The internal response of shallow lakes to external factors is very important to investigate for understanding their role in long-term changes of the shallow lake ecosystem. The current study investigated the impacts of long-term wind dynamics on in-lake processes of the degraded shallow lake. The long-term high-frequency wind field, water quality, and Chlorophyll-a data analysis showed that there were two groups of variables found with higher internal similarity at Meiliang bay of large, shallow Lake Taihu. The temporal trends of wind, temperature, and Chl-a found highly consistent while dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), suspended solids (SS) and Secchi depth were not significantly correlated in long-term temporal trends analysis. The results showed that Chl-a and other shallow lake ecosystem variables (abiotic) are strongly related to long-term wind field. The changes in nutrients and lower mixing scenarios trigger the growth of Chl-a and onshore lower winds help in the formation of colonies. There was a shift in wind and internal response variables before and after 2006. Wind and internal water quality parameters were highly variable before 2006 whereas, decline in wind speeds along with stable wind directional switching caused intense blooms formation along with thermal stratification (warming) for a longer period of time (after 2006) in the shoreline areas. The current study can help to understand the internal ecosystem response mechanisms in long-term interactions with wind field to control the eutrophication and algal blooms.
{"title":"Long-term wind induced internal response mechanisms at Meiliang Bay of large, shallow Lake Taihu","authors":"A. Jalil, Ke Zhang, L. Qi, Yiping Li","doi":"10.1051/limn/2019026","DOIUrl":"https://doi.org/10.1051/limn/2019026","url":null,"abstract":"The internal response of shallow lakes to external factors is very important to investigate for understanding their role in long-term changes of the shallow lake ecosystem. The current study investigated the impacts of long-term wind dynamics on in-lake processes of the degraded shallow lake. The long-term high-frequency wind field, water quality, and Chlorophyll-a data analysis showed that there were two groups of variables found with higher internal similarity at Meiliang bay of large, shallow Lake Taihu. The temporal trends of wind, temperature, and Chl-a found highly consistent while dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), suspended solids (SS) and Secchi depth were not significantly correlated in long-term temporal trends analysis. The results showed that Chl-a and other shallow lake ecosystem variables (abiotic) are strongly related to long-term wind field. The changes in nutrients and lower mixing scenarios trigger the growth of Chl-a and onshore lower winds help in the formation of colonies. There was a shift in wind and internal response variables before and after 2006. Wind and internal water quality parameters were highly variable before 2006 whereas, decline in wind speeds along with stable wind directional switching caused intense blooms formation along with thermal stratification (warming) for a longer period of time (after 2006) in the shoreline areas. The current study can help to understand the internal ecosystem response mechanisms in long-term interactions with wind field to control the eutrophication and algal blooms.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"42 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77477415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
On the surface of Microcystis cells, there is a carbohydrate called extracellular polysaccharides (EPS) playing a significant role in the colony formation of Microcystis. EPS consists of tightly cell-bound EPS (TB-EPS), and both of these substances are considered to be strongly related to the colony formation and buoyancy of Microcystis. In this study, Microcystis aeruginosa (strain: NIES-843) was used to examine the effects of EPS, TB-EPS, and divalent metal cations such as calcium and magnesium on the buoyancy and colony formation of M. aeruginosa NIES-843. Under various light conditions, the addition of TB-EPS into the culture medium induced M. aeruginosa NIES-843 to obtain high buoyancy at concentrations of Ca2+ and Mg2+ concentrations of 10 mg/L and 30 mg/L, respectively. Under the absence of light, the addition of EPS could lead M. aeruginosa to form a colony and obtain buoyancy, and the addition of TB-EPS could not significantly change the buoyancy of M. aeruginosa NIES-843. The colony size analysis showed that at the same cationic concentration, the addition of TB-EPS could induce M. aeruginosa to form the largest colony and present strong buoyancy. This study suggested that temperature and illumination are conducive to colony formation and present higher buoyancy of M. aeruginosa.
{"title":"Impacts of different extracellular polysaccharides on colony formation and buoyancy of Microcystis aeruginosa","authors":"Kai Wei, Y. Amano, M. Machida","doi":"10.1051/limn/2020026","DOIUrl":"https://doi.org/10.1051/limn/2020026","url":null,"abstract":"On the surface of Microcystis cells, there is a carbohydrate called extracellular polysaccharides (EPS) playing a significant role in the colony formation of Microcystis. EPS consists of tightly cell-bound EPS (TB-EPS), and both of these substances are considered to be strongly related to the colony formation and buoyancy of Microcystis. In this study, Microcystis aeruginosa (strain: NIES-843) was used to examine the effects of EPS, TB-EPS, and divalent metal cations such as calcium and magnesium on the buoyancy and colony formation of M. aeruginosa NIES-843. Under various light conditions, the addition of TB-EPS into the culture medium induced M. aeruginosa NIES-843 to obtain high buoyancy at concentrations of Ca2+ and Mg2+ concentrations of 10 mg/L and 30 mg/L, respectively. Under the absence of light, the addition of EPS could lead M. aeruginosa to form a colony and obtain buoyancy, and the addition of TB-EPS could not significantly change the buoyancy of M. aeruginosa NIES-843. The colony size analysis showed that at the same cationic concentration, the addition of TB-EPS could induce M. aeruginosa to form the largest colony and present strong buoyancy. This study suggested that temperature and illumination are conducive to colony formation and present higher buoyancy of M. aeruginosa.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"83 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75893289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Freshwater bivalves in shallow waters are often exposed to extended periods of drought and are highly affected due to their limited mobility. Their adaptation to emersion is a key factor for survival, particularly during human-made unnatural water regime fluctuations or short-term droughts. In the current study, survival durations of two freshwater bivalve species (Unio terminalis, Unionidae and Corbicula fluminea, Cyrenidae) were tested under two experimental emersion conditions (presence of water-saturated sediment and without sediment). U. terminalis' mean survival duration more than doubled in the water-saturated sediment treatment (992 h) compared to treatment without sediment (448 h). For C. fluminea, the mean survival duration in the water-saturated sediment treatment (278 h) was over 50% longer than that recorded in the treatment without sediment (174 h). Both species probably made behavioral adjustments according to the environmental conditions to respond to the presence of the water-saturated sediment and maximized their survival chances. In general, U. terminalis survived significantly longer than C. fluminea in both treatments. No effects of size on survival were observed for either species.
{"title":"Survival durations and behavioural adjustments of two freshwater bivalves (Unio terminalis, Unionida and Corbicula fluminea, Venerida) under two emersion conditions","authors":"M. Güler","doi":"10.1051/limn/2020027","DOIUrl":"https://doi.org/10.1051/limn/2020027","url":null,"abstract":"Freshwater bivalves in shallow waters are often exposed to extended periods of drought and are highly affected due to their limited mobility. Their adaptation to emersion is a key factor for survival, particularly during human-made unnatural water regime fluctuations or short-term droughts. In the current study, survival durations of two freshwater bivalve species (Unio terminalis, Unionidae and Corbicula fluminea, Cyrenidae) were tested under two experimental emersion conditions (presence of water-saturated sediment and without sediment). U. terminalis' mean survival duration more than doubled in the water-saturated sediment treatment (992 h) compared to treatment without sediment (448 h). For C. fluminea, the mean survival duration in the water-saturated sediment treatment (278 h) was over 50% longer than that recorded in the treatment without sediment (174 h). Both species probably made behavioral adjustments according to the environmental conditions to respond to the presence of the water-saturated sediment and maximized their survival chances. In general, U. terminalis survived significantly longer than C. fluminea in both treatments. No effects of size on survival were observed for either species.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"75 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75000574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Toxic stress caused by pesticides changes the function and structure of the aquatic ecosystem via impressing to species composition. Therefore it is necessary to determine the reaction of cyanobacteria to pesticides for comprehend the effects of these substances on the aquatic ecosystems. This study aims to determine the toxicity and oxidative stress that Lambda cyhalothrin may cause in cyanobacteria, one of the primary producers in lake ecosystems. For these reasons, the changes in chlorophyll-acontent, OD560 absorbance, the antioxidant enzyme acitvities such as superoxidedismutase (SOD), ascorbate peroxidase (APX), and glutathione reducatse (GR) were assessed to carry out the effect of Lambda cyhalothrin concentrations (between 6.25 and 100 μg ml−1) onArthrospira platensis. EC50 value is calculated as 11.94 μg m l−1Lambda cyhalothrin concentrations. SOD and APX activities was statistically different from the control at 100 μg m l−1Lambda cyhalothrin application compared to control inA. platensis-M2 cells. On the other hand, GR activity did not effect significantly. According to our results, we may conclude that Lambda cyhalothrin concentrations used in this study inhibited the growth ofA. platensiscells in a time and dose-dependent manner, as indicated by lowered chlorophyll-acontent and OD560 values and Lambda cyhalothrin caused oxidative stress inA. platensiscells. As a result, the restriction of Lambda cyhalothrin using at the certain concentrations may be a step to prevent pesticide pollution in the environment.
{"title":"Determination of changes inArthrospira platensisantioxidant activity and growth parameters due to oxidative stress arising from Lambda cyhalothrin","authors":"H. Tunca","doi":"10.1051/limn/2020024","DOIUrl":"https://doi.org/10.1051/limn/2020024","url":null,"abstract":"Toxic stress caused by pesticides changes the function and structure of the aquatic ecosystem via impressing to species composition. Therefore it is necessary to determine the reaction of cyanobacteria to pesticides for comprehend the effects of these substances on the aquatic ecosystems. This study aims to determine the toxicity and oxidative stress that Lambda cyhalothrin may cause in cyanobacteria, one of the primary producers in lake ecosystems. For these reasons, the changes in chlorophyll-acontent, OD560 absorbance, the antioxidant enzyme acitvities such as superoxidedismutase (SOD), ascorbate peroxidase (APX), and glutathione reducatse (GR) were assessed to carry out the effect of Lambda cyhalothrin concentrations (between 6.25 and 100 μg ml−1) onArthrospira platensis. EC50 value is calculated as 11.94 μg m l−1Lambda cyhalothrin concentrations. SOD and APX activities was statistically different from the control at 100 μg m l−1Lambda cyhalothrin application compared to control inA. platensis-M2 cells. On the other hand, GR activity did not effect significantly. According to our results, we may conclude that Lambda cyhalothrin concentrations used in this study inhibited the growth ofA. platensiscells in a time and dose-dependent manner, as indicated by lowered chlorophyll-acontent and OD560 values and Lambda cyhalothrin caused oxidative stress inA. platensiscells. As a result, the restriction of Lambda cyhalothrin using at the certain concentrations may be a step to prevent pesticide pollution in the environment.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"9 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81322955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Understanding temporal dynamics of community may provide insights on biological responses under environmental changes. However, our knowledge on temporal dynamics of river organisms is still limited. In the present study, we employed a multivariate time-series modeling approach with a long-term dataset (i.e. 72 consecutive months) to investigate temporal dynamics of benthic diatom communities in four sites located in a Chinese mountainous river network. We hypothesized that: (1) there are multi-scale temporal dynamics within the diatom community; (2) intra-annual fluctuations dominate the community dynamics; (3) diatom species composing the community respond distinctly to environmental changes. We found that intra-annual fluctuations with periodicities <12 months explained 8.1–16.1% of community variation. In contrast, fluctuations with periodicities of 13–36 months and 37–72 months only accounted for 1.1–5.9% and 2.8–9.7% of variance in diatom community dynamics, respectively. Taxa correlating significantly to each significant RDA axis (namely, RDA taxa group) displayed distinct temporal dynamics. Conductivity, total nitrogen, and pH were important to most RDA taxa groups across the four sites while their effects were group-specific. We concluded that intra-annual dynamics dominated temporal variation in diatom communities due to community responses to local environmental fluctuations. We suggest that long-term monitoring data are valuable for identifying multiple-scale temporal dynamics within biological communities.
{"title":"Intra-annual fluctuations dominating temporal dynamics of benthic diatom assemblages in a Chinese mountainous river","authors":"Shuhan Guo, Fengzhi He, T. Tang, Lu Tan, Q. Cai","doi":"10.1051/limn/2020020","DOIUrl":"https://doi.org/10.1051/limn/2020020","url":null,"abstract":"Understanding temporal dynamics of community may provide insights on biological responses under environmental changes. However, our knowledge on temporal dynamics of river organisms is still limited. In the present study, we employed a multivariate time-series modeling approach with a long-term dataset (i.e. 72 consecutive months) to investigate temporal dynamics of benthic diatom communities in four sites located in a Chinese mountainous river network. We hypothesized that: (1) there are multi-scale temporal dynamics within the diatom community; (2) intra-annual fluctuations dominate the community dynamics; (3) diatom species composing the community respond distinctly to environmental changes. We found that intra-annual fluctuations with periodicities <12 months explained 8.1–16.1% of community variation. In contrast, fluctuations with periodicities of 13–36 months and 37–72 months only accounted for 1.1–5.9% and 2.8–9.7% of variance in diatom community dynamics, respectively. Taxa correlating significantly to each significant RDA axis (namely, RDA taxa group) displayed distinct temporal dynamics. Conductivity, total nitrogen, and pH were important to most RDA taxa groups across the four sites while their effects were group-specific. We concluded that intra-annual dynamics dominated temporal variation in diatom communities due to community responses to local environmental fluctuations. We suggest that long-term monitoring data are valuable for identifying multiple-scale temporal dynamics within biological communities.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"1 1","pages":"22"},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89679395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maiara Tábatha da Silva Brito, L. P. Diniz, U. M. Pozzobom, V. Landeiro, F. Sousa
Studies on Cladocera biodiversity in Brazilian freshwater ecosystems are intensifying. However, the fauna of some hydrographic regions is still poorly known. We investigated the richness and species composition of cladocerans in lakes of the Pantanal from the state of Mato Grosso (Paraguay hydrographic region), Brazil. In addition, we cataloged the known cladoceran species in each hydrographic region of the state. Occurrence data were obtained from the literature and samples collected from 50 lakes in the northern Pantanal. We recorded 120 cladoceran species from eight families in the state of Mato Grosso. The occurrence of these species was recorded in the Amazon and Paraguay hydrographic regions. We are unaware of studies on cladocerans conducted in the Tocantins-Araguaia hydrographic region. We reported 17 new records in the Pantanal samples (Paraguay hydrographic region). Overall, richness estimates reveal that 72.6% of the state's cladoceran fauna is already known, while for the Paraguay hydrographic region this estimate is 72.2%. In general, the cladocerans from the Amazon and Paraguay regions did not differ. Our findings allow us to infer the need for further studies in the different hydrographic regions found in Mato Grosso in order to improve the knowledge of cladoceran biodiversity. We suggest a greater sampling effort, particularly in the littoral zone of aquatic ecosystems in this state, which can harbor great biodiversity.
{"title":"Cladocera (Crustacea: Branchiopoda) from the state of Mato Grosso, Brazil","authors":"Maiara Tábatha da Silva Brito, L. P. Diniz, U. M. Pozzobom, V. Landeiro, F. Sousa","doi":"10.1051/limn/2020005","DOIUrl":"https://doi.org/10.1051/limn/2020005","url":null,"abstract":"Studies on Cladocera biodiversity in Brazilian freshwater ecosystems are intensifying. However, the fauna of some hydrographic regions is still poorly known. We investigated the richness and species composition of cladocerans in lakes of the Pantanal from the state of Mato Grosso (Paraguay hydrographic region), Brazil. In addition, we cataloged the known cladoceran species in each hydrographic region of the state. Occurrence data were obtained from the literature and samples collected from 50 lakes in the northern Pantanal. We recorded 120 cladoceran species from eight families in the state of Mato Grosso. The occurrence of these species was recorded in the Amazon and Paraguay hydrographic regions. We are unaware of studies on cladocerans conducted in the Tocantins-Araguaia hydrographic region. We reported 17 new records in the Pantanal samples (Paraguay hydrographic region). Overall, richness estimates reveal that 72.6% of the state's cladoceran fauna is already known, while for the Paraguay hydrographic region this estimate is 72.2%. In general, the cladocerans from the Amazon and Paraguay regions did not differ. Our findings allow us to infer the need for further studies in the different hydrographic regions found in Mato Grosso in order to improve the knowledge of cladoceran biodiversity. We suggest a greater sampling effort, particularly in the littoral zone of aquatic ecosystems in this state, which can harbor great biodiversity.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"8 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86888923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The intensity of transpiration depends on many environmental factors including light, temperature, wind, and air humidity. By eliminating the variation of these factors under laboratory conditions, an attempt was made to indicate the intensity of this process among different species of helophytes and are there any factors limiting this process. We performed a field study of some shallow lakes to answer the question: what is the role of emergent macrophytes in evapotranspiration in lakes with different trophy and surface. Field works were carried out in the shallow littoral at the peak of the growing season. Under laboratory conditions five species were analysing in respect of water uptake. Under laboratory conditions, the width, length and number of leaves as well as the mass and diameter of the stems of respective species had the most significant effect on the uptake of water by helophytes. The length of the plant was a characteristic with the least significant impact on water uptake. The presence of inflorescence was highly negatively correlated with the amount of water taken up by the plants. This phenomenon may slow down the process of water uptake by plants. Among the analyzed factors affecting the uptake of water in the shallow lakes of the Łęczna-Włodawa Lake District, the most important effect was the area of rushes, their density and lake trophic type. In contrast, the type of lake supply, surface of the lake and the variety of helophytes proved to be irrelevant to the amount of water uptake. Helophytes play a significant role in the uptake of water. The share of Typha rushes significantly increases transpiration.
{"title":"Share of rushes in water uptake in shallow lakes in eastern Poland","authors":"J. Sender, M. Różańska-Boczula, A. Grzywna","doi":"10.1051/limn/2020003","DOIUrl":"https://doi.org/10.1051/limn/2020003","url":null,"abstract":"The intensity of transpiration depends on many environmental factors including light, temperature, wind, and air humidity. By eliminating the variation of these factors under laboratory conditions, an attempt was made to indicate the intensity of this process among different species of helophytes and are there any factors limiting this process. We performed a field study of some shallow lakes to answer the question: what is the role of emergent macrophytes in evapotranspiration in lakes with different trophy and surface. Field works were carried out in the shallow littoral at the peak of the growing season. Under laboratory conditions five species were analysing in respect of water uptake. Under laboratory conditions, the width, length and number of leaves as well as the mass and diameter of the stems of respective species had the most significant effect on the uptake of water by helophytes. The length of the plant was a characteristic with the least significant impact on water uptake. The presence of inflorescence was highly negatively correlated with the amount of water taken up by the plants. This phenomenon may slow down the process of water uptake by plants. Among the analyzed factors affecting the uptake of water in the shallow lakes of the Łęczna-Włodawa Lake District, the most important effect was the area of rushes, their density and lake trophic type. In contrast, the type of lake supply, surface of the lake and the variety of helophytes proved to be irrelevant to the amount of water uptake. Helophytes play a significant role in the uptake of water. The share of Typha rushes significantly increases transpiration.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"53 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81235116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microcystis aeruginosa is a potentially toxic bloom-forming freshwater cyanobacterium, usually found in eutrophic water bodies worldwide. The present study reports the occurrence of Microcystis aeruginosa and its bloom in freshwater ponds along central Kerala (south India). Monitoring of cyanobacterial blooms was conducted from May 2019 to February 2020 along the aquatic ecosystems of central Kerala and the M. aeruginosa blooms were recorded from two freshwater ponds of Kochi. Massive blooms of M. aeruginosa was observed during the period prior to summer monsoon (May) with an abundance of 1.17 × 106 cells L‑1 (Station 1) and during early summer (February) latter being more thick scum (2 × 108 cells L‑1) with high chlorophyll a. Dense aggregates of M. aeruginosa scums were more prevalent during the periods characterised by higher Surface Water Temperature (SWT). The nutrient characteristic pattern of the study area showed the abundance of M. aeruginosa correlated very well with higher dissolved nitrate (96.7 μmol L‑1) and phosphate (19.88 μmol L‑1) concentrations. Thus in the stable freshwater ponds with higher SWT and nutrients were the major factors influencing the growth and abundance of the cyanobacteria M. aeruginosa. Toxicological studies conducted revealed that the Microcystis bloom was hepatotoxic, inflicting fish mortality.
铜绿微囊藻是一种具有潜在毒性的淡水蓝藻，通常存在于全球富营养化水体中。本研究报道了铜绿微囊藻在印度南部喀拉拉邦中部的淡水池塘中的发生及其水华。2019年5月至2020年2月，沿着喀拉拉邦中部的水生生态系统对蓝藻华进行了监测，并在科钦的两个淡水池塘记录了铜绿假单胞菌华。在夏季风前(5月)观察到铜绿假单胞菌的大量繁殖，丰度为1.17 × 106细胞L - 1(1号站)，而在初夏(2月)，铜绿假单胞菌的浮皮更厚(2 × 108细胞L - 1)，叶绿素a较高。在地表水温较高的时期，铜绿假单胞菌的浮皮密集聚集更为普遍。研究区绿脓杆菌的丰度与较高的溶解硝酸盐(96.7 μmol L - 1)和磷酸盐(19.88 μmol L - 1)浓度密切相关。因此，在稳定的淡水池塘中，较高的SWT和营养物是影响绿脓杆菌生长和丰度的主要因素。进行的毒理学研究表明，微囊藻华具有肝毒性，可导致鱼类死亡。
{"title":"Occurrence of potentially toxic cyanobacteria Microcystis aeruginosa in aquatic ecosystems of central Kerala (south India)","authors":"Renju Mohan, T. Sathish, K. Padmakumar","doi":"10.1051/limn/2020015","DOIUrl":"https://doi.org/10.1051/limn/2020015","url":null,"abstract":"Microcystis aeruginosa is a potentially toxic bloom-forming freshwater cyanobacterium, usually found in eutrophic water bodies worldwide. The present study reports the occurrence of Microcystis aeruginosa and its bloom in freshwater ponds along central Kerala (south India). Monitoring of cyanobacterial blooms was conducted from May 2019 to February 2020 along the aquatic ecosystems of central Kerala and the M. aeruginosa blooms were recorded from two freshwater ponds of Kochi. Massive blooms of M. aeruginosa was observed during the period prior to summer monsoon (May) with an abundance of 1.17 × 106 cells L‑1 (Station 1) and during early summer (February) latter being more thick scum (2 × 108 cells L‑1) with high chlorophyll a. Dense aggregates of M. aeruginosa scums were more prevalent during the periods characterised by higher Surface Water Temperature (SWT). The nutrient characteristic pattern of the study area showed the abundance of M. aeruginosa correlated very well with higher dissolved nitrate (96.7 μmol L‑1) and phosphate (19.88 μmol L‑1) concentrations. Thus in the stable freshwater ponds with higher SWT and nutrients were the major factors influencing the growth and abundance of the cyanobacteria M. aeruginosa. Toxicological studies conducted revealed that the Microcystis bloom was hepatotoxic, inflicting fish mortality.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"27 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77329430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-15DOI: 10.14302/ISSN.2691-3208.IJLI-19-2853
E. Radwan, Amel Hassan, W. Lotfy, Ahmed Abd El-Mawgood, H. Mashaal
This study was conducted to evaluate the prevalence of intestinal parasite in schoolchildren in Damanhur, Egypt and some of its villages. The pathogenic enteric protozoa have been progressively involved in bargaining the soundness of a great many individuals, for the most part in creating nations. Mediations are being set up to control the dreariness and mortality because of these protozoan contaminations. A portion of these mediations target school going kids with regards to class based wellbeing intercession. The present examination concentrated on exploring the commonness of intestinal protozoan contaminations among younger students chose networks comprising of urban, urban-poor and per urban settlements in the Damanhour and a few towns. In the present work Giardia lamblia was the second usually identified protozoan with a diseases rate 10.4% among the analyzed cases. In the present examination generally speaking level of parasitic contaminations among the kids was 57.3%. It's viewed as Enterobius vermicularis was the most usually identified protozoan as it spoke to 4.1% of the parasitic diseases in the considered cases pursued by Ascaris lumbricoides; 1.4% and Giardia lamblia contaminations as they spoke to 0.6%; separately. The protozoa like Giardia and Cryptosporidium are regularly present in surface waters and cause episodes in this manner legitimately affecting human wellbeing.
{"title":"The Prevalence of Intestinal Parasite Infection in El Behara Schoolchildren.","authors":"E. Radwan, Amel Hassan, W. Lotfy, Ahmed Abd El-Mawgood, H. Mashaal","doi":"10.14302/ISSN.2691-3208.IJLI-19-2853","DOIUrl":"https://doi.org/10.14302/ISSN.2691-3208.IJLI-19-2853","url":null,"abstract":"This study was conducted to evaluate the prevalence of intestinal parasite in schoolchildren in Damanhur, Egypt and some of its villages. The pathogenic enteric protozoa have been progressively involved in bargaining the soundness of a great many individuals, for the most part in creating nations. Mediations are being set up to control the dreariness and mortality because of these protozoan contaminations. A portion of these mediations target school going kids with regards to class based wellbeing intercession. The present examination concentrated on exploring the commonness of intestinal protozoan contaminations among younger students chose networks comprising of urban, urban-poor and per urban settlements in the Damanhour and a few towns. In the present work Giardia lamblia was the second usually identified protozoan with a diseases rate 10.4% among the analyzed cases. In the present examination generally speaking level of parasitic contaminations among the kids was 57.3%. It's viewed as Enterobius vermicularis was the most usually identified protozoan as it spoke to 4.1% of the parasitic diseases in the considered cases pursued by Ascaris lumbricoides; 1.4% and Giardia lamblia contaminations as they spoke to 0.6%; separately. The protozoa like Giardia and Cryptosporidium are regularly present in surface waters and cause episodes in this manner legitimately affecting human wellbeing.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"4 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89833278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guojia Huang, Yushun Chen, Xiaoqing Wang, R. Hughes, L. Xu
Monitoring the ecological status of drinking water reservoirs is very important for assessing risks to the safety of drinking water supplies. Because of the huge number of potential organic and inorganic contaminants in water, we focused our study on common water quality variables and three ecological indices. In this study, we used the modified Carlson trophic status index, Shannon diversity index, and the phytoplankton functional group index to assess the changing ecological status of Zhushuqiao Reservoir, a drinking water source in central China. Stratified water sampling for abiotic and biotic variables was conducted bimonthly from April 2016 to February 2017. All three indices indicated that upper reservoir water quality and ecological condition were worse than those in the lower reservoir. Also, the dominant phytoplankton species in the upper reservoir differed significantly from those in the lower reservoir. The reservoir was eutrophic from June to October, especially in June. During the other months, it was mesotrophic, with the best water quality in winter. Water temperature was the main driver of seasonal changes in both biotic and abiotic indicators, although hydrological condition also affected water quality. Total phosphorus (TP) was the limiting factor for phytoplankton, but phytoplankton biomass increased greatly when both TP and total nitrogen increased. Each index had weaknesses; but applying all three together yielded a comprehensive ecological assessment of Zhushuqiao Reservoir and could do so for other similar reservoirs.
{"title":"Using multiple indicators to assess spatial and temporal changes in ecological condition of a drinking water reservoir in central China","authors":"Guojia Huang, Yushun Chen, Xiaoqing Wang, R. Hughes, L. Xu","doi":"10.1051/LIMN/2019009","DOIUrl":"https://doi.org/10.1051/LIMN/2019009","url":null,"abstract":"Monitoring the ecological status of drinking water reservoirs is very important for assessing risks to the safety of drinking water supplies. Because of the huge number of potential organic and inorganic contaminants in water, we focused our study on common water quality variables and three ecological indices. In this study, we used the modified Carlson trophic status index, Shannon diversity index, and the phytoplankton functional group index to assess the changing ecological status of Zhushuqiao Reservoir, a drinking water source in central China. Stratified water sampling for abiotic and biotic variables was conducted bimonthly from April 2016 to February 2017. All three indices indicated that upper reservoir water quality and ecological condition were worse than those in the lower reservoir. Also, the dominant phytoplankton species in the upper reservoir differed significantly from those in the lower reservoir. The reservoir was eutrophic from June to October, especially in June. During the other months, it was mesotrophic, with the best water quality in winter. Water temperature was the main driver of seasonal changes in both biotic and abiotic indicators, although hydrological condition also affected water quality. Total phosphorus (TP) was the limiting factor for phytoplankton, but phytoplankton biomass increased greatly when both TP and total nitrogen increased. Each index had weaknesses; but applying all three together yielded a comprehensive ecological assessment of Zhushuqiao Reservoir and could do so for other similar reservoirs.","PeriodicalId":7903,"journal":{"name":"Annales De Limnologie-international Journal of Limnology","volume":"124 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2019-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86437094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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