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The controlled synthesis of hollow structure transition metal compounds has long been a very interesting and significant research topic in the energy storage and conversion fields. Herein, an ultrasound-assisted chemical etching strategy is proposed for fabricating concave Ni(OH)2 nanocubes. The morphology and composition evolution of the concave Ni(OH)2 nanocubes suggest a possible formation mechanism. The as-synthesized Ni(OH)2 nanostructures used as supercapacitor electrode materials exhibit high specific capacitance (1624 F g−1 at 2 A g−1) and excellent cycling stability (77% retention after 4000 cycles) due to their large specific surface area and open pathway. In addition, the corresponding hybrid capacitor (Ni(OH)2//graphene) demonstrates high energy density (42.9 Wh kg−1 at a power density of 800 W kg−1) and long cycle life (78% retention after 4000 cycles at 5 A g−1). This work offers a simple and economic approach for obtaining concave Ni(OH)2 nanocubes for energy storage and conversion. [ABSTRACT FROM AUTHOR]

Multimodal communication in animals is common, and is particularly well studied in signals that include both visual and auditory components. Multimodal signals that combine acoustic and olfactory components are less well known. Multimodal communication plays a crucial role in agonistic interactions in many mammals, but relatively little is known about this type of communication in nocturnal mammals. Here, we used male Great Himalayan leaf-nosed bats Hipposideros armiger to investigate multimodal signal function in acoustic and olfactory aggressive displays. We monitored the physiological responses (heart rate [HR]) when H. armiger was presented with 1 of 3 stimuli: territorial calls, forehead gland odors, and bimodal signals (calls + odors). Results showed that H. armiger rapidly increased their HR when exposed to any of the 3 stimuli. However, the duration of elevated HR and magnitude of change in HR increased significantly more when acoustic stimuli were presented alone compared with the presentation of olfactory stimuli alone. In contrast, the duration of elevated HR and magnitude of change in HR were significantly higher with bimodal stimuli than with olfactory stimuli alone, but no significant differences were found between the HR response to acoustic and bimodal stimuli. Our previous work showed that acoustic and chemical signals provided different types of information; here we describe experiments investigating the responses to those signals. These results suggest that olfactory and acoustic signals are non-redundant signal components, and that the acoustic component is the dominant modality in male H. armiger , at least as it related to HR. This study provides the first evidence that acoustic signals dominate over olfactory signals during agonistic interactions in a nocturnal mammal. [ABSTRACT FROM AUTHOR]

Rydberg atoms can serve as an atomic radio frequency receiver for digital and analog information transmission. In this paper, a ladder-type electromagnetically induced transparency system is prepared in a room temperature cesium atomic vapor cell. Microwave electric fields in the Ku band at a frequency of 12.52 GHz and the Ka band at a frequency of 39.80 GHz are used as two-channel communication carriers to demonstrate concurrent information transmission. Analog and digital communications are demonstrated by performing audio and pseudo-random binary sequence signal transmission, respectively. The dynamic range of the proposed system is ∼50 dB, and the communication bandwidth is more than 10 MHz. The obtained results demonstrate the fundamental principles of two- or multi-band communication systems based on different Rydberg final states. [ABSTRACT FROM AUTHOR]

Siwu decoction (SWD) is widely used in gynecological diseases, such as peripheral menopause syndrome, premature ovarian failure, and menstrual disorder. However, the mechanism of SWD on postmenopausal osteoporosis (PMOP) remains unclear. To discover the phytoestrogenic osteoprotective effect of SWD on PMOP. The potential mechanism of SWD on PMOP was filtered through network pharmacology research. The potential mechanism was verified in MC3T3-E1 cell lines in vitro. CCK8 assay was conducted to assess cell proliferation and the expressions of ER/PI3K/AKT pathway were analyzed using Western blot. Female F-344 rats were chosen to set up the PMOP model. The osteoprotective effect of SWD in vivo was evaluated using Hematoxylin-eosin staining, TRAP staining, Goldner staining and DXA. The potential mechanism was verified in vivo through Western blot and immunohistochemistry. RT-qPCR was conducted to unveil the expressions of osteogenesis genes. Network pharmacology research showed that ER/PI3K/AKT pathway may be the potential mechanism of SWD on PMOP. SWD promoted the proliferation of osteoblasts and regulated the protein expressions of ER/PI3K/AKT pathway in vitro. SWD improved the morphological structure, bone mineralization and bone mineral density of femurs and suppressed osteoclastogenesis in PMOP rat model via ER/PI3K/AKT pathway in vivo. In addition, SWD regulated the mRNA expressions of osteogenesis-related genes. SWD exerts a phytoestrogenic osteoprotective on PMOP by regulating ER/PI3K/AKT pathway, which marks it as a valuable medicine or supplement of PMOP. [Display omitted] • SWD promotes the proliferation of osteoblasts and regulates the protein expressions of ER/PI3K/AKT signaling pathway. • SWD reverses the deterioration of bone tissue in postmenopausal osteoporosis. • SWD regulates the expressions of osteogenesis-related genes. • SWD exerts a phytoestrogenic osteoprotective effect on postmenopausal osteoporosis via ER/PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]

As installed wind power capacity continues to rise, the cost of onshore wind power generation in China has fallen, far exceeding the world average. The purpose of this study is to explore the main factors affecting onshore wind power in China and to identify ways to reduce costs. So as to reduce the cost of wind power and promote the large-scale grid-connected use of wind power. Therefore, this paper summarizes various factors that affect the development of onshore wind power. We also provide a comprehensive and repeatable MFLC (multi-factor learning curve) method to evaluate the factors affecting the cost of onshore wind power. Subsequently, the learning rates of various factors are calculated using this method. The results show that empirical learning by increasing installed capacity/generation, improving technology and selecting sites which are rich in natural resources, and appropriately reducing capital investment and material prices can significantly reduce the LCOE (levelized cost of electricity) of onshore wind power in China. Compared with wind power giants of the United States and Germany, the reduction in the cost of onshore wind power generation in China is more dependent on inputs such as capital investment and raw materials, while experience plays a relatively minor role. The ability to make full use of natural resources and to convert wind energy into electricity more efficiently is crucial to reducing the cost of wind power. • This paper summarizes various factors that affect the development of onshore wind power. • A comprehensive and repeatable MFLC method is built in this paper. • The learning rates of various factors are calculated. [ABSTRACT FROM AUTHOR]

We investigated spatial and temporal variations in the accumulated growing degree-days (AGDD) requirement for spring vegetation green-up onset on the Tibetan Plateau (TP) during the rapid warming period of 1998–2012, which is essential for understanding and modeling the spring vegetation phenological responses to climate change. Annual green-up date was determined by using a satellite-derived normalized difference vegetation index. The annual AGDD requirement was then determined as the sum of daily mean air temperatures above 0 °C over the dormancy period. Linear regression between the AGDD requirement and year was used to determine its temporal trend. Partial correlation analysis was used to assess factors controlling inter-annual variations in the AGDD requirement. We found the AGDD requirement was significantly different for different vegetation types and showed large spatial variations ranging from a few °C-days in cold and wet areas to more than 1000 °C-days in warm and dry areas of the TP. Despite the rapid warming and subsequent earlier green-up date, the AGDD requirement did not increase significantly over the period 1998–2012. Interestingly, we found that the inter-annual variations in AGDD requirement were extensively driven by the number of chilling days, while precipitation sum and insolation affected the AGDD requirement in limited areas. Although the winter warming reduced chilling accumulation on the TP, the AGDD requirement for vegetation green-up onset did not necessarily increase over 1998–2012, being insensitive to decline in the chilling accumulation. This suggested that the chilling requirement to break vegetation dormancy might be still fulfilled. In other words, the winter warming might not substantially affect the vegetation green-up process, since the reduction in chilling accumulation may not affect the dormancy break. However, the negative temporal correlation between the AGDD requirement and number of chilling days indicates that continued future warming may lead to a deficiency in chilling and thus an increase in AGDD requirement. [ABSTRACT FROM AUTHOR]

Highlights from the article: Plant spring phenology is receiving increasing attention owing to the recognition of its high sensitivity to ongoing climatic warming [1]. Piao et al. [14] found that spring phenology was triggered more by daytime temperature than by nighttime or daily average temperature, but the spring carbon uptake was weakened with the increase of temperature [15]. Considering difference among methods in determining spring phenology, we retrieved spring phenology using five different approaches [5], including Gauss, Spline, HANTS, Polyfit, and Timesat (see Ref. [5] for details).

ABSTRACT The vegetation green-up date ( GUD) is widely expected to advance to an earlier date in the year in response to increasing spring temperature. However, although it is well known that climatic warming has been more intensive at higher latitudes than at lower latitudes in the Northern Hemisphere, it is not known whether this greater climatic warming at higher latitudes has led to a greater advance of vegetation GUD during the past few decades. We have first determined GUD from the satellite-derived greenness vegetation index for all the vegetated land between 30 and 75°N from 1982 to 2008, and then investigated the latitudinal pattern of the inter-annual trend of GUD and its relation to pre-season temperature. The results show a generally greater GUD advance in lower latitudes, in spite of the faster increase in pre-season temperature in higher latitudes. We find that 88% of the latitudinal variability in the GUD trend can be explained by the sensitivity of the GUD response to pre-season temperature. The GUD change has also resulted in a northward shift of GUD isolines by 1°-4° between 50 and 65°N during the period. These findings highlight the sensitivity of vegetation response to temperature in shaping the spatial pattern of spring phenological change and suggest that temperate ecosystems may experience greater phenological change if the current latitudinal pattern of climatic warming continues. [ABSTRACT FROM AUTHOR]

The change in spring phenology is recognized to exert a major influence on carbon balance dynamics in temperate ecosystems. Over the past several decades, several studies focused on shifts in spring phenology; however, large uncertainties still exist, and one understudied source could be the method implemented in retrieving satellite-derived spring phenology. To account for this potential uncertainty, we conducted a multimethod investigation to quantify changes in vegetation green-up date from 1982 to 2010 over temperate China, and to characterize climatic controls on spring phenology. Over temperate China, the five methods estimated that the vegetation green-up onset date advanced, on average, at a rate of 1.3 ± 0.6 days per decade (ranging from 0.4 to 1.9 days per decade) over the last 29 years. Moreover, the sign of the trends in vegetation green-up date derived from the five methods were broadly consistent spatially and for different vegetation types, but with large differences in the magnitude of the trend. The large intermethod variance was notably observed in arid and semiarid vegetation types. Our results also showed that change in vegetation green-up date is more closely correlated with temperature than with precipitation. However, the temperature sensitivity of spring vegetation green-up date became higher as precipitation increased, implying that precipitation is an important regulator of the response of vegetation spring phenology to change in temperature. This intricate linkage between spring phenology and precipitation must be taken into account in current phenological models which are mostly driven by temperature. [ABSTRACT FROM AUTHOR]

The reliability test track has much stronger excitations on vehicles than common roads, and its amplitude distribution often presents obvious non-Gaussian features; But the existing time-domain road excitation modeling methods are all based on Gaussian assumption so can not accurately describe the non-Gaussian feature of road excitation. In this paper, a parameters recognition method of the non-Gaussian feature of road excitation and a method of reconstructing non-Gaussian time-domain excitation based on recognition results are proposed based on the theory of symmetric stable distribution. The methods are applied to the reconstruction of collected spectra of test ground track for a construction vehicle. The results show that the reconstructed spectra has similar RMS values as that of collected spectra, and can accurately reflect the non-Gaussian features of original collected excitation amplitude. [ABSTRACT FROM AUTHOR]

Abstract: Phenological changes are closely related to the carbon cycle of terrestrial ecosystems, and satellite data have been widely used in large scale phenological research. Numerous methods have been developed to reconstruct distinct satellite derived vegetation signals from continuous vegetation index time series and to track the points corresponding to important phenological events. In this study, we perform a multiple-method investigation of the spring vegetation growth onset phenology in temperate China north of 30°N with NDVI (normalized difference vegetation index) data produced from SPOT satellites. The results indicated that the spring onset dates estimated from five different methods show similar spatial pattern along latitudinal or altitudinal gradients, but with significant variances in the dates. In most areas (76% of pixels), the standard deviation (SD) of the estimated spring onset dates from different methods is within one month, while in a few places (2% of pixels), mostly agricultural cropland, the SD is more than 60 days. Comparing the satellite derived green-up onset dates against the gross primary productivity (GPP) time series curves acquired from six eddy covariance towers further highlights the strengths and limits of different methods in estimating phenological events. In a vast region with diverse vegetation types and physical environment, it is critical to choose the “right” method for the “right” place. Generally climate factors such as temperature and precipitation play an important role in controlling the start of vegetation growth in temperate China. Yet this climate-phenology relationship varies largely across different regions and vegetation types. [Copyright &y& Elsevier]

Abstract: This paper describes a response acquisition system composed of some spindle accelerometers and a time synchronized on-board GPS receiver developed in order to collect the dynamic response of vehicle riding on an unpaved road. A method of time-space conversion for calculating the response spectrum is proposed to eliminate the adverse effect of time-varying speed, based on the transform from the equitime sampled spindle acceleration responses to equidistance sampling. By using two groups of independent distance histories acquired from GPS, a method called long-range error correction is proposed to improve the accuracy of the vehicle's distance information, which is critical for the time-space conversion. The accuracy and limitations of the system have been analyzed, and its validity has been verified by implementing the system on a wheel loader for road response spectrum measuring. This paper offers a practical approach to obtaining unpaved road response spectra for durability road simulation. [ABSTRACT FROM AUTHOR]

2D Raman generated classical and quantum Talbot imaging is proposed in a three‐level gain assisted system. First, a 2D Raman induced grating (RIG) will be constructed by modulating transmission function in the weak probe channel using a strong control standing wave field. Furthermore, RIG will diffract a probe field, by shining a probing light beam on an optically generated lattice within a rubidium vapor cell. This study uses gain assisted Raman medium [Nature406, 277 (2000)] to examine classical and quantum Talbot imaging. In the case of Raman‐induced classical imaging, the diffraction pattern repeats itself at planes with integer multiple Talbot lengths. Additionally, by taking into account entangled photon pairs, the scenario of Raman‐induced quantum imaging is investigated. This study also looks at the RIG's amplitude and phase information with adjustable image size variation. As a result of the gain feature and zero absorption, this system is anticipated to be more suitable from the perspective of application. This analysis may pave the way for further research into the Talbot effect's nonlinear and quantum dynamical properties. Also, it provide a non‐destructive, lensless method for imaging very cold atoms or molecules. [ABSTRACT FROM AUTHOR]

Abstract: AimsVegetation dynamics are simultaneously regulated by climate change and anthropogenic activities. Since the 1980s, climate has been warming on the Tibetan Plateau (TP) at a rate higher than North hemisphere average. Anthropogenic activities, including grazing, farming, and urbanization, are also influencing the alpine ecosystem on the TP. Especially, an ensemble of large engineering projects, such as power transported from west to east by State Grid, have been in operation on the TP. While studies disentangling effects of climate and anthropogenic activities interference are still lacking for the forest ecosystems on the TP. The overarching objectives of this study were to separate effects of natural climates and human interferences on forest ecosystem dynamics on the TP. Methods We compared vegetation activities of two typical natural reserves (Gongbu natural reserve, GNR, and Yarlung zangbo river grand canyon natural reserve, YNR) and their surroundings in southeastern Tibet (outside of the natural reserves, ONR) using long-term satellite NDVI dataset. Linear regression and partial correlation analyses were constructed for the relationship between vegetation activity and climates to evaluate the distinct climate effects on the two natural reserves.Important FindingsThe two natural reserves were established at different time, which were related to anthropogenic activities impact durations. The results showed that the annual mean NDVI fluctuated between 0.5 and 0.6 in the relatively longer reserved YNR, which was remarkably higher than those in other regions (with NDVI lower than 0.45). The vegetation vigor in the YNR showed neither a significant temporal trend nor significant relationship with climate. Nevertheless, vegetation vigor exhibited a significant increasing trend during the last three decades (0.012/decade) at the GNR. The inter-decadal analysis turned out positive relationships between vegetation vigor and annual temperature since late 1990s until early 2000s when the GNR was officially established. This study underlined the importance of considering human interference duration when assessing the relationships between vegetation dynamics and climates. [ABSTRACT FROM AUTHOR]

Changes in the start and end of vegetation growing season (SOS and EOS) are insightful for assessing ecosystem response to climate change because of the high sensitivity of phenology to the climate and their extensive influences on terrestrial ecological processes. From 1982 to 2011, dramatic climate warming resulted in substantial increases in SOS on the Tibetan Plateau (TP). However, it is unclear how EOS changes during this period. We employed multiple remote sensing methods to estimate EOS and SOS from satellite NDVI, and investigated the relationship between EOS and its drivers. We also conducted an analysis on the contribution of EOS and SOS to the change of growing season length (GSL). It showed that EOS was primarily driven by preseason temperature, and partly by precipitation and solar insolation. In the southwestern TP, EOS was significantly and positively related with SOS, suggesting a potentially indirect effect of winter meteorological conditions on the following autumn phenology through the regulation of spring phenology. During this period, on average, SOS remarkably advanced by 0.14 day/year (P = 0.086), whereas EOS showed only slight and insignificant delay (0.08day/year, P = 0.140), implying the regionally averaged extension of GSL was mainly caused by an earlier spring. For spatial pattern, SOS mainly advanced (73%) and EOS primarily delayed (73%). As a result of the variation, 79% of the pixels showed extended GSL, where 67% of them were primarily caused by SOS advance, and the other 33% were mainly caused by EOS delay. Interestingly, areas where the spring was the key factor for GSL extension were mainly distributed in relatively dry western part of TP, and contrarily, autumn contributed more to the GSL were located in the wetter northeastern part. This phenomenon suggests the shifts of GSL are dependent on environmental conditions by the performance SOS and EOS. [ABSTRACT FROM AUTHOR]

[Display omitted] • Precipitation threshold dividing forest pattern increased with increasing temperature. • Climatic effects on forest LAI changed with increasing temperature and precipitation. • Changing MAT and MAP thresholds divided forests with different climatic effects. How climatic effects on forest greenness vary between different temperature and precipitation gradients in climate–sensitive and ecologically fragile areas, such as the Yellow River Basin (YRB) in China, is not well understood. Here we used meteorological data and remotely sensed leaf area index (LAI) data to investigate climatic effects on forest LAI changes along temperature–precipitation gradients in the YRB from 2001 to 2020. We found that changing precipitation thresholds divided forests into higher and lower LAI areas. The precipitation thresholds increased from 400 mm mean annual precipitation (MAP) in areas with a mean annual temperature (MAT) below 4 °C to 500 mm MAP in areas with a MAT above 4 °C. Forest LAI increased significantly from 2001 to 2020. The MAT and MAP thresholds changed when dividing forests into different areas with different LAI values and climatic effects. Forests greening was mainly driven by temperature in areas with LAI values between 3 and 6 m2 m−2 but was mainly driven by precipitation in areas with LAI values less than 3 m2 m−2. The threshold of MAP isopleth increased from 500 mm to 700 mm and then decreased to 500 mm, while the MAT increased from less than 0 °C to 5 °C and then increased to 12 °C. These divergent climatic effects were caused by the combined effects of water resource limitations and increasing evapotranspiration. Identifying MAT and MAP thresholds is helpful for decision–maker and managers to optimize forest restoration more accurately in future ecological protection projects facing the challenge of limited water resources in the YRB. [ABSTRACT FROM AUTHOR]

Warming drives poleward expansion of forests over high latitudes. However, it remains unresolved whether the poleward forest lines can track the warming rate at continental scales. To answer this question, we compared latitudinal forest line shifts detected by remote sensing under the early 21st century's warming (i.e., from 2000 to 2019) with shifts of temperature isolines derived from a time-invariant temperature-forest line relationship. The results show that the northward forest line shift in North America (NA) can generally keep pace with changes in temperature isolines; while in Eurasia (EA) it greatly trails that of temperature changes. Therefore, the northward shift of the forest line tracking temperature warming over NA is much faster than that over EA. The slower warming rate over NA allows slow temperature acclimation. In contrast, the warming rate is much faster in EA, which makes other environmental factors (e.g., winter temperature, water stress, and active layer thickness, biotic factors, and land use and land cover change) increasingly important in limiting the northward shift of forest lines. • Warming has led to northward shifts of forest lines in northern high latitudes. • The northward shift of forest lines is much faster in North America than in Eurasia. • Differences in warming acclimation can help explain the divergent northward shifts. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) is closely associated with urban and rural development. To study the spatiotemporal evolution of the LST, we used daily night light and LST data as well as the gravity model, coupling coordination model, standard deviation ellipse, and other methods. Under the analysis–coordination–gravity framework, we studied the spatiotemporal and gravitational evolution of the nighttime LST in the Henan Province in 2013, 2016, 2019, and 2022. Our research revealed significant differences in the high-brightness values of nighttime lighting between different years and seasons. The maximum offset distance occurred in the winters of 2013–2016 at 20,933.28 m, whereas the minimum offset distance was observed in the autumns of 2019–2022 at 1196.03 m. In addition, the spatiotemporal gravity of the LST exhibits a certain evolution pattern. Although differences in the direction of evolution and the distribution of high gravity density were found, a homogenization trend was observed for the distribution of gravity in the spring of 2016, autumn of 2019, and summer of 2022. LST shows different characteristics over changing space and seasons, and its gravity shows the characteristics of spatial aggregation. The results provide new ideas for LST studies and are of significance for the restoration of ecosystems. [ABSTRACT FROM AUTHOR]

Climate warming is predicted to considerably affect variations in soil organic carbon (SOC), especially in alpine ecosystems. Microbial necromass carbon (MNC) is an important contributor to stable soil organic carbon pools. However, accumulation and persistence of soil MNC across a gradient of warming are still poorly understood. An 8‐year field experiment with four levels of warming was conducted in a Tibetan meadow. We found that low‐level (+0–1.5°C) warming mostly enhanced bacterial necromass carbon (BNC), fungal necromass carbon (FNC), and total MNC compared with control treatment across soil layers, while no significant effect was caused between high‐level (+1.5–2.5°C) treatments and control treatments. The contributions of both MNC and BNC to soil organic carbon were not significantly affected by warming treatments across depths. Structural equation modeling analysis demonstrated that the effect of plant root traits on MNC persistence strengthened with warming intensity, while the influence of microbial community characteristics waned along strengthened warming. Overall, our study provides novel evidence that the major determinants of MNC production and stabilization may vary with warming magnitude in alpine meadows. This finding is critical for updating our knowledge on soil carbon storage in response to climate warming. [ABSTRACT FROM AUTHOR]

Vegetation activity on the Tibetan Plateau grassland has been substantially enhanced as a result of climate change, as revealed by satellite observations of vegetation greenness (i.e., the normalized difference vegetation index, NDVI). However, little is known about the temporal variations in the relationships between NDVI and temperature and precipitation, and understanding this is essential for predicting how future climate change would affect vegetation activity. Using NDVI data and meteorological records from 1982 to 2011, we found that the inter-annual partial correlation coefficient between growing season (May-September) NDVI and temperature (R) in a 15-year moving window for alpine meadow showed little change, likely caused by the increasing R in spring (May-June) and autumn (September) and decreasing R in summer (July-August). Growing season R for alpine steppe increased slightly, mainly due to increasing R in spring and autumn. The partial correlation coefficient between growing season NDVI and precipitation (R) for alpine meadow increased slightly, mainly in spring and summer, and R for alpine steppe increased, mainly in spring. Moreover, R for the growing season was significantly higher in those 15-year windows with more precipitation for alpine steppe. R for the growing season was significantly higher in those 15-year windows with higher temperature, and this tendency was stronger for alpine meadow than for alpine steppe. These results indicate that the impact of warming on vegetation activity of Tibetan Plateau grassland is more positive (or less negative) during periods with more precipitation and that the impact of increasing precipitation is more positive (or less negative) during periods with higher temperature. Such positive effects of the interactions between temperature and precipitation indicate that the projected warmer and wetter future climate will enhance vegetation activity of Tibetan Plateau grassland. [ABSTRACT FROM AUTHOR]

Reasonable allocation of urban resources can effectively control changes in ecological quality. This study used Sentinel-2 images, taking urban functional areas as the dividing scale, and combined spatial analysis, statistics, and other relevant methods to explore the factors influencing remote sensing ecological quality in Puxi, Shanghai, China. Landsat-8 and high-resolution Sentinel-2 data fusion achieved more refined remote sensing ecological index (RSEI) distribution data, which is of great significance for ecological quality exploration in small areas; the degree of influence of the selected research factors on the RSEI was spectral index > building > social perception > terrain. The R-value of the soil-adjusted vegetation index (SAVI) was 0.970, and it exerted the strongest influence. The R-value of the average building height was 0.103, indicating that it had the weakest influence. The interactions among the selected factors were mainly two-factor and nonlinear enhancements. Most factor combinations exhibited two-factor enhancement. There were six groups of factor combinations for nonlinear enhancement, of which five were related to the average building height. The results of the present study provide a reference for multi-path ecological quality control in small-area regions. [ABSTRACT FROM AUTHOR]

• Cold environment suppressed the accumulation of microbial-derived C in the soil. • Warming increased microbial residues in the soil, but N addition decreased it. • Warming weakened the N-driven negative effect on soil C stability. Microbial-derived soil organic carbon has attracted increased attention as an important source of soil organic matter that may affect soil carbon persistence. Ecosystems at high elevation and latitude contain massive amounts of soil organic carbon that is potentially vulnerable to rapid climate change. However, little is known about the mechanisms that govern the production and accumulation of carbon derived from microbes in the context of global changes for these regions. Here, we investigate soil biomarkers from membrane lipids and microbial residues in an experiment with six-year warming and nitrogen (N) addition treatments in an alpine meadow of the Tibetan Plateau. The results showed low accumulation of amino sugars in soil (167.51 to 297.36 μg·g−1) for this alpine meadow. After the six-year manipulative experiment, warming promoted accumulation of microbial-derived carbon in soil with both increased bacterial (increased by 53.56%) and fungal carbon (increased by 25.60%). Nitrogen addition inhibited microbial-derived carbon accumulation (decreased by 25.37%) and significantly decreased the fungal carbon content relative to bacterial carbon content. Climate warming tended to weaken this N-driven negative effect. As microbial residues relate closely with soil organic matter stability, these results highlight the potential of global change factors (warming and N addition) to alter the structure and persistence of soil organic matter, with important implications in refining carbon cycle-climate models. [ABSTRACT FROM AUTHOR]

Purpose: Three-dimensional (3D) printing provides more possibilities for composite manufacturing. Composites can no longer just be layered or disorderly mixed as before. This paper aims to introduce a new algorithm for dual-material 3D printing design. Design/methodology/approach: A novel topology design method: solid isotropic material with penalization (SIMP) for hybrid lattice structure is introduced in this paper. This algorithm extends the traditional SIMP topology optimization, transforming the original 0–1 optimization into A–B optimization. It can be used to optimize the spatial distribution of bi-material composite structures. Findings: A novel hybrid structure with high damping and strength efficiency is studied as an example in this work. By using the topology method, a hybrid Kagome structure is designed. The 3D Kagome truss with face sheet was manufactured by selective laser melting technology, and the thermosetting polyurethane was chosen as filling material. The introduced SIMP method for hybrid lattice structures can be considered an effective way to improve lattice structures' stiffness and vibration characteristics. Originality/value: The fabricated hybrid lattice has good stiffness and damping characteristics and can be applied to aerospace components. [ABSTRACT FROM AUTHOR]

The ongoing changes in vegetation spring phenology in temperate/cold regions are widely attributed to temperature. However, in arid/semiarid ecosystems, the correlation between spring temperature and phenology is much less clear. We test the hypothesis that precipitation plays an important role in the temperature dependency of phenology in arid/semiarid regions. We therefore investigated the influence of preseason precipitation on satellite-derived estimates of starting date of vegetation growing season ( SOS) across the Tibetan Plateau ( TP). We observed two clear patterns linking precipitation to SOS. First, SOS is more sensitive to interannual variations in preseason precipitation in more arid than in wetter areas. Spatially, an increase in long-term averaged preseason precipitation of 10 mm corresponds to a decrease in the precipitation sensitivity of SOS by about 0.01 day mm−1. Second, SOS is more sensitive to variations in preseason temperature in wetter than in dryer areas of the plateau. A spatial increase in precipitation of 10 mm corresponds to an increase in temperature sensitivity of SOS of 0.25 day °C−1 (0.25 day SOS advance per 1 °C temperature increase). Those two patterns indicate both direct and indirect impacts of precipitation on SOS on TP. This study suggests a balance between maximizing benefit from the limiting climatic resource and minimizing the risk imposed by other factors. In wetter areas, the lower risk of drought allows greater temperature sensitivity of SOS to maximize the thermal benefit, which is further supported by the weaker interannual partial correlation between growing degree days and preseason precipitation. In more arid areas, maximizing the benefit of water requires greater sensitivity of SOS to precipitation, with reduced sensitivity to temperature. This study highlights the impacts of precipitation on SOS in a large cold and arid/semiarid region and suggests that influences of water should be included in SOS module of terrestrial ecosystem models for drylands. [ABSTRACT FROM AUTHOR]

Global greening and its eco-environmental outcomes are getting mounting international focus. The important contribution of China to the global greening is highly appreciated. However, the basic driving forces are still elusive. The Loess Plateau (LP) and Three-River Source Region (TRSR) were chased as study areas in Northern China. The prior one represents the region experiencing intensive human interventions from ecological engineering projects, while the latter is a typical region that is experiencing faster climate change. Hypothesized to be driven by a disproportionate rate of human activities and climates, also being regions of typical large-scale ecological engineering projects, the study goal is to identify the actual driving forces on vegetation dynamics in these two regions. Trend analysis, correlation analysis, and residual trend-based method (RESTREND) were utilized to understand the relationships between climate variability, human activities, and vegetation dynamics. The spatiotemporal variations of vegetation from 1982 to 2019 were evaluated and the respective impacts of climatic and anthropogenic factors on vegetation dynamics were disentangled. Indicating apparent vegetation restoration in LP and TRSR, the results depict that annual LAI has remarkably increased during the 38 years. Temperature and precipitation promoted vegetation growth, whereas the solar radiation and vapor pressure deficit hampered it. After implementing the ecological engineering projects, the primary climatic factor changed from temperature to precipitation. Meanwhile, human activities act as the major driving factor in vegetation greening in the entire study area, with a contribution rate exceeding 70%. This information highlights that ecological engineering can significantly reduce the risks of ecosystem degradation and effectively restore vegetation, especially in ecologically sensitive and vulnerable areas. [ABSTRACT FROM AUTHOR]

Aims: Vegetation in high-altitude regions is hypothesized to be more responsive to increasing atmospheric CO2 concentrations due to low CO2 partial pressure. However, the underlying mechanisms driving this response at an ecosystem scale are poorly understood. We aimed to explore the plant carbon (C) and nitrogen (N) relationships and biomass allocation in response to elevated CO2 and N addition in a Tibetan meadow. Methods: A 5-year manipulation experiment was conducted in an alpine meadow (4585 m above sea level) to explore the responses of plant carbon (C), nitrogen (N), and biomass dynamics, as well as their allocation schemes, to elevated CO2 (from 380 ppm to 480 ppm) and N fertilization. Results: Elevated CO2 alone significantly enhanced aboveground plant biomass by 98%, exhibiting a stronger CO2 fertilization effect than the global average level (20%) for grasslands. Elevated CO2 favored N accumulation in aboveground parts despite the declined concentration. Nitrogen fertilization alleviated the N constraints on CO2 fertilization effects, which strengthened C sequestration capacity for the aboveground plant tissues. Moreover, our results indicate a decoupling between C and N cycles in alpine ecosystems under elevated CO2, especially in the N-enrichment environments. Conclusions: Overall, this study shows a high sensitivity of aboveground plant biomass and decoupled C-N relationships under elevated CO2 and N fertilization for high-elevation alpine ecosystems, highlighting the need to incorporate altitude effects into Earth System Models in predicting C cycle feedbacks to climate changes. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Qinghai–Tibetan Plateau (QTP) experienced intensive warming over 2000–2011. [•] Regionally, spring phenology on the QTP showed no significant trend (P >0.05). [•] The spring warming was more intensive in the southwestern QTP than the other areas. [•] Delayed spring phenology in the SW QTP may be caused by declined precipitation. [•] Precipitation may be an important control of spring vegetation phenology for the QTP. [Copyright &y& Elsevier]

Grassland biodiversity is vital for the provision of multiple ecosystem functions, termed ecosystem multifunctionality. As an effective practice of grassland management, grazing exclusion is widely used to restore the ecosystem multifunctionality of degraded grasslands, but it might not be always beneficial for conserving grassland biodiversity. Moreover, when grazing is excluded, it remains unknown whether grassland biodiversity promotes multifunctionality. Here, we conducted a field experiment of grazing exclusion along a gradient of climatic aridity across four major grassland types in the arid grasslands of northern China. We determined the effects of grazing exclusion on biodiversity and multifunctionality, and further investigated how grazing exclusion could modify biodiversity-multifunctionality relationships. We found that grazing exclusion increased soil fungal diversity, but had negligible effects on plant species richness and soil bacterial diversity. The effects of grazing exclusion on multifunctionality varied among grassland types: it promoted multifunctionality only in less arid grasslands. Importantly, multifunctionality was positively associated with plant species richness under grazing, but this positive association disappeared under grazing exclusion. In addition, we showed that climatic aridity affected multifunctionality indirectly through its negative effect on plant species richness under grazing, whereas such effect disappeared under grazing exclusion. Furthermore, aridity weakly reduced multifunctionality under grazing, and its negative effect was strengthened under grazing exclusion. Our results suggest that grazing exclusion restrains the capacity of plant biodiversity to sustain multiple ecosystem functions, and moreover, aggravates the negative influences of climatic dryness on ecosystem multifunctionality. Our findings illustrate the value of grazing for maintaining biodiversity-multifunctionality relationships and for mitigating the impacts of climate change in arid grasslands. • Grazing exclusion increases soil fungal diversity in the arid grasslands of China. • Grazing exclusion promotes multifunctionality only in less arid grasslands. • Grazing exclusion jeopardizes plant biodiversity effect on multifunctionality. • Grazing exclusion enhances the negative effect of aridity on multifunctionality. [ABSTRACT FROM AUTHOR]

Aim: Ecosystem carbon use efficiency (CUEe) is a core parameter of ecosystem process models, but its relationships with climate are still uncertain, especially for ecosystems with harsh environments. Large inconsistencies in climate impacts on the CUEe have been reported among various spatial scales. The goal of this study was to examine whether warming promotes or restricts the CUEe and whether the CUEe responds to a warming gradient in a linear or nonlinear manner. Location: Tibetan Plateau. Time period: 2000–2018. Major taxa studied: Alpine grassland ecosystem. Methods: We integrated multiple‐source data of carbon fluxes and CUEe, including warming experiments at a site scale, eddy covariance observations at a landscape scale and synthesized warming experiments and ecosystem process models at a regional scale. Next, we deployed a statistical model to examine the warming impacts on the CUEe across scales; the effects of biotic and abiotic factors on the CUEe and its components were summarized based on the results of standardized major axis tests and routines, structural equation modelling and nonlinear models. Results: This study reported a suppressive warming impact on the CUEe, which followed a nonlinear curve with severe inhibition in the high‐level warming treatment. With a warming threshold of 1.5–2.0°C, CUEe response patterns transitioned from no change to a significant decrease. The restriction effects can be ascribed to the joint adverse and asymmetric effects of warming on CUEe components under multiple‐level warming. Warming‐modified relationships among CUEe components and the nonlinear effects of biotic and abiotic factors led to the nonlinear responses of CUEe to warming. Main conclusions: This study revealed suppressive and nonlinear effects of warming on the CUEe, including especially dramatic CUEe decreases with high‐level warming. These findings are critical for optimizing model parameters and improving predictions of the carbon sequestration capacity of alpine grasslands. [ABSTRACT FROM AUTHOR]

• An eco-hydraulic model was proposed for reservoir regulation. • Abundance and distribution of two fish species in the Williston reservoir were depicted. • Fish habitat as well as fish entrainment risk under seasonal operation were modeled. • Reservoir regulations have significant effect on entrainment risk of kokanee. • Eco-hydraulic modeling optimizes reservoir operation for mitigating entrainment risk. Hydroelectric development and fish entrainment pose significant threats to fish populations, thereby exerting a profound impact on ecosystem functioning within human-affected river systems. This study addresses the potential loss of numerous fish species from the reservoir due to hydraulic diversions. An approach to assess both physical habitat and fish entrainment risk in the Williston Reservoirs was introduced, with a focus on two fish species: bull trout (Salvelinus confluentus) and kokanee salmon (Oncorhynchus nerka). The modeled results illuminate a seasonal fluctuation in forebay entrainment risk resulting from the operated intakes. The entrainment risk for kokanee in summer is highest, followed by fall and winter, while spring has the least entrainment risk. Modeled results also suggest that kokanee entrainment risks increase with flow rate of the operated intakes. Due to the fish entrainment risk, kokanee density and population decrease during the reservoir regulation, potentially leading to a reduction in the overall kokanee population over time. Conversely, the entrainment risk for bull trout remains limited, and its density and population appear to be unaffected by reservoir regulation and the subsequent fish entrainment risk. These insights hold relevance for optimizing operations in different seasons, and provide valuable input for informed decision-making aimed at mitigating the risks associated with fish entrainment. [ABSTRACT FROM AUTHOR]

• Droughts enhanced the control effects of biotic factors on carbon and water fluxes. • Droughts induced changes in the driving paths of biotic and abiotic factors on RUE. • RUE responded differently to droughts in different periods in the growing season. • Droughts in the mid-growing season reduced the RUE. Drought is a threat universally faced by global terrestrial ecosystems under global climate change. The habitat of alpine ecosystems is harsh, and they necessitate to use the limited resources efficiently to survive. However, drought occurred frequently during the short growing season, which greatly affected their resource use efficiency (RUE). In this study, based on long-term flux and microclimate observations in a typical alpine meadow ecosystem in northern Tibet, the effects of drought on RUE, including water use efficiency (WUE), light use efficiency (LUE), and carbon use efficiency (CUE), were studied. The results indicate that droughts could change the driving paths of abiotic and biotic factors on carbon and water fluxes and hence affect RUE. When vegetation exhibits robust physiological activity, droughts could enhance the control effects of biotic factors. The droughts that occurred at different periods of the growing season showed divergent effects on RUE. In the early-growing season, the strong photosynthetic capacity of the nascent leaves facilitated enhancements in WUE and LUE in response to drought conditions. However, the CUE did not increase significantly due to the heightened consumption of organic matter by respiration. The mid-growing season droughts led to a sharp decrease in gross primary productivity (GPP), consequently leading to a decline in WUE, LUE and CUE. During the late-growing season, droughts together with the decomposition of chlorophyll reduced the photosynthetic capacity and led to a significant decrease in LUE. The diminished physiological activity of the senescent leaves led to insensitive responses of WUE and CUE to droughts. These findings indicate that RUE might primarily be regulated by factors affecting GPP rather than others. This study would be beneficial for assessing the responses and adaptation characteristics of alpine meadow ecosystems to future climate change and could help accurately predict their possible evolution trends. [ABSTRACT FROM AUTHOR]

• The first study to use high-resolution images to survey pika hole size and area. • The first study to explore pika hole distribution pattern at a landscape scale. • Effects of pika hole on plant growth in the surrounding varies with pika hole size. • Vegetation coverage affects pika hole density in alpine meadow. The pika (Ochotona curzoniae) hole is an important landscape feature in the Tibetan Plateau (TP) grasslands, and it indicates grassland degradation levels due to the destruction caused by pika burrowing activities on grasslands. However, no studies have ever explored landscape patterns of pika holes and their effects on adjacent vegetation coverage. Taking meadow grasslands in Northern Tibet as an example, this study gathered unmanned aerial vehicle (UAV) images and explored landscape patterns of pika holes and their effects on grass coverage in the surroundings. The performances of two classification methods, including the decision tree classification based on Fully Constrained Least Squares (FDC) and the object-oriented classification (OBC) were compared in recognizing sizes and shapes of pika holes. The results showed that: (1) The object-oriented classification exhibits higher classification accuracy in identifying pika holes. (2) The average size of pika holes in the study area is 0.01 m2 and they exhibit clustered distribution patterns. The average distance between any two nearest pika hole patches is 0.79 m. (3) It presents a significant quadratic relationship between the number of pika holes and grass coverage. (4) The average effective distance of pika holes on the surrounding grass coverage is 20 cm. The findings of this study can provide guidelines for pika control and improve grassland management on the TP. [ABSTRACT FROM AUTHOR]

Objective: To elucidate the sleep quality characteristics and factors related to either good or poor sleep quality in acromegaly patients before surgery and to explore sleep quality changes after transsphenoidal surgery and the factors related to these changes.Methods: We prospectively enrolled 39 acromegaly patients and 78 patients with nonfunctioning pituitary adenomas. Scales for anxiety, depression, disease stigma and nasal condition were evaluated. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was administered before surgery as well as one month and three months after surgery.Results: A higher percentage of acromegaly patients had poor sleep quality compared to controls (35.9% vs. 5.1%, p < 0.001). In addition, acromegaly patients experienced worse subjective sleep quality, extended sleep latency, increased sleep disturbance and decreased daytime functioning. Higher scores for anxiety, disease stigma and sinonasal outcomes were correlated with worse sleep quality in acromegaly patients. At one month after transsphenoidal surgery, we found worse subjective sleep quality, extended sleep latency, shortened sleep duration, impaired sleep efficiency and increased sleep disturbance in acromegaly patients. At three months postoperatively, most impaired PSQI domains in acromegaly patients recovered to preoperative levels. The use of soluble gauze was related to decreased sleep quality at one month after surgery and severe anxiety and depression were related to improved sleep quality at three months after surgery.Conclusions: Sleep quality was reduced in acromegaly patients. Moreover, sleep quality initially worsened after surgery but later recovered. Emotional problems and the use of soluble gauze were related factors.Clinical Trial Registration: None. [ABSTRACT FROM AUTHOR]

• Discrepancies exist with different data in phenology extractions. • High temporal resolution data has higher accuracies in capturing SOS. • Double logistic method can minimize the extraction difference. The vegetation phenology is a commonly used indicator signaling vegetation responses to global changes. Monitoring vegetation phenology at a regional and global scale needs to rely to remote sensing data, for which multiple sources of datasets and extraction methods have been developed. To be efficient, remote sensing data with coarse temporal resolution is conventionally preferred in exploring vegetation phenology patterns at the continental or global scale. As fine temporal resolution data is increasingly available, effects of their temporal resolution on our analysis are still elusive. In this study, we applied several commonly utilized vegetation phenology extraction methods on two different temporal resolution MODIS NDVI data and compared their performances on the Tibetan Plateau (TP). The results showed there were certain discrepancies in the magnitude, trends and spatial patterns of extracted phenological parameters between the two datasets and among the different extraction methods. Generally, the phenological parameters derived from fine temporal resolution NDVI (MOD09A1) displayed later start of growing season (SOS), earlier end of growing season (EOS), shorter length of growing season (LOS), and were more accurate in capturing vegetation SOS compared with the coarse temporal resolution NDVI data (MOD13A2). The double logistic method can minimize the differences of extracted SOS or EOS between the two temporal resolution datasets. The findings of this study would improve accuracies of applying remote sensing data on monitoring vegetation dynamics and advance our understanding on vegetation responses to climate changes. [ABSTRACT FROM AUTHOR]

Effects of climate warming and changing precipitation on ecosystem carbon fluxes have been intensively studied. However, how they co‐regulate carbon fluxes is still elusive for some understudied ecosystems. To fill the gap, we examined net ecosystem productivity (NEP), gross ecosystem productivity (GEP,) and ecosystem respiration (ER) responses to multilevel of temperature increments (control, warming 1, warming 2, warming 3, warming 4) in three contrasting hydrological growing seasons in a typical semiarid alpine meadow. We found that carbon fluxes responded to precipitation variations more strongly in low‐level warming treatments than in high‐level ones. The distinct responses were attributable to different soil water conditions and community composition under low‐level and high‐level warming during the three growing seasons. In addition, carbon fluxes were much more sensitive to decreased than to increased precipitation in low‐level warming treatments, but not in high‐level ones. At a regional scale, this negative asymmetry was further corroborated. This study reveals that future precipitation changes, particularly decreased precipitation would induce significant change in carbon fluxes, and the effect magnitude is regulated by climate warming size. [ABSTRACT FROM AUTHOR]

• The soil water content and temperature determined the maximum photosynthesis. • Sufficient soil water elevated the optimal temperature and maximum photosynthesis. • The optimal environmental configuration for the alpine meadow was detected. • If soil water is high, higher temperature and VPD are beneficial for carbon uptake. The changes in the carbon sink function of sensitive and fragile alpine ecosystems under climate change are widely concerned. Radiation, temperature, and water resources play important roles in regulating carbon assimilation. Therefore, it is important to detect the optimal configuration of environmental factors for the photosynthesis of alpine meadow ecosystems. In this study, based on 10-year flux and corresponding environmental observations in a typical alpine meadow ecosystem, the optimal environmental configuration that could realistically occur in the natural world for photosynthesis was detected. The results indicated that the temperature and water conditions were the primary limiting factors, as radiation resources are abundant on the Tibetan Plateau. The optimal temperature for photosynthesis (TA opt) was determined to be 11.92 ℃ based on the entire observation dataset, with a maximum photosynthetic capacity (GPP max) of 0.20 mg CO 2 m−2 s−1. However, the TA opt and the corresponding GPP max could be elevated when the soil water content (SWC) was abundant. When SWC exceeded 0.26 m3 m−3, TA opt increased to 13.41 ℃, and the corresponding GPP max reached as high as 0.30 mg CO 2 m−2 s−1, which is the maximum the ecosystem could reach. Thus, the optimal environmental configuration for photosynthesis that could realistically occur in the natural world in this alpine meadow was air temperature (TA)=13.41 ℃, SWC=0.28 m3 m−3, vapor pressure deficit (VPD)=0.61 kPa, net radiation (RN)=411.53 J m−2 s−1. According to this study, it could be inferred that within a reasonable range, higher temperatures and VPD would benefit photosynthesis in this alpine meadow as long as the soil water supply is sufficient. The climate on the Tibetan Plateau is arid with high VPD and is experiencing warming due to climate change. Consequently, alpine ecosystems situated in relatively humid regions with sufficient soil water resources may exhibit greater potential for carbon sequestration than previously estimated. [ABSTRACT FROM AUTHOR]

• The ecohydraulic modeling framework is a valuable tool for assessing fish ecology in dammed rivers. • Cascade dam construction could fragment spawning site habitats and reduce fish population abundance in the tailwater zone of the main stream. • Spawning site habitats would improve, leading to an increase in fish population abundance in the backwater zone of tributaries. • The effects of cascade dam construction on endemic fish habitat and population status depend on spawning site location, fish species, and life stages. Cascade dam constructions will alter the habitat of spawning sites and affect fish population in the Lancang River basin. This paper examines the impacts of cascade dam construction on four spawning sites, focusing on two co-distributed and endemic fish species: Schizothorax prenanti and Schizothorax davidi. An ecohydraulic modeling framework that combined hydro-morphodynamic, habitat, and population models was used to investigate changes in habitat quality and fish population under two scenarios: no-dam and with-dam. Fish habitat quality was evaluated using the habitat suitability index, and population fluctuations were assessed by the abundance and density of fish populations at all life stages. The simulation results indicated that cascade dam construction would fragment the spawning site habitat in the tailwater zone of the main stream and result in a decrease in fish population abundance and density. Conversely, spawning site habitats in backwater zone of tributaries would improve, and fish population abundance and density would increase. Additionally, the simulation results showed that the magnitude of fish population variations varied by species and life stages. These results highlight the different responses of spawning site location, fish species, and life stages to dam construction, which can help identify areas of the habitat with higher potential for finer-scale endemic fish conservation and recovery efforts. This study provides a comprehensive framework tool for fish ecological evaluation in dammed rivers, which has the potential to assist decision-makers involved in river ecosystem ecological conservation. [Display omitted] [ABSTRACT FROM AUTHOR]

The alpine ecosystems on the Qinghai-Tibetan Plateau are quite sensitive to climate change. The increasing temperature and changing precipitation patterns greatly affect the gross primary productivity (GPP) and disturb the carbon balances of these alpine ecosystems. To clarify the impacts of future climate change across the Qinghai-Tibetan Plateau, it is important to address the scientific issue "Which factor would dominate interannual variability (IAV) in GPP and through which path does it work?" To clarify this issue, two key processes, growing season length (GSL) and maximum photosynthetic capacity (GPP max), were introduced to reveal the underlying mechanisms, and which of the environmental factors dominated their variations were studied specifically based on the flux and corresponding environmental observation data obtained in different types of alpine ecosystems across the Qinghai-Tibetan Plateau in this study. The results indicated that across the temperature- and water-limited alpine ecosystems, the temperature controlled the GSL, but the water conditions dominated the variations in GPP max. The soil water content (SWC) dominated GPP max , which could explain 89% of the variation in GPP max. The GSL alone was incapable of explaining IAV in GPP. Conversely, GPP max is robust in explaining IAV in GPP, which could explain 94% of the annual GPP. Therefore, climate change would probably drive IAV in GPP through the path of "SWC → GPP max → annual GPP" on the Qinghai-Tibetan Plateau. In addition, GPP max together with GSL (GSL × GPP max) could explain 99% of IAV in GPP, as they indicated the length of the carbon uptake time and the capacity of carbon sequestration, respectively. This study provides a new perspective on the predominant causes of IAV in GPP in alpine ecosystems, indicating that the changing precipitation patterns under future climate change will play a dominant role in affecting the carbon sink function of the Qinghai-Tibetan Plateau. [Display omitted] • Temperature dominated the growing season length (GSL) in alpine ecosystems. • Soil water content (SWC) dominated the maximum photosynthetic capacity (GPP max). • GPP max rather than GSL dominated the annual GPP. • GSL and GPP max coexplained 99% of the interannual variability in annual GPP. • Climate change drove GPP through two key underlying processes: GSL and GPP max. [ABSTRACT FROM AUTHOR]

As the recent global warming hiatus and the warming on high elevations are attracting worldwide attention, this study examined the robustness of the warming slowdown over the Tibetan plateau (TP) and its related driving forces. By integrating multiple-source data from 1982 to 2015 and using trend analysis, we found that the mean temperature (Tmean), maximum temperature (Tmax) and minimum temperature (Tmin) showed a slowdown of the warming trend around 1998, during the period of the global warming hiatus. This was found over both the growing season (GS) and non-growing season (NGS) and suggested a robust warming hiatus over the TP. Due to the differences in trends of Tmax and Tmin, the trend of diurnal temperature range (DTR) also shifted after 1998, especially during the GS temperature. The warming rate was spatially heterogeneous. The northern TP (NTP) experienced more warming than the southern TP (STP) in all seasons from 1982 to 1998, while the pattern was reversed in the period from 1998 to 2015. Water vapour was found to be the main driving force for the trend in Tmean and Tmin by influencing downward long wave radiation. Sunshine duration was the main driving force behind the trend in Tmax and DTR through a change in downward shortwave radiation that altered the energy source of daytime temperature. Water vapour was the major driving force for temperature change over the NTP, while over the STP, sunshine duration dominated the temperature trend. [ABSTRACT FROM AUTHOR]

Climate change is receiving mounting attentions from various fields and phenology is a commonly used indicator signaling vegetation responses to climate change. Previous phenology studies have mostly focused on vegetation greening-up and its climatic driving factors, while autumn phenology has been barely touched upon. In this study, vegetation phenological metrics were extracted from MODIS NDVI data and their temporal and spatial patterns were explored on the Tibetan Plateau (TP). The results showed that the start of season (SOS) has significantly earlier trend in the first decade, while the end of season (EOS) has slightly (not significant) earlier trend. In the spatial dimension, similar patterns were also identified. The SOS plays a more significant role in regulating vegetation growing season length than EOS does. The EOS and driving effects from each factor exhibited spatially heterogeneous patterns. Biological factor is the dominant factor regulating the spatial pattern of EOS, while climate factors control its inter-annual variation. [ABSTRACT FROM AUTHOR]

Mixed halide inorganic perovskite CsPbI 3-x Br x has attracted attention in the field of optoelectronics. As a desirable photoactive material, the application of CsPbI 2 Br in the field of photodetector (PD) remains to be explored. The synergistic passivation strategy based on Ag 2 S quantum dot (QD) aqueous solution improves the morphology of the CsPbI 2 Br perovskite film. At the same time, Ag 2 S/CsPbI 2 Br bulk heterojunction optimizes the energy level arrangement between perovskite and Au electrode, improves the carrier transmission and collection capacity, and thus improves the performance of PD. Ag 2 S/CsPbI 2 Br bulk heterojunction PD has an ultra-low dark current of 7.74 pA, an ultra-fast response speed of 2.95/3.07 μs, and a high switching ratio of 7.67 × 105. This work provides a method for the preparation of high-quality mixed halide perovskite materials and a strategy for the development of high-performance perovskite PDs based on bulk heterojunction. • The synergistic passivation strategy improves the morphology of CsPbI 2 Br. • Ag 2 S/CsPbI 2 Br optimizes the energy level arrangement. • Ultralow I dark of 7.74 pA and ultrafast response of 2.95/3.07 μs. [ABSTRACT FROM AUTHOR]

Understanding vegetation responses to climate change on the Tibetan Plateau ( TP) helps in elucidating the land-atmosphere energy exchange, which affects air mass movement over and around the TP. Although the TP is one of the world's most sensitive regions in terms of climatic warming, little is known about how the vegetation responds. Here, we focus on how spring phenology and summertime greenness respond to the asymmetric warming, that is, stronger warming during nighttime than during daytime. Using both in situ and satellite observations, we found that vegetation green-up date showed a stronger negative partial correlation with daily minimum temperature ( Tmin) than with maximum temperature ( Tmax) before the growing season ('preseason' henceforth). Summer vegetation greenness was strongly positively correlated with summer Tmin, but negatively with Tmax. A 1-K increase in preseason Tmin advanced green-up date by 4 days ( P < 0.05) and in summer enhanced greenness by 3.6% relative to the mean greenness during 2000-2004 ( P < 0.01). In contrast, increases in preseason Tmax did not advance green-up date ( P > 0.10) and higher summer Tmax even reduced greenness by 2.6% K−1 ( P < 0.05). The stimulating effects of increasing Tmin were likely caused by reduced low temperature constraints, and the apparent negative effects of higher Tmax on greenness were probably due to the accompanying decline in water availability. The dominant enhancing effect of nighttime warming indicates that climatic warming will probably have stronger impact on TP ecosystems than on apparently similar Arctic ecosystems where vegetation is controlled mainly by Tmax. Our results are crucial for future improvements of dynamic vegetation models embedded in the Earth System Models which are being used to describe the behavior of the Asian monsoon. The results are significant because the state of the vegetation on the TP plays an important role in steering the monsoon. [ABSTRACT FROM AUTHOR]

• Correlation between albedo and LAI varies with vegetation type and growth stage. • Greening dominates albedo change in arid and semi-arid areas of China. • Land use change affects albedo change under greening by altering canopy structure. Land surface albedo (LSA) is a key parameter in the process of vegetation feedback to climate due to its decisive role in land surface radiation budget. However, our current knowledge on the relationship between LSA and vegetation changes is limited by one-sided attention to sole vegetation growth change or land use/land cover change (LULCC). How vegetation growth or LULCC respectively contributes to LSA change under their interactions remains poorly quantified. In this study, the arid and semi-arid areas of China (ASAC) with profound vegetation changes were selected to tackle this problem. The LSA showed a general downward trend (-0.00009 year−1) during 2000-2018 in response to ASAC's wide-range greening (0.0086 m2m−2year−1). Pairwise comparison analysis revealed that under the same unit of vegetation coverage change, the LSA change magnitude was contracted when grassland was converted to cultivated land or forest land, while the conversions of forest land to other vegetations led to an amplified change magnitude of LSA. Vegetation type directly leads to a difference in LSA change magnitude under greening due to their distinct canopy spectral characteristics. Grassland possesses lower LAI and its pixel-level LSA is more prone to be contaminated by background coverage, while LSA of forest land contains more vegetation canopy signal. In most areas where vegetation type converted, greening dominated LSA change with a contribution rate up to 98.14 %, except for the conversion of grassland to forest land, where LULCC accounted for about 66.38 % of LSA change. This study could improve the estimation of LSA from LAI, which is useful for optimizing vegetation-climate interaction models. [ABSTRACT FROM AUTHOR]

• Correlation between albedo and LAI varies with vegetation type and growth stage. • Greening dominates albedo change in arid and semi-arid areas of China. • Land use change affects albedo change under greening by altering canopy structure. Land surface albedo (LSA) is a key parameter in the process of vegetation feedback to climate due to its decisive role in land surface radiation budget. However, our current knowledge on the relationship between LSA and vegetation changes is limited by one-sided attention to sole vegetation growth change or land use/land cover change (LULCC). How vegetation growth or LULCC respectively contributes to LSA change under their interactions remains poorly quantified. In this study, the arid and semi-arid areas of China (ASAC) with profound vegetation changes were selected to tackle this problem. The LSA showed a general downward trend (-0.00009 year−1) during 2000-2018 in response to ASAC's wide-range greening (0.0086 m2m−2year−1). Pairwise comparison analysis revealed that under the same unit of vegetation coverage change, the LSA change magnitude was contracted when grassland was converted to cultivated land or forest land, while the conversions of forest land to other vegetations led to an amplified change magnitude of LSA. Vegetation type directly leads to a difference in LSA change magnitude under greening due to their distinct canopy spectral characteristics. Grassland possesses lower LAI and its pixel-level LSA is more prone to be contaminated by background coverage, while LSA of forest land contains more vegetation canopy signal. In most areas where vegetation type converted, greening dominated LSA change with a contribution rate up to 98.14 %, except for the conversion of grassland to forest land, where LULCC accounted for about 66.38 % of LSA change. This study could improve the estimation of LSA from LAI, which is useful for optimizing vegetation-climate interaction models. [ABSTRACT FROM AUTHOR]

• Higher spring GPP induced by earlier spring compensated for its summer reductions. • Earlier spring cost soil water earlier, and then strengthened summer heat effects. • These heat effects were offset due to the region-specific characteristics. • Lower temperature alleviated the decreases in summer GPP through decreasing VPD. The knock-on effects between earlier vegetation activities and summer droughts may have important consequences for broad ecological processes. To date, little is known about how the chained effects drive the carbon and water cycles on the Tibetan Plateau (TP). Using the naturally occurring above-mentioned sequential events in spring and summer in 2015 and 2017, we applied the observations at the site, landscape, and regional scales to evaluate the chained effects on the TP. Our findings indicated that higher spring vegetation productivity is caused by early vegetation activities, partially compensated for summer drought-induced loss. Concurrently, increased spring evapotranspiration induced by earlier spring may drain soil water resources earlier, exacerbating summer water restrictions caused mainly by sparse precipitation. This lagged effect of early spring, accompanied by summer drought, significantly increased summer sensible heat flux by 23.2%. Remarkably, the mean air temperature (Ta) was lower than the baseline during drought. This decrease was contributed mainly by lower nighttime Ta, indicating that the region-specific characteristics of the TP could offset the heating effects as mentioned above. The characteristics of high altitude, low air pressure, and thin air could strongly weaken the cloud insulations. More substantial decreases in cloud amount during drought further decreased atmospheric counter radiations, leading to lower mean/nighttime Ta. The simulation results showed that lower mean Ta alleviated the decreases in gross primary productivity by 4.3% through reducing vapor pressure deficit by 5.1%. In conclusion, the present study highlighted the need to comprehensively consider the buffering effects of lower temperature during summer drought to precisely assess the chained effects on the TP. [ABSTRACT FROM AUTHOR]