Altitude Decreases Research Articles

Determination of the eddy diffusion in the Venusian clouds from VeRa sulfuric acid observations

Context. The vertical eddy diffusion coefficient (Kzz) characterizing the efficiency of vertical atmospheric mixing is essential for 1D planetary atmospheric modeling, but poorly constrained in the Venusian clouds, where our ability to observe tracer gases is limited. The Venusian clouds are mainly composed of H2SO4, which has significant mass cycles in this region. A critical process herein is that the H2SO4 vapor abundance in the middle and lower clouds of Venus is regulated by both condensation and eddy diffusion processes. Aims. This study is devoted to proposing a novel approach to estimating the Venusian cloud Kzz, examining the variability of the cloud Kzz in both equatorial and polar regions, and evaluating the derived Kzz through the implementation of a 1D photochemical model. Methods. The H2SO4 vapor data used in this study were obtained from observations conducted by Venus Express. A novel approach that relies on the premise that both eddy diffusion and condensation regulate the abundance of H2SO4 vapor was then applied to estimate the Venusian cloud Kzz. The global mean Kzz and its latitudinal variation were discussed. A 1D photochemistry-diffusion model was applied to evaluate the estimations. Results. Our calculations indicate that the global mean Kzz reaches 5 × 108 cm2 s−1 in the lower clouds, which is an order of magnitude larger than several observation-based estimations and model results. It rapidly decreases as the altitude increases above 54 km. Equatorial Kzz is three times as large as polar Kzz at 48 km, while polar Kzz reaches its peak below 46.5 km, where equatorial Kzz rapidly decreases as the altitude decreases. Conclusions. We provide an estimate of the Venusian cloud Kzz based on H2SO4 vapor observations. Significant latitudinal variations exist in the Venusian cloud Kzz.

The radiometric environment for Mars limb observations by the Mars Sample Return Earth Return Orbiter

After launching from the martian surface via the Mars Ascent Vehicle (MAV), the MAV and the Orbiting Sample (OS) capsule containing the samples collected on Mars by the Perseverance rover are to be identified by the Narrow Angle Camera (NAC) on the Earth Return Orbiter (ERO) spacecraft in order to determine the exact orbit of the capsule before rendezvous. To ensure detection of the OS, noise and straylight contributions to the NAC must be well characterized. Here, we assess the radiometric environment at Mars likely to be encountered by the NAC—from the surface through the middle atmosphere—using the High Resolution Stereo Camera (HRSC) onboard Mars Express (MEx) and the Mars Climate Sounder (MCS) onboard the Mars Reconnaissance Orbiter (MRO). The results show that the radiance values in general tend to increase as phase angle increases, as the season progresses from Ls = 60° to Ls = 230°, and as altitude decreases. We compare HRSC and MCS profiles where observing conditions were similar and find good agreement. At specific latitudes, high-altitude aerosols are present in 1–5% of observations and significantly increase the worst-case radiance contribution above 50 km. We construct envelope profiles from the maximum radiances at 5 km intervals from 0 to 90 km that provide important input for straylight calculations of the NAC and for the validation of models that may be used as input for straylight calculations.

Contrasting molecular characteristics and formation mechanisms of biogenic and anthropogenic secondary organic aerosols at the summit and foot of Mt. Huang, East China

Secondary organic aerosol (SOA) exerts a considerable influence on atmospheric chemistry. However, little information about the vertical distribution of SOA in the alpine setting is available, which limited the simulation of SOA using chemical transport models. Here, a total of 15 biogenic and anthropogenic SOA tracers were measured in PM2.5 aerosols at both the summit (1840 m a.s.l.) and foot (480 m a.s.l.) of Mt. Huang during the winter of 2020 to explore their vertical distribution and formation mechanism. Most of the determined chemical species (e.g., BSOA and ASOA tracers, carbonaceous components, major inorganic ions) and gaseous pollutants at the foot of Mt. Huang were 1.7–3.2 times higher concentrations than those at the summit, suggesting the relatively more significant effect of anthropogenic emissions at the ground level. The ISORROPIA-II model showed that aerosol acidity increases as altitude decreases. Air mass trajectories, potential source contribution function (PSCF), and correlation analysis of BSOA tracers with temperature revealed that SOA at the foot of Mt. Huang was mostly derived from the local oxidation of volatile organic compounds (VOCs), while SOA at the summit was mainly influenced by long-distance transport. The robust correlations of BSOA tracers with anthropogenic pollutants (e.g., NH3, NO2, and SO2) (r = 0.54–0.91, p < 0.05) indicated that anthropogenic emissions could promote BSOA productions in the mountainous background atmosphere. Moreover, most of SOA tracers (r = 0.63–0.96, p < 0.01) and carbonaceous species (r = 0.58–0.81, p < 0.01) were correlated well with levoglucosan in all samples, suggesting that biomass burning played an important role in the mountain troposphere. This work demonstrated that daytime SOA at the summit of Mt. Huang was significantly influenced by the valley breeze in winter. Our results provide new insights into the vertical distributions and provenance of SOA in the free troposphere over East China.

Milk Composition of Creole Goats Raised at Different Altitudes in an Extensive Production System in Northeast Mexico.

Goat milk composition is affected by feeding, and in semiarid rangeland, information on Creole goat milk physicochemical composition is lacking. For the fulfillment of this objective, three agroecological regions (AR) considering altitude (lowland 87, highland 779, and mountain 1309 m above sea level) with different botanical compositions were chosen. Every AR analyzed accounted for 30 goat herds, with a total of 90 herds. The results demonstrated that altitude had an influence mainly on density and protein. Milk density increases as altitude increases; conversely, milk protein increases as altitude decreases. On the other hand, in the mountain and lowland ARs, the salts and solids not fat (SNF) percentages were higher compared to that of the highland AR (p < 0.05). The freezing point (FP) was higher at highland altitudes compared to that of mountain and lowland ARs (p < 0.01). In the milk fatty acids (FA) profile, only the C14:1 value was affected by altitude, whereas goat milk at lowland and mountain altitudes had higher values compared to that at highland altitudes (p < 0.05). Additionally, late lactation stage fat, FP, and pH values were higher compared to early lactation values. The opposite effect was observed for salts and SNF. In the FA profile, late lactation values were higher for C10:0 and C8:0 compared to early lactation values. The opposite trend was observed for C18:2n6t. The thrombogenic index was significantly higher at lowland altitudes compared to highland altitudes, and similar to the mountain AR. These goat milk characteristics could be explained as a consequence of animal nutrition, as well as the goat's meat-type phenotype.

On the origin of the ground effect

The ground effect is well known to pilots and aerodynamicists alike. However, the current explanations found in undergraduate (and pilot-focused) textbooks can be inconsistent, often attributing the phenomena to the interaction between tip vortices at the ground. Others invoke the method of images to show that, when the flow is forced to have a straight streamline on the ground, ground pressure must increase. These must prescriptively choose an airfoil circulation. Meanwhile, a simple panel code can be used to show both that the lift on an airfoil in ground effect is significantly two-dimensional, and that the circulation about an airfoil near the ground is not constant. In particular, circulation will be found to grow as altitude decreases, magnifying the ground effect. A simple graphical panel method solver is provided, such that this exercise is accessible to students without the longer task of writing a panel code for themselves. This exercise can provide students with greater insight into the Kutta condition, the method of images, and panel methods themselves. The resulting streamline pattern can also be used to explain the phenomenon to more general audiences, by observing the relationship between lift and streamline curvature.

Stratospheric intrusion may aggravate widespread ozone pollution through both vertical and horizontal advections in eastern China during summer

Stratospheric intrusion (SI) is an important source of tropospheric ozone (O3). Here, we used the online coupled Weather Research and Forecasting-Chemistry (WRF-Chem) model to simulate a typical SI event that occurred over eastern China on 15–19 July 2016 and investigate the impacts of SI on near-surface O3 pollution. The results show that the large-scale circulation of SI was characterized by a deep trough over central China and South Asia high and Western Pacific Subtropical high located to the east and west of the deep trough, respectively. With the evolution of the deep trough, the strong downdrafts behind the trough lead to O3-rich air injected into the lower troposphere across eastern China. By using a tracer tagging method in WRF-Chem, we quantified the SI contributed up to 6.5 ppb to the surface O3 concentration. According to the integrated process rate analyses, which were employed to quantify the contribution of different physical/chemical processes to O3, the advection process dominated variations in troposphere O3 with positive contribution ranging from 0.1 to 13.8 ppb h−1. As altitude decreases, the contribution of advection diminishes as the intensity of the SI gradually weakens. Although the vertical advection contributed limited O3 that directly reached the ground, we revealed that the SI has significant impact on near-surface O3 over a large territory of eastern China through regional transport by horizontal advection process. Below 691 m, the positive contribution of horizontal advection to O3 ranges from 1.6 to 13.4 ppb h−1. This study highlights the natural effect of SI on summertime O3 pollution in eastern China and will help the development of a future O3 pollution alert system.

Quantification of the role of gravity wave induced TIDs in modulating ESF day to day variability during geomagnetically disturbed periods

The control of magnetic disturbance induced seed perturbations on the daily variation in night-time ionization irregularity occurrence is studied using ionosonde data and TIMED/GUVI neutral density data at the magnetic equatorial region, Trivandrum. The study reveals that there is a requisite threshold seed amplitude for ESF to occur at a particular altitude and this requisite seed increases as the altitude decreases. This dependence of requisite seed perturbation on altitude for multiple years, which incorporates the electrodynamical effects also, is used as the basis for developing an empirical model to hind-cast ESF. Using the model, the threshold seed perturbation for any day of vernal equinox (ve) season of any year can be delineated if the solar flux index (F10.7) is known. The empirical model is also validated using the data for high and low solar activity periods. The model is able to hind-cast ESF with 92% success for low solar activity while the success rate for high solar activity is 50%. Further, the dependence of the threshold curves on neutral density is brought out, thereby confirming the role of ion-neutral coupling processes in modulating the same for magnetically disturbed periods. The geomagnetically disturbed period requisite seed amplitudes are higher than those for quiet periods at a given altitude. This study underlines the importance of disturbance induced seed perturbations and neutral density in controlling ESF occurrence.

Isotopic differences in soil–plant–atmosphere continuum composition and control factors of different vegetation zones on the northern slope of the Qilian Mountains

Abstract. Understanding the differences and control factors of stable water isotopes in the soil–plant–atmosphere continuum (SPAC) of different vegetation zones is of great significance in revealing hydrological processes and regional water cycle mechanisms. From April 2018 to October 2019, we collected 1281 samples to investigated the stable water isotopes' changes in the SPAC of three different vegetation zones (alpine meadows, forests, and arid foothills) in the Shiyang River basin. The results show the following: (1) precipitation plays a major control role in the SPAC. From alpine meadows to arid foothills, the temperature effect of precipitation isotopes increases as altitude decreases. (2) From the alpine meadow to the arid foothills, soil water isotopes are gradually enriched. (3) Alpine meadow plants are mainly supplied by precipitation in the rainy season, and forest plants mainly utilize soil water in the dry season and precipitation in the rainy season. The soil water in the arid foothills is primarily recharged by groundwater, and the evaporation of plant isotopes is strong. (4) Temperature and altitude are potential factors that control the isotopic composition of the SPAC. This research will help in understanding of the SPAC system's water cycle at different altitudes and climates in high mountains.

High Altitude Decreases Bone Mineral Density and the Mediation Effect of Gut Microbiota

High Altitude Decreases Bone Mineral Density and the Mediation Effect of Gut Microbiota

Assessing paraglacial processes at Nexpayantla Gorge (Popocatépetl volcano, Central Mexico) using OSL and14C

AbstractWe evaluate the paraglacial activity in Nexpayantla, a subtropical mountainous gorge in Popocatépetl volcano (Central Mexico), fully deglaciated in the 20th century. Glacial advances are evidenced by the presence of moraines. Fluvio‐glacial terraces and an alluvial megafan resulted from the gorge deglaciation. Current reworking of the glacigenic material is done by landslides and debris flows produced on the moraines and terraces. To study the different phases of mobilization of glacigenic sediment, we used an approach based on the study of the optically stimulated luminescence (OSL) signals obtained from a portable OSL (POSL) reader in samples extracted from both glacigenic and paraglacial deposits. The luminescence (POSL) results obtained at moraines increase as altitude decreases, which is expected for deglaciated valleys where the oldest moraines are located at lower elevations. We evaluate the grade of luminescence signal reset of the glacigenic sediments during the proglacial stage, and the subsequent deglaciation phases. Our results indicate that there is a marked transition between glacial and fluvially dominated processes at Nexpayantla Gorge. We find that the grade of luminescence signal resetting in the paraglacial deposits is a good indicator to trace paraglacial stages and the beginning of exhaustion of the paraglacial activity in mountain areas. OSL ages confirm that the oldest fluvio‐glacial terraces found at the middle sector of Nexpayantla Gorge are ~2 ka, which is also supported by an AMS14C age. OSL dating was found challenging, since quartz grains have low sensitivity because of their volcanic origin; POSL signals, however, are in good agreement with the location and distribution of geomorphic markers. We propose that luminescence data obtained from the POSL unit can be useful to provide information about sediment mobilization in paraglacial environments during different climatic pulses – even for the case where mineral grains have low sensitivity, such as in volcanic sediments. © 2020 John Wiley &amp; Sons, Ltd.

Life form dynamics of the tree layer in evergreen and deciduous broad-leaved mixed forest during 1996–2017 in Tianmu Mountains, eastern China

In the forest areas of eastern China, there is a change from forest dominated by deciduous broad-leaved trees to forest dominated by evergreen broad-leaved trees as the latitude or altitude decreases. Different life forms have different survival strategies to deal with climate change, and studying the life form dynamics of the tree layers in the mixed forest in eastern China, with increasing temperature, can help us understand how the forest responds. This study was performed in a 1 ha plot in evergreen and deciduous broad-leaved mixed forest in Tianmu Mountain National Nature Reserve. Based on the data from two surveys (1996 and 2017), the changes in life form composition and biodiversity over the past 21 years were analyzed. We obtained the following results: (1) The proportion of evergreen trees increased from 55.0% in 1996 to 67.5% in 2017, and the dominance of evergreen species was enhanced. (2) The diversity of both life forms increased, and the tree species were more abundant. (3) The average annual recruitment rate of the evergreen species was 2.1% greater than their mortality rate, and the average annual recruitment rate of the deciduous species was 0.5% less than their mortality rate. (4) The competition among the trees in the small-diameter class (10 cm ≤ DBH &lt; 20 cm) was fierce for many tree species. The proportion of the evergreen species in the small-diameter class was high. The life forms making up the mixed climax forest community has changed over the past 21 years, with the proportion and dominance of evergreen trees increasing significantly.

Power-Optimal Guidance for Planar Space Solar Power Satellites

This paper presents power-optimal guidance for a planar space solar power satellite (SSPS). Power-optimal guidance is the attitude trajectory that maximizes the solar power transmitted by the SSPS. Planarity is important because it couples the orientations of the SSPS’s photovoltaic and antenna surfaces. Hence, the transmitted power depends on the relative geometry between the SSPS, the sun, and the receiving station. The orientation that maximizes power transfer changes as this relative geometry changes. Both single- and dual-sided SSPS architectures are considered. A single-sided SSPS has one photovoltaic surface and one antenna surface. A dual-sided SSPS is a single-sided SSPS with at least one additional photovoltaic or antenna surface. Geometric arguments show that a dual-sided SSPS has superior performance to a single-sided SSPS. Power-optimal guidance is then presented for the special cases of SSPSs in geostationary Earth orbit, medium Earth orbit, and low Earth orbit transmitting to an equatorial receiving station at the time of Earth’s vernal equinox. These examples emphasize important solution properties, including the need for large slew maneuvers, and they show that, even though system efficiency decreases as orbit altitude decreases, reduced path losses actually increase the amount of received energy per unit aperture area. This has significant system implications for future space solar power missions.

White stork nest altitude decreases as global temperatures increase

Climate change causes altitudinal shifts of animal distributions and this effect can potentially be accentuated or altered due to human agricultural activities. Because of the availability of uniquely long-term monitoring data, we chose the white stork (Ciconia ciconia) as a model species. We analyzed large data sets (record cards from 1191 nests) covering the long-term period from 1875 to 2005 in the Czech Republic, central Europe. We analyzed nest altitude during years of founding of the nest, temperature, land use variables and types of nests (natural vs. human provided nest pads). Consistent with findings from previous studies we predicted a temporal increase in the altitude of white stork nests. Surprisingly, we found that the altitude of nests was decreasing, despite an increase in local mean spring temperatures. The altitude of nests was higher when the proportion of arable land, water areas and developed land was lower and when the proportion of grass and forest cover was greater. The decrease in altitude was significant in natural nests (built by storks) but non-significant in nests on nest platforms (built by humans). Thus, human agricultural activities might potentially override the opposing effects of global climate change on animal altitudinal distribution shifts.

The characteristics of ozone concentration over the maritime equatorial stratospheric region derived from the quasi-biennial oscillation

The characteristics of ozone concentration [O3] over the Maritime Equatorial Stratospheric region until now are not yet fully understood well due to the limitation of data observations. However, there are many techniques to derive ozone concentration data; from satellite, in-situ observation, modeling, etc. We have investigated, then found a good agreement between the characteristics of ozone concentration and Quasi-Biennial Oscillation (QBO). This study mainly concerned with the analysis of the stratospheric zonal wind from Singapore’s QBO monthly data at 100-10 hPa layers. Total ozone, ozone mass mixing ratio, and stratospheric temperature were considered in the analysis. Predominant peak oscillation in each layer was investigated by using the spectral technique. The result shows that a strong signal of zonal wind oscillation pattern was evident at 30 hPa layer. As the altitude decreases, zonal wind oscillation decays. Box-Jenkins final model contained 28 months of a seasonal component (5,0,4)(0,1,0)28 and a percentage error of 46.6%, whereas multiple linear regression obtained a quite good correlation score, which was about 0.55.

Light propagation characteristics of turbulent plasma sheath surrounding the hypersonic aerocraft**Project supported by the National Natural Science Foundation of China (Grant No.61431010).

The characteristics of light propagation through turbulent plasma sheath surrounding the hypersonic aircraft have been studied. The turbulent flow fields around a hypersonic aircraft are given by using the Navier–Stokes (NS) equations and k–ε turbulence model. Based on the distribution of flow field, refractive index and density of the plasma sheath for a blunt cone are discussed with different flight velocities and altitudes. The refractive index is mainly influenced by the electrons in the turbulent plasma sheath. The influence of different velocities and altitudes on the features of light propagation in the turbulent plasma sheath is analyzed. The results show that as the flight speed increases or the flight altitude decreases, the refractive index fluctuation becomes larger. It is also found that the refractive index fluctuation varies with the incident wavelength. This study shows how the characteristics of an optical beam propagating through plasma sheath are affected by the incident wavelength, flight velocities, and altitudes.

Altitude-dependent distribution of 137Cs in the environment: a case study of Aragats massif, Armenia

This paper considers the distribution of technogenic 137Cs and naturally occurring radionuclides: 238U, 232Th and 40К concentrations in soils and 137Cs in atmospheric dry depositions by altitudinal belts of the Aragats mountain massif, Republic of Armenia. Undisturbed soil samples were collected at altitudes from 1000 to 3200 m. For the determination of geochemical variability, two soil sampling campaigns were undertaken. Atmospheric dry depositions were sampled from five stations at 1100–3200 m collected onto organic fiber filters between June and December 2016. 137Cs activity was measured using a high-purity Germanium detector coupled to a multichannel analyzer (Canberra). Results indicated that specific activity of 137Cs in soils at 1000 m is 495–528 Bq m−2, and at 3200 m is 10,500–11,470 Bq m−2. No correlation observed for 137Cs versus naturally occurring radionuclides, which varies in distribution by altitude. Specific activities of 137Cs in dry atmospheric depositions varies from 1.06 at 846 m to 2.37 Bq m−2 per quarter at 3200 m and increases as the altitude increases. Activities of 137Cs in soil and dry atmospheric deposition correlated significantly, and 137Cs activity in soils and atmospheric dry depositions decrease as the absolute altitude decreases. The 50-year effective dose from exposure to 137Cs fallout varies with altitude from 0.007 to 1.42 mSv.

Vertical coupling between the mesopause region and sporadic-E layer during equatorial counter electrojet events – A case study

This paper presents a case study exploring the variability of daytime ionospheric sporadic E (Es) during Counter Equatorial Electrojet (CEJ) events over Trivandrum (8.5°N, 77°E, 0.5°N dip lat.), a dip equatorial station in India. It makes use of collocated measurements of (a) daytime mesopause temperature estimated using a Multiwavelength Dayglow Photometer, (b) base height of sporadic E-layer i.e. Esq obtained from a Digital Ionosonde, (c) Equatorial Electrojet (EEJ) induced magnetic field at the surface measured using a Proton Precession Magnetometer and (d) neutral meridional and zonal winds measured using meteor wind radar. The study addresses why, only on certain CEJ days, the Es layer turns into a blanketing Es layer, also referred to as Esb layer, appearing for a brief period and almost simultaneously as the CEJ induced magnetic field on the surface is either zero or very small, and not on all the CEJ days despite the reversal of the zonal winds in the dynamo region (∼98 km). Further, a simulation using the simultaneously measured zonal wind and temperature shows that during CEJ, especially when the zonal wind reverses and the mesopause temperature lowers, the conditions are in fact less favourable for the ionization to converge resulting in Esb. On the other hand, on such occasions, the meridional wind exhibits a tendency to turn equatorward with time with the changeover gradually happening as the altitude decreases. These observations have been discussed to allude to the possible role of the overall wind system and its spatio-temporal changes in the ionospheric altitudes which could influence the gradual transition of Esq to Esb over the dip equator.

Centrifugal Blower of Stratospheric Airship

In order to keep airship shape and realize desired performance during the course of landing safely from 20-km altitude, a specific blower is needed to be designed, and its characteristics should be analyzed. The CFturbo software is used to design the stratospheric blower. The performance of the designed stratospheric blower is calculated by computational fluid dynamics software PumpLinx simulation. Then, the performance of the blower at different altitudes is analyzed by simulation. It is shown that the designed stratospheric blower can basically meet the requirements of the semirigid airship of 160 m in length. The blower can make the airship land safely, and its efficiency can reach about 77% in the stratosphere. As the altitude decreases, the efficiency and volume flow (at different heights) of the blower gradually decrease. In addition, the sensitivity of different geometric parameters to the efficiency is analyzed, which can provide a reference for the optimization design of the stratospheric blower.

Seasonal variability of stratospheric methane: implications for constraining tropospheric methane budgets using total column observations

Abstract. Global and regional methane budgets are markedly uncertain. Conventionally, estimates of methane sources are derived by bridging emissions inventories with atmospheric observations employing chemical transport models. The accuracy of this approach requires correctly simulating advection and chemical loss such that modeled methane concentrations scale with surface fluxes. When total column measurements are assimilated into this framework, modeled stratospheric methane introduces additional potential for error. To evaluate the impact of such errors, we compare Total Carbon Column Observing Network (TCCON) and GEOS-Chem total and tropospheric column-averaged dry-air mole fractions of methane. We find that the model's stratospheric contribution to the total column is insensitive to perturbations to the seasonality or distribution of tropospheric emissions or loss. In the Northern Hemisphere, we identify disagreement between the measured and modeled stratospheric contribution, which increases as the tropopause altitude decreases, and a temporal phase lag in the model's tropospheric seasonality driven by transport errors. Within the context of GEOS-Chem, we find that the errors in tropospheric advection partially compensate for the stratospheric methane errors, masking inconsistencies between the modeled and measured tropospheric methane. These seasonally varying errors alias into source attributions resulting from model inversions. In particular, we suggest that the tropospheric phase lag error leads to large misdiagnoses of wetland emissions in the high latitudes of the Northern Hemisphere.

Ecosystem Services Evaluation and Its Spatial Characteristics in Central Asia’s Arid Regions: A Case Study in Altay Prefecture, China

Ecosystem services are important foundations to realize the sustainable development of economy and society. The question of how to quantitatively evaluate ecosystem services in a scientific way is a hot topic among international researchers. Studying the spatial characteristics of ecosystem services in arid regions can provide the theoretical and practical basis for coordinating a sustainable man-land relationship. Altay Prefecture of China, a typical arid region in Central Asia, was taken as the study area. It is on the Silk Road economic belt, which is a key region in the program of developing Western China. Three ecosystem services: water yield, soil conservation, and net primary productivity were quantitatively evaluated. The results show that (1) the spatial distribution pattern has a distinct characteristic of zonality; (2) mountain zone and mountain-oasis ecotone are the hotspots of ecosystem services; and (3) the correlation between water yield and net primary productivity shows a gradual increasing trend as altitude decreases. Objective analysis from the aspect of mechanism is given by discussing the causes of this particular pattern. It is found that altitude and slope have great influence on spatial distributions of ecosystem services, zones with the most amount of services are distributed in 1.5–2 km-altitude and 15–25°-slope. Different human activities in different regions and spatial distance decay of ecosystem services also contribute to the formation of spatial pattern. Thus, overgrazing, logging and mining are prohibited in mountain zones and mountain-oasis ecotones. Scholars are encouraged to focus on desert-ecosystem services in the future.