In this study, a survey was conducted to determine the public opinion regarding the acceptance of using home composters as an alternative approach for household organic waste management. This approach is introduced as a method to replace the landfilling of organic municipal solid waste, which is the main solid waste management currently employed in Palestine, considering Anabta town as a case study. The results showed that people in the target area are welcoming of the home composting idea, and about 99% of participants are interested in owning home composters at their properties, which is regarded as a good reference for implementing the proposed home composting scheme in this area. The results showed that people are interested in the new proposed scheme for organic household waste despite their minimal knowledge and understanding about the composting process’s importance and effects. The survey tested the people’s expectations and thoughts about the home composting concept and found that the main motives for home composting were reducing the cost of house gardening and using the produced compost in soil nutrition, besides being part of environmental sustainability. On the other side, obstacles were due to people’s inexperience of the home composting method, as almost half of participants were expecting an exhausting, long process to produce compost, with the related bad smell and insects during composting progression. Hence, the study found that it is important to spread awareness about the right procedures to apply home composting among participants, in line with environmental awareness campaigns through social media, and provide personalized follow-up with participants.

Environmental degradation, including air quality deterioration, has been mainly attributed to anthropogenic activities. Air pollution has become a pressing issue in industrialised and highly populated areas due to the combustion of fossil fuels and industrial operations. Recently, the COVID-19 pandemic led to a nationwide lockdown to control the spread of the coronavirus. This imposed restrictions on many economic activities, thus providing the environment with an opportunity to heal. The COVID-19 response measures adopted by most countries, including lockdown, restricted movement, and other containment measures, led to a significant decrease in energy use in the transport sector. Due to low electricity access levels in developing countries, traditional energy sources make up the bulk of energy used for most domestic energy services. Biomass combustion emits carbon monoxide (CO), while the transport sector is a major contributor of nitrogen dioxide (NO₂). This study was purposed to investigate the short-term effects of COVID-19 on CO and NO₂ concentration levels in Nairobi, Vihiga and Tana River counties. The study utilised data on CO surface concentration, NO₂ column concentration and reported COVID-19 cases. Time series, correlation analysis and spatial and temporal map analysis were carried out to investigate the changes and relationships among the study parameters. The three counties were selected based on the urbanisation and population. Nairobi county represented an urban setting, while the Vihiga and Tana River counties represented rural areas with high and low population densities, respectively. The CO surface concentrations in Nairobi and Vihiga county significantly correlated with the COVID-19 cases, with both counties portraying negative correlations, i.e., −0.59 ( P-value: 0.008) and −0.45 ( P-value: 0.05), respectively. NO₂ column concentration also exhibited a significant negative relationship with reported COVID-19 cases in the Vihiga (−0.018, P-value = 0.05) and Tana River (0.17, P-value = 0.00) counties. These findings highlight the need for demographic and economic considerations in CO and NO₂ assessments, and allude to a decreased health risk due to CO and NO₂ emissions during the COVID-19 pandemic.

Improving the accuracy of rainfall forecasts is related to the number of rain gauges needed in an area, so determining the optimal number of rain gauges is very important. This study aimed to determine the best method for calculating the optimal number of rain gauges. Generally, the calculation of the optimal number of rain gauges using the coefficient of variation only takes into account the accumulation of rainfall at the station. The distance between the location and height of the rain gauge is not taken into account. The phenomenon of rain that occurs in the tropics is very dynamic, where one place compared to another tends to have different rain intensity and duration. In addition, the height and distance factors also greatly affect the measured rainfall. Therefore, it is very important to know the best method to calculate the optimal number of rain gauges needed in a particular area. This study implements 3 methods to determine the appropriate method to be used in determining the optimal rain gauge number for urban areas: namely, World Meteorological Organization (WMO) criteria, coefficient of variation, and Kagan-Rodda. In this study, rainfall data from 2010 to 2019 at 5 locations in Makassar were used in calculating the optimal number of rain gauges required. The results showed that the optimal number of rain gauges in Makassar as an urban area following the WMO recommendation was 9–18, where small islands around it are not considered. Another result obtained is that if the rainfall data for the Sudiang area, which is located at the coordinates (119.522° E, 5.085° S), is not included in the calculation, it will greatly reduce the accuracy in determining the optimal number of rain gauges in the Makassar area.

Our paper reviews the current understanding of mercury in the environment of soil and sediment, including sampling, mobilization phases and analyzing methods. As a dangerous trace element, mercury has been shown to have several harmful effects on the environment. Mercury is released into the environment in a variety of chemical forms by both geogenic and human activities, with the majority of it coming from anthropogenic sources. It is affected by environmental conditions such as pH, redox potential, light and temperature-all of which determine its final chemical form-reactivity and toxicity. Methylmercury is considered one of the most poisonous forms found in nature. Considering the methodologies of the studies carried out we have found that the best technique for preserving methylmercury in soil and sediment samples is to freeze it immediately after collection. Organically rich soils are related to higher total mercury levels. Plants, such as Solanum nigrum (BR3) and Cynodon dactylon (BR2), can play an important role in mercury transport and accumulation. Solid-phase selenium causes faster demethylation and slower methylation of mercury. Methylmercury can increase by climate change and thawing; arctic permafrost is a potential source of Hg. Chemical vapor generation inductively coupled plasma mass spectrometry was used to develop a simple and quick method for measuring methylmercury; ultrasonic agitation and HNO₃ were used for the process, the last of which proved to be the most efficient for selective extraction of methylmercury.

A study was carried to investigate by placing a side stream filter in a cooling tower to observe the water conservation in the system. For any coal based power plant cycles of concentration plays important role for water conservation. The cycles of concentration in cooling tower was increased by installation of membrane system. The drain of the side stream filter was disposed to effluent treatment plant (ETP), while the filtered water will be recycled to the cooling tower inlet. The water parameter was measured by using various flow rates, pressure, and other factors. Significant water savings were demonstrated in the pilot. Maximum make-up water and outflow were both reduced by 14% and 48%, respectively. To save the most water, permeate recovery must be as high as possible. Water savings were minimal due to silica scaling on the membranes. Selected membranes are capable of lower total dissolved system (TDS) rejection than the 88% of total required membranes in the primary study, which might help to save water. The increased energy consumed by membrane treatment was compensated for by lower water outlays. To prevent scaling antiscalent chemical with chemical dosing system was installed along with membrane system.

Land degradation due to soil erosion is a major problem in mountainous areas. It is crucially important to understand the law of soil erosion under different land-use patterns with rainfall variability. We studied Qingshuihe Watershed in the Chongli district of the Zhangjiakou area. Four runoff plots, including caragana, corn, apricot trees, and barren grassland, were designed on the typical slopes of Xigou and Donggou locations. The 270 natural rainfall events observed from 2014 to 2016 were used to form a rainfall gradient. The relationship between runoff and sediment yield was analyzed. Results showed that the monthly rainfall of the slope runoff plot in the Chongli mountain area presented the trend of concentrated rainfall in summer, mainly from June to September, accounting for 82.4% of the total rainfall in 2014–2016, which was far higher than that in other months. Starting from April to May every year, the rainfall increased with time, then from July to September, the rainfall decreased gradually, but it was still at the high level of the whole year. Among the four ecosystems, the caragana-field has the best effect on reducing the kinetic energy of rainfall and runoff, which can effectively reduce the runoff and sediment yield of the slope and reduce the intensity of soil erosion. In terms of the total amount of runoff and sediment, the runoff and sediment yield of the caragana-field reduced by 74%–87% and 64%–86% compared with that of the grassland. Comparing different land-use types, the caragana plantation would be conducive to conserving soil and water resources.

Social activities, economic benefits, and environmental friendly approach are very much essential for a sustainable production system. This is widely observed during the Covid-19 pandemic situation. The demand for essential goods in the business sector is always changing due to different unavoidable situations. The proposed study introduces a variable demand for controlling the fluctuating demand. However, a reworking of produced imperfect products makes the production model more profitable. Partial outsourcing of the good quality products has made the production system more popular and profitable. Separate holding cost for the reworked and produced products are very helpful idea for the proposed model. Moreover, consumption of energy during various purpose are considered. Separate green investment make the model more sustainable and eco-friendly. The main focus of the model is to find the maximum profit through considering optimum value of lot size quantity, average selling price, and green investment. The classical optimization technique is utilized here for optimizing the solution theoretically. The use of concave 3D graphs, different examples, and sensitivity analyses are considered here. Furthermore, managerial insights from this study can be used for industry improvement.

The current study focuses on a two-echelon supply chain for a reliable retailer, an unreliable manufacturer, and selling price-dependent demand. Due to an unreliable manufacturer and transportation hazards, shortages arise, which negatively impact the reputation of the retailer. Moreover, customers are more conscious of the environment, as a result, most of the industry focuses on the production of green products. To reduce the holding cost of the retailer, a fuel consumption-based single-setup-multi-unequal-increasing-delivery policy was utilized in this current study. With this transportation policy, the number of shipments increases, which directly increases carbon emissions and transportation hazards. To protect the environment, the green level of the product is enhanced through some investments. The demand varies with the price of the product as well as with the level of the greenness of the product. Due to uncertain demand, the rate of the production is treated as controllable. A classical optimization technique and distribution-free approach have been utilized to obtain the optimum solution and the optimized system profit. To prove the applicability, the study is illustrated numerically and graphically via a well-explained analysis of sensitivity. The study proves that single-setup-multi-unequal-increasing delivery policy is 0.62% beneficial compared to single-setup-single-delivery policy and 0.35% better than the single-setup-multi-delivery policy.

Watersheds are naturally prone to environmental disasters such as flooding. The purpose of the study was to analyze the potential impact of flooding on the Nabaoy River Watershed using Geographic Information System (GIS) remote sensing. Secondary data for flood factors such as slope, elevation, land cover, surface run-off, rainfall, and soil were used and reclassified using the critical scale of factors of flood vulnerability ratings and weighting overlay using the GIS environment to create geospatial data on the potential impact to flooding. Data revealed the following percentages of the susceptibility of the watershed to flooding: very low (8.06%), very highly (19.79%), moderate (22.15%), high (22.84%), and low (27.16%). The main result showed that the upstream area of the Nabaoy river watershed such as Nabaoy, Napaan, Pawa, and Tag-osip was within low to very low flood vulnerability. Meanwhile, the inundation vulnerability intimidation on the downstream side of the Nabaoy river watershed such Cubay Sur, Motag, and low-lying areas of Nabaoy, Napaan, and Tag-osip have moderate to very highly susceptibility to flooding. The results obtained can help the concerned agencies and stakeholders to craft policy and water management plans, adaptive capacity, conservation measures, and resilience programs in response to severe flooding.