Climate and Hydrological Factors Affecting Variation in Chlorophyll Concentration and Water Clarity in the Bahia Almirante, Panama

2012 ◽  
pp. 323-334
Author(s):  
Rachel Collin ◽  
Luis D'Croz ◽  
Plinio Gondola ◽  
Juan B. Del Rosario
Keyword(s):  
Wind Speed ◽  
Chlorophyll A ◽  
Phytoplankton Biomass ◽  
Nutrient Loading ◽  
Rapid Development ◽  
Chlorophyll Concentration ◽  
Water Clarity ◽  
Annual Rainfall ◽  
Bocas Del Toro ◽  
Factors Affecting

Water clarity and productivity are fundamentally important for the distribution of tropical marine organisms. In the Caribbean, changes in nutrient loading that result from rapid development are thought to have caused increased planktonic productivity, reduced water clarity, and reduced reef and seagrass health. Here we analyze chlorophyll a concentration and water clarity from eight years of environmental monitoring in Bocas del Toro, Panama. Chlorophyll a concentrations did not vary significantly among the six sampled sites and showed no significant temporal changes, despite the recent rapid development in the region, accompanied by scant wastewater treatment. In contrast, water clarity increased significantly during the study period. Because chlorophyll a does not vary closely with water clarity, Secchi depths are likely to reflect changes in suspended particulate matter rather than in phytoplankton biomass. Secchi depths decreased with rainfall and wind speed but increased with solar radiation, supporting the idea that clarity was not tightly linked to phytoplankton biomass. The decrease in annual rainfall, but not wind speed, over the past eight years suggests that the long-term trend in Secchi readings is the result of changes in rainfall patterns.

Cladoceran body length and Secchi disk transparency in northeastern U.S. lakes

2003 ◽  
Vol 60 (12) ◽  
pp. 1477-1486 ◽  
Author(s):  
Richard S Stemberger ◽  
Eric K Miller
Keyword(s):  
Chlorophyll A ◽  
Body Length ◽  
Nutrient Loading ◽  
Size Structure ◽  
Light Attenuation ◽  
Water Clarity ◽  
Secchi Disk ◽  
Particulate Carbon ◽  
Secchi Disk Transparency ◽  
Organic Particles

Mean cladoceran body length of 59 northeastern U.S. lakes was estimated from functional groups that broadly define taxonomic, body size, and grazing potential. Multiple regression of body length, color, and chlorophyll a or total phosphorus against Secchi disk transparency explained 72% and 83% of the variation across lakes, respectively. Analysis that included body length, color, and particulate carbon, a proxy for light backscattering and absorption by suspended organic particles, explained 85% of the variance in transparency. Body length was as important a predictor of water clarity as chemical factors. Furthermore, body length was significantly correlated to temporal variation in transparency within lakes. Because cladocerans primarily filter organic particles in size ranges having high light attenuation efficiencies, body length was consistently more strongly correlated to transparency than to chlorophyll a. Monitoring cladoceran body length should help to distinguish changes in lake transparency due to nutrient loading from changes that reflect fish population size structure and predation intensity on zooplankton. This simple size index can greatly increase the interpretative value of Secchi transparency observations to lake managers.

scholarly journals Decline in Phytoplankton Biomass along Indian Coastal Waters due to COVID-19 Lockdown

2020 ◽  
Vol 12 (16) ◽  
pp. 2584 ◽  
Author(s):  
Deepak R. Mishra ◽  
Abhishek Kumar ◽  
Pradipta R. Muduli ◽  
Sk. Md. Equeenuddin ◽  
Gurdeep Rastogi ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Coastal Waters ◽  
Phytoplankton Biomass ◽  
Nutrient Loading ◽  
Early Stage ◽  
Indirect Evidence ◽  
Urban Centers ◽  
Ecosystem Responses ◽  
Business As Usual ◽  
The Relationship

The SARS-CoV-2 (or COVID-19) lockdown in India, which started at an early stage of its infection curve, has been one of the strictest in the world. Air quality has improved in all urban centers in India, a major emitter of greenhouse gases (GHG). This study is based on the hypothesis that an abrupt halt in all urban activities resulted in a massive decline in NO2 emissions and has also altered coastal nitrogen (N) inputs; in-turn, this affected the trophic status of coastal waters across the country. We present the first evidence of an overall decline in pre-monsoon chlorophyll-a, a proxy for phytoplankton biomass, in coastal waters off urban centers during the peak of the lockdown in April. The preliminary field data and indirect evidence suggests the reduction in coastal chlorophyll-a could be linked to a net decline in nutrient loading, particularly of bioavailable N through watershed fluxes and atmospheric deposition. The preliminary results stress the importance of a further understanding of the relationship between fluctuations in anthropogenic N, due to lockdown measures and coastal ecosystem responses, as countries open-up to a business-as-usual scenario.

scholarly journals Prediction of Algal Chlorophyll-a and Water Clarity in Monsoon-Region Reservoir Using Machine Learning Approaches

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 30 ◽  
Author(s):  
Md Mamun ◽  
Jung-Jae Kim ◽  
Md Ashad Alam ◽  
Kwang-Guk An
Keyword(s):  
Chlorophyll A ◽  
Trophic State ◽  
Secchi Depth ◽  
Water Clarity ◽  
Coefficient Of Determination ◽  
Annual Rainfall ◽  
Support Vector ◽  
Chl A ◽  
Svm Model ◽  
Ann Models

The prediction of algal chlorophyll-a and water clarity in lentic ecosystems is a hot issue due to rapid deteriorations of drinking water quality and eutrophication processes. Our key objectives of the study were to predict long-term algal chlorophyll-a and transparency (water clarity), measured as Secchi depth, in spatially heterogeneous and temporally dynamic reservoirs largely influenced by the Asian monsoon during 2000–2017 and then determine the reservoir trophic state using a multiple linear regression (MLR), support vector machine (SVM) and artificial neural network (ANN). We tested the models to analyze the spatial patterns of the riverine zone (Rz), transitional zone (Tz) and lacustrine zone (Lz) and temporal variations of premonsoon, monsoon and postmonsoon. Monthly physicochemical parameters and precipitation data (2000–2017) were used to build up the models of MLR, SVM and ANN and then were confirmed by cross-validation processes. The model of SVM showed better predictive performance than the models of MLR and ANN, in both before validation and after validation. Values of root mean square error (RMSE) and mean absolute error (MAE) were lower in the SVM model, compared to the models of MLR and ANN, indicating that the SVM model has better performance than the MLR and ANN models. The coefficient of determination was higher in the SVM model, compared to the MLR and ANN models. The mean and maximum total suspended solids (TSS), nutrients (total nitrogen (TN) and total phosphorus (TP)), water temperature (WT), conductivity and algal chlorophyll (CHL-a) were in higher concentrations in the riverine zone compared to transitional and lacustrine zone due to surface run-off from the watershed. During the premonsoon and postmonsoon, the average annual rainfall was 59.50 mm and 54.73 mm whereas it was 236.66 mm during the monsoon period. From 2013 to 2017, the trophic state of the reservoir on the basis of CHL-a and SD was from mesotrophic to oligotrophic. Analysis of the importance of input variables indicated that WT, TP, TSS, TN, NP ratios and the rainfall influenced the chlorophyll-a and transparency directly in the reservoir. These findings of the algal chlorophyll-a predictions and Secchi depth may provide key clues for better management strategy in the reservoir.

scholarly journals Analisis Sebaran Klorofil-A dan Suhu Permukaan Laut sebagai Fishing Ground Potensial (Ikan Pelagis Kecil) di Perairan Kendal, Jawa Tengah

2018 ◽  
Vol 7 (2) ◽  
pp. 67
Author(s):  
Andita Agung ◽  
Muhammad Zainuri ◽  
Anindya Wirasatriya ◽  
Lilik Maslukah ◽  
Petrus Subardjo ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Chlorophyll A ◽  
Rapid Development ◽  
Chlorophyll Concentration ◽  
Pelagic Fish ◽  
Sea Surface ◽  
Fishing Ground ◽  
Purposive Sampling ◽  
Central Java

Perairan Kendal merupakan salah satu kabupaten di Jawa Tengah dengan luas wilayah ± 1.002,23  dan mengalami perkembangan pesat terutama di bidang perikanan. Perairan Kendal adalah salah satu wilayah penyebaran ikan demersal dan pelagis yang cukup potensial di perairan Utara Jawa Tengah. Tujuan penelitian ini untuk memprediksi zonasi fishing ground ikan pelagis  kecil di Perairan Kendal berdasarkan parameter klorofil-a dan suhu permukaan laut. Penelitian ini menggunakan metode kuantitatif, penentuan lokasi pengambilan sampel menggunakan metode purposive sampling. Berdasarkan hasil penelitian diketahui bahwa perairan Kendal memiliki nilai konsentrasi klorofil-a berkisar antara 0.34 – 4.86 mg/  konsentrasi tertinggi di Timur Laut muara sungai Bodri dan di ikuti dengan hasil tangkapan ikan paling banyak yaitu 53 kg. Konsentrasi suhu permukaan laut berkisar 30,5 - 31ᵒC. Perbedaan nilai konsentrasi klorofil-a dan suhu permukaan laut dipengaruhi oleh angin yang berhembus di perairan sehingga diduga mengakibatkan terjadinya proses mixing.  Analysis of Chlorophyll-A Distribution and Potential Sea Surface As Fishing Ground Temperature in Kendal Coastal, Central JavaThe waters of Kendal is one district in Central Java with an area of ± 1.002.23  and experienced rapid development, especially in the field of fisheries. The waters of Kendal is one of the potential demersal and pelagic fish distribution areas in the waters of North Central Java. The purpose of this study was to predict the potential fishing ground of small pelagic fish in Kendal Waters based on the parameters of chlorophyll-a and sea surface temperature. This research uses quantitative method while determining the location of sampling using purposive sampling method. Based on the research results it can be seen that the waters of Kendal has a value of chlorophyll-a concentration ranging from 0.34 - 4.86 mg/   with the highest concentration that is in the Northeast estuary Bodri river and followed by the catch of most fish that is 53 kg. Concentrations of sea surface temperature range from 30.5 - 31ᵒC. Differences in the value of a-chlorophyll concentration and sea-surface temperatures across the waters are influenced by winds that blow in the waters resulting in a mixing process. 

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

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

<p align="center"><strong>ABSTRAK</strong></p><p class="abstrak">Waduk 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 <em>Trophic State Index</em> (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 (R<sup>2</sup>) tertinggi. Hasil penelitian merepresentasikan bahwa nilai R<sup>2</sup> kejernihan air sebesar 0,813, total fosfor sebesar 0,268, dan klorofil-a sebesar 0,584. Apabila nilai R<sup>2 </sup>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.</p><p><strong>Kata kunci: </strong>Waduk Gajah Mungkur, citra Landsat 8 OLI, regresi, TSI, status trofik</p><p class="judulABS"><strong>ABSTRACT</strong></p><p class="Abstrakeng">Gajah 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 (R<sup>2</sup>). The results represented that R<sup>2</sup> of water clarity is 0.813, total phosphorus is 0.268, and chlorophyll-a is 0.584. If R<sup>2</sup> 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.</p><p><strong><em>Keywords: </em></strong><em>Gajah Mungkur Reservoir, </em><em>L</em><em>andsat 8 OLI satellite imagery, regression, TSI, trophic state</em></p>

THE NATIONAL SECURITY SYSTEM

2018 ◽  
Vol 28 (6) ◽  
pp. 1849-1854
Author(s):  
Marin Petkov
Keyword(s):  
National Security ◽  
Functional State ◽  
Rapid Development ◽  
Science And Technology ◽  
Security System ◽  
Scientific Article ◽  
Moral Code ◽  
Internal Factors ◽  
Factors Affecting

The rapid development of science and technology has led to the emergence of a crisis in society. Science "pushes" religion, but does not offer a new moral code in its place. The definitions of "security" are almost as many and as controversial as postmodernism. For the purposes of this study, however, it will be sufficient to define security as "the functional state of a system that provides for the neutralization and counteraction of external and internal factors affecting or potentially damaging the system." This scientific article presents a study, which seeks to answer the question why the paradigm "security" is so important in the postmodern society, what are the roots of its influence and meaning, and to seek conclusions and guidelines for its increase.

Solid Waste Management on Romanian Households

2018 ◽  
Vol 68 (12) ◽  
pp. 2941-2947
Author(s):  
George Ungureanu ◽  
Gabriela Ignat ◽  
elena Leonte ◽  
Carmen Luiza Costuleanu ◽  
Nicoleta Stanciu ◽  
...  
Keyword(s):  
Waste Management ◽  
Solid Waste ◽  
Agricultural Development ◽  
Management Practices ◽  
Solid Waste Management ◽  
Raw Materials ◽  
Rapid Development ◽  
Disposal Site ◽  
Solid Waste Disposal ◽  
Factors Affecting

The problem associated with the household behavior on solid waste disposal site in today�s society is complex because of the large quantity and diverse nature of the wastes. Due increase the population, rapid development, global agricultural development has moved rapidly, limitations of financing, emerging limitations of both energy and raw materials and also add to the complexity of any waste management system, large quantities of wastes are being generated in different forms such as solid, liquid and gases. This research explored factors affecting the level of participation in solid waste segregation and recycling of households in Romania, as well as examining current Romania households waste management practices and their knowledge of waste management. This study investigated the solid waste situation and the organization of solid waste management in both urban and rural settings from the perspective of households. Solid waste management is a key component of public services which needs to serve the urban and rural municipalities in an efficient way in order to maintain a decent standard of public health.

In Vivo Fluorescence of Chlorophyll A: Estimation of Phytoplankton Biomass and Activity in Římov Reservoir (Czech Republic)

1993 ◽  
Vol 28 (6) ◽  
pp. 29-33 ◽  
Author(s):  
V. Vyhnálek ◽  
Z. Fišar ◽  
A. Fišarová ◽  
J. Komárková
Keyword(s):  
Czech Republic ◽  
Chlorophyll Fluorescence ◽  
Primary Production ◽  
Chlorophyll A ◽  
Phytoplankton Biomass ◽  
In Vivo Fluorescence ◽  
Fluorescence Of Chlorophyll A ◽  
Římov Reservoir ◽  
Natural Phytoplankton

The in vivo fluorescence of chlorophyll a was measured in samples of natural phytoplankton taken from the Římov Reservoir (Czech Republic) during the years 1987 and 1988. The fluorescence intensities of samples either with or without addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron, DCMU) were found reliable for calculating the concentration of chlorophyll a during periods when cyanobacteria were not abundant. The correction for background non-chlorophyll fluorescence appeared to be essential. No distinct correlation between a DCMU-induced increase of the fluorescence and primary production of phytoplankton was found.

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