The Effect of Water Quality on Growth of Microalgaes Chlorella pyrenoidosa

The diversity of microalgae on earth is very high, the high diversity of microalgae allows us to obtain microalgae that have the potential to produce large amounts of oil. In addition, the use of microalgae as a source of biodiesel does not interfere with the food supply. This is because microalgae do not compete with food. The results of the analysis showed that the parameters that passed the water quality standard were BOD in the range of 0.990-90.76 mg/l, COD in the range of 3.093 -283 mg/l, and phosphate in the range of 0.01-0.21 mg/l. Judging from the color and smell, the waters that are closer to the cages will be greener in color accompanied by the smell of fish mixed with fishy feed and feel thick. COD content ranged from 3.093 mg/l-269.5 mg/l. This is caused by the high concentration of organic matter in the waters. The quality of the waters of Lake Toba which is classified as not good is the measurement of color, smell, taste, BOD, COD, and Phosphate in the waters. Which are classified as good temperature, turbidity, pH, Ammonia, and Nitrate. The level of fertility of the waters of Lake Toba in terms of the abundance of phytoplankton is included in the fertile category. If it is categorized at the level of pollution through the diversity index, then the waters are included in the moderately polluted category

Potret Model Pembelajaran Daring Online terhadap Perkuliahan Praktikum Masa Pandemi Covid-19

Dalam kurun waktu setahun belakangan, kita semua menghadapi wabah pandemi dari virus yang membuat seluruh manusia dan mobilitasnya terganggu, termasuk aspek pendidikan, kesehatan, ekonomi, industri bahkan sosial – budaya. Terlebih kita selaku tenaga pendidik dan menyentuh langsung dengan dunia pembelajaran bagi mahasiswa, turut terkena dampak dalam pengajaran yang awalnya tatap muka beralih ke sistem pembelajaran daring, oleh karena itu tujuan dari dilakukannya penelitian ini mengarah untuk proses perkuliahan secara virtual dan sistem secara online. Pada prosesnya, metode yang digunakan bagi para pengajar khususnya dosen adalah virtual dan online yang bisa membantu proses pengajaran terutama mata kuliah praktikum di Program studi Biologi. Adapun hasil dari dilakukannya korespondensi dari tahap wawancara antara dosen dan mahasiswa di semester VI, terlebih di pembelajaran praktikum yang sebelumnya dilakukan di laboratorium dan dimasa pandemi menjadi virtual. Pembelajaran daring menjadi pilihan efektif bagi para dosen dan mahasiswa dalam membantu program pemerintah belajar dari rumah (Daring) dan mengurangi mobilitas seperti sedia kala, dan kita berharap agar pandemi segera berlalu dan covid-19 menjadi masalah kita bersama demi mengurangi dampak dari wabah Covid-19 in

Arthropoda Community Structure in Conservation Forest and Oil Palm Plantation in Java Tongah Village Area, Hatonduhan District, Simalungun Regency

The research about composition and structure of Arthropoda community was conducted at oil palm plantations Arthropoda were collected at oil palm plantation, conservasion forest and forest edge sites (between conservation forest and plantation area) by survey method with systematic random sampling for arthropoda in litter and soil. A total of four Arthropoda species that belonging to 2 orders, 3 families, 4 general and 57 individuals was collected. The highest number of individuals Isotomiella sp. (14 ind) family Isotomidae. Arthropoda community composition consists of 3 families & 4 species: Neanuridae (Lobella sp.), Brachystomellidae (Brachystomella sp.) & Isotomidae (Isotomiella sp. & Folsomides sp.), Arthropoda community structure The highest density is in the litter location I (16 ind / m2) while the lowest density is in location III (3.56 ind / m2). The highest soil density is in location I (4,538.56 ind / m3) & the lowest density is in location III (789,761 ind / m3). The highest relative density is location III (100%) & the lowest relative density is found in location I (litter, 5.8%) & (soil, 8.9%). The highest Shannon-Wiener diversity index, both litter and soil, were found in location I (litter 1.28) & (soil, 1.38) and the lowest diversity index was found in location III (0). The highest similarity index for Sorensen was location III (75.71%) and the lowest was the comparison between locations II & I (20%)

Analysis Variation Paddle Wheel With Photovoltaic Form Cultivation with Consumption Electricity

The main problem that is often found in the failure of microalgae production is poor water quality during the maintenance period. One of the causes of deteriorating water quality is the lack of oxygen which endangers microalgae which can inhibit cell growth so that it can reduce its productivity. On this basis, efforts are needed to refresh the water or aeration to help increase the dissolved oxygen (DO) level in the microalgae growth container using a paddle wheel. The development of an aerator blade design that has optimum efficiency is needed to reduce high electricity consumption and see more effective cell growth

STRUKTUR KOMUNITAS POHON MANGROVE DI KAWASAN DESA BAGAN ASAHAN KECAMATAN TANJUNG BALAI KABUPATEN ASAHAN

Mangrove forest is a plant that grows in coastal areas or in coastal areas, and estuarine areas that have an ecological function, namely as the last protector from the waves of sea water after coral reef ecosystems and seagrass ecosystems, as sediment catchers, foraging for fish, as fish spawning grounds and as fish breeding grounds. Research on the Community Structure of Mangrove Plants in the Bagan Asahan Village Area, Tanjung Balai District, Asahan Regency was conducted in August 2020 with the aim of knowing the structure of the mangrove community and environmental factors that affect the existence of mangrove plants in Bagan Asahan Village. The method used in observing the structure of the mangrove plant community is using the quadrant transect method by analyzing species density, relative density, species frequency, relative frequency, species dominance, relative dominance, and important value index at the tree level. Based on the results of the study, it was found that Avicennia marina, Bruguiera gymnorrhiza and Rhizopora apiculata had the highest INP at the tree level. Further research is needed on the structure of the mangrove community in the same place and with different stations so that the mangrove data can represent the entire area of Bagan Asahan Village. The author suggests to further preserve mangroves

Mangrove Plant Community Structure, Sungai Apung Village, Tanjung Balai Sub-District, Asahan District, North Sumatra Province

Mangroves are a type of vegetation found in tropical coastal areas. In general, mangrove vegetation thrives in sloping coastal areas or near river estuaries and beaches that are protected from waves. The physical function of mangrove forests is to keep the coastline stable, protect the coast from erosion, reduce storms and waves, and catch sediment, while the biological function of mangroves is as a spawning place or residence, shelter for shrimp, crabs, shellfish, and other animals. Research on Mangrove Plant Community Structure in the Kwala Indah Village Area was carried out in August–November 2023 with the aim of determining mangrove types, mangrove diversity and uniformity, dominance, the Important Value Index (INP), and mangrove canopy cover in Singai Apung Village. The method used to observe the community structure of mangrove plants is to use the quadrant transect method by analyzing species density, relative density, species frequency, relative frequency, species dominance, relative dominance, and important value index at the tree level. , saplings and seedlings, as well as canopy cover. Based on the research results, 10 species were found, namely Avicennia alba, Avicennia lanata, Bruguiera cylindrica, Bruguiera sexangula, Excoearia agallocha, Lumnitzera littorea, Rhizophora apiculata, Rhizophora mucronata, Sonneratia alba, and Xylocarpus granatum. Rhizopora mucronata, which has INP, diversity in the medium category, and uniformity in the high category, has the highest dominance in Rhizophora mucronata. Canopy cover is in the dense category

Utilization of Palm Oil Mill Effluent (POME) Liquid Waste to Increase Density and Growth Rate of Microalgae Chlorella Pyrenoidosa

Microalgae Chlorella pyrenoidosa is a microalgae that has the potential to have various roles, especially as a bioabsorbant for organic waste. The growth of the oil palm plantation industry is also directly proportional to the increase in waste generated from the CPO production process, namely POME Waste (Palm Oil Mill Effluent). POME waste has a high nutrient content so that it can be utilized by the microalgae Chlorella pyrenoidosa. This study aims to utilize POME waste to increase the growth of Chlorella pyrenoidosa. Microalgae cultivation had a significant effect on the 1:2 treatment and 1:3 treatment when compared to the control cultivation medium with the highest cell density values ​​of 263(106cells/ml) and 279(106cells/ml) respectively. Injection of POME waste into microalgae rearing media will have an impact on increasing the growth of Chlorella pyrenoidosa microalgae

Mangrove Community Structure in Pematang Sei Baru Village, Tanjung Balai District, Asahan Regency

Coastal and marine areas are an integrated ecosystem and are interconnected with each other, so they have a mutual correlation. In a coastal ecosystem, there is an exchange of matter and energy that takes place in the system and with other external system components. Based on the importance of the role of mangrove ecosystems in a body of water and the lack of information about the structure of mangrove communities in Pematang Sei Baru Village, Tanjung Balai District, Asahan Regency, North Sumatra, this research is important to be carried out to determine the condition of mangrove ecosystems and can provide understanding to the community about the importance of ecosystems for coastal areas. The data analysis used in this study is both descriptive and quantitative. The data analysis used includes diversity and uniformity index, dominance, mangrove community structure, and canopy cover. The highest diversity in trees is found at station 3, with a value of 2.20, and the lowest, with a value of 2.12, at station 2. The highest uniformity in trees is found at station 2, with a value of 0.96, and the lowest at station 5, with a value of 0.93. The highest dominance value was in Rhizophora mucronata with a value of 15.75%, Xylocarpus granatum with a value of 11.51%, and Bruguiera cylindrical type with a value of 10.73%. 1 highest INP value is the type of Rhizophora mucronata with a value of 55.79% and canopy cover in the medium category. Based on the results of observations made at the location of this study, there are many remnants of logging carried out by the surrounding community, which, if left unchecked, will lead to reduced land, which will greatly affect the ecosystem in it. Therefore, the role of the government is expected in conducting supervision in this area

Mangrove Plant Community Structure of Kwala Indah Village, Batu Bara Regency

Coastal areas are transitional areas between land and marine ecosystems that have high biological productivity. Mangroves are a type of plant that grows in coastal areas or river estuaries and has an ecological function by acting as the last defense against sea waves after coral reef and seagrass ecosystems, as sediment traps, as a place to find fish food, as a fish spawning ground, as a shelter, and as a place for fish farming. Mangrove Plant Community Structure Research in the Kwala Indah Village Area was conducted in August–October 2023 with the aim of knowing the types of mangroves, mangrove diversity and uniformity, dominance, Important Value Index (INP), and mangrove crown cover in Kwala Indah Village. The method used in the observation of mangrove plant community structure is to use the quadrant transect method by analyzing species density, relative density, species frequency, relative frequency, species dominance, relative dominance, and important value index at the tree, sapling, and seedling levels, as well as crown cover. Based on the results of the study, 7 species were found, namely Xylocarpus granatum, Xylocarpus mekongensis, Rhizophora apiculata, Rhizophora mucronata, Soneratia alba, Bruguiera parviflora, and Excoecaria agallocha.  Xylocarpus and Rhizopora have the highest INP, diversity, uniformity, and dominance. Canopy cover is in the medium category; coastal areas are transitional areas between terrestrial and marine ecosystems that have high biodiversity values

Macrozoobenthoc Diversity on The Mangrove Ecosystem in The Gosong Telaga Selatan Mangrove Ecotourism, Singkil Utara District, Aceh Singkil District

Macrozoobenthos is a group of organisms that live in or on the surface of bottom sediments and have a length of more than 1 mm. One of the macrozoobenthos habitats is the mangrove ecosystem in the Gosong Telaga Selatan Ecotourism Mangrove, North Singkil District, Aceh Singkil Regency. Knowledge that macrozoobenthos can provide food availability for other organisms and as an indication of the suitability of potential water quality, especially pollution indicators, and plays an important role in the decomposition process of organic material in sediment in the mangrove ecosystem, so that the macrozoobenthos community can be used as an indicator of the balance of the mangrove ecosystem. This research aims to identify the diversity, uniformity, and dominance of Macrozoobenthos in the Gosong Telaga Selatan Mangrove Ecotourism Area, North Singkil District, Aceh Singkil Regency. This research uses a combination of two transect methods, namely line transects and quadratic transects. Determining the research location used the purposive sampling technique. Data analysis uses qualitative and quantitative analysis. The research results show that there are 7 Macrozoobenthos species, consisting of 3 classes, with a total of 182 individuals. Macrozoobenthic diversity in the ecosystem area in the Gosong Telaga Selatan Mangrove Ecotourism, North Singkil District, Aceh Singkil Regency is classified as moderate with a diversity index of Ĥ= 1.35-1.75, the uniformity index is classified as stable, ranging between E= 0.76-0.93, and the dominance index is classified as low