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JOHAN A. ROMBANG
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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
ERODIBILITAS TANAH PADA KAWASAN HUTAN LINDUNG GUNUNG MASARANG Ayu Natia H. Djufri; Johan A. Rombang; Johny S. Tasirin
COCOS Vol. 13 No. 3 (2021): EDISI JULI-SEPTEMBER 2021
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v4i4.34506

Abstract

Abstract This research aims to assess the value of soil erodibility in the Mount Masarang Protected Forest area Rurukan Village, Tomohon City. The research was conducted on 3 types of land cover, namely grasses/reeds land, agricultural land and secondary forests. For each type of land cover, 3 soil samples were taken. Soil sample points were determined purposively, the soil structure was observed and the soil permeability was measured using a permeameter with the constant water level method (Constant Head). Soil samples were analyzed in the laboratory to obtain data on soil texture and soil organic matter content, then K value was calculated according to the USLE method. The results showed that the highest soil erodibility was on agricultural land at 0.37 ton.jam.ft-tonf-1 .in-1 which is classified as a rather high class, while the lowest was on grass/reed land of 0.19 ton.jam.ft-tonf-1 .in-1 belongs to the low erodibility class. Factors causing high soil erodibility on agricultural land were a low clay content, higher silt and lower organic matter so that the soil is more easily eroded.Keywords: soil erodibility, protected forest, Mount Masarang.
FLUKTUASI SUHU UDARA PADA EKOSISTEM HUTAN KOTA Nonong Krisnawati Loha; Johan A. Rombang; Josephus I. Kalangi
COCOS Vol. 14 No. 3 (2022): EDISI JULI-SEPTEMBER 2022
Publisher : Universitas Sam Ratulangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35791/cocos.v8i8.37237

Abstract

Abstract This study aims to determine fluctuations in air temperature in urban forest ecosystems. This research was carried out in 3 (three) places, namely Tomohon urban forest (921 meter above sea level), Bitung urban forest (Danowudu 248 meter above sea level) North Minahasa urban forest (Kenangan 342 meter above sea level), conducted in November 2021, for 5 days. Observation plots measuring 25x25 m at each location. The diameter of the crown was measured using the "Improvised technique". The results showed that, Danowudu urban forest had a tree density level of 0.0192 trees/m² with a diversity of 6 tree species, Tomohon urban forest had a tree density of 0.0224 trees/m² with a diversity of 3 tree species, and Kenangan urban forest had a tree density of 0.0272 trees/m² with a diversity of 5 tree species, the highest temperature fluctuation was obtained in the Kenangan urban forest at 7.48°C and the lowest at 5.08°C in the Tomohon urban forest. Keywords: Air temperature, fluctuation, urban forest
Co-Authors A. LUMINGKEWAS 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 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 Pangemanan, Euis F. S. PASKALINA, YULIA Prayitno Prayitno 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 Sumanto Basahona Sumanto Basahona Timur Kogoya Timur Kogoya, Timur TUMBELAKA, S. Wakiah, Sitti Yorri Y. J. Sanger YULIA PASKALINA Yusran Ilyas, Yusran Zulfitri Lawe