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1.
BMC Plant Biol ; 24(1): 148, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418955

RESUMO

BACKGROUND: During a field survey of urban flora in Alexandria city in 2019-2022, an interesting species belonging to the Solanaceae was collected from a newly archaeological excavation site and identified as Nicotiana glutinosa L. Many visits were made to the herbaria of Egypt to confirm the species records, but no single record was found. Reviewing the available literature revealed that this tropical American taxon was never recorded in the flora of Egypt. AIMS: The present study was focused on N. glutinosa growth structure and plant macro- and micromorphology. METHODS: Ten sampling sites were covered for N. glutinosa size structure. Plant samples were examined for stem anatomy, leaf, seed, and pollen morphology. RESULTS: The species size structure reveals that the individual size index ranges from 1.33 to 150 cm, while its density ranges from 4 to 273 individuals /100 m-2. N. glutinosa has successfully established itself in one of the archaeological sites in Egypt, showing a "healthy" population with a high degree of size inequality, characterized by a relative majority of the juvenile individuals. Voucher specimens were deposited in the Herbarium of Alexandria University (ALEX) Faculty of Science, another specimen is processed to make herbarium specimens at the Herbarium of the Botanic Garden (Heneidy et al. collection, deposition number. 5502). CONCLUSIONS: From our observations, N. glutinosa seems to have invasive potential, as it shows characteristics shared by most invasive species that are thought to help in their successful establishment in new habitats. This article emphasizes the importance of monitoring and regularly reporting the threats of alien invasive species to avoid any possible negative impacts on indigenous biodiversity in the future.


Assuntos
Ecossistema , Tabaco , Humanos , Egito , Plantas , Espécies Introduzidas , Biologia
2.
Sci Rep ; 14(1): 3117, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326540

RESUMO

Sesuvium portulacastrum is a perennial halophyte of family Aizoaceae, non-native to Egypt, which was introduced from France ten years ago as an ornamental species. This study reports the detection of S. portulacastrum in the wild in Egypt. Voucher specimens were deposited in the Herbarium of Alexandria University (ALEX). A population of the species was recorded in the wild near Maruit Lake in the north-western coast of Egypt in 2018 during plant resources surveys of the region. The study aimed to assess the potential for S. portulacastrum to spread as an alien species through field observations and geospatial measurements under current conditions in its new habitat. The measured morphological parameters were higher than those recorded in its native habitats. The field observation for three years revealed that the species is proliferating and expanding in the investigated site forming large mats of mean size of up to 9 m2. The spatial extent of S. portulacastrum based on the EOO and AOO was quantified, and the expansion rate was estimated at 0.16 ha/year in the investigated site. The geospatial parameter used in the study will not only help in determining the spread rate of the alien species spatially and temporally, but also in its effective management through guiding managers in developing monitoring plans for the species under the changing climate uncertainty. Continuous monitoring and early detection of any potential threats of the introduced species are highly recommended, to avert any potential adverse impacts on native biodiversity and assess its behaviour in the wild habitat.


Assuntos
Aizoaceae , Espécies Introduzidas , Humanos , Cidadania , Egito , Plantas Tolerantes a Sal
3.
Sci Rep ; 12(1): 20370, 2022 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-36437355

RESUMO

In the present study, a green, sustainable, simple and low-cost method was adopted for the synthesis of ZnO NPs, for the first time, using the aqueous extract of sea lavender, Limonium pruinosum (L.) Chaz., as a reducing, capping, and stabilizing agent. The obtained ZnO NPs were characterized using ultraviolet-visible spectroscopy (UV-VIS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The UV-Vis spectra of the green synthesized ZnO NPs showed a strong absorption peak at about 370 nm. Both electron microscopy and XRD confirmed the hexagonal/cubic crystalline structure of ZnO NPs with an average size ~ 41 nm. It is worth noting that the cytotoxic effect of the ZnO NPs on the investigated cancer cells is dose-dependent. The IC50 of skin cancer was obtained at 409.7 µg/ml ZnO NPs. Also, the phyto-synthesized nanoparticles exhibited potent antibacterial and antifungal activity particularly against Gram negative bacteria Escherichia coli (ATCC 8739) and the pathogenic fungus Candida albicans (ATCC 10221). Furthermore, they showed considerable antioxidant potential. Thus, making them a promising biocompatible candidate for pharmacological and therapeutic applications.


Assuntos
Anti-Infecciosos , Lavandula , Nanopartículas Metálicas , Neoplasias , Plumbaginaceae , Óxido de Zinco , Óxido de Zinco/química , Antioxidantes/farmacologia , Antioxidantes/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Folhas de Planta/química , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise , Antibacterianos/química
4.
Plant Divers ; 44(5): 468-480, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36187550

RESUMO

Understanding the influence of environmental covariates on plant distribution is critical, especially for aquatic plant species. Climate change is likely to alter the distribution of aquatic species. However, knowledge of this change on the burden of aquatic macroorganisms is often fraught with difficulty. Ottelia, a model genus for studying the evolution of the aquatic family Hydrocharitaceae, is mainly distributed in slow-flowing creeks, rivers, or lakes throughout pantropical regions in the world. Due to recent rapid climate changes, natural Ottelia populations have declined significantly. By modeling the effects of climate change on the distribution of Ottelia species and assessing the degree of niche similarity, we sought to identify high suitability regions and help formulate conservation strategies. The models use known background points to determine how environmental covariates vary spatially and produce continental maps of the distribution of the Ottelia species in Africa. Additionally, we estimated the possible influences of the optimistic and extreme pessimistic representative concentration pathways scenarios RCP 4.5 and RCP 8.5 for the 2050s. Our results show that the distinct distribution patterns of studied Ottelia species were influenced by topography (elevation) and climate (e.g., mean temperature of driest quarter, annual precipitation, and precipitation of the driest month). While there is a lack of accord in defining the limiting factors for the distribution of Ottelia species, it is clear that water-temperature conditions have promising effects when kept within optimal ranges. We also note that climate change will impact Ottelia by accelerating fragmentation and habitat loss. The assessment of niche overlap revealed that Ottelia cylindrica and O . verdickii had slightly more similar niches than the other Ottelia species. The present findings identify the need to enhance conservation efforts to safeguard natural Ottelia populations and provide a theoretical basis for the distribution of various Ottelia species in Africa.

5.
Sci Rep ; 12(1): 8223, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581245

RESUMO

Drainage water in developing countries has a high abundance of pathogenic bacteria and high levels of toxic and mutagenic pollutants. Remediation of drainage water is important in water-poor counties, especially with the growing need to secure sustainability of safe water resources to fulfill increasing demands for agriculture. Here, we assess the efficiency of macrophyte Pistia stratiotes to remediate a polluted drain in Egypt, rich in macronutrients, heavy metals, and different types of pathogenic and non-pathogenic bacteria. Drainage water was sampled monthly, for a year, to assess seasonal changes in bacterial abundance, water physicochemical properties (transparency, temperature, dissolved oxygen, EC, pH, N, P, and K), and heavy metals contents (Pb, Zn, and Co) in a polluted drain dominated with P. stratiotes. The ability of P. stratiotes to rhizofiltrate the three heavy metals was calculated. The results showed seasonal variations in the plant rhizofiltration potential of Co and Salmonella abundance. The highest values of dissolved oxygen (12.36 mg/L) and macronutrient elements (N and P) were attained in the winter. The counts of total coliform, fecal coliform, fecal streptococci, and in Salmonella spp. were the highest in the summer. P. stratiotes accumulated Pb more than Zn and Co. The highest levels of rhizofiltration were in summer for Pb and Co and in the autumn for Zn. Canonical correspondence analysis (CCA) showed that the variation in the bacterial abundance and plant rhizofiltration potential was strongly and significantly affected by water-dissolved oxygen. Moreover, the rhizofiltration potential of Pb and Co showed a positive correlation with water N. Overall, P. stratiotes could be proposed as a potential biomonitor for heavy metals in polluted water.


Assuntos
Hydrocharitaceae , Metais Pesados , Poluentes Químicos da Água , Bactérias , Biodegradação Ambiental , Drenagem , Chumbo/análise , Metais Pesados/análise , Oxigênio/análise , Água/análise , Poluentes Químicos da Água/análise
6.
Biology (Basel) ; 10(6)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203088

RESUMO

The current study addressed the heavy metals accumulation potentials of seven perennial aquatic macrophytes (Cyperus alopecuroides, Echinochloa stagnina, Eichhornia crassipes, Ludwigia stolonifera, Phragmites australis, Ranunculus sceleratus and Typha domingensis) and the pollution status of three drains (Amar, El-Westany and Omar-Beck) in the Nile Delta of Egypt. Nine sites at each drain were sampled for sediment and plant analyses. Concentrations of eight metals (Fe, Cu, Zn, Mn, Co, Cd, Ni, and Pb) were determined in the sediment and the aboveground and belowground tissues of the selected macrophytes. Bioaccumulation factor (BF) and translocation factor (TF) were computed for each species. The sediment heavy metals concentrations of the three drains occurred in the following order: El-Westany > Amar > Omar-Beck. The concentrations of sediment heavy metals in the three drains were ordered as follows: Fe (438.45-615.17 mg kg-1) > Mn (341.22-481.09 mg kg-1) > Zn (245.08-383.19 mg kg-1) > Cu (205.41-289.56 mg kg-1) > Pb (31.49-97.73 mg kg-1) > Cd (13.97-55.99 mg kg-1) > Ni (14.36-39.34 mg kg-1) > Co (1.25-3.51 mg kg-1). The sediment exceeded the worldwide permissible ranges of Cu, Zn and Pb, but ranged within safe limits for Mn, Cd, Ni and Co. P. australis accumulated the highest concentrations of Fe, Co, Cd and Ni, while E. crassipes contained the highest concentrations of Cu, Zn, Mn, and Pb. Except for C. alopecuroides and Cu metal, the studied species had BF values greater than one for the investigated heavy metals. Nevertheless, the TFs of all species (except Cd in L. stolonifera) were less than one. Hence, the studied species are appropriate for accumulation, biomonitoring, and phytostabilization of the investigated metals.

7.
Biology (Basel) ; 10(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803081

RESUMO

Prosopis juliflora is one of the most problematic invasive trees in tropical and subtropical regions. Understanding driving forces affecting the potential global distribution would help in managing its current and future spread. The role of climate on the global spatial distribution of P. juliflora has been well studied, but little is known about the role of soil and human impacts as potential drivers. Here, we used maximum entropy (MaxEnt) for species distribution modelling to understand the role of climate (C), soil (S) and human impacts (H), C+S, and C+S+H in controlling the potential invasion range of P. juliflora, and to project its global potential invasive risk. We defined the top threatened global biomes, as predicted by the best-selected model. The incorporation of the edaphic factors improved the model performance and enhanced the accuracy of the outcome. Our findings revealed that the potential invasion risk increases with increases in mean temperature of the driest quarter (Bio9), soil alkalinity and clay fractions. Arid and semi-arid lands are at the highest risk of invasion than other moist biomes.

8.
Biology (Basel) ; 10(1)2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33477312

RESUMO

Climate change is an important driver of biodiversity loss and extinction of endemic montane species. In China, three endemic Juniperus spp. (Juniperus pingii var. pingii, J. tibetica, and J. komarovii) are threatened and subjected to the risk of extinction. This study aimed to predict the potential distribution of these three Juniperus species under climate change and dispersal scenarios, to identify critical drivers explaining their potential distributions, to assess the extinction risk by estimating the loss percentage in their area of occupancy (AOO), and to identify priority areas for their conservation in China. We used ensemble modeling to evaluate the impact of climate change and project AOO. Our results revealed that the projected AOOs followed a similar trend in the three Juniperus species, which predicted an entire loss of their suitable habitats under both climate and dispersal scenarios. Temperature annual range and isothermality were the most critical key variables explaining the potential distribution of these three Juniperus species; they contribute by 16-56.1% and 20.4-38.3%, respectively. Accounting for the use of different thresholds provides a balanced approach for species distribution models' applications in conservation assessment when the goal is to assess potential climatic suitability in new geographical areas. Therefore, south Sichuan and north Yunnan could be considered important priority conservation areas for in situ conservation and search for unknown populations of these three Juniperus species.

9.
Environ Sci Pollut Res Int ; 27(7): 7040-7052, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31883073

RESUMO

Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of ecosystem services (ES). There is a growing consensus regarding the merit of integrating the evaluation of ES into regional policy planning. The Yangtze River is the world's third longest and supports more than 6% of its population. However, assessing the potential impacts of different resource management policies upon ES is complicated in the Yangtze basin. To remedy this, here we designed a scenario analysis-based approach that used remotely sensed data and GIS (geographic information system) to analyze the relationships between ES (i.e., water flow regulation, water purification) and policies envisioned to improve human welfare in the Chongqing municipality, in the upper reaches of the Three Gorges Reservoir Area (TGRA) in the Yangtze basin. This watershed area has high population density and suffers from severe flood hazard and critical pollution issues. The GEOMOD modeling technique was used to predict LULC changes according to policy planning alternatives, producing scenarios by 2050 for the TGRA watershed. The GIS-based ES model (InVEST model) was developed as a tool to inform the decision-making process with the intention of aligning conservation measures with economic development. We examine policy effectiveness by comparing three scenarios for 2050: scenario-1 maintains the current policy, with no considerations of ES; scenario-2 integrates ES into policy planning; and scenario-3 integrates ES into policy planning considering the needs of local people. Our scenario-based LULC change analysis showed that the land with large increases in water flow regulation (i.e., values ≤-3000 × 103 m3 km-2) were scattered over the entire study area, while phosphorus reduction (i.e., values ≤ -30 kg km-2) were located mainly along rivers in all scenarios. Scenario-2 and scenario-3 are based on policies aiming at enhancing ES provisioning; for these, the projected ecological risks of water pollution are significantly reduced (39.97% and 37.58%, respectively). Total net changes of the investigated ES under scenario-2 or scenario-3 were almost double that occurring under scenario-1. Although scenario-2 and scenario-3 showed a near-equal total net change, water purification under scenario-2 was the greatest relative to forest expansion. However, scenario-3 offered the best future environmental development scenario, as it accounted for the demand and supply characteristics of water yield and purification in different regions. The water purification service made the greatest contribution to positive and negative effects (26%-47% and -7%, respectively) on ES provisioning. Linking water purification service to policy planning would effectively improve the overall ES. These scenario forecasting results will help the Three Gorges Dam to gain more ecological benefits via improvements to water flow regulation and the effective alleviation of degraded water quality in heavily populated regions in the Yangtze basin.


Assuntos
Ecossistema , Rios , China , Humanos , Rios/química , Água , Poluição da Água/análise
10.
Ecol Evol ; 9(24): 14295-14316, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31938520

RESUMO

Understanding the factors driving the Quaternary distribution of Abies in the Tibetan Plateau (TP) is crucial for biodiversity conservation and for predicting future anthropogenic impacts on ecosystems. Here, we collected Quaternary paleo-, palynological, and phylogeographical records from across the TP and applied ecological niche models (ENMs) to obtain a profound understanding of the different adaptation strategies and distributional changes in Abies trees in this unique area. We identified environmental variables affecting the different historical biogeographies of four related endemic Abies taxa and rebuilt their distribution patterns over different time periods, starting from the late Pleistocene. In addition, modeling and phylogeographic results were used to predict suitable refugia for Abies forrestii, A. forrestii var. georgei, A. fargesii var. faxoniana, and A. recurvata. We supplemented the ENMs by investigating pollen records and diversity patterns of cpDNA for them. The overall reconstructed distributions of these Abies taxa were dramatically different when the late Pleistocene was compared with the present. All Abies taxa gradually receded from the south toward the north in the last glacial maximum (LGM). The outcomes showed two well-differentiated distributions: A. fargesii var. faxoniana and A. recurvata occurred throughout the Longmen refuge, a temporary refuge for the LGM, while the other two Abies taxa were distributed throughout the Heqing refuge. Both the seasonality of precipitation and the mean temperature of the driest quarter played decisive roles in driving the distribution of A. fargesii var. faxoniana and A. recurvata, respectively; the annual temperature range was also a key variable that explained the distribution patterns of the other two Abies taxa. Different adaptation strategies of trees may thus explain the differing patterns of distribution over time at the TP revealed here for endemic Abies taxa.

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