Mediterranean Zone Research Articles

Effective Microorganisms Improve Growth, Nutrients Uptake, Normalized Difference Vegetation Index, Photosystem II, and Essential Oil While Reducing Canopy Temperature in Water-Stressed Salvia sclarea Plants

Clary sage (Salvia sclarea L.), a member of the Lamiaceae family of aromatic plants, is used as a flavoring in the food, fragrance, and cosmetic industries. Egypt’s food and pharmaceutical industries require more natural resources, thus new crops have been introduced to meet the demand. In addition, various environmental conditions, such as water stress, influence aromatic plant growth and essential oil output. The microorganisms included in biofertilizers that have enzymes that solubilize minerals include plant growth-promoting rhizobacteria (PGPRs). Therefore, a field experiment was carried out to test how irrigation management, i.e., 100% of reference evapotranspiration (ETo) (full irrigation) or 50% ETo (water stress), can affect herbal yield, essential oil, and physiological aspects of clary sage, as well as how to improve clary sage plants utilizing biofertilizer in the field in Egypt’s Mediterranean climate zone. The main processes through which PGPRs aid clary sage plants in coping with water stress include increased macro and micronutrient concentrations (P, N, K, Ca, Mg, Zn, B, Mn, Cu, and Fe), dehydrogenase activity, essential oil, and physiological and growth traits of photosystem II (Fv/Fm), chlorophyll content (SPAD-value), plant’s health (normalized difference vegetation index, NDVI), shoot dry weight, and leaf area in clary plants. Application of different PGPRs reduced canopy temperature (CT), thus improving clary sage plants either under 100% ETo or 50% ETo. Consequently, the usage of PGPRs is appropriate for alleviating environmental stresses experienced by clary sage plants and has potential use in maintaining productivity in water stress and may thus be regarded as an important component of sustainable agricultural practices.

A structured framework to interpret hydro-climatic and water quality trends in Mediterranean climate zones

Many regions of the world have experienced rapid hydro-climatic changes in recent decades. Mediterranean areas have especially experienced prolonged droughts, changes to runoff, and low-flow periods. Many methods and assumptions for assessing trends in rainfall and runoff are available, however, a comprehensive framework is required that can consider variations at large temporal and spatial scales, long-term persistence (LTP), seasonal patterns, and multiple change points. An analysis framework has been developed in R and applied to a network of 107 rainfall gauges (with about 100 yrs data) and 90 streamflow-water quality gauges (30 – 50 yrs data) across South-west Western Australia, a region with a typical Mediterranean climate. Trends were estimated using the Original Mann–Kendall (OMK) family of tests including using the Mann-Kendall Test under the Scaling Hypothesis (MKLTP) and Seasonal Mann–Kendall (SMK). Single and multiple change points were calculated by the non-parametric Lanzante’s test (LAT), E-Agglomerative algorithm (ECP), and Energy Divisive (EDP). Trend tests show annual rainfall has decreased by 2.6 mm/yr in the Western areas and increased by 0.9 mm/yr in the Eastern areas with corresponding change points in the 1940 s-1960 s and from 1995 to 2000 although 30 % of the annual rainfall and 100 % of the standardized precipitation index (SPI) time series were found to be under LTP. A regional flow trend analysis shows catchments are yielding much less runoff in more than 90 % of gauged stations. The runoff in perennial and ephemeral streams has shown a decline with the rate of 6 (54 %) and 2 (50 %) mm/yr, respectively. Runoff and baseflow decline occurred as step changes lagged after rainfall, and the rate of decline in baseflow was more than for runoff, suggesting that groundwater connectivity with stream inverts has fallen substantially. Stream salinities increased by 64 mg/L/yr (or 15 %) overall which was highly significant. The framework provides a structured approach to analyse changes in rainfall, runoff and stream salinity for a Mediterranean climate that is projected to become even warmer and drier.

The Age of Evapotranspiration: Lower‐Bound Constraints From Distributed Water Fluxes Across the Continental United States

AbstractUnlike streamflow, which can be sampled in aggregate at the catchment outlet, evapotranspiration (ET) is spatially dispersed, challenging large‐scale age estimation. Here, we introduce an approach for constraining the age of ET via mass balance and present the minimum flux‐weighted age of ET across the continental United States using distributed, publicly available water flux data sets. The lower‐bound constraint on ET age can be calculated by assuming that ET is preferentially sourced from the most recent precipitation through a last‐in, first‐out algorithm. From 2012 to 2017, ET was at least several months old across large areas of the western continental United States, including in Mediterranean and (semi‐)arid climate zones and shrub and evergreen needleleaf plant communities. The primary limitation of this approach is that it provides only a minimum flux‐weighted average age to satisfy the mass balance of outgoing fluxes; true ET fluxes are composed of distributions of ages and may be composed of much older water. The primary advantage of the approach is that flux time series of precipitation and ET are sufficient to constrain ET age, and model parameterization is unnecessary. ET ages can be used to validate tracer‐aided and modeling approaches and inform studies of biogeochemistry, water‐rock interactions, and plant water sourcing under drought.

Differences between provenances in terms of some morphological characteristics in the scotch pine (Pinus sylvestris L.) provenance trial of the Lakes region

This study was carried out to evaluate some morphological features of a Scotch pine (Pinus sylvestris L.) provenance trial, which was established twenty years ago with thirty provenances in Isparta-Aydoğmuş and Burdur-Kemer, located in the Mediterranean climate zone. Within the scope of the research, measurements and observations were made on some morphological characteristics (tree diameter, branch thickness, number of branches, branch angle) in the most successful ten provenances, according to the results of scientific studies carried out from the day the experiment was established until today. When a common evaluation is made in terms of all studied characters, Çatacık, Mesudiye, Şenkaya, Sarıkamış, and Gölköy provenances can be recommended as an alternative seed source for the trial areas and their surroundings.

Revisiting Late Pleistocene-Early Holocene mountain gazelle (Gazella gazella) body size change in the southern Levant: A case for anthropogenic impact.

The average body size of human prey animals in archaeological sites is influenced by myriad environmental, physiological and anthropogenic variables. When combined with supporting evidence, body size has the potential to provide a proxy for several variables of fundamental interest to archaeologists including climatic change, food availability and hunting impacts, among other things. In the southern Levant changes in mountain gazelle (Gazella gazella) body size in the Late Pleistocene were initially interpreted as evidence for a climatic downturn, but the picture has become increasingly murky as data has grown. Here we reconsider trends in gazelle body size using an updated dataset from the Mediterranean zone that spans the Early Epipaleolithic to the Middle Pre-Pottery Neolithic B period (ca. 24,000–9,500 cal BP). Our results reveal that gazelle were smallest in the Early and Middle Epipaleolithic (Kebaran and Geometric Kebaran), reached their largest size in the early Late Epipaleolithic (Early Natufian) and then shrunk slightly before stabilizing in size through the Middle Pre-Pottery Neolithic. We see no evidence that sex ratio, or climatic factors influenced this trend. Instead, we explore the role of human impacts on gazelle populations and their habitats as they grew in earnest at the beginning of the Late Epipaleolithic when people first began to settle into more permanent communities. Initially, in the Early and Late Natufian, anthropogenic impacts related to more intensive hunting and the increased footprint of more permanent settlements on the landscape. This may have pushed gazelle numbers below what could be supported by the environment, thus increasing the amount of food available for each animal and hence average body size. Later, as humans began to cultivate plants, manage animals and establish permanent villages, avoidance of humans and livestock by gazelle, and greater stability in food and water availability provided by agriculture, may have similarly reduced gazelle population size and intraspecific competition, thus allowing individual animals to grow larger on average.

Multi‐Decadal Simulation of Marsh Topography Under Sea Level Rise and Episodic Sediment Loads

AbstractCoastal marsh within Mediterranean climate zones is exposed to episodic watershed runoff and sediment loads that occur during storm events. Simulating future marsh accretion under sea level rise calls for attention to: (a) physical processes acting over the time scale of storm events and (b) biophysical processes acting over time scales longer than storm events. Using the upper Newport Bay in Southern California as a case study, we examine the influence of event‐scale processes on simulated change in marsh topography by comparing: (a) a biophysical model that integrates with an annual time step and neglects event‐scale processes (BP‐Annual), (b) a physical model that resolves event‐scale processes but neglects biophysical interactions (P‐Event), and (c) a biophysical model that resolves event‐scale physical processes and biophysical processes at annual and longer time scales (BP‐Event). A calibrated BP‐Event model shows that large (>20‐year return period) episodic storm events are major drivers of marsh accretion, depositing up to 30 cm of sediment in one event. Greater deposition is predicted near fluvial sources and tidal channels and less on marshes further from fluvial sources and tidal channels. In contrast, the BP‐Annual model poorly resolves spatial structure in marsh accretion as a consequence of neglecting event‐scale processes. Furthermore, the P‐Event model significantly overestimates marsh accretion as a consequence of neglecting marsh surface compaction driven by annual scale biophysical processes. Differences between BP‐Event and BP‐Annual models translate up to 20 cm per century in marsh surface elevation.

Mediterranean moth diversity is sensitive to increasing temperatures and drought under climate change

Climate change affects ecosystems worldwide and is threatening biodiversity. Insects, as ectotherm organisms, are strongly dependent on the thermal environment. Yet, little is known about the effects of summer heat and drought on insect diversity. In the Mediterranean climate zone, a region strongly affected by climate change, hot summers might have severe effects on insect communities. Especially the larval stage might be sensitive to thermal variation, as larvae—compared to other life stages—cannot avoid hot temperatures and drought by dormancy. Here we ask, whether inter-annual fluctuations in Mediterranean moth diversity can be explained by temperature (TLarv) and precipitation during larval development (HLarv). To address our question, we analyzed moth communities of a Mediterranean coastal forest during the last 20 years. For species with summer-developing larvae, species richness was significantly negatively correlated with TLarv, while the community composition was affected by both, TLarv and HLarv. Therefore, summer-developing larvae seem particularly sensitive to climate change, as hot summers might exceed the larval temperature optima and drought reduces food plant quality. Increasing frequency and severity of temperature and drought extremes due to climate change, therefore, might amplify insect decline in the future.

Evaluation of simple and multivariate linear regression models for exchangeable base cation conversion between seven measurement techniques on South African soils

Conversions of exchangeable base cation concentrations between different analytical methods are required for comparisons of soil test results with norm values developed using specific methods. Different methods vary in extraction efficiency due to underlying chemical mechanisms of cation exchange. There is a lack of knowledge pertaining to the combined effects of soil physicochemical properties on the accuracy and parsimony of conversion models. Thus, the aim of this study was to develop equations for conversion of exchangeable base cation (Ca, Mg, K and Na) concentrations between seven different methods of measurement for soils dominated by moderate-activity clays. Additional objectives included the discussion of chemical mechanisms influencing nutrient extraction efficiency, development of root mean square error (RMSE) thresholds for model selection, and evaluation of the effects of soil physicochemical properties on model performance. The ammonium acetate (1 M and 0.2 M, pH = 7), compulsive exchange, Ambic-I, Mehlich-III, Bray-II and Citric acid (1%) soil test methods were performed on 57 soils from a Mediterranean climatic zone. Simple linear regressions (SLR) as well as multivariate linear regressions (MLR) incorporating soil physicochemical properties as parameters were developed. The accuracy of cross-validated models was comparable to accuracy of predictions for samples included in calibration. MLR equations (RMSECV = 1.4–1.6 cmolc kg−1, 0.4 cmolc kg−1, 16–20 mg kg−1 and 25–40 mg kg−1 for Ca, Mg, Na and K, respectively) were generally more accurate than SLR models. Relationships between Ca content extracted by different methods depended on soil alkalinity. Use of the developed SLR or MLR models to convert nutrient quantities between different methods should be chosen based on contextual accuracy requirements.

Passive Night Cooling Potential in Office Buildings in Continental and Mediterranean Climate Zone in Croatia

The envelope is one of the most important driving factors in the energy efficiency of buildings. Typical for office and commercial buildings, curtain wall facades allow solar heat gains to be used during the winter but can lead to difficulties in reducing the cooling load during summer. The cooling load is dominant in most building types in the temperate maritime climate, while in the temperate continental climate, it is dominant mainly in office and commercial buildings. The goal of this research was to determine the potential of night passive cooling in an office building model in the most populated urban areas in Croatia-Zagreb and Split, which are located in two different climate zones. Suitable to the climate on-site, an appropriate building envelope and various types of passive and mechanical ventilation systems were selected for each location and case. Additional factors included and analysed were climate conditions, heat gains, the heat accumulation of the building, night ventilation through openings, unwanted air infiltration, and cooling loads. Through a detailed description of the model, passive cooling potential calculations, and Computer Fluid Dynamics (CFD) simulations, the results showed a potential of up to 43.5% savings in the cooling energy need for the temperate continental climate and 32.2% in the temperate marine climate. It was found from the analysis that night ventilation is expected to cool down the building enough to delay a need for cooling by several hours and improve fresh air requirements, thus saving power for cooling, and effectively reducing the need for air conditioning.

Effectiveness of phase change material in improving the summer thermal performance of an office building under future climate conditions: An investigation study for the Moroccan Mediterranean climate zone

The rise in global temperature due to the climate change phenomenon would increase the severity of summer season in the future. The integration of phase change materials (PCM) into the building envelope has been considered as one of the most promising measures to improve the thermal performance of buildings. This paper aims at investigating the effectiveness of the PCM in improving summer thermal performance of buildings under the climate conditions of the next three decades. The moderate scenario RCP4.5 of the Intergovernmental Panel on Climate Change was used to simulate future climate conditions. The present study was conducted for two building case studies: free-running and air-conditioned office buildings located in the north of Morocco (Mediterranean climate with hot summer). The findings have disclosed that an appropriate selection of the PCM melting temperature could enhance the thermal performance by 9.87 % for the free-running building and by 20.5 % for the air-conditioned building case over the whole building lifespan (30 years). A decade-by-decade analysis showed that the effectiveness of the optimum selected PCM would slightly decline over time. The research involved an economic analysis of the air-conditioned building case study. The latter led to calculating the maximum allowable cost of the PCM installation to achieve a payback period within the lifespan of the building. The findings of the present work can be used as guidelines to design office buildings integrated with PCM in the Mediterranean region.

Vibriosis Outbreaks in Aquaculture: Addressing Environmental and Public Health Concerns and Preventive Therapies Using Gilthead Seabream Farming as a Model System.

Bacterial and viral diseases in aquaculture result in severe production and economic losses. Among pathogenic bacteria, species belonging to the Vibrio genus are one of the most common and widespread disease-causing agents. Vibrio infections play a leading role in constraining the sustainable growth of the aquaculture sector worldwide and, consequently, are the target of manifold disease prevention strategies. During the early, larval stages of development, Vibrio species are a common cause of high mortality rates in reared fish and shellfish, circumstances under which the host organisms might be highly susceptible to disease preventive or treatment strategies such as vaccines and antibiotics use, respectively. Regardless of host developmental stage, Vibrio infections may occur suddenly and can lead to the loss of the entire population reared in a given aquaculture system. Furthermore, the frequency of Vibrio–associated diseases in humans is increasing globally and has been linked to anthropic activities, in particular human-driven climate change and intensive livestock production. In this context, here we cover the current knowledge of Vibrio infections in fish aquaculture, with a focus on the model species gilthead seabream (Sparus aurata), a highly valuable reared fish in the Mediterranean climatic zone. Molecular methods currently used for fast detection and identification of Vibrio pathogens and their antibiotic resistance profiles are addressed. Targeted therapeutic approaches are critically examined. They include vaccination, phage therapy and probiotics supplementation, which bear promise in supressing vibriosis in land-based fish rearing and in mitigating possible threats to human health and the environment. This literature review suggests that antibiotic resistance is increasing among Vibrio species, with the use of probiotics constituting a promising, sustainable approach to prevent Vibrio infections in aquaculture.

Determination of Saturated and Unsaturated Fatty Acids in Second Crop Season Peanut Cultivation in the Eastern Mediterranean

In this study; the saturated and unsaturated fatty acid composition of 11 different peanut cultivars, Runner (Georgia Green) Virginia (NC-7, Masal, Halisbey, Wilson, Com, Brantley, Duzici-1) Spanish (Florispan, Nigeria-1), widely grown in the eastern Mediterranean Transition Zone were determined. The research was carried out for two years (2020 to 2021) under second crop season conditions in the trial areas of the Oil Seeds Research Institute. The experiment was set up in a randomized block design with 3 replications. In the research, palmitic acid, stearic acid, arachidonic acid, oleic acid, linoleic acid, oleic/linoleic ratio, iodin value, behenic acid, arachidic acid properties were investigated. The highest oleic acid ratio was obtained from Masal (79.71%), the highest palmitic acid from florispan (11.06%), and the highest linoleic acid (34.08%) from florispan. The behenic acid ratio was found between 2.51% (Wilson) and 3.14% (Georgia Green).

Effect of climate change on fir forest communities in the mountains of South-central Greece

The endemic oro-Mediterranean fir (Abies spp.) forests in Greece are valuable ecosystems with high ecological and economic importance. In the mountains in south-central Greece, the availability of moisture plays a crucial role in the floristic composition, structure and distribution of fir forest communities. Because of the predicted adverse climate changes for the Mediterranean zone, suitability of many habitats for the growth of fir forests will change. This study aims to quantify the degree to which these forests will be affected by climate change. Current and future climatic conditions in the area studied were estimated for two periods of time (2041 – 60, 2061 – 80) and two climate change scenarios (RCP 4.5, RCP 8.5). Vegetation releves were classified and ordinated. Recursive partitioning was used to reveal the most important factor for discriminating the main plant communities and determining the ecological threshold between them. Current and future suitability of bioclimatic space for fir forest communities was identified. The effect of climate change was assessed based on predicted changes in the potential distribution, in terms of size and location, of fir forest communities. Two plant communities that reflect the differentiation of fir forests into xerophytic and mesophytic forest types are described. Among several climatic variables, spring drought was the best factor discriminating these two forest communities. The quantification of the threshold for drought in these two plant communities was used to predict their potential distribution in the area studied. Potential distribution of fir forests in south-central Greece will change in the future, due to a reduction in suitable bioclimatic space and shift to higher altitudes. The effect is expected to be greater for xerophytic forest communities, especially in the worst-case scenario (RCP 8.5) and in 2061–80.

Existing evidence on the impacts of within-field farmland management practices on the flux of greenhouse gases from arable cropland in temperate regions: a systematic map

BackgroundReducing the emissions of greenhouse gases (GHGs) is vital for mitigating climate change and meeting commitments to international agreements such as the COP 21 Paris Agreement of 2015. Agriculture is reported to account for approximately 11 percent of total global GHG emissions such that: the agricultural sector has an important role to play in meeting climate change mitigation objectives. However, there is currently little consensus on how farm management and interventions, along with interactions with in-field variability, such as soil type, affect the production and assimilation of GHGs in arable crop lands. Practical recommendations for farmers are often vague or generalised, and models (e.g. on the amount of nitrogen fertiliser applied) are used despite limited understanding of the influence of local conditions, such as the importance of soil type. Here, we report the findings of a systematic map of the evidence relating to the impact on GHG flux from the in-field management of arable land in temperate regions.MethodsWe searched for, collated and catalogued research relating to the effects of in-field arable farming practices in temperate systems on GHG emissions. Results from 6 bibliographic databases, a web-based search engine and organisational websites were combined with evidence from stakeholders. Duplicates were removed and the results were then screened for relevance at title and abstract, and full-text levels according to a predefined set of eligibility criteria (following consistency checking). Relevant studies were then coded and their meta-data extracted and used to populate a systematic map database describing each study’s settings, methods and measured outcomes.ResultsThe mapping process identified 538 relevant studies from 351 articles. Nearly all of these (96%) were found from traditional research papers, with 42% from European countries and nearly half (203 studies) lasting for 12 months or less. Over half of all studies (55%) investigated multiple interventions with chemical fertiliser (n = 100), tillage (n = 70), and organic fertiliser (n = 30) the most frequently studied single intervention types. When combining individually studied and multiple interventions, the top three intervention types most frequently studied were: chemical fertiliser (n = 312); organic fertiliser (n = 176) and tillage (n = 158). Nitrous oxide was the most commonly studied outcome, with over double the number of studies compared to carbon dioxide, the next most studied outcome. Sandy loam and silty loam were the most commonly studied soils but there was a good distribution of studies across other types. However, studies predominately focused on humid sub-tropical (Cfa) and temperate oceanic (Cfb) climates, with hot summer Mediterranean (CSa) and warm summer Mediterranean (Csb) climate zones less represented.ConclusionsThe mapping process identified clusters of research for chemical and organic fertiliser especially in relation to nitrous oxide emissions and for both carbon dioxide and nitrous dioxide in relation to tillage. Therefore, there is potential for further synthesis for these interventions. The spread of research across soil textures and in the humid sub-tropical and temperate oceanic climates may enable further synthesis to provide tailored in-field advice for farmers and provide an evidence base to inform subsidies policy. However, smaller amounts of research relating to biochar, cover crops, crop rotation, and nitrogen inhibitors highlight gaps where further research would be beneficial.

Relevance of monocrystalline and thin-film technologies in implementing efficient grid-connected photovoltaic systems in historic buildings in Port Fouad city, Egypt

This study explores the potential of integrating PV technologies on pitched roofs in Port Fouad City, Egypt, that represent the dominant style of heritage buildings in coastal cities in the Mediterranean Sea zone, considering the challenges that affect the relevance of preserving the architectural identity. This research starts with the filtration step to shortlist the relevant PV technologies, followed by the simulation step using PVsol Premium for all roof surfaces. Finally, an optimization step is performed to achieve the optimum design. According to the simulation analysis, monocrystalline and thin-film technologies dominate the results. In contrast, installation of polycrystalline technology is inadequate in such type of villas under similar weather conditions in terms of their performance ratio (PR), PV generated energy, and annual yield. Moreover, despite the light weight of the thin-film tile, we observe that the monocrystalline array is more preferable than the thin film owing to its lightest overall weight and least covered area. The optimization results indicated that monocrystalline provides the highest PR (79.4%) and annual yield (1715.1 kW h/kWp) with the smallest covered roof area (7.2 m2) and total weight (78.2 kg), whereas thin-films are more relevant in terms of color complement based on architectural theme.

N2 fixation is less sensitive to changes in soil water content than carbon and net nitrogen mineralization

Biogeochemical processes catalyzed by soil microorganisms depend on the soil water content (SWC). Yet, little is known about the sensitivity of non-symbiotic N2 fixation to changes in SWC in comparison to carbon (C) and net nitrogen (N) mineralization. Therefore, we determined the rates of N2 fixation, C mineralization, and net N mineralization in soils at five SWCs that were created by water addition to the field-moist soil (rewetting), resulting in SWCs of 20, 40, 60 and 80% of the soil water holding capacity (WHC) which correspond to 14, 28, 42, and 57% water-filled pore space (WFPS). The soils originated from an arid, semiarid, Mediterranean, and humid site located in the Coastal Cordillera of Chile. The N2 fixation rate was measured immediately after the adjustment of the SWC and additionally after a five-day pre-incubation period. We found that the rates of all three processes where higher in the rewetted soils compared to the field-moist soils, but the sensitivity to changes in SWC differed between the processes. N2 fixation tended not to increase with increasing SWC beyond 20% WHC. Furthermore, the N2 fixation rate increased faster after rewetting in the soils of the semiarid and Mediterranean zone than in the soil of the humid zone. In contrast, C mineralization reached the highest rate at 80% WHC in the soil of the humid zone and at 60% and 80% WHC in the soils of the other three climate zones. The net N mineralization rate was highest at 40% and 60% WHC in the soils of the semiarid and Mediterranean zone, and was significantly decreased at 80% WHC compared to 60% WHC. Our study shows, first, that N2 fixation is less sensitive to changes in SWC than C and net N mineralization and tends to be already at its maximum in a given soil at low SWC, i.e., 20% WHC. This is likely because the diffusion of N2 in soil does not increase with the SWC, in contrast to the diffusion of organic solutes which are the substrate of C and N mineralization. Second, our results indicate that the N2 fixation rate increases more quickly in response to rewetting of soils of the more arid climate zones than of the humid zone, which might indicate a microbial adaptation to the climate conditions. The results have important implications since they suggest that the N2 fixation rate is likely less affected than the C and net N mineralization rates by decreases in the SWC that might occur more frequently in the future due to climate change.

The salinity origin and hydrogeochemical evolution of groundwater in the Oued Kert basin, north‐eastern of Morocco

Water scarcity in the Rif region of northwestern Morocco, particularly in the Kert plain, has resulted in significant groundwater exploitation to achieve human and socioeconomic objectives. These methods helped in identification of the source of dissolved elements and the mechanism that increased groundwater salinization. Current study is the part of groundwater's salinity sources and hydrogeochemical development in the Oued Kert basin (Mediterranean zone, Driouch province, eastern Morocco); 46 samples (45 wells and one spring) were collected in June 2021. Using the Cl-/Br- ratio, which appears to be a good tracer for detecting non-atmospheric Cl- contributions to groundwater provided chemical analyses are accurate since its variability is limited. To achieve this goal, processes that increase groundwater salinization was studied. The results indicate that the groundwater samples studied had medium to high conductivity electric, which can attain 9500 S/cm. The regional distribution of physicochemical parameters is consistent with the distribution of alluvial and evaporate rocks. The high molar ratio values of Sr2+/SO42− and Sr2+/Ca2+ imply an extra input of strontium, likely through carbonate precipitation/dissolution processes as well as adsorption reactions. The varied Bromide concentrations (1-7 mg/L) detected in groundwater samples were evaluated against the binary mixing model to determine the salinization mechanisms responsible for the analyzed system. It suggests that evaporate rocks dissolution was the predominant source of groundwater mineralization in the studied region. However, irrigation of water inflows and local saltwater intrusion seems to alter aquifer quality dramatically.

GIS-Based Modeling for Vegetated Land Fire Prediction in Qaradagh Area, Kurdistan Region, Iraq

This study aims to estimate the susceptibility of fire occurrence in the Qaradagh area of the Iraqi Kurdistan Region, by examining 16 predictive factors. We selected these predictive factors, dependent on analyzing and performing a comprehensive review of about 57 papers related to fire susceptibility. These papers investigate areas with similar environmental conditions to the arid environments as our study area. The 16 factors affecting the fire occurrence are Normalized Difference Vegetation Index (NDVI), slope gradient, slope aspect, elevation, Topographic Wetness Index (TWI), Topographic Position Index (TPI), distance to roads, distance to rivers, distance to villages, distance to farmland, geology, wind speed, relative humidity, annual temperature, annual precipitation, and Land Use and Land Cover (LULC). To extract fires that occurred between 2015 and 2020, 121 scenes of satellite images (most of them are scenes of Sentinel-2) were used, with the aid of a field survey. In total, 80% of the data (185,394 pixels) were used for the training dataset in the model, and 20% of the data (46,348 pixels) were used for the validation dataset. Conversely, 20% of these data were used for the training dataset in the model, and 80% of the data were used for the validation dataset to check the model’s overfitting. We used the logistic regression model to analyze the multi-data sites obtained from the 16 predictive factors, to predict the forest and vegetated lands that suffer from fire. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to evaluate the accuracy of the proposed models. The AUC value is more than 84.85% in all groups, which shows very high accuracy for both the model and the factors selected for preparing fire zoning maps in the studied area. According to the factor weight results, classes of LULC and wind speed gained the highest weight among all groups. This paper emphasizes that the used approach is useful for monitoring shrubland, grassland, and cropland fires in other similar areas, which are located in the Mediterranean climate zone. Besides, the model can be applied in other regions, taking the local influencing factors into consideration, which contribute to forest fire mitigation and prevention planning. Hence, the mentioned results can be applied to primary warning, fire suppression resource planning, and allocation work. The mentioned results can be used as prior warnings of the outbreak of fires, taking the necessary measures and methods to prevent and extinguish fires.

SAR Satellite Imagery Reveals the Impact of the Covid-19 Crisis on Ship Frequentation in the French Mediterranean Waters

The Covid-19 pandemic is the latest example in a growing number of health, social, economic, and environmental crises humanity is facing. The multiple consequences of this pandemic crisis required strong responses from governments, including strict lockdowns. Yet, the impact of lockdowns on coastal ecosystems and maritime activities is still challenging to quantify over large spatial scales in comparison to the pre-Covid period. In this study, we used an object detection algorithm on Synthetic Aperture Radar (SAR) images acquired by the two Sentinel-1 satellites to assess the impact of the Covid-19 crisis on the presence of boats before, during and after lockdown periods in the French Mediterranean Exclusive Economic Zone. During the French most severe lockdown period (March – May 2020), we observed that ship frequentation remained at the same level from March to July 2020, instead of rising towards the summer peak like in previous years. Then, ship frequentation increased rapidly to a normal level in August 2020 when restrictions were lifted. By comparing morning and evening (7:00 am and 7:00 pm) ship frequentation during this period to pre-Covid years, we observed contrasting patterns. On the one hand, morning detections were particularly high, while on the other hand evening detections were significantly lower and less concentrated in coastal touristic waters than in previous years. Overall, we found a 9% decrease in ship frequentation between the year 2020 and the 2017-2019 period, with a maximum of 43% drop in June 2020 due to the lockdown. So, the Covid -19 crisis induced only a very short-term reduction in maritime activities but did not markedly reduce the annual ship frequentation in the French Mediterranean waters. The satellite imagery approach is an alternative method that improves our understanding of the pandemic impacts at an unprecedented spatiotemporal scale and resolution.

The Dynamics of Forearc – Back‐Arc Basin Subsidence: Numerical Models and Observations From Mediterranean Subduction Zones

AbstractThe subsidence history of forearc and back‐arc basins reflects the relationship between subduction kinematics, mantle dynamics, magmatism, crustal tectonics, and surface processes. The distinct contributions of these processes to the topography variations of active margins during subduction initiation, oceanic subduction, and collision are less understood. We ran 2D elasto‐visco‐plastic numerical models including surface and hydration processes. The models show the evolution of wedge‐top and retro‐forearc basins on the continental overriding plate, separated by a forearc high. They are affected by repeated compression and extension phases. Compression‐induced subsidence is recorded in the syncline structure of the retro‐forearc basin from the onset of subduction. The 2–4 km upper plate negative residual topography is produced by the gradually steepening slab, which drags down the upper plate. Trench retreat leads to slab unbending and decreasing slab dip angle that leads to upper plate trench‐ward tilting. Back‐arc basins are either formed along inherited weak zones at a large distance from the arc or are created above the hydrated mantle wedge originating from arc rifting. Back‐arc subsidence is primarily governed by crustal thinning that is controlled by slab roll‐back and supported by the underlying mantle convection. High subduction and mantle convection velocities result in large wavelength negative dynamic topography. Collision and continental subduction are linked to the uplift of the forearc basins; however, the back‐arc records ongoing extension during a soft collision. During the hard collision, both the forearc and back‐arc basins are ultimately affected by the compression. Our modeling results provide insights into the evolution of Mediterranean subduction zones.