Sand Depth Research Articles

Estimation of Submarine Cable Burial Depth using CBRA Model

Submarine cable plays an important role in land-island power supply, and domestic and overseas communication. However, damages to the submarine cable have been caused by various dangerous factors such as ship anchors and trawlers. Even though the annual cost for recovering submarine cables is enormous, there is no definite method for protecting submarine cables. The present study investigates the applicability of Cable Burial Risk Assessment (CBRA) model to the estimation of the burial depth of submarine cables. This technique employs a statistical approach to the marine environment of the target area and the navigation data of nearby passing ships. Two computer programs have been developed to facilitate the calculations of anchor penetration depths in clay and sand, respectively. An example application of CBRA model was demonstrated here taking a tentative cable route to Haenam - Jeju sea area. The cable burial depth was calculated to vary from a minimum of 0.6m to a maximum of 0.74m for a 2500 year return period and a minimum of 0.6m to a maximum of 1.40m for a 25,000 year return period. This study also determined the target ship weight in the CBRA model through the statistical expectation. The expected cable burial depth appeared from a minimum of 0.6m to a maximum of 1.26m.

Prey detection in antlions: propagation of vibrational signals deep into the sand

AbstractTrap‐building antlion larvae detect their prey according to the substrate vibrations produced during movement of the prey on the sand surface. Although most studies are devoted to surface vibrational waves, in the present study, we determine the role of vibrations travelling through deeper sand layers. A behavioural experiment confirms that vibrational stimuli from prey insects on the surface of the sand stimulate the antlions buried in deeper sand layers to move towards the surface. Sand depth and particle size both have a strong effect on signal transmission. The damping coefficient (α10) varies from 0.49 dB to 3.30 dB cm−1 and depends on frequency (in the range from 100 to 300 Hz), particle size (from finest to coarse sand) and distance from the source of the vibrations. The deeper the sand, the narrower the frequency range of the signal becomes. Sand is a filter for higher frequencies. The smaller the sand particles, the more intense the filtering becomes. Fine sand with a mean sand particle size of 360 μm is a more efficient filter than coarse sand; consequently, high frequencies (> 2.5 kHz) are eliminated at a depth of 3 cm. Mean frequency depends on both depth and particle size. However, low frequency signals still propagate at a certain distance, which is biologically important in prey detection. Although the most efficient signal propagation appears to occur in coarse sand, it contains overly large particles that are inconvenient for relatively small antlion larvae. Predators seek a compromise between fine and coarse sand choosing medium sand.

Shallow aquifer potential mapping in the foothills of Churia in Eastern Gangetic Plain of Saptari District, Nepal

The population living in the foothills of Churia, the study area, faces severe water scarcity due to limited access to surface water. The only alternative is groundwater, and there is extensive use of groundwater for domestic and agricultural purposes. Groundwater in some areas is limited and very limited information pertaining to the aquifer. In this context, this research tries to answer the pertinent questions concerning the aquifer properties, depth and thickness of the groundwater aquifer layer and groundwater prospects for irrigation. The objective of this research is to identify the aquifer properties and groundwater prospects using two-dimensional electrical resistivity tomography methods (2D-ERT). Five 2D-ERT profiles were used to collect information to a depth of around 40 m, with minimum electrode spacing of 5 m over a profile length of 240 m. The survey was carried out using Wenner electrode configurations. The resistivity tomogram sections were interpreted using RES2DINV software, which provides output in the form of resistivity contours that are used to draw up the lithological and geological information. The result of the survey indicates that the areas with good potential for groundwater access exist mostly along the southeast to central east parts of the study area, where there is gravel and sand with resistivity values between 100 and 500 Ω m. Areas along the northwest with clay and silty clay formations have low resistivity values (< 70 Ω m) and low groundwater potential. While the northeast has high resistivity values (> 2000 Ω m) due to sand formation underlain by boulder and cobbles, it also has limited groundwater potential due to the limited depth (< 6 m) of sand and low storage capacity. The study reveals a variation in lithological formation, including a patchwork of clay, silty clay, sand, gravel and boulder materials, with varying groundwater potentials. When developing shallow tube wells in the study area, spatial variation in the productive aquifer, hydraulic conductivity of groundwater flow within and near the tapped aquifer and geological and lithological material need to be considered.

Sand burial helps regulate timing of seed germination of a dominant herb in an inland dune ecosystem with a semiarid temperate climate

Sand burial plays important role in the life history of species in sandy areas of arid and semi-arid temperate regions, by affecting seed germination, seedling growth and survival and plant community. However, few studies have focused on the effects of sand burial on the dynamics of seed dormancy in such areas. In this study, seed germination characteristics of Allium tenuissimum, a dominant perennial herb in the dune ecosystem in Ordos Plateau in northern China, was investigated. Dormancy dynamics were monitored for seeds buried at sand depths of 0, 2 and 5 cm in the natural habitats for 13 months. Freshly matured seeds of A. tenuissimum were conditionally dormant and germinated to high percentages at high but not low temperatures. Germination percentages were increased by incubation at summer temperature (15/25 °C) and dry storage, but GA3 and cold stratification had no significant effects. These results suggested that seeds of A. tenuissimum were conditionally dormant, and incubation under warm, wet (but not cold, wet) conditions and dry after-ripening resulted in complete dormancy releasing. Seeds buried at 2 and 5 cm in the field for 13 months exhibited seasonal changes in germination, with an increase in spring and summer followed by decrease in autumn and winter. However, seeds on the soil surface (0 cm) gradually came out of dormancy beginning in January, and germinated percentage was highest in July, after which remained high. The peak of nondormancy for seeds buried in the field was in the summer, which corresponds to the period of highest annual precipitation. Sand burial helped mediate seeds dormancy dynamics of A. tenuissimum via seasonal dormancy cycling. Our finding contributes to a better understanding of how timing of seedling establishment is controlled in a semiarid dune ecosystem in temperate climate.

Effects of Seed Size and Sand Burial on Germination and Early Growth of Seedlings for Coastal Pinus thunbergii Parl. in the Northern Shandong Peninsula, China

This paper examines the effects of seed size and the depth of sand burial on seed germination and seedling development for Pinus thunbergii. Parl. Seeds from 20- to 30-year old trees grown in the coastal area of Yantai were divided into three size categories (large, medium, and small). The seeds were sown in pots with different depth of sand, and their germination and seedling growth during the first month were investigated. Results showed that large seeds possessed the highest 1000-seed weight and soluble sugar concentration. Large and medium seeds had a higher germination rate, germination index, vigor index, and seedling biomass than small seeds. With the increase in seed size, root mass ratio, root/shoot ratio, specific root length, and specific root area decreased, whereas leaf mass ratio increased. Sand burial depth significantly influenced seed germination and seedling growth, and the highest germination rate and seedling biomass were achieved with 2–3 cm sand burial. We also found that seedling biomass was positively related to germination rate, germination index, and vigor index, but was negatively related to mean germination time. Moreover, seedling biomass was negatively correlated with root mass ratio and root/shoot ratio, but positively correlated with leaf mass ratio, specific root length, and specific root area. The results suggest that seed size and sand burial depth are key factors in the regeneration of the coastal P. thunbergii forest.

Historical evolution and controls on mega-blowouts in northeastern Qinghai-Tibetan Plateau, China

Mega-blowouts are very large-scale deflationary landforms, formed by wind erosion. They are abundant in the Gonghe basin, northeast margin of the Qinghai-Tibet Plateau (QTP) and little is known about the evolution, dynamics or controls on the mega-blowout development. Here we report on mega-blowouts' morphodynamic expansion rates based on 4 years of monitoring. Also presented is a remotely sensed longer-term (48 years) morphologic change record which is used to understand the initiation, growth and evolution of mega-blowouts in alpine grasslands. Links between the morphodynamics and blowout-controlling factors are analysed. The expansion rates of the monitored blowouts vary according to blowout area, with different parts of the blowouts expanding at different rates. Generally longitudinal (downwind) mega-blowout expansion is greatest, with upwind headwall expansion via collapse being particularly significant. The growth of depositional lobes downwind of mega-blowouts tends to be faster than growth of the deflation basins. Merging of adjacent blowouts is one of the key mechanisms for mega-blowout development and extension. Sediment characteristics, wind erosion, water erosion, and freeze-thaw processes also all play a part in mega-blowout initiation and expansion. However, the relative roles that these factors play may differ according to a blowout's evolutionary stage. Due to an almost unlimited depth of sand, very low water table, and short grass vegetation cover, evolution into parabolic dunes is limited. A large proportion of sand patches and small blowouts around the mega-blowouts are still developing in the Gonghe basin proving that land degradation is still ongoing. Future work will focus on the feedback mechanisms between the blowout morphodynamics, climate change and anthropogenic impacts.

Bacterial filtration efficiencies and the bacterial communities’ proportions differences between sand size and depths in biosand filters

Bacterial filtration efficiencies and the bacterial communities’ proportions differences between sand size and depths in biosand filters

Sensitivity analysis in using of artificial neural network models to determine infill well locations in a mature oil field

This paper describes a method to rank potential infill well locations using Artificial Neural Networks (ANN) from existing well data. Sensitivity test was conducted for training and testing data used with comparison 2:8, 4:6, 5:5, 6:4 and 8:2 for each data. Root Mean Square Error difference between training and test data show that the best results obtained from the ratio of training data and testing data 8: 2. Two ANN models were built. The first model predicted top sand depth, resistivity, gamma-ray and density-neutron from infill well location (chosen from structural position and good oil rates from offset wells). The second model predicted initial oil rate from outputs from the first model. Predicted initial oil rates from the ANN model were compared with those from the 3D reservoir simulation model. They shows similar prediction of oil rates which gave high confidence in the predicted oil rate. Very different oil rate prediction between the two models can be used as consideration to improve the simulation model.

Assessment of Environmental Sensitivity to Desertification in Katsina State, Nigeria

Land degradation and Desertification (LDD) are critical issues facing most states in northern Nigeria, with severe consequences for national food security. Land degradation refers to total loss of the productive capacity of the soils for present and future use while desertification is seen as a process whereby the productivity of arid or semi-arid land falls by 10% or more. The Environmental Sensitivity to Desertification Index (ESDI) is the most frequently applied indicator-based system for accessing Land Degradation and Desertification. The research reported here adopted the MEDALUS (Mediterranean Desertification and Land Use) approach for identifying environmentally sensitive areas (ESA) to desertification in Katsina State, Nigeria based on Soil Quality Index (SQI), Climate Quality Index (CQI) and Vegetation Quality Index (VQI). The findings from each of these indicators show the variability between the northern and southern parts of Katsina State. The northern part of Katsina state was found to be the most vulnerable area to desertification and is covered by soil having the highest sand depth while the southern part of the state was found to be the least affected by desertification. This result specifically highlights areas in the State that requires urgent attention and remediation. Findings from this research can be used to support informed decision-making and policy development to focus on sustaining the environment, as well as the livelihood of the communities in the affected local government areas in the northern part of the State, given the high sensitivity of the area to desert conditions.

Ecological role of physical dormancy in seeds of Oxytropis racemosa in a semiarid sandland with unpredictable rainfall

Seed dormancy and the soil seed bank are crucial to plant regeneration strategy, especially in semiarid ecosystems with unpredictable precipitation. The aim of this study was to investigate how seed dormancy is controlled by environmental factors and how it is correlated with the soil seed bank and regeneration of the perennial legume Oxytropis racemosa, a dominant perennial herb in Mu Us Sandland of semiarid China. Germination and imbibition experiments on fresh intact and scarified seeds of O. racemosa were used to identify physical dormancy (PY) in seeds of this species. Soil seed bank dynamics, timing of seedling emergence and the fate of buried seeds in the natural habitat were investigated. PY was broken by mechanical scarification or wet heat/ice water cycles but not solely by dry heat or wet heat treatment. The soil seed bank exhibited seasonal changes in the number of seeds, which was highest in September and lowest in July. Seeds buried at different sand depths gradually lost dormancy; 20–42% of the seeds remained dormant after 20 months of burial. Dormancy break occurs gradually throughout the year. Our results indicate that O. racemosa exhibits hardcoatedness heterogeneity that spreads germination of a seed cohort between seasons and years in the semiarid environment, where the amount of precipitation during the growing season is highly variable.

The true depth of the Mediterranean plastic problem: Extreme microplastic pollution on marine turtle nesting beaches in Cyprus

We sampled 17 nesting sites for loggerhead (Caretta caretta) and green turtles (Chelonia mydas) in Cyprus. Microplastics (<5 mm) were found at all locations and depths, with particularly high abundance in superficial sand. The top 2 cm of sand presented grand mean ± SD particle counts of 45,497 ± 11,456 particles m−3 (range 637–131,939 particles m−3). The most polluted beaches were among the worst thus far recorded, presenting levels approaching those previously recorded in Guangdong, South China. Microplastics decreased with increasing sand depth but were present down to turtle nest depths of 60 cm (mean 5,325 ± 3,663 particles m−3. Composition varied among beaches but hard fragments (46.5 ± 3.5%) and pre-production nurdles (47.8 ± 4.5%) comprised most categorised pieces. Particle drifter analysis hindcast for 365 days indicated that most plastic likely originated from the eastern Mediterranean basin. Worsening microplastic abundance could result in anthropogenically altered life history parameters such as hatching success and sex ratios in marine turtles.

MORPHOLOGY OF FRUITS AND SEEDS AND GERMINATE AND INITIAL DEVELOPMENT ANALYSIS OF Hancornia speciosa

ABSTRACT The aim of this study was to analyze the stress effects caused by sowing depth and the amounts and in the substrate; characterize the fruits and seeds of Hancornia speciosa (Mangaba); to analyze the germination and the initial development, 150 days after planting. A total of 572 fruits, collected in three localities in the Porto Nacional - TO region, were analyzed for longitudinal and transverse length, fresh mass, number of seeds and seed mass. The results showed values higher than those found in other studies, indicating that the fruits presented larger size and mass, although they presented a higher number of seeds per fruit. Germination potential was analyzed in the laboratory, and the effects of seeding depth and percentage of sand on the substrate, germinability and development were studied in the plant nursery. In the laboratory and plant nursery, respectively, the percentage of germination was 74.4% and 51.5%; mean germination time of 11 and 17 days and synchronization of germination of 2.79 and 2.75. The Weibull cumulative model to express germination behavior of H. speciosa had a good fit of the model to describe the observed data and its parameters (G, , ) served to compare the effect of germination expression on time. Both germination and early development characters should be best when applied at 1 cm depth and add up to 15% sand to the substrate.

Wormlions prefer both fine and deep sand but only deep sand leads to better performance.

Wormlions are small fly larvae that dig pits in loose soil to trap their prey. Similar to other trap-building predators, like spiders and antlions, they depend on the habitat structure for successful trap construction and prey catch. We examined whether sites at which wormlions are present differ in sand depth and particle size from nearby sites, at which wormlions are absent. Next, in the laboratory we manipulated both sand depth and type (fine vs. coarse) to determine their joint effect on microhabitat preference, the size of the constructed pit, wormlion movement, and their latency to respond to prey. We expected better performance by wormlions in fine and deep sand, and the sand in wormlions’ natural sites to be finer and deeper. However, in only partial agreement with our expectations, wormlion sites featured finer sand but not deeper sand. In the laboratory, wormlions preferred both fine and deep sand, and moved more in shallow and coarse sand, which we interpret as an attempt to relocate away from unfavorable conditions. However, only deep sand led to larger pits being constructed and to a faster response to prey. The preference for fine sand could, therefore, be related to other benefits that sand provides. Finally, body mass was a dominant factor, interacting with the preference for both deep and fine sand: deep over shallow sand was more favored by large wormlions and fine over coarse sand by smaller ones. Our results suggest that several factors should be incorporated when studying microhabitat selection.

Integrating facies‐based Bayesian inversion and supervised machine learning for petro‐facies characterization in the Snadd Formation of the Goliat Field, south‐western Barents Sea

ABSTRACTSeismic petro‐facies characterization in low net‐to‐gross reservoirs with poor reservoir properties such as the Snadd Formation in the Goliat field requires a multidisciplinary approach. This is especially important when the elastic properties of the desired petro‐facies significantly overlap. Pore fluid corrected endmember sand and shale depth trends have been used to generate stochastic forward models for different lithology and fluid combinations in order to assess the degree of separation of different petro‐facies. Subsequently, a spectral decomposition and blending of selected frequency volumes reveal some seismic fluvial geomorphological features. We then jointly inverted for impedance and facies within a Bayesian framework using facies‐dependent rock physics depth trends as input. The results from the inversion are then integrated into a supervised machine learning neural network for effective porosity discrimination. Probability density functions derived from stochastic forward modelling of endmember depth trends show a decreasing seismic fluid discrimination with depth. Spectral decomposition and blending of selected frequencies reveal a dominant NNE trend compared to the regional SE–NW pro‐gradational trend, and a local E–W trend potentially related to fault activity at branches of the Troms‐Finnmark Fault Complex. The facies‐based inversion captures the main reservoir facies within the limits of the seismic bandwidth. Meanwhile the effective porosity predictions from the multilayer feed forward neural network are consistent with the inverted facies model, and can be used to qualitatively highlight the cleanest regions within the inverted facies model. A combination of facies‐based inversion and neural network improves the seismic reservoir delineation of the Snadd Formation in the Goliat Field.

Metacommunity analysis of meiobenthos of deep-sea sediments from the Gulf of Mexico

Metacommunity theory is a conceptual framework addressing the interdependence of local interactions and regional processes, especially when it is difficult to relate community structure and the environment at different spatial scales. To test the applicability of this theory to meiobenthos, 27 deep-sea sediment samples from the Gulf of Mexico were analyzed for meiobenthic and nematode community distribution and structure along with a set of environmental variables. Spatial and temporal heterogeneity in environmental conditions were found among sampling stations, and some variables, such as depth, inorganic carbon, carbon/nitrogen ratio, bottom-water oxygen, and percentage of sand, proved influential on total community abundance. Nematodes were the dominant meiofaunal group and its abundance highly variable among sites and sampling periods. Nematofauna was dominated by bacterivores, which also possessed the highest maturity index. Environmental characteristics showed a significant relation with community structure, not so the dispersal of nematode genera. In light of our findings, we posit that the deep-sea meiobenthos of the Gulf of Mexico may represent a metacommunity following the “species-sorting model.” This inference is based on the different taxonomic structures among sampling stations correlating with environmental differences, in the presence of local niche diversification and limited dispersal.

Residuals Efficacy of Thiamethoxam and Thiaclopride Soil Applications against Whitefly, Bemisia tabaci (Homoptera; Aleyrodidae) and Their Impact on Soil Microarthropods

Field studies werecarried out to investigate the efficacy of thiamethoxam (TMX) and thiaclopride(THI) via three different types of soil against whitefly, Bemisia tabaci,on tomato seedlings during two successive seasons. Physical and chemicalcriteria were determined in each of soil type. Results revealed that, the soiltypes were loamy sand (Al-Maamoura), silt loam (Bangar Al-Sokkar) and clay(Abou-Homous). During 2016 and 2017, clay soil had the highest contents inorganic matter (3.43 and 3.48% respectively) and organic carbon (1.99 and 2.03%respectively). The highest mean reduction percentages of whiteflytreatedwith the TMX in loamy sand soil were 79.35 and 80.12% and in silt loam were78.39 and 81.60% during 2016 and 2017comparing to clay soil. Likewise, THI hadthe highest mean reduction percentages during 2016 and 2017 in loamy sand soil (78.06and 79.88% respectively) and silt loam (77.12 and 78.56% respectively) comparedto clay soil. Residuals efficacy of TMX and THI extended to 15 days in loamysand and silt loam soils compared to 9 days in clay soil during the two seasonsand the season of 2016 respectively. During the season of 2017, THI had moreextension for a week in the three tested soils. Initial effects againstwhitefly had a rapid onset on the 3rd day post-treatments of TMX inloamy sand and THI in silt loam and clay soils during the two seasons. Initialeffects delayed on the 9th day post treatment of TMX in silt loamsoil during season of 2017and in clay soil during the two seasons.Retardations, extended to the 9th day of THI treatment in loamy sandsoil during the season of 2017. The efficiencies of TMX and THI via soils ofloamy sand and silt loam against whitefly were significantly more than claysoil. Full recovery levels ofmicro-arthropods revealed at the end of the 7th week in all soil’s depths of loamy sand and siltloam treated with TMX and in loamy sand soil treatedwith THI during the two seasons. Treated areas of high OM -clay soil failed to reach the recovery levels.

Lateral behaviour of a pile group due to side-by-side twin tunnelling in dry sand: 3D centrifuge tests and numerical modelling

This paper presents lateral responses of an existing 2 × 2 pile group to advancement of side-by-side twin tunnels (with 1% volume loss) at various depths in dry sand using 3D centrifuge and numerical modelling. The tunnels were located near mid-depth of the pile shaft (test SS), next to (test TT) and below the toe (test BB) of the pile group. The largest and the smallest lateral movement of the pile cap was induced after first tunnelling in test TT and test SS, respectively. The shearing force was induced in piles as a reaction of pile deflection in tests TT and BB.

PENYELIDIKAN KELAYAKAN KIMIA DAN PENYEBARAN CADANGAN PASIR BESI DAERAH TIKU KABUPATEN AGAM UNTUK BAHAN BAKU SEMEN PADA PT. SEMEN PADANG

The purpose of this research is to know the mineral content of iron sand and its spreading both vertically and horizontally with the purpose of providing information and data for local government of Agam district for the development and arrangement of environment along the coast. In order to obtain information about the depth of iron sand can be used geoelectric method because one of the physical properties of metal elements including iron is to have low resistivity. In this study used resistivity mapping method that aims to determine the variation of the arrangement of soil layers vertically and horizontally. The configuration used in this method is Schlumberger configuration. To know the chemical content of iron sand is done by taking samples of iron sand systematically and represented at some point. The sample was analyzed chemical composition by XRF method (X-Ray Fluorescence), then correlated with some surface data, so that the depiction of the quality of iron sand of Tiku Regency. From the interpretation of soil resistivity value on 2 paths it can be concluded that iron sand in Tiku Beach area is in depth 0 - 20 m. Chemical content of iron sand from XRF method analysis shows Fe2O3 percentage of 10 - 35%, with TiO2 content of 1 - 3%. The quality of iron sand can be used as raw material for cement maker.

Analysis of Time-Depth Data in Sand Dunes from the Empty Quarter Desert of Southeastern Saudi Arabia

Theoretical and field studies show that P-wave velocity increases continuously with depth in unconsolidated sands. Many analytical and empirical models have been proposed to account for this phenomenon in near-surface layers. This study presents five new uphole data sets acquired in sand dunes located in the Empty Quarter (Rub’ Al-Khali) Desert in southeastern Saudi Arabia. Furthermore, the study compares the following velocity-depth functions: constant-velocity, Al-Shuhail, and Liner by fitting them to these data sets in addition to the sand curve data set. The constant-velocity function estimates an average P-wave velocity equal to 641 m/s in the dunes with an average sum of squared errors \(\hbox {(SSE)} = 0.00101\). Liner’s velocity function estimates an average surface P-wave velocity = 450 m/s and an average porosity (\(\phi ) = 38.33\%\) in the dunes with an average \(\hbox {SSE} = 0.000133\). Al-Shuhail’s velocity function estimates an average surface P-wave velocity \( = 25.78\,\hbox {m/s}\) and an average velocity-depth gradient \( = 662\,\hbox { m}^{-1/3}\) in the dunes with an average \(\hbox {SSE} = 0.0000877\).

Antagonistic effects of drought and sand burial enable the survival of the biocrust moss &amp;lt;i&amp;gt;Bryum argenteum&amp;lt;/i&amp;gt; in an arid sandy desert

Abstract. Biocrust moss is an essential soil surface bio-cover. It can represent the latest succession stage among the diverse range of surface-dwelling cryptogams (e.g., cyanobacteria, green algae, and lichen, which are also referred to as biocrusts), and it can make a major contribution to soil stability and fertility in many arid sandy desert ecosystems. The soil surface represents a very large ecological niche that is poikilohydric in nature. Biocrust moss is therefore highly susceptible to drought and sand burial, which are two ubiquitous stressors in arid sandy deserts. However, little information is available regarding the mechanism by which biocrust moss can survive and flourish in these habitats when stressed simultaneously by the two stressors. The combined effects of drought and sand burial were evaluated in a field experiment using the predominant biocrust moss, Bryum argenteum Hedw., in the Tengger Desert, China. Drought was simulated by applying distilled water in three artificial rainfall regimes at 8-day intervals in spring and autumn: 4 and 6 mm (average rainfall, control), 2 and 3 mm (double drought), and 1 and 1.5 mm (4-fold drought), respectively. The effect of sand burial was determined by applying six treatments, i.e., sand depths of 0 (control), 0.5, 1, 2, 4, and 10 mm. The four parameters of chlorophyll a content, PSII photochemical efficiency, regeneration potential, and shoot upgrowth were evaluated in the moss. It was found that the combined effects of drought and sand burial did not exacerbate the single negative effects of the four parameters tested. Drought significantly ameliorated the negative effects of deep-sand burial on the retention of chlorophyll a content, PSII photochemical efficiency, and the regeneration potential of B. argenteum. Sand burial diminished and even reversed the negative effects of drought on the maintenance of chlorophyll a content, PSII photochemical efficiency, and regeneration potential. Although drought and sand burial imposed an additive negative effect on shoot upgrowth, which suggested a trade-off between growth ability and stress tolerance, their mutually antagonistic effect on the physiological vigor of B. argenteum provided an opportunity for the biocrust moss to overcome the two co-occurring stressors. In addition to providing a strong stress tolerance, drought and sand burial may provide an important mechanism for the biodiversity maintenance of biocrust mosses in arid sandy ecosystems.