Ultra-high specific surface area activated carbon from Taihu cyanobacteria via KOH activation for enhanced methylene blue adsorption

Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu cyanobacteria.When the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs possessed an ultra-high specific surface(2178.90 m^(2)·g^(-1))and plenty of micro-and meso-pores,as well as a high pore volume(1.01 cm^(3)·g^(-1)).Ascribed to ultra-high surface area,π-π interaction,electrostatic interaction,as well as hydrogen-bonding interactions,the CBACs displayed huge superiority in efficient dye removal.The saturated methylene blue adsorption capacity by CBACs could be as high as 1143.4 mg·g^(-1),superior to that of other reported biomass-activated carbons.The adsorption was endothermic and modeled well by the pseudo-second-order kinetic,intra-particle diffusion,and Langmuir models.This work presented the effectiveness of Taihu cyanobacteria adsorbent ascribed to its super large specific surface area and high adsorption ability.

Living Habits of Orient Fruit Fly in Taihu Area

[ Objective] The aim was to supply technical basis for developing quarantine and control techniques for orient fruit fly. [ Method] By utilizing facilities including rearing chamber and rearing cage, the population of orient fruit fly was established and sustained by using the methods of artificial feeding and fruit culture, and the continuous indoor biological observation was carried out. The isolated enclosure equipped with temperature and humidity recorder was established in Dongshan area of Taihu for cultivating various species of host plants, then the living habits of orient fruit fly were observed everyday. [ Result] Through feeding and observation in lab, the living habit of adult, larva, pupa and eggs of orient fruit fly were studied; the impact of soil depth on the emergence rate of pupa were conducted, and the result indicated that when the soil layer depth increased to 40 cm, there were still adults appeared and their emergence rate was 80%. The results of indoor trend test showed that the selectivity of orient fruit fly on fruits produced in Suzhou was sequenced from high to low as follows： tangerine, dates, pomegranate, peach, orange, pear and persimmon. While the sequence of fruit tree species were tangerine, dates, pomegranate, pears and persimmons according to damage rates of orient fruit fly from high to low under field isolation rearing conditions. In the local tangerine varieties, the damage rate from high to low were Dongting manda- rin, eady tangerine, Wen orange, Huangpi, Zaohong, Liaohong. [ Conclusion] Orient fruit fly artificial rearing facility was established, which laid the foundation for carrvina out bioloaical characteristics observation and biolooical exoeriments

Effects of Aquatic Plants on the Feature of Sediment Resuspension in Lake Taihu

[Objective] The aim was to study effects of aquatic plants on resuspen- sion of sediment in Lake Taihu. [Method] New resuspension simulator was used in the research. Elodea nuttalli, submerged plant, and Phragmites australis, emergent aquatic plant, were grown in substrate sludge with varied planting density set. Study of simulation experiment on the feature of sediment resuspension was carried on under shearing stress of 0.2-0.5 N/m2 and agitation of 1-30 min. [Result] Aquatic plant growing would effectively reduce seston concentration in water. Concentrations of final Suspended Particulate Matter （SPM） in experimental groups and control groups were as follows： water without plant〉coverage of 30% of Elodea nuttalli〉cov- erage of 60% of Elodea nuttalli〉Phragmites australis with concentration of 50 stock/m2〉 coverage of 90% of Elodea nuttalli〉Phragmites australis with concentration of 80 stock/m2〉Phragmites australis with concentration of 150 stock/m2; SPM concentration showed a tendency from increasing to stable with change of stirring time under dif- ferent shearing stresses： SPM concentration was of severe change at early stage in barrel without aquatic plant while change of SPM concentration in barrel with aquatic plant was quite mild and grew smaller with concentration increasing; SPM concentration was reduced much more if Phragmites australis planted compared with that of Elodea nuttalli; under different shearing stresses, reduction of SPM concen- tration by increase of Phragmites australis area was much more than by increase of Elodea nuttalli area. [Conclusion] It would provide powerful scientific reference for control on aquatic environment through comprehensive research on the feature of sediment resuspension.

Maintaining healthy rivers and lakes through water diversion from Yangtze River to Taihu Lake in Taihu Basin

On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtz,e River to Taihu Lake in solving the water problem and establishing a harmonious eco-environment in the Taihu Basin is performed. The water quantity and water quality conjunctive dispatching ＇decisi＂ofi-makifig support system, which ensures flood control, water supply and eco-aimed dispatching, is built by combining the water diversion with flood control dispatching and strengthening water resources monitoring and forecasting. With the practice and effect assessment, measures such as setting the -integrated basin management format, further developing water diversion and improving the hydraulic engineering projects system and water monitoring system are proposed in order to maintain healthy rivers and guarantee the development of the economy and society in the Taihu Basin.

Sediment transport following water transfer from Yangtze River to Taihu Basin

To meet the increasing ：need of fresh water and to improve the water quality of Taihu Lake, water transfer from the Yangtze River was initiated in 2002. This study was performed to investigate the sediment distribution along the river course following water transfer. A rainfall-runoff model was first built to calculate the runoff of the Taihu Basin in 2003. Then, the flow patterns of river networks were simulated using a one-dimensional river network hydrodynamic model. Based on the boundary conditions of the flow in tributaries of the Wangyu River and the water level in Taihu Lake, a one-dimensional hydrodynamic and sediment transport numerical model of the Wangyu River was built to analyze the influences of the inflow rate of the water transfer and the suspended sediment concentration （SSC） of inflow on the sediment transport. The results show that the water transfer inflow rate and SSC of inflow have significant effects on the sediment distribution. The higher the inflow rate or SSC of inflow is, the higher the SSC value is at certain cross-sections along the ：river course of water transfer. Higher inflow rate and SSC of inflow contribute to higher sediment deposition per kilometer and sediment thickness. It is also concluded that a sharp decrease of the inflow velocity at the entrance of the Wangyu River on the river course of water transfer induces intense sedimentation at the cross-section near the Changshu hydro-junction. With an increasing distance from the Changshu hydro-junction, the sediment deposition and sedimentation thickness decrease gradually along the river course.

Representation of Regional Culture, Spirit of Place and Landscape——Landscape Design of International Conference Center of Taihu Forum,Suzhou

Regional culture and spirit of place is the key and soul of landscape design, without which the landscape design would lose its vitality. Landscape design of Taihu Forum is focused on the discussion upon regional culture and spirit of place.

Research on Survival Conditions of Bellamya sp.in Different Aquatic Vegetation Habitats in Taihu Area

[Objective] The paper was to investigate the survival conditions of Bel- lamya sp. in different aquatic vegetation habitats in Taihu area, so as to provide suitable evaluation indexes for environmental monitoring in the area. [Method] Equal density of Bellamya sp. was placed in 3 aquatic vegetation habitats （emerged plant area, submerged plant area and non-plant area） in ecological engineering construc- tion area near the west of Wangyuhe in Taihu, the survival rate, SOD activity, MDA content and P450 enzyme activity of Bellamya sp. during outbreak and non-outbreak stage of cyanobacteria were determined, and the correlation between these indexes and ammonia nitrogen content of lake water was also analyzed. [Result] During the outbreak stage of cyanobacteria, the survival rates of Bellamya sp. in emerged plant area, submerged plant area and non-plant area were 0%, 55.2% and 89.3%, re- spectively, SOD activity first decreased and then increased, the change trend of MDA content was opposite with SOD change trend, P450 enzyme activity continu- ously decreased. During non-outbreak stage of cyanobacteria, the survival rates of Bellamya sp. in 3 habitats were 90.6% ,98.8 and 99.5%, respectively, SOD activity first decreased and then increased, MDA content first increased and then decreased, the changes of P450 enzyme activity were not regular. SOD activity of Bellamya sp. during 2 phases had significantly negative correlation with ammonia nitrogen content of lake water, MDA content had significantly positive correlation with ammonia nitro- gen content of lake water only during non-outbreak stage of cyanobacteria, P450 enzyme activity has no significant correlation with ammonia nitrogen content. This in- dicated that when Bellamya sp. was used to evaluate the impact of aquatic vegeta- tion on benthic animals, P450 enzyme activity was not the suitable indicator. [Conclusion] SOD activity in muscle tissue of Bellamya sp. could be used as the indica- tor for evaluation of habitat, MDA could be used as indicator for detection of am- monia nitrogen content during non-outbreak stage of cyanobacteria, P450 enzyme could not be used as the indicator for early diagnosis and early warning of environ- mental pollution in 3 habitats in Taihu area.

Expression of GHR, IGF-I, IGF-IR and IGFBP-3 Genes in Leg Muscles of Taihu Goose and Wanxi White Goose and Correlation between Their Expression and Carcass Traits

[Objective] This study aimed to explore the effects of IGFs system on the growth of goose skeletal muscles. [Method] Quantitative fluorescence PCR technique was adopted to study the variety- and gender-specificity in the expression of GHR, IGF-I, IGF-IR and IGFBP-3 genes in leg muscles of 70-day-old Taihu goose and Wanxi white goose, and the correlation between their expression and carcass traits was also investigated. [Resull] There was no variety difference in the expression of GHR, IGF-t, IGF-IR and IGFBP-3 genes in leg muscles of Taihu goose and Wanxi white goose, but there were significant variety differences in the body weight and leg muscle weight. There were no gender difference in the body weight, leg muscle weight and the rate of leg muscles; except IGF-I mRNA level that was significantly higher in male Taihu goose than in female ones（P=0.032）, there was no gender dif- ference in the expression of other three genes. Among the four tested genes, only IGFBP-3 mRNA exhibited an extremely significantly positively correlation with the rate of leg muscles, suggesting that IGFs may play a role in regulating the growth of leg muscles via IGFBP-3 system in 70-day-old goose. [Conclusion] This study provides theoretical basis for research in the skeletal growth and development.

Environmental abundance and microcystin-LR production ability of toxic Microcystis in Nanquan region of Lake Taihu

The variations of environmental abundance and microcystin-LR （MC-LR） production ability of toxic Microcystis in the Nanquan region of Lake Taihu are investigated by real-time quantitative PCR （RTQ-PCR） and high performance liquid chromatography （HPLC） from May to December in 2009. Simultaneously, degrees of water pollution and eutrophication are monitored. The results indicate that the water quality in the Nanquan region of Lake Taihu is in a moderate degree of pollution and eutrophication. Algal density exceeds the threshold of bloom from May to November. The environmental abundance of toxic Microcystis is more than 40% from May to October and then significantly declines to 5.66% due to the obvious reduction in the water temperature in December. From May to December, the MC-LR production ability of toxic Microcystis ranges from 1.661 to 9.293 μg/108cells. With the significant drops in water temperature and algal density, the MC-LR production ability of toxic Microcystis is obviously increased from November to December. It is concluded that the lake presents Microcystis bloom and the toxic Microcystis becomes dominant during most of the year. The environmental abundance and the MC-LR production ability of toxic Microcystis have a close relationship with water temperature. The effective control of toxic Microcystis should be considered in both the bloom period and the non-bloom period of winter since the MC-LR production ability of toxic Microcystis obviously increases in winter.

太湖不同生态型湖区湖鲚(Coilia ectenes taihuensis)食物组成及其季节变化

利用单船表层单囊拖网于2013年2 12月分别在太湖不同生态型湖区（敞水湖区和草型湖区）采集湖鲚（Coilia ectenes taihuensis）样品,同时用刺网补充大个体样品.通过胃含物鉴定,分析湖鲚饵料生物的种类及数量季节和湖区间差异,同时测定湖鲚摄食率、肥满度和食物选择系数等.结果显示,湖鲚主要食物为浮游枝角类和桡足类,此外,水生昆虫、轮虫和小型鱼虾也是湖鲚的重要食物来源.湖鲚食物组成季节变化明显,冬季以桡足类的哲水蚤（Calanus spp.）、剑水蚤（Cyclops spp.）为主,夏、秋季则以枝角类的象鼻溞（Bosmina spp.）、裸腹溞（Moina spp.）和盘肠溞（Chydorus spp.）为主.不同湖区湖鲚食物种类差异明显,草型湖区水生昆虫、鱼虾较敞水湖区多,桡足类较敞水湖区少.不同湖区间湖鲚食物数量差异明显,敞水湖区湖鲚平均食物数量为788.98±262.4 ind./尾,而草型湖区仅为298.85±71.1 ind./尾.湖鲚主动摄食大型枝角类,如僧帽溞（Daphnia cucullata）、低额溞（Simocephalus spp.）和大型溞（Daphnia magna）,选择指数（Ii）介于0.59~1.00之间.

Phosphorus fractionation and bio-availability in Taihu Lake(China) sediments

Typical sediments from Taihu Lake, a meso-to-hypereutrophic lake, were collected and examined on the basis of P-fractionation by sequential extraction scheme. Sedimentary inorganic phosphorus were fractioned into four forms and the rank order according to the mean concentration of P-fractions in Taihu Lake was NaOH-P>BD-P>HCl-P>NH_4Cl-P. The concentrations of BD-P were linearly correlated with the content of active Fe(R2=0.96). Also, the linear relationship between the sum of BD-P and NaOH-P and the sum of active Fe and active Al content was observed within the six sediments investigated(R2=0.96). Moreover, the bio-available phosphorus(BAP) content was estimated by the sum of NH_4Cl-P, BD-P, and NaOH-P, viz. BAP=NH_4Cl-P+NaOH-P+BD-P. In Taihu Lake, the BAP contents are ranging from 0.10 mg/g dw to 1.25 mg/g dw, and average 0.40 mg/g dw for all sediment samples. The relative contributions of BAP to total sedimentary phosphorus(TP) and inorganic sedimentary phosphorus(IP) range from 18.67% to 50.79%(33.61% on average) and from 52.82% to 82.09%(67.81% on average), respectively.

Effects of hydrodynamics processes on phosphorus fluxes from sediment in large,shallow Taihu Lake

The turnover of phosphorus （P） in lake sediments, a major cause of eutrophication and subsequent deterioration of water quality, is in need of deep understanding. In this study, effects of resuspension on P release were studied in cylindrical microcosms with Yshape apparatus. The results indicated that there was a positive correlation between flux of suspended substance across sediment-water interface （Fss） and the wind speed, and an increasing Fss during each wind process followed by a steady state. The maximal Fss under fight, moderate, and strong wind conditions were 299.9±41.1,573.4±61.7, and 2093.8±215.7 g/m^2, respectively. However, flux of P across sediment-water interface （Fp） did not follow a similar pattern as Fss responding to wind intensity, which increased and reached the maximum in initial 120 rain for fight wind, then decreased gradually, with maximal flux of 9.4±1.9 mg/m^2. A rapid increase of Fp at the first 30 rain was observed under moderate wind, with maximal flux of 11.2±0.6 mg/m^2. Surprisingly, strong wind caused less Fp than under light and moderate wind conditions with maximal flux of 3.5±0.9 mg/m^2. Fss in water column declined obviously during the sedimentation process after winds, but Fp varied with wind regime. No obvious difference was detected on Fp after 8 h sedimentation process, compared with the initial value, which means little redundant P left in the water column after winds.

太湖贡湖湾鲚(Coilia ectenes taihuensis Yen et Lin)食物组成的季节变化

鲚(Coilia ectenes taihuensis Yen et Lin)是太湖主要的鱼类之一,其产量随水体富营养化程度的加重呈上升趋势.本研究于2009年4-12月用刺网(a=10 mm)在太湖贡湖湾采集了鲚,分析了其胃含物中食物组成的季节变化以及鲚对食物种类的选择性.结果表明,鲚在各月中主要以浮游动物为食,同时也摄食幼鱼、幼虾和水生昆虫等.鲚的食物组成具有明显季节变化,4月份以桡足类为食,其中桡足幼体、汤匙华哲水蚤(Sinocalanus dorrii Brehm)和剑水蚤(Cyclops spp.)所占的平均个数百分比相当;6、8和10月份主要以枝角类为食,其中6月以裸腹溞(Moina spp.)为主,而8和10月以象鼻溞(Bosmina spp.)为主.食物选择性方面,鲚对大型浮游动物表现出主动选择;当环境中出现溞(Daphnia spp.)和透明薄皮溞(Leptodora kindti Focke)时,鲚对它们表现出很强的选择性摄食,但透明薄皮溞只出现在6月鱼类食物中;个体较小的裸腹溞也是鲚主动选择的重要食物,在整个调查期间鲚对裸腹溞都表现出较高的主动选择性;象鼻溞虽然在各月份食物中的出现率最高,但除10月份鲚对其表现出主动选择外,其它月份表现为主动回避或随机选择.本研究结果有助于我们了解鲚对浮游动物群落影响的季节变化,为制定合理的湖泊与渔业管理方案提供依据.

Seasonal variation of Microcystis in Lake Taihu and its relationships with environmental factors

In order to monitor the changes of Microcystis along with temporal and spatial variations, seasonal variation of Microcystis in Lake Taihu was investigated by 16S-23S rRNA internal transcribed spacer denaturing gradient gel electrophoresis （16S-23S rRNA-ITS DGGE） and microscopic evaluation. Samples were collected quarterly at four sites （River Mouth, Meiliang Bay, Cross Area, and Lake Center） from August 2006 to April 2007. Results showed that Microcystis dominated total phytoplankton abundance at the four sites in all seasons except winter. The average annual abundance of Microcystis was relatively high at River Mouth and Meiliang Bay, reaching 81.22×10^6 and 61.32×10^6 cells/L, respectively. For temporal variations, Shannon-Wiener diversity index （H＇） according to DGGE profile revealed the richness of Microcystis in summer （H＇ = 1.375±0.034） and winter （H＇ = 1.650 ±0.032） was lower than that in spring （H＇ = 2.078 ±0.031） and autumn （H＇ = 2.365 ±0.032） （P 〈 0.05）. While for spatial variations, the richness of Microcystis at River Mouth （H＇ = 2.015± 0.074） was higher than at other sites during four seasons （P 〈 0.01）. Very few differences of Microcystis diversity in the same season were observed among the other three sites （P 〉 0.05）. Canonical correspondence analysis （CCA） was performed to elucidate the relationships between Microcystis operational taxonomic units （OTUs） composition and the environmental factors. Results of CCA revealed that temperature was strongly positively correlated with the first axis （r = 0.963）, while TSS was negative correlated with the second axis （r = -0.716）. Phylogenetic tree based on the sequencing results of target bands on DGGE gel indicated that samples collected in summer and winter constituted two separated clusters.

Nitrogen interception in floodwater of rice field in Taihu region of China

A field experiment located in Taihu Lake Basin of China was conducted, by application of urea or a mixture of urea with manure, to elucidate the interception of nitrogen （N） export in a typical rice field through ＂zero-drainage water management＂ combined with sound irrigation, rainfall forecasting and field drying. N concentrations in floodwater rapidly declined before the first event of field drying after three split fertilizations, and subsequently tended to rearm to the background level. Before the first field drying, total particulate nitrogen （TPN） was the predominant N form in floodwater of plots with no N input, dissolved inorganic nitrogen （DIN） on plots that received urea only, and dissolved organic nitrogen （DON） on plots treated with the mixture of urea and manure. Thereafter TPN became the major form. No N export was found from the rice field, but total nitrogen （TN） of 15.8 kg/hm^2 was remained, mainly due to soil N sorption. The results recommended the zero-drainage water management for full-scale areas for minimizing N export.

Identification of anthropogenic influences on water quality of rivers in Taihu watershed

Surface water bodies are progressively subjected to stress as a result of anthropogenic activities. This study assessed and examined the impact of human activities on spatial variation in the water quality of 19 rivers in the Taihu watershed. Concentrations of physicochemical parameters of surface water quality were determined at the mouth of each river during the period of 2000-2004. Multivariate statistical techniques were applied to identify characteristics of the water quality in the studied rivers. The results showed that rivers strongly influenced by household wastewater have the highest concentrations of nutrients （TN and TP）. Moreover, rivers in the vicinity of a metropolis presented low dissolved oxygen （DO） levels. However, organic-chemical pollution （petroleum and volatile phenolics） was identified with high localization. Two rivers influenced by sewage from industry and ships were distinguished from other rivers with high values of petroleum. The Taige channel, a river located in Changzhou City that is strongly influenced by wastewater from industry, was characterized with an extraordinarily high value of volatile phenolics. Rivers passing through countries, especially through hilly countries were characterized with high DO contents and low nutrient and organic-chemical pollution, suggesting that agriculture puts less pressure on water quality in adjacent rivers. Therefore, more effort should be made in controlling point pollution to restore water quality in rivers adjacent to cities.

Bioaccumulation of heavy metals in fishes from Taihu Lake,China

The Cr, Zn, Cu, Cd, Pb contents were determined in Cyprinus carpio Linnaeus, Carassius auratus Linnaeus, Hypophthalmichthys molitrix and Aristichthys nobilis, which were caught from Meiliang Bay, Taihu Lake, a large, shallow and eutrophic lake of China. The results showed that： （1） the Cr, Cu, Pb, Cd contents in the edible parts of the four fish species were much lower than Chinese Food Health Criterion （1994）, but the Zn contents were higher than the Criterion; （2） Cd contents were the highest in the liver of fish, Pb contents were almost the same in all organs of fish, Cr contents mainly enriched in the skin and gonads, Zn contents were the highest in the gonad （♀）, and Cu contents were the highest in the liver; （3） the total metal accumulation was the greatest in the liver and the lowest in the muscle. The total metal accumulation was the highest in C. auratus L. This investigation indicated that fish products in Taihu Lake were still safe for human consumption, but the amount consumed should be controlled under the Chinese Food Health Criterion to avoid excessive intake of Zn.

Three-dimensional eutrophication model and application to Taihu Lake,China

Taihu Lake, the largest freshwater shallow lake in eastern China, has suffered from severe eutrophication over the past two decades. This research developed a three-dimensional eutrophication model to investigate the eutrophication dynamics. The model fully coupled the biological processes and hydrodynamics, and also took into account the effects of sediment release and the external loads from the tributaries. After sensitivity analyses, the key parameters were defined and then calibrated by the field observation data. The calibrated model was applied to study the seasonal primary productions and its regional differences. The comparisons between model results and field data in year 2000 indicated that the model is able to simulate the eutrophication dynamics in Taihu Lake with a reasonable accuracy. From the simulation experiments, it was found that the meteorological forcing have significant influences on the temporal variations of the eutrophication dynamics. The wind-induced circulation and sediment distribution play an important role in the spatial distribution of the algae blooms.

Composition analysis of colored dissolved organic matter in Taihu Lake based on three dimension excitation-emission fuorescence matrix and PARAFAC model, and the potential application in water quality monitoring

Taihu Lake is one of the five biggest lakes in China. Surface water samples from 26 sampling sites of Taihu Lake were collected. Furthermore wet chemical analysis （CODCr and BOD5） and measurement of three dimensional excitation-emission matrix （3DEEM） spectra in the laboratory have been conducted. Using parallel factor analysis （PARAFAC） model, three components of colored dissolved organic matter （CDOM） have been identified successfully, based on the analysis of 3DEEM data. The characteristics of the three components also have been described by comparing them to some components of CDOM, identified in earlier researches. Meanwhile, spatial variations of concentration for the three components in Taihu Lake have been analyzed, and the result indicates that the concentration of component 1 depends more on the situation of wastewater pollution and can be used as the indicator of wastewater pollution. The relationship between the concentrations of the three components and results of the wet chemical analysis show that none of the three components can be used as indicators of gross organic matter in water. However, the concentrations of all the three components have obvious linear relationships with the BOD5 value, especially for component 1 （r = 0.72878）. Finally, the potential applications of the composition analysis based on 3DEEM and PARAFAC model in water quality monitoring have been illuminated.

Sediment distribution pattern mapped from the combination of objective analysis and geostatistics in the large shallow Taihu Lake, China

Investigation was made into sediment depth at 723 irregularly scattered measurement points which cover all the regions in Taihu Lake, China. The combination of successive correction scheme and geostatistical method was used to get all the values of recent sediment thickness at the 69×69 grids in the whole lake. The results showed that there is the significant difference in sediment depth between the eastern area and the western region, and most of the sediments are located in the western shore-line and northern regimes but just a little in the center and eastern parts. The notable exception is the patch between the center and Xishan Island where the maximum sediment depth is more than 4.0 m. This sediment distribution pattern is more than likely related to the current circulation pattern induced by the prevailing wind-forcing in Taihu Lake. The numerical simulation of hydrodynamics can strong support the conclusion. Sediment effects on water quality was also studied and the results showed that the concentrations of TP, TN and SS in the western part are obviously larger than those in the eastern regime, which suggested that more nutrients can be released from thicker sediment areas.