Trophic Status of Lake Phewa and Kulekhani Reservoir, Nepal

2021 ◽  
Vol 18 (3) ◽  
pp. 49-57
Author(s):  
Smriti Gurung ◽  
Babi Kumar Kafle ◽  
Bed Mani Dahal ◽  
Milina Sthapit ◽  
Nani Raut ◽  
...  
Keyword(s):  
Trophic State ◽  
Trophic Status ◽  
Secchi Depth ◽  
Sustainable Use ◽  
Water Bodies ◽  
Limiting Factor ◽  
Trophic State Index ◽  
Post Monsoon ◽  
State Index ◽  
Lake Phewa

Eutrophication is one of the growing environmental concerns and is affecting and compromising freshwater bodies across the world making the trophic status assessment of water bodies crucial for their restoration and sustainable use. This paper describes the trophic status of Lake Phewa and Kulekhani Reservoir from Nepal. Sampling was conducted during October 2017 (post-monsoon), April 2018 (Pre-monsoon), July 2018 (Monsoon) and February 2019 (Winter). Trophic State Index (TSI) as given by Carlson (1977) and Trophic State Index Deviation given by Carlson (1991) were estimated to assess trophic status and deviations between the Trophic State Indices. One-way analysis of variance showed significant seasonal variation (p < 0.05) in Secchi depth, total phosphorus (TP), TSI in both the water bodies. Both the water bodies were classified as eutrophic during pre-monsoon and post-monsoon, and hypereutrophic during the monsoon indicating the increased flow of allochthonous inputs from their respective catchments. Non-algal turbidity was found to be the limiting factor for productivity. There is a need for sustainable watershed management in order to reduce the nutrients runoff and accumulation in the water bodies.

scholarly journals Assessment of Trophic Responses of a Reservoir to Seasonal and Annual Variations in Monsoon

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2117
Author(s):  
Su-mi Kim ◽  
Hyun-su Kim
Keyword(s):  
Water Quality ◽  
Trophic State ◽  
Monsoon Season ◽  
Phytoplankton Growth ◽  
Phosphorus Loading ◽  
Nutrient Concentrations ◽  
Trophic State Index ◽  
Post Monsoon ◽  
Post Monsoon Season ◽  
State Index

The variations in water quality parameters and trophic status of a multipurpose reservoir in response to changing intensity of monsoon rain was investigated by applying a trophic state index deviation (TSID) analysis and an empirical regression model to the data collected in two periods from 2014 to 2017. The reservoir in general maintained mesotrophic conditions, and Carlson’s trophic state index (TSIc) was affected most by TSITP. Nutrient concentrations, particularly phosphorus, did not show strong correlations with precipitation, particularly in the period with weak monsoon, and a significant increase in total phosphorus (TP) was observed in Spring 2015, indicating the possibility of internal phosphorus loading under decreased depth and stability of water body due to a lack of precipitation. TSIChl was higher than TSISD in most data in period 1 when a negligible increase in precipitation was observed in the monsoon season while a significant fraction in period 2 showed the opposite trend. Phytoplankton growth was not limited by nutrient limitation although nutrient ratios (N/P) of most samples were significantly higher than 20, indicating phosphorus-limited condition. TSID and regression analysis indicated that phytoplankton growth was limited by zooplankton grazing in the Spring, and that cell concentrations and community structure in the monsoon and post-monsoon season were controlled by the changing intensity of the monsoon, as evidenced by the positive and negative relationships between community size and cyanobacterial population with the amount of precipitation in the Summer, respectively. The possibility of contribution from internal loading and an increase in cyanobacterial population associated with weak monsoon, in addition to potential for nutrient enrichment in the post-monsoon season, implies a need for the application of more stringent water quality management in the reservoir that can handle all potential scenarios of eutrophication.

scholarly journals Trophic Status and Phytoplankton Limitation Conditions in a Few Bulgarian and Hungarian Danube River Wetlands

2016 ◽  
Vol 18 (2) ◽  
pp. 19-28
Author(s):  
Roumen Kalchev ◽  
Árpád Berczik ◽  
Michaela Beshkova ◽  
Mária Dinka ◽  
Hristina Kalcheva ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Trophic State ◽  
Trophic Status ◽  
Danube River ◽  
Trophic State Index ◽  
Secchi Disk ◽  
State Index

Abstract The phytoplankton limitation conditions in a few Bulgarian and Hungarian wetlands and in two more sampling sites, one for each Danube stretch, were investigated by means of trophic state index of Carlson (1977) for phytoplankton chlorophyll-a (CHL), Secchi disk depths (SD), total phosphorus (TP), and total nitrogen (TN) concentrations. Phytoplankton of both river sites was not limited by non-algal turbidity, nor was they phosphorus and nitrogen limited. In summer months the studied wetlands were predominantly nitrogen limited, while in spring and autumn limitation by non-algal turbidity prevailed.

Assessment of Trophic Status for East Al-Hammar Marsh Using Trophic State Index (TSI)

2015 ◽  
Vol 28 (1) ◽  
pp. 73-81
Author(s):  
Azhar A. Al-Saboonchi ◽  
A. R. M. Mohamed ◽  
Fadia khalid
Keyword(s):  
Trophic State ◽  
Trophic Status ◽  
Trophic State Index ◽  
State Index

scholarly journals Assessing trophic status of Suoi Hai Reservoir using Carlson’s Trophic State Index

2021 ◽  
Author(s):  
Linh Nguyen Thuy ◽  
Ha Nguyen Thi Thu ◽  
Thao Nguyen Thien Phuong ◽  
Vinh Pham Quang
Keyword(s):  
Total Phosphorus ◽  
Trophic State ◽  
Trophic Status ◽  
Anthropogenic Activities ◽  
Treatment Plant ◽  
Anthropogenic Sources ◽  
Trophic State Index ◽  
Nutrient Inputs ◽  
Space And Time ◽  
State Index

The water quality of Suoi Hai reservoir, the largest reservoir in Hanoi city, is being threatened by human activities of the surrounding area, as reported by the press. The trophic status of the reservoir is the result of both natural eutrophication and nutrient inputs from anthropogenic sources, particularly the leachate from a lakeside waste treatment plant. This study aims to identify the trophic status of the Suoi Hai reservoir and the changes of water trophic state over space and time. Data of chlorophyll-a concentration, total phosphorus, and Secchi disk depth from 51 sites during three field campaigns in October 2019, August 2020, and March 2021 was used to calculate Carlson’s trophic state index (CTSI). Resultant CTSI (ranged from 60 to 72) allows classifying Suoi Hai reservoir as highly eutrophic water. Its variations in space and time provided evidence for an influence of anthropogenic activities on the reservoir trophic state. Analysis of the trophic state index deviations suggested that total phosphorus is the key factor that influenced the reservoir trophic state. Therefore, managing the anthropogenic nutrient inputs load to the reservoir should be a critical task to control eutrophication in Suoi Hai Reservoir at present. 

scholarly journals Eutrophication Factor Analysis Using Carlson Trophic State Index (CTSI) Towards Non-Algal Impact Reservoirs in Taiwan

2021 ◽  
Author(s):  
Jr-Lin Lin ◽  
Arthur Karangan ◽  
Ying Min Huang ◽  
Shyh-Fang Kang
Keyword(s):  
Drinking Water ◽  
Influencing Factors ◽  
Trophic State ◽  
Secchi Depth ◽  
Growth Potential ◽  
Trophic State Index ◽  
Water Reservoirs ◽  
Chl A ◽  
Eutrophication Potential ◽  
State Index

Abstract Carlson trophic state index (CTSI) has been commonly adopted to assess the eutrophication potential of reservoirs or lakes in water quality management. This study aims to analyze the influencing factors of CTSI-based eutrophication by using Pearson correlation analysis and principal component analysis (PCA) with long-term data from 2008 to 2019 on 21 drinking water reservoirs in Taiwan. The trophic state index (TSI) deviation indicates that most drinking water reservoirs in Taiwan, around 45.5% of statistical data fall into non-algal turbidity with surplus phosphorus, especially in the spring and winter season. Besides, there are about 78 % of total collected data show that TSI (Chl-a) is less than TSI (SD) due to the small particulate predominance. On the other hand, three TSI variables (Secchi depth (SD), total phosphorus (TP) and chlorophyll-a (Chl-a)) of CTSI exhibits insignificant correlation to each other in most cases. At such a condition, the probability of eutrophication (TSI>50) based on TSI (SD) is 63%, while it is only as low as 20% based on TSI (TP) and TSI (Chl-a). The influencing factors of eutrophication variables by suspended solids (SS) composition and turbidity have shown that the SD is strongly influenced by non-algal SS. The deviations of three TSI have shown that the highest algae-induced eutrophication potential occurs in the summer season. In addition, the TP is the most significant loading factor of algae-induced eutrophication for drinking water reservoirs. It is concluded that the CTSI has limited applicability to identify the trophic status of drinking water reservoirs in Taiwan in the presence of sustainable non-algal turbidity comparative Chl-a that completely represents algal growth potential (AGP).

scholarly journals Assessment of Water Quality Based on Trophic Status and Nutrients-Chlorophyll Empirical Models of Different Elevation Reservoirs

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3640
Author(s):  
Md Mamun ◽  
Usman Atique ◽  
Kwang-Guk An
Keyword(s):  
Water Quality ◽  
Trophic State ◽  
Trophic Status ◽  
Water Clarity ◽  
Empirical Models ◽  
Cyanobacterial Blooms ◽  
Anthropogenic Factors ◽  
Trophic State Index ◽  
Chl A ◽  
State Index

Water quality degradation is one of the most pressing environmental challenges in reservoirs around the world and makes the trophic status assessment of reservoirs essential for their restoration and sustainable use. The main aims of this study were to determine the spatial variations in water quality and trophic state of 204 South Korean reservoirs at different altitude levels. The results demonstrated mean total phosphorus (TP), chlorophyll-a (CHL-a), total suspended solids (TSS), organic matter indicators (chemical oxygen demand: COD; total organic carbon: TOC), water temperature (WT), and electrical conductivity (EC) remain consistently higher in the very lowland reservoirs (VLLR) than those in other altitudes, due to sedimentary or alluvial watersheds. The average TP and CHL-a levels in VLLR crossed the limit of the eutrophic water, symptomizing a moderate risk of cyanobacterial blooms. Empirical models were developed to identify critical variables controlling algal biomass and water clarity in reservoirs. The empirical analyses of all reservoir categories illustrated TP as a better predictor of CHL-a (R2 = 0.44, p < 0.01) than TN (R2 = 0.02, p < 0.05) as well as showed strong P-limitation based on TN:TP ratios. The algal productivity of VLLR (R2 = 0.61, p < 0.01) was limited by phosphorus, while highland reservoirs (HLR) were phosphorus (R2 = 0.23, p < 0.03) and light-limited (R2 = 0.31, p < 0.01). However, TSS showed a highly significant influence on water clarity compared to TP and algal CHL-a in all reservoirs. TP and TSS explained 47% and 34% of the variance in non-algal turbidity (NAT) in HLR. In contrast, the TP and TSS variances were 18% and 29% in midland reservoirs (MLR) and 32% and 20% in LLR. The trophic state index (TSI) of selected reservoirs varied between mesotrophic to eutrophic states as per TSI (TP), TSI (CHL-a), and TSI (SD). Mean TSI (CHL-a) indicated all reservoirs as eutrophic. Trophic state index deviation (TSID) assessment also complemented the phosphorus limitation characterized by the blue-green algae (BGA) domination in all reservoirs. Overall, reservoirs at varying altitudes reflect the multiplying impacts of anthropogenic factors on water quality, which can provide valuable insights into reservoir water quality management.

scholarly journals Assessment of Trophic State of Lakes: A Case of Mansi Ganga Lake in India

1970 ◽  
Vol 6 ◽  
pp. 65-72 ◽  
Author(s):  
M. P. Sharma ◽  
Arun Kumar ◽  
Shalini Rajvanshi
Keyword(s):  
Drinking Water ◽  
Lake Water ◽  
Trophic State ◽  
Secchi Depth ◽  
Trophic State Index ◽  
Energy And Environment ◽  
Conservation Measure ◽  
Drinking Water Resources ◽  
State Index ◽  
Work Done

Due to rapid growth of population coupled with urbanization, the water bodies, especially, rivers, lakes, ponds, reservoirs etc are deteriorating due to heavy pollutational stresses resulting in the scarcity of drinking water resources. The present paper attempts to review the work done on the development of TSI for assessment of trophic state of lakes and applicability of most important TSI methods for Indian lakes. The paper also deals with the revival of Mansi Ganga Lake in Mathura, especially, assessment of its trophic state based on the data collected for 2006-09. The results indicated that the lake was oligotrophic during 2006 which has become mesotrophic in the year 2008 showing increase in pollution. After the chemical treatment for the removal of algae, the lake water was drained and results of sampling done in 2009 (pre-monsoon) indicated it to be eutrophic. These calls for its immediate revival and accordingly, the conservation measure are suggested.Key words: Eutrophication; Trophic State Index (TSI); Total Phosphorus (TP); Secchi depth (SD); Chlorophyll ‘a’ (Chl’a’)DOI: 10.3126/hn.v6i0.4198Hydro Nepal Journal of Water, Energy and Environment Vol. 6, January 2010Page: 65-72Uploaded Date: 24 January, 2011

scholarly journals Trophic Status In Joto Reservoir, Lamongan

2021 ◽  
Vol 19 (2) ◽  
pp. 354
Author(s):  
Norma Aprilia Fanni ◽  
Fuquh Rahmat Shaleh
Keyword(s):  
Random Sampling ◽  
Trophic State ◽  
Trophic Status ◽  
Trophic State Index ◽  
State Index

Waduk Joto merupakan waduk yang berada di Kabupaten Lamongan yang biasa digunakan oleh masyarakat sekitar untuk aktifitas sehari-hari. Selain itu aliran air waduk juga digunakan untuk kegiatan perikanan dan pertanian. Dalam pengelolaan suatu perairan yang lestari dan berkelanjutan diperlukan informasi dasar mengenai tingkat kesuburan perairan guna pemanfaatan yang tepat. Penelitian ini bertujuan untuk mengetahui kualitas air dan status kesuburan perairan di Waduk Joto Kabupaten Lamongan. Metode pengumpulan data menggunakan purposive random sampling pada tiga stasiun yaitu bagian inlet, tengah, dan outlet. Penentuan status kesuburan perairan berdasarkan perhitunganmenggunakan Carlson Trophic State Index (TSI). Pengambilan sampel air dilakukan dengan interval waktu satu bulan sekali selama 3 bulan pada bulan Desember 2020 sampai Februari 2021. Parameter yang diamati meliputi suhu, kecerahan, pH, salinitas, oksigen terlarut (DO), nitrat, total fosfat, klorofil-a. Hasil penelitian menunjukkan bahwa status kesuburan perairan Waduk Joto pada bulan Desember 2020 – Februari 2021 berdasarkan TSI Carlson termasuk dalam kategori perairan hipereutrofik dengan nilai sebesar 74. Disarankan untuk melakukan penelitian lanjutan pada musim yang berbeda untuk mengetahui status kesuburan perairan di musim kemarau.

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