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Abstract The Aral Sea, located in Central Asia, has undergone significant reduction in surface area owing to the combined impacts of climate change and human activities. This reduction has led to a regional ecological crisis and profound repercussions on ecosystem services. Investigating the spatiotemporal variations and synergistic trade-offs of ESs in the Aral Sea basin is crucial for fostering the integrated development of the region’s socioeconomic ecology. This study utilizes the Future Land-Use Simulation and InVEST models to analyze future land-use scenarios, integrating CMIP6 projections to assess the quality of four key ecosystem services: water production, soil conservation, carbon storage, and habitat quality over two timeframes: the historical period (1995–2020) and the projected future (2021–2100). Employing Spearman correlation, the study explores the trade-offs and synergies among these ecosystem services. Findings reveal that the primary forms of land-use change in the Aral Sea basin are the reduction in water area (− 49.59%) and the rapid expansion of urban areas (+ 504.65%). Temporally, habitat quality exhibits a declining trend, while carbon storage shows an increasing trend, and water production and soil retention fluctuate initially decreasing and then increasing. Spatially, water production and carbon storage demonstrate an increasing trend from the northwest to the southeast. Habitat quality exhibits a higher spatial pattern in the southeast and south, contrasting with lower spatial patterns in the north and west. Low-level soil conservation is predominantly distributed in the northwest, while medium to low-level soil conservation is prevalent in the east of the basin. The trade-off and synergy analysis indicates that between 1995 and 2020, a trade-off relationship existed between carbon storage and habitat quality and water production, whereas synergies were observed between soil conservation and carbon storage, water production and habitat quality, and soil conservation. The correlation between water production and soil conservation emerges as the strongest, whereas the correlation between carbon storage and habitat quality appears to be the weakest. The dynamic spatiotemporal changes, trade-offs, and collaborative relationships of ESs constitute major aspects of ecosystem service research, holding substantial implications for the effective management of the regional ecological environment.

Global challenges such as climate change, biodiversity loss, and health crises necessitate a shift towards sustainable diets. Incorporating sustainability into food-based dietary guidelines (FBDGs) is essential for this shift, and cultural considerations also play a vital role, as food culture significantly influences dietary habits. Considering that Asia and Europe exhibit distinct food cultures, tailored approaches are necessary. Additionally, countries face diverse nutritional challenges, ranging from malnutrition to diet-related diseases, and regional variation in environmental impact necessitates context-specific strategies. Achieving sustainable nutrition depends on understanding cultural influences and regional dynamics. This paper compares China’s and Germany’s dietary guidelines and dietary patterns and their impact on sustainability. It shows that Chinese and German FBDGs only slightly differ, despite the different eating cultures and habits of each country. Alone the recommended amounts for eggs and fish are considerably higher in China than in Germany. However, in both China and Germany, actual dietary patterns deviate from the dietary guidelines. In China, concomitant with economic growth and urbanization, a dietary shift towards increased consumption of animal products and decreased consumption of vegetables and cereals has been observed in the last decades, which has led to a decline in nutritional deficiencies but an increase in obesity and overweight. Obesity and overweight are also on the rise in Germany. A dietary shift could therefore also be beneficial for public health. While following the respective national guidelines would benefit the environment, alternative diets such as a plant-based diet offer even lower environmental footprint. Revising guidelines to prioritize sustainability in addition to health aspects while considering regional contexts and cultural preferences is recommended to foster sustainable eating habits globally. This approach is pivotal for promoting dietary shift towards sustainability on a global scale.

Study region: The Yangtze River basin (YRB) Study focus: This study presented a methodology for identifying short-term drought events, with a particular emphasis on rapid onset. The standardized antecedent precipitation evapotranspiration index (SAPEI) was adopted to detect drought at the grid level within a time series dataset, and a clustering algorithm was employed to identify drought events with three-dimensional structures, followed by a comprehensive analysis of their spatiotemporal characteristics and the factors contributing to spatial heterogeneity. New hydrological insights for the regions: The proposed method effectively captures the rapid intensification phase and the drought development processes. Short-term drought with rapid onset was predominantly observed in the northwestern region and the middle to lower reaches of the YRB from 1960 to 2014, exhibiting mild and moderate drought conditions. This spatial variability was related to the interactions among temperature, potential evapotranspiration, precipitation and wind. Furthermore, a total of 246 three-dimensional drought events were identified in the YRB. Among these events, centroid no-transfer events were prevalent, and the primary migration direction for centroid transfer events was from southeast to northwest. Additionally, short-term drought events displayed a characteristic evolution pattern, with the affected area remaining relatively stable while drought intensity exhibited a significant decrease which indicated the drought rapidly developed into more severe drought condition. This study can provide a reference for early warning and monitoring of short-term drought with rapid onset.

Recent studies on China’s arid and semi-arid regions, particularly the Tarim River Basin (TRB), have shown an increase in the intensity and frequency of extreme weather events. This research examines the link between meteorological droughts, as measured by the Standardized Precipitation Evapotranspiration Index (SPEI), and hydrological droughts, as indicated by the Standardized Runoff Index (SRI) and the Standardized Terrestrial Water Storage Index (STI), over various time scales. Historical data indicate that SPEI drought frequency (DF) was 14.3–21.9%, with prevalent events in the northern oases. SRI DF ranged from 9.0% to 35.8%, concentrated around the Taklamakan and Kumtag Deserts, while STI DF varied between 4.4% and 32.7%, averaging 15% basin-wide. Future projections show an increased DF of SPEI in deserts and a decrease in oases; SRI DF decreased in deserts but increased in oases. STI changes were more moderate. The study also found a higher risk of drought progression from SPEI to SRI in the southwestern and northeastern oases, exceeding 50% probability, while central and eastern TRB had lower risks. The western TRB and inner Taklamakan Desert faced higher risks of SPEI to STI progression, with probabilities over 45%, in contrast to the lower risks in the eastern and central oases. The concurrence of SRI/STI with moderate to extreme SPEI droughts led to a higher probability and area of SRI/STI droughts, whereas consistent SPEI types showed a reduced induced probability and extent of SRI/STI droughts. This study enhances the understanding of drought propagation from meteorological to hydrological droughts in the TRB and contributes to the prevention of hydrological drought to a certain extent.

Rhodiola L. has high nutritional and medicinal value. Little is known about the properties of its habitat distribution and the important eco-environmental factors shaping its suitability. Rhodiola coccinea (Royle) Boriss., Rhodiola gelida Schrenk, Rhodiola kirilowii (Regel) Maxim., and Rhodiola quadrifida (Pall.) Fisch. et Mey., which are National Grade II Protected Plants, were selected for this research. Based on high-resolution environmental data for the past, current, and future climate scenarios, we modeled the suitable habitat for four species by MaxEnt, evaluated the importance of environmental factors in shaping their distribution, and identified distribution shifts under climate change scenarios. The results indicate that the growth distribution of R. coccinea, R. kirilowii, and R. quadrifida is most affected by bio10 (mean temperature of warmest quarter), bio3 (isothermality), and bio12 (annual precipitation), whereas that of R. gelida is most affected by bio8 (mean temperature of wettest quarter), bio13 (precipitation of wettest month), and bio16 (precipitation of wettest quarter). Under the current climate scenario, R. coccinea and R. quadrifida are primarily distributed in Tibet, eastern Qinghai, Sichuan, northern Yunnan, and southern Gansu in China, and according to the 2070 climate scenario, the suitable habitats for both species are expected to expand. On the other hand, the suitable habitats for R. gelida and R. kirilowii, which are primarily concentrated in southwestern Xinjiang, Tibet, eastern Qinghai, Sichuan, northern Yunnan, and southern Gansu in China, are projected to decrease under the 2070 climate scenario. Given these results, the four species included in our study urgently need to be subjected to targeted observation management to ensure the renewal of Rhodiola communities. In particular, R. gelida and R. kirilowii should be given more attention. This study provides a useful reference with valuable insights for developing effective management and conservation strategies for these four nationally protected plant species.

In the context of climate warming, flash drought has become increasingly frequent, posing significant threats to agriculture, ecosystems, and the environment. Xinjiang, located in an arid and semi-arid region, necessitates a thorough investigation into the distinctions between flash drought and traditional drought, as well as an exploration of the driving forces behind both types of drought. In this study, soil moisture data from ERA5-Land were utilized to construct a framework for the identification of flash drought and traditional drought based on historical events. The Geodetector was employed to explore the factors that influence the spatial heterogeneity of these two drought forms. The findings illuminate that (1) in terms of spatial distribution, traditional drought predominated in southern Xinjiang, while flash drought exhibited greater prominence in northern Xinjiang. (2) Regarding changes in trends, both flash drought and traditional drought exhibited an increasing trend in frequency since the 1990s, with the frequency trend of flash drought passing the significance test (α ≤ 0.05). Additionally, the severity of both flash drought and traditional drought displayed a noteworthy and statistically significant increase within sliding windows ranging from 46 to 62 years. (3) Concerning the driving forces, precipitation emerged as the principal driving force behind both flash drought and traditional drought. Furthermore, human activities exerted a more substantial influence on traditional drought, and the interactions involving human activities had the potential to significantly amplify the explanatory power of the spatial heterogeneity for both drought types. (4) In terms of the drought risk, a notable variation in the risk of flash drought was observed across various ecological zones, with the highest risk occurring in mildly fragile ecological zones. Furthermore, when comparing the results from 1995 to 2019, the flash drought risk exhibited a marked increase in severely fragile ecological zones. This study enriches the understanding of the dynamics of flash drought and traditional drought in Xinjiang and carries important implications for enhancing the precision of drought monitoring and early warning systems.

Analyzing the sustainable development of a given region can provide an important reference and guide for future orientation. The study selects Turpan (including Gaochang District, Shanshan County, and Toksun County) in Xinjiang Uygur Autonomous Region of Northwest China as the study area and first investigates the essence of regional sustainable development. Based on the relevant data of the population, economy, and environment of Turpan from 2002 to 2018, we constructed an evaluation index system for three dimensions, namely, the population, economy, and environment, and analyzed them systematically. Specifically, we quantitatively calculated the comprehensive evaluation index, coupling degree, and coupling coordination degree of the sustainable development system of the study area. The study finds that Turpan has on some dimensions become increasingly sustainable, especially the economic development level has improved. The results show that the coupling coordination degree has increased from 0.3692 to 0.8894 during the period 2002–2018, which reflects the actual situation of Turpan and indicates that the proposed analysis method can effectively measure and evaluate the level of sustainable development in this region. Moreover, the study also puts forward main functional zoning of Turpan (i.e., Gaochang District as an optimized development zone, Shanshan County as a major agricultural production zone, and Toksun County as a key ecological function zone) and regional planning principles based on the population, economic, and environmental coupling analysis for the three jurisdictions in Turpan.

Water scarcity is an important factor limiting agricultural development in arid areas. Clarifying and evaluating the current situation of water resources in arid regions is helpful for decision-makers in the rational use of water resources. This study takes a typical arid region located at the edge of Taklamakan Desert-Hotan region as the study area. The water footprint (WF) of the Hotan region was calculated based on 20 years of data information from 2000–2019. An evaluation system was established using four aspects of the WF: structural indicators, efficiency indicators, ecological safety indicators, and sustainability indicators. The results show that the WF of the study area is mainly dominated by blue water consumption, with a proportion of 65.74%. The WF of crop production is larger than that of livestock production. The produced WF of grain crops is the highest of all products with a share of 44.21%. The increase in the local agricultural WF reached 53.18% from 2000 to 2019, but it was still lower than the amount of water available for agriculture. The evaluation results indicated that the region’s WF import dependency is lower than the global level, with an annual average self-sufficiency rate of 91.13% and an increase of 878.95% in the WF economic efficiency index. The agricultural WF produced in Hotan is exported in the form of trade, but the quantitative contribution is small and does little to relieve water stress in other regions. The agricultural water consumption was still within the range of local water resources that could be carried but only 6 years of sustainable water use, and the future development was not optimistic. With the ratio of produced WF to available water resources maintained at about 58%, the local available water resources should be above 43.21 × 108 m3 to initially ensure the sustainable use of water resources. There were 12 drought years in the study period, which are prone to droughts and high disaster levels. The drought-water scarcity systems behaved in three phases: 2000–2011 (uncoordinated level), 2012–2015 (transitional phase), and 2016–2019 (coordinated level). Water scarcity threatened by drought reduced. The occurrence of meteorological droughts was more related to natural factors while the changes in WF were mainly driven by socio-economic elements such as human activities.

Small mountain catchments usually lack hydrological monitoring and gauges. Therefore, in such areas, data on past flood and bank erosion are often missing, which makes assessing flood and erosion hazards very limited. We attempt to fill in this gap by dating individual flood and erosion events from growth disturbances produced by trees after their stems are tilted, and their roots are exposed and wounded by transported material. We aimed to develop a conceptual approach to integrate dendrochronology and 2D modelling for indicating and assessing past events of floods and bank erosion on a small mountain river Łomniczka, Sudeten mountains, Poland. We dated growth disturbances resulting from tilting of stems of spruce trees which grow on eroded riverbanks, i.e. tree-ring eccentricity and compression wood. We also dated disturbances resulting from the exposure of roots from under the soil cover, i.e. sudden decreases of cell lumen, and root injuries by debris transported by floods, i.e. scars and traumatic resin ducts. Dendrochronology allow to indicate the occurrence of 28 floods since the 1930s, including 11 floods when bank erosion was also recorded at study sites. The approach enables to identify rates of bank erosion during specific floods which ranged at study sites from 20 to 120 cm. The largest discharge was determined for the 1997 flood (106,7 m3 s−1), and the highest flow velocities were obtained for the 1930 floods (4.59 m/s). Results show that the highest shear stress occurred during the floods in 1943 and 1977 (510,3N/m2) and in 1997 flood (469.1 N/m2). We conclude that dendrochronology combined with 2D modelling allowed us to indicate past floods and bank erosion, and to prepare reliable inventories for analyses of flood and erosion hazard. The approach proposed in this paper can also be used as a tool for flood management, spatial management and planning.

The temporal variability and abrupt change analysis of temperature and precipitation in Turpan was investigated and examined based on a monthly data set of temperature, precipitation and drought indices (1960–2019) from three meteorological stations over the study area. The Yamamoto method, Mann–Kendall test, Standardized Precipitation Index (SPI), Standardized Precipitation Evaporation Index (SPEI), and Reconnaissance Drought Index (RDI) were applied to reveal temperature, precipitation and drought indices trends in their annual volumes. The conclusions were as follows: (1) in the past 60 years, the annual average temperature in the Turpan region has increased at a rate of 0.33 °C·(10a)−1. Whereas the temperature has accelerated since the 1980s, the annual average minimum temperature has increased more than the annual average maximum temperature, and the temperature difference between winter and summer has increased since the 1990s. (2) The inter-annual, inter-decadal and normal value changes in precipitation in the Turpan region and its three meteorological stations indicated a decreasing trend during 1960–2019. Though the normal value of summer and autumn precipitation decreased and increased as a whole, the normal values of spring, summer, winter and annual precipitation in the Turpan region displayed downward trends. (3) Abrupt changes in temperature were observed in the mid-1990s, and abrupt changes in precipitation were not obvious. (4) The SPI and RDI responded quickly to precipitation and temperature, and the overall characteristics of dry and wet trend changes were consistent. When the SPEI considered the combined effect of temperature and precipitation, the SPI and SPEI are better correlated, and the SPI and RDI are better correlated than the SPEI and RDI. On the whole, the occurrence of drought has obvious regional and seasonal characteristics. These conclusions not only provide scientific data for sustainable development in Turpan but also offer scientific information to further understand the trends and periodicity of climate change and drought conditions in hyper-arid regions around the world.

In Central Asia, the frequency and severity of droughts have a strong impact on the climate and lives of people. Therefore, it is essential to explore climate change, especially its impacts on the cycle and extent of drought occurrence. To determine drought conditions, the Palmer drought severity index (PDSI) is diffusely implemented and can be reconstructed using tree-ring chronologies. We collected Schrenk spruce (Picea schrenkiana) cores from six distinct areas in the Tianshan Mountains and used them to establish tree-ring chronologies. Correlation and reaction research revealed that the main impact on tree growth was humidity from previous years and the present growing season. To reconstruct the historical PDSI for the Tianshan Mountains, chronologies were applied. The reconstructed PDSI was considered to describe the climate change in the Tianshan Mountains because it captured severe drought events that were observed in other research findings. Furthermore, the spatial analysis results covered almost all of the Tianshan Mountains at 0.5° resolution. A large-scale drought event in the 1910s that was prevalent in the Tianshan Mountains was detected with tree rings. The extreme drought years of 1917, 1919, and 1944 detected on the chronologies were also specifically verified. A decadal analysis showed that the eastern and western Tianshan Mountains experienced continuous drought in the 1880s and during the 1810s ~ 1830s, the central and western Tianshan Mountains experienced continuous drought in the 1770s and 1640s, while it experienced a continuous wetting in the 1750s, and large-scale wetting occurred in Central Asia in the 2000s. This research offers a new perspective on the instability and spatial spread of drought in the Tianshan Mountains.

The eco-environment provides various spaces, conditions, and resources for human development, and their quality is a significant factor affecting sustainable development in a region. Most drylands face environmental fragility due to problems such as infertile land, scarce suitable living space, and a lack of resources. Therefore, investigating the temporal and spatial changes in the eco-environment of drylands is vital to developing them sustainably. This paper takes Hetian, which is located in the Tarim Basin of Western China and has typical features of an arid (or a hyper-arid) region, as the research area. The ecological index (EI) was used to construct a comprehensive ecological evaluation system, and five sub-indices (the biological richness index, vegetation coverage index, water network denseness index, land stress index, and pollution load index) were calculated to identify the quality and changes in the eco-environment of Hetian in 1995, 2009, and 2018. The results show that, from 1995 to 2018, the EI in Hetian showed a continuous downward trend (from 24.76 to 16.32), representing a change (ΔEI) of −8.44; this indicates significant deterioration in the quality of the local eco-environment. Large fluctuations in the EI also suggests that the environment in Hetian is very sensitive. In addition, the results revealed a degradation of Hetian, which includes a hyper-arid region.

Using historical data compiled by the Climate Research Unit, spatial and temporal analysis, trend analysis, empirical orthogonal function (EOF) analysis, and Taylor diagram analysis were applied to test the ability of 24 Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models to accurately simulate the annual mean surface air temperature in central Asia from the perspective of the average climate state and climate variability. Results show that each model can reasonably capture the spatial distribution characteristics of the surface air temperature in central Asia but cannot accurately describe the regional details of climate change impacts. Some of the studied models, including CNRM-CM5, GFDL-CM3, and GISS-E2-H, could better simulate the high- and low-value centers and the contour distribution of the surface air temperature. Taylor diagram analysis showed that the root mean square errors of all models were less than 3, the standard deviations were between 8.36 and 13.45, and the spatial correlation coefficients were greater than 0.96. EOF analysis showed that the multi-model ensemble can accurately reproduce the surface air temperature characteristics in central Asia from 1901 to 2005, including the rising periods and the fluctuations of the north and south inversion phases. Overall, this study provides a valuable reference for future climate prediction studies in central Asia.

A large-scale hydrological model (MIKE HYDRO) was established for the purpose of sustainable agricultural water management in the main stem Tarim River, located in northwest China. In this arid region, agricultural water consumption and allocation management are crucial to address the conflicts among irrigation water users from upstream to downstream. The results of model calibration indicated a close correlation between simulated and observed values. Scenarios with the change on irrigation strategies and land use distributions were investigated. Irrigation scenarios revealed that the available irrigation water has significant and varying effects on the yields of different crops. Irrigation water saving could reach up to 40% in the water-saving irrigation scenario. Land use scenarios illustrated that an increase of farmland area in the lower reach gravely aggravated the water deficit, while a decrease of farmland in the upper reaches resulted in considerable benefits for all sub-catchments. A substitution of crops was also investigated, which demonstrated the potential for saving considerable amounts of irrigation water in upper and middle reaches. Overall, the results of this study provide a scientific basis for decision-making on agricultural water consumption and allocation in the study area.

Plastic mulch film is widely used in agricultural production. However, there are very few studies on degradable mulch film. In order to investigate the effects of using degradable mulch film in arid regions on crop yield and water use efficiency, we used fully biodegradable mulch films on both maize and bare land cultivation experimental areas. The DeNitrification-DeComposition (DNDC) model was used to analyze changes in maize biomass in the future under different climate scenario models. We found that using fully biodegradable mulch film in an arid region had a positive effect on biomass yields. In 2015–2017, the annual maize biomass yield increased by 24.5%, 28.9%, and 32.9%, respectively. Hence, this method has expansion and promotion value. A comparison of the DNDC model simulated biomass yields and actual measured values found that the ranges of R2, root mean square error (RMSE), and model efficiency (ME) were 0.98–0.99, 0.38–0.86 mg C ha−1, and 0.80–0.98. This result shows that the DNDC model can accurately simulate changes in maize biomass in this region. Under the premise of a good model fit, future climate scenario model data were used to drive the DNDC model. The results showed that the possible range of maize biomass yields in the future is −6.5% to 10.3%, with the most probable range being 0.2–1.5%. Using future climatic conditions, our work suggests that degradable mulch films can increase water use efficiency by an average of 9.5%. The results of this study can be used to promote the use of degradable mulch films in arid regions, significantly improving sustainable agricultural development.

The Coupled Model Intercomparison Project Phase 5 (CMIP5) provides data, which is widely used to assess global and regional climate change. In this study, we evaluated the ability of 37 global climate models (GCMs) of CMIP5 to simulate historical precipitation in Central Asia (CA). The relative root mean square error (RRMSE), spatial correlation coefficient, and Kling-Gupta efficiency (KGE) were used as criteria for evaluation. The precipitation simulation results of GCMs were compared with the Climatic Research Unit (CRU) precipitation in 1986⁻2005. Most models show a variety of precipitation simulation capabilities both spatially and temporally, whereas the top six models were identified as having good performance in CA, including HadCM3, MIROC5, MPI-ESM-LR, MPI-ESM-P, CMCC-CM, and CMCC-CMS. As the GCMs have large uncertainties in the prediction of future precipitation, it is difficult to find the best model to predict future precipitation in CA. Multi-Model Ensemble (MME) results can give a good simulation of precipitation, and are superior to individual models.

Recent studies of soil carbon cycle in arid and semi-arid ecosystems demonstrated that there exists an abiotic CO2 absorption by saline-alkali soils (Aa) at desert ecosystems and suggested potential contributions of CO2 dissolution beneath deserts to the terrestrial ecosystems carbon balance. However, the overall importance of such soil CO2 uptake is still undetermined and its implications to the groundwater environment remain unaddressed. In this manuscript, a simple method is proposed for the direct computation of Aa from the total soil CO2 flux (Fa) as well as for the evaluation of Aa importance to Fa. An artificial soil-groundwater system was employed to investigate the implications to groundwater environment and it was found that soil CO2 uptake in deserts can contribute a possible influence on the evolution of the groundwater environment, providing that the absorbed CO2 largely remained in the soil-groundwater system.

Forested mountain slopes can be simultaneously affected by soil creep and landslide activity, both of which cause the tilting of tree stems, with the result that their dendrochronological record of tree-ring eccentricity and compression wood is potentially similar. There is a need to identify similarities and differences in these records and thus our research aimed to compare patterns of eccentricity and compression wood developed by trees under the impact of soil creep and landslides. We sampled trees growing on a landslide and creeping slopes in the Kamienne Mts., with 21 Norway spruce trees were sampled on each site. We found several main differences between the dendrochronological record of landslide activity and soil creep. On the landslide we found larger number of dendrochronological events, stronger and more variable eccentricity and a similar number of upslope and downslope events. On creeping slopes, upslope eccentricity events predominate, and the number of eccentricity events dated in all trees increases in time. We also compared the utility of eccentricity and compression wood for dating mass movements. They differ in their sensitivity to stem tilting. Thus, in analyses of landslide activity and soil creep activity, it is recommended to include both wood anatomy features. [ABSTRACT FROM AUTHOR]

Ecological changes in arid lands are often determined by the available water resources. For ecological protection, it is important to consider both hydrological and ecological processes. This paper presents a modeling approach to assess environmental changes and ecosystem services (ESS) in the largest inland river basin in China. Current water cycle and ecosystem protection measures were simulated, and future land use change scenarios were proposed accordingly. China is on the frontline of ecosystem protection and afforestation, but according to the simulation results, the available water resources cannot support more vegetation in its largest inland river basin. Without an additional water supply, 25.9 % of the existing area of natural vegetation will be degraded by 2050. A reduction in the area of cotton plantation did not substantially reduce farming incomes in the simulation. Drip irrigation and ecological flooding was effective for improving ESS, especially agricultural provisioning and riparian forest provisioning services, as well as regulating and supporting services. The assessment of ESS can achieve socio-economic and ecological benefits in a sustainable way, and also enable the impact of the complex environmental factors to be understood. The results can be used to evaluate current situations and develop creative solutions. [ABSTRACT FROM AUTHOR]

It is challenging for microrobots to fly using onboard energy due to the relatively heavy power supplies and inefficient actuators that are limited to a small size (mass less than 1000 mg and wingspan less than 100 mm). Inspired by the movement of jellyfish in nature (Physophora hydrostatica), herein, a microscale aerial vehicle FlyJelly is introduced, powered by onboard energy to achieve untethered flight. FlyJelly uses a balloon filled with helium to overcome self‐gravity and an actuator powered by electrostatic power to generate thrust. The balloon, heat sealed with two gold‐covered Mylar films, weighs 95.56 mg, provides 257.9 mg of buoyancy when filled with helium, and stores 19.457 × 10−3 J of energy when powered by 2400 V of direct current. The electrostatic actuator is composed of multiflapping units arranged radially and symmetrically, consuming only 0.3370 mW of power but generating a thrust of 0.2271 mN to drive the vehicle for flight. Benefiting from a design of distributed propulsion, FlyJelly is highly reliable and continues to work well even after the actuator is damaged. The milligram‐level weight, untethered flight with onboard energy, and high reliability make the prototype suitable for development as a long‐term remote exploration and search‐and‐rescue mission.

Recent studies of soil carbon cycle in arid and semi-arid ecosystems demonstrated that there exists an abiotic CO2 absorption by saline-alkali soils (Aa) at desert ecosystems and suggested potential contributions of CO2 dissolution beneath deserts to the terrestrial ecosystems carbon balance. However, the overall importance of such soil CO2 uptake is still undetermined and its implications to the groundwater environment remain unaddressed. In this manuscript, a simple method is proposed for the direct computation of Aa from the total soil CO2 flux (Fa) as well as for the evaluation of Aa importance to Fa. An artificial soil-groundwater system was employed to investigate the implications to groundwater environment and it was found that soil CO2 uptake in deserts can contribute a possible influence on the evolution of the groundwater environment, providing that the absorbed CO2 largely remained in the soil-groundwater system. [ABSTRACT FROM AUTHOR]

We report a novel electrostatic self-excited resonator driven by DC voltage that achieves variable velocity-position characteristics via applying the pre-tension/pre-compression constraint. The resonator consists of a simply supported micro-beam, two plate electrodes, and two adjustable constraint bases, and it can be under pre-compression or pre-tension constraint by adjusting the distance L between two constraint bases (when beam length l > L, the resonator is under pre-compression and when l < L, it is under pre-tension). The oscillating velocity of the beam reaches the maximum value in the position around electrodes under the pre-compression constraint and reaches the maximum value in the middle position between two electrodes under the pre-tension condition. By changing the constraint of the microbeam, the position of the maximum velocity output of the oscillating beam can be controlled. The electrostatic self-excited resonator with a simple constraint structure under DC voltage has great potential in the field of propulsion of micro-robots, such as active rotation control of flapping wings.