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 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.

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>

DETERMINAÇÃO E AVALIAÇÃO DO ÍNDICE DE ESTADO TRÓFICO (IET) EM RIO URBANO LOCALIZADO NO ESTADO DO CEARÁ, BRASIL

2019 ◽  
Vol 21 (2) ◽  
pp. 730-744
Author(s):  
Francisco Bruno Monte Gomes ◽  
Davis Pereira De Paula
Keyword(s):  
Chlorophyll A ◽  
Total Phosphorus ◽  
Urban Space ◽  
Trophic State ◽  
Trophic State Index ◽  
Sampling Point ◽  
Water Sampling ◽  
State Index ◽  
High Concentrations ◽  
Del Rio

A pesquisa teve como objetivo analisar o índice de estado trófico no rio Acaraú localizado em Sobral-Ceará-Brasil. A metodologia consistiu em revisões bibliográficas, análises de campo, delimitação de cinco pontos amostrais ao longo do trecho fluvial, culminando na coleta de amostras de água e avaliação dos parâmetros de Clorofila “A” e Fósforo Total, no período de março/2015 a março/2016. O trecho do rio Acaraú no espaço urbano de Sobral foi dividido em cinco trechos principais, abrangendo entrada e saída. A Clorofila “A” apresentou uma crescente nas estações PT-3 (40,0 µg/L), PT-4 (32,0 µg/L), nos meses de setembro/15 e PT-5 (12,5 µg/L), para o mês de março/16, os menores resultados foram nas estações PT-1 (6,2 µg/L a 9,0 µg/L), PT-2 (6,7 µg/L a 8,0 µg/L). O Fósforo Total variou entre 0,02 mg/l em agosto/15 na estação PT-1 a 22,5 mg/l em dezembro/15 da estação de coleta PT-5. O cálculo do IET (Índice de Estado Trófico) se mostrou com nível de predominância no grau mesotrófico nos pontos PT-1, PT-3 e PT-5, entre agosto/15 a dezembro/15. O grau hipereutrófico foi resultado nos pontos PT-3, PT-4 e PT-5, afetados significativamente pelas elevadas concentrações de matéria orgânica e nutrientes. Portanto, conclui-se que as águas no rio Acaraú apresentaram vulnerabilidades aos processos de eutrofização, se fazendo necessária a implantação de um planejamento urbano eficiente.Palavras-chave: Eutrofização; Poluição hídrica; Qualidade de água; Rio urbano. ABSTRACTThe aim of this research was analyze the trophic state index in the Acaraú river located in Sobral-Ceará-Brazil. The methodology consisted of bibliographic reviews, field recognition, delimitation of five sampling points along the river, culminating in the water sampling and evaluation of the parameters of Chlorophyll "A" and Total Phosphorus, from March/2015 to March/2016. The section of the Acaraú River in the urban space of Sobral was divided into five main sections, including entrance and exit. Chlorophyll "A" increased in PT-3 (40.0 μg/L), PT-4 (32.0 μg/L) in September/15 and PT-5 (12.5 μg/L), for the month of  March/16, the lowest results were in PT-1 (6.2 μg/L at 9.0 μg/L), PT-2 (6.7 μg/L at 8.0 μg/L). Total Phosphorus ranged from 0.02 mg/L to 22.5 mg/L (August/15– December/15) at the PT-5 sampling point. The TSI (Trophic State Index) showed that there was predominance on mesotrophic degree at points PT-1, PT-3 and PT-5among August/15 and December/15. The hypereutrophic degree that was found in points PT-3, PT-4 and PT-5, were the results of a significant influence by high concentrations of organic matter and nutrients. Therefore, it is concluded that the waters in Acaraú River presents vulnerabilities to the eutrophication processes, and it is necessary to implement efficient urban planning.Keywords: Eutrophication; Water pollution; Water quality; Urban river. RESUMENLa investigación tuvo como objetivo analizar el índice de estado trófico en el río Acaraú ubicado en Sobral-Ceará-Brasil. La metodología consistió en revisiones bibliográficas, análisis de campo, delimitación de cinco puntos de muestreo a lo largo de la sección del río, que culminó con la recolección de muestras de agua y la evaluación de los parámetros de Clorofila "A" y Fósforo Total, de marzo/2015 a marzo/2016. El tramo del río Acaraú en el espacio urbano de Sobral se dividió en cinco tramos principales, que incluyen la entrada y la salida. La clorofila “A” presentó un crecimiento en las estaciones PT-3 (40.0 µg/L), PT-4 (32.0 µg/L) en septiembre/15 y PT-5 (12.5 µg/L). L), para el mes de marzo/16, los resultados más bajos fueron en PT-1 (6.2 µg/L a 9.0 µg/L), PT-2 (6.7 µg/L a 8.0 µg/L). El fósforo total varió de 0.02 mg/l en agosto/15 en la estación PT-1 a 22.5 mg/l en diciembre/15 desde la estación de recolección PT-5. El cálculo del EIT (Índice de estado trófico) fue predominantemente mesotrófico en PT-1, PT-3 y PT-5, del 15 de agosto al 15 de diciembre. El grado hipereutrófico se obtuvo en los puntos PT-3, PT-4 y PT-5, significativamente afectados por las altas concentraciones de materia orgánica y nutrientes. Por lo tanto, se concluye que las aguas del río Acaraú presentan vulnerabilidades a los procesos de eutrofización, lo que hace necesaria la implementación de una planificación urbana eficiente.Palabras clave: Eutrofización; Contaminación del agua; Calidad del agua; Río urbano.

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 MONITORAMENTO DA AQUICULTURA EM RESERVATÓRIOS CONTINENTAIS POR MEIO DO ÍNDICE DE ESTADO TRÓFICO

Nativa ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 262
Author(s):  
Clauber Rosanova ◽  
Emílio Sousa Pinho ◽  
Flávia Tavares Matos ◽  
Alberto Akama ◽  
Guilherme Wolff Bueno ◽  
...  
Keyword(s):  
Trophic State ◽  
Anthropogenic Activities ◽  
Quality Parameters ◽  
Trophic State Index ◽  
Time Data ◽  
Oxygen Conductivity ◽  
State Index ◽  
And Control ◽  
Status Index

A aquicultura é a atividade que mais cresce dentre os setores de produção de alimentos, porém, sua prática pode causar impactos ambientais no ambiente aquático, caso não haja um plano de monitoramento eficiente. O objetivo do presente trabalho foi avaliar o grau de trofia do ambiente utilizando o Índice de Estado Trófico (IET) em uma atividade aquícola de sistema de produção em tanques-rede no reservatório do Lajeado, Palmas, Tocantins na estação seca do ano. O monitoramento foi realizado no período de maio/2017 a agosto/2017 e envolveu a coleta de amostras para análises dos seguintes parâmetros de qualidade de água: fósforo total e clorofila-a. Paralelamente, houve a realização de coleta de dados de temperatura, turbidez, oxigênio dissolvido, condutividade, pH e sólidos totais dissolvidos. Os resultados do cálculo do Índice de Estado Trófico (IET) mostraram que a área em estudo durante os meses de maio e agosto apresentou-se predominantemente em graus eutrófico e hipereutrófico. O ponto controle também apresentou alto grau de trofia, indicando que o estado trófico do lago nas proximidades da área aquícola sofre forte influência de atividades antrópicas externas. Assim, os efeitos desta atividade a médio e longo prazo são difíceis de serem previstos, havendo a necessidade constante do monitoramento e controle da qualidade da água.Palavras-chave: aquicultura, eutrofização, impacto ambiental, poluição, tanque rede. MONITORING OF AQUACULTURE IN CONTINENTAL RESERVOIRS USING THE TROPHIC STATUS INDEX ABSTRACT:Aquaculture is the fastest growing activity among food production sectors, however, its practice can cause environmental impacts, in case if a monitoring plan is not applied. The objective of the present study was to evaluate the trophic environment status using the Trophic State Index (TSI) in an aquaculture activity in a netcage system in the Lajeado reservoir, Palmas, Tocantins during the dry season. The monitoring was carried out from May / 2017 to August / 2017 and involved the water sampling for analysis of the following water quality parameters: total phosphorus and chlorophyll-a. At the same time, data were collected on temperature, turbidity, dissolved oxygen, conductivity, pH and total dissolved solids. The Trophic State Index (TSI) results showed that the area under study during the months of May and August was predominantly under a supereutrophic condition. It indicates that the lake trophic state in the aquaculture surrounding area is strongly influenced by external anthropogenic activities. Thus, the effects of this activity in the medium and long term are difficult to predict, so it´s necessary to monitor and control the water quality.Keywords: aquaculture, eutrophication, environmental impact, pollution, net cage.

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 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.

scholarly journals External Nutrient Load and Determination of the Trophic Status of Lake Ziway

2018 ◽  
Vol 3 (2) ◽  
pp. 1-16 ◽  
Author(s):  
Dessie Tibebe ◽  
Feleke Zewge Beshah ◽  
Brook Lemma ◽  
Yezbie Kassa ◽  
Ashok N. Bhaskarwar
Keyword(s):  
Chlorophyll A ◽  
Trophic State ◽  
Trophic Status ◽  
Trophic State Index ◽  
Nutrient Load ◽  
Nutrient Loads ◽  
Mean Values ◽  
State Index ◽  
The Mean ◽  
External Nutrient

Lake Ziway is shallow freshwater located in Northern part of Ethiopian Rift Valley. Expansions of the flower industry, fisheries, intensive agricultural activities, fast population growth lead to deterioration of water quality and depletion of aquatic biota. The objectives of the present study are to evaluate the spatial and temporal variations in the external nutrient load and determine the trophic status of Lake Ziway in 2014 and 2015. The nutrients and Chlorophyll-a were measured according to the standard procedures outlined in APHA, 1999. From the result Ketar and Meki Rivers catchment showed the major sources of external nutrient loads to the lake ecosystem. The mean external soluble reactive phosphorus (SRP), total phosphorus (TP), total inorganic nitrogen (TIN) and total nitrogen (TN) loads to Lake Ziway were 230, 2772, 4925 and 24016 kg day-1, respectively. A general trend which was expected that the nutrient loads would be much higher in rainy season than in dry season. The mean concentrations of trophic state variables for TN, TP and Chla were 6700, 212 and 42 mg L-1, respectively. The mean values of TSI-TP, TSI-Chl-a, TSI-TN and TSI-SD were 79, 66, 81 and 83, respectively and the overall evaluation of Carlson Trophic State Index (CTSI) of Lake Ziway was 77. Therefore, the lake is under eutrophic condition. The mean values of TN: TP ratio was 48 which were very high. The trophic state index determined with chlorophyll-a showed lower value than those determined with all trophic state indices values of TN, TP, and SD which indicated that non-algal turbidity affected light attenuation for algal growth. This suggested that phosphorus was the limiting nutrient in Lake Ziway. Due to its importance as being the lake is an intensive agricultural site, management solutions must be urgently developed in order to avoid the destruction of the lake.

scholarly journals Variation of Chironomidae (Insecta: Diptera) trophic guilds and their relation with trophic state in reservoirs in the semiarid

2020 ◽  
Vol 42 ◽  
pp. e43
Author(s):  
Valéria Dos Santos Pereira ◽  
Daniele Jovem Azevêdo ◽  
Evaldo De Lira Azevêdo ◽  
Joseline Molozzi
Keyword(s):  
Littoral Zone ◽  
Trophic State ◽  
Trophic Status ◽  
Trophic State Index ◽  
Trophic Guilds ◽  
Trophic Groups ◽  
Sensitive Species ◽  
Potential Capacity ◽  
State Index ◽  
Status Index

The Chironomidae larvae are sensitive to variations in aquatic ecosystem conditions. We aim to analyze the variation of Chironomidae trophic guilds and their relation to the trophic state index in reservoirs in the semiarid. The study was conducted from 66 sites, distributed in the littoral zone of three reservoirs of Piranhas-Assu river, during June and December of 2014. The larvae were collected, and after identification, were classified in functional trophic groups. We applied the Trophic Status Index of Carlson, modified by Toledo for trophic classification. Sabugí reservoir was the only classified as mesotrophic (52,60±3,64) in June, where the greatest levels of diversity also occurred in the trophic guilds: gatherer-gollector (9 genera), predator (6 genera) and filterer-collector (1 genus). Higher levels of eutrophication occurred in Passagem das Traíras reservoir (84,99±6,19), the same with the smallest diversity in the guilds: gatherer-collector (3 genera) and 1 genus in the other categories. The variation of trophic guilds has been associated with trophy levels, because higher levels of degradation eliminate sensitive species, reducing the number of taxa. Thus, the Chironomidae trophic guilds demonstrate potential capacity for indicating the degree of impact to which the reservoirs are submitted.

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