Desert Highway Research Articles

Optimal design of sizing and allocations for highway electric vehicle charging stations based on a PV system

The world’s demand for fossil fuels has recently increased significantly for both transportation and electric power generating sectors. Using these resources not only results in high costs and depletion of them but also increases greenhouse gas emissions and pollution. The electric vehicle (EV) market is growing globally, aiming to face climate change due to greenhouse gas (GHG) emissions and to reduce reliance on fossil fuels. However, the long charging time of EVs and the shortage of charging outlets limits the global adoption of EVs, especially on highways where the problem of accessibility to the electricity distribution grid appears. These issues can be faced by the good planning of charging infrastructure. However, this planning is a multidisciplinary field that includes electricity generation, transportation networks, EVs’ characteristics, and driver behavior. A methodology to provide the optimal locations and sizing of electric vehicle charging stations with their own electricity generation and storage using photovoltaic (PV) and energy storage systems on highways considering different factors is proposed in this paper. This paper takes a section of the western desert highway in Egypt connecting Assiut and Cairo cities as a case study. Four scenarios are proposed for the design of EV charging stations’ locations and sizing which are centralized charging stations, two-way charging stations, utilizing oil stations’ locations, and distributed fixed sizing charging points with a comparison between them. The work also discusses the potential effects of highway slope, wind speed, and number of passengers on the location problem. The results can be used to optimize the design of EV charging stations along highways for a completely sustainable system.

Optimal sand transport roadbed geometry structure of Taklamakan Desert highway

In order to obtain the optimal geometric structure for sand transport in desert roads, this study fully utilizes the natural sand transport capacity of the desert roads, aiming to reduce occurrences of road damage due to sand burial. The research integrates Computational Fluid Dynamics (CFD) with optimization analysis theory. Various typical geometric structures of desert highway roadbed were modeled using the Design Exploration module in CFD. Optimization analysis methods were employed to model and compute the sediment transport optimization design on both the roadbed and road surface. Then, the initial sample points are obtained by using the Design of Experiments (DOE), and the response surface is established by using the Kriging model to obtain the change trend of the input parameters and the objective function. Finally, the cross-section parameters of the sediment transport subgrade corresponding to different inflow conditions are obtained. The results show that the sediment transport performance of embankment, cutting and semi-filled uphill subgrade is negatively correlated with the height of subgrade. The relationship between slope gradient and sediment transport performance of subgrade depends on the height of subgrade and the type of subgrade section. For embankment and cutting, when the subgrade height is less than 0.5 m, the sediment transport performance of the subgrade is positively correlated with the subgrade slope; however, when the subgrade height exceeds 0.5 m, the sediment transport performance is negatively correlated with the subgrade slope. For the semi-filled uphill flow subgrade, the sediment transport performance of the subgrade is negatively correlated with the subgrade slope. Comprehensive analysis shows that semi-filled and excavated downhill subgrade has the best sand transport performance, embankment subgrade has the second highest sand transport capacity, then cutting subgrades, while semi-filled and excavated uphill subgrade has the worst sand transport performance. The research conclusions provide valuable scientific guidance for the design of sand control embankment structures tailored to local conditions for desert highways. This is of significant importance for enhancing the sediment transport capacity of desert highways and prolonging their service life.

Evaluation of Soil Quality and Analysis of Barriers of Protection Forests along Tarim Desert Highway Based on a Minimum Data Set

To gain a thorough grasp of the soil quality conditions in the preservation forests along the Tarim Desert Highway, a detailed assessment of the research area’s soil quality is necessary, along with the identification of any potential obstacles. This evaluation should identify any potential obstacles and provide a theoretical basis for the sustainable utilization and precise management of protection forest soils. This paper examines the protection forest along the Tarim Desert Highway as the study area. To characterize the features of the soil quality, thirteen indicators of the chemical, physical, and biological composition of the soil were examined. The principal component analysis method was used to construct the minimum dataset (MDS) for soil quality evaluation. The diagnostic model for obstacle factors was combined with the MDS to explore the soil quality characteristics and obstacle factors in the study region. The findings indicated that (1) the constructed indexes of the MDS of protection forest soil in the study area included soil ammonium nitrogen (NH4+-N); quick-acting phosphorus (AvP); organic carbon (SOC); alkaline phosphatase (AP); and total salt (SS); (2) soil quality based on the MDS and the total dataset (TDS) showed a significant positive correlation (R2 = 0.748; p < 0.05), and the research region’s soil quality were all in the medium and below level (100% of SQI ≤ 0.6), showing the status quo of high soil quality in the two ends of the shelterbelt forest and the tower center area, while the other areas were relatively low; (3) according to the findings of the soil barrier analysis, the two main obstacles influencing the soil quality of the shelterbelt forest at this time are NH4+-N and SOC, and that the soil quality of the shelterbelt forest could be improved by artificially increasing the inputs of nutrients and precise conservation measures, promoting the overall function of artificial protective forests on desert highways. In addition to providing a solid scientific foundation for the sustainable use and maintenance of shelterbelt forests along the Tarim Desert Highway, this study is also an invaluable resource for researching the soil quality of artificial shelterbelt forests in arid regions.

Heterorhabditis alii n. sp. (Nematoda: Heterorhabditidae), a novel entomopathogenic nematode from Egypt used against the fall armyworm, Spodoptera frugiperda (Smith 1797) (Lepidoptera: Noctuidae)

BackgroundIsolation of novel species of entomopathogenic nematodes (EPNs) with biocontrol potential against important insect pests is very important for the sustainable management of economic pests damaging food crops and providing protection to the agricultural environment. This study was aimed to new indigenous EPN isolates from Egyptian agricultural soils and studies its biocontrol potential for further use in the biological control programs. Five out of 15 soil samples obtained from a farm located at the Cairo–Alexandria desert highway was positive for the presence of EPN, using the greater wax moth baiting method.ResultsSequencing of the internal transcribed spacer (ITS) region of 4 of the nematode isolates suggested that they belong to the species Heterorhabditis indica. However, one isolate does not show a high similarity to any of the H. indica previously recorded in the database of the Gen Bank and hence was identified as a new Heterorhabditis species and was deposited at the National Center for Biotechnology Information (NCBI) and registered under accession no. (OP555450) under the name of Heterorhabditis alii. This new species was also registered in the ZooBank under the registration link of: LSID urn: lsid: zoobank.org: act: 306F9D57-CC30-4B8E-8B19-4F0E42B08F34. No males were found in this species. Morphological characterization using the light microscope (LM) and scanning electron microscope (SEM) confirmed the identification of this nematode as a new species of the genus Heterorhabditis. Moreover, virulence of this new species against the fall armyworm (FAW), Spodoptera frugiperda (Smith 1797) (Lepidoptera: Noctuidae) was tested in comparison with the foreign EPN species, Heterorhabditis bacteriophora (HP88) and the local Heterorhabditis indica (Mango 2 isolate) and proved to be more effective against this devastative insect pest than the two compared species.ConclusionsThe present study found out a new species of the EPN genus, Heterorhabditis in Egypt. Our results were confirmed by both morphological and molecular analyses. The efficacy of this new species against the FAW proved to be a potent and safe biocontrol agent that can be used in biological control programs against this invasive insect pest of corn in Egypt and other global countries.

Feasibility analysis of hybrid energy generation systems for desert highway service areas: a case study in northern Xinjiang, China

Highways consume a significant amount of electrical energy annually, especially in remote desert regions where the cost of electricity is high. This research explores the utilization of natural resources along desert highways to establish hybrid energy generation systems for service areas. Three service areas along the desert highway in northern Xinjiang, China, serve as case studies. To assess the feasibility of hybrid energy generation systems in these service areas, meteorological data for the three locations were obtained from the NASA platform. The HOMER Pro software was employed for technical, economic, and environmental analyses of the systems. The results indicate the feasibility of Photovoltaic (PV)/Wind/Battery hybrid energy systems in the Huanghuagou, Kelameili, and Wujiaqu service areas. The application of these hybrid energy generation systems across the three service areas could provide 3,349,557 kWh of electrical energy annually for the desert highway. Sensitivity analysis reveals that the Net Present Cost (NPC) and Cost of Energy (COE) values decrease with increasing radiation levels, while NPC shows an increasing trend with growing load demand, and COE exhibits a decreasing trend. Among the three regions, Wujiaqu demonstrates the highest economic viability, with a COE of $0.34/kWh and an NPC of $3,141,641/kWh. Furthermore, Wujiaqu exhibits the lowest environmental impact, with CO2 emissions of 198,387 kg/yr, SO2 emissions of 493 kg/yr, and NOx emissions of 1,711 kg/yr.

Evaluating the Stand Structure, Carbon Sequestration, Oxygen Release Function, and Carbon Sink Value of Three Artificial Shrubs alongside the Tarim Desert Highway

Currently, the ecological problems caused by the greenhouse effect are growing more serious, and implementing carbon sequestration methods is an effective way to address them. Arid and semi-arid desert areas have tremendous potential as carbon sinks, and artificial forests in these areas play an important role in absorbing and sequestering carbon dioxide. This study selected three main species of artificial protective trees along the Tarim Desert Highway—Haloxylon ammodendron (C.A.Mey.) Bunge, Calligonum mongolicum Turcz. and Tamarix chinensis Lour.—and evaluated them for their carbon sequestration, oxygen release capacity, and economic benefits using Pn (net photosynthetic rate) and biomass methods. The results showed that the average daily Pn value and carbon sequestration and oxygen release per unit leaf area of T. chinensis were significantly higher than those of H. ammodendron and C. mongolicum (p < 0.05). The total carbon storage of the three shelterbelts was 15.41 × 104 t, and the carbon storage of H. ammodendron was significantly higher than that of C. mongolicum and T. chinensis (p < 0.05). According to the net photosynthetic rate method, the annual carbon sequestration and oxygen release of the shelter forest is 6.13 × 104 t a−1, and the transaction price is CNY 13.73 million a−1. The total amount of carbon sequestration and oxygen release of the shelter forest obtained via the biomass method is 97.61 × 104 t, and the transaction price is CNY 218.77 million. This study conducted research on the carbon sequestration capacity of protective forests along the Tarim Desert Highway located in an extremely arid region. It highlights the significant contribution of these protective forests in terms of carbon storage, playing a crucial role in promoting ecological restoration and sustainable development in arid areas. Additionally, this study provides a scientific basis for estimating carbon storage and promoting the sustainable management of artificial forests in arid desert regions.

Sap flow of two typical woody halophyte species responding to the meteorological and irrigation water conditions in Taklimakan Desert

Understanding plant water consumption is crucial for artificial afforestation under drought environments and water stress in desert regions. However, the water consumption characteristics of desert species responding to the irrigation regimes are often neglected. By conducting a field test in the Taklimakan Desert Highway shelterbelt, this study examines the sap flow traits of two typical woody halophyte species (Calligonum mongolicum and Haloxylon ammodendron) and how they react to weather conditions and watering practices. Under the same irrigation treatment, the stem flux of C. mongolicum on sunny days was 1.5–5.3 times that on dusty days, while the stem flux of H. ammodendron on sunny days was 3.5–5.5 times that on dusty days. Both species demonstrated some sap flow during the night, representing 14.3%–24.9% and 7.3%–10.4% of the total sap flow for C. mongolicum and H. ammodendron, respectively. H. ammodendron maintained a higher stem flow during daytime and was more drought resistant than C. mongolicum. The daily sap flow patterns of these two species varied, showing both ‘single’ and ‘double peak’ curves depending on the watering conditions. A delay was also observed between the sap flow of these two species and the environmental factors. The factors influencing plant sap flow were found to be in the order of solar radiation, temperature, relative humidity, and saturated water vapor pressure difference. A BP-neural network proved highly effective for accurately simulating the sap flow of these two species. This research provides insights into how two common desert tree species adapt their water use in response to drought conditions, which is vital for artificial forest creation in desert areas.

Road Accident Hotspots on Jordan’s Highway Based on Geometric Designs Using Structural Equation Modeling

One of the primary objectives of transportation engineering is to increase the safety of road infrastructure. This study seeks to determine the relationship between geometric design parameters in relation to road accident criteria based on accident hotspots on Jordan’s Desert Highway. The road accident data (from 2016 to 2019) were collected from the Jordan Traffic Department. The spatial pattern of hotspots was identified using a GIS tool named Getis-Ord Gi* based on the severity index of road accidents. A topographic survey was conducted to investigate the road alignment and intersections at hotspot locations. The study utilized the Structural Equation Modeling (SEM) technique via SmartPLS to highlight the correlation between geometric designs in relation to road accidents. The hotspot analysis (Gits-Ord Gi) discovered 80 road accident hotspots along the highway. The study found that horizontal alignment and road intersections significantly impact road accidents in hotspot locations. Furthermore, vertical alignment has no effect on road accidents in hotspot areas. The study enhanced the comprehension of the factors associated with road geometrics and intersections that affect the occurrence of road accidents.

Assessment of sand accumulation hazard on desert highway based on variable weight-cloud model theory

The accumulation of sand on desert roads poses a significant threat to the smooth transportation and driving safety of these roads. To address this issue, a combined approach using the variable weight theory and cloud model theory is proposed for conducting a safety risk assessment of sand accumulation on desert roads. An evaluation index system for sand accumulation hazards is obtained through the analysis of regional geomorphological conditions, wind dynamic conditions, and engineering design factors. The evaluation index system’s constant weights are determined using the Five-Point Scale Method and Analytic Hierarchy Process. Moreover, the Variable Weight Theory is used to optimize these weights based on the actual state of the project, thereby enhancing the accuracy of risk assessment. Finally, based on the cloud model theory, a safety risk assessment model is constructed for sand accumulation hazards on desert highways. The sand accumulation hazard level of the highway is determined through this model, and the comprehensive evaluation results are visualized and presented intuitively using the MATLAB software. The experimental section of the new Wuhai-Maqin expressway sand prevention test is taken as an example for practical verification. The results show that the sand accumulation disaster level of the experimental section is grade Ⅲ, which is basically consistent with the actual engineering situation, verifying the reliability and applicability of the model. Therefore, this model could serve as an essential reference for risk assessments of sand accumulation hazards, location optimization selection, and the establishment of effective sand prevention engineering measures for desert highways.

Field Characterization of Dynamic Response of Geocell-Reinforced Aeolian Sand Subgrade under Live Traffic

In desert regions, aeolian sand is abundant, but it is not suitable to be used directly as the upper roadbed filler for highways. Generally, gravelly soil is mined around the desert as upper roadbed fill, resulting in high engineering expenses for road construction in the desert hinterland. Geocells have a significant reinforcing effect on aeolian sand. However, in the completed desert highway, the dynamic performance of geocell-reinforced aeolian sand as an upper layer of roadbed fill has not been studied. Using a field test method, the dynamic performance of geocell-reinforced aeolian sand as an upper roadbed fill is examined. The results show that the majority of the frequency distribution of road vibration is within 30 Hz. In the horizontal direction, the actual vibration amplitude decay on the side of geocell-reinforced aeolian sand is slower but smoother than on the side of gravelly soils. In vibration velocity, the work area depth of the geocell-reinforced aeolian sand side of the roadbed is less than that of the gravelly soil side. The maximum difference can reach 0.55 m. As far as vibration velocity is concerned, the 30 cm gravelly soils can be substituted with 15 cm geocell-reinforced aeolian sands as the upper roadbed. In summary, the dynamic attenuation characteristics of geocell-reinforced aeolian sand are superior to gravelly soils. The research results provide a reference for the design of the desert highway subgrade.

Study on Sand-Accumulation Changes of Highway and Formation Mechanism of Sand Damage in Drifting Dunes Areas

After the construction of desert highway, the physiognomy changes caused by surface wind erosion and accumulation not only seriously threaten the stability of road structure, but also have a tremendous impact on the safety of the highway operation and the maintenance work on the highway. The purpose of this paper is to explore the change of sand sedimentation and the law of sand transport along the highway in the moving dune areas, and to clarify the change of sand flow and the formation mechanism of sand damage in the moving dune areas. Taking the test section of Wuhai-Maqin Expressway in the hinterland of Tengger Desert as the research object, the on-site observation of sand accumulation and the recording of wind information by small weather stations were adopted, supplemented by CFD numerical simulation method, in order to provide reference for the construction of sand control system in moving dune areas. The study results show that: (1) Dunes not only obstruct wind-drift sand but are also the sediment source condition for forming road sand. The windward dunes near the road are affected by wind and the deposition of sand will quickly bury the road in the strong wind season. (2) Compared with highways with flat terrain, the existence of dunes affects the flow field structure and the distribution of sand sedimentation on the highway, in which, under the influence of the gathering effect, the flow velocity reaches the maximum at the top of the dune and a large low-speed recirculation zone is formed on the lee side of the dune, easily causing sand accumulation. (3) Sediment accumulates at the windward side of the embankment or dune where sandy air current is easy to saturate. However, with the increase of wind speed, in addition to the grit carried by the sandy air current itself, new sand rolled up on the windward side of the dunes also form deposits on the road surface and the amount of sand-accumulation on highway surface and leeward side tends to increase. As a result, for the highway in drifting sand dunes areas, sediment prevention and control measures should be taken actively. It is necessary to remove sediment from the road in time and reduce the moving speed of sand dunes and the deposition range of wind-sand flow, ultimately for the purpose of reducing the damage wind-sand activity causes to the highway in desert.

Numerical Simulation Research on Plane Alignment Parameters of Desert Highway

Using the plane alignment design of the Wuhai–Maqin highway as the background of this study, based on the Fluent–Euler two-fluid model, the response law of the wind–sand flow to the embankment under different angles, different curve radii, and different surface windward factors were studied. Additionally, the accuracy of the numerical simulation was verified by the distribution of sand accumulation on the embankment site. The results show that when the wind–sand flow passes through the embankment, and when the angle between the wind direction and the straight embankment gradually decreases from 90° (vertical) to 0° (parallel), the speed-division range is correspondingly shortened. Under the influence of plane alignment, the diversion effect leads to a certain difference in the flow-field structure at different positions of the line. The convex windward embankment has the effect of dredging the wind–sand flow outward. The concave windward embankment has the effect of gathering the wind–sand flow inward. The dredging and gathering effects of the flat curve on the wind–sand flow decreases with the increase in the radius. In the plane linear design, line direction should be parallel to the dominant wind direction as much as possible. If a flat curve needs to be set, the convex windward curve should be given priority, and a large radius curve should be selected as much as possible.

Optimal flood susceptibility model based on performance comparisons of LR, EGB, and RF algorithms

Wadi El-Matulla, located in the eastern desert of Egypt, is the most important water basin. The Qift–Qusayr highway (west–east direction) and the Cairo–Aswan eastern desert highway (north–south direction) pass through the watershed. Many urban areas (villages and industrial areas) and agricultural lands are located at the outlet of these basins. In addition, the basin has promising potential for future economic and urban development as it is located within the Golden Triangle (governmental megaproject). The current study investigates flood hazard modeling and its impact on the area. To determine the optimal flood susceptibility mapping algorithm, performance comparisons of three techniques were conducted: logistic regression (LR), extreme gradient boosting (EGB), and random forest (RF). Remote sensing, topographic, geologic, and meteorological data were used with the help of field visits to provide the spatial and inventory database required by the models. The performance and reliability of the predictions of the proposed models were evaluated using five statistical indices: receiver operating characteristic–area under the curve, overall accuracy (OAC), kappa index, root mean square error (RMSE), and mean absolute error (MAE). The performance of the models showed that the values of ROC (93, 86 and 80%), OAC (88, 82 and 76%), kappa index (0.85, 0.75 and 0.51), RMSE (0.34, 0.42 and 0.49) and MAE (0.12, 0.18 and 0.24) for RF, EGB, and LR, respectively. Based on AUC values, RF and EGB models provide excellent and very good prediction for flood susceptibility. Our results show that RF is the optimal algorithm for flood susceptibility mapping, followed by EGB and LR. Consequently, the predictive power of RF model is quite good and the flood susceptibility map was classified into five classes, namely very low (51.7%), low (23.7%), moderate (16.2%), high (7.1%), and very high (1.3%). Ultimately, the RF model was verified using sentinel-1 imagery for real floods in 2016 and 2021, and it provides good agreement. The optimal model could be useful for decision makers and planners to protect existing facilities and plan future projects in non-flood-prone areas. Accordingly, the most suitable areas for future development need to be distributed mainly in the low and very low flood hazard areas.

Microplastic Contamination in Urban, Farmland and Desert Environments along a Highway in Southern Xinjiang, China.

The different types of microplastics (MPs), including debris, fibers, particles, foams, films and others, have become a global environmental problem. However, there is still a lack of research and understanding of the pollution characteristics and main causes of MPs in the arid region of Xinjiang, China. In this survey, we focused on the occurrence and distribution of MPs in urban, farmland and desert areas along a highway in the survey area. Our results showed that the main types of MPs were polypropylene (PP) flakes, polyethylene (PE) films and both PE and PP fragments and fibers. The abundance levels of MPs in street dust of Korla, Alar and Hotan districts equaled 804, 307 and 1526 particles kg−1, respectively, and were positively correlated with the urban population. In farmland areas, there were only two types of MPs (films and fibers), of which the film particles dominated and accounted for 91% of the total on the average. The highest abundance rate of MPs reached 7292 particles kg−1 in the desert area along the highway. The minimum microplastic particle sizes were 51.8 ± 2.2 μm in urban street dust samples, 54.2 ± 5.3 μm in farmland soil samples and 67.8 ± 8.4 μm in samples from along the desert highway. Particle sizes < 500 μm were most common and accounted for 48–91% of the total in our survey. The abundance and shape distribution of the MPs were closely related to the different types of human activities.

An Artificial Oasis in a Deadly Desert: Practices and Enlightenments

Building highway and its biological protection system in a drought-affected shifting-sand desert is a great challenge. This challenge was completed by the construction of the Taklimakan Desert Highway Shelterbelt (TDHS)—the longest of its kind in the world (436 km). The TDHS can serve as a model for highway construction and desertification control using eco-friendly and cost-effective approaches in other desert regions. Notably, we proved that local saline groundwater irrigation offers potential advantages and opportunities for the growth of halophytes and sandy soil development in hyper-arid desert environments. Here, we systematically (1) summarize the project, its results, and vital technical issues of saline water irrigation; (2) address soil hydrological processes that play a crucial role in maintaining those systems; and (3) highlight useful insights for soil development, plant survival, and soil–plant–water–biota synergy mechanisms. Indeed, the TDHS project has provided a proof of concept for restoration and desert greening initiatives.

DEVELOPING PREDICTION MODELS FOR SLOPE VARIANCE FROM THE INTERNATIONAL ROUGHNESS INDEX

Road roughness is considered a primary indicator of pavement condition and serviceability, and the performance of paved roads is linked to road roughness. The focus of this study is to develop a relationship between two important roughness indicators, namely the international roughness index (IRI) and slope variance (SV), based on actual road roughness data to achieve a suitable correlation between these two indices using artificial neural networks (ANNa) and gene expression programming (GEP) techniques. Different study areas were selected to develop the prediction model. The first study area is the Desert Highway in Jordan, while the three remaining study areas are located in the US. A total of 533 data sets were used in this study to develop a model to predict the IRI from the SV. The GeneXproTools 5 software package was used to build the GEP model, while MATLAB 2019 was employed to develop the ANN model. The results showed that the GEP and ANN models outperformed all other previous models. The GEP-Based model showed a better performance and more precise results than the ANN model according to the coefficient of determination (R2).

Effects of Irrigation Regimes on Soil Water Dynamics of Two Typical Woody Halophyte Species in Taklimakan Desert Highway Shelterbelt

Freshwater resources are in a shortage in arid regions worldwide, especially in extremely arid desert areas. To solve this problem, highly saline groundwater is used for drip irrigation of desert plants. Since more irrigation infiltrating into the deep soil cannot be absorbed and utilized by desert plants, it is crucial to determine optimal water-saving irrigation regimes. In this study, we examined the effects of irrigation regimes on the soil water dynamics of two typical woody halophyte species (Haloxylon and Calligonum), and quantified the irrigation intervals and periods based on a field test of precision irrigation control in the Taklimakan Desert Highway shelterbelt. Results showed that the change in soil moisture of two species in the shallow 0–60 cm layer could be divided into a rapid decline period (1–9 d), a slow decline period (9–19 d), and a relatively stable period (19–39 d) after irrigation. The decrease rate of soil moisture at the 0–60 cm depth was significantly higher than that at the 60–200 cm depth. The irrigation regime combining 35 mm irrigation with 10 days was beneficial to soil water storage and plant use with respect to Calligonum, while the irrigation regime combining 35 mm irrigation with 40 days was best for Haloxylon. Increasing the single irrigation amount and prolonging the irrigation period can further enable the more effective use of irrigation water. This study highlights that saline groundwater irrigation provides potential advantages for desert plants’ survival under reasonable irrigation regimes.

Influence of Different Types of Guardrails on Sand Transportation by Desert Highway

Influence of Different Types of Guardrails on Sand Transportation by Desert Highway

Desert Highway Pantoum, and: The Animal, and: The Hares

Desert Highway Pantoum, and: The Animal, and: The Hares Hannah Sanghee Park (bio) Desert Highway Pantoum I drive from Point A to a pointthe highway slims to.My future is this bright aperture,this needle-eyed beyond. The highway slims toa lone lane. Gauges limit me—this need will lie beyondthe road, to the siren singalong alone. Language limits melately. I’ve lost the pulse ofthe road to the sirens signalingmove to the shoulder. I wait. Lately I’ve lost the pulsecontaining me. Later I left (cowardmove) to shoulder the weight.Grief grew long in me, containing me later. I left, cowardto chance, and the wild vining ofgrief grew along with me.How I couldn’t go back to chance, and the wild vining ofmy fear without break.How I couldn’t go backin time. Begin. Sun’s well down, low. Answers my fear. Without breakI drive from Point A to a pointin time begging, Sun, swell down slow. And swearmy future is this brighter aperture. [End Page 36] The Animal Whatever it was, went fast. Felled wetby one gunshot. The ground listenedthrough its sour mushroom ears.The kill fell spilled and they darkened alive.I hate the world too wild and yet I am here.Everything that makes me up left violently—star and hominid and warring ancestor.Taught to lunge for the throat, throttling breath,body from head, voice from thought stillshaping on the tongue. To end a thingrequires steel and every nerveto never stop. That’s the trick of it.To burn the land until every treeis turtlenecked in char, wind carryingout its worst, until the air stinks ofsomething we’ve killed and can’t stop killing.The animal was opened to the skylike a grand piano. Its maggots pumpingtheir oily bellows in hunger.And everyone rubbernecking,a slack weakness the jaw wants to crush.To lure each eye to sleep—that’s the trick—to comfort, and then the god comes down. Fast I have already forgotten what hurt me.I bow to the new like a cut flower, hangdog.In the way these animals come circling,even after they’ve seen the worst of us—blood plugging up our heads, soakedin what’s theirs. But they forget. Foot before footto salt and bait, the outstretched handsmells so good. God, that could drive a body. [End Page 37] The promise of hope over cruelty.That what feeds you has already fed.It is what moves foot before foot toward you.Somewhere my end is marked but I will notknow it. I will only know this mercy. So faster and faster I feed, unafraid.And if this is really the fittest of me,what’s fated, what survived of me—forgive me. But look: I do not flinch. I eat,believing in this that I am being loved,and fill the eyes of my body until I forget. [End Page 38] The Hares Long-eared,they had long heardof the boys: the threats of their hands: the boyswanted their pelts:the winters unkind to their kind. This wasnature: alwaysthese little wars for resources. The haresbounded from themin a wisdom. They would lope up mountains,knowing their legsat birth were strong: come spring-loaded with kickand bolt. Born withtheir eyes as open as tree rings, they sawthe boys: hobbledby the known thunder of their treads: shoutingas they tried tofollow: failing stealth. Born helpless and weak,whatever madethem human was taught over years. [End Page 39] This wasdominion: thatno mountain was greater than want: that wantwas the mission.Now older, they chased the hares but this timedown the mountains.And the hares fled: haste flustered them: their legscould not find ground:their heads, their fine backs kept rolling down landbetraying them.Then the men pounced. Dashed them until they werestill. The men wereproud: they brought back the small corpses: they braggedover the shineof their beers and...

Effect of Saline Water for Drip Irrigation on Microbial Diversity and on Fertility of Aeolian Sandy Soils

Saline water is widely distributed in the arid environment and sometimes represents the only source of irrigation water to restore and reconstruct vegetation. However, the effects of saline water on the bacterial diversity and fertility level of aeolian sandy soil are not well understood. In this study, we investigated a vegetation belt along the Tarim Desert Highway that has been constructed as a windbreak and consists of desert shrubs and was irrigated with saline water at six levels of salinity along the Tarim Desert Highway. The bacterial diversity was studied using Biolog Eco, a phospholipid fatty acid analysis, and a polymerase chain reaction–denaturing gradient gel electrophoresis, and the soil fertility was calculated and expressed as the integrated fertility index. The soil bacterial diversity (in terms of carbon metabolism, genes, and fatty acid species) was significantly affected by the level of salinity, and the microbial activity was low under high salinity. Fertility was also markedly affected by the degree of salinity and by the depth of soil, being lower at higher salinity levels and in the top layer (0–5 cm), and was also correlated to both the metabolic diversity index of soil microorganisms and the diversity index of fatty acids of soil microorganisms. The genetic diversity index of soil microorganisms shared a polynomial relation with fertility and contributed to it positively and significantly. Therefore, using less saline water for drip irrigation could avoid salt accumulation in soil and arrest its compaction, promote the formation of soil aggregates and the build-up of nutrients, and increase microbial activity, thus playing a crucial role in promoting the circulation, conversion, and utilization of nutrients in aeolian sandy soils and improving the soil quality. The judicious use of saline water, therefore, deserves serious consideration in irrigation practices.