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Large‐scale ground deformation in Iceland is dominated by extensional plate‐boundary deformation, where the Mid‐Atlantic Ridge crosses the island, and by uplift due to glacial isostatic adjustment (GIA) from thinning and retreat of glaciers. While this deformation is mostly steady over multiple years, it is modulated by smaller‐scale transient deformation associated with, for example, earthquakes, volcanic unrest, and geothermal exploitation. Here, we combine countrywide Sentinel‐1 interferometric synthetic aperture radar (InSAR) data (from six tracks) from 2015 to 2021 with continuous Global Navigation Satellite System observations to produce time series of displacements across Iceland. The InSAR results were improved in a two‐step tropospheric mitigation procedure, using (a) global atmospheric models to reduce long‐wavelength and topography‐correlated tropospheric signals, and (b) modeling of the stochastic properties of the residual troposphere. Our results significantly improve upon earlier countrywide InSAR results, which were based on InSAR stacking, as we use more data, better data weighting, and advanced InSAR corrections to produce time series of ground displacements instead of just velocities. We fuse the three ascending and three descending track results to estimate maps of East and Up velocities, which clearly show the large‐scale extension and GIA deformation. Using revised plate‐spreading and GIA models, based on these new ground velocity maps, we remove the large‐scale and steady deformation from the InSAR time series and analyze the remaining transient deformations. Our results demonstrate the importance of (a) mitigating InSAR tropospheric signals over Iceland and of (b) solving for time series of deformation, not just velocities, as multiple transient deformation processes are present. Plain Language Summary: Iceland is continuously deforming due to multiple processes across the country, including both large‐scale plate spreading and smaller‐scale transient processes. In this paper, we use 7 years (2015–2021) of Sentinel‐1 interferometric synthetic aperture radar (InSAR) data to map in high‐resolution the ground displacements in Iceland to study both the long‐term and short‐term geodynamic activity. Horizontal movements associated with plate spreading and uplift caused by thinning and retreat of glaciers dominate the observed displacement field. After removing the large‐scale movements from the displacement results using modeled displacements, we analyze local deformation associated with earthquakes, slope instability, and volcanic and geothermal processes. Our study demonstrates the capability of InSAR in studying nationwide spatio‐temporal geodynamic processes. Key Points: Time series of countrywide displacements over Iceland from 2015 to 2021 derived by integrating Sentinel‐1 interferometric synthetic aperture radar (InSAR) and GPS observationsA two‐step InSAR tropospheric correction method used to mitigate both short‐wavelength and long‐wavelength tropospheric effectsResults dominated by plate spreading and glacial isostatic adjustment with numerous other smaller‐scale signals [ABSTRACT FROM AUTHOR]

Earthquake‐triggered slow‐moving landslides are not well studied mainly due to a lack of high‐resolution in‐situ geodetic observations both in time and space. Satellite‐based interferometric synthetic aperture radar (InSAR) has shown potential in landslides applications, however, it is challenging to detect earthquake‐triggered slow‐moving landslides over large areas due to the effects of post‐seismic tectonic deformations, atmospheric delays, and other spatially propagated errors (e.g., unwrapped errors caused by decorrelation noises). Here, we present a novel InSAR phase‐gradient‐based time‐series approach to detect slow‐moving landslides that triggered by the 2016 Mw 7.8 Kaikōura earthquake. Twenty‐one earthquake‐triggered large (>0.1 km2) slow‐moving landslides are detected and studied. Our results reveal decaying characteristics of the temporal evolutions of these landslides, that averagely 3.9 years after the earthquake, their post‐seismic velocity will decay by 90% to reach approximately the pre‐seismic level. Our study opens new perspectives for understanding mass balance of earthquakes and helps reduce associated hazards. Plain Language Summary: Large shallow earthquakes in mountainous regions can trigger widespread landslides that cause major damage to infrastructure. Such landslides are typically identified using aerial imagery, optical satellite images, or fieldwork as such landslides tend to be associated with "fresh" scars and deposits of debris. However, another type of landslides, that are triggered by earthquake but move slowly, are difficult to find and monitor. Satellite‐based interferometric synthetic aperture radar (InSAR) provides an opportunity to monitor slow‐moving landslides, however, given the subtle and localized signals in the InSAR maps, the landslide displacements are easily contaminated by other signals in InSAR. To address this problem, we developed a new InSAR‐phase‐gradient based time‐series method. Using our new method, we find 21 large earthquake‐triggered slow‐moving landslides with average area of 0.84 km2. Through studying the spatio‐temporal displacements of these landslides, we find their movements gradually recover to pre‐seismic level in the years after the earthquake. Our study help to better understand the mechanism of earthquake triggered landslides, and thus contribute to reduce associated hazards. Key Points: A new interferometric synthetic aperture radar phase‐gradient based time‐series approach used to detect earthquake‐triggered slow‐moving landslidesTwenty‐one slow‐moving landslides triggered by the 2016 Mw 7.8 Kaikōura earthquake are detected and monitoredOur results reveal decaying characteristics of post‐seismic velocity of the earthquake‐triggered slow‐moving landslides [ABSTRACT FROM AUTHOR]

In this study, the flower-shaped Bi2S3/g-C3N4-2.6 heterojunction obtained by solvothermal method and its photocatalytic degradation efficiency of rhodamine B (RhB) and tetracycline (TC) in aqueous solution within 40 min is as high as 98.8% and 94.6%. For RhB degradation, the photocatalytic reaction rate constant (k) of Bi2S3/g-C3N4-2.6 is approximately 1.8 and 45.5 times that of Bi2S3 and g-C3N4. For TC, k is 3.1 and 2.4 times that of Bi2S3 and g-C3N4, respectively. The key to determining the high catalytic activity of Bi2S3/g-C3N4 lies in the formation of a good heterojunction between Bi2S3 and g-C3N4, which accelerates the electron transfer rate between the heterojunction interface and effectively avoids electron–hole recombination. The effects of catalyst dosage, different pH values, inorganic anions, and capture agents on the photodegradation performance of RhB were investigated. The results show that the catalyst dosage is 1.33 g/L, and the solution pH is in the range of 5–9, which has the best removal effect on pollutants, and the isolation of holes (h+) with strong oxidizing ability promotes the collapse of pollutant molecules. Combined with electrochemical tests, a possible degradation mechanism was advised. [ABSTRACT FROM AUTHOR]

Innovation strategies for the promotion of solid waste recycling technologies include not only new technologies for resource utilization of solid waste but also sustainable business models to support the adoption of these technologies. This study presents how to incorporate the determinant factors affecting technology promotion and business strategy into a sustainable business model for the promotion of solid waste recycling technologies. A systematic literature review summarizes the determinant factors affecting the aforementioned promotion, including market‐, policy‐, company‐, and technology‐related factors. Combined with the theoretical background of the sustainable business model, this study analyzes that for the promotion of solid waste recycling technologies from value dimensions (value proposition, value creation & delivery, and value capture) and sustainability dimensions (economic, social, and environmental). We confirm the importance of incorporating determinant factors into the sustainable business model from the analysis of the Daye Non‐Ferrous Metal Recycling Park. Our case study proposes that innovation of the sustainable business model needs to drive changes in business strategy. To promote the aforementioned technologies, we propose an Internet‐based technology service platform as the core strategy of the sustainable business model. As the private sector, technology companies can make full use of technological innovation, public policies, and the market environment to achieve and develop sustained competitive advantages through an Internet‐based platform and to effectively enhance the promotion of solid waste recycling technologies and help achieve sustainable development. [ABSTRACT FROM AUTHOR]

A long-strip differential interferometric synthetic aperture radar (DInSAR) measurement based on multi-frame image mosaicking is currently the realizable approach to measure large-scale ground deformation. As the spatial range of the mosaicked images increases, the nonlinear variation of ground ocean tidal loading (OTL) displacements is more significant, and using plane fitting to remove the large-scale errors will produce large tidal displacement residuals in a region with a complex coastline. To conveniently evaluate the ground tidal effect on mosaic DInSAR interferograms along the west coast of the U.S., a three-dimensional ground OTL displacements grid is generated by integrating tidal constituents' estimation of the GPS reference station network and global/regional ocean tidal models. Meanwhile, a solid earth tide (SET) model based on IERS conventions is used to estimate the high-precision SET displacements. Experimental results show that the OTL and SET in a long-strip interferogram can reach 77.5 mm, which corresponds to a 19.3% displacement component. Furthermore, the traditional bilinear ramp fitting methods will cause 7.2~20.3 mm residual tidal displacement in the mosaicked interferograms, and the integrated tidal constituents displacements calculation method can accurately eliminate the tendency of tidal displacement in the long-strip interferograms. [ABSTRACT FROM AUTHOR]

The construction of ecological barriers and ecological security patterns is an important way of maintaining regional ecological security in landscape ecology. However, there is still no consensus on the concept and connotation of ecological barriers, and the zoning and adaptive management of ecological sources are rarely considered in the construction of ecological security patterns. This study uses the terrestrial ecosystem of Bohai Bay, China as a study area, and the identification and zoning of ecological sources in the ecological security pattern are achieved by combining an ecosystem service assessment with an ecological risk assessment, and on this basis, ecological barriers are identified to optimize the structure and function of ecological sources. The minimum cumulative resistance model is used to identify ecological corridors and ecological strategic nodes and to construct an ecological security pattern based on the modified ecological sources. The results demonstrate that firstly, 2873.25 km2 was identified as the ecological source, accounting for 14.28% of the total. Secondly, there are three large ecological barrier zones and nine ecological barrier cells with a total area of 1173.06 km2, accounting for 40.83% of the ecological sources. Thirdly, a total of 35 ecological corridors were extracted, and 32 ecological strategic nodes were marked, mainly distributed at the intersection and branches of important ecological corridors. An ecological security pattern construction system was formed with the collection of ecological source selection, ecological barrier identification, ecological resistance surface construction, and ecological corridor extraction. Fourthly, the concept and connotation of ecological barriers was analyzed, and the complementary relationship between ecological barriers and ecological security patterns in terms of structure and function is discussed. This study enriches the definition and connotation of ecological barriers, provides a new framework for identifying the ecological security patterns, and provides scientific guidance for ecological protection and management in coastal areas. [ABSTRACT FROM AUTHOR]

Interferometric Synthetic Aperture Radar (InSAR) data are increasingly being used to map interseismic deformation with ascending and descending‐orbit observations allowing for resolving the near‐east and vertical displacement components. The north component has, however, been difficult to retrieve due to the limited sensitivity of standard InSAR observations in that direction. Here, we address this problem by using time‐series analysis of along‐track interferometric observations in burst‐overlap areas of the Terrain Observation with Progressive Scan imaging mode of the Sentinel‐1 radar satellites. We apply this method to the southern part of the near‐north striking Dead Sea transform fault to show that the ∼5 mm/year relative motion is well recovered. Furthermore, the results indicate the locking depth of the fault decreases toward the south as it enters the transtensional Gulf of Aqaba basin. Our results show that time‐series analysis of burst‐overlap interferometric observations can be used to obtain meaningful interseismic deformation rates of slow‐moving and northerly striking faults. Plain Language Summary: Measurements of interseismic deformation near plate‐boundary faults are used to estimate how large and how often major earthquakes are likely to occur and thus provide crucial input for regional seismic hazard assessments. Geodetic GPS data have primarily been used for this task, but increasingly Interferometric Synthetic Aperture Radar (InSAR) observations from satellites have provided useful information, particularly in areas where GPS observations are scarce. However, InSAR observations are only sensitive to the east and vertical components of deformation, but not to the north component, and are thus of limited use to study northerly striking earthquake faults. To address this problem, we combine an advanced processing technique called burst‐overlap interferometry (BOI) with time‐series analysis of a large data set to retrieve millimeter per year details of north‐south deformation. We apply this method to the north‐striking southern Dead Sea fault to show that the earthquake hazard decreases toward the south as the fault enters Gulf of Aqaba and approaches the Red Sea rift. Our study demonstrates that this method of BOI time‐series analysis allows mapping the interseismic deformation of slow‐moving and north‐striking faults. Key Points: Along‐track Sentinel‐1 burst‐overlap interferometric time‐series analysis used to derive interseismic deformation ratesThis method yields mm/year interseismic velocities in the north‐south directionThe results indicate a decreasing locking depth of the southern Dead Sea fault toward the Red Sea rift [ABSTRACT FROM AUTHOR]

Tropospheric delays are still the main error source of satellite‐based Interferometric Synthetic Aperture Radar (InSAR) mapping of Earth's surface movements. Recent studies have demonstrated the potential of global atmospheric models (GAMs) in reducing InSAR tropospheric delays. However, the importance of appropriate interpolation and weighting strategies in GAM corrections has largely been overlooked. Here we present a new GAM‐based tropospheric correction method that incorporates spatial stochastic models of the troposphere into the weighting strategy of the correction. The method determines the correlation between a pixel of interest and neighboring GAM grid locations (3D) according to the spatial variability of the tropospheric random field, instead of subjectively using an inverse distance method, a local spline function, or other standard interpolation scheme. Also, our new method considers horizontal heterogeneities of the tropospheric field by estimating the integral of the tropospheric delays along the satellite line‐of‐sight (LOS) direction, instead of calculating projected zenith‐delays. The method can be used with any GAM, but we here implement it with the latest ECMWF (European Center for Medium‐Range Weather Forecasts) ERA5 reanalysis products. We validate the new method with hundreds of Sentinel‐1 images from 2015 to 2020 over the island of Hawaii, a location with variable topography, surface conditions, local climate, and deformation, and explore the tropospheric corrections for both interferograms and time‐series analysis products (deformation velocities and time‐series solutions). Compared with other GAM corrections (PyAPS, d‐LOS, and GACOS), our new method yields a larger reduction of the average standard deviation of the corrected interferograms, i.e., from 2.55 to 1.91 cm, instead of 2.47 cm (PyAPS), 2.44 cm (d‐LOS), and 2.10 cm (GACOS). Also, a larger fraction of 87% of the interferograms (243 out of 280) is improved, compared with 52%, 53%, and 66% for the other GAM corrections, respectively. These results demonstrate the importance of considering (1) tropospheric stochastic models in GAM corrections, (2) horizontal heterogeneities when estimating the LOS delays, and (3) tropospheric delays when mapping long‐wavelength or small‐magnitude deformations using InSAR. Key Points: An improved InSAR troposphere correction method proposed, based on Global Atmospheric Models (GAM), that considers spatial stochastic properties of the troposphere at different altitude levels for better weighting the GAM samplesComparisons with three other GAM corrections (PyAPS, d‐LOS, and GACOS) show a significant reduction in average standard deviation of corrected interferograms and better time‐series analysis resultsThe results demonstrate the importance of considering horizontal heterogeneities and spatial stochastic models of the troposphere when using GAM corrections [ABSTRACT FROM AUTHOR]

Previous research has demonstrated several successful meteorological applications of interferometric synthetic aperture radar (InSAR) by mapping high‐resolution precipitable water vapor (PWV) over large areas with satisfactory precision (e.g., 1–2 mm). InSAR, however, can only measure temporal changes in the PWV, that is, the differential PWV (ΔPWV) between two SAR acquisition epochs. The construction of absolute PWV maps using InSAR observations remains an intractable problem. We present here a new method for constructing high‐resolution PWV maps by fusing InSAR and global positioning system (GPS) measurements. Our method involves: (1) extracting temporal differences in the zenith wet delays (ΔZWD) from InSAR observations with the assistance of synchronous GPS measurements, and (2) using a constrained minimum variance estimator (CMVE) to construct the high‐resolution maps of the absolute ZWDs by fusing the InSAR‐ΔZWD and the GPS‐ZWD samples, and finally (3) transforming the high‐resolution ZWDs to PWVs using an elevation‐dependent proportionality. Only a single interferogram was needed in our method, so we did not use any temporal (i.e., time‐series) hypotheses, for example, we did not assume that the average value of the temporal turbulent ZWDs was equal to zero. We validated the new method over the Southern California region using four Sentinel‐1 interferograms related to eight SAR images acquired in different seasons and in different years. We also used synchronous GPS measurements from the Southern California integrated GPS network. Eight high‐resolution maps of PWVs related to the eight SAR acquisitions were generated, covering ∼250 km in area at a ∼160 m spatial resolution. Comparisons between the CMVE method and the other two methods (GPS‐only‐based interpolation and time‐series InSAR stacking) were conducted. Experimental results showed that the CMVE method performed significantly better than conventional methods for constructing high‐resolution PWV maps, which is of great interest to a wide community of geophysicists and meteorologists. Key Points: A new composed model to remove hydrostatic delays and orbital errors from interferometric synthetic aperture radar (InSAR) measurements to extract the wet delaysA constrained minimum variance estimator to reconstruct high‐resolution maps of the absolute zenith wet delay (ZWD) by fusing InSAR‐ΔZWD and GPS‐ZWDThe new method is compared with both the global positioning system (GPS) interpolation method and the Stacking InSAR method [ABSTRACT FROM AUTHOR]

Despite the many applications of time series interferometric synthetic aperture radar (TS-InSAR) techniques in geophysical problems, error analysis and assessment have been largely overlooked. Tropospheric propagation error is still the dominant error source of InSAR observations. However, the spatiotemporal variation of atmospheric effects is seldom considered in the present standard TS-InSAR techniques, such as persistent scatterer interferometry and small baseline subset interferometry. The failure to consider the stochastic properties of atmospheric effects not only affects the accuracy of the estimators, but also makes it difficult to assess the uncertainty of the final geophysical results. To address this issue, this paper proposes a network-based variance–covariance estimation method to model the spatiotemporal variation of tropospheric signals, and to estimate the temporal variance–covariance matrix of TS-InSAR observations. The constructed stochastic model is then incorporated into the TS-InSAR estimators both for parameters (e.g., deformation velocity, topography residual) estimation and uncertainty assessment. It is an incremental and positive improvement to the traditional weighted least squares methods to solve the multitemporal InSAR time series. The performance of the proposed method is validated by using both simulated and real datasets. [ABSTRACT FROM AUTHOR]

Carbon sequestration of blue carbon ecosystems worldwide is as high as 237.6 Tg C/a. China is one of the countries with the most resources of blue carbon, with carbon sequestration of 0.835 Tg C/a. To develop blue economy and facilitate the fulfillment of carbon neutrality, it is of great significance for China to build the blue carbon trading market (BCTM). This paper aimed to improve the participation probability of stakeholders to construct an effective BCTM through evolutionary game theory. First, we constructed a tripartite evolutionary game model including the governments, the suppliers of blue carbon (SBC) and the demanders of blue carbon (DBC), based on the corresponding cost and benefit in BCTM. To further reveal the factors affecting the cooperation of above parties, we analyzed the sensitivity of the stakeholders through five parameters, i.e., proportion of subsidies, unit carbon tax, blue carbon credits, unit price of blue carbon credits, and the cost of carbon emission reduction unit. To verify the game model, a case study of blue carbon credits of mangrove trading was performed. The main conclusions are as follows. In the initial stage of BCTM, the governments need to play a leading role in regulating and incentivizing motivation of the SBC and DBC. Subsidies and carbon taxes are conducive to promoting BCTM to develop into the middle stage. In the middle stage, price and quota of BC credits are two primary parameters to affect the evolutionary results of above three groups. Thus, it's necessary for the governments to adjust these parameters in time. When the trading scale and operation mode of BCTM approaching stable, the market will enter into the mature stage. Then, the governments can reduce subsidies to save fiscal expenditure and lessen the intervention, so as to gradually withdraw from the market. The above conclusions can provide a theoretical basis and reference for the construction of efficient BCTM and promote the integration of blue carbon into the carbon market in China. [Display omitted] [ABSTRACT FROM AUTHOR]

Time series of ground subsidence can not only be used to describe motion produced by various anthropocentric and natural process but also to better understand the processes and mechanisms of geohazards and to formulate effective protective measures. For high-accuracy measurement of small baseline subset interferometric synthetic aperture radar (SBAS-InSAR), atmospheric turbulence and decorrelation noise are regarded as random variables and cannot be accurately estimated by a deterministic model when large spatio-temporal variability presents itself. Various weighting methods have been proposed and improved continuously to reduce the effects of these two parts and provide uncertainty information of the estimated parameters, simultaneously. Network-based variance-covariance estimation (NVCE) and graph theory (GT) are the two main weighting methods which were developed on the basis of previous algorithms. However, the NVCE weighting method only focuses on the influence of atmospheric turbulence and neglects the decorrelation noise. The GT method weights each interferogram in a time series by using the Laplace transformation. Although simple to implement, it is not reasonable to have an equal weight for each pixel in the same interferogram. To avoid these limitations, this study presents a new weighting method by considering the physical characteristics of atmospheric turbulence and decorrelation noise in SBAS-InSAR images. The effectiveness of the proposed method was tested and validated by using a set of simulated experiments and a case study on a Hawaiian island. According to the GPS-derived displacements, the average RMSE of the results from the new weighting method was 1.66 cm, indicating about an 8% improvement compared with 1.79, 1.80 and 1.80 cm from the unweighted method, the NVCE method and the GT method, respectively. [ABSTRACT FROM AUTHOR]

The spatiotemporal crustal non-tectonic deformation caused by ocean tidal loading (OTL) can reach the centimeters scale in coastal land areas. The temporal variation of the site OTL displacements can be estimated by the global positioning system (GPS) technique, but its spatial variation needs to be further determined. In this paper, in order to analyze the spatial characteristics of the OTL displacements, we propose a multi-scale decomposition method based on signal spatial characteristics to derive the OTL displacements from differential interferometric synthetic aperture radar (D-InSAR) measurements. The method was tested using long-term advanced synthetic aperture radar (ASAR) data and GPS reference site data from the Los Angeles Basin in the United States, and we compared the results with the FES2014b tide model. The experimental results showed that the spatial function of the OTL displacements in an ASAR image can be represented as a higher-order polynomial function, and the spatial trends of the OTL displacements determined by the InSAR and the GPS techniques are basically consistent with the FES2014b tide model. The root-mean-square errors of the differences between the spatial OTL displacements of these two methods and the FES2014b tide model are less than 0.8 mm. The results indicate that the OTL displacement extracted from InSAR data can accurately reflect the spatial characteristics of the OTL effect, which will help to improve the spatial resolution and accuracy of the OTL displacement in coastal areas. [ABSTRACT FROM AUTHOR]

Calliptamus barbarus Costa is a species in genus Calliptamus, belonging to the Calliptaminae, Acrididae, Orthoptera. In the present study, the mitogenome of C. barbarous was determined and annotated to better identify C. barbarous and other related species. The mitogenome was 15,686 bp in length and encoded 37 genes, including 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The nucleotide composition analysis of the mitogenome showed a strong bias of A/T, with A+T content of 72.7%, being similar to other reported mitogenomes. All the 13-PCGs used typical start codons of ATN and stop codons of TAA/G. All of the transfer RNA genes had typical clover-leaf structure except the missing dihydrouidine (DHU) arm of tRNASer1. Interestingly, we observed two overlapped but conserved regions between ATP8 and ATP6 genes, ND4 and ND4L genes. The results of Ka/Ks implied that CytB is more conservative than COX1. Phylogenetic analyses based on the 13-PCGs from 30 species indicated strong support for the monophyly of Acridoidea and represented the main topology as follows: (Oedipodinae+ (Acridinae+ (Gomphocerinae +((Calliptaminae+Catantopinae) +(Oxyinae+Melanoplinae))))). The phylogenetic relationship indicated that the molecular taxonomy of C. barbarous was consistent with the current morphological classification. The data in the present study will further enrich the mitogenome database of Acridoidea and provided useful clues for further research of C. barbarous on the mitogenome evolution and diversification of Calliptamus.