Respon Kelangsungan Hidup Dan Pertumbuhan Larva Terhadap Padat Tebar Ikan Tambakan (Hellostoma Temmincki. C.v)

Fish Tambakan (H. temmincki. CV) is one of the freshwater fish species from the tropics, precisely Southeast Asia. Currently the presence of fish gouramis (H. temmincki. CV) already scarce, and threatened that should be preserved. One effort that can be done to preserve this fish is through cultivation, Density is closely related to the production and the expected growth rate of fish. Activities carried out for 5 months, in hectery Fish Seed Center (BBI) Tempino, District Mestong, Kabupten Muaro. Test fish are fish larvae Tambakan (H. temmincki. CV) of 71 400 individuals. The container used is aquarium measuring 42.5 x 40 x 40 cm, with a height of 10 cm of water as much as 12 aquariums. This research is a design environment completely randomized design (CRD) with 4 treatments and 3 Deuteronomy. The results of this study to the best stocking density is treatment A (200 individuals / liter) which resulted in the percentage of survival of the highest of 86.21%., Average length and weight growth - average yield growth of average length - average 1.50 cm / tail and average weight - average 0159 g / tail and average daily growth - average 0.00396 grams / tail

Analisis Laju Infiltrasi pada Tutupan Lahan Perkebunan dan Hutan Tanam Industri (HTI) di Daerah Aliran Sungai (DAS) Siak

The change in land use may affect the availability of ground due the change of infiltration in to the soil. One of the significant factors that can increase infiltration rate is vegetation coverage. The purpose of this study is: (1) to determine the infiltration rate of 4 type of vegetation land cover and (2) to determine the land cover classification based on the average value of the infiltration capacity. The research was conducted in 4 different land cover : immature palm oil plantation, mature palm oil plantation, rubber plantation and acacia Industrial plantation forest. Infiltration test for each land cover was processed at 8 points on 4 soil types and the obtained data was processed using Horton infiltration method. Based on analysis resulting using Horton infiltration method, immature palm oil plantation with 0,54 cm/hour of infiltration capacity is classified as group B (medium surface flow), oil palm plantation with 0,18 cm/hour of infiltration capacity as group C (between high and medium surface flow), rubber plantation with 0,92 cm/hour of infiltration capacity as group A (low surface flow), and acacia plantation area with 0,91 cm/hour of infiltration capacity as group A (low surface flow). Based on the regression result between the actual infiltration rate and Horton infiltration acquired a very real relation, so that Horton infiltration method can be used to estimate infiltration rate of four types of land cover in Siak Watershed

The properties and interaction of auxins and cytokinins influence rooting of shoot cultures of Eucalyptus

Success in Eucalyptus micropropagation varies with genotype. Although some protocols have proven suitable for suites of clones, many genotypes are recalcitrant to rooting. Their micropropagation is addressed empirically through the manipulation of auxins and cytokinins, which work antagonistically to produce roots and shoots, respectively. Rooting success of three genotypes with 0.1 mg/l indole-3-butyric acid (IBA) was initially recorded as 87, 45 and 41% for clones 1, 2 and 3, respectively. Further studies using the auxin signal transduction inhibitor ñ-chlorophenoxyisobutyric acid (PCIB) or the auxin conjugation inhibitor dihydroxyacetophenone (DHAP) indicated that the poor rooting response of clone 2 was not due to deficient auxin signal perception or auxin conjugation. Omitting kinetin during elongation, followed by auxin-free rooting, significantly increased root production in clone 2 (from 45 to 80.3%), but had no effect on clone 1. Gas chromatography-mass spectrometry (GC-MS) analysis of auxins and kinetin of shoots, prior to rooting, revealed a strong relationship (R2 = 0.943) between rootability and the shoot kinetin:auxin. Replacing kinetin with the less stable trans-zeatin significantly increased rooting of clone 2 (from 19 to 45%) and clone 3 (31 to 52%). It is suggested that root induction in poor-rooters is dependent on exogenous cytokinin depletion from in vitro shoots.Key words: Eucalyptus, phytohormone interaction, root quality

The Impact of the COVID 19 Pandemic on Stock Market Volatility: Evidence from a Selection of Developed and Emerging Stock Markets

This study examines the impact of the COVID 19 pandemic on the stock markets of China, India, Pakistan, the UK and the US using Generalised Autoregressive Conditional Heteroscedasticity (GARCH) and Threshold GARCH models with COVID 19 as an exogenous dummy variable in the variance equation. The sample period of 2016 – 2021 is divided into two sub-periods: the pre-COVID 19 period and the COVID 19 period. The results of the study indicate that the COVID 19 pandemic had a significant impact on the stock market volatility of the sample markets. Results from both the GARCH and Threshold GARCH models further confirm that there was persistent volatility in these markets and that this volatility increased as a result of the pandemic. In addition, the Threshold GARCH results indicate that the asymmetric term was significant in all markets indicating that bad news, such as the pandemic, had a stronger impact on the conditional variance of the returns as compared to good news. In addition, the results further confirm that the US market had no significant impact on the volatility of the Chinese market during the pandemic. The results have important implications for (i) international investors regarding portfolio management and investment risk minimisation in situations like the COVID 19 pandemic; and (ii) policymakers in terms of how they respond to any future pandemic

The Impact of the COVID 19 Pandemic on Stock Market Volatility: Evidence from a Selection of Developed and Emerging Stock Markets

This study examines the impact of the COVID 19 pandemic on the stock markets of China, India, Pakistan, the UK and the US using Generalised Autoregressive Conditional Heteroscedasticity (GARCH) and Threshold GARCH models with COVID 19 as an exogenous dummy variable in the variance equation. The sample period of 2016 – 2021 is divided into two sub-periods: the pre-COVID 19 period and the COVID 19 period. The results of the study indicate that the COVID 19 pandemic had a significant impact on the stock market volatility of the sample markets. Results from both the GARCH and Threshold GARCH models further confirm that there was persistent volatility in these markets and that this volatility increased as a result of the pandemic. In addition, the Threshold GARCH results indicate that the asymmetric term was significant in all markets indicating that bad news, such as the pandemic, had a stronger impact on the conditional variance of the returns as compared to good news. In addition, the results further confirm that the US market had no significant impact on the volatility of the Chinese market during the pandemic. The results have important implications for (i) international investors regarding portfolio management and investment risk minimisation in situations like the COVID 19 pandemic; and (ii) policymakers in terms of how they respond to any future pandemic

Pengolahan Limbah Cair Industri Tahu Menggunakan Tanaman Typha Latifolia dengan Metode Constructed Wetland

Tofu industry is a domestic industry largely do not have sewage treatment units, wherewastewater directly discharge into sewers or water bodies without treatment. The aims ofstudy observation the ability of constructed wetland using T. latifolia to removal, COD andTSS. The research variations were plant and detention time. Constructed wetland reactorusing plastics with dimension 50, 36, 31cm, in length x width x height and soil mediathickness of 10 cm, 5 cm sand and 5 cm gravel. T. latifolia plant density 0, 0,5, 0,75 and 1g/cm2, and variations detention time 1,2, and 3 day. Optimal results were obtained in plantsTypha latifolia 1 g/cm2 and detention time day to 3 there are COD 200 mg/L and efficiency of92,70%; TSS 153 mg/L with efficiency 87,90%;. Anova analysis results α = 5% show thevalue COD 98,8%; and TSS 92,8%. Wich explains that the plant density factor and detentiontime affect the the concentration reduction COD and TSS

Prediksi Emisi Karbon Dioksida dari Kegiatan Transportasi di Kecamatan Bukit Raya Kota Pekanbaru

The population of Pekanbaru City grows increasingly every year, especially in Bukit Raya Sub-district. The higher number of motorcycle used by the people as a transportation directly affect the amount of CO2 emissions generated from each vehicles. This study aims to calculate the volume of vehicles and predict CO2 emissions from the number of vehicles in Bukit Raya District. The methodology used in this study is the calculation of the number of vehicles on Sudirman Street, Teuku Bey and Karya I, the calculation of the conversion of the number of vehicles with units of passenger cars (SMP), and calculation of CO2 emissions on effective and non effective day in Bukit Raya District. Total emissions generated from transport activities in Bukit Raya District are 422 ton CO2 / day on effective day and 241,46 ton CO2 / day on non effective day