In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effective...In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators' needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers.展开更多
[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the...[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.展开更多
AIM: To assess the effects of poor nutritional and psychological status on tolerance of cancer treatment and the recovery of physical performance status in patients with gastrointestinal cancer. METHODS: An epidemiolo...AIM: To assess the effects of poor nutritional and psychological status on tolerance of cancer treatment and the recovery of physical performance status in patients with gastrointestinal cancer. METHODS: An epidemiological survey with respect to nutritional and psychological status in patients with gastrointestinal cancer was conducted among 182 operated patients in four provincial-level hospitals from December 2005 to June 2006. The food frequency survey method, state-trait anxiety inventory (STAI) and depression status inventory (DSI) were used to obtain information about the diet and psychological status in the patients. Nutritional status in the participants was reflected by serum albumin (Alb), hemoglobin (HB) and body mass index (BMI). RESULTS: Alb, protein intake and anxiety were associated with the severity of side effects of treatment. The adjusted relative risk (RR) for Alb, protein intake and anxiety was 3.30 (95% CI: 1.08, 10.10, P = 0.03), 3.25 (95% CI: 1.06, 9.90, P = 0.04) and 1.48 (95% CI: 1.29, 1.70, P < 0.0001), respectively. Moreover, calorie intake, HB and depression were associated with the recovery of physical performance status in the patients. Adjusted relative risk was 2.12 (95% CI: 1.09, 4.03, P = 0.028), 2.05 (95% CI: 1.08, 3.88, P =0.026) and 1.07 (95% CI: 1.02, 1.12, P = 0.007), respectively. CONCLUSION: Both poor nutrition status and psychological status are independent risk factors for severe side effects of cancer treatment, and have impact on the recovery of physical performance status in patients after treatment.展开更多
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat...Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.展开更多
An integrated methodology for eutrophication assessment,which integrates both water quality indicators(causative factors) and ecological response indicators(effect factors),is described.It is then applied to rank the ...An integrated methodology for eutrophication assessment,which integrates both water quality indicators(causative factors) and ecological response indicators(effect factors),is described.It is then applied to rank the eutrophication status of the years 2007 and 2008 in the southwest Bohai Sea.The assessment model identified that north Bohai Bay and west Laizhou Bay were the two areas with the most serious eutrophication problems in the southwest Bohai Sea.In addition,compared to that in the west Laizhou Bay,the eutrophication conditions in the north Bohai Bay was more serious in both years.Eutrophication problems such as harmful algal blooms(HABs) and low dissolved oxygen(DO) events in north Bohai Bay were frequent.The integrated method outmatched the currently used Chinese nutrient index method by definitely identifying areas with the most serious eutrophication problems,while the nutrient index method gave ambiguous results between the two years.Inclusion of both causative factors and effect factors,combining concentration,spatial coverage and frequency of indicators,as well as use of multi-season monitoring datasets in the methodology result in a more accurate,representative and useful assessment.展开更多
To understand the responses of a freshwater ecosystem to the impoundment of the Three Gorges Reservoir (TGR), phytoplankton was monitored in the tributaries of the TGR area. From August 2010 to July 2011, algal spec...To understand the responses of a freshwater ecosystem to the impoundment of the Three Gorges Reservoir (TGR), phytoplankton was monitored in the tributaries of the TGR area. From August 2010 to July 2011, algal species composition, abundance, chlorophyll a and other environmental parameters were investigated in the Gaolan River, which is a tributary of Xiangxi River. Thirty-one algal genera from seven phyla were identified. Results show that the lowest concentrations of total phosphorus (TP) and total nitrogen (TN) were 0.06 mg/L and 1.08 rag/L, respectively. The values of TP and TN exceeded the threshold concentration of the eutrophic state suggested for freshwater bodies. In the Gaolan River, the succession of phytoplankton showed clear seasonal characteristics. Different dominant species were observed among seasons under the control of environment factors. In spring and summer, the dominant species were Nitzschia sp. and Aphanizomenon flos-aquae (L.) Ralfs, the limiting nutrient was NO3^--N, and the key environmental factor for phytoplankton population succession was water temperature (WT). In autumn and winter, the dominant species were A.flos-aquae and Chlorella sp., the limiting nutrient was pO3--P, and the key environmental factors were transparency and WT. This study illustrates the influence of physical and chemical factors on phytoplankton seasonal succession in a tributary of TGR since the downstream regions of Xiangxi River and Gaolan River became reservoirs after impoundment of the Three Gorges Dam. We suggest that this activity has significantly affected water quality in the dam area.展开更多
The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were...The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were investigated in two reservoirs (Xiquanyan Reservoir and Taoshan Reservoir) in Northeast China in 2009. The two reservoirs showed strong seasonal fluctuations in their physical and chemical composition. Results of the trophic status index indicated that Xiaquanyan Reservoir was mesotrophic, whilst Taoshan Reservoir was eutrophic. Diatoms were the dominant phytoplankton group in Xiquanyan Reservoir throughout all seasons of the study, while in Taoshan Reservoir, diatoms dominated in spring, and cyanobacteria dominated in summer and autumn. This difference was resulted from differences in local environmental factors, including nutrients and hydrology. This study suggests that in mesotrophic reservoirs, nutrients played a key role in controlling seasonal phytoplankton successions, whereas in eutrophic reservoirs water temperature was the key factor in a cold region. Notably, the dominant species in summer in the Taoshan Reservoir was Microcystis, which may produce toxins depending on the ambient conditions, and presenting a risk of local toxin contamination.展开更多
Although biomass variations in Microcystis and microcystin have been widely reported,few studies have addressed whether different trophic states of natural lake water affect the spatial-temporal variations in abundanc...Although biomass variations in Microcystis and microcystin have been widely reported,few studies have addressed whether different trophic states of natural lake water affect the spatial-temporal variations in abundances of microcystin-producing Microcystis in a given bloom.In this study,we used a harmful algal bloom in Chaohu Lake,eastern China,as an example to investigate the mutual relationship between different nutrient states and environmental factors,and the impact on Microcystis.Overall,cyanobacteria and Microcystis were more abundant in the middle and western parts of the lake under high nutrients levels,while in the eastern part,nutrient concentrations were low enough to limit biomass,and their fluctuations affected the contents of toxic Microcystis.Moreover,microcystin concentration was correlated positively to nutrient levels and Microcystis biomass during bloom developing in 2013 from June to August.Temporally,the cellular content of total microcystin was lowest when the bloom peaked in intensity.Our results suggest that lake eutrophication not only results in cyanobacterial blooms,but may also increase the proportion of toxic Microcystis species and their cell-bound MCs contents(i.e.microcystin cell quotas) under mild eutrophication.The present investigation provided molecular evidence for the selection of MC-producing and non-MC-producing genotypes.The current study provides new evidence advocating the monitoring of partitions of large lakes when studying cyanobacteria and toxin-contaminated freshwaters,which will be beneficial for both water agencies and water researchers.展开更多
We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic s...We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic status and rotifer community structure. Twenty-nine rotifer species were collected, of which Keratella cochlearis, Polyarthra dolichoptera, and Trichocerca elongate were dominant. The mean density, Shannon-Wiener diversity, and equitability among the five lakes differed significantly (P〈0.05). The mean rotifer density was positively correlated with trophic state. The diversity was higher in lakes with high macrophyte coverage. The composition of rotifer species was closely associated with the trophic gradient. Five environmental variables, Secchi depth, conductivity, TN, NHa-N, and TP, significantly affected the composition of rotifer species. Keratella quadrata, Brachionus calyciflorus, and B. forficula were more common in eutrophic conditions. Our results suggest that eutrophication has a significant influence on the rotifer community structure and highlight the potential for using rotifer community structure as an indicator of trophic status in subtropical lakes.展开更多
To realize potential cost savings in coastal monitoring programs and provide timely advice for marine management, there is an urgent need for efficient evaluation tools based on easily measured variables for the rapid...To realize potential cost savings in coastal monitoring programs and provide timely advice for marine management, there is an urgent need for efficient evaluation tools based on easily measured variables for the rapid and timely assessment of estuarine and offshore eutrophication. In this study, using parallel factor analysis(PARAFAC), principal component analysis(PCA), and discriminant function analysis(DFA) with the trophic index(TRIX) for reference, we developed an approach for rapidly assessing the eutrophication status of coastal waters using easy-to-measure parameters, including chromophoric dissolved organic matter(CDOM), fluorescence excitation–emission matrices, CDOM UV-Vis absorbance, and other water-quality parameters(turbidity, chlorophyll a, and dissolved oxygen). First, we decomposed CDOM excitation-emission matrices(EEMs) by PARAFAC to identify three components. Then, we applied PCA to simplify the complexity of the relationships between the water-quality parameters. Finally, we used the PCA score values as independent variables in DFA to develop a eutrophication assessment model. The developed model yielded classification accuracy rates of 97.1%, 80.5%, 90.3%, and 89.1% for good, moderate, and poor water qualities, and for the overall data sets, respectively. Our results suggest that these easy-to-measure parameters could be used to develop a simple approach for rapid in-situ assessment and monitoring of the eutrophication of estuarine and offshore areas.展开更多
Postgastrectomy syndromes evoked by the loss of several gastric functions after total or subtotal gastrectomy are very common. Dif- ferent kinds of reconstruction have been developed to overcome the problem. Patients ...Postgastrectomy syndromes evoked by the loss of several gastric functions after total or subtotal gastrectomy are very common. Dif- ferent kinds of reconstruction have been developed to overcome the problem. Patients with preservation of a duodenal passage and jejunal interposition with or without a pouch show a better quality of life and mini- mal symptoms postoperatively. A jejunal interposition with or without a pouch after proximal or distal subtotal gastrictomy seems to improve the nutritional condition and quality of life. The prognostic nutritional index (PNI), Visick score, Spitzer index and the European Organization for Re- search and Treatment of Cancer (EORTC) questionnaire (QLQ-C30) are available to evaluate the quality of life and nutritional status after gastrec- tomy.展开更多
[Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir.[Method] Chlorophyll-a and water quality factors of water quality of Wetl...[Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir.[Method] Chlorophyll-a and water quality factors of water quality of Wetlands BaiGuishan Reservoir was studied,the analysis of the relationship on water quality of Wetlands Baiguishan Reservoir was made by use of trophic status indices and SPSS17.0 statistical analysis.[Result] Total phosphorus was an important factor of influence Chlorophyll-a in reservoir,water body had slight eutrophication phenomenon in reservoir of July to October in 2010.[Conclusion] Comprehensive management should be strengthened so as to improve the water quality of Baiguishan wetland.展开更多
The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake i...The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake is of great importance to the improvement of water environment in the valley and the eutrophication status in th lake. Firstly, the basic ideas, key taches and main methods for water pollution control of inflow rivers of Taihu Lake was put forward in this article, Basic on these theories, the pollutant source status in the comprehensive treatment zone of the 15 major inflow rivers was analysized, the countermeasures of pollution control and main regulation projects were introduced, and the total abatement of pollutants was predicted. With the implement of regulation projects, the number of rivers with water quality worse than Grade V among the 15 major inflow rivers had come from 9 to 3, and the eutrophication status of Taihu Lake had changed from medium level to light level. The overall treatment of the major inflow rivers of the Taihu Lake had achieved initial success.展开更多
To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by pri...To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by principal component analysis, stepwise discriminant analysis, and t-tests. Although they clearly differed morphologically, plots of the principal components of the two strains partially overlapped. However, the difference between the strains was supported with very high precision by discriminant analysis. The t-tests revealed that 4 of the 13 morphological traits analyzed were highly significantly different (P<0.01), 4 traits also differed significantly (P<0.05), and the remainder did not differ significantly. The coefficients of difference of the 13 traits were all lower than the threshold value between subspecies (1.28). Together, the results indicate that a trend for segregation of characters from the common cultured strain have already appeared in the selected fast-growing strain but the degree of segregation have not risen to subspecies level.展开更多
We made comparative studies of three tropical ox-bow lakes in India with different trophic states.The species number of zooplanktons was negatively correlated with the degree of water eutrophication,and lakes of simil...We made comparative studies of three tropical ox-bow lakes in India with different trophic states.The species number of zooplanktons was negatively correlated with the degree of water eutrophication,and lakes of similar trophic status had higher similarity of species.The most significant differences of species composition were observed with rotifers and zoobenthos.The density and biomass of phytoplankton,rotifers,oligochaetes and chironomids tended to increase with increasing nutrients.We observed a significant difference of dominant species in different waters,especially the eutrophic lake,which was dominated by a few species of oligochaetes.The abundance of Tanypus bilobatus showed a highly significant correlation with the degree of eutrophication.Rotifers and zoobenthos showed considerably lower biodiversity in the eutrophic lake.展开更多
Population growth has consequences for intense use of aquatic ecosystems. Samples were taken, between 2013 and 2014, in the reservoirs "Algodoeiro" and "Gloria" in Sergipe, Brazil. TSI (Trophic State Index) and ...Population growth has consequences for intense use of aquatic ecosystems. Samples were taken, between 2013 and 2014, in the reservoirs "Algodoeiro" and "Gloria" in Sergipe, Brazil. TSI (Trophic State Index) and WQI (Water Quality Index) were used. It was determined the parameters such as conductivity, dissolved oxygen, total nitrogen, total phosphorus and chlorophyll. TSI has been applied, in "Algodoeiro", which was classified as mesotrophic. With the increase of rainfall in 2014, this reservoir changed its condition to eutrophic. "Gloria" reservoir was already classified in super-eutrophication. Regarding the WQI, the reservoirs were classified in Class IV, indicating a critically degraded condition.展开更多
Trophic status of some freshwater lakes all over the world, including Russia, Byelorussia, Japan, Sweden and China, has been assessed. The research submitted is based on the approach developed by OECD (Organization E...Trophic status of some freshwater lakes all over the world, including Russia, Byelorussia, Japan, Sweden and China, has been assessed. The research submitted is based on the approach developed by OECD (Organization Economic Cooperation and Development). Annual total phosphorus averages formed a classification system. A probability assumption for each water body to reach some given trophic status was taken into account. Probability distribution curves for the average lake phosphorus have been analytically approximated.展开更多
基金The US National Science Foundation(No.CM M I-0408390,CM M I-0644552)the National Natural Science Foundation of China(No.U1134206,51250110075,51150110478)+1 种基金the Western Project of M inistry of Communications of China(No.0901005C)the Natural Science Foundation of Jiangsu Province(No.BK200910046)
文摘In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators' needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers.
文摘[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.
基金Supported by Foundation of Fujian Medical University, No.Js060017
文摘AIM: To assess the effects of poor nutritional and psychological status on tolerance of cancer treatment and the recovery of physical performance status in patients with gastrointestinal cancer. METHODS: An epidemiological survey with respect to nutritional and psychological status in patients with gastrointestinal cancer was conducted among 182 operated patients in four provincial-level hospitals from December 2005 to June 2006. The food frequency survey method, state-trait anxiety inventory (STAI) and depression status inventory (DSI) were used to obtain information about the diet and psychological status in the patients. Nutritional status in the participants was reflected by serum albumin (Alb), hemoglobin (HB) and body mass index (BMI). RESULTS: Alb, protein intake and anxiety were associated with the severity of side effects of treatment. The adjusted relative risk (RR) for Alb, protein intake and anxiety was 3.30 (95% CI: 1.08, 10.10, P = 0.03), 3.25 (95% CI: 1.06, 9.90, P = 0.04) and 1.48 (95% CI: 1.29, 1.70, P < 0.0001), respectively. Moreover, calorie intake, HB and depression were associated with the recovery of physical performance status in the patients. Adjusted relative risk was 2.12 (95% CI: 1.09, 4.03, P = 0.028), 2.05 (95% CI: 1.08, 3.88, P =0.026) and 1.07 (95% CI: 1.02, 1.12, P = 0.007), respectively. CONCLUSION: Both poor nutrition status and psychological status are independent risk factors for severe side effects of cancer treatment, and have impact on the recovery of physical performance status in patients after treatment.
基金Supported by the Natural Science Foundation of Guangxi Province,China(Nos.2012GXNSFEA053001,2010GXNSFE013001,2011GXNSFE018002,2011GXNSFA018108)
文摘Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.
基金Supported by the National Basic Research Program of China(973 Program)(No.2010CB428706)the Ocean Public Welfare Scientific Research Project,State Oceanic Administration of China(No.201205001)the Special Funds Supporting Project for Construction of"Blue Economic Zone"in Shandong Peninsula of China,and the Fund for Creative Research Groups by NSFC(No.41121064)
文摘An integrated methodology for eutrophication assessment,which integrates both water quality indicators(causative factors) and ecological response indicators(effect factors),is described.It is then applied to rank the eutrophication status of the years 2007 and 2008 in the southwest Bohai Sea.The assessment model identified that north Bohai Bay and west Laizhou Bay were the two areas with the most serious eutrophication problems in the southwest Bohai Sea.In addition,compared to that in the west Laizhou Bay,the eutrophication conditions in the north Bohai Bay was more serious in both years.Eutrophication problems such as harmful algal blooms(HABs) and low dissolved oxygen(DO) events in north Bohai Bay were frequent.The integrated method outmatched the currently used Chinese nutrient index method by definitely identifying areas with the most serious eutrophication problems,while the nutrient index method gave ambiguous results between the two years.Inclusion of both causative factors and effect factors,combining concentration,spatial coverage and frequency of indicators,as well as use of multi-season monitoring datasets in the methodology result in a more accurate,representative and useful assessment.
基金Supported by the National Major Programs of Water Body Pollution Control and Remediation(No.2012ZX07103003-02)the National Basic Research Program of China(973 Program)(No.2008CB418000)
文摘To understand the responses of a freshwater ecosystem to the impoundment of the Three Gorges Reservoir (TGR), phytoplankton was monitored in the tributaries of the TGR area. From August 2010 to July 2011, algal species composition, abundance, chlorophyll a and other environmental parameters were investigated in the Gaolan River, which is a tributary of Xiangxi River. Thirty-one algal genera from seven phyla were identified. Results show that the lowest concentrations of total phosphorus (TP) and total nitrogen (TN) were 0.06 mg/L and 1.08 rag/L, respectively. The values of TP and TN exceeded the threshold concentration of the eutrophic state suggested for freshwater bodies. In the Gaolan River, the succession of phytoplankton showed clear seasonal characteristics. Different dominant species were observed among seasons under the control of environment factors. In spring and summer, the dominant species were Nitzschia sp. and Aphanizomenon flos-aquae (L.) Ralfs, the limiting nutrient was NO3^--N, and the key environmental factor for phytoplankton population succession was water temperature (WT). In autumn and winter, the dominant species were A.flos-aquae and Chlorella sp., the limiting nutrient was pO3--P, and the key environmental factors were transparency and WT. This study illustrates the influence of physical and chemical factors on phytoplankton seasonal succession in a tributary of TGR since the downstream regions of Xiangxi River and Gaolan River became reservoirs after impoundment of the Three Gorges Dam. We suggest that this activity has significantly affected water quality in the dam area.
基金Supported by the Fundamental Research Funds for the Central Universities(No.DL11BA20)the GRAP09-Excellent Doctor Paper of Northeast Forestry Universitythe Science and Technology Project of Heilongjiang Province(No.GBQ9C103)
文摘The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were investigated in two reservoirs (Xiquanyan Reservoir and Taoshan Reservoir) in Northeast China in 2009. The two reservoirs showed strong seasonal fluctuations in their physical and chemical composition. Results of the trophic status index indicated that Xiaquanyan Reservoir was mesotrophic, whilst Taoshan Reservoir was eutrophic. Diatoms were the dominant phytoplankton group in Xiquanyan Reservoir throughout all seasons of the study, while in Taoshan Reservoir, diatoms dominated in spring, and cyanobacteria dominated in summer and autumn. This difference was resulted from differences in local environmental factors, including nutrients and hydrology. This study suggests that in mesotrophic reservoirs, nutrients played a key role in controlling seasonal phytoplankton successions, whereas in eutrophic reservoirs water temperature was the key factor in a cold region. Notably, the dominant species in summer in the Taoshan Reservoir was Microcystis, which may produce toxins depending on the ambient conditions, and presenting a risk of local toxin contamination.
基金Supported by the Major Science and Technology Program for Water Pollution Control and Treatment(Nos.2012ZX07103-004-02,2015ZX07204002)the Henan Institute of Engineering Innovation Team Building Program(No.CXTD2014005)+2 种基金the Henan Province Science Projects for Colleges and Universities(No.15A610011)the City Science and Technology Project(No.20140659)the Fund Project for Doctor(No.D2014009)
文摘Although biomass variations in Microcystis and microcystin have been widely reported,few studies have addressed whether different trophic states of natural lake water affect the spatial-temporal variations in abundances of microcystin-producing Microcystis in a given bloom.In this study,we used a harmful algal bloom in Chaohu Lake,eastern China,as an example to investigate the mutual relationship between different nutrient states and environmental factors,and the impact on Microcystis.Overall,cyanobacteria and Microcystis were more abundant in the middle and western parts of the lake under high nutrients levels,while in the eastern part,nutrient concentrations were low enough to limit biomass,and their fluctuations affected the contents of toxic Microcystis.Moreover,microcystin concentration was correlated positively to nutrient levels and Microcystis biomass during bloom developing in 2013 from June to August.Temporally,the cellular content of total microcystin was lowest when the bloom peaked in intensity.Our results suggest that lake eutrophication not only results in cyanobacterial blooms,but may also increase the proportion of toxic Microcystis species and their cell-bound MCs contents(i.e.microcystin cell quotas) under mild eutrophication.The present investigation provided molecular evidence for the selection of MC-producing and non-MC-producing genotypes.The current study provides new evidence advocating the monitoring of partitions of large lakes when studying cyanobacteria and toxin-contaminated freshwaters,which will be beneficial for both water agencies and water researchers.
基金Supported by the Special Fund for Agro-Scientific Research in the Public Interest(No.20130356)the National Key Technology Research and Development Program of China(No.2012BAD25B08)the National Natural Science Foundation of China(Nos.30830025,31201994)
文摘We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic status and rotifer community structure. Twenty-nine rotifer species were collected, of which Keratella cochlearis, Polyarthra dolichoptera, and Trichocerca elongate were dominant. The mean density, Shannon-Wiener diversity, and equitability among the five lakes differed significantly (P〈0.05). The mean rotifer density was positively correlated with trophic state. The diversity was higher in lakes with high macrophyte coverage. The composition of rotifer species was closely associated with the trophic gradient. Five environmental variables, Secchi depth, conductivity, TN, NHa-N, and TP, significantly affected the composition of rotifer species. Keratella quadrata, Brachionus calyciflorus, and B. forficula were more common in eutrophic conditions. Our results suggest that eutrophication has a significant influence on the rotifer community structure and highlight the potential for using rotifer community structure as an indicator of trophic status in subtropical lakes.
基金the National Natural Science Foundation of China (No. 41376106)the Shandong Provincial Natural Science Foundation of China (No. ZR2013DM017)
文摘To realize potential cost savings in coastal monitoring programs and provide timely advice for marine management, there is an urgent need for efficient evaluation tools based on easily measured variables for the rapid and timely assessment of estuarine and offshore eutrophication. In this study, using parallel factor analysis(PARAFAC), principal component analysis(PCA), and discriminant function analysis(DFA) with the trophic index(TRIX) for reference, we developed an approach for rapidly assessing the eutrophication status of coastal waters using easy-to-measure parameters, including chromophoric dissolved organic matter(CDOM), fluorescence excitation–emission matrices, CDOM UV-Vis absorbance, and other water-quality parameters(turbidity, chlorophyll a, and dissolved oxygen). First, we decomposed CDOM excitation-emission matrices(EEMs) by PARAFAC to identify three components. Then, we applied PCA to simplify the complexity of the relationships between the water-quality parameters. Finally, we used the PCA score values as independent variables in DFA to develop a eutrophication assessment model. The developed model yielded classification accuracy rates of 97.1%, 80.5%, 90.3%, and 89.1% for good, moderate, and poor water qualities, and for the overall data sets, respectively. Our results suggest that these easy-to-measure parameters could be used to develop a simple approach for rapid in-situ assessment and monitoring of the eutrophication of estuarine and offshore areas.
文摘Postgastrectomy syndromes evoked by the loss of several gastric functions after total or subtotal gastrectomy are very common. Dif- ferent kinds of reconstruction have been developed to overcome the problem. Patients with preservation of a duodenal passage and jejunal interposition with or without a pouch show a better quality of life and mini- mal symptoms postoperatively. A jejunal interposition with or without a pouch after proximal or distal subtotal gastrictomy seems to improve the nutritional condition and quality of life. The prognostic nutritional index (PNI), Visick score, Spitzer index and the European Organization for Re- search and Treatment of Cancer (EORTC) questionnaire (QLQ-C30) are available to evaluate the quality of life and nutritional status after gastrec- tomy.
基金Supported by Natural Science Study Fund from the Department of Education of Henan(2010B610002)
文摘[Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir.[Method] Chlorophyll-a and water quality factors of water quality of Wetlands BaiGuishan Reservoir was studied,the analysis of the relationship on water quality of Wetlands Baiguishan Reservoir was made by use of trophic status indices and SPSS17.0 statistical analysis.[Result] Total phosphorus was an important factor of influence Chlorophyll-a in reservoir,water body had slight eutrophication phenomenon in reservoir of July to October in 2010.[Conclusion] Comprehensive management should be strengthened so as to improve the water quality of Baiguishan wetland.
文摘The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake is of great importance to the improvement of water environment in the valley and the eutrophication status in th lake. Firstly, the basic ideas, key taches and main methods for water pollution control of inflow rivers of Taihu Lake was put forward in this article, Basic on these theories, the pollutant source status in the comprehensive treatment zone of the 15 major inflow rivers was analysized, the countermeasures of pollution control and main regulation projects were introduced, and the total abatement of pollutants was predicted. With the implement of regulation projects, the number of rivers with water quality worse than Grade V among the 15 major inflow rivers had come from 9 to 3, and the eutrophication status of Taihu Lake had changed from medium level to light level. The overall treatment of the major inflow rivers of the Taihu Lake had achieved initial success.
基金Supported by the Fund for Modern Agro-Industry Technology Research System (No. CARS-50)the National Key Technology R&D Program of China(No. 2006BAD01A12012)the National High Technology Research and Development Program of China (863 Program) (No. 2012AA10A408-8)
文摘To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by principal component analysis, stepwise discriminant analysis, and t-tests. Although they clearly differed morphologically, plots of the principal components of the two strains partially overlapped. However, the difference between the strains was supported with very high precision by discriminant analysis. The t-tests revealed that 4 of the 13 morphological traits analyzed were highly significantly different (P<0.01), 4 traits also differed significantly (P<0.05), and the remainder did not differ significantly. The coefficients of difference of the 13 traits were all lower than the threshold value between subspecies (1.28). Together, the results indicate that a trend for segregation of characters from the common cultured strain have already appeared in the selected fast-growing strain but the degree of segregation have not risen to subspecies level.
文摘We made comparative studies of three tropical ox-bow lakes in India with different trophic states.The species number of zooplanktons was negatively correlated with the degree of water eutrophication,and lakes of similar trophic status had higher similarity of species.The most significant differences of species composition were observed with rotifers and zoobenthos.The density and biomass of phytoplankton,rotifers,oligochaetes and chironomids tended to increase with increasing nutrients.We observed a significant difference of dominant species in different waters,especially the eutrophic lake,which was dominated by a few species of oligochaetes.The abundance of Tanypus bilobatus showed a highly significant correlation with the degree of eutrophication.Rotifers and zoobenthos showed considerably lower biodiversity in the eutrophic lake.
文摘Population growth has consequences for intense use of aquatic ecosystems. Samples were taken, between 2013 and 2014, in the reservoirs "Algodoeiro" and "Gloria" in Sergipe, Brazil. TSI (Trophic State Index) and WQI (Water Quality Index) were used. It was determined the parameters such as conductivity, dissolved oxygen, total nitrogen, total phosphorus and chlorophyll. TSI has been applied, in "Algodoeiro", which was classified as mesotrophic. With the increase of rainfall in 2014, this reservoir changed its condition to eutrophic. "Gloria" reservoir was already classified in super-eutrophication. Regarding the WQI, the reservoirs were classified in Class IV, indicating a critically degraded condition.
文摘Trophic status of some freshwater lakes all over the world, including Russia, Byelorussia, Japan, Sweden and China, has been assessed. The research submitted is based on the approach developed by OECD (Organization Economic Cooperation and Development). Annual total phosphorus averages formed a classification system. A probability assumption for each water body to reach some given trophic status was taken into account. Probability distribution curves for the average lake phosphorus have been analytically approximated.