Springer Science and Business Media LLC

Việc sử dụng ngày càng nhiều công nghệ nano có nghĩa là các vật liệu nano sẽ xâm nhập vào môi trường. Do đó, dữ liệu sinh thái độc học là cần thiết để có thể thực hiện các đánh giá rủi ro đầy đủ. Trong nghiên cứu này, chúng tôi đã sử dụng một thử nghiệm sinh sản giun đất tiêu chuẩn với Eisenia andrei để đánh giá ba loại hạt nano TiO₂ (NM-101, NM-102, NM-103). Thử nghiệm được thực hiện trong đất cát tự nhiên (RefeSol 01A) theo Hướng dẫn Thử nghiệm số 222 của Tổ chức Hợp tác và Phát triển Kinh tế. Các hạt nano khác nhau về một số khía cạnh, chẳng hạn như cấu trúc tinh thể, kích thước và sự hiện diện hoặc không có lớp phủ.

Các hạt nano chưa được phủ kích thích việc sinh sản của giun đất theo kiểu phụ thuộc vào nồng độ trong thử nghiệm mùa đông, làm tăng số lượng con cái lên đến 50% so với nhóm đối chứng. Tuy nhiên, không có sự kích thích khi thử nghiệm tương tự được thực hiện vào mùa hè. Điều này phản ánh một nhịp điệu chu kỳ năm ở đất đối chứng, được đặc trưng bởi sự sản xuất số lượng trưởng thành lớn hơn nhiều vào mùa hè so với mùa đông. Tác động của các hạt nano TiO₂ chưa được phủ là làm giảm hoặc loại bỏ sự khác biệt theo chu kỳ năm bằng cách tăng tỷ lệ sinh sản vào mùa đông. Các hạt nano TiO₂ có lớp phủ không ảnh hưởng đến sự sinh sản của giun đất.

TiO₂ có vẻ tác động đến hoạt động sinh sản của giun đất bằng cách xóa bỏ nhịp điệu năm ảnh hưởng tiêu cực đến việc sinh sản vào mùa đông. Cần có thêm các thí nghiệm để xác định (1) cơ chế tác động của các hạt nano, (2) các tham số quan trọng gây ra tác động (ví dụ: các tham số đất liên quan), và (3) ý nghĩa môi trường của việc sinh sản liên tục của giun đất mà chúng tôi đã quan sát trong điều kiện phòng thí nghiệm.

The prevalence of antibiotic resistance genes (ARGs) in animal manure poses a threat to environmental safety. Organic fertilizers fermented by livestock and poultry manure are directly applied to farmland and have the potential to cause outbreaks of bacterial resistance in agricultural environments. This study investigated the composition of ARGs in different animal manures and their derived organic fertilizers. The results showed that the abundance of several ARGs, such as sul2, TetB-01, TetG-01 and TetM-01, in organic fertilizer samples was 12–96% lower than that in animal manure. However, the abundance of TetK and ermC was higher in animal manure than in organic fertilizers. No correlation between ARGs and environmental factors such as pH, TN, and antibiotics was observed by redundancy analysis (RDA). Procrustes analysis revealed a significant correlation between bacterial community structures and ARG abundance (r = 0.799, p < 0.01). Nonmetric multidimensional scaling (NMDS) analysis suggested that microorganisms in organic fertilizer may be derived from animal manure. Additionally, the abundance of pathogenic bacteria (especially Actinomadura) would increase rather than decrease in manure compared to organic fertilizer. The diversity and abundance of most ARGs significantly decreased from animal manure to organic fertilizer. Microorganisms in the prepared organic fertilizer may mainly be inherited from the animal manure. The results also showed that the pathogens in the prepared organic fertilizer would significantly reduce, but would still cause partial pathogen proliferation.

The coexistence of agricultural production with and without the use of genetically modified (GV) crops is supposed to be made possible in Germany by regulations, which include minimal distances of GV-fields to potentially susceptible crop fields and habitats. To explore the impact of these regulations on region specific coexistence potentials, we broadened the applicability of an existing method for the simulation of the spatial distribution of arable fields cropped with conventional, organic and GV-maize. We used simulations which combine a variety of minimum distances of GV-maize fields to assess regional specific options and limitations for coexistence. An existing method was extended to be applicable for different spatial scales, from the large (e.g. Federal State) to small (e.g. municipality). Input data consisted of cropping statistics, geometry of arable fields and protected areas. Scenarios of cropping situations included various minimal distances between GV-maize fields and protected areas and various proportions of maize within the areas. The results of the simulations represent possible distribution patterns of non-GV and GV-maize fields as well as the size of the remaining area in which additional GV-maize can be grown without violating the minimal distance rules. As suspected, increasing proportions of GV-maize and increasing minimal distances lower the areas suitable for additional GV-maize. However, the relation between the area of GV-maize grown and those suitable for GV-maize cultivation varied between the scenarios. Moreover, the variability between the municipalities was even more evident, due to varying landscape structure (proportion of maize, the ratio total arable land to maize, proportion of protected areas). Areas with high proportions of GV-maize, of protected areas and of maize could be problematical for coexistence. We discuss these parameters with regard to other coexistence studies. Our method is suitable to simulate the spatial distribution of fields cultivated with GV-crops and non-GV-crops on various scales. Simulations on the scale of a Federal State reveals those areas, in which coexistence could be problematical. Simulations on a county scale, however, allow more insight into options and restrictions for coexistence in relation to landscape structural characteristics, which also can be transferred to larger scales. On the scale of municipalities simulations can help to analyse the limits of coexistence in areas of high conflict potential, moreover this level is more realistic with regard to practical agricultural decisions on the farm level. Die Koexistenz verschiedener landwirtschaftlicher Produktionsformen – mit und ohne Anbau von gentechnisch veränderten Pflanzen (GVO) – soll durch gesetzlich fixierte Regeln ermöglicht werden, die unter anderem die Mindestabstände von GVO-Anbauflächen zu potenziell empfindlichen anderen Ackerflächen und Biotopen festlegen. Hier wurde eine Methode weiterentwickelt zur Simulation der räumlichen Verteilung der Anbauflächen von konventionellem, ökologischem und GV-Mais um regionsspezifische Koexistenzpotenziale von gentechnisch verändertem Mais, sowie potenzielle Konfliktgebiete zu identifizieren. Eine für Brandenburg entwickelte GIS-Simulationsmethode wurde durch die Verwendung flächendeckend vorhandener Daten so erweitert, dass sie bundesweit übertragbar ist und auf unterschiedlichen räumlichen Skalenebenen angewandt werden kann, von großräumig (Bundesland) bis lokal (Gemeinde). Als Eingangsdaten wurden Anbaustatistiken sowie Geometrien der Ackerflächen und von FFH- und Naturschutzgebieten verwendet. In den Szenarien wurden Abstandsregelungen zwischen Maisanbauflächen und zu Schutzgebieten und der GV-Maisanteil variiert. Die Ergebnisse der Simulation sind mögliche räumliche Verteilungen von Nicht-GV-Mais und GV-Mais sowie die potenziell für den Anbau von GV-Mais zur Verfügung stehende Fläche. Mit zunehmendem GV-Maisanteil und Mindestabständen zu Schutzgebieten wird die für den GV-Mais zur Verfügung stehende Fläche stärker ausgeschöpft. Der Anteil des GV-Mais an der potenziell für den Anbau von GV-Mais zur Verfügung stehenden Fläche variierte zwischen den Szenarien, und noch stärker jedoch regional zwischen den Landkreisen, verursacht durch deren verschiedene agrar- und landschaftsstrukturelle Ausstattung (Maisanbauanteil, Verhältnis Ackerlandsanteil/Maisanbauanteil, Schutzgebietsanteil). Ein räumliches Konfliktpotenzial bei der Umsetzung der Koexistenz ist in Gebieten hohen Nutzungsdrucks zu erwarten, d.h. in denen sowohl der Maisanbauanteil an der Ackerfläche und der Anbauanteil von GV-Mais, als auch der Schutzgebietsanteil hoch sind. Diese Faktoren werden diskutiert in Bezug zu Ergebnissen weiterer Koexistenzstudien. Die vorgestellte Methode ist geeignet, die räumliche Verteilung des Anbaus von Nicht-GV-Mais und GV-Mais auf unterschiedlichen Skalenebenen zu simulieren: Die Ebene eines Bundeslandes liefert Hinweise auf Gebiete, in denen die Koexistenz problematisch sein könnte und kann als Grundlage weiterer Berechnungen, wie zum Beispiel der Modellierung von Genflüssen auf Landesebene dienen. Die Simulation auf der Ebene eines Landkreises oder einer Gemeinde ermöglicht genauere Aussagen über die Möglichkeiten und Grenzen der Koexistenz. Auf der Ebene der Landkreise können z.B. unterschiedliche agrar- und landschaftsstrukturelle Situationen untersucht und für eine nachfolgende Regionalisierung angewandt werden. Die Ebene der Gemeinden erlaubt die Analyse der Grenzen der Koexistenz für Gebiete mit höherem räumlichen Konfliktpotenzial. Simulationen auf lokaler Ebene erscheinen darüber hinaus näher an den Entscheidungsmöglichkeiten der landwirtschaftlichen Praxis.

To realize the integrated remediation of SW/GW and soil in the rural river network area, the integrated remediation in rural river network area project (IR-RRNA), funded by the Ministry of Science and Technology of the People’s Republic of China, has been launched. In eastern China, the rural river network area (RRNA) is an anthropic active area characterized by its rapid economic development and high gross national product. However, the water environmental pollution in these areas is increasingly severe, which has greatly hindered their sustainable development. Especially, the frequent interactions between surface/groundwater (SW–GW) have intensified the pollution migration and transformation in RRNA. The IR-RRNA (2019–2022) will apply the related interdisciplinary and methodological knowledge to elucidate the transportation and transformation of pollutants in water and soil during SW–GW interaction and develop remediation technologies of surface water, groundwater, and soil suitable for the RRNA. In this way, to realize the remediation technologies integration for surface/groundwater and soil in RRNA and implementing application demonstration. Meanwhile, a technical guideline will be compiled for the integrated remediation suitable for the RRNA. This project is conducive to addressing the urgent environmental problems as well as promoting rural economic revitalization and ecological environment optimization.

The European Water Framework Directive (WFD) requires the monitoring of biota—preferably fish—to check the compliance of tissue concentrations of priority substances (PS) against substance-specific environmental quality standards (EQSs). In monitoring programs, different fish species are covered, which often are secondary consumers with a trophic level (TL) of about 3. For harmonization, a normalization of monitoring data to a common trophic level is proposed, i.e., TL 4 (predatory fish) in freshwaters, so that data would be sufficiently protective. For normalization, the biomagnification properties of the chemicals can be considered by applying substance-specific trophic magnification factors (TMFs). Alternatively, TL-corrected biomagnification factors (BMFTLs) may be applied. Since it is impractical to derive site-specific TMFs or BMFTLs, often data from literature will be used for normalization. However, available literature values for TMFs and BMFTLs are quite varying. In the present study, the use of literature-derived TMFs and BMFTLs in data normalization is studied more closely. An extensive literature evaluation was conducted to identify appropriate TMFs for the WFD PS polybrominated diphenyl ethers (PBDE), hexachlorobenzene, perfluorooctane sulfonate (PFOS), dioxins and dioxin-like compounds (PCDD/F + dl-PCB), hexabromocyclododecane, and mercury. The TMFs eventually derived were applied to PS monitoring data sets of fish from different trophic levels (chub, bream, roach, and perch) from two German rivers. For comparison, PFOS and PBDE data were also normalized using literature-retrieved BMFTLs. The evaluation illustrates that published TMFs and BMFTLs for WFD PS are quite variable and the selection of appropriate values for TL 4 normalization can be challenging. The normalized concentrations partly included large uncertainties when considering the range of selected TMFs, but indicated whether an EQS exceedance at TL 4 can be expected. Normalization of the fish monitoring data revealed that levels of substances accumulating in the food web (TMF or BMF > 1) can be underestimated when relying on fish with TL < 4 for EQS compliance assessment. The evaluation also revealed that TMF specifically derived for freshwater ecosystems in Europe would be advantageous. Field-derived BMFTLs seemed to be no appropriate alternative to TMFs, because they can vary even stronger than TMFs.

Currently, nanotechnology and nanoparticles have quickly emerged and have gained the attention of scientists due to their massive applications in environmental sectors. However, these environmental applications of silver nanoparticles potentially cause serious effects on terrestrial and aquatic organisms. In the current study, freshwater fish C. carpio were exposed to blood-mediated silver nanoparticles for toxicity, mortality, bioaccumulation, and histological alterations. Silver nanoparticles were fabricated using animal blood serum and their toxic effect was studied against common carp fish at different concentrations levels (0.03, 0.06, and 0.09 mg/L). The findings have revealed a little influence of blood-induced silver nanoparticles on fish behavior at the highest concentration (0.09 mg/L). However, bioaccumulation of blood-mediated silver nanoparticles was reported in different organs of fish. Maximum bioaccumulation of silver nanoparticles was reported in the liver, followed by the intestine, gills, and muscles. Furthermore, the findings have shown that the bioaccumulation of silver nanoparticles led to histopathological alterations; including damaged structure of gill tissue and have caused necrosis. It is summarized that histopathological alteration in gill and intestine mostly occurred by the highest concentration of blood-induced silver nanoparticles (0.09 mg/L). This study provides evidence of the silver nanoparticles influence on aquatic life; however, further systematic studies are crucial to access the effects of AgNPs on aquatic life.

Growing microbial resistance towards the existing antimicrobial materials appears as the greatest challenge for the scientific community and development of new antimicrobial materials has become an important research objective. In this work, antimicrobial activity of silver-coated hollow poly(methylmethacrylate) microspheres (PMB) having a diameter of 20–80 µm was evaluated against two bacterial strains, Gram-positive Bacillus subtilis (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). The polymeric PMMA microspheres were synthesized by solvent evaporation technique and were further coated with silver (Ag) under microwave irradiation on their outer surface using an electroless plating technique. It was observed that Ag was uniformly coated on the surface of microspheres. Characterization of the coated microspheres was performed using optical microscope (OMS), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), UV–Vis spectroscopy, FTIR spectroscopy and thermogravimetric analysis (TGA) techniques. We have shown that the silver-coated microspheres were potent bactericidal material for water as they are highly active against the tested microorganisms. The results of the antibacterial tests indicated that APMB particles showed enhanced inhibition rate for both Gram-positive and Gram-negative bacteria and also exhibited dose-dependent antibacterial ability. The diameters of zone of inhibition were14.3 ± 0.2 mm against B. subtilis and 15.2 ± 0.9 mm against E. coli at a concentration of 8 mg. At this concentration, total removal of both Bacillus subtilis and Escherichia coli was observed. The results of shake flask technique for a concentration of 8 mg showed no bacterial presence after 24 h in both the cases. In other words, the material acted efficiently in bringing down the bacterial count to zero level for the tested strains. During the experiments, we have also confirmed that use of this material for water disinfection does not cause leaching of silver ion in to the water solution. The material can be successfully regenerated by backwashing with water. Considering the cost-effective synthesis, ability to regenerate and very low level of leaching of the material, it can be projected as an advanced material for water disinfection and antimicrobial application.

Insight into temporal–spatial variations of dissolved organic matter (DOM) fractions were undertaken to trace potential factors toward a further understanding aquatic environment in Lake Shahu, a brackish-water lake in northwest China, using synchronous fluorescence spectroscopy (SFS) combined with principal component analysis (PCA), second derivative and canonical correlation analysis (CCA). Five fluorescence peaks were extracted from SFS by PCA, including tyrosine-like fluorescence (TYLF), tryptophan-like fluorescence (TRLF), microbial humic-like fluorescence (MHLF), fulvic-like fluorescence (FLF), and humic-like fluorescence (HLF), whose relative contents were obtained by second derivative synchronous fluorescence spectroscopy. The increasing order of total fluorescence components contents was July (11,789.38 ± 12,752.61) < April (12,667.58 ± 15,246.91) < November (19,748.87 ± 17,192.13), which was attributed to tremendous enhancement in TYLF content from April (1615.56 ± 258.56) to November (5631.96 ± 634.82). The PLF (the sum of TYLF and TRLF) dominated the fluorescence components, whose proportion was 40.55, 37.09, or 46.91% in April, July, or November. DOM fractions in November were distinguished from April and July, which could be attributed to that water of the Yellow River was continuously loaded into the lake as water replenishment from April to September. From the replenishment period to non-replenishment, the contents of the five components gradually changed from low in the middle and high around the lake to high throughout entire lake. Based on the CCA results, the potential factors included TYLF, TRLF, MHLF, SD, and BOD5 in April, which were relative to organic matter pollution. The potential factors contained TYLF, TRLF, FLF, Chl-a, TP, CODCr, and DO in July, indicating the enrichment of TP lead algae and plants growth. The potential factors in November consisted of TYLF, TRLF, CODCr, SD, TN, and FLF, representing residue of the algae and plants have been deeply degraded. The replenishment of water led to enrichment of TP, resulting in growth of algae and plants, and was the key factor of water quality fluctuations. This work provided a workflow from perspective of DOM to reveal causes of water quality fluctuations in a brackish-water lake and may be applied to other types of waterbodies.