Structure and variation of root-associated bacterial communities of Cyperus rotundus L. in the contaminated soils around Pb/Zn mine sites

Soil contamination due to mining activities is a great concern in China. Although the effects of mining pollution resulting in changes of soil characteristics and the microbiome have been documented, studies on the responses of plant root-associated microbial assemblages remain scarce. In this work, we collected bulk soil, rhizosphere soil, and root endosphere samples of Cyperus rotundus L (Cyp) plants from two Pb/Zn mines, of which, one was abandoned (SL) and the other was active (GD), to investigate the bacterial community responses across different site contamination levels and Cyp plant compartments. For comparison, one unpolluted site (SD) was included. Results revealed that soils from the SL and GD sites were seriously contaminated by metal(loid)s, including Pb, Zn, As, and Sb. Bacterial richness and diversity depended on the sampling site and plant compartment. All sample types from the SL site had the lowest bacterial diversities and their bacterial communities also exhibited distinct patterns compared to GD and SD samples. As for the specific sampling site, bacterial communities from the root endosphere exhibited different patterns from those in bulk and rhizosphere soil. Compared to the GD and SD sites, the root endosphere and the rhizosphere soil from the SL site shared core microbes, including Halomonas, Pelagibacterium, and Chelativorans, suggesting that they play key roles in Cyp plant survival in such harsh environments.

Stomatal Index of a few common tree species in the Kishangarh Marble Slurry Dump-yard area, Ajmer (Rajasthan): A case study

The size and number of the stomata present on the foliar epidermis of Tree species is directly influenced by the Suspended Particulate Matter. Marble dust is a very fine powder having approximately 40% particles below 75?m diameter of which approximately 30% are having a size less than 25?m present in the atmosphere. A comparative micro-morphological study of stomatal index of the dominant tree speciesAlbizialebbeck, Azadirachta indica, Callistemon lanceolatus growing in the vicinity of Marble slurry dump-yard, Kishangarh (Ajmer) was done from the month of April 2014 to March 2015.The stomatal index of the lower epidermis of A. indica and A. lebbeck leaves from polluted sites was found to have greater value as compared to that with those of unpolluted site during the months of May to October while in case of the rough, leathery leaves of Callistemon lanceolatus, the stomatal index value in leaves from polluted site was less during these months. This may be attributed to the prevailing winds and weather conditions in the area of study which play a crucial role in the accumulated particulate matter on the phylloplane of the selected tree species viz.A. lebbeck, A. indica,C. lanceolatus.

Heavy Metal Pollution Affects the Antioxidant Potential of Rosa canina L. Species

The content of vitamin C, carotenes, polyphenols, total carbohydrates and total soluble proteins was determined, alongside with the activity of the oxidative stress enzymes (superoxide-dismutase, catalase, peroxidase, isocitrat-dehydrogenase, ketoglutarat-dehydrogenase, succinat-dehydrogenase and malat-dehydrogenase) in Rosa canina L. samples collected from the heavy metals and arsenic polluted area around of Tarni�a closed mine, as well as from Sucevita area (as unpolluted site). The results showed an increase in the rose hip richness of nutrients and biological-active compounds, as well as the antioxidant activity of the samples from Tarnita area.We have explained our results taking into consideration the response of rosa plants to the oxidative stress produced by the accumulation of reactive oxygen species generated byexposure to pollutant factors from the contaminated area.

Seasonal biodiversity and ecological studies on the epiphytic microalgae communities in polluted and unpolluted aquatic ecosystem at Assiut, Egypt

A qualitative and quantitative study on epiphytic microalgae was carried out seasonally from November 2015 to August 2016 to follow up their community structures on aquatic macrophytes related to some physico-chemical properties of two polluted and unpolluted water bodies at Assiut, Egypt. A total of 169 species related to 64 genera of epiphytic microalgae were recorded. The most dominant algal group was Bacillariophyceae (43.2%), followed by Chlorophyceae (34.91%), Cyanophyceae (20.71%) and Euglenophyceae (1.18%). The total number of epiphytic algae fluctuated between 11.1 × 104ind.g-1plant dry wt. on Phragmites australis in summer at Nazlet Abdellah (polluted site) and 10.02 × 107ind.g-1plant dry wt. on Myriophyllum spicatum in winter at El-Wasta (unpolluted site). Some epiphytic microalgae were dominant as Pseudanabaena limnetica, Calothrix braunii, Scenedesmus acutus, and Ulnaria ulna. Others were specific on certain macrophytes as Aphanocapsa thermalis and Ulothrix sp., which grow on Phragmites australis, while Synechocystis minuscula attached itself on Myriophyllum spicatum. Analysis of PERMANOVA showed that the most important factors that induced the variation in epiphytic microalgae were the temporal variation and host plant. Water temperature, pH, nitrate, chloride, phosphate and total dissolved salts were the highest abiotic factors correlated with the variation in composition of epiphytic microalgae.

Absorption of Hazardous Pollutants by a Medicinal FernBlechnum orientaleL.

A Chinese medicinal fernBlechnum orientale(Linn) was separately collected from polluted and unpolluted sites to determine whether it could accumulate hazardous pollutants or not. Metal concentrations (Cu, Zn, Mn, Pb, Cd, Cr, As, and Hg) both in the fronds and roots and polycyclic aromatic hydrocarbons (PAHs) in the fronds of this fern were quantified. At both sites, roots ofB. orientalehad significantly higher heavy metals than the fronds. Concentrations of Pb, As, Hg, Cd, and Cu in the fronds at the polluted site were more than 2, 6, 7, 14, 5, and 13 times of those at the unpolluted site. Translocation factor and bioaccumulation factor implied thatB. orientaledid not have a good ability to transport heavy metals from the roots to the fronds. Total PAHs in the fronds at the polluted site were significantly higher than those at the unpolluted site, indicating the physiological PAHs absorption byB. orientalegrowing at polluted sites. Uptake of pollutants via stomata might be the main reason causing the significant accumulation of hazardous pollutants in the fronds ofB. orientale. Large-scale systematical survey and intensive monitoring on pollutants in this medicinal fern should be necessarily strengthened.

Hematological analysis of Micropogonias Furnieri, Desmarest, 1823, Scianidae, from two estuaries of Baixada Santista, São paulo Brazil

Hematological alterations in fish are considered a useful tool to evaluate pathological processes resulting from the exposure to environmental pollutants. The whitemouth croaker Micropogonias furnieri is a common species in estuarine areas and potentially exposed to many contaminants. In the present study, the hematological characteristics of fish collected at two sites in Baixada Santista (Santos Estuarine System - SES, a polluted site; and the Estuary of Itanhaém River - EIR, unpolluted site) del was analysed. The following blood descriptors were analyzed: number of Erythrocytes (Er), Hematocrit (Ht), Hemoglobin (Hb), Mean Corpuscular Volume (MCV) and Mean Corpuscular Hemoglobin concentration (MCHC). Fish from SES exhibited significant lower levels of Ht and increase on MCHC and Hb. Such differences are likely related to the different contamination levels found in these estuaries.

Annual dynamics of glycogen, lipids and proteins during the sexual cycle ofPerna perna(Mollusca: Bivalvia) from south-western Morocco

Field investigations onPerna pernawere carried out in 1999 in an unpolluted site (Cap Ghir) and a wastewater-polluted site (Anza) to determine the contents of glycogen, lipids and proteins in mussel samples collected every month. Sample analyses were made using the entire soft masses of male and female mussels or their gonads only. Compared to unpollutedP. perna, the glycogen and lipid concentrations found in polluted mussels showed significantly quantitative variations throughout the year; in contrast, insignificant differences were only found for protein concentrations. Female gonads contained higher rates of lipids than male ones, whereas protein contents were similar. In contrast, in entire mussels, females were richer than males, whatever the biochemical parameter considered. Apart from protein rates in December, most of highest concentrations were noted from October to November. Contrary to unpolluted mussels (of which storage components were constituted by glycogen and lipids), a different reserve strategy, mainly based on the use of lipids, followed by that of proteins would exist in theP. pernafrom the polluted bed.

Leaf breakdown patterns in a NW Italian stream: Effect of leaf type, environmental conditions and patch size

We studied the decomposition process and macroinvertebrate colonisation of leaf packs to determine to what extent leaf consumption and invertebrate abundance depend on the pollution level, season, leaf type and patch size. We exposed 400 leaf packs made of two leaf types, alder and chestnut, at two sites of the Erro River (NW Italy) with different environmental alteration levels. Leaf packs were set out as three patch sizes (alone, or in groups of 6 or 12). A first experiment was carried out in winter and a second in summer. Leaf packs were retrieved after 15, 30, 45 and 60 days of submersion to determine the leaf mass loss and to quantify the associated macroinvertebrates. Natural riverbed invertebrates were collected in the same areas. Patch size, season, leaf type and pollution level significantly affected mass loss. The breakdown process was faster for alder leaves, during summer, at the unpolluted site, and in smaller patches. Leaf type and patch size did not affect macroinvertebrate density and richness, but the highest taxon richness was found in winter and at the unpolluted site. There were more shredders and predators than in the natural riverbed. Our study supports two recent ideas regarding leaf processing in streams: that patch size influences the leaf breakdown rate and that the breakdown rate can be used to evaluate water quality and environmental health.

Shoot fluctuating asymmetry: a new and objective stress index in Norway spruce (Picea abies)

We showed that difference in length of two opposite second-order lateral shoots on first-order branches of Norway spruce (Picea abies (L.) Karst.) can be classified as fluctuating asymmetry (FA). The FA was higher (i) in trees from a heavily polluted site than in trees from an unpolluted site, (ii) in shaded trees from the understorey of a dense stand than in trees from an open site, and (iii) after needle clipping (simulated herbivory). This is the first study to demonstrate that FA of woody plants can be assessed by measuring skeletal elements (branches) rather than photosynthetic organs (leaves or needles). Our finding significantly improves the possibilities to study plant developmental stability, in particular by allowing fast and accurate assessment of the past stress levels by using information stored in branch architecture. We concluded that FA based on shoot measurements is a practicable objective stress index in Norway spruce.