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PENGARUH MEDIA TANAM TERHADAP PERTUMBUHAN BIBIT JABON MERAH (Anthocephalus macrophyllus (Roxb) Havil) Yusran Ilyas; Johan A. Rombang; Marthen T. Lasut; Euis F.S. Pangemanan
COCOS Vol. 6 No. 12 (2015)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v6i12.8511

Abstract

ABSTRACT  This research studied the effects of planting media on the growth of red Jabon (Anthocephalus macrophyllus (Havil) Roxb) seedlings. The objective was to determine the effect of several mixtures of soil, sand, and manure as a planting media for growing seedlings of red Jabon. The research was conducted in two months from April to July 2013, using a completely randomized design (CRD). There are 5 treatments of planting media, namely M1, M2, M3, M4, and M5. Each treatment has 5 replications and each replication was planted with one individual plant. Measured variables were plant height, trunk diameter and leaf number Analysis of variance was done and if there was a significantly different among treatments, a folowing LSD test was carried out. Increments of plant height were significantly different at 63 day after planting,(DAP) whereas increments of trunk diameter were significantly different at 49 DAP. Mixtures of soil, sand and manure showed significantly different effects, and adding sand to the soil with relatively high clay content (> 40%) was important to improve air and water circulation in planting media. Keywords: Media Plant, Red Jabon, Growth
Analisis Koefisien Kekasaran Sungai Di Sungai Sario Dengan Persamaan Manning Adenancy A. Montjai; Johan A. Rombang; Josephus I. Kalangi
COCOS Vol. 6 No. 12 (2015)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v6i12.8633

Abstract

ABSTRACT Analysis of River Roughness Coefficient in Sario River with Manning Equation Sario river is the main river of Sario Watershed.  Due to rapidly increasing population, protected area alongside river border had become settlement.  This causes a decrease of river channel capacity so that flood could happen as a case in January 2014.  Manning equation is the formula frequently used to calculate the flow capacity of open channel. The purpose of this research is to determine roughness coefficient of Sario River by using Manning equation. This research was done in three months starting from January 2015 to March 2015.  Observed and measured variables were river width, top width, bottom width, water depth, river channel depth, river pseudosection profile, flow velocity, gradient of bottom channel, and channel description.  Method applied was survey method and the determination of measurement and observation points was done with certain consideration (purposive sampling).  The averages of calculated roughness coefficients of Sario River are 0,049 for upstream, 0,050 for middlestream, and 0,060 for downsrtream. The average of Sario River roughness coefficient is 0,048.  Garbage and water countaining dispersed particles caused roughness coefficient greater than secondary data for natural channel. Keywords : River Roughness, Manning equation, Sario River
PENGARUH PEMBERIAN PUPUK KOMPOS TERHADAP PERTUMBUHAN BIBIT JABON MERAH (Anthocephalus macrophyllus) Etivera Safuf; Alfonsius Thomas; Johan A. Rombang; Josephus I. Kalangi
COCOS Vol. 6 No. 17 (2015)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v6i17.9840

Abstract

ABSTRACT  This research studies the effects of compost fertilizer on the growth of red jabon (Anthocepalus macrophyllus) seedling. The method used is completely randomized design, with 5 treatments and 5 replications. No (zero) compost was applied on treatment A as a control, 25 grams of compost on treatment B, 50 grams of compost on treatment C, 75 grams of compost on treatment D, and 100 grams of compost on treatment E. Based on recommendation, growth media used in this research was a mix of soil and sand, with a ratio of 3:2. Variables observed were increase in plant height, increase in stem diameter, increase in number of leaves, and the dry weight of shoot. Results showed that the application of compost fertilizer to red jabon seedling made significant differences in the increase of plant height and stem diameter. Key words: red jabon seedling (Anthocephalus macrophyllus) compost fertilizer  zeorganik
IDENTIFIKASI JENIS TUTUPAN LAHAN DI KAWASAN KPHP POIGAR DENGAN METODE MAXIMUM LIKELIHOOD Abdul M. Muhammad; Johan A. Rombang; Fabiola B. Saroinsong
COCOS Vol. 7 No. 2 (2016)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v7i2.11451

Abstract

ABSTRACTLand cover of KPHP Poigar constantly has been changing. Mapping and identification by Maximum Likelihood method was more accurate than another method. Purpose of this research is to analyze the capability Maximum Likelihood Classification to map and identify the type of land cover in KHPH Poigar area. This research was carried out in September – November 2015 and in four steps. The first step was Image Pre-processing such a Layer Stacking process. Second step consists of OIF (Optimum Index Factor) Calculation, Cropping, and Visual Image Interpretation. Third step was Ground check in KPHP Poigar area. Fourth step were Image Analyzing with Maximum Likelihood Classification method and Accuracy Test. The value of accurate test for Overall Accuracy (OA) was 85,04 percent and for Kappa Accuracy (KA) was 80,97 percent classified into Almost Perfect Agreement category. The result of land cover classification based on image analyzing with Maximum Likelihood Classification method in KHPH Poigar indicated that there are 5 types of land cover, they are forest (21597,21 ha), bareland (5799,69 ha), bush (5612,58 ha), farmland (5649,12 ha) and mixed farmland (2942,37 ha).Keywords : Maximum Likelihood, KPHP Poigar, Type of Land Cover, Accuracy
PERTUMBUHAN Grynops vesteegi (Giil) PADA BERBAGAI DOSIS PUPUK ORGANIK CAIR G-TONIK Timur Kogoya; Marthen T. Lasut; Johan A. Rombang
COCOS Vol. 7 No. 2 (2016)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v7i2.11904

Abstract

ABSTRACTThe study of the growth of Gyrinops vesteegii (Giil) plant by applying various doses of G-tonic liguid organic fertilizer had been carried out in the Greenhouse of the Faculty of Agriculture, University of Sam Ratulangi Manado.The purpose of this study is to find out the effect of various doses of liguid organic fertilizer on the growth of the Gyrinops vesteegii plant. This study is conducted by using Randomized Complete Block Design ( RCBD) with 5 treatments and 5. Replications each replication consists of one plant. The treatments applied were P1 (Control, without fertilizer), P2 0.125 cc of G – tonic liguid organic fertilizer given every application. P3 0,25 cc, P4 0,375 cc, and P5 0,500 cc. The variables observed were the increase of plant,s height as well as of stalk diameter. The data obtained will be analyzed by using Analisisv of Variance (anova) at 5% level.The result of the study showed that the application of G-tonic liguid organic fertilizer to Gyrinops vesteeglii plant seedling did not have significant effect on the increase of plant,s height and stalk,s diameter. This is due to the liguid organic fertilizer did not have yet effect toward the Gyrinops vesteeglii plant seedling in a period of 35
PENGARUH PUPUK DAUN DAN NAUNGAN TERHADAP PERTUMBUHAN BIBIT GAHARU Gyrinops verstegii (Gilg) Domke DI BAWAH CEKAMAN AIR. Anggreine H. Mentang; Johan A. Rombang; Marthen T. Lasut; Alfonsius Thomas
COCOS Vol. 7 No. 3 (2016)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v7i3.12152

Abstract

ABSTRAKThis research aims to know the influence of leaf fertilizers and shade on the growth ofGyrinops verstegii (Gilg) Domke under water stress. This research was conducted in the greenhouse of Faculty of Agriculture, University of Sam Ratulangi Manado, from June to August2013. Spit plot design is used in this research. Shade as main plot consists of two levels,namely: 1 layer of paranet N1 (light intensity ± 40%) and 2 layers of paranet N2 (lightintensity ± 16%). Doses of fertilizer as sub-plot consists of 3 levels: P0 as a control (nofertilizer), P1 0.012 g/plant and P2 0.024 g/plant. The fertilizer was given every week for 2months. The effects of both shading and fertilizer treatments were not significant on plantheight and stem diameter under water stress.Keywords: Gyrinops verstegii, water stress.
PENGARUH MEDIA TANAM TERHADAP PERTUMBUHAN SEMAI Aquilaria malaccensis Lamk. DI PERSEMAIAN Rinna Mamonto; Johan A. Rombang; Marthen Th. Lasut
COCOS Vol. 10 No. 3 (2018)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v1i1.22201

Abstract

Abstract The increasing of market demand along with high selling price of agarwood encouraged people to get more production by cutting down the agarwood-producing trees. As a result, the population of gaharuproducing trees become decrease and needs to be conserved. Conservation efforts is collateral with production continuity to anticipating market demand can started from planting and cultivating. One of them is the provision of quality seeds that supported by good planting media. This research studied the effect of media on the growth of Aquilaria malaccensis Lamk.,seedlings while the planting media were soil, husk, and compost. The method was Completely Randomized Design method consisting of 6 treatments and 5 replications. Each replication consists of 1 plant, so there are 30 experimental units. Treatment is distinguished based on volume comparison of planting media, namelytreatment 1 (P1) soil, treatment 2 (P2) compost, treatment 3 (P3) husk, treatment 4 (P4) combination of soil:compost (50%: 50%), treatment 5 (P5) combination of soil: husk (50% - 50%), and treatment 6 (P6) combination of compost: husk (50%: 50%).The variables which observed were plant height, stem diameter and number of leaves. The results showed that the treatment of planting media using compost (P2) gave significant effect on the increase in height and number of leaves of Aquilaria malaccensis Lamk.,seedlings.  Key words : Aquilaria malaccensis Lamk., seedlings, soil, compost, husk
KAPASISTAS SALURAN SUNGAI KAROMBASAN Anggraini F. M. Pandeirot; Johan A. Rombang; Fabiola B. Saroinsong
COCOS Vol. 10 No. 3 (2018)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v1i1.22659

Abstract

ABSTRACT Capacity Of Karombasan River Channels  The Karombasan watershed has an area of 270 ha and river length of 3.058 m. The main river, Karombasan River, floods almost every year, possibly because the river channel is not able to accommodate the volume of the flow and thus causing a number of houses on the riverbank to be flooded. This flooding event is very disturbing to the locals. The purpose of this research is to analyze the river in location that often flood. Sampling and observation points were determined through purposive sampling methods at the points of frequent flooding. River capacity was analyzed using the Manning equation. Analysis of current river capacity from points 1 to 5 is 10,82 m³/s, 7,85 m³/s, 12,19 m³/s, 11,03 m³/s, and 5,32 m³/s, respectively.  Keywords : Watershed, flood, river capacity.
ANALISIS KOEFISIEN ALIRAN PERMUKAAN PADA TIGA TIPE PENGGUNAAN LAHAN di TANAH ANDISOL Ikasapta Ramehiang; Johan Rombang
COCOS Vol. 10 No. 7 (2018)
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v1i5.25740

Abstract

ABSTRACT Current changes in land use caused by population growth and development in the development sector are increasing. This has a significant impact on changes in surface flow values, causing the flow coefficient to increase resulting in flooding. One of the important concepts in efforts to control flooding is the surface flow coefficient or commonly represented by C. This number of surface flow coefficients is one indicator to determine whether a watershed has been disturbed (physically). This study aims to calculate the Surface Flow Coefficient (C) in the type of forest land use, shrub land and open land. The method in this study used a randomized block design as a data collection method which was then analyzed using analysis of variants. From the results of measurements carried out in the field, the coefficient of surface runoff of forest land and shrub land is significantly different from open land where in forest land is 0.0019 and shrub land has a value of 0.0013, while open land is 0.0036. From the results of measurements carried out in the field, the infiltration rate in a row is shrub land of 210 mm / hour, forest land of 99 mm / hour and open land of 69.6 mm / hour. Forest land has a smaller infiltration rate compared to shrub land because forest land in the study area is artificial forest planted with vegetation, strata and has a different root system of natural forest. Keywords: surface flow coefficient, infiltration, surface flow
PERANAN PENGGUNAAN LAHAN DI AREA TANGKAPAN SUNGAI TATAARAN TERHADAP EUTROFIKASI DANAU TONDANO Claudio Bonifasius; Johan Rombang Johan Rombang; Josephus Kalangi Josephus Kalangi
COCOS Vol. 12 No. 3 (2020): EDISI JULI-SEPTEMBER 2020
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v7i7.31141

Abstract

ABSTRACTEutrophication is a problem faced by the world today. eutrophication is causedby increasing nutrient concentrations that occur in freshwater ecosystems. Land usechange in this case greatly affects the freshwater ecosystem around the lake. Thisstudy aims to assess the levels of Nitrogen (N) and Phosphorus (P) in the Tataaranriver water flowing into Lake Tondano due land use in the Tataaran river catchmentarea. The method used in this research is survey method and determination ofsampling points based on purposive sampling or the determination according to theresearch objectives, in this case at the outlet of each land use which is then presenteddescriptively for comparison. The results of this study indicate that based on the studyof Nitrogen (N) and Phosphorus (P) levels in the Tataaran river water flowing into LakeTondano, the largest contribution transported comes from residential land use, namelythe average N value content is 56.86 mg / seconds and P of 217.64 mg / second.Keywords : Eutrophication, Landuse, River of Tataaran
Co-Authors A. LUMINGKEWAS A. Thomas Abdul M. Muhammad Abdul M. Muhammad, Abdul M. Adenancy A. Montjai Adenancy A. Montjai, Adenancy A. Alfonsius Thomas Alfonsius Thomas Alfonsius Thomas Anggraini F. M. Pandeirot Anggreine H. Mentang Anggreine H. Mentang, Anggreine H. Antoneta Kartini Kotangon Astri Vandalia Elisabeth Naray Ayu Natia H. Djufri Belly Ireeuw Budi Utomo Mondolu Christomus Bode Christomus Bode, Christomus Claudio Bonifasius Etivera Safuf Etivera Safuf, Etivera Fabiola B. Saroinsong Fajar Gemilang Sahman Habdi Selpia Habdi Selpia, Habdi Hanny S. G. Kembuan Ikasapta Ramehiang J. I. KALANGI Jaelani ., Husain Johannes E. X. Rogi Josephus I. Kalangi Joshephus I. Kalangi KALANGI, J. I. Kalangi, Josephus Kotangon, Antoneta Kartini LUMINGKEWAS, A. Makarawung, Jerry Malsupri Taher Maria Y.M.A. Sumakud Marthen T. Lasut Marthen T. Lasut Marthen T. Lasut Marthen Th. Lasut Martina A. Langi Meity Rantung Mirna Umagapi Mirna Umagapi, Mirna muriany, vinolya Prisilia Nonong Krisnawati Loha Nurmawan, W. Pangemanan, Euis F. S. PASKALINA, YULIA Prayitno Prayitno Putra, Imam Syah R. Kainde Ragentu, Deris Wijayanti Ramli Sapsuha Reynold P. Kainde Reynold P. Kainde Rinna Mamonto ROGI, JOHANNES E.X. Rogi, Rino ., S. TUMBELAKA Sanger, Yorri Y. J. Santi . Lumingkewas Sapan, Hagi Sitti Wakiah Sukarman Sukarman Sumanto Basahona Sumanto Basahona Telah, Heinsy A.J. Timur Kogoya Timur Kogoya, Timur TUMBELAKA, S. Wakiah, Sitti Walangitan, H. D. Wowor, Andre E. Yorri Y. J. Sanger YULIA PASKALINA Yusran Ilyas, Yusran Zulfitri Lawe