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Journal of Forestry Research 2013年第4期24卷 715-720页

作者： Gitamani Dutta Ashalata Devi department of environmental science Tezpur University

We investigated the plant population structure and the phy- tosociological and regeneration status in two disturbed tropical forests in Assam Province, the Hojai Reserve Forest and Kumorakata Reserve Forest. A total of 166 species （80 trees, 20 shrubs and 66 herbs） of 136 genera and 63 families were recorded in both study sites. The disturbance index at the two sites, Kumorakata Reserve Forest and Hojai Reserve Forest, were recorded at 11.4% and 3.70% respectively. Reverse J-shaped population curve and exploitation of tree species in higher girth classes were recorded at both study sites. In the girth classes （10-30 cm, 30-60 cm, 60-90 cm and 90-120 cm in size） the percentage of cut stump density was higher than the percentage of individual living trees. The 18% （Kumorakata Reserve Forest） and 7% （Hojai Reserve Forest） spe- cies were recorded as not regenerating. Illegal felling and over-exploitation of forest resources may lead to species-specific changes in the population structure and can alter the future structure and composi- tion of the forests.

关键词： plant diversity regeneration disturbance population struc-ture Assam India

Improved Performance of Membrane Bioreactor by Sludge Ozonation for Reduction of Excess Sludge Production

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Journal of Donghua University(English Edition) 2009年第2期26卷 171-176页

作者：蒋轶锋何圣兵陈建孟 College of biological and environmental Engineering Zhejiang University of Technology School of environmental science and Engineering Shanghai Jiaotong University

To seek for an alternative solution for the treatment and disposal of excess activated sludge,a hybrid system of membrane bioreactor(MBR)coupled with ozonation process(i.e.,ozonation run)was set up to treat the domestic wastewater.A reference run without ozonation was also preformed as a *** optimal ozone dose of 0.16mg O3·mg MLVSS-1 used for the sludge solubilization in the ozonation run was firstly determined through the batch sludge ozonation tests.A 40-day continuous operation of the two parallel systems demonstrated that circulation of ozonized sludge as lysate did not impact the performance of MBR in terms of organic and ammonia *** the contrary,an improvement in TN removal(by 7.7%)and sludge reduction(by 54%)was observed in the ozonation-combined MBR,and it was furthermore illustrated by the calculation of the mass balance based on the COD and TN *** addition,ozonation did not deteriorate the sludge activities for the ozonation run,indicating that not much inert organic materials built up in the *** VSS/SS ratio and lower amount of filamentous bacteria after ozonation treatment on the other hand improved the sludge settleability,as lower and constant Sluge Volume Index(SVI)values were detected in the ozonation run.

关键词： membrane bioreuctor ( MBR ) ozonation nitrogen excess sludge

Litterfall,decomposition and nutrient release of Shorea robusta and Tectona grandis in a sub-tropical forest of West Bengal,Eastern India

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Journal of Forestry Research 2016年第5期27卷 1055-1065页

作者： Chittaranjan Das Naba Kumar Mondal department of environmental science The University of Burdwan

We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant （k） of decomposed leaf litter was distinctly higher for T. grandis （2.70 ± 0.50 a-1） compared to S. robusta （2.41 ±0.30 a-1）. Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis （P 〈 0.01）. Nutrient use efficiency （NUE） and nutrient accumulation index （NAI） of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order： N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release （K 〉 P 〉 N） during decomposition of their leaf *** of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.

关键词： Decay constant Lignin Litterfall Nutrientreturn Decomposition Nutrient use efficiency

Nitrous Oxide Emissions from Fields with Different Wheat and Rice Varieties

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Pedosphere 2012年第1期22卷 112-121页

作者： B.GOGOI K.K.BARUAH department of environmental science Tezpur University

Plant species of cropping systems may affect nitrous oxide （N2O） emissions. A field experiment was conducted to investigate dynamics of N2O emissions from rice-wheat fields from December 2006 to June 2007 and the relationships of soil and plant parameters with N2O emissions. The results indicated that N2O emissions from different wheat varieties ranged front 12 to 291 Ixg N2O-N m-2 h 1 and seasonal N2O emissions ranged from 312 to 385 mg N2O-N m -2 In the rice season, it was from 11 to 154 μg N2O-N m-2 h-1 with seasonal N2O emission of 190-216 mg N2O-N m-2. The seasonal integrated flux of N2O differed significantly among wheat and rice varieties showed higher seasonal N2O emissions. In the wheat season, N2O The wheat variety HUW 234 and rice variety Joymoti emissions correlated with soil organic carbon （SOC）, soil NO3-N, soil temperature, shoot dry weight, and root dry weight. Among the variables assessed, soil temperature followed by SOC and soil NO3-N were considered as the important variables influencing N2O emission. N2O emission in the rice season was significantly correlated with SOC, soil NO3-N, soil temperature, leaf area, shoot dry weight, and root dry weight. The main driving forces influencing N2O emission in the rice season were soil NO3-N, leaf area, and SOC.

关键词： nitrous oxide flux plant characteristics rice field soil factors wheat field

Dynamic fate modeling of γ-hexachlorocyclohexane in the lower reaches of the Liao River

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Frontiers of environmental science & Engineering 2007年第2期1卷 166-171页

作者： LIU Zhenyu YANG Fenglin QUAN Xie ZHANG Xiaohong department of environmental science and Technology School of Environmental and Biological Science&TechnologyDalian University of TechnologyDalian 116024China environmental Protection Company of Dalian Dalian 116023China

A QWASI model dependent on temperature is parameterized to describe the long-term fate of persistent organic pollutants(POPs)in the Liao *** model parameters,namely fugacity capacity,degradation rate,and transfer coefficient,are profoundly affected by *** model is used to simulate the fate of γ-hexachlorocyclohexane(c-HCH)in the lower reaches of the Liao River from 1998 to *** results show that c-HCH fugacity capacities in air,water,and sediment increase as temperature decreases,and the transfer and transformation rate coefficients increase as temperature *** varia-tions of transfer and transformation parameter D values depend on fugacity capacities,and transfer and transformation coefficients *** performance of the model is evaluated by comparing the predicted and observed concentrations in the water and sediment of the Liao *** predicted values agree well with the observed value in the order of magnitude,in most cases within the factor of *** is believed that the model is appropriate for simulating the long term fate of POPs in the Liao River.

关键词： QWASI model fate,γ-HCH persistent organic pollutants(POPs) temperature

Risk assessment of dietary exposure to PCDD/Fs, DL-PCBs and NDL-PCBs of Hong Kong resident

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science China Chemistry 2015年第6期58卷 1082-1088页

作者： Weiguang Xu Zongwei Cai State Key Laboratory of environmental and biological Analysis department of Chemistry Hong Kong Baptist University

Concentrations of PCDD/Fs, dioxin-like PCBs as well as six indicator PCBs were determined in animal origin foods collected from Hong Kong retail market during 2008-2010. The dietary intake of an average Hong Kong adult resident was estimated to be 0.806-0.833 pg WHO-TEQ kg^-1 b.w. d^-1 of dioxin-like compounds, lower than the tolerable daily intake introduced by WHO. The 95th percentile consumer were exposed by dietary at the level of 2.72 to 2.81 pg WHO-TEQ kg^-1 b.w. d^-1 or 81.6-84.3 pg WHO-TEQ kg^-1 b.w. month^-1 , higher than 70 pg WHO-TEQ kg t b.w. month^-1. DL-PCBs contributed 49.2% of total TEQ intake. The daily intake of indicator PCB was 2.83 ng kg^-1 b.w. d^-1. Approximately 2/3 of dietary intake of dioxin-like compounds came from sea food products. Ten brands of infant formula products were tested and the potential dietary intake of formula-fed infants of Hong Kong was estimated to be 1.46-1.58 pg WHO-TEQ kg^-1 b.w. d^-1 during 1st month and decreases afterwards.

关键词： PCDD/Fs PCBs food dietary intake

Antisense therapy:a potential breakthrough in the treatment of neurodegenerative diseases

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Neural Regeneration Research 2024年第5期19卷 1027-1035页

作者： Roberta Romano Cecilia Bucci department of biological and environmental sciences and Technologies(DiSTeBA) University of SalentoLecceItaly

Neurodegenerative diseases are a group of disorders characterized by the progressive degeneration of neurons in the central or peripheral nervous ***,there is no cure for neurodegenerative diseases and this means a heavy burden for patients and the health system ***,it is necessary to find new therapeutic approaches,and antisense therapies offer this possibility,having the great advantage of not modifying cellular genome and potentially being *** preclinical and clinical studies aim to test the safety and effectiveness of antisense therapies in the treatment of neurodegenerative *** objective of this review is to summarize the recent advances in the development of these new technologies to treat the most common neurodegenerative diseases,with a focus on those antisense therapies that have already received the approval of the *** and Drug Administration.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis antisense oligonucleotide Huntington’s disease neurodegenerative disorders Parkinson’s disease siRNA

Microwave thermal remediation of crude oil contaminated soil enhanced by carbon fiber

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Journal of environmental sciences 2009年第9期21卷 1290-1295页

作者： LI Dawei,ZHANG Yaobin,QUAN Xie,ZHAO Yazhi Key Laboratory of Industrial Ecology and environmental Engineering,Ministry of Education of China,School of environmental and biological science and Technology,Dalian University of Technology,Dalian 116024,China [a]Key Laboratory of Industrial Ecology and environmental Engineering Ministry of Education of China School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024 China

Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber （CF） was explored. The contaminated soil was treated with 2.45 GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700℃ within 4 min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

关键词： microwave heating crude oil remediation carbon fiber

Dinophysoid dinoflagellates from subphotic depths:Amphisolenia ***,Dinofurcula tricornuta ***.,and Dinophysis profunda ***.(Dinophysales,Dinophyceae)

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Journal of Oceanology and Limnology 2022年第2期40卷 703-711页

作者： Fernando GÓMEZ department of biological and environmental sciences and Technologies University of SalentoLecce 73100Italy

Three species of dinophysoid planktonic dinoflagellates are described from the eastern Mediterranean *** *** was collected at 70-m depth in the Ionian *** small species showed a more asymmetric midbody and a proportionally longer neck when compared to the closer relative *** individuals of Dinofurcula tricornuta *** at 154-m depth in the Marmara Sea are characterized by three posterior-oriented processes when compared to its congeneric *** is the first record of the genus Dinofurcula beyond the eastern tropical Pacific *** profunda *** at 500-m depth in the Ionian Sea is characterized by ovate hypotheca and a serrate crest-like left sulcal list when compared to its close relative *** findings evidence an undescribed biodiversity in the under-sampled subphotic depths.

关键词： deep ocean Dinophyta Dinoflagellata Mediterranean Sea mesopelagic new species

Isolation and characteristics of a novel biphenyl-degrading bacterial strain,Dyella ginsengisoli LA-4

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Journal of environmental sciences 2009年第2期21卷 211-217页

作者： LI Ang,QU Yuanyuan,ZHOU Jiti,GOU Min School of environmental and biological science and Technology,Key Laboratory of Industrial Ecology and environmental Engineering(Ministry of Education,China),Dalian University of Technology,Dalian 116024,China. School of environmental and biological science and Technology Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education China) Dalian University of Technology Dalian 116024 China

A novel biphenyl-degrading bacterial strain LA-4 was isolated from activated sludge. It was identified as Dyella ginsengisoli according to phylogenetic similarity of 16S rRNA gene sequence. This isolate could utilize biphenyl as sole source of carbon and energy, which degraded over 95 mg/L biphenyl within 36 h. The major metabolites formed from biphenyl, such as 2-hydroxy-6-oxo-6- phenylhexa-2,4-dienoic acid （HOPDA） and benzoic acid, were identified by LC-MS. The crude cell extract of strain LA-4 exhibited the activity of 2,3-dihydroxybiphenyl 1,2-dioxygenase （2,3-DHBD） and the kinetic parameters Km was 26.48 μmol/L and Vmax was 8.12 U/mg protein. A conserved region of the biphenyl dioxygenase gene bphA1 of strain LA-4 was amplified by PCR and confirmed by DNA sequencing.

关键词： Dyella ginsengisoli biphenyl biodegradation metabolic pathway biphenyl dioxygenase