World's Driest Research Articles

Hydraulic recharge and element dynamics during salinization in an overexploited coastal aquifer of the world's driest zone: Atacama Desert

The management of water resources in hyper-arid coastal regions is a challenging task because proper information regarding groundwater recharge and water budget is needed for maintaining the hydraulic balance in optimal conditions, avoiding salinization and seawater intrusion. Thus, this article deals with the estimation of the hydraulic recharge and the study of the effects of salinization on the dynamics of major and trace elements in an alluvial aquifer located in the world's driest zone, the northern Atacama Desert. The result of stable water isotopes (δD and δ18O) and tritium (3H) indicated that groundwater in the area is not recent, whereas 14C results estimated a groundwater residence time ranging between 11,628 and 16,067 yBP. The estimation of the artificial recharge coming from the urban water-supply-system leaks and wastewater/river-water/groundwater infiltration during irrigation was about 19.84 hm3/year, which represents an annual negative water balance of 177 hm3/year for the aquifer. The groundwater salinization triggered by seawater intrusion (up to 32.6 %) has caused the enrichment of Li, Rb, Ca, Ba, and Sr in groundwater by cationic exchange, where the excess of aqueous Na is exchanged by these elements in the aquifer sediments. Other elements such as B, Se, Si, and Sb are enriched in groundwater by ionic strength and/or anionic exchange during salinization. The heightened B concentrations derived from the B-rich alluvial sediments were higher than the limit suggested by international guidelines, representing a risk to consumers. Vanadium seems to be unaffected by salinization, whereas Pb, Mo, As, U, and Zr did not show a clear behavior during saline intrusion. Finally, this article highlights the consequences of conducting improper water management in coastal hyper-arid regions with exacerbated agriculture.

Flash floods: why are more of them devastating the world's driest regions?

Shifting weather, changing settlement patterns and a lack of preparedness mean that dryland areas are most at risk from flooding. Researchers need to focus on data collection, early-warning systems, flood protection and more. Shifting weather, changing settlement patterns and a lack of preparedness mean that dryland areas are most at risk from flooding. Researchers need to focus on data collection, early-warning systems, flood protection and more.

Geophysical studies to delineate groundwater aquifer in arid regions: A case study, Gara Oasis, Egypt

Groundwater is an important factor in establishing new urban communities, especially in coastal arid and semi-arid regions. Egypt is one of the world's driest countries, with hyper-arid territory accounting for 86% of the total area and arid and semi-arid terrain accounting for the rest. The present work aims to demonstrate the powerful integration of geophysical techniques to assess groundwater potentiality and suitability in Gara Oasis (GO), which describes a good example of Egypt's strategic southern extension of its arid north-western coast. Geophysical methods, including electrical resistivity and aeromagnetics, were used to evaluate groundwater resources. The study region reduced to pole total magnetic intensity map is subjected to digital filters that include derivatives, analytic signal, and tilt angle. The possible structures controlling the shallow and deep aquifers are delineated and integrated with geoelectric results. Moreover, two magnetic tomography sections are constructed to show the subsurface distribution of magnetic susceptibilities and formation boundaries. Ten vertical electric soundings (VESs) are measured and used in this study to construct four geoelectrical cross-sections. According to the results, Gara's commonly calculated subsurface resistivity model comprises six major resistivity layers. The 5th layer, in particular, is composed of Fractured dolomitic Limestone and represents a possible promising shallow aquifer. Moreover, as evidenced by various magnetic data filters, the shallow (Miocene carbonate) and deep (Nubian sandstone) aquifers are structurally controlled and regulated by a system of faults or contacts. These contacts trends NW–SE, E–W, and NE–SW as common trends emerged from the total derivative and tilt maps. Results suggest that the central part (N–S zone) together with the western side of Gara, have the most notable aquifer possibility demanded future improvement strategies.

Water as property: Contention between indigenous communities and the lithium industry for water rights in Chile

AbstractWith the growing demand for lithium to be used in many electronic devices and vehicles, companies in Chile's Atacama Desert race to extract this “white gold.” Lithium mining is a water‐intensive process, seemingly impossible to sustain in the world's driest desert. Local indigenous communities rely on what little water access exists, but water becomes the property of whoever owns the land. Thus, we see growing contention between local communities and mining companies for the use of water. This study examines the intersection between communities, the environment, and lithium‐mining companies, using a political‐ecology model to understand the nuances involved in extracting this in‐demand resource. Based on interviews, news archives, and other methods, the findings indicate a need for increased trust between populations and companies. Additionally, regulatory and legal clarity and consolidation would help manage the conflicts. Activism and company and government responses can facilitate better negotiations between stakeholders and allow for access to lithium while better protecting the environment and the people that survive in the desert.

Empirical research on sustainable developmental goals and priorities for water sustainability in Saudi Arabia.

Saudi Arabia is dry and devoid of permanent water sources. Saudi Arabia's desalination plants, which provide drinkable water, rely on its oil reserves. It is one of the world's driest countries, but its population uses fresh water at a third rate. Therefore, the most crucial step is to alter people's behavior by using water more efficiently and intelligently by adopting water conservation techniques. Through adopting a strategic water strategy, the Saudi government has simplified the regulatory system in the water sector. It examines the most effective ways to generate and control water through its water policy. This research aims to forecast the water consumption required for different sectors until 2030 in Saudi Arabia and designed an intelligent Water Resource Demand Forecasting (iWRDF) model. This model used the internet of things (IoT) and big data analytics (BDA) in demand forecasting. The experimental outcomes outperform the proposed model with an accuracy of 96.86% than the existing models. Furthermore, this model helps find sustainable developmental goals and priorities for water sustainability in Saudi Arabia.

Nasca Domestic Culture: the Significance of Past Environments for Reading the Material Culture of the South Coast of Peru

Past environments of the south coast of Peru were significantly different from those prevailing today. Here, in one of the world's driest deserts, life flourished, as it does today, in riverine oases along the watercourses rising in the Andean hinterlands; and in ephemeral fog oases (lomas) along the littoral. These habitats were the foundation of agricultural and other adaptations that evolved here over millennia. In this paper we aim to reconstruct those past habitats and the huerta farms and orchards set amidst shady old-growth woodlands since these are the contexts in which we might hope to understand the sacred artistic canons of Paracas and Early Intermediate Period Nasca. We invoke the concept of “Nasca domestic nature” to reflect the continuum between wild and cultivated, resources and environments, observed empirically in traditional huerta farming and the archaeobotanical record, and also depicted with such wonderful fidelity in this iconographic canon.

Reaction of winter wheat and barley cultivars to Fusarium pseudograminearum‐inoculated fields in the dryland Pacific Northwest, USA

AbstractFusarium crown rot (FCR) of winter wheat (Triticum aestivum L.), caused by Fusarium pseudograminearm and Fusarium culmorum, is a yield‐limiting disease in arid wheat‐producing areas of the inland Pacific Northwest. Foliar fungicide applications and currently available seed treatments do not control FCR. Alternative crops that provide a rotational benefit to reduce disease are not economically feasible. Major‐gene resistance is unavailable, but there is preliminary evidence that some wheat and barley (Hordeum vulgare L.) cultivars are more resistant than others. We followed up on preliminary work by growing 14 varieties of winter wheat, planted with in‐furrow FCR inoculum, in 2018 and 2019 in Morrow County, Oregon—one of the world's driest wheat producing regions. Two barley cultivars were added to the experiment during the second year of research. Evaluations of cultivar resistance were made by conducting aboveground visual assessments by counting whiteheads, prematurely senesced wheat heads that are indicative of FCR infection. Whitehead count information was correlated with yield and grain volume weight data. Maximum whitehead counts were measured in plots of the FCR‐susceptible check cultivar ‘Stephens’. There was no evidence of a cultivar‐specific relationship between whitehead count and corresponding values for yield and grain volume weight. There was limited evidence that some cultivars have the capacity to compensate for effects of disease.

Strengthening mycorrhizal research in South America.

Strengthening mycorrhizal research in South America.

The archaeology and ethnoarchaeology of rain-fed cultivation in arid and hyper-arid North Africa

Abstract

The observed cooling effect of desert blooms based on high‐resolution Moderate Resolution Imaging Spectroradiometer products

AbstractDesert greening through planting or irrigation is a potential approach to mitigate desertification and climate warming, but its influence on regional climate is unclear due to scarcity of observations. “Desert blooms,” which are natural phenomena usually associated with the El Niño–Southern Oscillation, regularly occur in the world's driest desert, the Atacama Desert. This sudden conversion of land cover likely has a large impact on regional climate through alteration of local energy budgets and provides a unique opportunity to study the potential climatic and environmental consequences of desert greening. Here we evaluated the land surface effects of blooms in the Atacama Desert using vegetation and climate data acquired from remote sensing. The rapid vegetation growth during blooms led to an increase in evapotranspiration and a decrease in albedo. These two processes caused a 0.31°C ± 0.05°C decrease in daytime land surface temperature. During nighttime, we observed a 0.02°C ± 0.02°C increase in land surface temperature due to enhanced heat capacity associated with blooms. This asymmetric diurnal variation in land surface temperature produced a net decrease in daily land surface temperature of 0.29°C ± 0.07°C. Our observations demonstrate the potential benefits of desert blooms on local climate. Results from this study also provide new evidence for plausible climate consequences expected from local “desert greening” strategies.

Winds of Change: Controlling blowing dust in world's driest wheat‐growing region

Winds of Change: Controlling blowing dust in world's driest wheat‐growing region

Best Management Practices for Summer Fallow in the World's Driest Rainfed Wheat Region

CSA NewsVolume 59, Issue 10 p. 12-12 Science Best Management Practices for Summer Fallow in the World's Driest Rainfed Wheat Region First published: 07 October 2014 https://doi.org/10.2134/csa2014-59-10-2Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume59, Issue10October 2014Pages 12-12 RelatedInformation

Best Management Practices for Summer Fallow in the World's Driest Rainfed Wheat Region

The Horse Heaven Hills (HHH) located in south‐central Washington contains the world's driest rainfed wheat (Triticum aestivum L.) production region, where farms receive as little as 150 mm average annual precipitation. Late summer establishment of winter wheat into carryover seed‐zone water after a year of fallow is essential to achieve the highest grain yield potential. Tillage of fallow land during the spring is considered necessary to retain adequate seed‐zone water during the dry summer months, but blowing dust from excessively tilled fallow is a major safety, environmental, and soil‐quality concern. We compared three fallow management systems for soil water dynamics, wheat stand establishment, grain yield, and economic returns on two farms over 5 yr in western and eastern portions of the HHH where long‐term annual precipitation averages 153 and 211 mm, respectively. Treatments were: (i) traditional tillage (TTF), undercutter conservation tillage (UTF), and no‐till (NTF). Late‐summer planting of winter wheat in TTF and UTF was possible in only 1 of 5 yr at the western site due to lack of adequate seed‐zone water, whereas late‐summer planting was possible every year at the eastern site. There were no significant differences in net economic returns among fallow management treatments at the western site; however, net returns per hectare averaged a positive US$101 for TTF and UFT vs. a negative US$92 for NTF at the eastern site. Although seed‐zone water in late summer was consistently lowest with NTF at both sites, we recommend NTF in the western HHH because achieving adequate seed‐zone water for early wheat establishment is generally not possible with any fallow management practice and NTF is economically viable and excellent for wind erosion control. On the other hand, in the eastern HHH, where adequate seed‐zone water for early planting can be achieved with tillage most years, farmers should practice UTF. This study documented that NTF in the western HHH and UTF in the eastern HHH are best management practices for farmers and the environment in a region where wind erosion from excessively tilled soils is a severe problem.

Wind erosion and PM10 emission affected by tillage systems in the world's driest rainfed wheat region

The Horse Heaven Hills of south-central Washington is the driest rainfed wheat growing region in the world. Low precipitation, high winds, poorly aggregated soils, sparse residue cover, and a tillage-based winter wheat (Triticum aestivum L.) – summer fallow (WW-SF) cropping system often combine to create soil surfaces which are susceptible to wind erosion. No-tillage summer fallow (NTF) and conservation tillage fallow (CTF) with an undercutter sweep implement were examined as alternative practices to traditional tillage fallow (TTF) with a tandem disk implement for reducing wind erosion and PM10 (particulate matter ≤10μm in aerodynamic diameter) emissions during the fallow phase of the WW-SF rotation. Wind erosion and PM10 emissions were assessed with a wind tunnel after primary spring tillage in mid-to-late April and after sowing winter wheat in August. Sediment loss and PM10 vertical flux and loss were generally less for NTF than with TTF, likely due to retention of surface residue and maintaining a soil crust in NTF. Sediment and PM10 loss increased after sowing wheat in both the TTF and CTF treatments. Although NTF abated the loss of sediment and PM0 compared with TTF, NTF is not yet an economical option for most growers in the region. Conservation tillage fallow using the undercutter sweep is an economically viable alternative to TTF for reducing windblown sediment and PM10 loss from agricultural soils in the Horse Heaven Hills.

Predicting seed-zone water content for summer fallow in the Inland Pacific Northwest, USA

The Horse Heaven Hills in south-central Washington contains the world's driest rainfed wheat ( Triticum aestivum L.) region. The climate is Mediterranean with average annual precipitation as low as 150 mm. The cropping system is winter wheat-summer fallow. Tillage is used in the spring of the 13-month fallow to establish a dry soil mulch to help retain seed-zone water to establish winter wheat planted deep into fallow in late August. However, the Horse Heaven Hills is often so dry that even tillage-based summer fallow (TF) cannot retain adequate seed-zone water, and farmers must then wait until the onset of rains in mid October or later for planting. In such dry years, farmers would be better off practicing no-till fallow (NTF) to protect the soil from wind erosion; but no predictive tools are available to assist in these decisions. The objectives of our study were (1) to predict seed-zone water contents and water potentials in late August or early September based on soil water content measured in early April and (2) to compare seed-zone water in TF and NTF. Experiments were conducted for 5 years at each of two sites. Soil water content was measured in both early April and late August. Soil properties and residue loads were characterized to calibrate the Simultaneous Heat and Water model (SHAW). Seed-zone water was simulated in late August based on measured soil water contents in early April and measured temperature and precipitation from April to August. The SHAW model correctly predicted seed-zone water content 80% of the time. The amount and timing of rainfall occurring in April, May, and June was the most important factor controlling the seed-zone water content in late August, suggesting that farmers should delay their decision on whether to practice TF or NTF until late in the spring.

Drylands in the Earth System

A study of one of the world's driest forests elucidates the climatic effects of drylands.

A brief review of desalination in Australia in 2010

Recent climate changes and population growth throughout Australia have highlighted the need for more diverse and climate-independent water sources. Australia is the world's driest inhabited continent and the unpredictable climate means that the Australian population generally requires up to five times the water storage than does an equivalent population in the UK. Although 85% of its people live within 50 km of the coast, the country has only begun to consider large-scale seawater desalination within the past five years (Crisp, 2009). The total potable and industrial water consumption in Australia is around 50,000 ML/d (Hoang, 2009). In 2008, the total volume of water desalinated for potable and industrial use was about 0.6% (300 ML/d) and this is expected to increase more than seven times to 4% by 2013. A brief review of current (2010) desalination capacity in Australia follows and includes major seawater plants, brackish water and wastewater reuse.

Cyanobacterial ecology across environmental gradients and spatial scales in China's hot and cold deserts

Lithic photoautotrophic communities function as principal primary producers in the world's driest deserts, yet many aspects of their ecology remain unknown. This is particularly true for Asia, where some of the Earth's oldest and driest deserts occur. Using methods derived from plant landscape ecology, we measured the abundance and spatial distribution of cyanobacterial colonization on quartz stony pavement across environmental gradients of rainfall and temperature in the isolated Taklimakan and Qaidam Basin deserts of western China. Colonization within available habitat ranged from 0.37+/-0.16% to 12.6+/-1.8%, with cold dry desert sites exhibiting the lowest abundance. Variation between sites was most strongly correlated with moisture-related variables and was independent of substrate availability. Cyanobacterial communities were spatially aggregated at multiple scales in patterns distinct from the underlying rock pattern. Site-level differences in cyanobacterial spatial pattern (e.g. mean inter-patch distance) were linked with rainfall, whereas patchiness within sites was correlated with local geology (greater colonization frequency of large rocks) and biology (dispersal during rainfall). We suggest that cyanobacterial patchiness may also in part be self-organized - that is, an outcome of soil water-biological feedbacks. We propose that landscape ecology concepts and models linking desert vegetation, biological feedbacks and ecohydrological processes are applicable to microbial communities.

A study into the export of saline water from Hervey Bay, Australia

Australia's climate is one of the world's driest and locally characterised by high year-to-year rainfall variability. Due to high evaporation and low river runoff many estuaries and embayments in the region are characterised by inverse conditions with salinity increasing toward the coast and river mouths. Such conditions were also found during the first comprehensive hydrographic survey of Hervey Bay located at the east coast of Australia in early spring 2004. The survey traced a subsurface salinity maximum that was found in earlier studies within the East Australia Current, east of Hervey Bay to the shallow southwest regions of the bay. These are identified as the most likely source region for locally produced saline Hervey Bay Water. Utilising a simple box model, mean evaporation rates and historical river runoff data, it is demonstrated that inverse conditions are likely to dominate throughout the year. The negative circulation is a climatological feature of this estuary that is not limited to the dry season of the year. Due to persistent drought and declining rainfall in coastal eastern Australia, these conditions are likely to persist into the near future and need to be considered in coastal management strategies.

Cropping Systems Research in the World's Driest Rainfed Wheat Region

Winter wheat (Triticum aestivum L.)–summer fallow (WW‐SF) is the predominant cropping system in the 120000‐ha Horse Heaven Hills (HHH) region in south‐central Washington, USA. Blowing dust from residue‐ and roughness‐deficient SF results in soil loss and causes health problems. Annual no‐till cropping to replace SF would provide year‐round protection against wind erosion. A 6‐yr field study was conducted from 1996 to 2002 to evaluate the agronomic and economic feasibility of continuous annual no‐till hard red spring wheat (HRSW) as an alternative to traditional WW‐SF. Long‐term average annual precipitation at the experiment site is 152 mm, which we believe is the lowest for any nonirrigated wheat region of the world. Annual precipitation during the study ranged from 111 to 240 mm and averaged 153 mm, with two wet years followed by a 4‐yr drought. Russian thistle (Salsola iberica Sennen and Pau) heavily infested HRSW plots and depleted soil water during the two wet years. Seed‐zone water content in SF was sufficient to plant WW in late August in only 2 of 6 yr. Mean (6‐yr) grain yield was 1190 kg ha−1 for WW‐SF (one crop every 2 yr) and 530 kg ha−1 for annual no‐till HRSW. The number of kernels per spike had a significant contribution to yield during years of acute water stress. Net economic returns for annual HRSW lagged WW‐SF by an average $95 ha−1 yr−1. Although continuous annual no‐till cropping has clear environmental advantages, it is not economically competitive with WW‐SF with current technology in the HHH.