Tibetan Plateau In China Research Articles

Spatial Distribution Characteristics and Influencing Factors of Traditional Villages on the Tibetan Plateau in China.

The Tibetan Plateau is one of the world’s most extreme habitats and one of the most challenging ecosystems on the planet. Many multi-ethnic traditional villages have developed on the plateau over its long history, and are an essential component of human settlement. It is critical to research them, and it is also significant for China’s goals to make the Tibetan Plateau a distinctive ethnic cultural preservation site and a world tourist destination. While there have been limited studies focusing on villages in the entire Tibetan Plateau area, as a result, we aim to expand the field of research on the regional study of traditional villages and make progress in research throughout the Tibetan Plateau. The question addressed in this study is what the current characteristics of the distribution of traditional villages on the Tibetan Plateau are, and we attempt to propose suggestions for the preservation of traditional villages according to the distribution characteristics. Methods such as the closest neighbor index, kernel density estimates, and spatial autocorrelation analysis are used to investigate the characteristics of the spatial distribution of traditional Chinese villages on the Tibetan Plateau, as well as regression analysis of the factors that control this distribution. The findings indicate that traditional villages are unevenly distributed over the plateau, with fewer villages in the northwest and more in the southeast, showing an agglomeration type of distribution. The village distribution on provincial and municipal is uneven with a large step difference. Tibetans make up the majority of the population in the villages, but other ethnic groups are present at the margins of the plateau. The distribution of traditional villages shows “big scattered, small gather” characteristics, and one core cluster (the Hehuang Valley area of Qinghai Province) and five high-density areas (the western Sichuan Plateau; the Three Parallel Rivers area of Yunnan Province; the Yarlung Zangbo, Nyangqu, and Lhasa rivers (YZN) area of Tibet Province; the Yushu area of Qinghai Province; and the Gannan area of Gansu and Sichuan province). The natural environment has the strongest influence on the distribution of traditional villages, followed by human impacts, especially concerning the distribution of single and multi-ethnic villages, and socioeconomic factors, which have multiple influences.

Study on the Impact of the Doppler Shift for CO2 Lidar Remote Sensing

Atmospheric carbon dioxide (CO2) is recognized as the most important component of the greenhouse gases, the concentration of which has increased rapidly since the pre-industrial era due to anthropogenic emissions of greenhouse gases (GHG). The accurate monitoring of carbon dioxide is essential to study the global carbon cycle and radiation budget on Earth. The Aerosol and Carbon Detection Lidar (ACDL) instrument onboard the Atmospheric Environmental Monitoring Satellite (AEMS) was successfully launched in April 2022, which allows a new perspective to quantify the global spatial distribution of atmospheric CO2 with high accuracy. In this work, the impact of the Doppler shift on CO2 measurements for an integrated-path differential absorption (IPDA) light detection and ranging (lidar) system was evaluated to meet the weighted column-averaged mixing ratio of carbon dioxide (XCO2) measurement requirements of less than one part per million (ppm). The measurement uncertainties due to the Doppler shift were first evaluated in airborne IPDA observations. The result shows that most of the Doppler shift is in the range of 6–8 MHz, resulting in 0.26-0.39 ppm deviations in the XCO2 results. The deviations between the XCO2 retrievals and in situ measurements decreased to 0.16 ppm after the correction of the Doppler shift from 11:28:29 to 11:28:49 in the flight campaign. In addition, the online Doppler shift accounts for 98% of the deviations between XCO2 retrievals and in situ measurements. Furthermore, the impact of the Doppler shift on ACDL measurements is also assessed. The differences between the XCO2 retrievals with and without Doppler shift are used to quantify measurement uncertainties due to the Doppler effect. The simulations reveal that a pointing misalignment of 0.067 mrad can lead to a mean bias of about 0.30 ppm (0.072%) in the CO2 column. In addition, CO2 measurements are more sensitive to the Doppler shift at high altitudes for IPDA lidar, so the largest differences in the CO2 columns are found on the Qinghai–Tibet Plateau in China.

Spatio-Temporal Differences in Economic Security of the Prefecture-Level Cities in Qinghai-Tibet Plateau Region of China: Based on a Triple-Dimension Analytical Framework of Economic Geography.

The assessment of regional economic security (RES) is mainly based on the theoretical ideas of political economy and marginalism, and the research areas are mainly concentrated in European and American countries/regions, especially Eastern Europe. Taking the Qinghai–Tibet Plateau in China as an example, this paper constructs a triple-dimensional analytical framework, resources, and environmental–economic foundation-driving forces, based on the institutional approach of economic geography, with the purpose of making up for the deficiency of the extant literature, which pays little attention to regional characteristics and the dynamic mechanism concerning RES, and to provide a tool to identify key factors affecting RES. This paper obtained the main conclusions as follows. (1) The index of the economic security in the Qinghai–Tibet Plateau is on the rise, and the difference at the level of RES among cities is significant but tends to decrease. (2) There is a significant spatial autocorrelation among cities in the Qinghai–Tibet Plateau in terms of RES. The high-value areas are concentrated along the southeast edge, and the low-value areas are concentrated in the central areas of the west. (3) Despite lower weight values, the weakness of the economic foundation and the fragility of the ecological environment has increasingly hampered the improvement of the economic security in the Qinghai–Tibet Plateau. In terms of driving forces, it is the support of the central government and aid programs of other provinces that contributes to its economic development.

Snow detection in alpine regions with Convolutional Neural Networks: discriminating snow from cold clouds and water body

ABSTRACT Accurately monitoring the variation of snow cover from remote sensing is vital since it assists in various fields including prediction of floods, control of runoff values, and the ice regime of rivers. Spectral indices methods are traditional ways to realize snow segmentation, including the most common one – the Normalized Difference Snow Index (NDSI), which utilizes the combination of green and short-wave infrared (SWIR) bands. In addition, spectral indices methods heavily depend on the optimal threshold to determine the accuracy, making it time-consuming to find optimal values for different places. Convolutional neural networks ensemble model with DeepLabV3+ was employed as sub-models for snow segmentation using (Sentinel-2), which aims to distinguish clouds and water body from snow. The imagery dataset generated in this article contains sites in global alpine regions such as Tibetan Plateau in China, the Alps in Switzerland, Alaska in the United States, Southern Patagonian Icefield in Chile, Tsylos Provincial Park, Tatsamenie Peak, and Dalton Peak in Canada. To overcome the limitation of DeepLabV3+, which only accepts three channels as input features, and the need to use six features: green, red, blue, near-infraRed, SWIR, and NDSI, 20 three-channel DeepLabV3+ sub-models, were constructed with different combinations of three features and then ensembled together. The proposed ensemble model showed superior performance than benchmark spectral indices method, with mIoU values ranging from 0.8075 to 0.9538 in different test sites. The results of this project contribute to the development of automated snow segmentation tools to assist earth observation applications.

Dietary diversity and niche partitioning of carnivores across the Qinghai–Tibetan Plateau of China using DNA metabarcoding

Abstract Understanding predator guild resource use is vital for carnivore species preservation and ecosystem function in high-altitude landscapes. We describe the dietary composition, similarity, and niche overlap for seven carnivore species across three regions of the Qinghai–Tibetan Plateau (Qilian Shan, East Burhanbuda Mountain, Yushu) using DNA metabarcoding of 760 scat samples. Analyses found 33 unique prey items representative of the classes Mammalia, Aves, and Actinopterygii. Blue sheep (Pseudois nayaur) and pika (Ochotona sp.) were most frequently detected. Livestock in carnivore diets ranged from 4% to 7% depending on site, but accounted for 21.7% of Tibetan wolf (Canis lupus) diet. Eurasian lynx (Lynx lynx), Tibetan fox (Vulpes ferrilata), Pallas’s cat (Otocolobus manul), and snow leopard (Panthera uncia) had highly uneven diets. Intraguild predation of mesocarnivores by apex carnivores was found. Analysis of dietary niche overlap using Pianka’s index showed that overlap was significantly greater than expected among all carnivores examined and between apex and mesocarnivores, though significant correlations between carnivore body mass and prey body mass suggested broad separation in consumed prey. Snow leopard and Tibetan wolf diets were consistently the most similar of any two given species pairs. This study provides evidence of high dietary overlap. Protection for species consumed by a wide variety of carnivores will benefit predator guilds in the area and assist in maintaining the relatively low frequency of livestock predation. This work provides insight into the dynamics of carnivore guilds living in an area that has worldwide impacts, and methods herein could be applied on global scales for conservation efforts.

Evaluating the supply and demand of cultural ecosystem services in the Tibetan Plateau of China

ContextIn the Tibetan Plateau (TP), the supply of cultural ecosystem services (CESs) is unique, and the demand for CESs is gradually increasing with rapid urbanization. Evaluating the relationship between the supply and demand for CESs is critical for guiding regional sustainable development. However, due to the difficulty in obtaining empirical data in the high altitude and complex topography of the TP, relevant research is still lacking.ObjectivesThe objective of this study was to develop an approach to address the difficulty of obtaining the empirical data on the TP and to evaluate the relationship between the supply and demand for CESs.MethodsTaking the Qinghaihu–Huangshui basin as an example, we combined the SolVES (Social Values for Ecosystem Services) model and social media big data to evaluate the supply and demand for CESs in the TP.ResultsOur results showed that the combined method can effectively evaluate the supply and demand for CESs in the basin, and can be used for other remote regions. The supply and demand for CESs in the basin exhibited obvious spatial mismatch. Among the two types of mismatch, in the areas of high supply and low demand of CESs, residents’ subjective well-being (SWB) were substantially lower. Being far away from central city was an important reason for the high supply and low demand of CESs.ConclusionsEstablishing and improving the transportation system connecting central cities with other counties is encouraged to utilize the rich cultural and tourism resources of the TP, as well as enhance the SWB and promote regional sustainable development.

Effects of operational sex ratio and male density on size-dependent mating in Minshan’s toads, Bufo minshanicus, on the Tibetan Plateau of China

Abstract In many animal species, an increase in the operational sex ratio (OSR), density or a combination of both should lead to more intensive competition among individuals of the more abundant sex. To test this, we examined pairing patterns of Minshan’s toad (Bufo minshanicus) from six populations between 2008 and 2015 along the eastern Tibetan Plateau in south-west China. OSRs in breeding aggregations of Minshan’s toad are normally male biased and males actively compete with each other for acquisition and retention of mates. We found evidence that deviations from random mating by size varied between populations and between years according to the magnitude of the OSR and male density. Larger males were generally more successful in pairing than smaller males when the OSR was slightly male biased and male density was high. However, the resulting size-disproportionate mating was more evident when OSR was closer to 1.99, indicating a positive correlation with the intensity of aggressive scramble competition. Thus, the intensity of male-male competition may partly explain variation in size-disproportionate mating among populations.

Experimental Study on the Effects of Freeze–Thaw Cycles on Strength and Microstructure of Xining Region Loess in China

Loess, a collapsible soil, is widely distributed in the Qinghai–Tibet Plateau in China. In the meantime, loess is a sustainable and green building material that is widely used in traditional residential buildings. However, previous studies have focused on the properties of loess itself, ignoring the influence of climatic conditions on loess buildings, as well as a series of engineering problems such as soil spalling caused by freezing and thawing, cold cracks in walls, and settlement deformation of foundation. This research presents a series of laboratory tests on both undisturbed and remolded loess. The tests investigated changes in the unconfined compressive strength (UCS) of both types of loess after different freeze–thaw cycles. The freeze–thaw-induced changes to the internal structures of the loess were also investigated using a scanning electron microscope (SEM) and X-ray diffraction test (XRD). The test results showed that: (1) with increasing freeze–thaw cycles, the UCS of both the undisturbed and remolded loess appeared to first increase and then decrease, and the stress–strain curves showed a stronger strain-softening tendency. (2) The compressive strength of undisturbed loess is higher than remolded loess. (3) SEM analysis showed that the large particles inside the loess sample were gradually broken down into small particles, which led to an accumulative increase in fine particles and a decrease in the porosity. With the increase in the number of freeze–thaw cycles, the particles inside the soil become denser, and the strength increases. (4) Freezing and thawing have less effect on loess minerals. (5) The conclusion can provide a reference value for the protection of loess buildings in Qinghai and the management of freeze–thaw disasters.

Potential geographical distribution of Stipa purpurea across the Tibetan Plateau in China under climate change in the 21st century

Stipa purpurea ( S. purpurea ), a dominant herbage resource in alpine steppe, has an important impact on animal husbandry and the maintenance of natural environmental stability in the Tibetan Plateau (TP). As a hot spot of global warming, the TP has been greatly affected by climate change. Based on the MaxEnt model, we simulated the potential habitat changes of S. purpurea on the TP in the 21st century using 197 distribution records combined with current (2000–2018) and future (2021–2100) climate data. We also analyzed the critical factors influencing habitat distribution and driving habitat change. The results showed that the MaxEnt model performed well, with the area under the curve (AUC) value of training data and test data being 0.845 and 0.722, respectively. Annual precipitation, elevation, and annual average temperature were identified as the most critical environmental factors shaping the potential distribution of S. purpurea , and temperature was identified as the most critical factor driving S. purpurea habitat change. Under the current climate, the potential habitat area of S. purpurea was 55.15 × 10 4 km 2 , mainly distributed in the Eastern Qinghai-Qilian montane steppe, Southern Tibet montane shrub-steppe, and Ngari montane desert. By the end of the 21st century, the potential habitat area of S. purpurea showed an overall increasing trend, under two shared socio-economic pathways (SSP245 and SSP585) was 87.37 × 10 4 km 2 and 57.80 × 10 4 km 2 , respectively. A comparison of warming scenarios indicated that warming had a positive effect on the distribution of S. purpurea within a certain temperature range, but continued warming would limit distribution ranges. In response to climate warming in the 21st century, potential habitats of S. purpurea will shift northwestward and to higher altitudes. These results will provide a reference for implementing long-term conservation and management strategies on the TP and similar regions . • Species distribution modeling was used to predict the distribution of S. purpurea . • The “BioVars” package was used to calculate 19 bioclimatic variables. • Temperature contributed most to driving habitat redistribution of S. purpurea . • Warming had a positive effect on S. purpurea within a certain range. • Habitats of S. purpurea will shift northwestward and to higher altitudes.

Climate variability and change in Tibetan Plateau within a warming climate

Global warming has become a subject of concern with an increasing number of natural disasters under the excessive emission of greenhouse gasses, influencing many sectors of environment, society, and economy. Likewise, the climate of the Tibetan Plateau region (known as “the roof of the world”) is closely related to global warming. Yet, the variation and prediction of climate in Tibetan Plateau remain unresolved. The purpose of this research is to diagnose and forecast the climate change in Tibetan Plateau in China within the context of global warming based on surface temperature and precipitation data. Specifically, the results suggest that global warming closely affects the rising trend of the average temperature of the Tibetan Plateau, while the average precipitation of the Tibetan Plateau is also producing an increasing trend with the increase of temperature. In order to prevent the environmental ecosystem of the Tibetan Plateau from being destroyed by severe climate change under the future influence of global warming, the government should regulate greenhouse gas emissions to ensure that global warming does not worsen.

Temperature sensitivity of soil enzyme kinetics under N and P fertilization in an alpine grassland, China

Soil nutrient cycling can be best studied by supplementing the soil with N and P fertilizers. Soil enzyme kinetic parameters (Vmax and Km) can be used to reflect the maximum reaction rates and affinities of soil enzymes. However, how N and P fertilizers affect the temperature sensitivity of soil enzyme kinetics is poorly understood. Therefore, our study investigated the response of soil enzyme kinetic temperature sensitivity relevant to C, N, and P cycles based on a 9-year fertilization (N and P) experiment performed in an alpine grassland on the Qinghai–Tibetan Plateau in China. Our results showed the following: N and P addition positively affected the Km of β-glucosidase (BG); P and NP interaction significantly increased the Km of phosphatase (AP), indicating that N and P addition significantly negatively affected the substrate affinity of soil enzymes. The temperature sensitivity of Michaelis–Menten kinetics was different for different enzymes. N and P fertilization decreased the temperature sensitivity of Km of BG but increased the temperature sensitivity of the Km of N-acetyl-glucosaminidase (NAG) and AP. In our study, P and NP fertilization increased the temperature sensitivity and activation energy of the Vmax of BG, indicating that P elements promoted the secretion of more extracellular enzymes by soil microbes to cope with temperature changes. The enzymes involved in the soil N and P cycle responded to the exogenous N and P through increases and decreases in the temperature sensitivity of the Km and Vmax, respectively. This study is crucial for investigating the impact of nutrient input on soil ecosystem functions under future climate warming conditions.

Dynamic response characteristics of heliostat under hail impacting in Tibetan Plateau of China

Heliostats are prone to be destroyed under the action of thunderstorm and hail in the wild. Many studies on heliostat mainly focused on the effect of wind load, while it is a lack of in-depth understanding on the dynamic responses of heliostats under hail impacting. This study performs the dynamic response of heliostat under hail impacting in Tibetan Plateau of China by numerical simulation. A hail dynamic constitutive model considering strain rate effect and brittle fracture behavior was established and verified based on historical hail statistics, and the effects of hail impacting position, hail size, elevation angle and thickness of heliostat on the dynamic response characteristics were analyzed. The research results demonstrate that the impact position has a significant influence on the displacement of heliostat, but a little effect on the maximum stress. The stress and displacement of the heliostat increase with the increase of hail size, while decrease with the increase of the elevation angle and thickness of heliostat. When the hail diameter increases to 30 mm, the maximum principal stress of heliostat exceed its tensile strength. The results are useful and interesting to researchers who can reference the obtained results to predict the heliostat safety under hail impacting.

Diverse Responses of Phenology in Multi-Grassland to Environmental Factors on Qinghai–Tibetan Plateau in China

Studying grassland vegetation growing seasons’ spatial patterns and their environmental controls are crucial to promoting vegetation ecological restoration, formulating effective disaster prevention and reduction measures and building a stable ecological barrier. However, multi-grassland phenological factors are different, and this has not been well studied before. In this paper, the spatiotemporal patterns of the start of the growing season (SOS) and the end of growing season (EOS) in the grassland were investigated using the Normalized Difference Vegetation Index (NDVI) on the Qinghai–Tibetan Plateau (QTP) from 2000 to 2019. At the same time, we analyzed the environmental factors (including extreme, mean climate, drought, solar radiation, etc.) regulating grassland phenology under the ongoing conditions of climate change. The results show that the SOS appeared first in mountain meadow, shrub tussock, temperature steppe and desert, and then in alpine steppe and alpine meadow, showing a significant advancing tendency in all types. The EOS occurred first in the temperature steppe, alpine steppe and alpine meadow, and then in the mountain meadow, shrub-tussock and desert. Further analysis indicated that reductions in the annual lowest value of daily min temperature (TNN), annual highest value of daily min temperature (TNX) and temperature vegetation dryness index (TVDI), and increases in annual maximum consecutive 5‐day precipitation (RX5day) advanced the grassland spring phenology, whereas the increase in solar radiation (SR) delayed the grassland spring phenology. We also found that the decrease in TVDI and TNN and the increase in yearly mean value of temperature (MAT_MEAN), yearly mean value of daily maximum temperature (MAT_MAX) and yearly mean value of daily minimum temperature (MAT_MIN) advanced the autumn phenology. The EOS and its change rate advanced and increased with increasing altitude, respectively.

Application of microcontroller and Blynk for cultured cordyceps

Cordyceps is a precious herb in the world; it was discovered in the Tibetan Plateau of China. It has many good uses for human health as used to replenish the kidney and soothe the lung for the treatment of fatigue, night sweating, homosexualities, hyperglycemia, hyperlipidemia, asthenia after severe illness, respiratory disease, renal dysfunction and renal failure, arrhythmias, and other heart diseases, and liver disease. Due to the production of natural cordyceps exploited each year is increasingly scarce and depleted in recent times. Therefore currently, the cultivation of this herb has been applied to meet the higher demand of the market. Using microcontrollers to monitor and manage environmental parameters such as light, temperature and humidity, and soil moisture, we have produced medicinal substances from cordyceps of similar high quality as natural products.

A Combined Optimization‐Assimilation Framework to Enhance the Predictive Skill of Community Land Model

AbstractLand Surface Model (LSM) predictions are affected by unknown parameters, uncertain meteorological forcings, inaccurate initial conditions, and incomplete process representation. While parameter optimization (PO) algorithms have been used to estimate the model parameter for best model performance, the use of data assimilation (DA) has been receiving increased prominence to characterize the uncertainties in such models. However, it is still an open question that how DA techniques can be used together with PO algorithms to enhance the performance of LSMs for different applications. In this study, a combined framework composed of the PO algorithm—Adaptive Surrogate Modeling Based Optimization (ASMO) and the DA algorithm—Evolutionary Particle Filter with Markov Chain Monte Carlo (EPFM), is used to improve the soil moisture (SM) estimates of Community Land Model (CLM) across the Tibetan Plateau in China. The SM data from the Soil Moisture Active Passive satellite are used as the benchmark data for model improvement. To demonstrate the usefulness and effectiveness of the proposed approach, the simulated SM values are validated against the SM observations collected from the in situ networks in the Tibetan Plateau, China. The findings revealed that the joint application of ASMO and EPFM algorithms results in more accurate and reliable SM estimates of CLM compared to when they are solely employed. This study suggests that the combined optimization‐assimilation framework can be utilized for improving the predictive skill of the other large‐scale complex LSMs while accounting for the uncertainties associated with both model parameters and state variables.

Habitat Use and Activity Patterns of Mammals and Birds in Relation to Temperature and Vegetation Cover in the Alpine Ecosystem of Southwestern China with Camera-Trapping Monitoring.

Simple SummaryThe Wolong National Nature Reserve in Sichuan province covers a unique mountainous ecosystem located on the eastern border of the Tibetan Plateau in China. We applied a popular non-invasive observational method, i.e., infrared-triggered camera trapping, to gain thousands of photographs of wildlife to monitor biodiversity over three years. Combined with data on the local abiotic factors, our integrative statistical analysis identified the key environmental drivers, i.e., temperature and vegetation, affecting the distribution and abundance of mammals and birds in the reserve. All species were classified into three main types by their tolerance of or fondness for different environmental conditions. The detectability of each species by camera trapping was quantified and ranked to provide insights on each species’ relative abundance in the area.The high-altitude ecosystem of the Tibetan Plateau in China is a biodiversity hotspot that provides unique habitats for endemic and relict species along an altitudinal gradient at the eastern edge. Acquiring biodiversity information in this area, where the average altitude is over 4000 m, has been difficult but has been aided by recent developments in non-invasive technology, including infrared-triggered camera trapping. We used camera trapping to acquire a substantial number of photographic wildlife records in Wolong National Nature Reserve, Sichuan, China, from 2013 to 2016. We collected information of the habitat surrounding the observation sites, resulting in a dataset covering 37 species and 12 environmental factors. We performed a multivariate statistical analysis to discern the dominant environmental factors and cluster the mammals and birds of the ecosystem in order to examine environmental factors contributing to the species’ relative abundance. Species were generalized into three main types, i.e., cold-resistant, phyllophilic, and thermophilic, according to the identified key environmental drivers (i.e., temperature and vegetation) for their abundances. The mammal species with the highest relative abundance were bharal (Pseudois nayaur), Moupin pika (Ochotona thibetana), and Himalayan marmot (Marmota himalayana). The bird species with highest relative abundance were snow partridge (Lerwa lerwa), plain mountain finch (Leucosticte nemoricola), Chinese monal (Lophophorus lhuysii), and alpine accentor (Prunella collaris).

Spatiotemporal variation and periodic evolution characteristics of groundwater in the Xining area of China, eastern Qinghai–Tibet Plateau

As an important water source, groundwater profoundly influences global human survival and production. The spatiotemporal characteristics of groundwater and the periodic variation law of different time scales must be analyzed to understand the dynamic situation of this resource and to provide scientific guidance for its rational utilization and management. In this study, the temporal and spatial variability and periodicity of groundwater level in the Xining region of eastern Qinghai–Tibet Plateau in China were studied using the traditional statistical method, geographic information system, and Morlet wavelet analysis. Results show that the groundwater dynamics in the study area are mainly controlled by three factors, namely, the amount of river water infiltration, discharge from groundwater, and artificial exploitation. These factors can be divided into three dynamic types, namely, hydrological, hydrological exploitation, and runoff discharge, according to their combination relationship. From 1980 to 2020, the groundwater depth in Xining initially increased before stabilizing and eventually decreasing. As revealed in the spatial variability analysis, groundwater depth demonstrates a huge spatial difference with a moderate spatial variation intensity across different periods. Moreover, the spatial correlation of groundwater in the abundant season is lower than that in the dry season mainly due to increasing artificial exploitation. Meanwhile, the Kriging interpolation of the spherical model in the geographic information system reveals that the groundwater in Xining is deep in the south and east and shallow in the north and west. From the 1960s to 2000s, the inter-annual groundwater in the region continuously declined due to chronic overexploitation, with a maximum cumulative depth of 15 m. Afterward, the amount groundwater extraction was further reduced, and the amount of rainfall significantly increased in recent years. Accordingly, the cone of depression underwent an evolutionary process involving periods of expansion, stability, and shrinkage. The annual groundwater level in most monitoring wells within the study area demonstrated the same multi-year scale time-variation characteristics with an evident regular periodic variation on the 9-14a and 17-25a time scales according to the results of the Morlet wavelet transform analysis. The temporal sequence of groundwater from 1980 to 2020 had two main periods, namely, 12a and 21a. According to these time scales, the groundwater level in Xining will continue to increase in the short term, which provides a scientific theoretical basis for the long-term sustainable development of groundwater resources and government decision-making.

Evolution of sexual dimorphism in an endemic toad of the Qinghai–Tibet plateau fails to obey Rensch’s rule

According to Rensch's rule, sexual size dimorphism (SSD) decreases with increasing body size in species where females are larger than males, whereas SSD increases with body size when males are larger than females. In this study, we examined body size from 15 populations of Bufo minshanicus in the Qinghai–Tibet plateau in China. We estimated the age of the individuals from eight populations to evaluate Rensch's rule and possible causes of variation in SSD. After or before correcting male and female body size for age differences, the patterns of SSD failed to obey Rensch's rule or its inverse, even though fecundity selection in toads tends to favor larger female body size. We also found that the degree of SSD was positively correlated with the operational sex ratio in the field across B. minshanicus populations. Thus, sexual and fecundity selection play an equal role driving the evolution of SSD within toads. In addition, sex-specific growth rate and age structure explain part of the variation observed in SSD across populations.

Co-Seismic Surface Rupture and Recurrence Interval of Large Earthquakes along Damaoyaba-Litang Segment of the Litang Fault on the Eastern Margin of the Tibetan Plateau in China

Co-Seismic Surface Rupture and Recurrence Interval of Large Earthquakes along Damaoyaba-Litang Segment of the Litang Fault on the Eastern Margin of the Tibetan Plateau in China

Sensitivity and future exposure of ecosystem services to climate change on the Tibetan Plateau of China.

ContextClimate change has imposed tremendous impacts on ecosystem services. Recent attempts to quantify such impacts mainly focused on a basin or larger scale, or used limited time periods that largely ignore observations of long-term trends at a fine resolution, thereby affecting the recognition of climate change’s effect on ecosystem services.ObjectivesThis study conducts a detailed and spatially explicit recognition of climate change’s effect on ecosystem services and provides an intuitive map for decision-making and climate change adaptation planning.MethodsWe used long-term time series of ecosystem service assessments and various future climate scenarios to quantify the sensitivity and future exposure of ecosystem services to climate change on the Tibetan Plateau.ResultsCarbon sequestration (CS) and habitat quality experience significant growth, while water retention did not show any trend. Sensitivity patterns of these ecosystem services vary largely. For CS, more than half of the pixels showed a positive sensitivity to climate change, even though the degree of sensitivity is not high. There is substantial spatial heterogeneity in the exposure of ecosystem services to future climate changes, and high levels of future climate change increase the intensity of exposure.ConclusionsThis study illustrates the complex spatial association between ecosystem services and climatic drivers, and these findings can help optimize local response strategies in the context of global warming. For example, the existing protected areas have notable conservation gaps for disturbance of future climate change on ecosystem services, especially in the southeastern part of the study area.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10980-021-01320-9.