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The development and implementation of regional protection plans for ecosystem carbon storage services have been recognized as crucial actions for mitigating global climate change. However, the supply areas of carbon sequestration in terms of ecosystem service flows in inland regions are still less evaluated. The goal of this study is to identify the priority-ranked supply areas for carbon sinks. Here, we conducted a case study in the Hexi Region of northwestern China and proposed a framework to quantify the priority supply areas for carbon sinks from the perspective of ecosystem service flows. Firstly, we quantified the carbon service supply and demand areas by combining carbon models (i.e., the Carnegie–Ames–Stanford Approach model and soil respiration models) with socioeconomic and natural factors. Then, we introduced a breaking point formula to estimate ecosystem service flow, specifically focusing on distance or range. Finally, we determined priority supply areas for carbon sinks based on the Zonation model. The results showed that significantly higher carbon sequestration values were detected in the Qilian Mountains, ranging from 2.0 to 3.0 t hm−2, in comparison with desert oasis areas, where the supply values ranged from 0 to 0.01 t hm−2. The urban areas and rural settlements within the study area are characterized by higher values of carbon emissions compared to those in the Qilian Mountains and deserts. The carbon flow analysis demonstrated that the middle and northern parts of the study area, being characterized by lower precipitation and sandy landscapes, were identified as locations with low carbon sequestration fluxes (−2). In addition, the mountainous regions were identified as the main highest priority area for ecosystem carbon sequestration, covering 8.33% of total area of the Hexi Region. Our findings highlighted the importance of the Qilian Mountains in terms of sustaining carbon sequestration service supply in the Hexi Region and targeted ecological protection practices to be implemented going forward.

AbstractObjective The purpose of this meta-analysis was to evaluate the postoperative clinical outcomes of elderly patients who underwent the direct anterior approach (DAA) versus those who received posterolateral approach (PLA) for total hip arthroplasty (THA) in the treatment of femoral neck fractures.Methods An electronic search was conducted in databases including PubMed, Embase, Web of Science, the Cochrane Library, and CNKI from their inception to January 2022. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to assess the effect of DAA compared to PLA for the management of total hip arthroplasty (THA) in elderly patients using the dichotomous or continuous method with a random or fixed-effect model.Results 15 studies involving 1284 patients were included; 640 patients receiving DAA and 644 patients receiving PLA. DAA had a longer surgery duration than PLA [WMD = 9.41, 95% CI (4.64, 14.19), I2=95.5%]; The amount of postoperative drainage [WMD= −3.88, 95% CI (−5.59, −2.17), I2=98.3%], length of incision [WMD= −3.88, 95% CI (−5.59, −2.17), I2=98.3%], blood loss [WMD= −3.88, 95% CI (−5.59, −2.17), I2=98.3%], hospitalization time [WMD= −3.88, 95% CI (−5.59, −2.17), I2=98.3%], and postoperative bedtime [WMD = −5.56,95% CI (−7.11, −4.01), I2=99.0%], were similar between the two groups (p 0.05).Conclusions DAA offers a quicker functional recovery and is less invasive with an earlier return to daily activities in older THA patients than PLA. However, DAA was found to be associated with a high incidence of lateral femoral cutaneous nerve injury and a low incidence of postoperative dislocation.Key messagesThe present study aims to evaluate the clinical outcomes in elderly patients receiving DAA versus PLA for THA in the treatment of femoral neck fractures by mate-analysis.DAA offers a quicker functional recovery and is less invasive with an earlier return to daily activities in older THA patients. No significant difference was observed between the colchicine and comparators in terms of the need for HHS at 1 week, 3 months, and 6 months postoperatively, VAS postoperatively, acetabular anteversion angle, acetabular abduction angle, and complications (wound infection, deep vein thrombosis, and intraoperative fracture).

The mountainous regions of Heihe mainstream in China， is one of the sensitive areas to response the climate change， however， there are few studies on analyzing the possible variation under different climate scenarios in this area.Based on the daily precipitation and mean temperature data from four national standard meteorological stations （which located in or around the study area） and seven climate model outputs from CMIP6， this paper assesses the ability of the CMIP6 Multi-Model ensemble average data in simulation of precipitation and temperature， which including bias correction and not.Furthermore， the predicted precipitation and temperature evolution trends of four SSPs scenarios at different time scales are analyzed by quantitative analysis method.The results show that： （1） The CMIP6 model data has different simulation deviations between precipitation and temperature， and overall， the performance of temperature simulation is better than that of precipitation.After bias correction by MBC， the CMIP6 Multi-Model ensemble mean data can accurately simulate the spatial-temporal characteristics and trends of actual precipitation and temperature.Therefore， it can be considered that the Multi-Model ensemble mean data of CMIP6 with MBC correction can reflect the future climate change trend in study area.（2） Existing differences vary among precipitation and temperature change in the mountainous regions of Heihe mainstream at different time scales.On the seasonal scale， precipitation increases significantly in winter and spring， and temperature increases in spring and autumn.On the annual scale， both future precipitation and temperature show an increasing trend with time， and the trend becomes more significant with increasing radiate forcing of the scenario.On the periods scale， annual precipitation and mean annual temperature increase less in the near to medium period， but more in the medium to far period.（3） At the spatial scale， both precipitation and temperature in the mountainous regions of Heihe mainstream present generally increasing trend from west to east and， there is more rain and higher temperature in the east area than west， so the phenomenon of warmer and wetter in spring will be more obvious in the eastern area than the west.As the climate continues to humidifier and warmer， the possibility of anomalous precipitation and temperature events are likely to increase in the future in the mountainous regions of Heihe mainstream.The extreme climate phenomenon， mainly characterized as the precipitation exploded and the temperature sharply fell， which show a spatial distribution of less in west and more in east.

The effects of land use/cover change (LUCC) on the spatial distribution and change of ecosystem service value (ESV) are still ambiguous, and cannot effectively guide the formulation of land use (LU) management policies based on the concept of harmonious development. Therefore, based on LUCC data from 1980 to 2020, this study adopted the MCE-CA-Markov model to simulate and predict the LUCC under the Business As Usual (BAU) and Ecological Development Priority (EDP) scenarios in 2030 and 2050. The historical and future ESVs as well as the effects of LUCC on ESV change were calculated in Gansu province, Northwest China. The results showed that the LU and ESV of Gansu province changed greatly between 1980 and 2020, with an increase in Forest (568.62 km2), medium- and high-coverage grassland (1517.58 km2), and Construction land (2264.58 km2), and a decrease in Farmland (-730.17 km2) and Unused land (-2858.58 km2), resulting in an increase of 8.162 billion CNY in total ESV. From 2020 to 2050, the LUCC under the EDP scenario will be more conducive to the increase in ESV, with the increment (52.765 billion CNY) being much higher than that under the BAU scenario (3.885 billion CNY). The growth of ESV will mainly result from the expansion of Forest, Water, and Grassland, accounting for 55.4%, 48.6%, and 19.1% of the total ESV increment, respectively, while the decrease in ESV will be attributed to the changes in Farmland and Unused land, accounting for −16.2% and −10.8% of the total ESV increment, respectively. The results have a certain reference for the future LU structure optimization and ecological benefit growth in northwest China.

Study region: Upper reach of the Heihe River basin (UHRB) Study focus: We quantified the potential changes in future climate and streamflow, as well as their corresponding contribution to the annual variations. And the dominant factors of streamflow change were explored in further. Robust multivariate bias correction was applied to correct the outputs of the general circulation method (GCMs) before applying the climate projection. The Soil and Water Assessment Tool model was applied to explore streamflow characteristics under the climate projection of bias-corrected GCMs under four representative emission scenarios (SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5). New hydrological insights for the region: By the end of the 21st century, climate will follow a warming and wetting trend within the basin; the annual streamflow is projected to increase by > 18 % in the 2030 s, and > 36 % in the 2050 s and 2090 s. Overall, the minimum temperature had a positive impact on streamflow in the cold seasons, especially in spring, contributing the most to the annual streamflow increment. When the temperature increase is greater than 5.42 °C, the peak streamflow will shift forward from May to April. Moreover, evapotranspiration will increase with temperature, leading to a decrease in summer streamflow. The results enable us to better understand the climate and streamflow changes at different time scales and provide guidance for the development of climate change response strategies and water resource management planning.

Agricultural carbon emissions are supposed to be a fundamental component of the regional carbon cycle in regions with intense agricultural activities. However, the patterns and controls of agricultural carbon emissions based on the water–land resource coupling effect remain poorly understood in arid inland regions. Thus, we constructed a research framework combining water and land resources with agricultural carbon emissions to assess the linkage of water–land–agricultural carbon emissions in arid inland regions. The agricultural carbon emission measurement model and water–land resource coupling coordination degree model (WLCD) were used for exploring the spatial and temporal patterns of agricultural carbon emissions and water–land elements. The interaction between societal , economic , and ecological factors on agricultural carbon emissions was clarified using the logarithmic mean Divisia index (LMDI). The applicability of the method was verified in the Zhangye oasis in northwest China. The results are as follows: 1) from 2012 to 2019, the agricultural carbon emissions in Zhangye increased first and then declined, with 96% of which mainly coming from chemical fertilizers and plowing; 2) the coupling coordination index of water–land resources in Zhangye increased from 0.3715 in 2012 to 0.5399 in 2019, an increase of 45.33%, indicating a conversion from mild disordered to basic coordination; 3) regarding the effects among the factors, the economic output of agricultural water resource, cropland area per capita, and population (the water and land resource ratio and agricultural carbon emission intensity) exerted positive (negative) impacts on agricultural carbon emissions. Accordingly, it is suggested that the green and low-carbon development strategies for oasis agriculture require a high level of integrated planning and management of water and land resources, as well as comprehensive consideration of low-carbon agriculture and elements related to water and land.

Land-use change is supposed to exert significant effects on the spatio-temporal patterns of ecosystem carbon storage in arid regions, while the relative size of land-use change effect under future environmental change conditions is still less quantified. In this study, we combined a land-use change dataset with a satellite-based high-resolution biomass and soil organic carbon dataset to determine the role of land-use change in affecting ecosystem carbon storage from 1980 to 2050 in the Gansu province of China, using the MCE-CA-Markov and InVEST models. In addition, to quantify the relative size of the land-use change effect in comparison with other environmental drivers, we also considered the effects of climate change, CO2 enrichment, and cropland and forest managements in the models. The results show that the ecosystem carbon storage in the Gansu province increased by 208.9 ± 99.85 Tg C from 1980 to 2020, 12.87% of which was caused by land-use change, and the rest was caused by climate change, CO2 enrichment, and ecosystem managements. The land-use change-induced carbon sequestration was mainly associated with the land-use category conversion from farmland to grassland as well as from saline land and desert to farmland, driven by the grain-for-green projects in the Loess Plateau and oasis cultivation in the Hexi Corridor. Furthermore, it was projected that ecosystem carbon storage in the Gansu province from 2020 to 2050 will change from −14.69 ± 12.28 Tg C to 57.83 ± 53.42 Tg C (from 105.62 ± 51.83 Tg C to 177.03 ± 94.1 Tg C) for the natural development (ecological protection) scenario. By contrast, the land-use change was supposed to individually increase the carbon storage by 56.46 ± 9.82 (165.84 ± 40.06 Tg C) under the natural development (ecological protection) scenario, respectively. Our results highlight the importance of ecological protection and restoration in enhancing ecosystem carbon storage for arid regions, especially under future climate change conditions.

A joint equivalence and difference (JED) test is needed because difference tests and equivalence (more exactly, similarity) tests each provide only a one-sided answer. The concept and underlying theory have appeared numerous times, noted and discussed here, but never in a form usable in workaday statistical applications. This work provides such a form as a straightforward simple test with a step-by-step guide and possible interpretations and formulas. For initial treatment, it restricts attention to a t test of two means. The guide is illustrated by a numerical example from the field of orthopedics. To assess the quality of the JED test, its sensitivity and specificity are examined for test outcomes depending on error risk α, total sample size, sub-sample size ratio, and variability ratio. These results are shown in tables. Interpretations are discussed. It is concluded that the test exhibits high power and effect size and that only quite small samples show any effect on the power or effect size of the JED test by commonly seen values of any of the parameters. Data for the example and computer codes for using the JED test are accessible through links to supplementary material. We recommend that this work be extended to other test forms and multivariate forms. [ABSTRACT FROM AUTHOR]

Water-salt balance is critical for the stable coexistence of salt-affected and groundwater-fed oasis-desert ecosystems. Yet, a comprehensive investigation of how soil salinization and groundwater degradation threaten the coexistence of oasis-desert ecosystems is still scarce, especially under the compounding effects of human activities and climatic changes. Here, we assessed the impacts of irrigated agriculture on hydrological regimes in oasisdesert systems, investigated the spatio-temporal variations of soil salinization in irrigated cropland, and evaluated the implications of the interplays of soil salinization and groundwater degradation on the coexistence of oasis-desert ecosystems in northwestern China, based on meaningful modelling approaches and comprehensive measurements over 1995-2020. The results showed that the irrigation return flow coefficient decreased sharply from 0.21 ± 0.09 in the traditional irrigation period to 0.09 ± 0.01 in the water-saving irrigation period. The continuous drop in groundwater tables and significant degradation of groundwater quality are occurring throughout this watershed. The eco-environmental flows are reaching to their limit with watershed closures (i.e., the drainage from the oasis region into the desert region is being weakened or even eliminated), although these progressions were largely hidden by regional precipitation and streamflow variability. The process of salt migration and accumulation across different landscapes in oasis-desert system is being reshaped, and soil salinization in water-saving agricultural irrigated lands is accelerating with a regional average annual growth rate of 18%. The vegetation in this watershed is degrading, and anthropogenic disturbance accelerates this trend. Our results highlight that environmental stress adaptation strategies must account for resilience maintenance to avoid accelerating catastrophic transitions in oasis-desert ecosystems. Determining the optimal oasis scales and formulating the best irrigation management plans are effective and resilient decision-making ways to maintain the coexistence relationship of oasis-desert ecosystem in drylands. [ABSTRACT FROM AUTHOR]