High Levels Of Degradation Research Articles

Planetary Health: a public health answer to climate change and other Anthropocene challenges

Abstract Although in the last century, humanity achieved extraordinary outcomes in terms of health, social and economic improvements, the Earth ecosystems around us suffer of high levels of degradation. This issue poses our recent public health and development gains at risk. The Anthropocene, a new geological era we are living in since mid 20th century, is indeed characterized by humanity’s dramatic impact on Earth’s biophysical conditions. Planetary Health is a relatively new field, oriented to solutions, based on transdisciplinarity and social movement, focused on analyzing and addressing the impacts of human disruptions to Earth’s natural systems on human health and all life on Earth. In this presentation, a brief overview of the main issues related to the Anthropocene in the public health perspective will be provided and new tools for the analysis of planetary health challenges will be proposed, citing relevant case studies for discussion.

Bending the curve of global freshwater biodiversity loss: what are the prospects?

Freshwater biodiversity conservation has received substantial attention in the scientific literature and is finally being recognized in policy frameworks such as the Global Biodiversity Framework and its associated targets for 2030. This is important progress. Nonetheless, freshwater species continue to be confronted with high levels of imperilment and widespread ecosystem degradation. An Emergency Recovery Plan (ERP) proposed in 2020 comprises six measures intended to "bend the curve" of freshwater biodiversity loss, if they are widely adopted and adequately supported. We review evidence suggesting that the combined intensity of persistent and emerging threats to freshwater biodiversity has become so serious that current and projected efforts to preserve, protect and restore inland-water ecosystems may be insufficient to avert substantial biodiversity losses in the coming decades. In particular, climate change, with its complex and harmful impacts, will frustrate attempts to prevent biodiversity losses from freshwater ecosystems already affected by multiple threats. Interactions among these threats will limit recovery of populations and exacerbate declines resulting in local or even global extinctions, especially among low-viability populations in degraded or fragmented ecosystems. In addition to impediments represented by climate change, we identify several other areas where the absolute scarcity of fresh water, inadequate scientific information or predictive capacity, and a widespread failure to mitigate anthropogenic stressors, are liable to set limits on the recovery of freshwater biodiversity. Implementation of the ERP rapidly and at scale through many widely dispersed local actions focused on regions of high freshwater biodiversity and intense threat, together with an intensification of ex-situ conservation efforts, will be necessary to preserve native freshwater biodiversity during an increasingly uncertain climatic future in which poorly understood, emergent and interacting threats have become more influential. But implementation of the ERP must be accompanied by measures that will improve water, energy and food security for humans - without further compromising the condition of freshwater ecosystems. Unfortunately, the inadequate political implementation of policies to arrest widely recognized environmental challenges such as climate change do not inspire confidence about the possible success of the ERP. In many parts of the world, the Anthropocene future seems certain to include extended periods with an absolute scarcity of uncontaminated surface runoff that will inevitably be appropriated by humans. Unless there is a step-change in societal awareness of - and commitment to - the conservation of freshwater biodiversity, together with necessary actions to arrest climate change, implementation of established methods for protecting freshwater biodiversity may not bend the curve enough to prevent continued ecosystem degradation and species loss.

Effects of grassland degradation on diversity of arbuscular mycorrhizal fungi of a pioneer plant.

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts that engage in crucial interactions with plants, playing a vital role in grassland ecology. Our study focuses on the pioneer plant Agropyron cristatum, and we collected soil samples from four degraded grasslands in Yudaokou to investigate the response of community composition to the succession of degraded grasslands. We measured the vegetation status, soil physical and chemical properties, AMF colonization, and spore density in different degraded grasslands. High-throughput sequencing was employed to analyze AMF in soil samples. Correlations among community composition, soil characteristics, and plant factors were studied using principal component and regression analyses. The distribution of AMF in grasslands exhibited variation with different degrees of degradation, with Glomus, Scutellospora, and Diversispora being the dominant genera. The abundance of dominant genera in AMF also varied, showing a gradual increase in the relative abundance of the genus Diversispora with higher degradation levels. AMF diversity decreased from 27.7% to 12.4% throughout the degradation process. Among 180 samples of Agropyron cristatum plants, AMF hyphae and vesicles displayed the highest infection status in non-degraded grasslands and the lowest in severely degraded ones. Peak AMF spore production occurred in August, with maximum values in the 0-10-cm soil layer, and the highest spore densities were found in lightly degraded grasslands. Apart from pH, soil factors exhibited a positive correlation with AMF infection during grassland degradation. Furthermore, changes in AMF community composition were jointly driven by vegetation and soil characteristics, with vegetation coverage and soil organic carbon significantly impacting AMF distribution. Significant differences in AMF variables (spore number and diversity index) were also observed at different soil depths. Grassland successional degradation significantly influences AMF community structure and composition. Our future focus will be on understanding response mechanisms and implementing improvement methods for AMF during grassland degradation and subsequent restoration efforts.

Hydromorphological degradation modifies long-term macroinvertebrate responses to water quality and climate changes in lowland rivers

Due to decades of persistent anthropogenic pressures, lowland rivers represent one of the most severely impaired habitats in Europe. Despite improved water quality, novel stressors, particularly climate change, are emerging with most lowland rivers suffering from past hydromorphological degradation. We aim to elucidate how such degradation alters the biological response in multiple-stressor environments, as this has rarely been considered in studies documenting long-term development of anthropogenically impacted rivers. Here, benthic macroinvertebrates, water quality and hydroclimatic variables were monitored over a period of two decades in nine of the largest Czech rivers. Detailed data on hydromorphological degradation allowed us to track distinct patterns in rivers with high and low levels of degradation. Temporal changes in environmental variables showed similar patterns in both site groups, characterised by reduced organic and nutrient pollution but increased hydroclimatic and salinity stress. 150 % increase in total abundance, especially in abundance and richness of sediment-dwelling and non-native taxa was found in both site groups. While the increase in abundance was due to improved water quality and rising water temperature, the longer duration of minimal flows had a negative effect on species richness, hampering species gain particularly at highly degraded sites. Our results provide novel evidence that degree of hydromorphological degradation modifies long-term macroinvertebrate responses to anthropogenic pressures. Less degraded sites displayed several favourable changes, such as 27 % increase in total and 23 % increase in potamal indicator richness, and stabilisation of the assemblages with few functional changes. In contrast, highly degraded sites experienced 9 % reduction in evenness, 235 % increase in proportion of non-native taxa and functional reorganisation, changes congruent with continuous deterioration. While overall water quality at studied sites has improved, consequences of climate change and high degree of hydromorphological degradation limit biotic recovery in multiple-stressor lowland rivers.

MRNA-encoded Cas13 treatment of Influenza via site-specific degradation of genomic RNA.

The CRISPR-Cas13 system has been proposed as an alternative treatment of viral infections. However, for this approach to be adopted as an antiviral, it must be optimized until levels of efficacy rival or exceed the performance of conventional approaches. To take steps toward this goal, we evaluated the influenza viral RNA degradation patterns resulting from the binding and enzymatic activity of mRNA-encoded LbuCas13a and two crRNAs from a prior study, targeting PB2 genomic and messenger RNA. We found that the genome targeting guide has the potential for significantly higher potency than originally detected, because degradation of the genomic RNA is not uniform across the PB2 segment, but it is augmented in proximity to the Cas13 binding site. The PB2 genome targeting guide exhibited high levels (>1 log) of RNA degradation when delivered 24 hours post-infection in vitro and maintained that level of degradation over time, with increasing multiplicity of infection (MOI), and across modern influenza H1N1 and H3N2 strains. Chemical modifications to guides with potent LbuCas13a function, resulted in nebulizer delivered efficacy (>1-2 log reduction in viral titer) in a hamster model of influenza (Influenza A/H1N1/California/04/09) infection given prophylactically or as a treatment (post-infection). Maximum efficacy was achieved with two doses, when administered both pre- and post-infection. This work provides evidence that mRNA-encoded Cas13a can effectively mitigate Influenza A infections opening the door to the development of a programmable approach to treating multiple respiratory infections.

Impact of Urbanization Processes on Vegetation Cover in the Cities Over the Last Two Decades

Background: The process of urbanization serves as a prominent factor leading to the vegetation cover decline in major cities worldwide. This issue has significant consequences for the living environment on a global scale. Methods: Leveraging the latest advancements in remote sensing techniques (RSTs) and utilizing high-resolution satellite imagery, this study aims to assess the vegetation cover alteration (VCA) in correlation with the urbanization process in Thai Nguyen City, Vietnam. Landsat 5 TM and Sentinel 2A satellite imagery were used to analyze the VCA in Thai Nguyen City during the period from 2001 to 2023. Thai Nguyen city is recognized as the third largest in Northern Vietnam, following the capital city of Hanoi and Hai Phong City and ranks as the tenth most populous city in Vietnam. Result: The results obtained from this study demonstrate a substantial overall expansion, with the total urban land increasing from 386 hectares in 2001 to 1045 hectares in 2010 and experiencing a rapid surge in 2023, reaching a remarkable 4409 hectares. In general, analyzed results based on VCA maps indicated an overall vegetation cover reduction across the study area. This indicates that the study area has reached a critically high level of degradation in terms of vegetation cover. These findings emphasize the escalating risks associated with the diminishing vegetation cover detected across the study area.

Can a naturally depauperate Ephemeroptera, Plectoptera and Trichoptera (EPT) fauna track river degradation in south-western Australia?

Freshwater aquatic ecosystems are threatened globally. Biological monitoring is required to deliver rapid and replicable assessment of changes in habitat quality. The Ephemeroptera, Plectoptera, Trichoptera (EPT) index is a globally recognised rapid bioassessment that measures taxa richness of three insect orders whose larvae are considered sensitive to freshwater habitat degradation. South-western Australia contains threatened freshwater ecosystems but has depauperate EPT fauna and high endemism, potentially reducing the capacity of the EPT index to track degradation. This study investigated if EPT species richness, composition or individual species tracked physical or chemical river degradation in three catchments in south-western Australia. We sampled EPT fauna and measured water chemistry, erosion, sedimentation, riparian vegetation cover and instream habitat at 98 sites in the winters of 2007 and 2023. We found 35 EPT taxa across the study area with a median number of species per site of two. EPT species richness had weak positive associations with a composite water quality index and dissolved oxygen and weak negative associations with electrical conductivity and total nitrogen. No association was found between physical and fringing zone degradation measures and EPT species richness. EPT community structure generally did not distinguish between sites with high or low degradation levels. The presence of the mayfly Nyungara bunni tracked salinity, dissolved oxygen and nitrogen levels, but its usefulness as a bioindicator could be limited by its restricted range. This study suggests that the EPT index would need modification or combination with other indices to be a useful rapid bioassessment in south-western Australia.

Potential Role of Bioactive Compounds: In Vitro Evaluation of the Antioxidant and Antimicrobial Activity of Fermented Milk Thistle

The group of innovative ingredients in cosmetic preparations includes bio-ferments (Bs), which are characterized by high bioactivity and biocompatibility, and one of the plants rich in bioactive compounds that has a beneficial effect on the skin and the body is Silybum marianum. Bio-ferments obtained from this plant are becoming increasingly useful as active ingredients in cosmetics. In the present study, four different bio-ferments were obtained by fermentation of pomace (B-P), extract (B-E), oil (B-O), and seeds (B-S) of milk thistle. Their biodegradability (%B), total polyphenols content (Folin–Ciocalteu method), and antimicrobial, antioxidant (DPPH, ABTS, and FRAP methods), chelating (Fe2+ ions), and reduction (Cu2+ and Fe3+ ions) properties, as well as the acidity, were evaluated. The contact angle using the sessile drop method was assessed to investigate bio-ferments’ impact on skin wettability. Finally, the content of selected phenolic acids in the Bs was evaluated using the HPLC method, while the lactic acid (LA) content was assessed using the GC-MS method. All bio-ferments were characterized by high polyphenols content (13.56 ± 0.10–15.28 ± 0.12 mmol GA/L B), chelating (0.08 ± 0.01–0.17 ± 0.01 mmol Fe2+/L B) and antioxidant activity (DPPH method, 2.41 ± 0.01–3.53 ± 0.01 mmol Tx/L B), and reducing Cu2+ and Fe3+ ions. Gallic acid, protocatechuic acid, caffeic acid, neochlorogenic acid, coumaric acid, and LA were identified in Bs. The most increased antibacterial activity for B-P was observed for a strain of Staphylococcus aureus (MIC = 250 μL/mL) and Pseudomonas aeruginosa (MIC = 250 μL/mL). Simultaneously, B-S demonstrated the highest inhibitory effects against Escherichia coli (MIC = 125 μL/mL), emphasizing the varied antimicrobial profiles of these bio-ferments against different bacterial strains. Research on aerobic biodegradation demonstrated a high level of degradation (%B = 60 ± 1–65 ± 3), and all Bs were categorized as readily degradable according to the OECD classification.

Synthesis of two TiO2-based prodegradant additives and their efficiency in inducing the accelerated photo-oxidation of low-density polyethylene

In this study, two prodegradant additives derived from TiO2 nanoparticles were synthesized and comprehensively characterized through a range of analytic techniques, such as X-ray diffraction (DRX), Fourier Transform Infrared Spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The hydroxyl groups adsorbed on the surface of TiO2 were esterified with biobased arachidonic acid (AA) and cervonic acid (DHA), resulting in levels of functionalization at 13 % and 16 % w/w, respectively. These additives were incorporated into low-density polyethylene (LDPE) films, at concentrations of 1 % and 3 % w/w. The prodegradant efficiency of the additives was subsequently assessed through accelerated UV aging. Following 200 h of exposure, the aged films experienced a loss in molecular weight (Mw) by approximately 95 %, accompanied by carbonyl indexes (CI) measuring 1.8 and 2.0. This high level of degradation observed in the LDPE films denotes an effective degradation mechanism, reliant on the generation of hydroxyl radicals by the TiO2 moiety, upon UV light exposure, and the subsequent abstraction of labile hydrogens within the polyunsaturated sidechain of the additives, resulting in the formation of peroxyl radicals, thereby initiating the swift auto-oxidation of the polyethylene films.

Состояние почвенного покрова и фитомелиорация пастбищ в районах Восточного Предкавказья

Introduction. The arid zone of the Eastern Ciscaucasia, and specifically the extremely arid and arid areas of the Stavropol Territory, with low-fertile pasture soil cover, are subject to degradation associated with both soil and climatic conditions and anthropogenic technological load on the soil. Materials and methods. The manifestation and areas occupied by soil degradation factors (the presence of salt marshes, salt marshes, erosion and deflation) in each of the districts are different, therefore, for a comprehensive assessment of the level of degradation in a particular area, calculations of the generalized indicator of degradation of the soil cover of pastures are carried out. Results and discussion. Based on a systematic analysis, with an assessment of the desirability and weight of each of the degradation factors, it was found that the soil cover of the pastures of the Kursk region is subject to a moderate level of degradation (Dp=0.95), Ipatovsky district with Dp=0.90 – increased, and Apanasenkovsky Turkmen, Arzgir, Levokumsky, Neftekumsky districts – a high level of degradation with Dp=0.822–0.828. Сonclusion. In an area with a moderate level of degradation of the pasture soil cover, a superficial improvement of the natural herbage is proposed with the addition of perennial grasses to it: Medicagovaria, Melilotusofficinalis, Melilotus album, Agropyron fragile, Kochiaarenaria. With an increased and high level of degradation of pasture soils, it is advisable to radically improve with the use of legume-cereal grass mixtures from Medicagofalcata, Medicagovaria, Onobrychisarenaria, Agropyron fragile, Elytrigiaintermedia, Bromopsisinermis, Kochiaarenaria. On saline soils, it is also effective to use both Medicago falcate and Medicagovaria and Agropyrondesertorum, Agropyroncristatum, Elytrigiaintermedia, Bromopsisinermis, Kochiaarenaria, Bassiaprostrata, Melilotusofficinalis, Melilotus album, Festucavalesiaca, Leymusracemosus. Suggestions for practical application and direction of future research. The developed map-scheme of degradation of the soil cover of pastures of the Stavropol Territory districts, indicating the numerical values of the complex indicator Dp, allows you to make certain technological decisions on carrying out a complex of phyto-meliorative measures on pastures specifically for each district of the Eastern Caucasus.

Soil physical properties as indicators of histosol degradation in Colombia

Changes in soil utilization exert detrimental effects on its properties, emphasizing the critical need for a thorough evaluation to mitigate their repercussions on the ecosystem. This investigation was conducted aiming to assess the physical degradation in histosol soils in the Putumayo department, Colombia, caused by alterations in land use. For this, we assessed two types of areas: those without intervention (T0) and those affected by deformation in mound structures caused by the combined actions of livestock and high moisture, commonly known as “tatucos”. The assessment categorized these areas based on the percentage deformation incidence: low degradation (T1), moderate degradation (T2), and high degradation (T3). Sampling was conducted at a depth of 15 cm, both in the tatuco-affected zone and its surrounding area. Measurements were taken for mound height and diameter, as well as physical properties such as bulk and real density, porosity, volumetric moisture, penetration resistance, and the degree of organic material decomposition. The primary land use identified in the study area was extensive livestock farming. It was established that in areas with high levels of degradation (T3), there was an average mound diameter of 151.9 ± 4.46 cm and a height of 22.7 ± 2.59 cm. Regarding physical properties in the area adjacent to the mound, there was a bulk density of 0.24 g.cm-3, a real density of 1.62 g.cm-3, and a penetration resistance of 0.71 MPa. These values were significantly higher than those observed in areas without intervention. Hence, it can be inferred that the alteration in land use is causing a substantial change in the physical properties of these soils, which are vital for the agroecosystems in the southern regions of Colombia.

Characterization of non-invasive oropharyngeal samples and nucleic acid isolation for molecular diagnostics

Molecular diagnostics is an increasingly important clinical tool, especially in routine sampling. We evaluated two non-invasive methods (oral swabs and mouthwashes) for sampling nucleic acids from the oral/pharyngeal area. We created a workflow from sample collection (n = 59) to RT-qPCR based analysis. The samples were further characterized in terms of their cellular composition as well as the purity, degradation and microbial content of the derived DNA/RNA. We determined the optimal housekeeping genes applicable for these types of samples. The cellular composition indicated that mouthwashes contained more immune cells and bacteria. Even though the protocol was not specifically optimized to extract bacterial RNA it was possible to derive microbial RNA, from both sampling methods. Optimizing the protocol allowed us to generate stable quantities of DNA/RNA. DNA/RNA purity parameters were not significantly different between the two sampling methods. Even though integrity analysis demonstrated a high level of degradation of RNA, corresponding parameters confirmed their sequencing potential. RT-qPCR analysis determined TATA-Box Binding Protein as the most favorable housekeeping gene. In summary, we have developed a robust method suitable for multiple downstream diagnostic techniques. This protocol can be used as a foundation for further research endeavors focusing on developing molecular diagnostics for the oropharyngeal cavity.

The surge for local innovative institutions for transformation: community-based monitoring in the Andes

Abstract Non-technical summary There is abundant research about the impacts that large-scale mining produces on territories to the detriment of their social and environmental sustainability. However, during our research in Chile and Peru, we also identified local transformative initiatives that pursue sustainable development by proposing alternatives to how the socio-ecological impacts of natural resource extraction are produced and distributed throughout society. Specifically, we ask the question: How do local communities in Chile and Peru that are affected by mining activities engage in community-based environmental monitoring (CBEM)? Technical summary By examining how local communities in Chile and Peru engage in community environmental monitoring, this paper argues that local political organisation and institutional innovations are crucial for the emergence of transformations towards sustainability. Local political organisation and mobilisation can create a window of opportunity for discussion about extractive activities and their impacts, as well as possible proposals for alternatives. Institutional innovations triggered by local political work can lead to the implementation of such initiatives. Our findings are based on qualitative case studies of CBEM in Chile and Peru, in areas with high levels of environmental degradation due to mining. In Chile we analysed a case of community air monitoring in a copper processing area, and in Peru a case of community water monitoring in a mining area. Drawing on debates on social transformation and political ecology theory, this study aims to show CBEM promotes changes towards a more democratic and preventive environmental governance, and encourages the recognition of environmental injustices. Social media summary This paper analyses how local communities in Chile and Peru engage in community environmental monitoring in areas affected by the presence of extractive industries. We identified local transformative initiatives that pursue sustainable development by proposing alternatives to how the socio-environmental impacts of natural resource extraction are produced and distributed in society. Our findings are based on qualitative case studies of community-based air and water monitoring in extractive areas in Chile and Peru.

Widespread degradation and limited protection of forests in global tropical dry ecosystems

Despite their ecological and socioeconomic importance, the forested areas of tropical dry ecosystems remain among the most threatened biomes worldwide. There has been limited research on the current extent, fragmentation, and conservation status of tropical dry forests on a global scale. In this study, we used the GLAD UMD Forest Height dataset to provide a high-resolution global assessment of the extent, patch size distribution, and protection levels of Tropical and Subtropical Dry Broadleaf Forests (TBDF) and forested areas of the Tropical and Subtropical Grasslands, Savannas, and Shrublands (TSGSS) by ecoregion and country. We find that despite increasing protection, degradation continues to rise with less than ⅓ of the original TBDF and TSGSS currently forested and over 80 % of those forests currently exposed to edge effects. <1 % of the remaining forest patches are large (>10 km2), and <25 % of the remaining forests are located in conservation or protection zones (TBDF:16 %; TSGSS:21 %), with a heavy protection bias in S.E. Asia. These results indicate high levels of degradation and low conservation leading to potentially severe ecological consequences. Systematic and coordinated efforts are needed to reduce the pressure on this ecosystem and ensure the ongoing provisioning of biodiversity and ecosystem services in these ecoregions.

Monitoring the Degradation of Semi-Natural Grassland Associations under Different Land-Use Patterns

The topicality of our research topic is justified by the significant change in traditional grassland management in the grassland areas of the Pannonian Basin. Due to several factors, the proportion of fallow grassland, and in parallel of over-exploited pastures, is continuously increasing. In the medium term (11 years), the effects of fallowing (Z), annual mowing (M), mowing and grazing (meadow treatment M + G), and permanent overgrazing (OG) as treatments on the population structure of grassland plants were investigated in a semi-natural grassland community in the Solonyec soil. It was found that the lowest degradation rates in the studied grassland biotope were obtained for the treatment presenting the utilisation pattern of mowing the main grassland phytomass followed by sheep grazing of the coltgrass. The highest degradation levels, which threatened the condition of the grassland community, were measured for the treatment presenting overgrazing with sheep at the end of the experimental period.

Degradation of Soil Quality Related Physical and Chemical Properties Affected by Agricultural Practice in Le Thuy District, Quang Binh Province, Vietnam

Background: Agricultural practice is considered as main factor affecting land degradation in several regions in Vietnam. However, there are limited studies relating to degraded soil properties and their soil fertility. This paper aimed to evaluate the degradation of agricultural soil under different land management practices. Methods: A total of 80 samples at 0-10 cm of agricultural soil were collected to analyze selected physicochemical properties. The group of degradation soil properties was classified based on their soil fertility using principal component analysis. Result: The results showed that physicochemical properties in agricultural soil along coastal regions were relatively lower than in hilly regions/secondary forests. High ratio of C:N in agricultural soil was because of degradation. The organic matter, nitrogen and phosphorous contents were low in the soil in lowland areas indicating a high level of degradation (1.43%, 0.09% and 0,04%, respectively). The samples classified into four groups (G1, G2, G3, G4) using principal component analysis indicated differences in soil properties due to degradation. Insufficient and excessive application of inorganic fertilizer could be a further reason affecting the status of soil properties. Overall, soil physicochemical properties indicated poor conditions for agriculture systems, thereby, careful soil management is the primary solution.

Reforestation in The Reclamation Area of Pongkor Gold Mining

Ex-mining land is categorized as land with a high level of degradation. The loss of biodiversity, low soil fertility, loss of several layers of soil horizons, unbalanced texture, and even contamination can occur due to mining activities. Reforestation of mining land has been carried out with the approaches of improving the physical properties of the soil, selecting plant types, and improving soil biology in ex-gold mining land in Bogor. The addition of compost significantly increased organic matter content, C/N ratio, macronutrients (N, P, K) content, and improved soil texture. The application of Mycorrhiza and Rhizobium significantly increased the growth of forest plants such as trembesi (Samanea saman), gmelina (Anthocepalus cadamba), and ganitri (Elaeocarpus angustifolus) in ex-gold mining areas. Applying that significantly improved vegetation diversity on ex-gold mining land, including more than eight types of understory plants, and more than five plants were from the trees group. The result showed that reforestation of ex-mining land was feasible if it was carried out with a comprehensive approach.

Comprehensive assessment of degradation and methods of phytomelioration of low-yielding soils of the Volga region

In the Volgograd Region, more than 3.9 million hectares of agricultural land, including 2.1 million hectares of arable land (36%), and 1.8 million hectares of hayfields and pastures (64%), are subject to degradation and desertification to one degree or another. The article presents the results of a survey of the Trans-Volga region, by the percentage ratio of areas of low-yielding soils subject to degrading factors and calculations of a complex indicator of soil Dр. It was found that the low-productive lands of the Bykovsky district are subject to a moderate level of degradation (Dp = 0.94). An increased level of soil degradation was noted in the Mykolaiv and Staropoltavsky districts with a Dp equal to 0.91 and 0.89. A high level of degradation was detected in the Leninsky, Pallasovsky and Sredneakhtubinsky districts with Dp equal to 0.87, 0.86 and 0.83, respectively. In areas with a moderate level of degradation, a set of measures with superficial improvement is proposed. With an increased and high level of degradation, it is proposed to use root and surface improvement with the use of drought-resistant and halophytic vegetation. The results of calculations of the complex, indicator of the degree of degradation of low-yielding lands of the Volga region and the proposed methods of phytomelioration are the basis for making tactical decisions to reduce the impact of degradation factors on the soil.

Two in one is really better: NiAl-LDH/[CoNi(μ3-tp)2(μ2-py)2] nanocomposite for enhanced antibiotic norfloxacin degradation and H2 evolution reaction

As an astonishing way of dealing with both environmental pollution and the energy crisis, we report the synthesis of a remarkable nanocomposite comprising Co-Ni-based metal–organic framework [CoNi(μ3-tp)2(μ2-py)2 or CNTP-MOF] allied with Ni-Al-based layered double hydroxide (NiAl-LDH) via a facile thermal impregnation technique. It showed outstanding degradation of norfloxacin and renewable H2 evolution under simulated solar light irradiation. Notably, the photocatalytic performance of NiAl-LDH/CNTP-MOF nanocomposite was significantly improved compared to its two individual components, reaching a high norfloxacin degradation level of 96 % in 60 min and H2 evolution of around 1914 µmol g−1 within 5 h of irradiation time. In addition, four successive photocatalytic cycles using the NiAl-LDH/CNTP-MOF nanocomposite revealed that our synthesized material has extremely excellent stability without affecting the morphological structure. Potential reaction routes for norfloxacin degradation and H2 evolution over the most active NiAl-LDH/CNTP-MOF nanocomposite are also discussed in detail, wherein the heterojunction plays a key role in the enhancement of electron-hole pair separation, consequently substantial efficiency. Eventually, this work provides excellent insights for designing and constructing MOF-based nanocomposite with notable photocatalytic performance toward wide-ranging environmental remediation.

Auto-combustion designed BiFeO3/Bi2O3 photocatalyst for improved photodegradation of nitrobenzene under visible light and sunlight irradiation

Herein, using the auto-combustion method, a BiFeO3/Bi2O3 composite was successfully synthesized for the photocatalytic degradation of nitrobenzene under visible illumination. The compound was subsequently characterized using varied characterization approaches, including XRD, SEM/EDS, FTIR, XPS, and UV–VIS techniques. The photocatalytic capability of the resulting sample was assessed by removing nitrobenzene (NB) under solar and artificial (15 W LED lamp) exposure. Within 180 and 240 min of exposure, the prepared BiFeO3/Bi2O3 composite exhibited impressive photocatalytic ability with quasi-total elimination (100%) of NB under both solar and LED lights, in contrast to pure oxides. The photocatalytic capability of BiFeO3/Bi2O3 was 2.88 and 1.67 folds higher than those of BiFeO3 and Bi2O3. This was linked to the effective charge splitting occurring at the BiFeO3/Bi2O3 interface and the lower recombination ratio of charge carriers. Additionally, BiFeO3/Bi2O3 exhibited outstanding sustainability without loss of activity during the first 5 cycles. Aside from this, quenching investigation showed that •OH was responsible for the degradation process. Furthermore, total organic carbon (TOC) analysis confirmed NB mineralization. Based on these previous findings, an appropriate mechanism for NB decomposition was established. Overall, the BiFeO3/Bi2O3 photocatalyst is recommended for use in the efficient photocatalytic removal of organic contaminants owing to its straightforward manufacturing approach, high levels of degradation, and strong structure for potential uses.