buildings, and industrial facilities. Knowing the characteristics of these lands helps a lot to manage and control this threat. This research was done to determine the characteristics of sand dunes of Khuzestan Province and their management. The results showed that the dynamic characteristics of sand dunes, such as salinity, are different depending on the location and direction of the prevailing wind. However, the organic carbon, cation exchange capacity, and acidity (pH) were similar in all regions. Soluble K was inversely related to salinity. In the western regions, carbonates (lime and dolomite) along with quartz, kaolinite, chlorite, and illite were the dominant minerals, and smectite, palygorskite, and vermiculite were in the next order. The southeastern parts had a similar composition, but the proportion of minerals was different based on the location, especially for polygorskite. The proportion of smectite, polygorskite, and sepiolite minerals was high in the direction of prevailing winds, but their amount decreased in the inner parts. Sepiolite was observed only in the southeastern regions, which was related to the origin of gypsum soils in the neighborhood areas. A similar composition of these minerals and their proportion was also seen in the deeper parts. The similarity of the sand dunes minerals shows that they have the same origin and their similarity with the composition of soil minerals in the plains of Khuzestan indicating that these sands were formed from the wind erosion of the plain during different dry periods. [ABSTRACT FROM AUTHOR]

Decision support system tools such as crop models and considering the uncertainties associated with them are important for making an informed decision to fill the yield gap in farms and increase food security. This study's objective was to identify and quantify the degree to which crop management practices, as well as climate and soil, affected the uncertainty of total biomass, evapotranspiration, and water productivity of silage maize by using a crop model and spatiotemporal input data. Using a calibrated crop model (DSSAT) and pSIMS platform, three planting dates by considering ten ensemble weather data and three soil profile data were simulated for the time period between 2002 and 2017 with a 2 km × 2 km resolution across maize production areas with arid and Mediterranean climates in Isfahan province, Iran. Additionally, the findings were used to determine the yield gap in the studied area to identify opportunities to boost food production. Our results showed larger uncertainty in Mediterranean climates than in arid climates, and it was more affected by planting date than weather parameters and soil profile. The accuracy of total biomass prediction by using pSIMS-CERES-Maize based on the spatiotemporal input data was 1.9% compared to field experimental data in the dry climate, and the yield gap based on the comparison of modified-pSIMS-CERES-Maize and reported biomass was 6.8 to 13 tons ha−1 in the arid and Mediterranean climate. Generally, all results represented the importance of using crop models and considering spatiotemporal data to increase reliability and accuracy, especially in Mediterranean climates, and their potential to increase food production in developing countries with limited water resources and poor agriculture management. [ABSTRACT FROM AUTHOR]

Transporting water to supply livestock is one of the great challenges of the drylands. Ranchers usually make impoundments, filled by runoff, to access freshwater for cattle supply in flat rangelands. The aim of this study was to understand rainfall-runoff generation and water storage temporal dynamics of impoundments in the Dry Chaco rangelands (Argentina). Thus, we instrumented six impoundments over three consecutive years and analyzed water storage data by developing a probabilistic model. For all impoundments, the rainfall event size thresholds to generate runoff presented values between 15 and 33 mm. Once they reached this threshold, the water gain response slopes presented values between 19 and 99 m3 mm−1. Loss patterns of water storage were described by exponential or linear functions. The predicted water storage dynamics presented high accuracy with the observed time series for all impoundments (RMSD between 380 and 1320 m3). The model only needs daily rainfall and air temperature to be run, making it easy to be used by scientists, ranchers, or local decision makers. It may be used to explore the hydrological functioning of small and seasonal water bodies of different sites of the world exposed to drought episodes caused by high climate variability and/or climate change. [ABSTRACT FROM AUTHOR]

A near-global framework for automated training data generation and land cover classification using shallow machine learning with low-density time series imagery does not exist. This study presents a methodology to map nine-class, six-class, and five-class land cover using two dates (winter and non-winter) of a Sentinel-2 granule across seven international sites. The approach uses a series of spectral, textural, and distance decision functions combined with modified ancillary layers (such as global impervious surface and global tree cover) to create binary masks from which to generate a balanced set of training data applied to a random forest classifier. For the land cover masks, stepwise threshold adjustments were applied to reflectance, spectral index values, and Euclidean distance layers, with 62 combinations evaluated. Global (all seven scenes) and regional (arid, tropics, and temperate) adaptive thresholds were computed. An annual 95th and 5th percentile NDVI composite was used to provide temporal corrections to the decision functions, and these corrections were compared against the original model. The accuracy assessment found that the regional adaptive thresholds for both the two-date land cover and the temporally corrected land cover could accurately map land cover type within nine-class (68.4% vs. 73.1%), six-class (79.8% vs. 82.8%), and five-class (80.1% vs. 85.1%) schemes. Lastly, the five-class and six-class models were compared with a manually labeled deep learning model (Esri), where they performed with similar accuracies (five classes: Esri 80.0 ± 3.4%, region corrected 85.1 ± 2.9%). The results highlight not only performance in line with an intensive deep learning approach, but also that reasonably accurate models can be created without a full annual time series of imagery.

The global distribution of footpaths and their inferred antiquity implies that they are widespread spatial and temporal anthropogenic landscape units. Arid environments are of special interest for investigating historically used footpaths, as older routes may preserve better due to minimal modern impact and slower pedogenic processes. Here we examine footpaths in the Judean Desert of the southern Levant, a human hotspot throughout the Holocene. We studied one modern and two archaeological footpaths (one attributed to the Early Bronze Age and one to the Roman period) using micromorphology, bulk samples laboratory analysis, and remote sensing. Field observations and color analysis indicate that footpaths in the studied arid limestone environment can result in brighter surface color than their non-path surroundings. Similar color changes are reflected using both laboratory analysis and high-resolution remote sensing, where the difference is also significant. Microscopically, the footpaths studied tend to be less porous and with fewer biogenic activities when compared to their non-path controls. However, the two ancient footpaths studied do exhibit minimal indicators of biogenic activities that are not detectable in the modern footpath sample. Our study shows that high-resolution remote sensing coupled with micromorphology, while using appropriate local modern analogies, can help to locate and assess both the environmental effect and the antiquity of footpaths.

Many rail species' distribution and habitat requirements are poorly known. We conducted a survey of the distribution of the Water Rail Rallus aquaticus across Algeria and investigated its possible nesting in the Sahara. Between 2002 and 2008, water rails were recorded in nine sites across Algeria and were found to breed in Lake Fetzara. In 2022, the species was recorded at yet another site, El Ménia, where two nests were found to contain clutches of three and seven eggs, respectively. This is the first unequivocal record of the Water Rail breeding in the Sahara. [ABSTRACT FROM AUTHOR]

Precipitation variability and heatwaves are expected to intensify over much of inland Australia under most projected climate change scenarios. This will undoubtedly have impacts on the biota of Australian dryland systems. However, accurate modelling of these impacts is presently impeded by a lack of empirical research on drought/heatwave effects on native arid flora and fauna. During the 2018–2021 Australian drought, many parts of the continent's inland experienced their hottest, driest period on record. Here, we present the results of a field survey in 2021 involving indigenous rangers, scientists and national parks staff who assessed plant dieback during this drought at Uluru‐Kata Tjuta National Park (UKTNP), central Australia. Spatially randomized quadrat sampling of eight common and culturally important plants indicated the following plant death rates across UKTNP (in order of drought susceptibility): desert myrtle (Aluta maisonneuvei subsp. maisonneuvei) (91%), yellow flame grevillea (Grevillea eriostachya) (79%), Maitland's wattle (Acacia maitlandii) (67%), waxy wattle (A. melleodora) (65%), soft spinifex grass (Triodia pungens) (53%), mulga (A. aneura) (42%), desert oak (Allocasuarina decaisneana) (22%) and quandong (Santalum acuminatum) (0%). The sampling also detected that seedling recruitment was absent or minimal for all plants except soft spinifex, while a generalized linear mixed model (GLMM) indicated two‐way interactions among species, plant size and stand density as important predictors of drought survival of adult plants. A substantial loss of biodiversity has occurred at UKTNP during the recent drought, with likely drivers of widespread plant mortality being extreme multi‐year rainfall deficit (2019 recorded the lowest‐ever annual rainfall at UKTNP [27 mm]) and record high summer temperatures (December 2019 recorded the highest‐ever temperature [47.1°C]). Our findings indicate that widespread plant death and extensive vegetation restructuring will occur across arid Australia if the severity and frequency of droughts increase under climate change. [ABSTRACT FROM AUTHOR]

Under the global crisis of energy shortage and environmental pollution, the climate responsive strategies used in vernacular buildings have attracted much attention for their potential to reduce energy consumption and carbon emissions. However, the relationships between these traditional climatic strategies were not precisely perceived, which may cause the inapplicability of these strategies for contemporary rural houses. In this paper, taking the Turpan vernacular buildings in arid region of China, the climate responsive strategies of buildings in the most significant periods such as the Gaochang period (before 1318), the Khanate and Republican period (1318–1949), the Modern period (1949–2010), and the Contemporary period (2011–present) were summarized. In addition, two different types of climatic strategies organizations, namely multilayer spaces and integrated building envelopes, were identified based on the temperature difference measurement and comparative analysis. The assessment of thermal performance of the organizations was conducted by the methodology of software simulation. Furthermore, the applicability of the organizations in rural areas was discussed, and a new combined organization was proposed. Consequently, this study can contribute to provide the main approaches for climatically responsive rural houses. [ABSTRACT FROM AUTHOR]

The aim of the present work is to determine harmful and beneficial insects associated with tomato greenhouse cultivation in the arid region of El-Outaya (Biskra, Algeria). Insect trapping was conducted using yellow water plates and yellow glue traps. Faunistic data have revealed the presence of 2754 individuals distributed on seven orders, 33 families and 38 species of insects. From specific point of view, the majority of these insects were represented by potential insect pests with sixteen phytophagous species amongst them three species attacking tomatoes. Whereas nine species are predators and two pollinators. Our results can be used to plan strategies for the management of harmful pests and beneficial insects associated with the tomato greenhouse crops in this locality. [ABSTRACT FROM AUTHOR]

The Algerian Saharan rangelands are an arid ecosystem characterized by limited soil, water, and vegetation resources, which make it very susceptible to degradation. This research focuses on the diachronic assessment and multi-temporal mapping of the degradation of steppe vegetation in the south of Biskra during the period 1987–2019, using remote sensing data (MSAVI index), for extracting spatiotemporal data to monitor the rangeland vegetation dynamics. We examined demographic evolution, number of livestock, and land use from quantitative data. The results show that during this period, the landscape of the region changed considerably. The area of rangelands decreased from 19,939 ha (1987) to 3605 ha (2019), where 58% of the pre-existing vegetation was transformed into bare soil. This study confirmed that the rangeland vegetation health is closely related to climate, and its degradation is mainly due to the recurrence, duration, severity, and magnitude of drought events. Manmade activities were also a determinant factor of long-term degradation of the rangeland, such as the expansion of new land development areas that increased from 3754 ha (1987) to 24,410 ha (2019). This trend was found throughout the region, including predominantly pastoral regions such as Oumache and El Haouch, leading to overgrazing with a loss of about 2% of vegetation cover. All these factors have led to a severe and continuous degradation of pastoral resources in a vulnerable environment. The preservation of these limited resources requires appropriate management of the ecosystem and a rational exploitation of its vegetation, soil, and water resources. [ABSTRACT FROM AUTHOR]

Irruption of herbivore populations due to the extirpation of predators has led to dramatic changes in ecosystem functioning worldwide. Herbivores compete with other species for their primary source of nutrition, plant biomass. Such competition is typically considered to occur between species in closely related clades and functional groups but could also occur with detritivores that consume senescent plant biomass. In this study, we tested predictions that in ecosystems where herbivores are not regulated by predators, their indirect impacts on dead vegetation increase with primary productivity and extend to termites that feed on senescent vegetation. We compared dead vegetation cover and termite activity in herbivore exclosures and associated grazed plots at three locations situated along a rainfall gradient in arid Australia where kangaroo populations have irrupted. Dead vegetation cover and termite activity increased with rainfall in ungrazed plots but showed a negligible response to rainfall in grazed plots. Our results suggest that grazing can disrupt the flow of energy to detritivores and decouple the relationship between termite activity and primary productivity. Such disruption could have far‐reaching impacts on arid ecosystems because many organisms sit within "brown food webs" that are sustained by energy derived from the decomposition of senescent plant tissues. [ABSTRACT FROM AUTHOR]

There have been few attempts to estimate the effects of land use and land cover (LULC) on ecosystem services in desert-oasis ecotones, which are recognized as critical ecological barriers and buffers that prevent deserts from expanding into oases. This research investigated how remote sensing and geographic information technology may be used to monitor changes in LULC in the Cholistan desert and the Bahawalpur region of Pakistan between the years 2015 and 2022. The objective of this research was to identify thematic and statistical shifts in LULC in the study area due to various human interventions in the area. Landsat-8 images were processed using the maximum likelihood supervised classification technique using 500 training samples to categorize the study area into four LULC classes, i.e., desert/barren land, waterbodies, vegetation, and built-up areas, with an overall accuracy of 93% and 98% for 2015 and 2022, respectively. Results indicate a significant expansion in built-up area in 2022, which is up to 43%, agriculture and vegetation area declined by 8%, waterbodies decreased by 41%, and desert area decreased by 2% when compared with 2015. The change detection approach revealed that agricultural land was directly encroached on by rapidly increasing built-up area and urbanization as the area had an overall 19% rise in population growth within eight years with an annual growth rate of more than 3%. This study will be helpful to assess the quantity of spatial and temporal changes in the desert ecosystem, which is usually ignored by policymakers and governments due to less economic activity, although it plays a huge role in biodiversity conservation and balancing the regional ecosystem. [ABSTRACT FROM AUTHOR]

A previous study on the feeding habits of Moorish tortoises in west-central Morocco suggests that these animals are selective herbivores, but the nutritional consequences have not been examined. Because of the potassium excretion load, which requires water and/or nitrogen loss, we predicted that tortoises do not have salt glands. Moorish tortoises prefer plants rich in water and protein but low in potassium (PEP index). To this end, we studied the spring diet of adult tortoises in an arid steppe in west-central Morocco during two seasons of relatively dry years (2011-2012) using feces analyses. We also estimated the relative abundance of potential food plants by stratified sampling under the canopy of jujube bushes Ziziphus lotus. We statistically compared diet to plant abundance. Finally, we assessed plant species' nutritional composition (water, crude protein, and potassium) available to tortoises. Results showed that species assemblages differed significantly between the two plant communities in both years. Nevertheless, tortoises consumed only about 5-6 and nearly the same species at the study site in 2011 and 2012, respectively. The plants consumed by the tortoises had the highest positive PEP index values indicating that there was more water and nitrogen in the food than is needed to excrete potassium. [ABSTRACT FROM AUTHOR]

Livestock production in drylands requires consideration of the ecological applications of ecohydrological redistribution of water. Intensive cattle trampling and the associated increase of surface runoff are common concerns for rangeland productivity and sustainability. Here, we highlight a regional livestock production system in which cattle trails and trampling surrounding an artificial impoundment are purposely managed to enhance redistribution and availability of water for cattle drinking. Based on literature synthesis and field measurements, we first describe cattle production systems and surface water redistribution in the Dry Chaco rangelands of South America, and then develop a conceptual framework to synthesize the ecohydrological impacts of livestock production on these ecosystems. Critical to this framework is the pioshere—a degraded overgrazed and overtrampled area where vegetation has difficulties growing, usually close to the water points. The Dry Chaco rangelands have three key distinctive characteristics associated with the flat sedimentary environment lacking fresh groundwater and the very extensive ranching conditions: (1) cattle drinking water is provided by artificial impoundments filled by runoff, (2) heavy trampling around the impoundment and its adjacent areas generates a piosphere that favors runoff toward the impoundment, and (3) the impoundment, piosphere, and extensive forage areas are hydrologically connected with a network of cattle trails. We propose an ecohydrological framework where cattle transit and trampling alter the natural water circulation of these ecosystems, affecting small fractions of the landscape through increased runoff (compaction in piosphere and trails), surface connectivity (convergence of trails to piosphere to impoundment), and ponding (compaction of the impoundment floor) that operate together making water harvesting and storage possible. These effects have likely generated a positive water feedback on the expansion of livestock in the region with a relatively low impact on forage production. We highlight the role of livestock transit as a geomorphological agent capable of reshaping the hydrology of flat sedimentary rangelands in ways that can be managed positively for sustainable ranching systems. We suggest that the Dry Chaco offers an alternative paradigm for rangelands in which cattle trampling may contribute to sustainable seminatural production systems with implications for other dry and flat rangelands of the world. [ABSTRACT FROM AUTHOR]

Underground water resources are one of the most valuable vital resources for mankind. Groundwater is used as drinking water and for agricultural irrigation. However, in recent years, it has been exposed to dangerous pollution, mainly due to man-made reasons. The study area is located in the Upper Mesopotamian region, where dry agriculture has been practiced since ancient times, which has semi-arid characteristics and where important civilizations lived. In this direction, the changes in groundwater quality were investigated with seasonal, annual samples taken from selected wells in Mardin Kiziltepe Plain in Upper Mesopotamia region and representing the plain in general and were subjected to water quality classifications. Statistical analyses were carried out on EC and NO3- parameters, which are important in determining the quality of groundwater. The results obtained were interpreted, evaluated in terms of drinking and agricultural uses, and it was observed that there were no non-standard values. In addition, the study area will be opened for irrigation in the near future within the framework of GAP, the largest integrated irrigation project in Turkey. This study, which is the first scientific research to be carried out before intensive irrigation, will be the first memory that will provide a very important data set for the region and will be recorded. In addition, the results of the study will be the basis for the comparison of the research to be carried out after the transition to irrigated agriculture depending on the GAP and the pre-irrigation data. [ABSTRACT FROM AUTHOR]

In water‐stressed hyperarid basins, questions mount over the impacts of anthropogenic groundwater extraction and climate‐driven perturbations on groundwater‐surface water interactions and the resilience of ecosystem‐critical surface water. Coupling groundwater with surface water observations from Sentinel‐2 data provides an unprecedented opportunity to evaluate surface water connectivity with local aquifers following intense precipitation events in arid basins. Surface water area and groundwater level data were analyzed for trends following precipitation, including peak lag time, post‐peak recession rates, and changes in hydraulic gradients. Results indicate variable connectivity following large precipitation events between surface water change and groundwater level fluctuations in the upgradient freshwater aquifer, whereas the downgradient brine‐to‐brackish area of the aquifer indicated virtually no connectivity with the aquifer. Comparison between precipitation and surface water response indicate distinct responses based on the physical relationship of the surface water body with the brine‐to‐brackish area of the aquifer. Lumped parameter modeling of surface water inundation also constrains the possible hydrologic dynamics of the post‐precipitation response. While modeled influx to surface water seems primarily controlled by watershed hydraulics rather than direct hydraulic connectivity of the aquifers, the relationship between surface water and adjacent groundwater levels coupled with surface water area indicates that local aquifers are primarily connected to the surface water bodies through discharge via subsurface infiltration. Modeling results imply that the existence of brine‐adjacent surface water in arid basins relies on upgradient discharge from freshwater aquifers. Our results further support that marginal surface water systems can serve as a critical recharge mechanism to local aquifers. Plain Language Summary: Surface water is important for desert ecosystems, but the future of surface water remains uncertain because of climate change and human consumption. Understanding how surface water responds to precipitation and interacts with groundwater is useful for better predicting future water availability. Advancements in the quality of satellite imagery provide an opportunity to combine satellite data with rain gauge and water level data to investigate the connection of surface water to rainfall patterns and groundwater. Observations from flooding behavior show two different types of surface water. Both types can be categorized by proximity to the brine that exists in the aquifer underlying the basin floor: transitional pools occur at the edge of the transition to brine while terminal lagoon systems occur in the brackish groundwater zone. Calculations indicate that the two groups have different inflow and outflow mechanisms that occur over varying timescales. These mechanisms indicate that intense rainfall events will lead to increased inundation over longer periods of time for transitional surface water bodies. However, despite rapid rates of recession, terminal pools will also experience prolonged inundation above background levels for up to a year after large rainfall events because of increased spring discharge from rainfall‐driven recharge to groundwater. Key Points: Post‐precipitation inflow and outflow mechanisms of salar‐adjacent surface water are distinct from recharge and discharge in local aquifersSurface water response to precipitation can be predicted and categorized based on its position to the brine groundwater and the salt flatSurface water resilience to drought relies on groundwater discharge from upgradient springs in hyperarid basins [ABSTRACT FROM AUTHOR]

We used the mark-recapture method to gather fundamental information on the population dynamics of Ischnura elegans (Vander Linden, 1820) in an arid region of central Iran. Ischnura elegans expresses female-limited colour polymorphism. We investigated sex and female morphs differences in survival and capture probabilities, space use patterns and spatial density. We used Cormack–Jolly–Seber and spatial capture-recapture models. The estimated capture probability for males was lower than females. The survival probability was not different between either males and females or gynomorphs and andromorphs. We found support for sex differences in density and detection probability, and female morphs differences in density, space use and detection probability. Based on our results the extreme conditions of arid regions can lead to a male-biased dispersal. Our findings also confirm the existence of behavioural differences between andromorph and gynomorph females and suggest a within species spatial habitat partitioning. [ABSTRACT FROM AUTHOR]

Landscape‐scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial–environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision‐making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial–environmental associations and linking them to life‐history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision‐making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally. [ABSTRACT FROM AUTHOR]

The influence of resource availability on ecosystem function varies spatially and temporally, among and within ecosystems. Dramatic shifts in moisture‐driven resources can drive bottom‐up effects on animal behaviours and distributions. Further, complexity arises when landscapes are influenced by large mammalian grazers and predator‐induced trophic cascades, such as those mediated by the dingo (Canis familiaris (Dingo)) in the eastern arid Strzelecki Desert in Australia. During the driest two‐year period on record for this region, we investigated the persistence of avian communities associated with structurally distinct dunes and swale habitats, and across two different land management regimes (pastoral land with livestock and dingoes, and Sturt National Park managed for conservation without these animals). We grouped all birds into dietary functional groups to infer patterns of habitat use associated with available resources. We also compared incidental observations of the 'winter' bird community in part of the study region between the extended dry period of 2018/2019 and wet period of 2020/2021. Despite habitat partitioning, the avian community did not differ between land management regimes except in species richness during the dry period, likely driven by the low numbers of birds present during the surveys. Incidental observations indicated that insectivorous and omnivorous species dominated the bird community in the dry period, with granivorous species forming a greater proportion of the bird community during wet times. Birds with completely or partially insectivorous diets dominated avian species composition on surveys in the dry period, but there were distinct structural vegetation associations among functional groups, indicating that heterogeneity in vegetation structure was likely important for the conservation of refuges, which enable the persistence of avifauna during extended dry periods. Distinct habitat type, structure and available resources shaped avian communities in this landscape, during the extremely resource‐limited extended dry period, with implications for conservation and management, particularly given the increasing drying effects of climate change. [ABSTRACT FROM AUTHOR]

Worldwide, dairy sector consumes 19% of the water in the livestock sector. However, in Latin America, the amount of water used in this sector is unknown, especially in arid zones. On the other hand, water footprint (WF) is a methodology to estimate the use of water to produce a product. The aim of this work was to estimate the WF of dairy production in the arid zone of the Peruvian central coast. Data from five dairy farms were used. The WF was calculated in its three dimensions: green water, blue water and grey water. In addition, the WF was measured for categories: feed, drinking and service. To measure the WF of feed production, the CROPWAT software was used, whilst the NRC (2001) equations were used to estimate the drinking water. The reference unit was cubic metres per kilogram of fat and protein corrected milk (FPCM). In average, 99% of the WF comes from feed production, followed by drinking water (0.4%). From the three dimensions of the WF, green water is responsible of 60% of the WF, followed by the blue water (30%). Imported water represented 63% of the WF. In general, WF of dairy production in these systems was 0.66 m3/kg FPCM. In conclusion, feed production, as the main source of WF from which most is imported, shows the possibility of reducing the WF of these systems by prioritizing and optimizing water consumption by crops using local resources with lower water requirements. [ABSTRACT FROM AUTHOR]

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Plants provide long-term and sustainable solutions to mitigate particulate matter (PM) pollution in urban environments. We evaluated total, fine, coarse and large particle trapping abilities of an equal number of common trees (Carica papaya, Citrus limon, Moringa oleifera, Ozoroa paniculosa, Peltophorum africanum, Psidium guajava) and herbaceous species (Argemone ochroleuca, Catharanthus roseus, Gomphocarpus fruticosus, Ipomoea batatas, Senna italica, Tribulus terrestris) to identify dust accumulators for Sekhukhuneland, a mining–smelting region of South Africa where desertification is becoming problematic. Scanning electron microscopy techniques were used to count and measure particles and relate leaf surface micromorphology to dust accumulation. Three tree and three herbaceous species showed superior dust collection capacity (G. fruticosus > P. guajava > I. batatas > O. paniculosa > C. roseus > M. oleifera). Variations in accumulation of PM sizes were noted among these six species and between adaxial and abaxial leaf surfaces. Compared with large PM, all plants accumulated more fine and coarse fractions which are respirable and thus hazardous to human health. Leaf surface roughness, epicuticular wax and epidermal glands improved dust accumulation. The six preferred plants may serve as forerunner species to abate PM pollution in Sekhukhuneland and other arid regions facing similar climate change and pollution challenges. [ABSTRACT FROM AUTHOR]

Study region: The study site, the Mount Bruce Flats, is located in the Pilbara, a semiarid region of northern Western Australia. Study focus: Semiarid climates are characterised by an extreme water deficit, with evaporation exceeding precipitation several-fold. Groundwater recharge is episodical and occurs only after infrequent but very large volume precipitation, while all other precipitation events are quickly lost to evaporation. We investigated the contribution of an internally drained basin to localised groundwater recharge by combining the results of calculations from various tracer methods. We developed a new mobile-immobile recharge transport model coupled with a probability model based on Markov Chain Monte Carlo simulations that combines several age and hydrochemical tracers to estimate localised infiltration. New hydrological insights for the region: The actual recharge varied greatly across the basin, being 4–5 times higher in the central part compared to the margins. The highest probability for recharge was calculated for 2.5 mm×y−1 and 12.6 mm×y−1, with a median value of 6.8 mm×y−1 while the median mobile effective porosity was low at ∼0.5 %. The flood plains overlying freshwater aquifers may contribute several times more to localised recharge than the upper parts of the catchments, which are characterised by fast runoff and a lower water retention time. Therefore, these endorheic basins could be a valuable source of water for groundwater recharge or constitute an additional hydrological challenge for mining.

In this study, we present multi-season measurements from a remote mountain peak observatory in the United Arab Emirates (UAE). During the campaign, Doppler lidar and cloud radar were employed using coordinated scan patterns, to study seedable convective clouds, and identify pre-convection initiation clear-air signatures. The instruments were employed for approximately two years in an extreme environment with a high vantage point for observing valley wind flows and convective cells. The instruments were configured to run synchronized plan position indicator (PPI) scans at 0°, 5°, and 45° elevation angles and vertical cross-section range height indicator (RHI) scans at 0°, 30°, 60°, 90°, 120°, and 150° azimuth angles. Using this output imagery, along with local C‑band radar and satellite data, we were able to identify and analyse several convective cases. To illustrate this synergy of measurements, we present two cases in unstable conditions – the 5 and 6 September 2018. In both cases, we observed areas of convergence/divergence to the south-west of the observatory, associated with wind flow around a peak 2 km to the south-west. The extension of these deformations were visible in the atmosphere as high as 3 km above sea level. Subsequently, we observed convective cells developing in the same directions – apparently connected with these phenomena. The cloud radar Doppler images provided detailed observations of cloud hydrometeor dynamics. In both convective cases, pre-convective signatures were apparent before CI, in the form of convergence, wind shear structures, and updrafts. These results demonstrate the potential of these synergetic observations for understanding convection initiation processes and in the future, to provide cloud seeding guidance via early detection of CI events.