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Lower Mekong Basin (LMB) experiences a recurrent drought phenomenon. However, few studies have focused on drought monitoring in this region due to lack of ground observations. The newly released Climate Hazards Group Infrared Precipitation with Station data (CHIRPS) with a long-term record and high resolution has a great potential for drought monitoring. Based on the assessment of CHIRPS for capturing precipitation and monitoring drought, this study aims to evaluate the drought condition in LMB by using satellite-based CHIRPS from January 1981 to July 2016. The Standardized Precipitation Index (SPI) at various time scales (1–12-month) is computed to identify and describe drought events. Results suggest that CHIRPS can properly capture the drought characteristics at various time scales with the best performance at three-month time scale. Based on high-resolution long-term CHIRPS, it is found that LMB experienced four severe droughts during the last three decades with the longest one in 1991–1994 for 38 months and the driest one in 2015–2016 with drought affected area up to 75.6%. Droughts tend to occur over the north and south part of LMB with higher frequency, and Mekong Delta seems to experience more long-term and extreme drought events. Severe droughts have significant impacts on vegetation condition.

Project: GCOS Earth Heat Inventory - A study under the Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory (EHI), and presents an updated international assessment of ocean warming estimates, and new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period from 1960 to present. Summary: The file “GCOS_EHI_1960-2020_Inland_Water_Heat_Content_data.nc” presents an updated estimate of the global heat storage within natural lakes and artificial reservoirs for the period 1960-2020. Several improvements have been implemented in comparison with Vanderkelen et al. (2020): new approach to estimate lake volume, new lake models considered, and an extension of the analysis period. The data are used in von Schuckmann et al. (2022).

The global energy demand is growing substantially. Clean and secure energy supply is a must for our civilization's sustainable development. Solar and wind energy is growing fast and can contribute significantly to meet the goals set by many countries to reduce greenhouse gas emissions. A deep and wide investigation of the environmental impact of solar and wind energy is important before any solar or wind plants' construction is made. In this study, the literature is reviewed to summarize the environmental impact of solar and wind energy systems in terms of the following factors; land use, water consumption, impact on biodiversity, visual and noise effects, health issues, and impact on micro climate. Although the benefits of solar and wind energy are obvious and great, negative perception of these technologies can inhibit their wide penetration in some regions. This review paper includes a critical and an inclusive analysis of solar and wind energy’s environmental impact and may serve as an important tool to conduct a proper environmental impact assessment. This critical analysis may serve also as a tool for developers, policy, and decision-when planning future solar and wind farms.

La cuenca hidrográfica de Ikkour situada en la montaña del Atlas Medio (Marruecos) ha sido objeto de graves problemas de erosión del suelo. Este estudio tuvo como objetivo evaluar la susceptibilidad a la erosión del suelo en esta cuenca montañosa utilizando la Ecuación Universal de Pérdida de Suelos (USLE) e índices espectrales integrados con el entorno del Sistema de Información Geográfica (SIG). El modelo USLE requirió la integración de mapas de factores temáticos que son la agresividad de la lluvia, la longitud y la pendiente del talud, la cobertura vegetal, la erosionabilidad del suelo y las prácticas de control de la erosión. Estos factores se calcularon utilizando datos de teledetección y SIG. La evaluación basada en USLE mostró que la pérdida potencial de suelo anual total estimada fue de aproximadamente 70,66 toneladas ha-1 año-1. Esta pérdida de suelo se ve favorecida por las pendientes pronunciadas y la cubierta vegetal degradada. El método del índice espectral, que ofrece una evaluación cualitativa de la erosión hídrica, mostró diferentes grados de degradación del suelo en la cuenca del estudio según FI, BI, CI y NDVI. Los resultados de este estudio mostraron un acuerdo entre el modelo USLE y el enfoque del índice espectral, e indicaron que la tasa de erosión del suelo prevista puede deberse a la topografía más accidentada de la tierra y al aumento de las áreas agrícolas. De hecho, estos resultados pueden ayudar aún más a los responsables de la toma de decisiones en la implementación de un programa de protección adecuado para reducir la erosión del suelo. Le bassin versant d'Ikkour situé dans la montagne du Moyen Atlas (Maroc) a fait l'objet de graves problèmes d'érosion des sols. Cette étude visait à évaluer la sensibilité à l'érosion des sols dans ce bassin versant montagneux à l'aide de l'équation universelle de perte de sol (USLE) et d'indices spectraux intégrés à l'environnement du système d'information géographique (SIG). Le modèle USLE a nécessité l'intégration de cartes de facteurs thématiques qui sont l'agressivité des précipitations, la longueur et la pente de la pente, la couverture végétale, l'érodabilité des sols et les pratiques de contrôle de l'érosion. Ces facteurs ont été calculés à l'aide de données de télédétection et de SIG. L'évaluation basée sur l'USLE a montré que la perte potentielle totale annuelle estimée des sols était d'environ 70,66 tonnes ha−1 an−1. Cette perte de sol est favorisée par les pentes abruptes et la couverture végétale dégradée. La méthode de l'indice spectral, offrant une évaluation qualitative de l'érosion hydrique, a montré différents degrés de dégradation des sols dans le bassin versant d'étude selon FI, BI, CI et NDVI. Les résultats de cette étude ont montré un accord entre le modèle USLE et l'approche de l'indice spectral, et ont indiqué que le taux d'érosion du sol prédit peut être dû à la topographie des terres les plus accidentées et à une augmentation des zones agricoles. En effet, ces résultats peuvent aider davantage les décideurs à mettre en œuvre un programme de conservation approprié pour réduire l'érosion des sols. The Ikkour watershed located in the Middle Atlas Mountain (Morocco) has been a subject of serious soil erosion problems. This study aimed to assess the soil erosion susceptibility in this mountainous watershed using Universal Soil Loss Equation (USLE) and spectral indices integrated with Geographic Information System (GIS) environment. The USLE model required the integration of thematic factors' maps which are rainfall aggressiveness, length and steepness of the slope, vegetation cover, soil erodibility, and erosion control practices. These factors were calculated using remote sensing data and GIS. The USLE-based assessment showed that the estimated total annual potential soil loss was about 70.66 ton ha−1 year−1. This soil loss is favored by the steep slopes and degraded vegetation cover. The spectral index method, offering a qualitative evaluation of water erosion, showed different degrees of soil degradation in the study watershed according to FI, BI, CI, and NDVI. The results of this study displayed an agreement between the USLE model and spectral index approach, and indicated that the predicted soil erosion rate can be due to the most rugged land topography and an increase in agricultural areas. Indeed, these results can further assist the decision makers in implementation of suitable conservation program to reduce soil erosion. كان مستجمع مياه إيكور الواقع في جبل الأطلس الأوسط (المغرب) موضوعًا لمشاكل خطيرة تتعلق بتآكل التربة. تهدف هذه الدراسة إلى تقييم حساسية تآكل التربة في مستجمعات المياه الجبلية هذه باستخدام معادلة فقدان التربة العالمية (USLE) والمؤشرات الطيفية المتكاملة مع بيئة نظام المعلومات الجغرافية (GIS). يتطلب نموذج USLE تكامل خرائط العوامل المواضيعية وهي شدة هطول الأمطار، وطول المنحدر وانحداره، والغطاء النباتي، وقابلية تآكل التربة، وممارسات مكافحة التعرية. تم حساب هذه العوامل باستخدام بيانات الاستشعار عن بعد ونظم المعلومات الجغرافية. أظهر التقييم القائم على USLE أن إجمالي الخسارة السنوية المحتملة للتربة كان حوالي 70.66 طن هكتار-1 سنة-1. ويفضل فقدان التربة هذا المنحدرات الشديدة والغطاء النباتي المتدهور. أظهرت طريقة المؤشر الطيفي، التي تقدم تقييمًا نوعيًا للتآكل المائي، درجات مختلفة من تدهور التربة في مستجمعات المياه في الدراسة وفقًا لـ FI و BI و CI و NDVI. أظهرت نتائج هذه الدراسة وجود اتفاق بين نموذج USLE ونهج المؤشر الطيفي، وأشارت إلى أن معدل تآكل التربة المتوقع يمكن أن يكون بسبب تضاريس الأراضي الأكثر وعورة وزيادة في المناطق الزراعية. في الواقع، يمكن أن تساعد هذه النتائج صناع القرار بشكل أكبر في تنفيذ برنامج الحفظ المناسب للحد من تآكل التربة.

The influence of total solid contents during anaerobic mesophilic treatment of the organic fraction of municipal solid waste (MSW) has been studied in this work. The work was performed in batch reactors of 1.7L capacity, during a period of 85-95 days. Two different organic substrate concentrations were studied: 931.1 mgDOC/L (20% TS) and 1423.4 mgDOC/L (30% TS). Experimental results showed that the reactor with 20% total solids content had significantly higher performance. Thus, the startup phase ended at 14 days and the total DOC removal was 67.53%. The startup in reactor R30 ended at 28 days obtaining 49.18% DOC removal. Also, the initial substrate concentration contributed substantially to the amount of methane in the biogas. Hence, the total methane production in the methanogenic phase was 7.01 L and 5.53 L at the end of the experiments for R20 and R30, respectively.

Abstract This study builds on previous studies and proposes a combined approach for shortlisting and selecting representative climate simulations for impact studies in the Souss watershed in Morocco. The selection procedure consists of selecting climate simulations on the basis of predicted changes in means and extremes, climate model performance in simulating past climate and bias correction. Unlike the selection methods proposed in the literature that begin with a pre-selection of simulations based on changes in means, the approach recommended in this study involves an initial pre-selection of simulations by the ability of the models to simulate the base period climate. The proposed procedure involved selecting a set of general circulation models (GCMs) from the Phase 5 Coupled Model Intercomparison Project (CMIP5) and regional climate models (RCMs) from the Coordinated Regional Downscaling Experiment (CORDEX) project to project spatiotemporal changes in precipitation and temperature for the RCP4.5 and RCP8.5 scenarios. Climate changes between 1975–2005 and 2066–2095 were analyzed for the watershed. By 2066–2095, precipitation is projected to decrease by -12.2 to -30.1% under the RCP4.5 scenario and by -5.2 to -65.4% under the RCP8.5 scenario. Mean temperature is projected to increase by 2.3 to 2.6°C under RCP4.5 and by 4.4 to 4.7% under RCP8.5. For both scenarios, a decline in precipitation is projected while temperature is expected to increase. The Palmer Drought Severity Index (PDSI) revealed that the Souss watershed, characterized by incipient drought during the historical period, will experience mild and moderate drought in 2066–2095 under the RCP4.5 and RCP8.5 scenarios, respectively.

In this work, we conducted a study that is to bleach wastewater model solutions loaded with dyes of indigo and sulfur black, while using and optimizing the process of hybridized treatment of textile effluents by torque of coagulation-ultrafiltration (CO-UF). According to the separate optimization of coagulation processes (optimum dose of the coagulant (lime) and ultrafiltration membrane (hydrodynamic characterization of the membrane based on polysulfone (PSU)), we combined the two methods in order to increase performance fading exploited colored waters. The results of the rate of discoloration separated by the methods of coagulation and ultrafiltration are respectively of the order of 33.55% and 80.36% for the water loaded with indigo and of the order of 25.33% and 60.78% for those charged with the black sulfur. While the results of the bleaching obtained by the hybrid method CO-UF have shown that the bleaching rate was calculated as around 98% for the indigo and of the order of 92% for the black sulfur, obviously very interesting with respect to the coagulation and ultrafiltration used separately. Moroccan Journal of Chemistry, Vol. 4, No 1 (2016)

The European Union is currently in the process of transformation toward a circular economy model in which different areas of activity should be integrated for more efficient management of raw materials and waste. The wastewater sector has a great potential in this regard and therefore is an important element of the transformation process to the circular economy model. The targets of the circular economy policy framework such as resource recovery are tightly connected with the wastewater treatment processes and sewage sludge management. With this in view, the present study aims to review existing indicators on resource recovery that can enable efficient monitoring of the sustainable and circular solutions implemented in the wastewater sector. Within the reviewed indicators, most of them were focused on technological aspects of resource recovery processes such as nutrient removal efficiency, sewage sludge processing methods and environmental aspects as the pollutant share in the sewage sludge or its ashes. Moreover, other wide-scope indicators such as the wastewater service coverage or the production of bio-based fertilizers and hydrochar within the wastewater sector were analyzed. The results were used for the development of recommendations for improving the resources recovery monitoring framework in the wastewater sector and a proposal of a circularity indicator for a wastewater treatment plant highlighting new challenges for further researches and wastewater professionals.