Trophic Responses of the Asian Reservoir to Long-Term Seasonal and Interannual Dynamic Monsoon

The main objectives of the study were to determine the trophic response of the temperate reservoir to seasonal and interannual variabilities of monsoon inorganic solids and nutrients along the gradients of the morphologically complex Asian reservoir using long-term datasets between 2000–2018. Nutrient regime (total nitrogen—TN, total phosphorus—TP), total suspended solids (TSS), and chlorophyll-a (CHL-a) were primarily affected by an intensity of summer monsoon and the longitudinal structure of riverine (Rz), transitional (Tz), and lacustrine (Lz) zone. The reservoir is a nitrogen-rich system and the phosphorus content of the water was relatively low, and it had low mean N:P ratios (<40), implying a P-limiting system. The Lz was a highly P-limited zone in comparison to Rz and Tz zone during both drought (2015) and flood year (2011). The TP content was higher in the mainstem (S3) than the embankment (S4 and S6) of the reservoir due to the monsoon river inputs of the nutrients. Nonparametric Mann–Kendall tests indicated that TP decreased over the long-term years in the Rz, while it did not show any trend in Tz, Lz, IT1, and IT2. TN showed an increasing trend in Rz, Tz, Lz, and IT2 except for IT1. The empirical regression model for chlorophyll nutrients showed that CHL-a had a strong positive relationship with TP (R2 = 0.67, p < 0.01) than TN (R2 = 0.06, p < 0.01), supporting the view that algal growth in lentic systems responds to TP enrichment and TP may provide a reliable basis for predicting algal biomass. The seasonality of CHL-a and TP showed a monomodal pattern and indicates that summer TP influences summer algal growth in Tz, Lz, and IT2. The water clarity (SD) of the reservoir was significantly (p < 0.01) influenced by TP (R2 = 0.62), TSS (R2 = 0.67), and CHL-a (R2 = 0.68) rather than TN (R2 = 0.10). The non-algal light attenuation coefficient (Kna) was determined mainly by suspended solids and the monsoon hydrology. The trophic state was much higher when assessments were based on TSI (CHL-a) than on TSI (TP) and TSI (SD). TSI (CHL-a) indicated the eutrophic state of the reservoirs except for the zone of Lz during the premonsoon season. Analysis of trophic state index deviation (TSID) suggested that the blue-green algae dominated the algal community, and the effects of non-algal turbidity and zooplankton grazing were minor in the reservoir.

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Particulate light attenuation in a large subtropical lake

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-172 ◽

1995 ◽

Vol 52 (8) ◽

pp. 1803-1811 ◽

Cited By ~ 20

Author(s):

Karl E. Havens

Keyword(s):

Surface Water ◽

Trophic State ◽

Nutrient Loading ◽

Light Attenuation ◽

Algal Growth ◽

Progressive Increase ◽

Trophic State Index ◽

Littoral Region ◽

Relative Contribution ◽

Total Light

Deviations among Carlson's trophic state index values were used to quantify a 12-year history of seston composition and underwater light attenuation in Lake Okeechobee, Florida, U.S.A. Deviations between chlorophyll a, total phosphorus, and transparency-based trophic state indices indicated that (i) light attenuation is generally dominated by phosphorus-rich abiotic particles; (ii) abiotic light attenuation is maximal in a central lake region overlying soft mud sediments, and minimal in a near-littoral region overlying hard sand; and (iii) there has been a progressive increase in the relative contribution of algal pigments to total light attenuation between 1980 and 1992. Coincident with that 12-year trend, there have been declines in external nitrogen loads, lake water nitrogen:phosphorus ratios, and wind velocities. Surface water temperatures in the lake have significantly increased. Explanations for the trend in light attenuation include (i) more favorable meteorological conditions for algal growth, which increased the contribution of algae to overall light attenuation and (ii) reduced nitrogen:phosphorus ratios favoring proliferation of buoyant cyanobacteria, which are more effectively sampled by surface water monitoring. In either case, the trend did not coincide historically with enhanced nutrient loading, the common cause of algal proliferation in lakes.

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Multivariate Statistical Analysis of Water Quality and Trophic State in an Artificial Dam Reservoir

Water ◽

10.3390/w13020186 ◽

2021 ◽

Vol 13 (2) ◽

pp. 186

Author(s):

Md Mamun ◽

Ji Yoon Kim ◽

Kwang-Guk An

Keyword(s):

Water Quality ◽

Trophic State ◽

Suspended Solids ◽

Oxygen Demand ◽

Quality Parameters ◽

Water Quality Parameters ◽

Trophic State Index ◽

Multivariate Statistical ◽

Chl A ◽

State Index

Paldang Reservoir, located in the Han River basin in South Korea, is used for drinking water, fishing, irrigation, recreation, and hydroelectric power. Therefore, the water quality of the reservoir is of great importance. The main objectives of this study were to evaluate spatial and seasonal variations of surface water quality in the reservoir using multivariate statistical techniques (MSTs) along with the Trophic State Index (TSI) and Trophic State Index deviation (TSID). The empirical relationships among nutrients (total phosphorus, TP; total nitrogen, TN), chlorophyll-a (CHL-a), and annual variations of water quality parameters were also determined. To this end, 12 water quality parameters were monitored monthly at five sites along the reservoir from 1996 to 2019. Most of the parameters (all except pH, dissolved oxygen (DO), and total coliform bacteria (TCB)) showed significant spatial variations, indicating an influence of anthropogenic activities. Principal component analysis combined with factor analysis (PCA/FA) suggested that the parameters responsible for water quality variations were primarily correlated with nutrients and organic matter (anthropogenic), suspended solids (both natural and anthropogenic), and ionic concentrations (both natural and anthropogenic). Stepwise spatial discriminant analysis (DA) identified water temperature (WT), DO, electrical conductivity (EC), chemical oxygen demand (COD), the ratio of biological oxygen demand (BOD) to COD (BOD/COD), TN, TN:TP, and TCB as the parameters responsible for variations among sites, and seasonal stepwise DA identified WT, BOD, and total suspended solids (TSS) as the parameters responsible for variations among seasons. COD has increased (R2 = 0.63, p < 0.01) in the reservoir since 1996, suggesting that nonbiodegradable organic loading to the water body is rising. The empirical regression models of CHL-a-TP (R2 = 0.45) and CHL-a-TN (R2 = 0.27) indicated that TP better explained algal growth than TN. The mean TSI values for TP, CHL-a, and Secchi depth (SD) indicated a eutrophic state of the reservoir for all seasons and sites. Analysis of TSID suggested that blue-green algae dominated the algal community in the reservoir. The present results show that a significant increase in algal chlorophyll occurs during spring in the reservoir. Our findings may facilitate the management of Paldang Reservoir.

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

Water ◽

10.3390/w13243640 ◽

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.

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Evaluation of the Eutrophication levels in Al-Najaf Al-Ashraf lake ,Iraq (Biological and chemical study).

Engineering and Technology Journal ◽

10.30684/etj.v38i10a.1601 ◽

2020 ◽

Vol 38 (10A) ◽

pp. 1531-1538

Author(s):

Suhair R. Al-Sharifi ◽

Salih A. Al-Bakri ◽

Sataa Al-Bayati

Keyword(s):

Heavy Metal ◽

Industrial Waste ◽

Trophic State ◽

Chemical Study ◽

Drainage Water ◽

Trophic State Index ◽

Chl A ◽

Blue Green Algae ◽

State Index ◽

Temporal And Spatial

The present study was conducted because of rapidly increasing pollution in Al-Najaf lake, which is one of the significant shallow lakes of Iraq, lake facing tremendous pressure due to encroachments, discharge of untreated domestic and industrial waste, drainage water from cultivated orchards, dumping of solid waste and illegal diversion of water, and currently it still suffering from these problems and neglect, the lake could be important tourist and recreational place in Governorate if we could preserve it and remove the pollution sources. Study aimed to evaluation the eutrophication status, and plotted by (GIS). Eutrophication is a serious problem in lakes, awareness about the eutrophic status could help in providing a better understanding of the problem. this study conducted to assess temporal and spatial eutrophication index in AL-najaf lake. The eutrophication level of the lake is determined with help of 0 – 100 scale based on (TSI) calculations and (Ta), (Chl-a), (TP), (TN), (Pb) heavy metal, (TSS), (TDS), (pH), (EC), (MPN) and (COD). Lake can be classified according to Carlson as eutrophic (TSI was higher than 80) with dominance of blue green algae, extensive macrophyte problems, while according trophic state index (TSI) classification (TSI), (TP) and (Chl-a), were classified the lake as extremely hyper eutrophic and algal scums

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The evolution of the trophic state of the Palic Lake (Serbia)

Journal of the Serbian Chemical Society ◽

10.2298/jsc091016043g ◽

2010 ◽

Vol 75 (5) ◽

pp. 717-732 ◽

Cited By ~ 5

Author(s):

Ivan Grzetic ◽

Natasa Camprag

Keyword(s):

Trophic State ◽

Algal Growth ◽

Limiting Factor ◽

Trophic State Index ◽

Secchi Disk ◽

Secchi Disk Transparency ◽

Total Phosphorous ◽

Pannonian Plain ◽

State Index

The Palic Lake is a shallow lake typical for the Pannonian Plain. Due inadequate water quality, it was dried out in 1971 and re-established in 1977 and since than its trophicity has been worsening. Investigation of the long-term changes in the trophic state of this lake were tracked over the total phosphorous (TP), total nitrogen (TN), chlorophyll-a and Secchi disk transparency (SD transparency), expressed as the Carlson Trophic State Index (TSI). Regarding the TSI values, the water of the Palic Lake has been constantly evolving from eutrophic to hypereutrophic. TN/TP values < 10 indicate that nitrogen is the limiting factor for algal growth.

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Long-Term Water Quality Patterns in an Estuarine Reservoir and the Functional Changes in Relations of Trophic State Variables Depending on the Construction of Serial Weirs in Upstream Reaches

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182312568 ◽

2021 ◽

Vol 18 (23) ◽

pp. 12568

Author(s):

Namsrai Jargal ◽

Ho-Seong Lee ◽

Kwang-Guk An

Keyword(s):

Water Quality ◽

Organic Matter ◽

Algal Biomass ◽

Trophic State ◽

Suspended Solids ◽

State Variables ◽

Chl A ◽

Functional Changes ◽

Estuarine Reservoir

Water quality degradation is one of the major problems with artificial lakes in estuaries. Long-term spatiotemporal patterns of water quality in a South Korean estuarine reservoir were analyzed using seasonal datasets from 2002 to 2020, and some functional changes in relations of trophic state variables due to the construction of serial weirs in the upper river were also investigated. A total of 19 water quality parameters were used for the study, including indicators of organic matter, nutrients, suspended solids, water clarity, and fecal pollution. In addition, chlorophyll-a (CHL-a) was used to assess algal biomass. An empirical regression model, trophic state index deviation (TSID), and principal component analysis (PCA) were applied. Longitudinal fluctuations in nutrients, organic matter, sestonic CHL-a, and suspended solids were found along the axis of the riverine (Rz), transition (Tz), and lacustrine zones (Lz). The degradation of water quality was seasonally caused by resuspension of sediments, monsoon input due to rainfall inflow, and intensity of Asian monsoon, and was also related to intensive anthropic activities within the catchment. The empirical model and PCA showed that light availability was directly controlled by non-algal turbidity, which was a more important regulator of CHL-a than total nitrogen (TN) and total phosphorus (TP). The TSID supported our hypothesis on the non-algal turbidity. We also found that the construction of serial upper weirs influenced nutrient regime, TSS, CHL-a level, and trophic state in the estuarine reservoir, resulting in lower TP and TN but high CHL-a and high TN/TP ratios. The proportions of both dissolved color clay particles and blue-green algae in the TSID additionally increased. Overall, the long-term patterns of nutrients, suspended solids, and algal biomass changed due to seasonal runoff, turnover time, and reservoir zones along with anthropic impacts of the upper weir constructions, resulting in changes in trophic state variables and their mutual relations in the estuarine reservoir.

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APLIKASI CITRA LANDSAT 8 OLI UNTUK IDENTIFIKASI STATUS TROFIK WADUK GAJAH MUNGKUR WONOGIRI, JAWA TENGAH

MAJALAH ILMIAH GLOBE ◽

10.24895/mig.2017.19-2.633 ◽

2017 ◽

Vol 19 (2) ◽

pp. 113

Author(s):

Kusuma Wardani Laksitaningrum ◽

Wirastuti Widyatmanti

Keyword(s):

Chlorophyll A ◽

Total Phosphorus ◽

Trophic State ◽

Water Clarity ◽

Coefficient Of Determination ◽

Physical Factors ◽

Landsat 8 ◽

Trophic State Index ◽

Landsat 8 Oli ◽

State Index

ABSTRAKWaduk Gajah Mungkur (WGM) adalah bendungan buatan yang memiliki luas genangan maksimum 8800 ha, terletak di Desa Pokoh Kidul, Kecamatan Wonogiri, Kabupaten Wonogiri. Kondisi perairan WGM dipengaruhi oleh faktor klimatologis, fisik, dan aktivitas manusia yang dapat menyumbang nutrisi sehingga mempengaruhi status trofiknya. Tujuan dari penelitian ini adalah mengkaji kemampuan citra Landsat 8 OLI untuk memperoleh parameter-parameter yang digunakan untuk menilai status trofik, menentukan dan memetakan status trofik yang diperoleh dari citra Landsat 8 OLI, dan mengevaluasi hasil pemetaan dan manfaat citra penginderaan jauh untuk identifikasi status trofik WGM. Identifikasi status trofik dilakukan berdasarkan metode Trophic State Index (TSI) Carlson (1997) menggunakan tiga parameter yaitu kejernihan air, total fosfor, dan klorofil-a. Model yang diperoleh berdasar pada rumus empiris dari hasil uji regresi antara pengukuran di lapangan dan nilai piksel di citra Landsat 8 OLI. Model dipilih berdasarkan nilai koefisien determinasi (R2) tertinggi. Hasil penelitian merepresentasikan bahwa nilai R2 kejernihan air sebesar 0,813, total fosfor sebesar 0,268, dan klorofil-a sebesar 0,584. Apabila nilai R2 mendekati 1, maka semakin baik model regresi dapat menjelaskan suatu parameter status trofik. Berdasarkan hasil kalkulasi diperoleh distribusi yang terdiri dari kelas eutrofik ringan, eutrofik sedang, dan eutrofik berat yaitu pada rentang nilai indeks 50,051 – 80,180. Distribusi terbesar adalah eutrofik sedang. Hal tersebut menunjukkan tingkat kesuburan perairan yang tinggi dan dapat membahayakan makhluk hidup lain.Kata kunci: Waduk Gajah Mungkur, citra Landsat 8 OLI, regresi, TSI, status trofikABSTRACTGajah Mungkur Reservoir is an artificial dam that has a maximum inundated areas of 8800 ha, located in Pokoh Kidul Village, Wonogiri Regency. The reservoir’s water conditions are affected by climatological and physical factors, as well as human activities that can contribute to nutrients that affect its trophic state. This study aimed to assess the Landsat 8 OLI capabilities to obtain parameters that are used to determine its trophic state, identifying and mapping the trophic state based on parameters derived from Landsat 8 OLI, and evaluating the results of the mapping and the benefits of remote sensing imagery for identification of its trophic state. Identification of trophic state is based on Trophic State Index (TSI) Carlson (1997), which uses three parameters there are water clarity, total phosphorus, and chlorophyll-a. The model is based on an empirical formula of regression between measurements in the field and the pixel values in Landsat 8 OLI. Model is selected on the highest value towards coefficient of determination (R2). The results represented that R2 of water clarity is 0.813, total phosphorus is 0.268, and chlorophyll-a is 0.584. If R2 close to 1, regression model will describe the parameters of the trophic state better. Based on the calculation the distribution consists of mild eutrophic, moderate eutrophic, and heavy eutrophic that has index values from 50.051 to 80.18. The most distribution is moderate eutrophication, and it showed the high level of trophic state and may harm other living beings.Keywords: Gajah Mungkur Reservoir, Landsat 8 OLI satellite imagery, regression, TSI, trophic state

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Quantum yield of the marine benthic microflora of near-shore coastal Penang, Malaysia

Marine and Freshwater Research ◽

10.1071/mf05007 ◽

2005 ◽

Vol 56 (7) ◽

pp. 1047 ◽

Cited By ~ 3

Author(s):

A. McMinn ◽

S. Sellah ◽

W. A. Wan Ab. Llah ◽

M. Mohammad ◽

F. Md. Sidik Merican ◽

...

Keyword(s):

Primary Production ◽

Suspended Solids ◽

Euphotic Zone ◽

Water Clarity ◽

Quantum Yields ◽

Chl A ◽

Near Shore ◽

High Concentrations ◽

A Minor ◽

Reduced Water

Benthic microalgal communities often contribute more than 30% of the primary production of shallow coastal and estuarine areas. At Muka Head Penang (Pulau Pinang) and the Songsong Islands (Pulau Songsong), Kedah, Malaysia, high concentrations of suspended solids and phytoplankton biomass (10.6 mg Chl a m−3) has reduced water clarity such that the euphotic zone of these areas is less than 2 m and 3 m deep respectively. The benthic microalgal communities, which were composed of the diatom genera Cocconeis, Fragilaria, Paralia and Pleurosigma, had a low biomass, had low maximum quantum yields (0.325 ± 0.129), were poorly adapted to their light environment and were constantly light limited. These characteristics suggest that the benthic microalgal communities were likely to have made only a minor contribution to the total primary production of the area.

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Effects of Environmental Factors on Nutrients Release at Sediment-Water Interface and Assessment of Trophic Status for a Typical Shallow Lake, Northwest China

The Scientific World JOURNAL ◽

10.1155/2013/716342 ◽

2013 ◽

Vol 2013 ◽

pp. 1-16 ◽

Cited By ~ 24

Author(s):

Dekun Hou ◽

Jiang He ◽

Changwei Lü ◽

Ying Sun ◽

Fujin Zhang ◽

...

Keyword(s):

Trophic State ◽

Algal Growth ◽

Northwest China ◽

Trophic State Index ◽

Nitrogen And Phosphorus ◽

Daihai Lake ◽

Terrestrial Source ◽

Limiting Nutrient ◽

State Index

Surface sediment and water samples were collected from Daihai Lake to study the biogeochemical characteristics of nitrogen and phosphorus, to estimate the loads of these nutrients, and to assess their effects on water quality. The contents and spatial distributions of total phosphorus (TP), total nitrogen (TN), and different nitrogen forms in sediments were analyzed. The results showed that concentrations of TN and TP in surface sediments ranged from 0.27 to 1.78 g/kg and from 558.31 to 891.29 mg/kg, respectively. Ratios of C : N ranged between 8.2 and 12.1, which indicated that nitrogen accumulated came mainly from terrestrial source. Ratios of N : P in all sampling sites were below 10, which indicated that N was the limiting nutrient for algal growth in this lake. Effects of environment factors on the release of nitrogen and phosphorus in lake sediments were also determined; high pH values could encourage the release of nitrogen and phosphorus. Modified Carlson’s trophic state index (TSIM) and comprehensive trophic state index (TSIC) were applied to ascertain the trophic classification of the studied lake, and the values ofTSIMandTSICranged from 53.72 to 70.61 and from 47.73 to 53.67, respectively, which indicated that the Daihai Lake was in the stage of hypereutropher.

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Physical and biogeochemical controls on light attenuation in a eutrophic, back-barrier estuary

Biogeosciences Discussions ◽

10.5194/bgd-11-12183-2014 ◽

2014 ◽

Vol 11 (8) ◽

pp. 12183-12221 ◽

Cited By ~ 1

Author(s):

N. K. Ganju ◽

J. L. Miselis ◽

A. L. Aretxabaleta

Keyword(s):

Light Attenuation ◽

Sediment Resuspension ◽

Water Clarity ◽

High Temporal Resolution ◽

Barnegat Bay ◽

Chl A ◽

Seagrass Meadows ◽

Boat Traffic ◽

The Difference ◽

Shallow Estuaries

Abstract. Light attenuation is a critical parameter governing the ecological function of shallow estuaries. In these systems primary production is often dominated by benthic macroalgae and seagrass; thus light penetration to the bed is of primary importance. We quantified light attenuation in three seagrass meadows in Barnegat Bay, New Jersey, a shallow eutrophic back-barrier estuary; two of the sites were located within designated Ecologically Sensitive Areas (ESAs). We sequentially deployed instrumentation measuring photosynthetically active radiation, chlorophyll a (chl a) fluorescence, dissolved organic matter fluorescence (fDOM; a proxy for colored DOM absorbance), turbidity, pressure, and water velocity at 10 min intervals over three week periods at each site. At the southernmost site, where sediment availability was highest, light attenuation was highest and dominated by turbidity and to a lesser extent chl a and CDOM. At the central site, chl a dominated followed by turbidity and CDOM, and at the northernmost site turbidity and CDOM contributed equally to light attenuation. At a given site, the temporal variability of light attenuation exceeded the difference in median light attenuation at the three sites, indicating the need for continuous high-temporal resolution measurements. Vessel wakes, anecdotally implicated in increasing sediment resuspension, did not contribute to local resuspension within the seagrass beds, though frequent vessel wakes were observed in the channels. With regards to light attenuation and water clarity, physical and biogeochemical variables appear to outweigh any regulation of boat traffic within the ESAs.

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