Judul: Pengaruh Penambahan FABA dan Lignit dalam Kompos terhadap Sifat Kimia dan Pertumbuhan Nanas (Ananas comosus) pada Ultisol
Abstrak: Degradasi pada Ultisol disebabkan oleh kegiatan monokultur secara terus-menerus dicirikan dengan pH, kadar bahan organik, dan unsur hara rendah, serta kadar aluminium yang tinggi. Untuk mengatasi degradasi Ultisol demikian, digunakan amelioran berupa kompos. Namun, penggunaan kompos sebagai amelioran belum mendapatkan hasil yang optimal terhadap peningkatan kualitas Ultisol. Kompos kurang dalam menyediakan unsur hara, sehingga diperlukan penambahan fly ash dan bottom ash (FABA) maupun lignit dalam kompos. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh penambahan FABA dan lignit dalam kompos untuk memperbaiki kualitas Ultisol yang ditanami nanas, serta mengetahui pengaruh penambahan FABA dan lignit dalam kompos terhadap pertumbuhan serta kadar hara dalam daun nanas. Perlakuan dalam penelitian ini disusun menggunakan rancangan petak terbagi dalam rancangan acak kelompok dengan petak utama adalah teknik aplikasi palir (P) dan tebar (T) serta anak petak adalah kompos 100% (K), kompos 75%+FABA 25% (KF), dan kompos 70%+FABA 20%+ lignit 10% (KFL). Perbandingan fly ash dan bottom ash adalah 6:1, serta bottom ash dan lignit telah lolos ayakan 1 cm. Amelioran diberikan dengan dosis 50 ton ha-1. Tanaman uji yang digunakan adalah bibit nanas klon GP3 sucker kelas besar dan dilaksanakan di blok 86-A kebun PT. Great Giant Pineapple. Hasil penelitian ini menunjukkan bahwa penambahan FABA dan lignit dalam kompos meningkatkan pH, karbon organik, kejenuhan basa, kalsium-, magnesium-, natrium-dapat dipertukarkan, dan seng serta menurunkan kadar aluminium dapat dipertukarkan pada Ultisol. Penambahan FABA dan lignit dalam kompos juga meningkatkan kadar kalsium, belerang, dan seng dalam daun. Disamping itu, penambahan FABA dalam kompos meningkatkan D-leaf index tanaman nanas. Pemberian amelioran lebih efektif jika diaplikasikan secara palir dibandingkan dengan tebar. Penggunaan FABA dalam kompos sebagai amelioran diharapkan dapat meningkatkan kualitas Ultisol terdegradasi dan produktivitas tanaman serta mengurangi dosis kompos yang digunakan pada tanaman nanas., Degradation of Ultisol is caused by continuous monoculture activities and is characterized by low pH, organic matter, nutrient content, and high aluminium contents. In response to such Ultisol degradation, ameliorants in the form of compost are used. However, using compost as an ameliorant has yet to obtain optimal results toward improving the Ultisol quality. The lack of ability of compost to supply nutrients is because the nutrients in compost are easily lost due to leaching, so it is necessary to add coal ash consisting of fly ash and bottom ash (FABA) also lignite in compost. This study aimed to determine the effect of compost-enriched with FABA and Lignite to improve the Ultisol's quality planted with pineapple and also on its growth and nutrient levels in the leaves. The treatments in this study were arranged using a split plots design in a randomized block design, with the main plot being the application technique of row (P) and spread (T). The subplots were 100% compost (K), 75% compost + 25% FABA (KF), and 70% compost + 20% FABA + 10% lignite (KFL). The ratio of fly ash and bottom ash was 6:1, and bottom ash and lignite had passed a 1 cm sieve. Ameliorants were applied at a dose of 50 tons ha-1. The test plants used were pineapple seedlings of large class clones GP-3 sucker and were carried
Keyword: Compost, Faba, Lignite, Pineapple, Ultisol

Judul: Improvement of Soil Quality at Pineapple Plantation PT. Great Giant Pineapple uses FABA and Lignite Enriched Compost
Abstrak: Penurunan kualitas tanah berupa penurunan kesuburan tanah telah terjadi di PT. Great Giant Pineapple (GGP) akibat budidaya nanas secara monokultur sejak 1980-an. Kualitas tanah bisa diperbaiki melalui bahan pembenah tanah. Aplikasi kompos sebagai pembenah tanah telah dilakukan oleh PT. GGP, namun pengaruhnya belum optimal, sehingga diperlukan penambahan pembenah tanah lain. Contoh alternatif pembenah tanah yang lain adalah limbah abu batubara (fly ash dan bottom ash atau FABA) dan batubara muda (lignit). Penelitian ini bertujuan memperbaiki kualitas tanah secara kimia di perkebunan nanas PT. GGP melalui pemberian kompos diperkaya FABA dan lignit. Penelitian dilakukan secara eksperimental di lahan percobaan Research and Development PT. GGP Blok 86 A menggunakan Rancangan Petak Terbagi. Perlakuan terdiri atas bahan pembenah tanah kompos, kompos+FABA, dan kompos+FABA+lignit yang diaplikasikan secara tebar dan palir. Hasil penelitian menunjukkan bahwa pengkayaan kompos dengan FABA dan lignit meningkatkan beberapa sifat kimia pembenah tanah diantaranya pH, C-organik, P-total, Ca, Mg, K, Mn, dan Cu. Aplikasi kompos+FABA+lignit secara palir lebih baik dalam memperbaiki beberapa sifat kimia tanah di lahan PT. GGP, diantaranya menurunkan kemasaman tanah serta meningkatkan C-organik, N-total, P-total, P-tersedia, K-dd, Ca-dd, Mg-dd, Na-dd, KTK, dan kejenuhan basa. Perlakuan tersebut belum memperlihatkan pengaruh yang lebih baik dalam meningkatkan N-total, P-tersedia dan K-dd dibandingkan dengan kompos murni., Degradation in soil quality, such as a decrease in soil fertility has occurred at PT. Great Giant Pineapple (GGP) due to monoculture pineapple cultivation since the 1980s. Soil quality can be improved by the application of soil ameliorants. The application of compost as a soil ameliorant has been carried out by PT. GGP, but the effect is not optimal, so it is necessary to add other soil ameliorants. Other soil ameliorant alternatives are coal ash waste (fly ash and bottom ash or FABA) and lignite. This study aims to improve soil quality, especially its chemical properties in the pineapple plantation of PT. GGP with the application of FABA and lignite enriched compost. The research was conducted experimentally at the Research and Development experimental area of PT. GGP Block 86 A uses a Split Plot Design. The treatments consisted of compost, compost+FABA, and compost+FABA+ lignite which is a soil ameliorant material that is applied by spreading it and given in the planting row. The results showed that the enrichment of compost with FABA and lignite increased several chemical properties of the soil ameliorants, including pH, C-organic, P-total, Ca, Mg, K, Mn, and Cu. The application of compost+ FABA+lignite, especially in planting rows, was better in improving some soil chemical properties in PT. GGP, among others, reduces soil acidity and increases C-organic, N-total, P-total, P-available, K-dd, Ca-dd, Mg-dd, Na-dd, CEC, and base saturation. This treatment has not shown a better effect in increasing the total N, P-available, and K-dd compared to compost.
Keyword: compost, FABA, lignite, soil ameliorant

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
Keyword: