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84篇 您的检索式:作者名="QIN BoQiang"
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1Lake eutrophication and its ecosystem response显示文摘China is a country with many lakes,about one-third of which are freshwater mainly distributed in the middle and lower reaches of the Yangtze River.Currently most of the lakes are mesotrophic or eutrophic.Lake eutrophication has become one of the major ecological and environmental problems faced by lakes in China and can lead to a series of abnormal ecosystem responses,including extinction of submerged plants,frequent occurrence of cyanobacterial blooms,increased microbial biomass and productivity,decreased biodiversity,accelerated cycles,and a change in the efficient use of nutrients.With development of eutrophication,the whole lake ecosystem suffers decreased biodiversity,simplification of biotic community structure,instability of the ecosystem,and ultimately the clear-water,macrophyte-dominated ecosystem gradually shifts to a turbid-water,algae-dominated ecosystem.This ecosystem succession mechanism is speculated to be caused by different nutrient utilization efficiencies of macrophytes and phytoplankton.The ultimate ecosystem succession trend of seriously eutrophic lakes is that a phytoplankton-dominated autotrophic lake shifts to a heterotrophic lake dominated by micro-organisms,protozoans.QIN BoQiang GAO Guang ZHU GuangWei ZHANG YunLin SONG YuZhi TANG XiangMing XU Hai DENG JianMing 2013Chinese Science Bulletin2013,58,9:63
2Why Lake Taihu continues to be plagued with cyanobacterial blooms through 10 years(2007–2017) efforts显示文摘With the expansion of urban, industry, and agriculture after World War II, eutrophication firstly emerged as a major water quality threat in small water bodies [1]. As the increasing magnitudes and scales of nutrient pollution and habitat alteration, many of the world's large lakes exhibit symptoms of eutrophication, e.g., toxic cyanobacterial blooms, deoxygenation, and habitat loss.Boqiang Qin Hans W.Paerl Justin D.Brookes Jianguo Liu Erik Jeppesen Guangwei Zhu Yunlin Zhang Hai Xu Kun Shi Jianming Deng 2019Science Bulletin2019,64,6:50
3Estimation of internal nutrient release in large shallow Lake Taihu, China显示文摘Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, China, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition),both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in sediments.As for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4+-N for whole lake is ca. 10,000 ton/a, and PO43--P is ca. 900 ton/a. In the dynamic condition, nutrient release following sediment suspension was estimated according to three different intensities of wind forcing which were defined as 'calm' (wind speed is less than 2 m/s), 'gentle' (wind speed is greater than 2 m/s and less than 6 m/s) and 'gust' (wind speed is greater than 6 m/s). The release rate in the condition of 'calm' was estimated in terms of the nutrient release in the laboratory experimental static condition; whereas the release rate in conditions of 'gentle' and 'gust' was estimated in terms of measurement during sediment resuspension conducted in flume experiments. With the observation of wind velocity and frequency in 2001, each type of wind forcing took the frequency of 12%, 82% and 6% for 'calm', 'gentle' and 'gust', respectively. The yearly release of nitrogen was 81,000 ton and phosphorus was 21,000 ton, which is about 2-6 folds of annual external loading, respectively.QIN Boqiang, ZHU Guangwei, ZHANG Lu, LUO Liancong, GAO Guang & GU Binhe Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Everglades Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL 33406, USA 2006Science China Earth Sciences2006,49,z1:37
4Mechanism and control of lake eutrophication显示文摘A review about lake naturally eutrophi- cating, the internal loading of nutrients from lake sediment as well as the mechanism of algal blooms and the control practices was made, especially the eutrophication problem of shallow lakes since sev- enty percent of fresh water lakes in China are shallow lakes. It was found that shallow lakes are apt toward eutrophication than deep lakes. Without any influ- ences of human activity, shallow lakes in the middle and lower reaches of Yangtze River are still easily eutrophicated, which may be owing to the effects of flood in this area. In shallow lakes, sediments are frequently disturbed by wind-wave and resuspended, which result in huge nutrients release to overlying water. This may be the major reason for higher in- ternal loading of nutrients in shallow lakes than in deep lakes. Algal bloom is an extreme response of lake ecosystem to the eutrophication. Appearance of algal blooms is related to physical condition of lakes, such as underwater radiation (or transparency), temperature, and hydrodynamic conditions, or related to geochemical conditions of lakes, like concentra- tions of nutrients and ratio of nitrogen to phosphorus, as well as the physiological advantage of cyanobac- teria such as vacuole for moving towards the radiant energy-rich zone and the mycosporine-like amino acids (MAAs) for resisting the harm of ultraviolet ra- diation. In shallow lakes, these advantages of cyanobacteria are favorable in the competition than in deep lakes. Also being the shallowness, it is more difficult to reduce nutrient loading and to control algae blooms in shallow lakes. For the control of eutrophi- cation, people should follow the sequence from pollution sources control, ecological restoration tocatchment management. To control the internal nu- trient release, physical, chemical, biological tech- niques, and even bionic techniques could be selected. The idea of ecological restoration for a eutrophic lake is to shift the ecosystem from phytoplankton-domi- nant state to macrophyte-dominant state. To realize the shift of ecosystem state, environmental condition improvement is the fundamental work. Nowadays, we should do more work on environmental condition improvement than on planting of macrophytes since we are lack of the knowledge about the relationship between macrophyte and lake ecosystem. Empha- sizing the macrophyte planting, therefore, has blind- ness at present. Because all lakes have different characteristics of environment and ecosystem, ap- plicable lake harness techniques should be selected based on the distinct ecosystem types and environ- mental problems.QIN Boqiang YANG Liuyan CHEN Feizhou ZHU Guangwei ZHANG Lu CHEN Yiyu 2006Chinese Science Bulletin2006,51,19:38
5The nutrient forms, cycling and exchange flux in the sediment and overlying water system in lakes from the middle and lower reaches of Yangtze River显示文摘This paper is a review of research works concerning the nutrient transportation,transformation and exchange between water, sediment and biota in the lakes from the middle and lower reaches of the Yangtze River conducted in the context of project entitled 'The Processes and Mechanism of Lake Eutrophication in Middle and Lower Reaches of Yangtze River'. All the lakes from this area are shallow lakes. According to the typical lake site research, the lakes from the middle and lower reaches of Yangtze River have a higher baseline of nutrition in the history. Normally the trophic status of these lakes can be categorized into medium-trophic or eutrophic. Human activities have been enhanced during the last decades, which speed up the lake eutrophic process. Lake eutrophication control needs to reduce not only the external nutrient inputs from watershed but also the internal loading from the sediments. Investigations revealed that the lake sediments in this area are considerablly high in nutrition in which at most about 30% of phosphorus exists in the form of bio-available in the sediment. The surface sediment will exert great effects on the nutrient exchange between water-sediment interface via adsorption and release of nutrient. The nutrient release from the sediment in these shallow lakes is mainly in two ways, i.e. in the undisturbed condition the nutrient is released through diffusion created by the nutrient gradient from sediment to overlying water; whereas in disturbed condition, the nutrient release is determined by the hydrodynamic forcing intensity and the sediment resuspension. Metallic elements such as the iron, manganese and aluminium and the aerobic-anaerobic ambience will affect the release of nutrients. The disturbed release will increase the total nutrients in the water column significantly in the short period. At the beginning of sediment resuspension, the dissolved nutrient concentration will increase. This increase will be damped if the ferric oxide and aluminium are rich in sediment because of the adsorption and flocculation. This means that the lakes have capability of eliminating the nutrient loadings. Investigations for the lakes from middle and down stream of Yangtze River have suggested that most lakes have the self-cleaning capability. Dredging the control of the internal loading, therefore, is only applicable to the small lakes or undisturbed bays which normally are situated nearby the city or town and rich in organic materials in the sediment. In addition, the strong reduction condition and weak aeration of these lakes and bays make these small lakes and bays release much more bio-available nutrient and without much self-eliminating capability. Moreover, eutrophication induced algal bloom in these lakes will change www. scichina.com www. springerlink.comthe pH of water, which further induces the increase in the nutrient release. In turn, the increase in nutrient release promotes the growth of phytoplankton and results in severe algal bloom. For the heavily polluted water, research suggests that the biomass of bacteria and alkaline phosphatase activity will be higher corresponding to the higher concentration of nutrients, which accelerates the nutrient recycling between water, sediment and biota. Quick recycling of nutrient, in turn, promotes the production and biomass growth of microorganism and leads to more severe eutrophication. Further research work should focus on the nutrient transformation mechanism and the effects of microbial loop on the eutrophication.QIN Boqiang ZHU Guangwei 2006Science China Earth Sciences2006,49,z1:22
6Controlling cyanobacterial blooms by managing nutrient ratio and limitation in a large hypereutrophic lake: Lake Taihu, China显示文摘Excessive nitrogen(N) and phosphorus(P) loading of aquatic ecosystems is a leading cause of eutrophication and harmful algal blooms worldwide, and reducing nutrient levels in water has been a primary management objective. To provide a rational protection strategy and predict future trends of eutrophication in eutrophic lakes, we need to understand the relationships between nutrient ratios and nutrient limitations. We conducted a set of outdoor bioassays at the shore of Lake Taihu. It showed that N only additions induced phytoplankton growth but adding only P did not. Combined N plus P additions promoted higher phytoplankton biomass than N only additions, which suggested that both N and P were deficient for maximum phytoplankton growth in this lake(TN:TP = 18.9). When nutrients are present at less than 7.75–13.95 mg/L TN and 0.41–0.74 mg/L TP, the deficiency of either N or P or both limits the growth of phytoplankton. N limitation then takes place when the TN:TP ratio is less than 21.5–24.7(TDN:TDP was 34.2–44.3), and P limitation occurs above this. Therefore, according to this ratio, controlling N when N limitation exists and controlling P when P deficiency is present will prevent algal blooms effectively in the short term. But for the long term, a persistent dual nutrient(N and P) management strategy is necessary.Jianrong Ma Boqiang Qin Pan Wu Jian Zhou Cheng Niu Jianming Deng Hailin Niu 2015Journal of Environmental Sciences2015,27,1:20
7Alkaline phosphatase activity and the phosphorus mineralization rate of Lake Taihu显示文摘The phosphorus fractions, the alkaline phosphatase activity (APA) and other water chemical parameters were concomitantly monitored from April 2003 to October 2004 in different ecotype sites of Lake Taihu. During the stages of algae growth, the phosphorus fractions and their relationships with APA in different ecotype sites were discussed and the phosphorus mineralization rate was calculated. In the water of Lake Taihu, most of the phosphorus (70.2%) could be attributed to the suspended particulate phosphorus, while the dissolved reactive phosphorus (DRP) seems to contribute less than 7%. About 58% of the total phosphorus, however, can be hydrolyzed as inorganic phosphate to compensate for phosphorus deficiency of algae and bacteria growth. During the different algae growth stages, the APA and its Kinetic parameters were varied significantly between different ecotype sites of Lake Taihu. This trend is also visible by comparing the phosphorus mineralization rate,and the most rapidly phosphorus turnover time is only several minutes. The fast recycle of phosphorus can, to some extent, be explained that the phosphorus source of algal blooms. The phytoplankton seems to compensate for phosphorus deficiency by using the alkaline phosphatase to hydrolyze phosphomonoesters.GAO Guang, ZHU Guangwei, QIN Boqiang, CHEN Jun & WANG Ke Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Hohai University, Nanjing 210098, China 2006Science China Earth Sciences2006,49,z1:18
8Effect of sediment resuspension on underwater light field in shallow lakes in the middle and lower reaches of the Yangtze River:A case study in Longgan Lake and Taihu Lake显示文摘Based on three continuous in situ underwater light field measurement under different wind waves conditions in Longgan Lake, Meiliang Bay of Taihu Lake in July 2003 and littoral zone near TLLER in July 2004, respectively, the effects of sediment resuspension caused by wind waves on PAR diffuse attenuation, absorption coefficients and euphotic depths are analyzed. In Longgan Lake, PAR diffuse attenuation coefficients during small, middle and large wind waves were 1.74, 2.02 and 2.45 m-1, respectively, and the corresponding PAR spectral diffuse attenuations ranged from 0.98 to 2.97, 1.34 to 3.95 and 1.80 to 5.40 m-1, respectively. In Meiliang Bay, PAR diffuse attenuation coefficients were 2.63, 3.72, 4.37 m-1 during small, middle and large wind waves. PAR diffuse attenuation coefficients increased by 41% and 66% from small to middle, large wind waves, respectively.Absorption coefficients integrated over the range of PAR of CDOM, phytoplankton were 0.26, 0.28 m-1;0.76, 0.49 m-1, respectively during middle and large wind waves. Absorption coefficients integrated over the range of PAR of non-algal particulate matter and total suspended particulate matter increased from 0.94 to 1.73 m-1, and from 1.70 to 2.22 m-1, respectively during middle and large wind waves. Relative contributions of absorption coefficients of non-algal particulate matter to total absorption coefficient integrated over the range of PAR were 44.14%, 65.05%, respectively, during middle and large wind waves. PAR euphotic depths decreased by 0.40, 0.19, 0.20 m from middle to large wind waves in Longganhu Lake, Meliang Bay and littoral zone near TLLER. Significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and total suspended particulate matter, wind velocity, wave height. Most significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and inorganic suspended particulate matter but low correlations for chlorophyll a, dissolved organic carbon. Increase of total suspended particulate matter, especially inorganic suspended particulate matter caused by wind waves was the dominant factor affecting underwater light field in shallow lakes in the middle and lower reaches of the Yangtze River based on observations at three stations.ZHANG Yunlin, QIN Boqiang, ZHU Guangwei, GAO Guang, LUO Liancong & CHEN Weimin Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Graduate School of Chinese Academy of Sciences, Beijing 100039, China 2006Science China Earth Sciences2006,49,z1:14
9The role of periphytes in the shift between macrophyte and phytoplankton dominated systems in a shallow,eutrophic lake (Lake Taihu,China)显示文摘Based on experiments of periphyte response to different trophic levels and their impact on macrophyte production,it was found that the periphyte biomass increased with the nutrient con-centrations. Increased trophic level and periphyte biomass resulted in decreased macrophyte photo-synthesis. It was suggested that the periphytes could cause resilience and hysteresis in the system shifts between macrophyte and phytoplankton domination. Other factors,such as fish farming,storm induced waves and mechanical destruction,and high water levels could be the perturbations during the system shifts,but these are not the key factors. Instead,the nutrient loading and periphyte abundance could determine the shift in lake ecosystem between macrophyte and phytoplankton domination. This finding could theoretically elucidate the mechanism of ecosystem shifts between macrophyte and phytoplankton domination.QIN Boqiang SONG Yuzhi GAO Guang 2006Science China(Life Sciences)2006,49,6:14
10Phosphorus forms and bioavailability of lake sediments in the middle and lower reaches of Yangtze River显示文摘Forms of phosphorus in sediments from 25 lakes in the middle and lower reaches of Yangtze River were analyzed by the sequential extraction procedure. Contents and spatial distrubution of algal available phosphorus (AAP) in sediments of Lake Taihu, the third largest freshwater lake of China, were also studied. Relationships between phosphorus forms in sediment and macrophytes coverage in sample sites, as well as phosphorus forms in sediments and chlorophyal contents in lake water were discussed. Exchangeable form of phosphorus (Ex-P) in surface sediments was significantly positive correlative to total phosphorus (TP), dissolved total phosphorus (DTP) and soluble reactive phosphorus (SRP) contents in the lake water. Bioavailable phosphorus (Bio-P) contents in sediments from macrophytes dominant sites were significantly lower than that in no macrophyte sites. In Lake Taihu, Ex-P content in top 3 cm sediment was highest.However, content of ferric fraction phosphorus (Fe-P) was highest in 4-10 cm. Bioavalilble phosphorus (Bio-P) contents in surface sediments positively correlated to Chlorophyll a contents in water of Lake Taihu with significant difference. Therefore, contents of Bio-P and AAP could be acted as the indicators of risks of internal release of phosphorus in the shallow lakes. It was estimated that there were 268.6 ton AAP in top 1 cm sediments in Lake Taihu. Sediment suspension caused by strong wind-induced wave disturbance could carry plenty of AAP into water in large shallow lakes like Lake Taihu.ZHU Guangwei QIN Boqiang ZHANG Lu 2006Science China Earth Sciences2006,49,z1:12
11Experimental study on phosphorus release from sediments of shallow lake in wave flume显示文摘Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3 times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ situation.This study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.SUN Xiaojing,ZHU Guangwei, LUO Liancong & QIN Boqiang Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Graduate School of Chinese Academy of Sciences, Beijing 100039, China 2006Science China Earth Sciences2006,49,z1:12
12Phytoplankton community from Lake Taihu,China,has dissimilar responses to inorganic and organic nutrients显示文摘To evaluate the response of phytoplankton from Lake Taihu to different types of nutrients,the phytoplankton responses were measured after adding inorganic nitrogen(N) and phosphorus(P) or decomposed algal scum(Microcystis spp.) into the lake water. Both types of nutrients promoted an increase in phytoplankton biomass as determined by chlorophyll a and algal wet weight.The addition of decomposed algal scum resulted in a significantly greater phytoplankton response than the addition of inorganic N and P alone.The dissolved inorganic N and P in the inorganic nutrient treatment were found not limit phytoplankton growth.The higher algal biomass obtained in the treatment with decomposed algal scum indicated the importance of other organic nutrients besides N and P such as trace elements,as well as the importance of the form of N since the levels of ammonia nitrogen(NH4+-N) from the decomposed algal treatment were actually higher than that of the inorganic N and P addition.Microcystis spp.(Cyanobacteria) ,Scenedesmus spp.(Chlorophyta) and Synechocystis spp.(Cyanobacteria) were the dominant taxa in the control,inorganic N and P treatment,and the decomposed algal scum treatment,respectively.Microcystis never bloomed in response to both types of nutrient additions indicating that the bloom propagation is not solely related to nutrient additions,but may be related to the absence of selective grazing from zooplankton.Xiaodong Wang Boqiang Qin Guang Gao Yongping Wang Xiangming Tang Timothy Otten 2010Journal of Environmental Sciences2010,22,10:11
13Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects显示文摘The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective.Fahu CHEN Bojie FU Jun XIA Duo WU Shaohong WU Yili ZHANG Hang SUN Yu LIU Xiaomin FANG Boqiang QIN Xin LI Tingjun ZHANG Baoyuan LIU Zhibao DONG Shugui HOU Lide TIAN Baiqing XU Guanghui DONG Jingyun ZHENG Wei YANG Xin WANG Zaijun LI Fei Wang Zhenbo HU Jie WANG Jianbao LIU Jianhui CHEN Wei HUANG Juzhi HOU Qiufang CAI Hao LONG Ming JIANG Yaxian HU Xiaoming FENG Xingguo MO Xiaoyan YANG Dongju ZHANG Xiuhong WANG Yunhe YIN Xiaochen LIU 2019Science China Earth Sciences2019,62,11:11
14Response of community composition and biomass of submerged macrophytes to variation in underwater light, wind and trophic status in a large eutrophic shallow lake显示文摘Light climate is of key importance for the growth, community composition of submerged macrophytes in lakes and, they, in turn, are affected by lake depth and the degree of eutrophication. To test the relationships between submerged macrophyte presence and the ratio of Secchi disk depth(SDD) to water depth, i.e. SDD/depth, nutrients and wind, we conducted an extensive sampling campaign in a macrophyte-dominated area of the eastern region( n = 36) in 2016 in Lake Taihu, China, and combined the data gathered with results from extensive physico-chemical monitoring data from the entire lake. We confirmed that SDD/Depth is the primary factor controlling the community composition of macrophytes and showed that plant abundance increased with increasing SDD/Depth ratio( p < 0.01), but that only SDD/Depth > 0.4 ensured growth of submerged macrophytes. Total phosphorus and total nitrogen also influenced the growth and community composition of macrophytes( p < 0.01), while Chl a was an indirectly affecting factor by reducing underwater light penetration. Wave height significantly influenced plant abundance( p < 0.01), whereas it had little effect on the biomass( p > 0.05). The key to restore the macrophyte beds in the lake is to reduce the nutrient loading. A decrease of the water level may contribute as well in the shallow bays but will not bring plants back in the main part of the lake. As the tolerance of shade and nutrients varied among the species studied, this should be taken into account in the restoration of lakes by addition of plants.Baili Dong Yongqiang Zhou Erik Jeppesen Kun Shi Boqiang Qin 2021Journal of Environmental Sciences2021,33,5:10
15Vertical diversity of sediment bacterial communities in two different trophic states of the eutrophic Lake Taihu, China显示文摘Vertical diversity of sediment bacterial communities in 2 different trophic states(macrophyte-dominated and algae-dominated) of the large shallow eutrophic Lake Taihu,China,were investigated using denaturing gradient gel electrophoresis(DGGE) and 16S rRNA sequence analysis.Clustering analysis of DGGE profiles showed that different clusters were recognized in different depths of sediment cores in the 2 lake trophic states.Analyses of the bacterial diversity,as estimated by the Shannon index(H '),showed that different sediment layers of the macrophyte-dominated state had higher diversity than the algae-dominated state.In addition,bacterial diversity of the sediment in the macrophyte-dominated state changed abruptly throughout the layers,but bacterial diversity of the algae-dominated state decreased gradually with sediment depth.Phylogenetic analysis showed that Proteobacteria was the most abundant phylum in the middle sediment of the 2 lake trophic states.In the macrophyte-dominated state,clone sequences related to Betaproteobacteria(50.0%) were the most abundant,followed by Epsilonproteobacteria(21.1%),Acidobacteria(7.9%),Deltaproteobacteria(7.9%),Chloroflexi(7.9%),and Bacteroidetes(5.3%);whereas in the algae-dominated state,sequences affiliated with Betaproteobacteria(84.4%) were predominant,followed by Deltaproteobacteria(12.5%) and Acidobacteria(3.1%).Canonical correspondence analysis showed that organic matter and pH play key roles in driving the vertical changes of bacterial community composition.Keqiang Shao Guang Gao Yongping Wang Xiangming Tang Boqiang Qin 2013Journal of Environmental Sciences2013,25,6:9
16Pathogenic mechanisms and control strategies of Botrytis cinerea causing post-harvest decay in fruits and vegetables显示文摘Botrytis cinerea is a significant necrotrophic plant pathogen causing devastating diseases on more than 500 plant species,especially on fresh fruits and vegetables,resulting in the economic losses ranging from$10 billion to$100 billion worldwide.This fungal pathogen invades nearly all parts of plants including stems,leaves,flowers,fruits,and seeds at both pre-harvest and post-harvest stages.Due to its wide host range and the huge economic losses that it causes,extensive investigations have been carried out to effectively control this plant pathogen.It is beneficial for exploring the pathogenic mechanisms of B.cinerea to provide fundamental basis for control strategies.In recent years,tremendous progress has been made in understanding these pathogenic genes and regulatory pathways,as well as the control strategies of B.cinerea.Here,the current knowledge will be summarized in this review.Li Hua Chen Yong Zhang Zhanquan Li Boqiang Qin Guozheng Tian Shiping 2018Food Quality and Safety2018,2,3:8
17Nutrient fluxes induced by disturbance in Meiliang Bay of Lake Taihu显示文摘A wave flume experiment was conducted to study nutrient fluxes at water-sediment interface of Meiliang Bay under different hydrodynamic conditions. The results reveal that hydrodynamics has remarkable effects on nutrient fluxes in this area. With a bottom wave stress of 0.019 N m-2 (equivalent to disturbance caused by wind SE 5-7 m s-1 at the sediment sample site of Meiliang Bay), the fluxes of TN, TDN and NH4+-N were separately 1.92× 10-3, -1.81 × 10-4 and 5.28× 10-4 mg m-2 s-1(positive for upward and negative for downward), but for TP, TDP and SRP, the fluxes were 5.69 × 10-4, 1.68 × 10-4 and -1.29 × 10-4 mgm-2 s-1. In order to calculate the released amount of nutrients based on these results, statistic analysis on the long-term meteorological data was conducted.The result shows that the maximum lasting time for wind SE 5-7 m s-1 in this area is about 15 h in summer. Further calculation shows that 111 t TN, 32 t NH4+-N, 34 t TP and 10 t TDP can be released into water (the sediment area was 47.45% of the whole surface area), resulting in concentration increase of 0.025, 0.007, 0.007 and 0.002 mg L-1 separately. With stronger disturbance (bottom wave stress is 0.217 N m-2 which is equivalent to disturbance caused by wind SE 10-11 m s-1 at the same site), there has been significant increase of nutrient fluxes (1.16× 10-2, 6.76×10-3, 1.14× 10-2 and 2.14× 10-3 mgm-2 s-1 for TN, DTN and NH4+-N and TP). The exceptions were TDP with flux having a decrease (measured to be 9.54× 10-5 mgm-2 s-1 ) and SRP with flux having a small increase (measured to be 5.42 × 10-5 mgm-2 s-1). The same statistic analysis on meteorological data reveal that the maximum lasting time for wind SE 10-11 m s-1 is no more than 5 h. Based on the nutrient fluxes and the wind lasting-time, similar calculations were also made suggesting that 232 t TN, 134.9 t TDN, 228 t NH4+-N, 42.7 t TP, 2.0 t TDP and 1.1 t SRP will be released from sediment at this hydrodynamic condition resulting in the concentration increases of 0.050, 0.029, 0.049, 0.009, 0.0004 and 0.0002 mg L-1. Therefore in shallow lakes, surface disturbance can lead to significant increase of nutrient concentrations although some components in water column had negative flux with weak disturbance (e.g. TDN and SRP in this experiment). In this case, sediment looks to be a source of nutrients. These nutrients deposited in sediment can be carried or released into water with sediment resuspension or changes of environmental conditions at water-sediment interface, which can have great effects on aquatic ecosystem and is also the characteristics of shallow lakes.LUO Liancong, QIN Boqiang, ZHU Guangwei, SUN Xiaojing, HONG Dalin, GAO Yajun & XIE Rui Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Nanjing Hydraulic Research Institute, Ministry of Water Resources, Nanjing 210024, China 2006Science China Earth Sciences2006,49,z1:7
18Remote sensing of cyanobacterial blooms in inland waters: present knowledge and future challenges显示文摘Timely monitoring, detection and quantification of cyanobacterial blooms are especially important for controlling public health risks and understanding aquatic ecosystem dynamics. Due to the advantages of simultaneous data acquisition over large geographical areas and high temporal coverage, remote sensing strongly facilitates cyanobacterial bloom monitoring in inland waters. We provide a comprehensive review regarding cyanobacterial bloom remote sensing in inland waters including cyanobacterial optical characteristics, operational remote sensing algorithms of chlorophyll, phycocyanin and cyanobacterial bloom areas, and satellite imaging applications. We conclude that there have many significant progresses in the remote sensing algorithm of cyanobacterial pigments over the past 30 years. The band ratio algorithms in the red and near-infrared(NIR) spectral regions have great potential for the remote estimation of chlorophyll a in eutrophic and hypereutrophic inland waters, and the floating algae index(FAI) is the most widely used spectral index for detecting dense cyanobacterial blooms. Landsat, MODIS(Moderate Resolution Imaging Spectroradiometer) and MERIS(MEdium Resolution Imaging Spectrometer) are the most widely used products for monitoring the spatial and temporal dynamics of cyanobacteria in inland waters due to the appropriate temporal, spatial and spectral resolutions. Future work should primarily focus on the development of universal algorithms, remote retrievals of cyanobacterial blooms in oligotrophic waters, and the algorithm applicability to mapping phycocyanin at a large spatial-temporal scale. The applications of satellite images will greatly improve our understanding of the driving mechanism of cyanobacterial blooms by combining numerical and ecosystem dynamics models.Kun Shi Yunlin Zhang Boqiang Qin Botian Zhou 2019Science Bulletin2019,64,20:6
19A vertically integrated eutrophication model and its application to a river-style reservoir-Fuchunjiang,China显示文摘Based on a 2-D hydrodynamic model,a vertically integrated eutrophication model was developed.The physical sub-model can be used for calculation of water density at different depths,and the water quality sub-model was used for calculation of algal growth.The cohesive and non-cohesive sediments were simulated separately with different methods.The light extinction coeffcient used in the underwater light regime sub-model was linearly related to the sum of sediment and phytoplankton biomass.Some components less important to the model were simplified to improve practicability and calculation effciency.Using field data from Fuchunjiang Reservoir,we calculated the sensitivity of ecological parameters included in this model and validated the model.The results of sensitivity analysis showed that the parameters strongly inffuenced the phytoplankton biomass,including phytoplankton maximum growth rate,respiration rate,non-predatory mortality rate,settling rate,zooplankton maximum filtration rate,specific extinction coeffcient for suspended solids and sediment oxygen demand rate.The model was calibrated by adjusting these parameters.Total chlorophyll a(chl-a) concentrations at different layers in the water column were reproduced very well by the model simulations.The simulated chl-a values were positively correlated to the measured values with Pearson correlation coeffcient of 0.92.The mean difference between measured and simulated chl-a concentrations was 12% of the measured chl-a concentration.Measured and simulated DO concentrations were also positively correlated(r = 0.74) and the mean difference was 4% of measured DO concentrations.The successful validation of model indicated that it would be very useful in water quality management and algal bloom prediction in Fuchunjiang Reservoir and a good tool for water quality regulation of other river-style reservoirs.WU Tingfeng LUOLiancong QIN Boqiang CUI Guangbai YUZuoming YAO Zhiming 2009Journal of Environmental Sciences2009,21,3:6
20Extraction and characterization of bound extracellular polymeric substances from cultured pure cyanobacterium(Microcystis wesenbergii)显示文摘Preliminary characterization of bound extracellular polymeric substances(bEPS) of cyanobacteria is crucial to obtain a better understanding of the formation mechanism of cyanobacterial bloom. However,the characterization of bEPS can be affected by extraction methods. Five sets(including the control) of bEPS from Microcystis extracted by different methods were characterized using three-dimensional excitation and emission matrix(3DEEM) fluorescence spectroscopy combined chemical spectrophotometry; and the characterization results of bEPS samples were further compared. The agents used for extraction were NaOH,pure water and phosphate buffered saline(PBS) containing cationic exchange resins,and hot water. Extraction methods affected the fluorescence signals and intensities in the bEPS. Five fluorescence peaks were observed in the excitation and emission matrix fluorescence spectra of bEPS samples. Two peaks(peaks T1 and T2) present in all extractions were identified as protein-like fluorophores,two(peaks A and C) as humic-like fluorophores,and one(peak E) as a fulvic-like substance.Among these substances,the humic-like and fulvic-like fluorescences were only seen in the bEPS extracted with hot water. Also,NaOH solution extraction could result in strong fluorescence intensities compared to the other extraction methods. It was suggested that NaOH at pH 10.0 was the most appropriate method to extract bEPS from Microcystis. In addition,dialysis could affect the yields and characteristics of extracted bEPS during the determination process. These results will help us to explore the issues of cyanobacterial blooms.Lizhen Liu Boqiang Qin Yunlin Zhang Guangwei Zhu Guang Gao Qi Huang Xin Yao 2014Journal of Environmental Sciences2014,26,8:5
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