Abstract: The equation of time (EoT) tracks daily deviations in length between the solar day and the mean day. Since the length of the mean day remains constant throughout the year, the EoT must mirror daily fluctuations in the length of the solar day. Furthermore, if the Sun meridian declination (SMD) is dynamically linked to Earth’s rotational speed (ERS) the EoT must obey to oscillations in ERS. This document examines the position, velocity, acceleration, and net drive of the mean-time Sun within a solar sundial noon analemma considering both its vertical and horizontal dimensions: the SMD and the EoT. Evidence supports that ERS decreases monotonically along two trans-equinoctial analemmatic phases in which the net drives of the EoT and SMD become coordi-nated (either both accelerating or both decelerating) within the SMD interval of −16 to +19 arcdeg, centered at +3. Conversely, ERS increases monotonically along two trans-solstitial analemmatic phases in which the net drives of the EoT and SMD become opposed, outside the specified interval of SMD. The ERS reaches its minima and maxima at the troughs and crests of the EoT; whereas it varies respectively.

Abstract: Biopesticides are alternatives to synthetic ones, repel insects and control diseases in a sustainable way. The objective was to evaluate the efficiency and efficacy of a biopesticide. In apples in 2023 and walnut in 2024, both in Coahuila, Mexico. In 2023, with: A.- Without application and B.- With application of 2 L of biopesticide one liter at the beginning and the second 10 days later, with three repetitions. In Walnut A.- With synthetic insecticide and fungicide and B.- With the application of the biopesticide. The repellency index at 20 days after application (DDA) the control reached 5.3 and the biopesticide with 1 butterfly, the repellency index at 20 DDA, 0.39 and the effectiveness of the biopesticide was 75.3%. In walnut, the repellency of the synthetic was 0.25 at 20 DDA and of the biopesticide was 1.5. In apple tree diseases, the severity without application was 6.75 % and the biopesticide 1.67 %, in walnut with synthetic the severity was 2.0 % and the biopesticide 5.21, %, the effectiveness of the biopesticide was 61.6%. The repellency is less than one and the effectiveness is greater than 60% with Mexican standards.

Abstract: Accurate vegetation mapping is essential to enhance understanding of important ecosystem processes such as fire behaviour, nutrient cycling, plant community composition and mega-herbivore population dynamics in African savannahs.The inherent heterogeneity of savannah landscapes however creates significant challenges for accurate discrimination of vegetation components. Recent studies based on the use of optical remote sensing data favour very high spatial resolution (VHR) multi-spectral imagery for dealing with this challenge. However, such data are costly for use in operational management. Planet Labs, through Norway’s International Climate and Forests Initiative (NICFI) in partnership with Kongsberger Satellite Services (KSAT) and Airbus, now grant free access to high-resolution, analysis-ready mosaics of Planet imagery over the tropics, with great potential for fine-scale vegetation mapping. However, the spectral characteristics of these data are limited, with little knowledge of their ability to resolve the spectral similarity of heterogeneous savannah vegetation components. In parallel, Sentinel-2 samples a relatively high number of spectral bands, but has relatively coarse spatial resolution for dealing with the high spatial heterogeneity in African savannah landscapes. We test the hypothesis that fusing Sentinel-2 with Planet imagery leverages their spectral and spatial advantages to enhance accurate discrimination of savannah vegetation types. To achieve this, Principal Component and Gram-Schmidt transformations were compared for image fusion via pan-sharpening, where the Gram-Schmidt approach proved superior. Using this approach, we fused Sentinel-2 and Planet images and compared the three datasets (i.e. Sentinel-2, Planet and Fused images) augmented with two spectral indices and three Haralick texture features in a multi-layer perceptron neural network classification within a test site in the Lower Sabie region of Kruger National Park, South Africa. Overall, the Fused image achieved the best and most precise classification accuracy metrics (weighted F-score: 0.87±0.012) compared to Sentinel-2 (weighted F-score: 0.85±0.034) and Planet imagery (weighted F-score: 0.85±0.017). A comparison of classifications showed loss in spatial detail when using Sentinel-2 (at 10 meters spatial resolution), yet similar thematic details for vegetation classes across all three datasets. Our findings highlight the utility of Sentinel-2 and the Planet-NICFI mosaics in a heterogeneous savannah landscape, while setting a foundation for cost-effective and accurate high spatial resolution monitoring of savannah ecosystem.

Abstract:

Recent work demonstrated 50:50 sand-recycled polycarbonate (rPC) composites have an average compressive strength of 71MPa, which dramatically exceeds the average offered by commercial concrete (23.3-30.2MPa). Due to the promising technical viability of replacing carbon-intensive concrete with recycled sand plastic composites, this study analyzes the cradle-to-gate environmental impacts with a life cycle assessment (LCA). 50:50 sand-to-plastic composites at different sample sizes were fabricated and the electricity consumption monitored. Cumulative energy demand and IPCC global warming potential 100a were evaluated to quantify energy consumption and greenhouse gas emission associated with sand-plastic brick and two types of concrete, spanning the lifecycle from raw materials extraction to use phase. The results showed that at small sizes using Ontario grid electricity, the composites are more carbon intensive than concrete, but as samples increase to standard brick scale rPC composite bricks demonstrate significantly lower environmental impact, emitting 96% less CO₂/cm³ than sand-virgin PC(vPC) composite, 45% less than ordinary concrete, and 54% less than frost-resistant concrete. Energy sourcing has a significant influence on emissions. Sand-rPC composite achieves a 67%-98% lower carbon footprint compared to sand-vPC composite and a 3%-98% reduction compared to both types of concrete in different production rate. Recycling global polycarbonate production for use in sand-rPC composite although small compared to the total market could annually displace approximately 26 Mt of concrete, saving of 4.5-5.4 Mt of CO₂ emissions. The results showed twin problems of carbon emissions form concrete and poor plastic recycling could be partially solved with sand-rPC building material composites to replace concrete.

Abstract: Historical tempera paints exposed to pollutant gases suffer chemical and mineralogical deterio-ration which manifest through physical changes. Knowledge about these changes is fundamental to develop strategies for preventive conservation of wall paintings. In this research, binary tem-pera mock-ups composed of calcite, gypsum or lead white mixed with a proteinaceous binder (i.e., egg yolk or rabbit glue) were exposed to an ageing test by SO2-rich atmosphere exposure to learn about the degradation mechanisms and forms related to the pigment-binder interaction. Reference (unaltered) and aged mock-ups were studied from a physical point of view, characterizing the morphological changes by stereomicroscope and profilometry, colour variations by spectropho-tometry, gloss changes, and reflectance changes by hyperspectral camera. Also, mineralogical and chemical changes were studied by means of x-ray diffraction, Fourier transform infrared spec-troscopy and scanning electron microscopy with energy-dispersive x-ray spectroscopy. Egg yolk-based paints showed higher chromatic changes than their counterparts made of rabbit glue binder. Also, sulphate and sulphite salts precipitated on the surface of the aged paints re-gardless of their binder, influencing the painting reflectance which subsequently increased. Egg yolk-based mock-ups exhibited roughness increases while the rabbit glue-based paints showed roughness reduction, with exception of lead white-based paints. Therefore, an important influence of the type of binder and the interaction between the binder and the pigment on the durability of tempera paints in atmospheres rich in SO2 was confirmed.

Abstract: End-of-life (EoL) management of solar panel waste has emerged as an important issue related to first-generation solar panels in South Korea, which have already entered their retirement stage. In this study, the sustainability impacts of three scenarios for recycling EoL solar panels, namely, mechanical recycling (MR), chemical recycling (CR), and thermal recycling (TR) were investigated and their environmental and economic benefits were evaluated using the life cycle sustainability assessment (LCSA) method, with landfilling as the reference scenario. The results obtained showed a high global warming potential (GWP) as well as acidification for MR owing to the additional burden of transportation and industrial processes associated with MR. For CR, the use of chemicals and subsequent landfilling resulted in approximately 4.7 times higher terrestrial ecotoxicity than was observed for the landfilling scenario. Further, the GWP of TR was approximately 1.5 times higher that of CR owing to its high energy consumption. However, its environmental burden was generally lower than those of MR and CR. The results of this study, which capture the current situation of EoL PV panels in South Korea, can be employed to facilitate the establishment of regulations that ensure sustainable management in this regard.

Abstract: Water is one of the most valuable and essential resources for human life, yet its scarcity has become a pressing global issue exacerbated by climate change and population growth. To address the increasing demand for water driven by urbanization, industrial expansion, tourism, and agricultural needs, many countries are turning to desalination as a viable solution. This study investigates the integration of renewable energy sources (RES) with desalination technologies to enhance both sustainability and efficiency. A comprehensive review of major desalination methods has been conducted, with a particular focus on the application of solar and wind energy. Additionally, the challenges associated with renewable energy-powered desalination, including the need for effective energy storage systems and the inherent volatility of power supply were explored. Our findings indicate that coupling renewable energy with desalination not only significantly reduces carbon emissions but also enhances the sustainability of water supply systems. The study also emphasizes the importance of emerging technologies, such as hybrid energy storage systems (HESS) and machine learning (ML), in optimizing RES powered desalination processes. Ultimately, this study aims to guide future research and development initiatives, promoting the global adoption of desalination systems powered by renewable energy.

Abstract: In this study we explore the interaction between land, atmosphere and ocean and understand how they affect the intensity of extreme weather events such as cold waves, storms, floods and heat waves from the important parameters such as temperature, precipitation, wind speed, local pressure, sea level pressure, relative humidity, and dew point temperature. Our results show that when temperature drops (below 0°C), there is an increase in relative humidity and precipitation, which disturbs the cold weather conditions. A positive correlation was found between wind speed and local pressure, indicating stormy conditions. Our overall study has an implication towards the threat of climate change and extreme weather events to develop the strategies to deal with these changes.

Abstract: Global construction activity remains the least responsive large economic sector to the exigencies of global climate change. Focus has centered on operating emissions of buildings, while upfront embodied emissions in building materials remain unabated. Two of the most used building materials, steel and concrete, together produce more than 14 percent of total annual greenhouse gas emissions [1]. In contrast, softwood timber, another commonly used building material, can remove and store atmospheric carbon in buildings for decades. However, the upfront climate benefits of using structural-grade softwoods in durable building frames are limited due to the multi-decadal growth and harvest cycles. Here, we compare the use of fast-growing Brazilian Eucalyptus to a group of commonly used North American softwoods (spruce, pine, and fir) in a three-stage climate risk model that results in a novel Carbon Benefit Multiple, which quantifies the relative carbon removal benefits in a risk adjusted framework. The analysis shows that short rotation, high yield Eucalyptus is 2.7x to 4.6x better at removing atmospheric carbon than softwoods depending on various risk perception scenarios. The analysis indicates that building decarbonization can benefit by using fast growing and high yielding Eucalyptus species compared to traditionally used softwood species.

Abstract: This paper aims at addressing sustainability concerns in vulnerable insular territories. Such concerns are due to the rising overtourism phenomenon that affects islands at a rapidly escalating pace; and renders sustainable local development of these outstanding areas – from a natural and cultural viewpoint – at stake. Towards this end, this work capitalizes on current literature and attempts to structure a methodological framework and a respective set of indicators’ groups that are capable of assessing dimensions of overtourism in each single tourism destination, thus providing evidence-based and more robust guidelines for articulating policy decisions that can remedy incidents of overtourism. The proposed methodological framework follows a place-based approach and combines tourism demand and supply data with environmental, social, economic and spatial data and respective indicators for assessing tourism density and intensity of each destination’s tourism pattern and related multi-dimensional impacts. Validation of both the proposed framework and indicators’ groups is conducted in Santorini Island, Greece, i.e., an island that lies at top positions of many lists of destinations, marked as suffering by overtourism. Results show that Santorini Island is confronted with severe overtourism impacts, which are highly affecting its identity, productive model and spatial pattern, while endangering its natural and cultural wealth.