High Erosion Research Articles

Toward better targeting of mitigation measures for reducing phosphorus losses from land to water: Andrew Sharpley's legacy in Norway and Sweden.

Nordic agriculture faces big challenges to reduce phosphorus (P) loss from land to water for improving surface water quality. While understanding the processes controlling P loss and seeking for P mitigation measures, Norwegian and Swedish researchers have substantially benefited from and been inspired by Dr. Andrew Sharpley's career-long, high-standard P research. Here, we demonstrate how Sharpley and his research have helped the Nordic researchers to understand the role of cover crops in cold environmental conditions, best manure P management practices, and ditch processes. His work on critical source area (CSA) identification and site assessment tool development have also greatly inspired our thinking on the targeting of mitigation measures and the contextualizing tools for Nordic climate, landscape, and soils. While reflecting on Sharpley's legacy, we identify several needs for Norwegian and Swedish P research and management. These include (1) tackling the challenges caused by local/regional unevenness in livestock density and related manure management and farm P surpluses, (2) identifying CSAs of P loss with high erosion risk and high P surplus, (3) obtaining more high-resolution mapping of soils with low P sorption capacity both in the topsoil and subsoil, (4) improving cross-scale understanding of processes and mitigation measures and proper follow-up of applied mitigation measures, and (5) increasing collaborations of researchers with farmers and farmers' advisory groups and watershed groups by developing high-quality educational courses and extension materials. The needs should be addressed in the context of the challenges and opportunities created by climate change.

Investigation of Bridge Scour Mitigation with Nature Binding Materials: Biopolymers

The use of biopolymers to tackle geotechnical problems is an essential step toward the development of sustainable geotechnical systems. The strength and erosion resistance of biopolymer-treated Hot Coffee soil sampled from the bridge site in Jackson, Mississippi were examined in this research. The optimum biopolymer concentration and moisture content were tested for Agar Gum, Xanthan Gum, and Guar Gum treatment of Hot Coffee soil, respectively. The mechanical behavior and erosion resistance of biopolymer-treated soil samples were evaluated through the unconfined compressive strength test, splitting tensile test, triaxial test, and pocket erodometer test. The results indicated that all three biopolymers improved Hot Coffee soil strength, but Guar Gum improved soil unconfined compressive and tensile strength greatly. The addition of 1% Guar Gum can improve the unconfined compression stress (UCS) and split the tensile strength of Hot Coffee soil to roughly 4,000 kPa and 600 kPa, respectively. At the same time, the cohesion of Hot Coffee soil treated with biopolymer was enhanced. The cohesion of the soil treated with 1.5% Xanthan Gum increased from 0 to 41.5 kPa. In addition, the erosion resistance of biopolymer-treated soil was also increased. With a 1.5% Xanthan Gum addition, the erosion resistance level of Hot Coffee soil reduced from very high erodibility to medium erodibility. Therefore, biopolymers have great potential for bridge scour mitigation.

Regulating mechanical and anti-erosion wear properties of ZTA ceramics by adjusting Y2O3 content

High fracture toughness and low erosion wear play key roles in improving the working reliability and service life of erosion-resistant ZTA ceramic parts (ZTA-CPs). To reconcile the hardness, fracture toughness and erosion wear resistance, the Y2O3 content of ZTA-ceramics with 20 wt% ZrO2 (Z20TA) was successfully controlled by adjusting the mass ratio of commercially available m-ZrO2 and 3Y–ZrO2 powders in the initial compositions in this paper. Significantly, the fracture toughness and Vickers hardness of Z20TA bulk ceramics with different Y2O3 content can reach up to 5.35 MPa m1/2 and 15.82 GPa, and the erosion wear volume can be reduced to as low as 0.019 cm3, higher than those of Z20TA-ceramic parts by 5∼22 %, 12–19 % and 24–47 %, respectively. This novel Y2O3 content adjustment method is feasible for the industrial level mass production of anti-erosion wear high-performance ZTA parts, promoting the industrial development and wider application of erosion-resistant ceramic parts.

Determinants of mangrove seedling survival incorporated within hybrid living shorelines

Many communities around the world face a pressing need to increase coastal resilience due to widespread coastal erosion and rising sea levels. Natural habitats such as mangrove forests have been increasingly recognised for their ability to protect coastlines through wave attenuation and sediment deposition and stabilisation. However, attempts to rehabilitate mangroves for coastal protection have been met with difficulties due to smaller windows of opportunity for seedling survival at sites experiencing high wave energy and erosion. In this study, we planted the mangrove Avicennia alba in planting pods (n = 348) deployed on an eroding shoreline in Singapore and compared survival to those planted in control plots. Several ecological factors that might influence A. alba survival were manipulated, such as life stage during planting, reduction of wrack accumulation, elevation, and post-planting maintenance. We found that mangrove pods significantly increased mangrove seedling survival. Planting older A. alba seedlings, reducing wrack accumulation, and deploying the pods at a higher elevation further increased survival. Additionally, pressure gauges deployed showed that the pods were able to attenuate wave energy, thus providing hydrodynamic shelter to mangroves. Hybrid living shorelines have the potential to facilitate mangrove rehabilitation through the alleviation of adverse environmental conditions, but other ecological requirements for mangrove seedling survival will need to be met to optimise rehabilitation efforts.

Lake total suspended matter retrieval by wind speed: A machine learning model trained by time-series satellite imagery

This study aims to develop an affordable and continuous method for monitoring water quality in arid, remote areas with high erosion rates. It presents a hypothesis that establishes a link between the concentration of Total Suspended Matter (TSM) and wind speed, emphasizing its ecological importance in lakes with dry conditions and high erosion rates. Building upon this hypothesis, the study introduces Wind2TSM-Net, a machine learning model that effectively bridges between different regression and neural network algorithms. This model connects on-site wind speed measurements with TSM data obtained through a physically remote sensing approach. It accurately predicts TSM concentration values, overcoming challenges such as cloud interference and reducing reliance on satellite imagery. The model was applied to Iran's Chah-Nimeh Reservoirs (CNRs) as a case study in an arid and remote area. The results revealed a significant correlation between TSM concentration and wind speed measurements, with impressive performance metrics (coefficient of determination (R2) = 0.88, root mean square error (RMSE) = 1.97 g/m3, mean absolute error (MAE) = 1.33). These findings highlight the effectiveness of Wind2TSM-Net in monitoring TSM values in remote and dry regions, particularly during extreme weather conditions when on-site measurements are impractical or cloud cover obstructs satellite observations.

Properties of shape memory polyimide composites with continuous “brick-and-mortar” layered structure: High flame retardancy, ablation resistance, and high mechanical properties

Shape memory polymer (SMP) is a type of smart materials mostly working below 200 ℃, which is difficult to be applied in the ultra-high temperature, even 1000 ℃. Herein, we have prepared shape memory polyimide composites (SMPIC) inspired by nacre “brick-and-mortar” layered structure. The SMPIC has the flame-retardant grade of V0 and the limiting oxygen index of 53.1% when the flame retardants amount is 20%. Besides, it has excellent resistance to high temperature airflow erosion, and the mass ablation ratio is 0.0053 g/s. After rapid thermal processing at 1000 ℃, the mechanical strength is 100 MPa, and the strength retention ratio is 103.3%. Also, the simple actuator can overturn iron blocks that are more than 8 times of its own weight, thus, the smart composite has huge application prospects in the high temperature environment, such as active morphing re-entry parachute, which provides reference for lightweight smart structures.

Development of machine learning models for the prediction of erosion wear of hybrid composites

AbstractThis article reports on development of an adaptive framework for predicting the erosion performance of polymer composites using certain statistical and machine learning (ML) models. For this, ramie‐epoxy composites reinforced with variations (0–30 wt%) of sponge iron slag (an iron industry waste) are considered. The composites are fabricated and then subjected to high temperature solid particle erosion wear trials following Taguchi's L27 orthogonal array. The effects of different control factors on the erosion rate in an interactive environment are appraised by analysis of variance (ANOVA) which reveals the filler content as the most significant factor contributing 66.21%, followed by impact velocity (22.86%) and impingement angle (2.28%). A regression model based on the input–output parameters obtained from experimentation is constructed for prediction of erosion rate. Further, four predictive models using different machine learning algorithms are also proposed to predict the erosion rate of the composites. The feasibility and performance of each ML model is assessed using appropriate performance metrics. Among all the models, the gradient boosting machine model is found to be the most reliable model exhibiting the highest prediction accuracy and least errors.Highlights Development of novel class of composites reinforced with sponge iron slag. Database creation based on erosion wear experimentation on the composites. Data‐driven modeling for prediction of erosion rates using machine learning. Comparison of performance of different models and identifying the best one.

The Role of Mangrove Forests in The Coast and Dykes West Sea Zone Protection: A Case Study in Kien Giang and Ca Mau Provinces

Purpose: The study aimed to provide a picture total of the forest and erosion status of the beach and dykes of Kien Giang and Ca Mau. Method: There are 18 sample plots for testing. The map also includes 68 survey plots that are predefined and used as a basis for positioning in the field. The measurement indicators include tree species identification. Results and conclusion: The level of erosion in Ha Tien’s forests varies based on tree density and environmental factors. The forest with no erosion has a thickness of 9,600 trees/ha and a stem diameter of 19 cm, while the extremely erosion forest has 2,000 trees/ha and a stem diameter of 6 cm. Topographically, Ha Tien has little erosion, while U Minh is a low-lying area with high erosion. Erosion levels are 1-2 in January-April, 4-5 in May-October and 3 in November-December. Currently, the section is divided into 28 sub-sections, with Kien Giang having 23. One sub-section is level 1, 11 sub-sections are level 2, 1 is level 3, 3 are level 4, and 3 are level 5. In Ca Mau, two sub-sections are level 4, and 3 are level 5. Implications of the research: With climate change and rising sea levels, erosion levels tend to increase one level in sub-section areas in the coming years. Originality/value: This study assesses forest and erosion status in Kien Giang and Ca Mau provinces, Vietnam, providing local insights into environmental challenges. It uses a rigorous methodology, analyzes erosion levels, and classifies the area into sub-sections. The study also highlights the potential impact of climate change on erosion, promoting proactive adaptation and mitigation efforts.

Formation and significance of topologically close-packed Laves phases in refractory high-entropy alloys

Refractory high-entropy alloys (RHEAs) inherently have a high potential to form topologically close-packed (TCP) Laves phases. Phase engineering to control the amount and type of TCP-Laves phases plays an important role in physical and mechanical properties of RHEAs. The present investigation addressed key parameters to TCP-Laves phase formation in RHEAs by considering thermodynamic calculations and empirical relations. Two novel TiVCrZrCo and TiVCrZrFe RHEAs were designed and fabricated as alloy models with high melting points (>2000 K) and relatively low density (∼6.5 g.cm−3) with multiphase microstructure including BCC matrix together with C14 and C15 Laves phases. Existence of atoms such as V, Co, Cr and Fe together with Zr, Ti, Nb and Hf refractory elements promote TCP-Laves phase formation. Very negative values for mixing enthalpy of atom pairs (ΔHmix) and remarkable differences between atomic sizes of the constitutive elements (δ) are key factors in the Laves phase formation in multicomponent alloys. The parameters including ΔHmix and δ must be in the defined range of −20 ≤ ΔHmix ≤ −3 kJ.mol−1 and 4 <δ < 10 to appear Laves phase in the microstructures of HEAs. TCP-Laves phase formation led to increase and decrease in hardness and fracture toughness, respectively. The understanding of key factors in RHEAs design can lead to phase engineering and the fabrication alloys with a desirable amount of TCP-Laves phase, which are suited for hydrogen storage applications or for applications in harsh operating environments exposed to high temperatures, irradiations, wear and erosion.

Annual and Seasonal Characteristics of Rainfall Erosivity in the Eastern Rhodopes (Bulgaria)

Rainfall, with its intensity, duration, and seasonal distribution, is among the main factors causing soil erosion, which is a widespread environmental problem in Bulgaria. Rainfall erosivity shows the potential of precipitation to generate erosion processes and is an essential indicator of the climate vulnerability of a region. This paper aims to evaluate rainfall erosivity in a part of the Eastern Rhodopes Mountains, an area that is characterised by high-intensity erosion processes and high erosion risk. Local peculiarities of rainfall erosivity were revealed by the calculation of some precipitation indices based on the monthly precipitation for the period 2000–2021, such as the precipitation concentration index (PCI), Angot precipitation index, Fournier index (FI), and modified Fournier index (MFI). The analysis of the extremely wet and extremely dry months at the annual and seasonal (October–March and April–September) levels was performed to evaluate the susceptibility to erosion. The results from the study show that rainfall erosivity in the studied area varies from low to moderate in the northern part of the study area and from high to very high in the south. According to the MFI, high and very high erosivities have been observed mainly since 2012. The erosivity increases from north to south, to the area with a complex relief, where the combination of orography and atmospheric circulation make favourable conditions for the occurrence of extreme precipitation. The analyses of the calculated indices show that the precipitations in most of the studied area generally have from a low to a moderate erosivity, but this does not exclude the occurrence of cases with high and very high erosivities, which are characteristic of recent years and are related to the increase in annual precipitations and extreme precipitation months. The results of this study can contribute to the development and implementation of measures and preventive activities for the reduction and possible elimination of the negative impacts of extreme precipitation.

Quantifying Soil Erosion in Drought-Impacted Central Odisha, India, through Geospatial Mapping with RUSLE

Soil degradation in Odisha poses a significant conservation concern for the local environment. The present research focused on a region in central Odisha State, India, affected by drought conditions. Several models have emerged to assess soil loss, with the Revised Universal Soil Loss Equation (RUSLE) standing out as the most suitable option. The erosion computation process entails utilizing the digital elevation model (DEM), Landsat-9 imagery, and soil data from several sources accessible in different forms and scales. The present analysis took into account various elements, namely, crop management factor (C), practice management factor (P), slope length factor (LS), steepness factor of the slope (S), and rainfall factor (R). Multiplying these factors yielded the average rate of soil erosion. Areas with a high slope length factor, such as those in Kandhamal, Kalahandi, and Nuapada, have a high erosion rate. The study reveals that 57% of the land in the study area experiences very low to moderate soil erosion at a rate of 2–10 tons per hectare per year, while 43% faces moderately to very severe erosion at a rate of 10–25 tons per hectare per year. Erosion hotspots, covering 32,205 square kilometers, are mainly identified in agricultural and forested hilly areas where slopes exceed 10°, such as those in Kandhamal, Kalahandi, and Nuapada, which have a high erosion rate. These districts are especially vulnerable to soil loss and resulting climate action (Sustainable Development Goals-13) because of frequent and severe rainfall, shifting agricultural practices, a thin surface soil covering, natural erosion, and barren hills. The research emphasizes the urgent need for implementing conservation and management measures to protect high-risk areas from further degradation. In conclusion, the study underscores the effectiveness of the RUSLE-GIS model in conducting quantitative and spatial assessments of soil erosion on a river watershed scale. The model is deemed crucial in formulating conservation strategies to address the identified erosion issues in the tropical highlands of the area.

Applicability Comparison of GIS-Based RUSLE and SEMMA for Risk Assessment of Soil Erosion in Wildfire Watersheds

The second-largest wildfire in the history of South Korea occurred in 2022 due to strong winds and dry climates. Quantitative evaluation of soil erosion is necessary to prevent subsequent sediment disasters in the wildfire areas. The erosion rates in two watersheds affected by the wildfires were assessed using the revised universal soil loss equation (RUSLE), a globally popular model, and the soil erosion model for mountain areas (SEMMA) developed in South Korea. The GIS-based models required the integration of maps of the erosivity factor, erodibility factor, length and slope factors, and cover and practice factors. The rainfall erosivity factor considering the 50-year and 80-year probability of rainfall increased from coastal to mountainous areas. For the LS factors, the traditional version (TV) was initially used, and the flow accumulation version (FAV) was additionally considered. The cover factor of the RUSLE and the vegetation index of the SEMMA were calculated using the normalized difference vegetation index (NDVI) extracted from Sentinel-2 images acquired before and after the wildfire. After one year following the wildfire, the NDVI increased compared to during the year of the wildfire. Although the RUSLE considered a low value of the P factor (0.28) for post-fire watersheds, it overestimated the erosion rate by from 3 to 15 times compared to the SEMMA. The erosion risk with the SEMMA simulation decreased with the elapsed time via the vegetation recovery and stabilization of topsoil. While the FAV of RUSLE oversimulated by 1.65~2.31 times compared to the TV, the FAV of SEMMA only increased by 1.03~1.19 times compared to the TV. The heavy rainfall of the 50-year probability due to Typhoon Khanun in 2023 generated rill and gully erosions, landslides, and sediment damage in the post-fire watershed on forest roads for transmission tower construction or logging. Both the RUSLE and SEMMA for the TV and FAV predicted high erosion risks for disturbed hillslopes; however, their accuracy varied in terms of the intensity and extent. According to a comparative analysis of the simulation results of the two models and the actual erosion situations caused by heavy rain, the FAV of SEMMA was found to simulate spatial heterogeneity and a reasonable erosion rate.

Experimental effect of wind and heavy rain on increased splash erosion using rainfall simulator

To investigate the erosion process that occurs, rainfall simulation is used with a model scale for natural rain events in laboratory conditions. The calculation of erosion and any soil erosion with a slope setting of 5% was carried out experimentally on a laboratory scale using a rain simulator and adding wind using a 2-inch snail blower. Experiments carried out in the laboratory included erosion tests driven by rain and erosion tests by rain, which were given additional wind variables. Rain intensity used for testing is using discharge 1 litre/minute,1.5 litre/minute, and 2 litre/minute as a representative variation of rainfall. The occurrence of rain and wind simultaneously within a certain period will cause greater loss of soil. Although many studies have been conducted on the effects of rain and the combined effects of wind on soil erosion, only a limited number of studies have focused on the combination of the two variables that occur together. The results showed that in the applied rain intensity and wind factor, the collision of the kinetic energy of the rain driven by the wind resulted in higher erosion when compared to that without the influence of the wind.

Appraisal of active tectonics in Karangsambung Amphitheater: Insights from DEM-derived geomorphic indices and geological data

The morphology of the Karangsambung area shows a unique form, namely the morphology of the amphitheater. This area results from the complexity of tectonic, erosion, and depositional processes. The active tectonics in this region greatly influence the drainage system and geomorphic expression. The study area provides evidence of subduction in Java. It is an ideal natural laboratory for studying evidence of tectonic activity due to the subduction of the Indo-Australian plate with the Eurasian plate during the Cretaceous period. We evaluated active tectonics using the DEM to assess the characteristics of the geomorphic index. The results obtained from these indices were combined to produce an index of relative active tectonics (IRAT) using GIS. The average of the seven geomorphic indices measured was used to evaluate the distribution of relative tectonic activity in the study area. We defined four classes to determine the relative level of tectonic activity: class 1: very high (1.0 ≤ IRAT < 1.5); class 2: high (1.5 ≥ IRAT < 2); grade 3: moderate (2 ≥ IRAT < 2.5); and grade 4: low (2.5 ≥ IRAT). The results show that the study area was strongly deformed and was influenced by tectonic activity. Landsat imagery, DEM, and field observations also proved the presence of active tectonics in the form of uplift accompanied by high vertical erosion forming pointed hills with narrow valleys, the exposure of Cretaceous-aged rocks, amphitheater morphology, and the uplift of river terraces. The indicative IRAT values were consistent with the relative uplift levels, landforms, and geology.

MENGGALI POTENSI PEMANFAATAN LAHAN MARGINAL MENJADI LAHAN PRODUKTIF DALAM RANGKA MEMPERTAHANKAN KETERSEDIAAN PANGAN DI MASA MENDATANG

&lt;p&gt;&lt;em&gt;&lt;span lang="EN-US"&gt;Marginal land is a critical land that is less promising. This study aims to identify and analyze the potential of marginal land to anticipate future food availability and to review the constraints faced by marginal land. The methods used is literature study and comparative study. A literature study was conducted to obtain a theoretical basis on the standard of agricultural research centers on marginal lands, while a comparative study was conducted to obtain an overview of agricultural research on marginal lands in Indonesia. The results showed that marginal land had various cultivation potentials such as rice, corn, oil palm, sweet potatoes, and peanuts. The potential of the livestock sector and the tourism sector can also be a potential choice for exploiting the potential of marginal land. The potential for marginal land in the future is expected to be used as a more productive land as an alternative in preparing food availability in the future. So that food and ecosystem stability is maintained. Socio-economic aspects that are considered in the management of marginal land include agro-economy, production, marketing, and institutions. Meanwhile, the constraints on the utilization of marginal land are, among others, prone to high erosion rates, low fertility levels, limited capital, limited facilities and infrastructure, and high rates of crop failure.&lt;/span&gt;&lt;/em&gt;&lt;/p&gt;

Spatiotemporal dynamic of soil erosion and the key factors impact processes over semi-arid catchments in Southwest China

The heterogeneity of geographic environments and vegetation types plays a crucial role in determining soil erosion patterns. Highlighting the influence of environmental factors and their gradient changes on soil erosion is key to effective control and management. In this study, conducted in the arid-hot valley area of the Jinsha River, one of the main sand-producing areas in the Yangtze River Basin, we considered the topographic factors and land cover and applied the Revised Universal Soil Loss Equation (RULSE) with geographic information system (GIS) was applied to quantify the contribution and change pattern of different factors to soil erosion in the arid-hot valleys. Then, the spatial and temporal patterns of soil erosion in 2000 and 2015 were analyzed, showing erosion amount of 1812.96 t/(km2·a) and 1965.98 t/(km2·a), respectively. The increase in erosion was attributed to the frequency of heavy rainfall events. In terms of spatial distribution, strong soil erosion has been mainly observed in arid-hot basins, such as Yuanmou and Huaping. The soil erosion modulus (SEM) was closely connected to topographical elements, increasing incrementally with slope. High soil erosion areas were predominantly distributed across slopes between 18° and 36°. In contrast, SEM decreased gradually with increasing altitude, with strong erosion occurring primarily below 2000 m. SEM for different land use types followed this order: bare land > cultivated land > grassland > forest > paddy land. Based on the relationship between vegetation cover and soil erosion, the area could be roughly divided into three types of area by vegetation coverage: erosion control areas (30% vegetation coverage), erosion-vegetation transition areas (30–70%), and vegetation control areas (>70%). These results provide an essential reference for assessing soil erosion patterns and implementation of ecological vegetation restoration measures in arid-hot valleys.

Identifying geomorphic domains using hierarchically clustered drainage area‐slope scaling

AbstractArea‐slope scaling is an important tool for analysing geomorphic processes. In this study, we used hierarchical clustering to sort the area‐slope scaling data for both the numerical landscape created using the LandLab model and real landscapes. Random forest analysis was used to explore the effect of hierarchical clustering. We aimed to illustrate the heterogeneous features of area‐slope clustering and their influencing factors and to test whether they can be used to distinguish geomorphic domains. Our results showed that hierarchical clustering can easily detect the heterogeneous features of area‐slope scaling constrained by tectonic uplift and fluvial erodibility but not those constrained by the diffusion coefficient. The slope gradients over the inflection/transition zone of the colluvial and fluvial domains play a key role in identifying area‐slope scaling from different geomorphic domains. Case studies show that area‐slope scaling of clusters would be affected by different lithology and distance away from the trunk channel. In the high erosion circumstance, the fluvial process caused by tectonics leads to increasing slope gradients over whole geomorphic domains, as well as to retreating inflection between the colluvial and fluvial process domains. In low erosion circumstances or steady state, the fluvial process caused by nearby rivers cannot effectively change the slope gradients but can retreat the inflection. The real landscapes suggest that basins should be carefully selected for area‐slope scaling analysis to ensure that they are representative of the entire study area. Before geomorphological research, more basins of a specific research region need to be selected to conduct hierarchical clustering to select representative basins. Our study could be helpful in the identification of area‐slope domains, the extraction of geomorphic metrics and geomorphic process research.

Effect of climate change on soil erosion rate in a tropical Indian catchment

Abstract This study analyzes the variations in soil erosion rate in a tropical catchment in India using the empirical Revised Universal Soil Loss Equation (RUSLE) model integrated with climate change scenarios from an ensemble of global climate models (GCMs) included in the NEX Global Daily Downscaled Projections Coupled Model Intercomparison Project Phase 6 dataset for Shared Socioeconomic Pathways (SSP) 126 and SSP 585. A set of seven GCMs are initially selected. Based on their ability to simulate the rainfall for the current scenario, the PROMETHEE-II method is used to rank the GCMs and the top four best-performing models are used for further analysis. Soil erosion rates projected for the future climate scenarios are compared with the current scenario. In the near future and in the middle of the century, soil erosion rates under the SSP 126 scenario are projected to be higher than that under the SSP 585 scenario. The ensemble average soil erosion rate is projected to increase by 15.41%–25.94% toward the end of the century for different emission scenarios, and the areas susceptible to high and very high soil erosion rates are projected to increase to 40.3%.

Strontium isotope proxy of sedimentological records reveals uplift and erosion in the Southeastern Neo-Tethys ocean during the late Cretaceous

The mutual interplays between plate tectonic processes, orogenesis and continental uplift, high-flux magmatism, and high sedimentation rates can affect the geochemical signatures and composition of marine sediments. Here, we examine two major disconformities, the Cenomanian–Turonian boundary (CT-ES) and the middle Turonian (mT-ES) exposure surfaces, from the Upper Cretaceous sedimentary successions of the southeastern Neo-Tethys Ocean in the Zagros Basin (Iran). The disconformities are expressed as distinct positive peaks in rubidium (Rb) contents and 87Sr/86Sr isotopic ratios of carbonates. The 87Sr/86Sr values of samples bracketing the disconformities in seven well cores give average age ranges of 94.4–93.6 Ma for the CT-ES and 91–86 Ma for the mT-ES. These ages fall in the timespan of forearc/ophiolite formation through subduction initiation in the Neo-Tethys realm (southern margin of Eurasia), high convergence velocities between Arabia and Eurasia, and blueschist exhumation. All these processes involved buckling of the Neo-Tethyan lithosphere, initiating the Neo-Tethys closure and a high erosion rate on the Eurasian margin. The first two mechanisms exerted considerable compressional forces on the adjacent carbonate platforms, reactivated basement faults, and led to the uplift and erosion of the Arabian Plate, which provided the high contents of Rb and the high 87Sr/86Sr ratios in the carbonates.

Evaluating the Environmental Quality of Forest Remnants Using Landscape Metrics

Forest remnants are hotspots of biodiversity and play an important role in providing services such as regulating the climate, reducing surface runoff, helping erosion control, protecting and contributing to the balance of ecosystems, and other functions. Despite this, natural vegetation is fragmented and limited to a few remnants, which are gradually suffering from anthropogenic pressures. Assessing the environmental quality of these remnants is therefore vital to understanding their current condition and to provide support for their conservation. This study aims to assess the environmental quality of forest remnants in six water basins in the municipality of Campinas/SP, Brazil. Forest remnants were mapped, and their environmental quality was assessed by applying an analytic hierarchy process (AHP), considering a set of structural landscape metrics previously selected from the literature. Of the 2319 forest remnants evaluated, 4.5% and 30%, respectively, registered high and low environmental quality. The Atibaia and Jaguari basins recorded the highest number of environmentally fragile remnants due to their small size and being predominantly elongated, and to the high erodibility of the soil. In the Anhumas, Capivari, Capivari-Mirim, and Quilombo basins, medium-sized forest remnants predominate. There is a greater distance between them, with a high intensity of land use/land cover in their surroundings, related to the prevalence of urbanized areas. Specific management actions should be taken in each of these basins.