Population dynamics and management of two cichlid species in the Shatt Al-Arab River, Iraq

Cichlids are invasive fish to Iraqi waters and became well established and prevailing in different waters. Despite that, there is no stock assessment study conducted for these fish. So, growth, mortality, recruitment and yield-per-recruit of two cichlid’s species; Coptodon zillii and Oreochromis aureus from the Shatt Al-Arab River, Iraq were evaluated from November 2015 to October 2016 using the FiSAT software. A total of 1285 C. zillii (2.9-24.0 cm TL) and 1353 O. aureus (4.5-25.0 cm TL) were examined. Length-weight relationships were derived, indicating allometric growth for both species. The growth parameters (L?, K, Rn, to and ?) obtained for C. zillii were 25.5 cm, 0.320, 0.212, -0.793 and 2.318, respectively, while for O. aureus were 27.8, 0.490, 0.214, -0.271 and 2.578, respectively. The annual rate of total mortality (Z), fishing (F) and natural (M) for C. zillii was found to be 1.51, 0.84 and 0.68 respectively, and for O. aureus 2.49, 1.08 and 1.41, respectively. The present exploitation rates (Epresent) for C. zillii and O. aureus were computed to be 0.454 and 0.57, respectively. Lengths at first capture (LC) were 12.97 cm for C. zillii and 13.25 cm for O. aureus. The peaks of recruitment of C. zillii and O. aureus were from February to May and May to July, respectively. The Epresent for C. zillii and O. aureus were below the biological target reference points (F0.1  and Fmax), indicating that these species were not overexploited. For management purposes, more yields could be obtained by an increase in the fishing activities on cichlids

Population dynamics of an invasive species Carassius auratus in the Shatt Al-Arab River, Iraq

The population dynamics of the crucian carp, Carassius auratus in the Shatt Al-Arab River, Iraq was studied from November 2015 to October 2016 with monthly samples collected by different fishing gears. The FAO-ICLARM Stock Assessment Tool (FiSAT II) software was used for the mathematical analysis. Length-weight relationship was calculated as W= 0.0149L3.065 for fish length 4.6 to 26.8 cm. Growth parameters L∞, K and Ø were computed as 29.1 cm, 0.51 and 2.635. The total (Z), natural (M) and fishing (F) mortalities were 2.69, 1.09 and 1.60, respectively. Exploitation rate (E) was 0.59. Length at first capture (Lc) was found to be 10.04 cm. C. auratus displayed one main pulse of annual recruitment. The relative yield per recruit analysis revealed that the exploitation rate (E) of C. auratus was higher than the biological target reference points E0.1 and equivalent to Emax. It could be concluded that the C. auratus stock in the Shatt Al-Arab River is operating nearby the exploited situation and needs some precautionary measures to avoid the overexploitation by activating the national law of fishing, exploiting and protecting aquatic resources, in particular preventing illegal fishing methods and follow up the execution of the closed season to prevent the decline of our fish resources

Evaluation of the inland fisheries in Basrah province in Iraq during 2020-2021

The study was aimed to update the knowledge on the fish landings of the inland fisheries in Basrah province, Iraq. The species composition, species and total landings, and their trends in six landing sites throughout the study region were evaluated during the year 2020-2021. Species compositions were included seven cyprinids’ species, three cichlids’ species, three mullet’s species, and two species from sparids and silurids. The exotic species, C. carpio, tilapias species and C. auratus dominated the landings constituting 44.2% of the total catch, whereas the highly valued native species (M. sharpeyi, L. xanthopterus, C. luteus and A. grypus) forming only 12.4% of the total catch. The total landing reached 2,427.78 t in 2020 and 2,365.15 t in 2021, and these values were higher than what was recorded during the past years since the year 2009. This is due to the prevalence of aliened species and the increase in the fishing effort, such as the numbers of fishermen and fishing boats. Therefore, in fisheries management point of view, it is essential to enhance the stocks of the native species, minimize the dispersal and impacts of some exotic species, and activate the national regulating fishing, exploitation and protection of aquatic organisms to improve the inland fisheries

Larson Miller Parameter for the Prediction of the Creep Life of Unweld and Welded P91 Steel

For structural components that operate at elevated temperatures, martensitic P91 steel is preferable. It is widely used in steam generators in the fossil-fired thermal and nuclear power generation sectors due to its creep endurance and corrosion resistance. Several creep laws, such as Monkman-Grant, Theta project, Wilshire and Sinh model, Omega technique, and the Larson Miller Parameter (LMP),   have been developed over time to predict and failure of materials susceptible to the creep phenomenon. However, only the Omega Law and Larson-Miller Parameter are the only two methods approved in API 579-1. In this work, the creep test for welded and unwelded P91were conducted at temperatures of 600°C under stresses of 165, 175 MPa, and 190 MPa. In comparison to the welded specimens, the unwelded specimens displayed a continuously more substantial development of creep strain with time, resulting in a higher steady-state creep rate and a shorter rupture life. The increased magnitude of creep-rupture data has been observed to impact the dependability of creep life. Because of more significant changes in service temperature and stress conditions, the dependability of P91 steel has deteriorated, as well as an increase in creep life. The rupture life has been predicted using the LMP method, which utilizes the constant C parameter. At the same stress, the predicted creep life for weld material shows a higher value than that of the parent material, which is consistent with the experimental result

Larson Miller Parameter for the Prediction of the Creep Life of Unweld and Welded P91 Steel

For structural components that operate at elevated temperatures, martensitic P91 steel is preferable. It is widely used in steam generators in the fossil-fired thermal and nuclear power generation sectors due to its creep endurance and corrosion resistance. Several creep laws, such as Monkman-Grant, Theta project, Wilshire and Sinh model, Omega technique, and the Larson Miller Parameter (LMP),   have been developed over time to predict and failure of materials susceptible to the creep phenomenon. However, only the Omega Law and Larson-Miller Parameter are the only two methods approved in API 579-1. In this work, the creep test for welded and unwelded P91were conducted at temperatures of 600°C under stresses of 165, 175 MPa, and 190 MPa. In comparison to the welded specimens, the unwelded specimens displayed a continuously more substantial development of creep strain with time, resulting in a higher steady-state creep rate and a shorter rupture life. The increased magnitude of creep-rupture data has been observed to impact the dependability of creep life. Because of more significant changes in service temperature and stress conditions, the dependability of P91 steel has deteriorated, as well as an increase in creep life. The rupture life has been predicted using the LMP method, which utilizes the constant C parameter. At the same stress, the predicted creep life for weld material shows a higher value than that of the parent material, which is consistent with the experimental result

Efektifitas Beauveria Bassiana Vuill Terhadap Pengendalian Spodoptera Exigua Hubner (Lepidoptera : Noctuidae) Pada Tanaman Bawang Merah Lokal Palu (Allium Wakegi)

The purpose of this study is to determine the effectiveness of Beauveria bassiana on the control of Spodoptera exigua Hubner ( Lepidoptera : Noctuidae ) on shallot crop varieties Palu valley ( Allium wakegi ) . This research was conducted in the village of Sidera , District Biromaru , Sigi and in the Laboratory of Plant Pests and Diseases ( HPT ) .The research was conducted from April to June 2014. This study was prepared by Group Random Design ( RAK ) with patterns of factorial , consisting of 2 factors with 3 replications , in order to obtain 24 units experiment , with treatments as follows : F1 namely doses : D0 : Without the application of Beauveria bassiana / use distilled water , D1 : 6 grams B.bassiana / L of water , D2 : 8 gr B.bassiana / L of water , D3 : 10 gr B.bassiana / L of water and F2 is the time interval applications with 2 levels : W1 : interval of 5 days and W2 : interval of 7 days . The data were analyzed using analysis of variance ( ANOVA ) and if it shows a marked influence further tested using the Test HSD 5 % . Based on observations indicate that the fungus application B.bassiana significantly affect the intensity of the attacks S.exigua , during the observation time 4,5,6,7 and 8 MST show that the intensity of the treatment D3W1 provide S.exigua the lowest compared to all other treatments at an all-time observation . In observation of 4 MST intensity of the attack only reached 2.02% , on the observation 5MST reached 1.74% , at 6MST 7MST 1.39 % and 1.19 % . In observation of severe crop production ( Table 2 ) showed that the treatment D3W1 (10g / L , 5H ) produced the highest plant weight 143,82g / clump converted can reach 3.60 t / ha-1

Effect of Gliricidia sepium leaves and molases inclusion on aerobic stability, value and digestibility of Napier grass silage

Most tropical roughage feeds are generally deficient in nitrogen, energy or some minerals and vitamins. A study was conducted to evaluate the effect of adding Gliricidia (Gliricidia sepium) leaves and molasses to Napier grass (Pennisetum purpureum) silage. Silage were prepared from Napier grass and mixed with Gliricidia and molasses. There were four treatments involved which were NG, containing Napier grass only which was the experiment control, GS containing Napier grass mixed with 5% Gliricidia leaves, ML containing the Napier grass mixed with 5% molasses, and MG containing Napier grass mixed with 5% molasses and 5% Gliricidia leaves. The treatments were analyzed for aerobic stability, dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), and digestibility. There were no significant differences in aerobic stability of silage between treatments, and the treatments with Gliricidia were higher in crude protein (p<0.05) and had better digestibility (p<0.05) when compared to the control. In conclusion, Gliricidia leaves as additives to Napier grass silage can improve its nutritive value and quality

Assessing students’ abilities in interpreting the correlation and regression analysis

A case study was carried out on students who were being exposed to some theoretical concepts of the correlation and regression topics to investigate their ability to compute and interpret the Pearson’s correlation coefficient and the slope of regression. The findings revealed that a low percentage of students (19.43%) successfully completed their interpretation of correlation coefficient and 33.18% of the students managed to interpret the computed value of regression slope completely. It was also found that the students’ ability to interpret regression slope was significantly associated with the ability to interpret the correlation coefficient correctly. It is hoped that the findings obtained from this study will shed some light on improving teaching practices of statistics educators so as to help students in gaining better understanding on interpreting the correlation and regression analysis.Keywords: correlation; Pearson; regression; coefficients; interpretation; students’ abilit

Kemampuan Memahami Unsur Intrinsik Teks Drama Siswa Kelas VIII Mts Muhammadiyah Desa Penyasawan Kecamatan Kampar

The purposes of this research is to describe the ability in comprehend the element of intrinsic in drama of second year student at MTs Muhammadiyah Penyasawan village Kampar district. The element of intrinsic is element which develop build belleslettres from within. The element of intrinsic is an important elemen whick is supposed to be learned by students in learning literature. In learned literature at school, comprehend the element of intrinsic in drama is one of basic component that should be learned at second grade of MTs. This research is aimed to know the students\u27 ability in comprehend the element of intrinsic in drama of second year student at MTs Muhammadiyah Penyasawan village Kampar district. Generally, there are 5 element of intrinsic are those theme, plot, characteristic, setting, and moral message. In this research, the method that\u27s used is descriptive method with 50 samples. To collect the data, the researcher collected the students\u27 test result, gave score, found the percentage of each element, and considered the average score. The resul can be concluded that the students\u27 ability in understanding the element of intrinsic in drama of second year students at MTs Muhammadiyah Penyasawan village Kampar district are categorized as low with average score 67. Percentage of high ability level student was 8%, medium 32%, and low 60%. The detail of average score of intrinsic element that has obtained is that: theme was categorized as low (46), plot was categorized as high (94), characteristic was categorized as low (66), setting was categorized as medium (79), moral message was categorized as low (50)

Kemampuan Memparafrasakan Puisi Kerendahan Hati Karya Taufik Ismail ke Eksposisi Siswa Kelas X Man 039 Tembilahan

This study investigated the ability of paraphrase a poem by Taufik Ismail humility to exposition class X MAN 039 Tembilahan. The aim of this study was to obtain data on the ability of paraphrase a poem by Taufik Ismail humility to exposition class X MAN 039 Tembilahan. The ability of paraphrase of the aspects of understanding the content and paraphrased. This study is a quantitative-descriptive. This research data is data test capabilities humility paraphrase a poem by Taufik Ismail to exposition class X MAN 039 Tembilahan. Instruments in this research is a form of poetry texts given to members of the sample. The data collection was done by using the test. The population in this study were 301 students with a total sample of 168 students. Data were analyzed with descriptive methods. The validity of the data obtained through data validation. Research results seen from the test results the ability of paraphrase a poem by Taufik Ismail humility to exposition class X MAN 039 Tembilahan. Seen from the aspect of understanding the content obtained average value amounted to 70.07 with a low category. Then, from the aspect paraphrase obtained average value amounted to 73.96 with the medium category