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1.
Environ Monit Assess ; 196(6): 566, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775858

RESUMEN

Microbial communities from freshwater sediments are involved in biogeochemical cycles and they can be modified by physical and chemical changes in the environment. Linking the microbial community structure (MCS) with physicochemistry of freshwater courses allows a better understanding of its ecology and can be useful to assess the ecological impact generated by human activity. The MCS of tributary channels from La Plata River affected by oil refinery (C, D, and E) and one also by urban discharges (C) was studied. For this purpose, 16S rRNA metabarcoding analysis, in silico metagenome functional prediction, and the hydrocarbon degradation potential (in silico predictions of hydrocarbon-degrading genes and their quantification by qPCR) of the MCS were studied. Principal coordinate analysis revealed that the MCS was different between sites, and it was not structured by the hydrocarbon content. Site C showed physicochemical characteristics, bacterial taxa, and an in silico functional prediction related to fermentative/heterotrophic metabolism. Site D, despite having higher concentration of hydrocarbon, presented autotrophic, syntrophic, and methanogenic pathways commonly involved in natural processes in anoxic sediments. Site E showed and intermediate autotrophic/heterotrophic behavior. The hydrocarbon degradation potential showed no positive correlation between the hydrocarbon-degrading genes quantified and predicted. The results suggest that the hydrocarbon concentration in the sites was not enough selection pressure to structure the bacterial community composition. Understanding which is the variable that structures the bacterial community composition is essential for monitoring and designing of sustainable management strategies for contaminated freshwater ecosystems.


Asunto(s)
Monitoreo del Ambiente , Microbiota , Ríos , Contaminantes Químicos del Agua , Ríos/microbiología , Ríos/química , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Argentina , ARN Ribosómico 16S/genética , Biodegradación Ambiental , Hidrocarburos/metabolismo , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Restauración y Remediación Ambiental/métodos
2.
Environ Sci Technol ; 58(19): 8531-8541, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38690765

RESUMEN

Colloidal activated carbon (CAC) is an emerging technology for the in situ remediation of groundwater impacted by per- and polyfluoroalkyl substances (PFAS). In assessing the long-term effectiveness of a CAC barrier, it is crucial to evaluate the potential of emplaced CAC particles to be remobilized and migrate away from the sorptive barrier. We examine the effect of two polymer stabilizers, carboxymethyl cellulose (CMC) and polydiallyldimethylammonium chloride (PolyDM), on CAC deposition and remobilization in saturated sand columns. CMC-modified CAC showed high mobility in a wide ionic strength (IS) range from 0.1 to 100 mM, which is favorable for CAC delivery at a sufficient scale. Interestingly, the mobility of PolyDM-modified CAC was high at low IS (0.1 mM) but greatly reduced at high IS (100 mM). Notably, significant remobilization (release) of deposited CMC-CAC particles occurred upon the introduction of solution with low IS following deposition at high IS. In contrast, PolyDM-CAC did not undergo any remobilization following deposition due to its favorable interactions with the quartz sand. We further elucidated the CAC deposition and remobilization behaviors by analyzing colloid-collector interactions through the application of Derjaguin-Landau-Verwey-Overbeek theory, and the inclusion of a discrete representation of charge heterogeneity on the quartz sand surface. The classical colloid filtration theory was also employed to estimate the travel distance of CAC in saturated columns. Our results underscore the roles of polymer coatings and solution chemistry in CAC transport, providing valuable guidelines for the design of in situ CAC remediation with maximized delivery efficiency and barrier longevity.


Asunto(s)
Coloides , Restauración y Remediación Ambiental , Agua Subterránea , Agua Subterránea/química , Coloides/química , Restauración y Remediación Ambiental/métodos , Polímeros/química , Carbón Orgánico/química , Arena/química , Contaminantes Químicos del Agua/química , Carbono/química
3.
Environ Monit Assess ; 196(5): 491, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691183

RESUMEN

This study explores the dual applications of a greenly synthesized ZnO@CTAB nanocomposite for the efficient remediation of Rhodamine B (RhB) and lead (Pb). The synthesis method involves a sustainable approach, emphasizing environmentally friendly practices. FT-IR, XRD, FESEM, zeta potential, and particle size analyzer (PSA), BET, and UV-VIS were used to physically characterize the zinc oxide and CTAB nanocomposite (ZnO@CTAB). The size and crystalline index of ZnO@CTAB are 77.941 nm and 63.56% respectively. The Zeta potential of ZnO@CTAB is about - 22.4 mV. The pore diameter of the ZnO@CTAB was 3.216 nm, and its total surface area was 97.42 m2/g. The mechanism of adsorption was investigated through pHZPC measurements. The nanocomposite's adsorption performance was systematically investigated through batch adsorption experiments. At pH 2, adsorbent dose of 0.025 g, and temperature 50 °C, ZnO@CTAB removed the most RhB, while at pH 6, adsorbent dose of 0.11 g, and temperature 60 °C, ZnO@CTAB removed the most Pb. With an adsorption efficiency of 214.59 mg/g and 128.86 mg/g for RhB and Pb, the Langmuir isotherm model outperforms the Freundlich isotherm model in terms of adsorption. The pseudo-2nd-order model with an R2 of 0.99 for both RhB and Pb offers a more convincing explanation of adsorption than the pseudo-1st-order model. The results demonstrated rapid adsorption kinetics and high adsorption capacities for RhB and Pb. Furthermore, there was minimal deterioration and a high reusability of ZnO@CTAB till 4 cycles were observed.


Asunto(s)
Plomo , Nanocompuestos , Rodaminas , Contaminantes Químicos del Agua , Óxido de Zinc , Plomo/química , Óxido de Zinc/química , Rodaminas/química , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Adsorción , Cetrimonio/química , Restauración y Remediación Ambiental/métodos , Tecnología Química Verde , Nanoestructuras/química
4.
Curr Biol ; 34(9): R371-R379, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714168

RESUMEN

The global restoration agenda can help solve the biodiversity extinction crisis by regenerating biodiversity-rich ecosystems, maximising conservation benefits using natural regeneration. Yet, conservation is rarely the core objective of restoration, and biodiversity is often neglected in restoration projects targeted towards carbon sequestration or enhancing ecosystem services for improved local livelihoods. Here, we synthesise evidence to show that promoting biodiversity in restoration planning and delivery is integral to delivering other long-term restoration aims, such as carbon sequestration, timber production, enhanced local farm yields, reduced soil erosion, recovered hydrological services and improved human health. For each of these restoration goals, biodiversity must be a keystone objective to the entire process. Biodiversity integration requires improved evidence and action, delivered via a socio-ecological process operating at landscape scales and backed by supportive regulations and finance. Conceiving restoration and biodiversity conservation as synergistic, mutually reinforcing partners is critical for humanity's bids to tackle the global crises of climate change, land degradation and biodiversity extinction.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Cambio Climático , Ecosistema , Restauración y Remediación Ambiental/métodos , Secuestro de Carbono
5.
Curr Biol ; 34(9): R379-R387, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714169

RESUMEN

For decades, China has implemented restoration programs on a large scale, thanks to its capacity to set policy and mobilize funding resources. An understanding of China's restoration achievements and remaining challenges will help to guide future efforts to restore 30% of its diverse ecosystems under the Kunming-Montreal Global Biodiversity Framework. Here we summarize the major transitions in China's approach to ecosystem restoration since the 1970s, with a focus on the underlying motivations for restoration, approaches to ecosystem management, and financing mechanisms. Whereas China's restoration efforts were predominantly guided by the delivery of certain ecosystem functions and services in earlier decades, more recently it has come to emphasize the restoration of biodiversity and ecosystem integrity. Accordingly, the focal ecosystems, approaches, and financing mechanisms of restoration have also been considerably diversified. This evolution is largely guided by the accumulation of scientific evidence and past experiences. We highlight the key challenges facing China's restoration efforts and propose future directions to improve restoration effectiveness, with regard to goal setting, monitoring, stakeholder involvement, adaptive management, resilience under climate change, and financing.


Asunto(s)
Biodiversidad , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , China , Conservación de los Recursos Naturales/métodos , Restauración y Remediación Ambiental/métodos
6.
Curr Biol ; 34(9): R387-R393, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714170

RESUMEN

The global decade of restoration brings into sharp focus the need to rehabilitate lands damaged by mining, to provide safe, stable, and productive landscapes. For the majority of mines, the required final land use is some form of natural, semi-natural or managed ecosystem, such as agriculture, aquaculture or forestry. Mining activities lead to new highly altered landscapes that require rehabilitation. These comprise various on-land stores of waste material and mined land itself. The repair of damaged ecosystems is described by many terms including restoration, rehabilitation, revegetation, ecological restoration, and reclamation. These terms overlap in meaning, have regional biases, and all fall short of what is really required: ecosystem reconstruction. This requires a highly multidisciplinary approach drawing on many disciplines including geotechnical engineering, social science, soil science, law, hydrology, botany, geology, pollination biology, financial planning, alongside ecology. Ideally, mine rehabilitation should be progressive, start early in the life of the mine, and employ a strict regime of characterising and tracking waste materials for use in creating safe and stable post-mining landscapes. These actions will limit risks and optimise outcomes, especially when waste materials contain toxic metals or have high levels of acidity, alkalinity or salinity. Some mine sites are appropriate for the restoration of native ecosystems and biodiversity that existed pre-mining, but many, including landscape features created from waste materials, are not. Criteria for successful land rehabilitation are complex, multivariate, and highly contingent on the agreed final land use. Future advances in mine rehabilitation include the use of geomorphic landscape design and emerging thinking on cradle-to-cradle mining. This primer will discuss the complex factors that need to be considered in ecosystem reconstruction after mining and outlines approaches for optimising land rehabilitation outcomes.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Minería , Conservación de los Recursos Naturales/métodos , Restauración y Remediación Ambiental/métodos
7.
Curr Biol ; 34(9): R356-R359, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714165

RESUMEN

The successful restoration of the river that used to be the dirtiest in Europe shows that any water course can be brought back to life. Around the world, different approaches and different goals are being pursued in a multitude of river restoration projects, with barrier removals showing a growing trend.


Asunto(s)
Ríos , Europa (Continente) , Conservación de los Recursos Naturales/métodos , Restauración y Remediación Ambiental/métodos
8.
Curr Biol ; 34(9): R412-R417, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714174

RESUMEN

The global community has outlined ambitious ecosystem restoration targets. Yet implementation is slow, and a lack of funding is a key barrier to upscaling restoration activities. Most restoration projects are funded by public institutions and recent high-level initiatives have emphasised the need to scale private finance in restoration. Private finance can be channelled into restoration through various financial mechanisms but is held back by a lack of return-making investment opportunities. Various institutions have now been created to commodify previously non-market ecosystem services and make them investable, most prominently voluntary carbon markets and biodiversity compliance market-like mechanisms, such as biodiversity-offsetting systems targeting the achievement of 'no net loss' of biodiversity for a given regulated sector. However, attracting private finance into restoration comes with risks, as private finance objectives in restoration often are misaligned with wider social and ecological objectives. Private finance mechanisms to date have tended to underinvest in monitoring and impact evaluation mechanisms and to favour investments in cost-effective nature-based solutions such as plantation monocultures over naturally regenerated ecosystems. Many technological and institutional solutions have been proposed, but these cannot mitigate all risks. Therefore, scaling of ecosystem restoration through market-like mechanisms requires substantial fundamental investments in governance and civil society oversight to ensure that ecological integrity and social equity is safeguarded. Here, we outline the high-level policy landscape driving restoration finance and explore the roles and potential of both public and private investment in restoration. We explain how some common mechanisms for drawing private investment into restoration work in practice. Then, we discuss some of the shortcomings of past private finance initiatives for ecosystem restoration and highlight essential lessons for how to safeguard the ecological and social outcomes of private investments in ecosystem restoration.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Biodiversidad , Restauración y Remediación Ambiental/economía , Restauración y Remediación Ambiental/métodos
9.
Curr Biol ; 34(9): R418-R434, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714175

RESUMEN

Ecosystem restoration can increase the health and resilience of nature and humanity. As a result, the international community is championing habitat restoration as a primary solution to address the dual climate and biodiversity crises. Yet most ecosystem restoration efforts to date have underperformed, failed, or been burdened by high costs that prevent upscaling. To become a primary, scalable conservation strategy, restoration efficiency and success must increase dramatically. Here, we outline how integrating ten foundational ecological theories that have not previously received much attention - from hierarchical facilitation to macroecology - into ecosystem restoration planning and management can markedly enhance restoration success. We propose a simple, systematic approach to determining which theories best align with restoration goals and are most likely to bolster their success. Armed with a century of advances in ecological theory, restoration practitioners will be better positioned to more cost-efficiently and effectively rebuild the world's ecosystems and support the resilience of our natural resources.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Ecología/métodos , Restauración y Remediación Ambiental/métodos , Biodiversidad , Cambio Climático
10.
Curr Biol ; 34(9): R399-R406, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714172

RESUMEN

Coral reefs provide food and livelihoods for hundreds of millions of coastal people in over 100 countries. Recent global estimates for the total value of goods and services that they can generate indicate around US$ 105,000-350,000 per hectare per year, but local estimates of current total economic value can be one to two orders of magnitude lower. Unfortunately, coral reefs are under threat both from local human stressors (for example, sediment and nutrient run-off from agriculture, sewage discharges, dredging, destructive fishing, land 'reclamation', overfishing) and, increasingly, from stressors related to global climate change (not only El Niño Southern Oscillation-related marine heatwaves, which cause mass bleaching and mortality of corals, but also more frequent and powerful tropical cyclones and ocean acidification). Four successive mass-bleaching events on Australia's iconic Great Barrier Reef between 2016 and 2022 (plus another one currently underway) have focused world attention on the need for urgent action to protect coral reefs. It is clear that coral reef ecosystems will continue to decline unless anthropogenic greenhouse gas emissions are reduced and innovative management strategies are developed to assist adaptation.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Arrecifes de Coral , Conservación de los Recursos Naturales/métodos , Animales , Antozoos/fisiología , Australia , Humanos , Restauración y Remediación Ambiental/métodos
11.
Curr Biol ; 34(9): R452-R472, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714177

RESUMEN

Forest restoration is being scaled up globally, carrying major expectations of environmental and societal benefits. Current discussions on ensuring the effectiveness of forest restoration are predominantly focused on the land under restoration per se. But this focus neglects the critical issue that land use and its drivers at larger spatial scales have strong implications for forest restoration outcomes, through the influence of landscape context and, importantly, potential off-site impacts of forest restoration that must be accounted for in measuring its effectiveness. To ensure intended restoration outcomes, it is crucial to integrate forest restoration into land-use planning at spatial scales large enough to account for - and address - these larger-scale influences, including the protection of existing native ecosystems. In this review, we highlight this thus-far neglected issue in conceptualizing forest restoration for the delivery of multiple desirable benefits regarding biodiversity and ecosystem services. We first make the case for the need to integrate forest restoration into large-scale land-use planning, by reviewing current evidence on the landscape-level influences and off-site impacts pertaining to forest restoration. We then discuss how science can guide the integration of forest restoration into large-scale land-use planning, by laying out key features of methodological frameworks required, reviewing the extent to which existing frameworks carry these features, and identifying methodological innovations needed to bridge the potential shortfall. Finally, we critically review the status of existing methods and data to identify future research efforts needed to advance these methodological innovations and, more broadly, the effective integration of forest restoration design into large-scale land-use planning.


Asunto(s)
Conservación de los Recursos Naturales , Bosques , Conservación de los Recursos Naturales/métodos , Agricultura Forestal/métodos , Biodiversidad , Ecosistema , Restauración y Remediación Ambiental/métodos
12.
Sci Prog ; 107(2): 368504241253720, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715402

RESUMEN

Ecosystems, biodiversity, and the human population all depend on a quality or uncontaminated environment. Quality environment provides people and wildlife access to nutrition, medications, dietary supplements, and other ecosystem services. The conservation of biodiversity-that is, species richness, abundance, heredities, and diversity-as well as the control of climate change are facilitated by such an uncontaminated environment. However, these advantages are jeopardized by newly emerging environmental chemical contaminants (EECCs) brought on by increased industrialization and urbanization. In developing countries, inadequate or poor environmental policies, infrastructure, and national standards concerning the usage, recycling, remediation, control, and management of EECCs hasten their effects. EECCs in these countries negatively affect biodiversity, ecological services and functions, and human health. This review reveals that the most deprived or vulnerable local communities in developing countries are those residing near mining or industrial areas and cultivating their crops and vegetables on contaminated soils, as is wildlife that forages or drinks in EECC-contaminated water bodies. Yet, people in these countries have limited knowledge about EECCs, their threats to human well-being, ecosystem safety, and the environment, as well as remediation technologies. Besides, efforts to efficiently control, combat, regulate, and monitor EECCs are limited. Thus, the review aims to increase public knowledge concerning EECCs in developing countries and present a comprehensive overview of the current status of EECCs. It also explores the sources and advancements in remediation techniques and the threats of EECCs to humans, ecosystems, and biodiversity.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Contaminantes Ambientales , Humanos , Conservación de los Recursos Naturales/métodos , Contaminantes Ambientales/análisis , Restauración y Remediación Ambiental/métodos , Animales , Contaminación Ambiental/prevención & control , Ecosistema
13.
Sci Rep ; 14(1): 11369, 2024 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762699

RESUMEN

Demand for ecological restoration of Earth's degraded ecosystems has increased significantly since the adoption of The Kunming-Montreal Global Biodiversity Framework in December 2022, with target 2 aiming to ensure that at least 30% of degraded ecosystems are under effective restoration by 2030. More recently, in December 2023, the Australian Parliament introduced the Nature Repair Act, which establishes a framework for the world's first legislated, national, voluntary biodiversity market. How can the effectiveness of these ambitious targets be measured? Natural Capital Accounting (NCA) provides a framework to measure changes in ecosystem condition that is applicable across ecosystems and potentially catalogue effects of restoration interventions to drive investment, improvement to practice, and ultimately, to better protect the Earth's ecosystems. However, the framework has not been tested in this context. In this progressive approach, we populated the leading global NCA framework with ecological data to quantify changes in ecosystem condition after restoration. In principle, NCA is fit for purpose, however, methodological refinements and ecological expertise are needed to unlock its full potential. These tweaks will facilitate adoption and standardisation of reporting as efforts ramp up to meet ambitious global restoration targets.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Restauración y Remediación Ambiental/métodos , Australia , Ecología
14.
Sci Total Environ ; 931: 172899, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38692328

RESUMEN

Emerging contaminants (ECs) are widely sourced persistent pollutants that pose a significant threat to the environment and human health. Their footprint spans global ecosystems, making their remediation highly challenging. In recent years, a significant amount of literature has focused on the use of biochar for remediation of heavy metals and organic pollutants in soil and water environments. However, the use of biochar for the remediation of ECs in agricultural soils has not received as much attention, and as a result, there are limited reviews available on this topic. Thus, this review aims to provide an overview of the primary types, sources, and hazards of ECs in farmland, as well as the structure, functions, and preparation types of biochar. Furthermore, this paper emphasizes the importance and prospects of three remediation strategies for ECs in cropland: (i) employing activated, modified, and composite biochar for remediation, which exhibit superior pollutant removal compared to pure biochar; (ii) exploring the potential synergistic efficiency between biochar and compost, enhancing their effectiveness in soil improvement and pollution remediation; (iii) utilizing biochar as a shelter and nutrient source for microorganisms in biochar-mediated microbial remediation, positively impacting soil properties and microbial community structure. Given the increasing global prevalence of ECs, the remediation strategies provided in this paper aim to serve as a valuable reference for future remediation of ECs-contaminated agricultural lands.


Asunto(s)
Agricultura , Carbón Orgánico , Restauración y Remediación Ambiental , Contaminantes del Suelo , Suelo , Carbón Orgánico/química , Contaminantes del Suelo/análisis , Agricultura/métodos , Restauración y Remediación Ambiental/métodos , Suelo/química , Metales Pesados/análisis
15.
Chemosphere ; 358: 142186, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38701860

RESUMEN

Fluorinated compounds (FCs) such as sulfur hexafluoride (SF6) and nitrogen trifluoride (NF3) have garnered attention due to their environmental impact. This study investigates the mineralization and removal of two potent FCs: SF6 and NF3. The results confirm that utilizing various oxalate salts leads to the formation of corresponding metallic fluorides: lithium fluoride (LiF), sodium fluoride (NaF), and potassium fluoride (KF), validating the occurrence of mineralization reactions. Among the oxalate salts, sodium oxalate demonstrates the highest mineralization efficiency in both SF6 and NF3 removal. Real-time Fourier transform infrared spectroscopy (FT-IR) gas-phase analysis confirms rapid and complete gas removal within a short reaction time using the selected oxalate salts. Meticulous mass balance calculations revealed that oxalates (LiF, NaF, and KF) yielded sulfur (S) at rates of 92.09%, 91.85%, and 84.98% following SF6 mineralization. Additionally, the conversion rates of oxalates to the corresponding metallic fluorides (LiF, NaF, and KF) after SF6 mineralization were 98.18%, 95.82%, and 95.21%, respectively. Similarly, after NF3 mineralization, these conversion rates stood at 92.18%, 90.67%, and 90.02%, respectively. The removal efficiencies for SF6 (1000 ppm) were 4.98, 12.01, and 7.23 L/g, while those for NF3 (1000 ppm) were 14.1, 12.6, and 11.7 L/g, respectively. Notably, sodium oxalate exhibits superior effectiveness, achieving 100% SF6 conversion within 30 min and 100% NF3 conversion within 50 min. This work underscores the potential of oxalate mineralization as a promising strategy for efficient and rapid removal of potent fluorinated compounds, paving the way for environmentally benign FC remediation techniques with broader implications for sustainable gas treatment technologies.


Asunto(s)
Fluoruros , Gases de Efecto Invernadero , Oxalatos , Hexafluoruro de Azufre , Oxalatos/química , Hexafluoruro de Azufre/química , Fluoruros/química , Gases de Efecto Invernadero/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Restauración y Remediación Ambiental/métodos
16.
Sci Total Environ ; 931: 172846, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38703858

RESUMEN

The development of low-cost, highly efficient adsorbent materials is of significant importance for environmental remediation. In this study, a novel material, sulfurized nano zero-valent iron loaded biomass carbon (S-nZVI/BC), was successfully synthesized by a simple manufacturing process. The preparation of S-nZVI/BC does not require the use of expensive and hazardous chemicals. Instead, residual sludge, a solid waste product, is used as feedstock. The sludge is rich in Sulfate-Reducing Bacteria (SRB), which can provide carbon and sulfur sources for the synthesis of S-nZVI/BC. It was observed that S-nZVI particles formed in situ were dispersed within BC and covered by it. Additionally, S-nZVI/BC inherited the large specific surface area and porosity of BC. The adsorption capacity of S-nZVI/BC can reach 857.55 mg g-1 Hg (II) during the remediation of mercury-polluted water. This research offers new perspectives for developing composites in terms of the low cost and harmlessness of raw materials.


Asunto(s)
Biomasa , Hierro , Mercurio , Contaminantes Químicos del Agua , Hierro/química , Contaminantes Químicos del Agua/análisis , Adsorción , Azufre/química , Restauración y Remediación Ambiental/métodos , Bacterias Reductoras del Azufre/metabolismo , Sulfatos/química
17.
Sci Total Environ ; 931: 172958, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38714255

RESUMEN

Mining activities put the Brazilian savannas, a global biodiversity hotspot, in danger of species and soil carbon losses. Experiments employing biosolids have been applied to rejuvenate this degraded ecosystem, but a lingering question yet to be answered is whether the microbiota that inhabits these impoverished soils can be recovered towards its initial steady state after vegetation recovery. Here, we selected an 18-year-old restoration chronosequence of biosolids-treated, untreated mining and native soils to investigate the soil microbiota recovery based on composition, phylogeny, and diversity, as well as the potential factors responsible for ecosystem recovery. Our results revealed that the soil microbiota holds a considerable recovery potential in the degraded Cerrado biome. Biosolids application not only improved soil health, but also led to 41.7 % recovery of the whole microbial community, featuring significantly higher microbiota diversity and enriched groups (e.g., Firmicutes) that benefit carbon storage compared to untreated mining and native soils. The recovered community showed significant compositional distinctions from the untreated mining or native soils, rather than phylogenetic differences, with physiochemical properties explaining 55 % of the overall community changes. This study advances our understanding of soil microbiota dynamics in response to disturbance and restoration by shedding light on its recovery associated with biosolid application in a degraded biodiverse ecosystem.


Asunto(s)
Microbiota , Microbiología del Suelo , Suelo , Brasil , Suelo/química , Minería , Biodiversidad , Ecosistema , Restauración y Remediación Ambiental/métodos
18.
BMC Plant Biol ; 24(1): 408, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38755583

RESUMEN

BACKGROUND: Grazing exclusion is an efficient practice to restore degraded grassland ecosystems by eliminating external disturbances and improving ecosystems' self-healing capacities, which affects the ecological processes of soil-plant systems. Grassland degradation levels play a critical role in regulating these ecological processes. However, the effects of vegetation and soil states at different degradation stages on grassland ecosystem restoration are not fully understood. To better understand this, desert steppe at three levels of degradation (light, moderate, and heavy degradation) was fenced for 6 years in Inner Mongolia, China. Community characteristics were investigated, and nutrient concentrations of the soil (0-10 cm depth) and dominant plants were measured. RESULTS: We found that grazing exclusion increased shoots' carbon (C) concentrations, C/N, and C/P, but significantly decreased shoots' nitrogen (N) and phosphorus (P) concentrations for Stipa breviflora and Cleistogenes songorica. Interestingly, there were no significant differences in nutrient concentrations of these two species among the three degraded desert steppes after grazing exclusion. After grazing exclusion, annual accumulation rates of aboveground C, N, and P pools in the heavily degraded area were the highest, but the aboveground nutrient pools were the lowest among the three degraded grasslands. Similarly, the annual recovery rates of community height, cover, and aboveground biomass in the heavily degraded desert steppe were the highest among the three degraded steppes after grazing exclusion. These results indicate that grazing exclusion is more effective for vegetation restoration in the heavily degraded desert steppe. The soil total carbon, total nitrogen, total phosphorus, available nitrogen, and available phosphorus concentrations in the moderately and heavily degraded desert steppes were significantly decreased after six years of grazing exclusion, whereas these were no changes in the lightly degraded desert steppe. Structural equation model analysis showed that the grassland degradation level mainly altered the community aboveground biomass and aboveground nutrient pool, driving the decrease in soil nutrient concentrations and accelerating nutrient transfer from soil to plant community, especially in the heavily degraded grassland. CONCLUSIONS: Our study emphasizes the importance of grassland degradation level in ecosystem restoration and provides theoretical guidance for scientific formulation of containment policies.


Asunto(s)
Pradera , Herbivoria , China , Clima Desértico , Suelo/química , Fósforo/metabolismo , Fósforo/análisis , Conservación de los Recursos Naturales , Nitrógeno/metabolismo , Poaceae , Carbono/metabolismo , Ecosistema , Nutrientes/metabolismo , Restauración y Remediación Ambiental/métodos , Animales
19.
Sci Total Environ ; 932: 172878, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38697541

RESUMEN

Excessive phosphorus (P) in eutrophic water induces cyanobacterial blooms that aggravate the burden of in-situ remediation measures. In order to ensure better ecological recovery, Flock & Lock technique has been developed to simultaneously sink cyanobacteria and immobilize P but requires a combination of flocculent and P inactivation agent. Here we synthesized a novel lanthanum-modified pyroaurite (LMP), as an alternative for Flock & Lock of cyanobacteria and phosphorus at the background of rich humic acid and suspended solids. LMP shows a P adsorption capacity of 36.0 mg/g and nearly 100 % removal of chlorophyll-a (Chl-a), turbidity, UV254 and P at a dosage (0.3 g/L) much lower than the commercial analogue (0.5 g/L). The resultant sediment (98.2 % as immobile P) exhibits sound stability without observable release of P or re-growth of cyanobacteria over a 50-day incubation period. The use of LMP also constrains the release of toxic microcystins to 1.4 µg/L from the sunk cyanobacterial cells, outperforming the commonly used polyaluminum chloride (PAC). Similar Flock & Lock efficiency could also be achieved in real eutrophic water. The outstanding Flock & Lock performance of LMP is attributable to the designed La modification. During LMP treatment, La acts as not only a P binder by formation of LaPO4, but also a coagulant to create a synergistic effect with pyroaurite. The controlled hydrolysis of surface La(III) over pyroaurite aided the possible formation of La(III)-pyroaurite networking structure, which significantly enhanced the Flock & Lock process through adsorption, charge neutralization, sweep flocculation and entrapment. In the end, the preliminary economic analysis is performed. The results demonstrate that LMP is a versatile and cost-effective agent for in-situ remediation of eutrophic waters.


Asunto(s)
Eutrofización , Lantano , Microcystis , Fósforo , Lantano/química , Contaminantes Químicos del Agua/análisis , Hidróxido de Aluminio/química , Adsorción , Restauración y Remediación Ambiental/métodos
20.
Sci Total Environ ; 932: 172927, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38719057

RESUMEN

Tire-derived rubber crumbs (RC), as a new type of microplastics (MPs), harms both the environment and human health. Excessive use of plastic, the decomposition of which generates microplastic particles, in current agricultural practices poses a significant threat to the sustainability of agricultural ecosystems, worldwide food security and human health. In this study, the application of biochar, a carbon-rich material, to soil was explored, especially in the evaluation of synthetic biochar-based community (SynCom) to alleviate RC-MP-induced stress on plant growth and soil physicochemical properties and soil microbial communities in peanuts. The results revealed that RC-MPs significantly reduced peanut shoot dry weight, root vigor, nodule quantity, plant enzyme activity, soil urease and dehydrogenase activity, as well as soil available potassium, and bacterial abundance. Moreover, the study led to the identification highly effective plant growth-promoting rhizobacteria (PGPR) from the peanut rhizosphere, which were then integrated into a SynCom and immobilized within biochar. Application of biochar-based SynCom in RC-MPs contaminated soil significantly increased peanut biomass, root vigor, nodule number, and antioxidant enzyme activity, alongside enhancing soil enzyme activity and rhizosphere bacterial abundance. Interestingly, under high-dose RC-MPs treatment, the relative abundance of rhizosphere bacteria decreased significantly, but their diversity increased significantly and exhibited distinct clustering phenomenon. In summary, the investigated biochar-based SynCom proved to be a potential soil amendment to mitigate the deleterious effects of RC-MPs on peanuts and preserve soil microbial functionality. This presents a promising solution to the challenges posed by contaminated soil, offering new avenues for remediation.


Asunto(s)
Arachis , Carbón Orgánico , Microplásticos , Microbiología del Suelo , Contaminantes del Suelo , Suelo , Carbón Orgánico/química , Arachis/microbiología , Contaminantes del Suelo/análisis , Suelo/química , Microbiota , Rizosfera , Restauración y Remediación Ambiental/métodos
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