Dimitar Zhelev, Kliment Naydenov, Eugenia Sarafova
et al.
Climate change raises pressing questions regarding the environmental impact of food systems. Carbon footprinting could serve as a potential measure to guide climate-friendly food consumption in Bulgaria. This study explores the opportunities and challenges of using carbon footprinting to guide consumer behaviour and promote sustainable consumption. The study, based on a detailed analysis of policy guidelines, international standards (GHG Protocol, ISO 14067, LCA), and national socio-economic conditions, assesses the capacity of the Bulgarian food sector to implement transparent climate reporting. The results show that while European policies such as the Green Deal and the Farm to Fork Strategy provide a helpful context, Bulgaria struggles with limited consumer knowledge, insufficient data infrastructure, and financial constraints for SMEs. Consumer interest in sustainability, especially among young people, is growing. However, behavioural inertia, price sensitivity, and lack of knowledge about eco-labels are hindering widespread adoption. The study concludes that carbon footprint labelling in Bulgaria has great potential to promote climate responsibility. However, this can only be achieved through coordinated political support, public awareness campaigns, technological integration, and culturally sensitive communication. Incorporating carbon footprint labelling into national sustainability policies can trigger a broader shift towards climate-friendly diets and help align public behaviour with long-term environmental goals.
Paulo Roberto Bairros da Silva, Márcia Luciane Kochem, Jean P.G. Minella
et al.
The high average load of suspended sediments in rivers in southern Brazil is related to soil degradation in agricultural areas due to erosive processes resulting from inadequate management. In this context, understanding the dimensions of transported particles and their biogeochemical dynamics is essential, as well as their transport capacity, load, concentration, deposition potential, and degradation within the fluvial system. This study analyzed hydrological characteristics, particle size, and chemical properties (TOC, NT, PT, POrg, Pd) in three river basins in Rio Grande do Sul (2012-2013): Arroio Lajeado Ferreira (1.19 km²), Rio Guaporé (1,980 km²), and Rio Conceição (804 km²), all located in southern Brazil. This research revealed that erosion during heavy rainfall in southern Brazil acts as a selective "geochemical erosion" process, preferentially transporting fine sediments (<63 µm) enriched with nutrients. The dynamics of phosphorus, during intense rainfall events can become predominantly organic (>50%), and quantifying significant loads of bioavailable phosphorus and organic carbon to rivers. The Conceição River Basin stood out with the greatest nutrient loss per area, demonstrating that agricultural practices exacerbate this impact. Suspended sediments (< 63 µm) showed high concentrations of organic carbon, nitrogen, and phosphorus (especially Pd, which is of environmental concern). The particle size D(25), D(50), D(75) did not vary significantly between basins or rainfall events. Phosphorus exhibited a dynamic behavior, at basal flow, it was predominantly inorganic, but during rainfall events, more than 50% could be organic.
Séverine Chevalier, Olivier Beauchard, Adrian Teacă
et al.
Abstract Benthic ecological data are crucial to study and manage ecosystems. On the one hand, abiotic and species data provide complementary information to identify habitats. On the other hand, trait data, describing taxon characteristics, are required to predict anthropogenic impacts on marine ecosystems. Indeed, species traits are now widely used to understand natural selection in communities or to highlight ecosystem functions. While trait data are in growing demand, compiling them is challenging, time-consuming and there are no properly established procedures for major marine ecosystems. Here, we share a data set comprising macrozoobenthic occurrences for 215 taxa over the Black Sea northwestern shelf, between 1995 and 2017, and 27 traits documented for 127 taxa that related to life cycle and ecosystem function. In addition, we provide an abiotic data set of physical and chemical variables generated by a model or compiled from in-situ data. This data set aims to fill the functional knowledge gap in the Black Sea and offers research opportunities to future studies covering ecosystem functions, biodiversity conservation, and management.
CHEN Ziquan 1 , HE Chuan 1, YU Bingxin 1, LI Zheng 1, 2, ZHANG Hang 2, LIU Maoyi 2
The long-term structural safety issues of water-rich tunnels under complex hydrogeological conditions during operation period and their mutual interaction mechanism with groundwater environment are receiving increasing attention. To study the evolution process of seepage and stress field of urban tunnels with small interval and propose reasonable waterproof-drainage methods, the model tests and numerical studies on seepage are carried out based on the Kexuecheng Tunnel in Chongqing City. The evolution process of water and earth pressure on the lining structures is revealed. Subsequently, a proactive control technology for groundwater environmental protection based on the collaborative regulation of drainage and structural safety is proposed. The results indicate that the precipitation funnels formed by the left and right holes of urba tunnels with a small interval partially overlap and affect each other in space. The water pressure exhibits a W-shaped distribution in the horizontal direction, gradually evolving into a concave arc shape as the burial depth increases or decreases. The horizontal influence range of the seepage field and stress field exceeds 80 meters. The reduction effects of grouting circle on water pressure and surrounding rock pressure decrease with the increase of water head height. When the water head height is 30~50 m, the reduction ratio of grouting circle to the total load is about 18.6%~40%. The distribution of earth and water pressure of tunnels with small interval shows significant asymmetry. Under heavy rainfall conditions, the evolution process of the total load on the lining can be divided into three stages: slow growth, rapid growth and gradual stability phase. The secondary lining cracking and water inrush disasters caused by high water pressure are mainly concentrated at the haunch, arch foot and bottom of tunnel. For high water pressure sections of urban tunnels with small interval, it is recommended to add drainage blind pipes at the inverted arch. In ecologically sensitive areas, the active regulation technology should be adopted for groundwater discharge in tunnels to protect the ecological balance of groundwater environment.
Engineering geology. Rock mechanics. Soil mechanics. Underground construction
Alex T. Ford, Amruthavarshini Shankar, Sarah Reynolds
et al.
Abstract The planet faces a triple crisis from climate change, biodiversity loss, and pollution. Like any country, the UK needs to attract the best available talent to become thought leaders to overcome these global challenges. Several Science, Technology, Engineering and Maths subjects in the UK face challenges with attracting ethnic minority students. As part of a wider project on diversity in UK environmental/marine science, we analysed university applications amongst 180 environmental and 88 marine science degrees in the UK between 2019–2021. We found them to be the least diverse degree subjects for ethnic minority students and Asian students were less likely to be accepted than white students on environmental science degrees. A survey of UK marine science course leaders highlights the belief that these issues impact the pipeline of diversity from higher education institutions to marine/environmental science careers. In this paper, we discuss the impacts of these findings and develop a roadmap to change.
<p>African and South American (ASA) wildfires account for more than 70 % of
global burned areas and have strong connection to local climate for
sub-seasonal to seasonal wildfire dynamics. However, representation of the
wildfire–climate relationship remains challenging due to spatiotemporally
heterogenous responses of wildfires to climate variability and human
influences. Here, we developed an interpretable machine learning (ML) fire
model (AttentionFire_v1.0) to resolve the complex controls of
climate and human activities on burned areas and to better predict burned
areas over ASA regions. Our ML fire model substantially improved
predictability of burned areas for both spatial and temporal dynamics
compared with five commonly used machine learning models. More importantly,
the model revealed strong time-lagged control from climate wetness on the
burned areas. The model also predicted that, under a high-emission future climate scenario, the recently observed declines in burned area will reverse
in South America in the near future due to climate changes. Our study
provides a reliable and interpretable fire model and highlights the importance
of lagged wildfire–climate relationships in historical and future
predictions.</p>
<p>In recent decades, multiple researchers have produced landslide susceptibility maps using different techniques and models, including the
information value method, which is a statistical model that is widely
applied to various coastal environments. This study aimed to evaluate
susceptibility to landslides in the Essaouira coastal area using bivariate
statistical methods. In this study, 588 distinct landslides were identified, inventoried, and mapped. Landslides are performed by
means of observation and interpretation of different data sources, namely high-resolution satellite images, aerial photographs, topographic maps, and extensive field surveys. The rocky coastal system of Essaouira is located in the middle of the Atlantic coast of Morocco. The study area was split into 1534 cliff terrain units that were 50 m in width. For training and validation purposes, the landslide inventory was divided into two independent groups: 70 % for training and 30 % for validation. Twenty-two layers of landslide conditioning factors were prepared – namely, elevation, slope angle, slope aspect, plan curvature, profile curvature, cliff height, topographic wetness index, topographic position index, slope over area ratio, solar radiation, presence of faulting, lithological units, toe lithology, presence and type of cliff toe protection, layer tilt, rainfall, streams, land-use patterns, normalised difference vegetation index, lithological material grain size, and presence of springs. The statistical relationship between the conditioning factors and the different landslide types was calculated using the bivariate information value method in a pixel-based model and in the elementary terrain units-based model. Coastal landside susceptibility maps were validated using landslide training group partitions. The receiver operating characteristic curve and area under the curve were used to assess the accuracy and prediction capacity of the different coastal landslide susceptibility models. Two methodologies, considering a pixel-based approach and using coastal terrain units, were adopted to evaluate coastal landslide susceptibility. The results allowed for the classification of 38 % of the rocky coast subsystem as having high susceptibility to landslides, which were mostly located in the southern part of the Essaouira coastal area. These susceptibility maps will be useful for future planned development activities as well as for environmental protection.</p>
Fractures are widely distributed in coal, and studying the seepage characteristics of fluids in fractures is of great significance for unconventional natural gas extraction and prevention of gas disasters. In this work, based on the W-M fractal function, a Y-shaped fracture model with different roughness is established. The seepage characteristics of Y-shaped fracture with different roughness are interpreted from two perspectives. Firstly, the seepage law of the Y-shaped fracture with the same roughness is studied. Secondly, the fluid competitive diversion capacity caused by the difference of branch fracture roughness is discussed. The results show that the fracture roughness is an important factor affecting the seepage characteristics of the fracture. When the roughness of the fracture is identical, the outlet flow rate, velocity, and Re are all positively correlated with pressure, and the flow regime is unchanged. The increase in the fracture roughness will lead to a significant flow rate and momentum loss, resulting in maximum loss up to 45.44%, besides, enhance the flow resistance of the fracture, Re increasing by 771, 713, 489, and 355, respectively, at four patterns. And there is a threshold DM between 1.1 and 1.2 so that the major influencing factor on hydraulic conductivity changes. In addition, the roughness difference between the branch fractures of the Y-shaped fracture is the key factor to control the fluid competitive diversion capacity. The larger the roughness difference, the greater difference in flow velocity, and the more significant change in flow rate proportion, which proportion differs by 4%, 44%, and 54%, respectively, and the stronger smooth branch fracture competitive diversion capacity, and the lower the rough branch fracture hydraulic conductivity. As the inlet pressure increases, the two branch fractures Re gradually increases but Eu decreases, which Eu in smooth branch fracture is smaller is 15, 19, 20, and 21 smaller than that of rough branch, respectively, and the rough branch fracture competitive diversion capacity is weakened. Both roughness difference and inlet pressure will affect the competitive diversion capacity of the Y-shaped fracture. These results are expected to provide new insights for the exploitation of underground fluid resources.
L. J. A. Gerringa, M. Gledhill, I. Ardiningsih
et al.
<p>Competitive ligand exchange–adsorptive cathodic
stripping voltammetry (CLE-AdCSV) is used to determine the conditional
concentration ([<span class="inline-formula"><i>L</i></span>]) and the conditional binding strength (log<span class="inline-formula"><i>K</i><sup>cond</sup></span>) of
dissolved organic Fe-binding ligands, which together influence the
solubility of Fe in seawater. Electrochemical applications of Fe speciation
measurements vary predominantly in the choice of the added competing ligand.
Although different applications show the same trends, [<span class="inline-formula"><i>L</i></span>] and log<span class="inline-formula"><i>K</i><sup>cond</sup></span>
differ between the applications. In this study, binding of two added ligands
in three different common applications to three known types of natural
binding ligands is compared. The applications are (1) salicylaldoxime (SA)
at 25 <span class="inline-formula">µ</span>M (SA25) and short waiting time, (2) SA at 5 <span class="inline-formula">µ</span>M (SA5), and
(3) 2-(2-thiazolylazo)-<span class="inline-formula"><i>ρ</i></span>-cresol (TAC) at 10 <span class="inline-formula">µ</span>M, the latter two
with overnight equilibration. The three applications were calibrated under
the same conditions, although having different pH values, resulting in the
detection window centers (<span class="inline-formula"><i>D</i></span>) DTAC <span class="inline-formula">></span> DSA25 <span class="inline-formula">≥</span> SA5 (as log<span class="inline-formula"><i>D</i></span>
values with respect to Fe<span class="inline-formula"><sup>3+</sup></span>: 12.3 <span class="inline-formula">></span> 11.2 <span class="inline-formula">≥</span> 11).</p>
<p>For the model ligands, there is no common trend in the results of
log<span class="inline-formula"><i>K</i><sup>cond</sup></span>. The values have a considerable spread, which indicates that
the error in log<span class="inline-formula"><i>K</i><sup>cond</sup></span> is large. The ligand concentrations of the nonhumic model ligands are overestimated by SA25, which we attribute to the lack
of equilibrium between Fe-SA species in the SA25 application. The
application TAC more often underestimated the ligand concentrations and the
application SA5 over- and underestimated the ligand concentration. The
extent of overestimation and underestimation differed per model ligand, and
the three applications showed the same trend between the nonhumic model
ligands, especially for SA5 and SA25. The estimated ligand concentrations for
the humic and fulvic acids differed approximately 2-fold between TAC and SA5
and another factor of 2 between SA5 and SA25.</p>
<p>The use of SA above 5 <span class="inline-formula">µ</span>M suffers from the formation of the species
Fe(SA)<span class="inline-formula"><i>x</i></span> (<span class="inline-formula"><i>x</i>>1</span>) that is not electro-active as already suggested by
Abualhaija and van den Berg (2014). Moreover, we found that the reaction
between the electro-active and non-electro-active species is probably
irreversible. This undermines the assumption of the CLE principle, causes
overestimation of [<span class="inline-formula"><i>L</i></span>] and could result in a false distinction into more than
one ligand group.</p>
<p>For future electrochemical work it is recommended to take the above
limitations of the applications into account. Overall, the uncertainties
arising from the CLE-AdCSV approach mean we need to search for new ways to
determine the organic complexation of Fe in seawater.</p>
In deep tunnels with hydro-geological conditions, it is paramount to investigate the geological structure of the region before excavating a tunnel; otherwise, unanticipated accidents may cause serious damage and delay the project. The purpose of this study is to investigate the geological properties ahead of a tunnel face using electrical resistivity tomography (ERT) and tunnel seismic prediction (TSP) methods. During construction of the Nosoud Tunnel located in western Iran, ERT and TSP 303 methods were employed to predict geological conditions ahead of the tunnel face. In this article, the results of applying these methods are discussed. In this case, we have compared the results of the ERT method with those of the TSP 303 method. This work utilizes seismic methods and electrical tomography as two geophysical techniques are able to detect rock properties ahead of a tunnel face. This study shows that although the results of these two methods are in good agreement with each other, the results of TSP 303 are more accurate and higher quality. Also, we believe that using another geophysical method, in addition to TSP 303, could be helpful in making decisions in support of excavation, especially in complicated geological conditions.
BACKGROUND Polycyclic aromatic hydrocarbons (PAHs) are one of the persistent organic pollutants which are carcinogenic and difficult to degrade, and are widespread in the environment. The direct analysis of trace PAHs in the environment is often difficult because of the low sensitivity of the detection methods. It is necessary to combine separation and enrichment methods. Conventional sample pretreatment techniques, such as Soxhlet extraction and liquid-liquid extraction, are time-consuming and use a large number of organic solvents. OBJECTIVES To develop a new, simple, and environmentally-friendly method for sample pretreatment. METHODS Solid phase microextraction (SPME) is a solvent-free pretreatment technology which integrates sampling, enrichment and injection. Combined with gas chromatography-mass spectrometry (GC-MS), it can produce the rapid enrichment and detection of trace organic compounds in a complex matrix. At present, the research focus of improving SPME technology is to improve the mechanical strength and extraction performance of the coating. Using iron wire (IW) as the carrier, which also provided the iron ion source, a porous MOFs film[MIL-53(Fe)] was grown on iron wire with good mechanical stability by in-situ self-transformation. It was used as the solid phase microextraction coating[IW@MIL-53(Fe)]. Seven kinds of non-volatile condensed ring PAHs were used as the target analyte, and immersion extraction mode combined with GC-MS as detection means were used to verify its extraction performance. RESULTS Results showed that the extraction performance of the new coating was 1-2 times higher than that of the commercial 100μm PDMS coating, and the coating can be used stably for more than 120 times. The detection limits of the methods were 0.03-2.25ng/L, the linear ranges were 250-10000ng/L, and the correlation coefficients were in the range of 0.9903-0.9991. The coating was applied successfully to the detection of PAHs in natural water, where the recoveries were from 80.1% to 108.5%. CONCLUSIONS This study not only provides an idea for the simple and rapid preparation of high-efficiency SPME coatings, but also has great potential to be applied to determinate trace volatile organic pollutants in water with high accurateness and efficiency.
Crustal seismic reflection profiling has revealed the presence of extensive, coherent reflections with anomalously high amplitudes in the crystalline crust at a number of locations around the world. In areas of active tectonic activity, these seismic “bright spots” have often been interpreted as fluid magma at depth. The focus in this report is high-amplitude reflections that have been identified or inferred to mark interfaces between solid mafic intrusions and felsic to intermediate country rock. These “frozen sills” most commonly appear as thin, subhorizontal sheets at middle to upper crustal depths, several of which can be traced for tens to hundreds of kilometers. Their frequency among seismic profiles suggest that they may be more common than widely realized. These intrusions constrain crustal rheology at the time of their emplacement, represent a significant mode of transfer of mantle material and heat into the crust, and some may constitute fingerprints of distant mantle plumes. These sills may have played important roles in overlying basin evolution and ore deposition.
For many years, groundwater was the main water resource in Israel. Relying for years on the storage of the aquifers dropped their water level close to their red lines and exposed the aquifers to salinization hazards. Climate change effect is expected to lead to additional reduction of about 2% per year in the rainfall leading to long term reduction in the aquifers recharge. Those conditions brought the Government of Israel to produce desalinated seawater as a new artificially water resources reducing the groundwater pumping and rehabilitating the aquifers storage. During low demand periods there is a surplus of high-quality desalinated seawater for hours or days that can be temporary injected and stored in the aquifers and later pumped during high demand period. Basically, artificial recharge is done in many ways and techniques. The most common ways are injection in infiltration ponds or through injection wells. This paper is focused on activities that were done in injection wells. The main outcome from the pilots was that the new design and construction of the injection wells reduced dramatically the well loss and improved the specific capacity (hourly discharge versus the dynamic drawdown) during the injection. Proper Managed Aquifer Recharge (MAR) should combine infiltration ponds with injection wells for injecting the surplus water together with batteries of pumping wells for pumping the injected water in short time during high demand periods.
Slope excavation rate has an important influence on slope stability.It is of great significance to study the deformation and failure characteristics of locked high-steep rock slope under different excavation unloading rates and the failure mechanism of internal rock bridge. In order to simulate creep failure in front and tension cracks in back edge of landslide, a middle rock bridge is formed at the end of complete rock sample by prefabricating cracks, three kinds of biaxial unilateral unloading tests with different length of rock bridge are carried out, the strength, deformation, failure characteristics and crack propagation modes of three rock bridge length specimens under different unloading rates are analyzed, the evolution process and mechanical mechanism of fracture propagation are discussed. The results show that:① The unloading rate mainly affects the unloading strength and the number of secondary cracks, but has little effect on the crack propagation mode.② The stress-displacement curve shows the phenomenon of "steep drop of stress" and "recovery after peak", and the specimen also shows the characteristic of "multi-peak".③ With the increase of unloading rate, the failure mode of specimen gradually changes from shear failure to tensile failure, and most of the tensile cracks are concentrated near the unloading surface.④ Six types of fracture propagation are generalized:the coalescence rock bridge, the coalescence specimens upper end face, lower end face of lower crack coalescence specimens, upper end face of lower crack coalescence specimens, the coalescence specimen's left end face, the coalescence specimen's right end face. ⑤ The expression of SIF at the tip of closed crack under unloading is derived, the error of fracture initiation angle obtained by theoretical calculation and experiment is kept within 6.5%, which verifies the feasibility and rationality of the theoretical calculation results.
Karst-derived breccia is the most analysed deposit in fossil-bearing Southeast Asian caves due to its superior preservation potential for human, faunal, archaeological, and palaeontological data. The study of breccia can provide a better understanding of human and faunal histories, and an opportunity to investigate site taphonomy and insights into environments of deposition and post-depositional processes. We review the literature on approaches used to improve the taphonomic understanding of cave deposits in Southeast Asia and how these deposits fit into a cave’s life history. We discuss common methods used to extract taphonomic data retained in Southeast Asian cave deposits and the associated opportunities to discern the mechanisms of cave formation, depositional history, and faunal accumulation. While attempts have previously been made to discern the taphonomic characteristics of Pleistocene vertebrate remains in the region, there has been no comprehensive review outlining methods used to understand taphonomic histories and the biases introduced through these processes. We illustrate the challenges of researching cave breccias in Southeast Asia and the knowledge gaps brought about by conventional methodologies. Uncertainties exist about the extent to which breccia can be examined to infer the taphonomic history of a vertebrate assemblage. These uncertainties exist in part because of dating complexities. This review demonstrates that a taphonomic analysis of breccia in complex long-term accumulations requires a multi-disciplinary approach. We recommend using digital techniques to record spatial distribution data for a thorough interpretation of taphonomic characteristics.
Accurate prediction of the flow rate of horizontal gas well is necessary for economic feasibility, planning and development of gas field. Most of the early models assumed that the production from the horizontal well is infinitely conductive except few recent models. Some recent models reported in the literature for estimating flow rate in horizontal well where the pressure losses due to friction along horizontal drain hole was considered.An improved model that checks the impact of all possible well bore pressure losses on gas production rate of horizontal well is reported. The neglected impact of well bore pressure losses due to fluid accumulation and kinetic energy in the past models is thought to be a conceivable reason for the inconsistency between computed rates from the models and rates got from production tests. The new model was validated using the same field contextual investigation utilized by Guo et al. and outcome got from the new model yields more satisfactory results. A more realistic results that evident all flow phenomena in gas well include the initial unsteady, pseudo-steady and steady state flow condition hence flow rate at any given production time has been established for flow of gas along horizontal well. The outcomes of the study demonstrate that the percentage deviation of the new model at steady state flow condition is less than 5.0% compared with 11.05% acquired from Guo et al. model following by 259.7% from Furui's model, and 1118.2% got from Joshi's model. This work gives field operators a precise and helpful device for prediction and assessment of production in a gas horizontal well. Keywords: Flow rate, Horizontal well, Unsteadiness, Steadiness, Well bore pressure losses
Petroleum refining. Petroleum products, Engineering geology. Rock mechanics. Soil mechanics. Underground construction
Abstract The recovery factor from tight gas reservoirs is typically less than 15%, even with multistage hydraulic fracturing stimulation. Such low recovery is exacerbated in tight gas condensate reservoirs, where the depletion of gas leaves the valuable condensate behind. In this paper, three enhanced gas recovery (EGR) methods including produced gas injection, CO2 injection and water injection are investigated to increase the well productivity for a tight gas condensate reservoir in the Montney Formation, Canada. The production performance of the three EGR methods is compared and their economic feasibility is evaluated. Sensitivity analysis of the key factors such as primary production duration, bottom-hole pressures, and fracture conductivity is conducted and their effects on the well production performance are analyzed. Results show that, compared with the simple depletion method, both the cumulative gas and condensate production increase with fluids injected. Produced gas injection leads to both a higher gas and condensate production compared with those of the CO2 injection, while waterflooding suffers from injection difficulty and the corresponding low sweep efficiency. Meanwhile, the injection cost is lower for the produced gas injection due to the on-site available gas source and minimal transport costs, gaining more economic benefits than the other EGR methods.
Cemeteries and graveyards not only serve as a peaceful place to commemorate the dead. For geologists—whether amateur, student or professional—almost any urban cemetery provides a valuable opportunity to carry out scientific field work at leisure, right on the doorstep, and at no cost. Cemeteries offer an excellent opportunity to examine and study a wide range of stone types in a small space. They also serve as a useful field area for studying rock weathering.