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Lena Q - One of the best experts on this subject based on the ideXlab platform.
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comparison of arsenic accumulation in 18 fern species and four pteris vittata accessions
Bioresource Technology, 2010Co-Authors: Mrittunjai Srivastava, Jorge Antonio Gonzaga Santos, Pratibha Srivastava, Lena QAbstract:Abstract This study evaluated the ability and mechanisms of 19 Pteris and non- Pteris species to accumulate arsenic (As) in a hydroponic system spiked with 300 μM As. The study included four Pteris vittata accessions (China, India, Poland, and the United Kingdom), P . biaurita and 17 non- Pteris species. Among the accessions, P . vittata from China and UK were the most and the least efficient in terms of As accumulation. The non- Pteris species Chielanthes sinuta , Adiantum raddianum , Polystichum acrostichoides , Actiniopteris radiata , Pellaea rotundifolia , and Nephrolepis cordifolia concentrated As as effectively as the least efficient P. vittata ascension. As (III) in the Fronds of P . vittata accessions ranged from 59% to 89% and for non- Pteris species it ranged from 47% to 65%. Maximum As accumulation coincided with highest percentage of As (III) in the Fronds. The phosphorus (P) uptake of P. vittata accessions was 12–15 and 6–12 times greater than the As-uptake in the roots and Fronds, respectively. In contrast, the P-uptake of non- Pteris species ranged from 9 to 151 and from 4 to 162 times the As-uptake, in the roots and Fronds, respectively. Arsenic accumulation occurs at the expense of root and Frond P-uptake. Root P-reduction is lower than Frond and the P:As in the plant acquisition part (roots) is 1–3 times greater than that in accumulation part (Fronds). A . radiata , C . sinuta , and P. acrostichoides were identified as potential As accumulators.
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phytoremediation of an arsenic contaminated site using pteris vittata l a two year study
International Journal of Phytoremediation, 2006Co-Authors: G M Kertulistartar, Lena Q, C Tu, T ChirenjeAbstract:A field study was conducted to determine the efficiency of Chinese brake fern (Pteris vittata L.), an arsenic hyperaccumulator, on removal of arsenic from soil at an arsenic- contaminated site. Chinese brake ferns were planted on a site previously used to treat wood with chromated copper arsenate (CCA). Arsenic concentrations in surface and profile soil samples were determined for 2000, 2001, and 2002. In both 2001 and 2002, senesced and senescing Fronds only, as well as all Fronds, were harvested. Frond arsenic concentrations were not significantly different between the three harvests. Compared to senesced Fronds, live Fronds resulted in the greatest amount of arsenic removal. There were no significant differences in soil arsenic concentrations between 2000, 2001, and 2002, primarily due to the extreme variability in soil arsenic concentrations. However, the mean surface soil arsenic was reduced from 190 to 140 mg kg−1. Approximately 19.3 g of arsenic were removed from the soil by Chinese brake fern. The...
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effects of arsenic on concentration and distribution of nutrients in the Fronds of the arsenic hyperaccumulator pteris vittata l
Environmental Pollution, 2005Co-Authors: C Tu, Lena QAbstract:Abstract Pteris vittata was the first terrestrial plant known to hyperaccumulate arsenic (As). However, it is unclear how As hyperaccumulation influences nutrient uptake by this plant. P. vittata fern was grown in soil spiked with 0–500 mg As kg −1 in the greenhouse for 24 weeks. The concentrations of essential macro- (P, K, Ca, and Mg) and micro- (Fe, Mn, Cu, Zn, B and Mo) elements in the Fronds of different age were examined. Both macro- and micronutrients in the Fronds were found to be within the normal concentration ranges for non-hyperaccumulators. However, As hyperaccumulation did influence the elemental distribution among Fronds of different age of P. vittata . Arsenic-induced P and K enhancements in the Fronds contributed to the As-induced growth stimulation at low As levels. The Frond P/As molar ratios of 1.0 can be used as the threshold value for normal growth of P. vittata . Potassium may function as a counter-cation for As in the Fronds as shown by the As-induced K increases in the Fronds. The present findings not only demonstrate that P. vittata has the ability to maintain adequate concentrations of essential nutrients while hyperaccumulating As from the soil, but also have implications for soil management (fertilization in particular) of P. vittata in As phytoextraction practice.
Mei-cen Meng - One of the best experts on this subject based on the ideXlab platform.
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Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance
BMC, 2017Co-Authors: Le Liu, Mei-cen Meng, Deming Wang, Jinzhuang XueAbstract:Abstract Background The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the Frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. Results New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and Fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear Fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. Conclusions Cosmosperma further demonstrates diversification of Frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and Frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures
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Pollen Organ Telangiopsis sp. of Late Devonian Seed Plant and Associated Vegetative Frond.
PLOS ONE, 2016Co-Authors: Deming Wang, Mei-cen MengAbstract:Pollen organ Telangiopsis sp., associated with but not attached to vegetative Fronds, has been collected from the Upper Devonian (Famennian) Wutong Formation, Dongzhi County, Anhui Province, China. Fertile axes with terminal pollen organs are dichotomous for 2–4 times and may be proximally attached by fragmentary pinnules. Pollen organs are synangiate and borne on the top of a short stalk. Synangia are radial in symmetry and each consists of 4–8 elongate microsporangia fused at base. Microsporangia have a longitudinal dehiscence line and show a tapered apex. The associated stem is spiny and bears a vegetative Frond which bifurcates once at the basalmost part. Frond rachises possess one order of pinna arranged alternately. Pinnules are borne alternately, planate, highly dissected, and equally dichotomous for 2–3 times. Comparisons among Late Devonian seed plants recognize several branching patterns in the fertile Fronds/axes bearing terminal pollen organs. Telangiopsis sp. reinforces that the Late Devonian pollen organs are synangiate usually with basally fused microsporangia. It is suggested that the evolutionary divergence of radial and bilateral symmetries of pollen organs may have occurred in the Famennian, when the earliest seed plants evolved planate and sometimes laminate pinnules.
Xue Jinzhuang - One of the best experts on this subject based on the ideXlab platform.
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Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance
BMC EVOLUTIONARY BIOLOGY, 2017Co-Authors: Le Liu, Wang Deming, Meng Meicen, Xue JinzhuangAbstract:Background: The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the Frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. Results: New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and Fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear Fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. Conclusions: Cosmosperma further demonstrates diversification of Frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and Frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures.China Postdoctoral Science Foundation [2016 M600146]; National Natural Science Foundation of China [41672007]SCI(E)ARTICLE1
Michel Mench - One of the best experts on this subject based on the ideXlab platform.
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degradation pathways of holocellulose lignin and α cellulose from pteris vittata Fronds in sub and super critical conditions
Biomass & Bioenergy, 2012Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Michel MenchAbstract:Abstract Fern (Pteris vittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The Frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and super critical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no ‘synthetic’ materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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conversion of fern pteris vittata l biomass from a phytoremediation trial in sub and supercritical water conditions
Biomass & Bioenergy, 2011Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Frederic Marias, Michel MenchAbstract:Abstract Uncontaminated and As-contaminated Fronds of Pteris vittata L., an As-hyperaccumulator fern used to phytoextract As from contaminated soils and water, were converted by sub-critical water (300 °C, 25 Pa) and supercritical water (400 °C, 25 Pa) treatments. Frond biomass was reduced between 70 and 77%. Compared to sub-critical conditions, supercritical conditions decreased C and inorganic contents in both the solid and liquid phases for uncontaminated and contaminated Fronds and promoted CH 4 formation. Higher As, Fe and Zn contents in contaminated Fronds promoted decreasing C contents and the formations of cyclopentenones and benzenediols in the liquid phase. Al, Fe, P, Zn and Ca mainly remained in the solid phase whereas As and S were transferred to the liquid phase for both phytomasses. As the temperature increased from 300 °C to 400 °C, the concentrations of cyclopentenones and phenols in the liquid phase rose while those of guaiacols and other compounds decreased for both phytomasses. Arsenic in the liquid phase was removed by sorption on hydrous iron oxide.
Maria Thessaloulegaki - One of the best experts on this subject based on the ideXlab platform.
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vulnerability of marine habitats to the invasive green alga caulerpa racemosa var cylindracea within a marine protected area
Marine Environmental Research, 2010Co-Authors: Stelios Katsanevakis, Yiannis Issaris, Dimitris Poursanidis, Maria ThessaloulegakiAbstract:Abstract The relative vulnerability of various habitat types to Caulerpa racemosa var. cylindracea invasion was investigated in the National Marine Park of Zakynthos (Ionian Sea, Greece). The density of C. racemosa Fronds was modelled with generalized additive models for location, scale and shape (GAMLSS), based on an information theory approach. The species was present in as much as 33% of 748 randomly placed quadrats, which documents its aggressive establishment in the area. The probability of presence of the alga within randomly placed 20 × 20 cm quadrats was 83% on ‘matte morte’ (zones of fibrous remnants of a former Posidonia oceanica bed), 69% on rocky bottoms, 86% along the margins of P. oceanica meadows, 10% on sandy/muddy substrates, and 6% within P. oceanica meadows. The high Frond density on ‘matte morte’ and rocky bottoms indicates their high vulnerability. The lowest Frond density was observed within P. oceanica meadows. However, on the margins of P. oceanica meadows and within gaps in fragmented meadows relative high C. racemosa densities were observed. Such gaps within meadows represent spots of high vulnerability to C. racemosa invasion.
