Trophic State Of Water Body Research Articles

New determination of Pediastrum orientale in polar lake sediments and its palaeoecological implications – Reindeer Lake, Bellsund, Spitsbergen

The main component of microfossils in the bottom sediments of Reindeer Lake from Spitsbergen, documenting the almost 8,000-year history of this water body, are algae representing colonies of a very rare species Pediastrum orientale (Skuja) Jankovská et Komárek 1995 with only a very small (lower than 1%) admixture of other green algae species. It has also been recorded in other lake sediments in Spitsbergen. The specimens belong to the morphotype “b” of the species, known previously from the Scandinavian lakes. Due to its unique nature and scarce information on ecological conditions, this study analysed the palaeoenvironmental factors favouring the occurrence of Pediastrum orientale together with an assessment of its bioindication value. The affinity of the species to oligotrophic lakes, where blooms of this alga are observed, was confirmed. The presence of numerous colonies of Pediastrum orientale in fossil lake sediments can provide a rationale for inferring palaeoecological conditions, including the trophic state of water bodies, thus expanding knowledge of their evolutionary directions and documenting key events in the geological history of the catchment. Further studies of lake gyttjas in Spitsbergen should pay more attention to the taxonomic composition of Pediastrum and other green algae, as well as to the determinants of sediment deposition in different lake catchment environments.

Development of an Inexpensive, Rapid Method to Measure Nitrates in Freshwater to Enhance Student Learning

A laboratory experiment was designed and implemented in a STEM teaching laboratory at Michigan State University to engage students in an activity that not only introduced an innovative nitrate detection technique but also addressed one of the negative impacts of climate change, that is, the eutrophication of water bodies. The adverse effects of eutrophication on public health due to the presence of cyanotoxins make it crucial to monitor the trophic state of water bodies, which can be assessed by measuring the nitrate and phosphate concentrations. We developed a rapid method to measure nitrate concentrations in freshwater samples using a Hanna Instruments Checker, which was designed to measure nitrate levels in seawater. We identified the sample matrix that would maximize the accuracy of the Checker instrument for freshwater samples and validated the analytical method via ion chromatography. Students gained knowledge of other aspects of laboratory procedures, such as sample collection, sample storage, and material compatibility, which are often ignored during conventional teaching practices.

Estimating Effects of Natural and Anthropogenic Activities on Trophic Level of Inland Water: Analysis of Poyang Lake Basin, China, with Landsat-8 Observations

The intensification of anthropogenic activities has led to the infiltration of enormous quantities of pollutants into rivers and lakes, resulting in significant deterioration in water quality and a more prominent occurrence of eutrophication. Poyang Lake, the largest freshwater lake in China, is facing a severe challenge related to eutrophication, which seriously threatens the delivery of the ecosystem service and the safety of drinking water. To address this challenge, Landsat-8 Operational Land Imager (OLI) data for the Poyang Lake Basin (PLB) from May 2013 to December 2020 were used. Since inland water bodies with complex optical characteristics, we developed a semi-analytical algorithm to assess the trophic state of the water based on two cruise field measurements in 2016 and 2019. Combining the semi-analytical trophic level index (TLI) with an atmospheric correction model is the most suitable model for OLI images of the PLB, this model was then applied to Landsat-8 time series observations. The trends of the trophic state of water bodies in PLB were revealed, and the annual, quarterly and monthly percentages of eutrophic water bodies were calculated. Natural and anthropogenic factors were then used to explain the changes in the trophic state of the PLB waters. The main findings are as follows: (1) From the 8-year observation results, it can be seen that the variation of trophic level of water in PLB showed obviously spatial and temporal variations, characterized by higher in the north than in the south and higher in winter than in summer. (2) Temperature promoted the growth of harmful algae and plays an essential role in affecting changes in the trophic level of the water. (3) Changes in the trophic level of water bodies in PLB were mainly affected by human activities. The results of spatial and temporal variation of the trophic level of water and the driving factors in PLB can extend our knowledge of water quality degradation and provide essential references for relevant policy-making institutions.

A dataset of the TSI of Hulun Lake in summer, 1986–2020

The Trophic state index (TSI) stands as one of the most direct and effective indices for characterizing the trophic state of water bodies, and the long-time TSI series data are important for monitoring the dynamic shifts in water quality in lakes. In this dataset, we used Landsat-5 TM, Landsat-7 ETM+ and Landsat-8 OLI as data sources, and crafted an Algal biomass index (ABI) to investigate its responsiveness to TSI. And through rigorous analysis, we estimated the TSI time series of Hulun Lake for 35 years from 1986 to 2020. Furthermore, we generated spatial maps depicting the mean TSI values in summer. The results revealed a distinctive spatial pattern, characterized by elevated TSI levels in the southwestern region and lower levels in the northeast of Hulun Lake during the summer season. Moreover, there was a noticeable discrepancy between the shoreline and the central area of the lake, with higher TSI values near the shore and lower values in the lake's center. To ensure the reliability and accuracy of the results, we compared the TSI derived from the OLI and the TSI based on measured reflectance ratios, which shows that the root mean square error (RMSE) of less than 2.39, and the mean absolute percentage error (MAPE) of less than 3.53%. The dataset is provided in *.tif format with a spatial resolution of 30 m. Users can leverage professional GIS software to view and edit, or use the relevant python packages or R languages for advanced data processing. The spatial and temporal variation characteristics of TSI reflected in this dataset can provide effective data support for water quality monitoring and ecological protection in Hulun Lake area.

Anthropogenic eutrophication of lakes Turgoyak and Bolshoi Kisegach

The article examines the long-term dynamics of three main indicators of the trophic state of water bodies (transparency, phosphorus concentration and oxygen regime) for the natural oligotrophic lakes of the Southern Urals: Turgoyak and Bolshoi Kisegach. These lakes have a similar history of anthropogenic development (water intake and recreation). At the same time, the lakes have a different degree of anthropogenic transformation in connection with different volumes of incoming nutrients, which affect the quality of lake waters and natural recreational potential.

Fuzzy logic approach for the assessment of trophic state of water bodies

Eutrophication has emerged as one of the main threats to surface water bodies. The parameters for assessing eutrophication are not generally measured regularly from the lakes of India as part of monitoring programmes and it is necessary to express the trophic status in terms of secondary indicator variables that are included in the routine analysis by the State/Central government. In this paper, the trophic status of Ashtamudi Lake has been studied, considering its international importance and socio-economic relevance. The cause and response variables such as total phosphorus, Secchi disc depth, chlorophyll-a and the secondary indicator variables such as pH, turbidity, DO, EC, Salinity, TDS and BOD were analysed during the pre-monsoon season. The lake was predominantly classified as eutrophic, with some areas coming under a hypereutrophic state. A comparison was made among the five methods of water quality index by the use of secondary indicator variables to identify the appropriate method for simulating trophic status and the WQI based on the logarithmic method considering pH, turbidity, DO and BOD was identified to predict the trophic state very well. Further, the application of numerical strategy such as fuzzy logic was used to determine water quality indexes and trophic status, which can define the quality of a water body as a consequence of the variation of environmental parameters. The developed approach was further validated by using historical data for the years 2013–2015, which were regularly monitored by the Kerala State Pollution Control Board. The trophic state predicted by the approach was found to be in agreement with that estimated using Carlson's method. Thus the developed model, based on secondary indicator parameters that are readily available from government agencies, can be used to assess the trophic state of lakes, thereby assisting policy makers to frame regulations to minimize eutrophication.

A meta-analysis of benthic rotifer community structure as a function of lake trophic state

Our understanding of the ecological drivers that control community structure of benthic rotifers is poorly known. By reviewing 21 papers on freshwater benthic rotifers we compiled an inventory of an additional 258 species, 27 genera, and six families not previously listed in the review of benthic, lotic rotifers by Ricci and Balsamo (Freshw Biol 44:15–28, 2000). This raises the number of reported benthic species to 416, ~ 23% of all rotifers. Using selected papers within our dataset we tested two hypotheses: (1) Within lakes of different trophic state benthic rotifer communities differ in their species composition and (2) because rotifer trophi types reflect strong specificity for certain foods, there is a difference in the distribution of trophi types in lakes of different trophic state. We found that the trophic state of water bodies influences species composition of benthic rotifers, but there was no significant difference in the distribution of their trophi types. To aid in understanding community assembly of benthic rotifers, we provide a list of knowledge gaps that future studies could address.

Assessment of Landsat 5 Images Atmospherically Corrected with LEDAPS in Water Quality Time Series

The main objective of this work is to assess and use Landsat TM5 for the inventory and study of the evolution of water quality in gravel pit ponds within the natural park, Parque Regional del Sureste (PRSE), from 1984 to 2011. First, the normalized difference water index (NDWI) was applied to 230 Landsat TM5 images to distinguish water and non-water information. Next, the surface reflectance derived from Landsat TM5 images atmospherically corrected with the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) was compared to water-leaving reflectance measured in the field, showing a significant overestimation of surface reflectance derived from Landsat data. Thus, a new regression equation was proposed linking the in situ Secchi depth (SD) measurements to surface reflectance measured by Landsat 5. This regression was validated and subsequently applied to every image, providing an SD value for each pixel in the time series. Finally, the retrieved SD values were used to compute the trophic state of water bodies according to the Organization for Economic Co-operation and Development (OECD) classification. The results show an increase in the surface area of water bodies in the PRSE from 1984 to 2006, as well as an improvement in their water quality.

Monitoring of Marine Biofilm Formation Dynamics at Submerged Solid Surfaces With Multitechnique Sensors

Biofouling on artificial and biotic solid substrata was studied in several locations in the Baltic Sea brackish water (Gulf of Gdansk) during a three-year period with contact angle wettability, confocal microscopy and photoacoustic spectroscopy techniques. As a reference, the trophic state of water body was determined from chemical analyses according to the following parameters: pH, dissolved O2, phosphate, nitrite, nitrate, ammonium etc. concentrations and further correlated to the determined biofilm characterizing parameters by means of Spearman’s rank correlation procedure. Biofilm adhesive surface properties (surface free energy, work of adhesion etc.) were obtained with the contact angle hysteresis (CAH) approach using an automatic captive bubble solid surface wettability sensor assigned for in-situ, on-line and quasi-continuous measurements of permanently submerged samples (Pogorzelski et al., 2013, Pogorzelski and Szczepańska, 2014). Structural and morphological biofilm features (biovolume, substratum coverage, area to volume ratio, spatial spreading, mean thickness and roughness) were determined from confocal reflection microscopy (COCRM) data. Photosynthetic properties (photosynthetic energy storage (ES), photoacoustic amplitude and phase spectra) of biofilm communities exhibited a seasonal variability as indicated by a novel closed-cell type photoacoustic spectroscopy (PAS) system. That allowed mathematical modeling of a marine biofilm under steady state, in particular the specific growth rates μi, and the conditioning or induction times λi to be derived from simultaneous multitechnique signals. A set of the established biofilm structural and physical parameters could be modern water body trophic state indexes.

Assessing the trophic state of water bodies by high-resolution remote spectrometry in visible band

Analysis is presented of many-year spectrometric data in the visible band of electromagnetic spectrum collected for the Don R., including the Tsimlyansk Reservoir in 2010–2013 with a period of ~15 days. An algorithm has been proposed for separating spectral brightness coefficient of the rising radiation from water into six categories. A nomenclature scale of the trophic status of water bodies has been constructed. The obtained scale coincides with the nomenclature scales constructed by chlorophyll a concentration for water bodies under different physiographic conditions. The unquestioning advantage of remote sensing methods for assessing water body (WB) trophic status is emphasized, i.e., the possibility to carry out real-time studies within minutes at high representativeness of the results with respect to the examined aquatic ecosystem.

Indices of zooplankton community as valuable tools in assessing the trophic state and water quality of eutrophic lakes: long term study of Lake Võrtsjärv

On the basis of long-term (1964-2011) research, we tested the hypothesis that the zooplankton community has a highly indicative value in assessing the ecosystem and trophic state of water bodies. Basing on the results of our study and taking into account relevant data from numerous zooplankton studies, we can conclude that the zooplankton measures deserving to be used as indicators in the monitoring of Lake Vortsjarv (and other similar eutrophic water bodies) could be the following: i) indicatory species of eutrophic waters [ Anuraeopsis fissa (Gosse), Keratella tecta (Gosse), Trichocerca rousseleti (Voigt), Chydorus sphaericus (O. F. Muller), Bosmina longirostris (O. F. Muller)]; ii) indicatory species of oligo-mesotrophic waters [ Conochilus unicornis Rousselet, Kellicottia longispina (Kellicott), Ploesoma hudsoni (Imhof), Bosmina berolinensis Imhof, Eudiaptomus gracilis (Sars)]; iii) number and diversity of species; iv) mean zooplankter weight, mean cladoceran weight, mean rotifer weight and mean copepod weight; v) rotifer abundance; vi) the share (%) of rotifers in total zooplankton abundance; vii) the ratio of abundance of large cladocerans to abundance of all cladocerans (N LargeClad /N Clad ); viii) the ratio of calanoid copepod abundance to cyclopoid copepod abundance (N Cal /N Cycl ); ix) the ratio of crustacean abundance to rotifer abundance (N Crust /N Rot ). The results of our study show that several zooplankton parameters are among the biological quality elements (BQE) deserving to be included in the Water Frame Directive system.

Evaluation of empirical models coupled with EUTROMOD for water quality prediction in Kansas reservoirs

Agricultural land use contributes high nutrient and sediment loads to nearby streams, lakes, and reservoirs, which can lead to excessive algal growth and increased siltation. Future intensification of agricultural production could further aggravate water quality concerns. To objectively evaluate the effects of agricultural intensification on future water quality, modeling tools must be able to quantitatively predict the degree to which land use change will affect the trophic state of water bodies. This study evaluated the water quality model EUTROMOD as well as several national and regional in-lake empirical water quality models as predictive tools for analyzing and estimating water quality in 28 Kansas reservoirs of varying size and watershed land use. Model-predicted nutrient loading was used with several in-lake empirical models to predict values for total nitrogen (TN), total phosphorus (TP), and chlorophyll a concentrations. Predicted values were then compared to long-term water quality measurements obtained from the Kansas lake and reservoir monitoring program. All models over-predicted concentrations of TN and TP in Kansas reservoirs; however, predictions from the Bachmann TN and Canfield-Bachmann TP in-lake empirical models were most closely coupled to observed trends and had the least error. Two possible sources of model bias were identified: the sedimentation coefficient in the in-lake empirical models and the nutrient loading estimates from the watershed model. Areas of further research are suggested for determining the dominant source of model bias and improving quantitative predictions of water quality in the Midwest, USA.

Characteristics of Phytoplankton Community Structure and Evaluation of Trophic State of Water Body in Bosten Lake

Bosten Lake was the largest inland freshwater lake in China. It is facing with a series of ecological problems nowadays. The phytoplankton and water samples of seventeen sampling sites in Bosten Lake were collected in September 2012. Results show that sixty-four species (genera) of phytoplankton, which belong to six phyla, are identified. The community structure of phytoplankton is dominated by Chlorophyta. The mean cell density of phytoplankton in whole lake is 8179.01×104cells·L-1 and Cyanophyta accounts for 94.71%. The dominant species are Chroococcus sp. and Synedra acus. In terms of Shannon-Wiener diversity index, Margalef richness index, Pielou evenness index and total nitrogen content, it is ascertained that trophic state of water body in Estuary and Pumping Station is between mesotrophication and eutrophication. While in the other districts, the water body is eutrophic. In addition, the eutrophic degree of water body in District IV is higher.

Effect of water-loving bird colonies on zooplankton in littoral zones of water bodies of different types

Changes in zooplankton developing under the effect of waste products from water-loving bird colonies were studied in water bodies of different types. The trophic status index in the nesting area showed no difference from its background values in an oligomesotrophic water body but was decreased in mesoeutrophic and eutrophic-hypertrophic water bodies. The abundance and biomass of zooplankton in the oligomesotrophic and mesoeutrophic water bodies were consistently higher than background values, while in the eutrophichypertrophic water body they were higher only at the beginning and in the middle of the nesting period. Irrespective of the trophic state of water body, the species diversity of zooplankton in the zone of impact from bird colonies was increased, but the number of dominant species remained unchanged, and no mass development of species indicating high organic load was observed; the proportion of Rotifera in the total abundance and biomass of zooplankton was decreased, that of Copepoda was increased, and the abundance of Cladocera was found to increase with the degree of overgrowing. Among possible explanations, this specific response of zooplankton is most likely due to changes in the ratio of nitrogen and phosphorus in the water.

The use of PCR-RFLP to genetically distinguish the morphologically close species: Ceriodaphnia dubia Richard, 1894 and Ceriodaphnia silvestrii Daday, 1902 (Crustacea Cladocera)

The cladocerans are important components of planktonic and benthic freshwater and good indicators of the trophic state of water bodies. The morphological taxonomy of many species of Cladocera is considered complex with minor differences separating some species. Nowadays, molecular techniques provide a powerful tool to identify and classify different taxonomical levels, using mainly ribosomal RNA genes (rRNA) as molecular markers. In the present work we performed PCR-RFLP to separate Ceriodaphnia dubia, an exotic species in Brazil and the native species Ceriodaphnia silvestrii, widely distributed in Brazilian freshwater. The RFLP analysis of the ITS1-5.8S-ITS2 region of rRNA genes showed to be different between C. dubia and C. silvestrii when using enzymes EcoRI, ApaI and SalI. Thus, the ITS1-5.8S-ITS2 region proved to be a useful molecular marker to differentiate the studied Ceriodaphnia species, which makes the task easier of telling apart species that are morphologically very similar. Also, this methodology might be interesting in determining the distribution of the exotic species C. dubia in Brazilian freshwaters, particularly in cases when C. dubia occurs in the absence of C. silvestrii, a particularly difficult task for ecologists who are not taxonomy specialists.

Relating planktonic microbial food web structure in lentic freshwater ecosystems to water quality and land use

Relationships among picoplankton, protozoa, phytoplankton, plant nutrients, lake type, drainage basin morphology and land cover were studied in 45 water bodies in South Island, New Zealand that ranged from large, deep, ultra-oligotrophic lakes to shallow, macrophyte-dominated ponds and swamps. The biomasses of most heterotrophic components of the pelagic microbial food webs were positively related to phytoplankton and features of the drainage basin that enhanced nutrient input, and imply strong resource-driven structuring of pelagic microbial food webs. Prokaryotic picophytoplankton biomass was negatively related to indices of eutrophication, and the picoautotroph contribution to total microbial food web biomass declined with increasing total phosphorus concentration from 16.5% in deep lakes to 70:30 in deep lakes, and indicate the potential importance of microbial food webs in carbon transfer to higher trophic levels in deep, less productive lakes. Strong relationships exist between land use in the catchment and pelagic microbial food web structure and biomass across a wide range in size and trophic state of water bodies in heterogeneous landscapes.

Analysis of Nitrogen, Phosphorus, Organic Matter and Pigments in the Sediments of Fishponds and Their Environmental Significance

通过对鱼塘沉积物中营养盐、有机质及色素在放养前后的测试．对比分析了在人类活动（养殖）的影响下，由于鱼塘水体快速富营养化而引起底质上述指标的变化过程，其中快速沉积环境极有利于沉积色素的保存，具有较好的环境营养状况指示意义，同时有机质、色素和营养盐之间存在着密切的相关关系，这为利用色素方法研究短时间序列环境演变，尤其是在近代人类活动影响下的环境变化提供了一定的依据。;Factors and processes such as intense human activities and rapid eutrophication. controlling the concentrations of organic substances, nutrients and organic pigments in sediments were analyzed before and after fish culturing in four fishponds. Results show that rapid sedimentation rate is more favorable for reservation of pigments that can be a significant indicator for trophic state of water bodies. In the meantime, there are close relations among organic substances, nutrients and organic pigments in sediments. These can be useful in sedimentary environmental explanatioa by way of organic pigments index.