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Abstract Quantifying terrestrial evapotranspiration (ET) and soil moisture dynamics accurately is crucial for understanding the global water cycle and surface energy balance. We present a novel, long-term dataset of global ET and soil moisture derived from the newly developed Simple Terrestrial Hydrosphere model, version 2 (SiTHv2). This ecohydrological model, driven by multi-source satellite observations and hydrometeorological variables from reanalysis data, provides daily global ET-related estimates (e.g., total ET, plant transpiration, soil evaporation, intercepted evaporation) and three-layer soil moisture dynamics at a 0.1° spatial resolution. Validation with in-situ measurements and comparisons with mainstream global ET and soil moisture products demonstrate robust performance of SiTHv2 in both magnitude and temporal dynamics of ET and soil moisture at multiple scales. The comprehensive water path characterization in the SiTHv2 model makes this seamless dataset particularly valuable for studies requiring synchronized water budget and vegetation response to water constraints. With its long-term coverage and high spatiotemporal resolution, the SiTHv2-derived ET and soil moisture product will be suitable to support analyses related to the hydrologic cycle, drought assessment, and ecosystem health.

Objective: Cemiplimab combined with chemotherapy has emerged as a promising treatment option for advanced non-small cell lung cancer (NSCLC). Accordingly, this study has been conducted to evaluate the cost-effectiveness of this combination therapy in comparison to chemotherapy alone from the perspective of the United States healthcare system. Methods: The present study is based on a partitioned survival model developed from clinical data obtained during the 2-year follow-up of the phase III EMPOWER-Lung 3 part 2 trial. The purpose of this investigation is to estimate the 10-year life expectancy and total healthcare costs of patients with advanced NSCLC by leveraging primary outcomes that evaluated costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER).To establish the willingness-to-pay (WTP) threshold for the analysis, a value of $150,000/QALY was adopted. Sensitivity analysis was performed to determine the impact of varying levels of uncertainty on the results of this study. Results: When compared to chemotherapy alone, the addition of cemiplimab to chemotherapy has been demonstrated to result in an incremental gain of 1.593 QALY at an additional cost of $109351.298. This equates to an incremental cost-effectiveness ratio (ICER) of $68644.883/QALY. One-way sensitivity analyses were conducted on the model, which acknowledged the influence of several parameters, such as subsequent costs, the utility of progressive disease, the cost of best supportive care, the cost of cemiplimab per mg, and the utility of progression-free survival on the outcomes. Nonetheless, none of these parameters yielded an ICER lower than the WTP threshold. Conclusions: From the perspective of the United States healthcare system, the utilization of cemiplimab in combination with chemotherapy as a first-line treatment option for NSCLC appears to be a cost-effective approach as compared to using chemotherapy as a standalone therapy.

To improve our understanding of farmland surface process and agricultural water management in arid oasis area, we analyzed the characteristics of water and heat fluxes at different time scales, and the influence of arid advection and canopy conductance (Gc) on water and heat fluxes at different growth stages. In addition, we used path analysis to study the influence path of environmental factors on latent heat flux (LE). In this paper, the water and heat fluxes were measured by eddy-covariance in 2017. The results were as follows: (1) LE showed multiple peaks, while the other fluxes were basically unimodal shapes at the daily scale. On the whole, the values of daily net radiation (Rn) were maximum, followed by LE, sensible heat flux (H) and soil heat flux (G) at each growth stage. The variation of diurnal G showed obvious lagged effect compared to that of Rn. (2) LE and H accounted for 86% and 14% (respectively) of daytime energy during the whole growing stages, indicating that LE was the main energy consumption item. The contribution of arid advection to daytime LE ranged from 5% to 59% with an average value of 28% at whole growing season. The influence of Gc on LE was stronger at the new shoot and leaf-fall stages than that in the middle growing season. (3) LE was mainly affected by Rn, followed by vapor pressure deficit (VPD) and air temperature (Ta), and the influence degrees of VPD and Ta on LE were similar. Furthermore, the path analysis showed that Rn directly affected LE; VPD and Ta mainly affected LE indirectly through Rn. As a whole, the water and heat fluxes in vineyards of arid desert oasis in Northwest China display significant diurnal and seasonal variations, and the influences of environmental factors on these exists great discrepancies in magnitude and path.

The root distribution and water uptake of irrigated vines (Vitis vinifera L.) in arid oasis areas remain poorly understood, particularly in terms of the variations in water uptake resulting from plant type and growing period. In this study, excavation and soil coring were employed to investigate the root distribution of vines. Meanwhile, the water uptake dynamics of irrigated vines in an arid oasis area were developed using stable isotopes of hydrogen and oxygen in water bodies (δD and δ18O) and in crops and soil water, coupled with a direct inference approach and a linear mixed model (IsoSource). The soil layers were divided into nine layers via hierarchical cluster analysis. The results indicated that the vertical distributions of the total and fine roots of grapevines were mainly in the range of 40–160 cm, accounting for 93.1% (91.2%) and 92.5% (90.0%) of the total root (200 cm) distribution during May and October, respectively. In the horizontal direction, both the total root and fine root systems were mainly distributed within 0–100 cm from the trunk and contributed 81.2% and 79.8% of the total root distribution, respectively. Meanwhile, both the total root weight (length) density and fine root weight (length) density decreased gradually with increasing radial distance from the trunk in the 0–80 cm range. The main water uptake of vines was at 0–40 cm in June, 20–80 cm in July, and 40–100 cm in August. These findings suggest that the main depth of root water uptake increases during the whole growth stage for grapevines in arid oasis ecosystems. This information will help growers to improve irrigation efficiency and provide a data analysis of water conservation in an arid oasis area during water stress.

In this study, a series of naringenin-O-alkylamine derivatives were designed and obtained by introducing an alkylamine fragment into the naringenin skeleton. The in vitro biological activity results revealed that compounds 5f and 7k showed good antioxidant activity with ORAC values of 2.3eq and 1.2eq, respectively. Compounds 5f and 7k were reversible and excellent huAChE inhibitors with IC50 values of 0.91 μM and 0.57 μM, respectively. Moreover, compounds 5f and 7k could inhibit self-induced Aβ1–42 aggregation with 62.1% and 43.8% inhibition rate, respectively, and significantly inhibited huAChE-Aβ1–40 aggregation with 51.7% and 43.4% inhibition rate, respectively. In addition, compounds 5f and 7k were selective metal chelators and remarkably inhibited Cu2+-induced Aβ1–42 aggregation with 73.5% and 68.7% inhibition rates, respectively. Furthermore, compounds 5f and 7k could cross the blood-brain barrier in vitro and displayed good neuroprotective effects and anti-inflammatory properties. Further investigation showed that compound 5f did not show obvious hepatotoxicity and displayed a good hepatoprotective effect by its antioxidant activity. The in vivo study displayed that compound 5f significantly improved scopolamine-induced mice memory impairment. Therefore, compound 5f was a potential multifunctional candidate for the treatment of AD.

Herein, a series of novel O-alkyl ferulamide derivatives were designed and synthesised through the multi-target-directed ligands (MTDLs) strategy. The biological activities in vitro showed that compounds 5a, 5d, 5e, 5f, and 5h indicated significantly selective MAO-B inhibitory potency (IC50 = 0.32, 0.56, 0.54, 0.73, and 0.86 μM, respectively) and moderate antioxidant activity. Moreover, compounds 5a, 5d, 5e, 5f, and 5h showed potent anti-inflammatory properties, remarkable effects on self-induced Aβ1-42 aggregation, and potent neuroprotective effect on Aβ1-42-induced PC12 cell injury. Furthermore, compounds 5a, 5d, 5e, 5f, and 5h presented good blood–brain barrier permeation in vitro and drug-like properties. More interesting, the PET/CT images with [11C]5f demonstrated that [11C]5f could penetrate the BBB with a high brain uptake and exhibited good brain clearance kinetic property. Therefore, compound 5f would be a promising multi-functional agent for the treatment of AD.

Heterotrophic soil respiration and subsidence are enhanced by water table decline, with a meta-analysis estimating that soil respiration in drained peatlands across the globe release 645 Mt carbon per year.

Ecosystem health is the goal of eco-environmental management, and its assessment is necessary for improving regional ecological environments and promoting regional sustainable development. However, previous studies on regional ecosystem health assessment have mainly concentrated on rapidly developing urbanized areas, with very few having been conducted on alpine pastoral regions. Taking the Gannan alpine pastoral region of China as the study area, and based on remote-sensing and GIS technologies, we used entropy methods to calculate the relative weights of several indicators to quantify the uncertainty in the data processing so that the accuracy of the results of the ecosystem health evaluation could be improved. In this study, a new basic-pressure-state-response assessment framework for alpine pastoral ecosystem health assessment is proposed, based on the pressure-state-response. It was found that the levels of ecosystem health of the Gannan pastoral had a spatial distribution pattern that decreased from southwest to northeast, from 2000 to 2015. Notably, the areas of the well and weak health showed a decreasing trend, with more regions tending toward ordinary levels. Among all the assessing indicators, the average value of the pressure indicator was the greatest, with the basic indicator value being the lowest. Our assessment results could be used as a guide for eco-environment managers tasked with taking effective measures to improve the status of the ecosystem health in alpine pastoral regions.

Polyvinyl alcohol (PVA) is widely used in nuclear power plant uniforms, these uniforms are usually sealed with cement after use because they are radioactive, but this will waste land resources. Therefore, to find a simple and effective chemical method to deal with them has become a scientific challenge. Although Fenton process needs further post-treatment, but it has a great advantage on the treatment of PVA fabric, meanwhile, it is one of the most effective methods to dispose organic pollutants at present. In this paper, we investigated the degradation of discarded polyvinyl alcohol (PVA) fabric and PVA (1750) via Fenton process. Several potential factors were evaluated to describe the PVA fabric degrading efficiency and TOC removal rate, such as H2O2 dosage, the molar ratio of H2O2/Fe(NO3)2, initial pH value, reaction temperature, and reaction time. The optimum H2O2 dosage, the molar ratio of H2O2/Fe(NO3)2, initial pH value, reaction temperature, and reaction time were found to be 650 g, 10, 4, 50 °C, and 30 min, respectively. The viscosity-average molecular weight of PVA fabric was degraded from 130,293 to 420. The degrading efficiency and TOC removal rate were 99.96% and 99.97%, respectively. At last, the degradation mechanism and kinetics were studied in this paper.

Abstract Terrestrial ecosystems provide multiple services interacting in complex ways. However, most ecosystem services (ESs) models (e.g., InVEST and ARIES) ignored the relationships among ESs. Process‐based models can overcome this limitation, and the integration of ecological models with remote sensing data could greatly facilitate the investigation of the complex ecological processes. Therefore, based on the Carbon and Exchange between Vegetation, Soil, and Atmosphere (CEVSA) models, we developed a process‐based ES model (CEVSA‐ES) integrating remotely sensed leaf area index to evaluate four important ESs (i.e., productivity provision, carbon sequestration, water retention, and soil retention) at annual timescale in China. Compared to the traditional terrestrial biosphere models, the main innovation of CEVSA‐ES model was the consideration of soil erosion processes and its impact on carbon cycling. The new version also improved the carbon‐water cycle algorithms. Then, the Sobol and DEMC methods that integrated the CEVSA‐ES model with nine flux sites comprising 39 site‐years were used to identify and optimize parameters. Finally, the model using the optimized parameters was validated at 26 field sites comprising 135 site‐years. Simulation results showed good fits with ecosystem processes, explaining 95%, 92%, 76%, and 65% interannual variabilities of gross primary productivity, ecosystem respiration, net ecosystem productivity, and evapotranspiration, respectively. The CEVSA‐ES model performed well for productivity provision and carbon sequestration, which explained 96% and 81% of the spatial‐temporal variations of the observed annual productivity provision and carbon sequestration, respectively. The model also captured the interannual trends of water retention and soil erosion for most sites or basins.

A global warming hiatus occurred during 1998 and 2012 but its effects on phenology are unclear. Here the authors examine the trends in spring and autumn phenology in the northern hemisphere and the effects of the warming hiatus and show that phenology change rate in the northern hemisphere slowed down during the warming hiatus.

Riparian ecosystems fundamentally depend on groundwater, and accurate estimations of groundwater evapotranspiration (ETG) are important for understanding ecosystem functionality and managing regional water resources. Over the past several decades, various methods have been proposed to estimate groundwater evapotranspiration based on water table fluctuations. However, the majority of methods cannot resolve sub-daily variations in ETG. In this study, we proposed a new hydraulic theory-based ETG estimation method at a sub-daily time scale. To evaluate its performance, we employed a variety of measurements (i.e., water table levels, latent heat flux and soil water contents) at a riparian forest (T. ramosissima) in Northwest China from 25 July to 10 October in 2017. The results indicated that the proposed method can successfully estimate ETG at both sub-daily (R2 = 0.75) and daily (R2 = 0.88) time scales, but the variations in the specific yield under different water table conditions should be carefully taken into account. In addition, we investigated the seasonal variations in water uptake source of the riparian plant, and found that it had strong plasticity in water usage during the study period. That is, it consumed approximately equal amounts of soil water and groundwater when soil moisture was available, and tended to consume more groundwater for survival as the soil moisture was depleted. To verify the seasonal patterns of the water uptake of the riparian forest, systematic isotope-based studies are needed in future study.

As an important part of the wetland ecosystem, alpine wetland is not only one of the most important ecological water conservation areas in the Qinghai–Tibet Plateau region, but is also an effective regulator of the local climate. In this study, using three machine learning algorithms to extract wetland, we employ the landscape ecological index to quantitatively analyze the evolution of landscape patterns and grey correlation to analyze the driving factors of Zoige wetland landscape pattern change from 1995 to 2020. The following results were obtained. (1) The random forest algorithm (RF) performs best when dealing with high-dimensional data, and the accuracy of the decision tree algorithm (DT) is better. The performance of the RF and DT is better than that of the support vector machine algorithm. (2) The alpine wetland in the study area was degraded from 1995 to 2015, whereas wetland area began to increase after 2015. (3) The results of landscape analysis show the decrease in wetland area from 1995 to 2005 was mainly due to the fragmentation of larger patches into many small patches and loss of the original small patches, while the 2005 to 2015 decrease was caused by the loss of many middle patches and the decrease in large patches from the edge to the middle. The 2015 to 2020 increase is due to an increase in the number of smaller patches and recovery of original wetland area. (4) The grey correlation degree further shows that precipitation and evaporation are the main factors leading to the change in the landscape pattern of Zoige alpine wetland. The results are of great significance to the long-term monitoring of the Zoige wetland ecosystem.

As an important production base for livestock and a unique ecological zone in China, the northeast Tibetan Plateau has experienced dramatic land use/land cover (LULC) changes with increasing human activities and continuous climate change. However, extensive cloud cover limits the ability of optical remote sensing satellites to monitor accurately LULC changes in this area. To overcome this problem in LULC mapping in the Ganan Prefecture, 2000–2018, we used the dense time stacking of multi-temporal Landsat images and random forest algorithm based on the Google Earth Engine (GEE) platform. The dynamic trends of LULC changes were analyzed, and geographical detectors quantitatively evaluated the key driving factors of these changes. The results showed that (1) the overall classification accuracy varied between 89.14% and 91.41%, and the kappa values were greater than 86.55%, indicating that the classification results were reliably accurate. (2) The major LULC types in the study area were grassland and forest, and their area accounted for 50% and 25%, respectively. During the study period, the grassland area decreased, while the area of forest land and construction land increased to varying degrees. The land-use intensity presents multi-level intensity, and it was higher in the northeast than that in the southwest. (3) Elevation and population density were the major driving factors of LULC changes, and economic development has also significantly affected LULC. These findings revealed the main factors driving LULC changes in Gannan Prefecture and provided a reference for assisting in the development of sustainable land management and ecological protection policy decisions.

We evaluated the performance of three global evapotranspiration (ET) models at local, regional, and global scales using the multiple sets of leaf area index (LAI) and meteorological data from 1982 to 2017 and investigated the uncertainty in ET simulations from the model structure and forcing data. The three ET models were the Simple Terrestrial Hydrosphere model (SiTH) developed by our team, the Priestley–Taylor Jet Propulsion Laboratory model (PT-JPL), and the MODerate Resolution Imaging Spectroradiometer (MODIS) ET algorithm (MOD16). Comparing the observed with simulated monthly ET by the three models over 43 Fluxnet sites, we found that SiTH overestimated ET for forests with mean slope from 1.25 to 1.67, but it performed better than the other two models over short vegetation. MOD16 and PT-JPL models simulated well for forests but poorly in dryland biomes (slope = 0.25~0.55; R2 = 0.02~0.46). At the catchment scale, all models performed well, except for some tropical and high latitudinal catchments, with NSE values lower than 0 and RMSE and MAE values far beyond their mean values. At the global scale, SiTH highly overestimated ET in tropics, while PT-JPL slightly underestimated ET between 30°N and 60°N and MOD16 underestimated ET between 15°S and 30°S. Generally, the PT-JPL provided the better performance than SiTH and MOD16 models. This study also revealed that the estimated ET by SiTH and especially PT-JPL model were influenced by the uncertainty in meteorological data, and the estimated ET was performed better using MERRA-2 datasets for PT-JPL and using ERA5 datasets for SiTH. While the estimated ET by MOD16 were relatively sensitive to LAI data. In addition, our results suggested that the GLOBMAP and GIMMS datasets were more suitable for long-term ET simulations than the GLASS dataset.