Environments, Volume 9, Issue 9 (September 2022) – 14 articles

Global remote sensing of solar-induced fluorescence (SIF), a proxy for plant photosynthetic activity, represents a breakthrough in the systematic observation of global-scale gross primary production and other ecosystem functions. Here, we hypothesize that all earth ecosystem variabilities, including SIF, are affected by climate variations. The main contribution of this study is to apply a global empirical orthogonal function (EOF) analysis of SIF to quantify the relations between the large-scale GPP variability and climate variations. We used 2007–2019 SIF data derived from the Global Ozone Monitoring Experiment-2 (GOME-2) satellite sensor observations and a rotated empirical orthogonal function (EOF) analysis to explore global SIF variability over years and decades. The first leading EOF mode captures the well-known ENSO pattern, with most of the variance over continents in the tropical Pacific and Indian Oceans. The second and third leading EOF modes in SIF variability are significantly related to the NAO and PDO climate indices, respectively. Our analysis also shows that the 2011 La Niña (2015 El Niño) elevated (decreased) global SIF. Full article

This study examined the last four decades of the existing academic literature related to the environmental impacts of using cover crops in agricultural production systems. Data were collected from the Web of Science database, resulting in a sample of 3246 peer-reviewed articles published between 1980 and 2021. We combined two advanced scientometrics analysis software (i.e., CiteSpace 6.0.R1 and Gephi 0.9.2) to identify the trajectory of the literature, hotspots, and frontiers. We developed authorship-, institution-and country-levels networks to examine academic cooperation over the last forty years. Our findings revealed that the number of peer-reviewed outputs documenting the environmental effects of cover crops has consistently increased, with a notable rise in publications between 2015 and 2021. Eighteen salient research topics were identified in the literature, including winter cover crops’ effects on soil health, cover crops’ effects on nitrous oxide emissions, and the relationship between cover crops and nitrate leaching. Based on the citation-clustering analysis, the trajectory of the literature may be divided into three stages. Studies in Stage 1_A (1980–2000) mainly assessed the role of cover crops in nitrogen management. In Stage 1_B (2001–2010), the research evaluated the impact of using different cover crop mixtures on farming systems. In Stage 2 (2011–2021), studies primarily addressed the environmental impacts of cover crops, particularly their effects on physical and chemical soil properties. Finally, the countries with the most outputs were the United States, Brazil, and Spain. The U.S. Department of Agriculture-Agricultural Research Service was the main contributor to the literature on the environmental impacts of cover crops. Full article

There is one type of primary microplastic, glitter, which has not received the same attention as microbeads. The general thought associates the use of glitter with extraordinary and rare events, in reality, its presence in everyday life is much more ubiquitous than one might think. The main objective of this preliminary study was to create a mini product survey with the aim of analyzing the distribution and composition of glitter in the local market of the city of Trieste (Italy), thus creating a starting point for larger future studies. The analysis of a real context served as a snapshot for the description of the phenomenon, from which useful information was obtained: glitter is everywhere, cheap, disperses easily in the environment, is made of different materials, often has sharp-edged shapes, and mainly affects sensitive audiences, such as children. It is time to put glitter in the spotlight. Full article

Aims: Indoor air quality (IAQ) has attracted increased attention with the emergence of COVID-19. Ventilation is perhaps the area in which the most changes have been proposed in response to the emergency caused by this virus. However, other strategies are possible, such as source control and the extraction of pollutants. The latter incorporates clean technologies, an emergent area with respect to IAQ. Method: Various air treatment technologies can be used to control contaminants, which are reviewed and discussed in this work, including physicochemical technologies (e.g., filtration, adsorption, UV-photocatalytic oxidation, ultraviolet disinfection and ionization) and biological technologies (e.g., plant purification methods and microalgae-based methods). Results and interpretation: This work reviews currently available solutions and technologies for “cleaning” indoor air, with a focus on their advantages and disadvantages. One of the most common problems in this area is the emission of pollutants that are sometimes more dangerous to human health than those that the technologies were developed to remove. Another aspect to consider is the limitation of each technology in relation to the type of pollutants that need to be removed. Each of the investigated technologies works well for a family of pollutants with similar characteristics, but it is not applicable to all pollutant types. Thus, the optimal solution may involve the use of a combination of technologies to extend the scope of application, in addition to the development of new materials, for example, through the use of nanotechnology. Full article

Sustainable development and environmental issues related to ports and sea trade have highlighted the need to enhance transport and trade systems to include green practices, such as the realisation of dry ports. However, among the current studies investigating dry ports’ implications, only few papers explore their environmental impacts. Moreover, these latter papers approach the argument in a general way, leaving the ecological concerns associated with dry ports under-researched or marginally explored. In light of these premises, with the present review, the authors aim to develop a new conceptual framework on the dry ports’ environmental aspects in order to drive and support future academic research in this field. The methodology used by the authors is a systematic literature review on Scopus and Web of Science. They identified 107 relevant articles, of which 43 were included according to the authors’ propositions. The main results show that (i) there is no coordination between the various studies and systemic debates on dry ports’ environmental aspects; (ii) there are no standardised applicable tools; and (iii) there is no involvement among the various stakeholders. Additionally, a debate is also lacking under the lens of the Sustainable Development Goals of the Agenda 2030. Full article

The presence of emerging organic contaminants (EOCs) in the environment is increasing and requires the development of technologies for their effective removal. Therefore, a literature review on the behavior of EOCs during municipal wastewater treatment, both in major treatment systems and particularly in constructed wetlands (CWs), was carried out. The study also reviewed the behavior of EOCs in anaerobic digesters (ADs) and advanced oxidation processes, particularly in TiO₂-based photocatalysis, which are being proposed as promising pre- and post-treatments for combination with CW. The following ten compounds were screened: acetaminophen (ACE), ofloxacin (OFL), caffeine (CAF), carbamazepine (CBZ), ketoprofen (KET), ibuprofen (IBU), diclofenac (DCL), clofibric acid (ACB), bisphenol A (BPA), and sotalol (SOT). The degradation pathways of the selected EOCs are largely influenced by their physicochemical and biochemical properties. Sorption and biodegradation are the main elimination mechanisms found in AD and CW treatment systems, where the combination of anaerobic and aerobic environments improves the elimination efficiency of EOCs. However, various contaminants appear recalcitrant. In this sense, in combination with CWs, TiO₂-based photocatalysis emerges as a promising post-treatment for advanced EOC removal from wastewater. Full article

This metagenomics investigation of three closely adjacent sampling sites from an archaeological excavation of a pre-industrial coal mining exploration shaft provides detailed information on the composition of the local soil bacterial communities. The observed significant differences between the samples, reflected in the 16S r-RNA analyses, were consistent with the archaeologically observed situation distinguishing the coal seam, the rapidly deposited bright sediment inside an exploration shaft, and the topsoil sediment. In general, the soils were characterized by a dominance of Proteobacteria, Actinobacteria, Acidobacteria, and Archaea, whereas the coal seam was characterized by the highest proportion of Proteobacteria; the topsoil was characterized by very high proportions of Archaea—in particular, Nitrosotaleaceae—and Acidobacteria, mainly of Subgroup 2. Interestingly, the samples of the fast-deposited bright sediment showed a rank function of OTU abundances with disproportional values in the lower abundance range. This could be interpreted as a reflection of the rapid redeposition of soil material during the refilling of the exploration shaft in the composition of the soil bacterial community. This interpretation is supported by the observation of a comparatively high proportion of reads relating to bacteria known to be alkaliphilic in this soil material. In summary, these investigations confirm that metagenomic analyses of soil material from archaeological excavations can provide valuable information about the local soil bacterial communities and the historical human impacts on them. Full article

Currently, the seashore is threatened by the environment of climate change and increasing coastal waste. The past environmental groups used a large amount of manpower to manage the coast to maintain the seashore environment. The computational time cost and efficiency are not ideal for the vast area of the seashore. With the progress of GIS (Geographic Information System) technology, the ability of remote sensing technology can capture a wide range of data in a short period. This research is based on the application of remote sensing technology combined with machine learning to display the observation of our seashore. However, in the process of image classification, the seashore wastes are small, which required the use of high-resolution image data. Thus, how to remove the noise becomes a crucial issue in developing an image classifier machine. The difficulties include how to adjust the value of parameters for removing/avoiding noises. First, the texture information and vegetation indices were employed as ancillary information in our image classification. On the other hand, auto-encoder is a very good tool to denoise a given image; hence, it is used to transform high-resolution images by considering ancillary information to extract attributes. Multi-layer perceptron (MLP) and support vector machine (SVM) were compared for classifier performance in a parallel study. The overall accuracy is about 85.5% and 83.9% for MLP and SVM, respectively. If the AE is applied for preprocessing, the overall accuracy is increased by about 10–12%. Full article

The essential roles of Fe oxides in stabilizing long-term soil organic carbon (SOC), especially aromatic dissolved organic carbon (DOC_aro), are well-established in forest soils and sediments. We chose to focus on these processes in agricultural soils in which the input and translocation of native DOC to deeper soils are impacted by management practices. We quantified SOC, Fe oxide bound SOC (Fe-bound OC), and the DOC_aro sorption in a forest, a cropland, and a pasture soil at 0–10 and 10–25 cm. Significantly larger amounts of Fe oxides in the cropland soil were observed compared to the forest and pasture soils at both depths (p < 0.05). Land management practices and depth both significantly influenced the Fe-bound OC percentage (p < 0.05). Larger maximum sorptions of DOC in the cropland (315.0 mg kg⁻¹) and pasture (395.0 mg kg⁻¹) soils than the forest soil (96.6 mg kg⁻¹) at 10–25 cm weres found. DOC_aro sorption decreased in the three soils at 0–10 cm (slope of −0.002 to −0.014 L² mg⁻² m⁻¹) as well as the forest soil at 10–25 cm (−0.016 L² mg⁻² m⁻¹) with increasing equilibrium DOC concentration. Conversely, the cropland and pasture soils at 10–25 cm increased (0.012 to 0.014 L² mg⁻² m⁻¹). The different sorption behaviors of DOC_aro in these surface soils indicate that the forest, cropland, and pasture-managed soils may have more complex and various sorption behaviors in stabilizing DOC_aro and non-DOC_aro. Full article

The Paris Climate Agreement (PA) provides an overall target which limits global warming to “well below 2 °C above pre-industrial levels” and “pursuing efforts to limit the temperature increase to 1.5 °C above pre-industrial levels” (Art. 2 para. 1 PA). This article assesses the extent to which new insights can be derived from recent IPCC reports for the interpretation of Art. 2 para. 1 PA from a legal perspective. To this end, the article analyses the contributions of Working Groups I and III of the sixth assessment report. Methodologically, we compare the findings with previously published IPCC reports, namely the 1.5 °C report and the fifth assessment report. A legal interpretation of the Paris Agreement and of core concepts of human rights follows. Several empirical indications show that current global greenhouse gas budget calculations are quite generous. We provide five empirical arguments that clearly point in that direction. These empirical arguments, combined with legal arguments, demonstrate that the budgets must be smaller than those estimated by the IPCC. The legal arguments are based on Art. 2 of the Paris Agreement, as well as on human rights and the precautionary principle. These norms contain an obligation to minimise the risk of significant damage, i.e., to take rapid and drastic climate protection measures. This implies: 1.5 °C is the legally binding temperature target; adherence requires a very high probability of achieving the target; temperature overshoot and geoengineering tend to be prohibited, and budget calculations must be based on sceptical factual assumptions. These findings have also been confirmed by recent rulings of supreme courts, such as the ground-breaking climate decision of the German Federal Constitutional Court. The Paris Agreement and human rights underline a legally binding obligation for smaller global greenhouse gas budgets as those estimated in the greenhouse gas budgets of the IPCC—even compared to the 83 percent scenario in the latest assessment. Thus, climate policy will have to raise its ambitions towards zero fossil fuels and a drastic reduction of livestock farming in times of the Ukraine war. Full article

Sales of low-calorie sweeteners are increasing in the Unites States, with sucralose representing the second largest of the U.S. market share. Since >99% of ingested sucralose is excreted as the parent compound, it represents a contaminant of emerging concern and has been proposed as an indicator of pollution of natural waters by anthropogenic waste. Many report that it is increasingly omnipresent in surface, coastal, and drinking water. Given the increasing consumption of low-calorie sweeteners, changes in influent and effluent sucralose concentrations presage their concentrations in natural waters. The aim of this research was to quantify sucralose at a constructed treatment wetland that was designed to remove nutrients (nitrogen and phosphorus) from secondary treated wastewater. We report the concentrations of sucralose in the surface water, sediment, and porewater throughout the flow train of the wetlands over a period of three years and include surface water sampling following an extreme weather event. The average influent surface water concentration of sucralose was 24 ± 2 ppb, and the average outfall concentration was 20 ± 6 ppb, indicating the sucralose is not subjected to chemical or physical adsorption in the sediment within the wetland. Full article

In addition to the numerous health effects caused by the COVID-19 pandemic, the scientific community has considered other emerging effects such as water-related impacts worthy of deep investigation. In this regard, the transmission cycles of the SARS-CoV-2 virus from fecal, vomiting, and sputum routes to sewage have led health authorities to diagnose, prevent, and use novel wastewater treatment technologies. Once they enter the gastrointestinal canal of a healthy person, viral particles can infect via the nominal amount of Angiotensin-Converting Enzyme 2 (ACE2) present in alimentary canal epithelial cell surfaces and further infect lung, heart, kidney, and other organs. The current review highlights the detection, status, and fate of SARS-CoV-2 from sewage treatment facilities to water bodies. Besides, it addresses the potential wastewater treatment processes to cope with various viruses, especially SARS-CoV-2. Many processes can manage contaminated wastewater and solid wastes over the long term, including membrane technologies, disinfectants, UV-light and advanced oxidation methods like photocatalysis, ozonation, hydrogen peroxide, nanomaterials, and algae. Future work must focus on implementing the selected actions for the treatment of the wastewater released from the COVID-19 hospitals and self-quarantine centers to better regulate future waves of SARS-CoV-2. Full article

The transition of natural landscapes to agricultural uses has resulted in severe loss of soil organic carbon, significantly contributing to CO₂ emissions and rising global temperatures. However, soil has the largest store of terrestrial carbon (C), a considerable sink and effective strategy for climate change mitigation if managed properly. Cover crops (CC) and no-till (NT) management are two management strategies that are known to increase percent organic carbon (%OC); however, adoption of these practices has been low in the mid-South due to lack of region-specific research and resistance to unproven practices. Therefore, the purpose of this study was to evaluate the impacts of CC-NT treatments in soybean cropping systems on soil percent organic carbon (%OC) and CO₂ flux following long-term implementation. Results showed significantly greater %OC in NT (1.27% ± 0.03) than reduced till (RT; 1.10% ± 0.03; p < 0.001) and greater in both CC (rye: 1.23% ± 0.03, rye + clover: 1.22% ± 0.03) than no cover (1.11% ± 0.03; p < 0.001). Bacterial abundance (p = 0.005) and pH (p = 0.006) were significant predictors of %OC. There was no overall significant difference in CO₂ flux between tillage or CC treatments; however, there were significant differences between NT and RT in July of 2020 when %RH increased (p < 0.001). Bacterial abundance negatively impacted CO₂ flux (p < 0.05), which contradicts most studies. The rate of proportional change and pattern of variability in C pools suggested loss of %OC in RT treatments that were not apparent when considering %OC alone. The results of this study provide valuable insight into C turnover and the effectiveness of CC use in the Mid-South to increase soil C stocks. Full article

The environmental concerns are behind urban and regional mobility plans, with one of the goals being to manage surface traffic to reduce emissions. Yet, in sensitive areas such as those around airports, the contribution to the emissions generated by air traffic are commonly not considered. The research goal of this paper is to quantify and compare the magnitude of the emissions generated by both air and surface traffic, taking the second airport in Rome as an example, in the awareness that a proper knowledge of the emission phenomena might help steer local transport policies towards more appropriate and sustainable solutions. The paper describes the case study’s regulatory and land use frameworks both affecting the current traffic patterns around the airport and the emission generation, along with the methodology adopted to quantify the emission magnitude of both air and surface modes; as a result, air traffic emissions are not even comparable in magnitude to those from surface modes. In light of that, implications for surface transport policies are presented, leading to a revision of current mobility plans, and solutions to minimize emissions during land and take-off operations suggested, although problems for their implementations are acknowledged in the conclusions. All within the additional goal to advance the research further afield. Full article