Abstract. Dermiyati, Suharjo R, Telaumbanua M, Ilmiasari Y, Yosita R, Annisa RM, Sari AW, Andayani AP, Yulianti DM. 2019. Population of phosphate solubilizing bacteria in the liquid organic fertilizer created from palm oil bunches and pineapple rhizome. Biodiversitas 20: 3315-3321. Palm oil bunches and pineapple rhizomes are abundant in Indonesia, especially in Lampung Province due to widespread agro-industrial company and they are potential to be used as sources for liquid organic fertilizer. This study was aimed to reveal microbial population within liquid organic fertilizer (LF) which was developed from palm oil bunches (PB) and pineapple rhizome (PR) and their role as phosphate solubilizing bacteria (PSB). The capability to solubilize phosphate was recorded from the clear zone area around the bacterial colony which was cultivated on Pikovskaya’s agar medium. The LF was prepared in three kinds of conditions, namely aerobic, anaerobic, and facultative an aerobic. Isolation was performed every 3 days until 24 days after incubations. The results showed that microbial population in the LF from PR was significantly higher than those developed from PB. Totally, 791 bacterial isolates were obtained from the LF; 490 isolates were achieved from PR (153 isolates from aerobic, 188 isolates from facultative anaerobic, 149 from anaerobic conditions) and 301 isolates were collected from PB (96 isolates from aerobic, 112 isolates from facultative anaerobic, 93 isolates from anaerobic conditions). In the case of isolates that were gained from PB, 166 isolates (55.15%) showed capability to degrade phosphate and 135 isolates (44.85%) did not show any capability as PSB. As for isolates obtained from PR, 269 isolates (54.90%) had capability to solubilize phosphate, meanwhile, the other 221 isolates (45.10%) did not show any capability to solubilize phosphate. Among166 isolates of PSB from PB, 60 isolates had very low capability, 55 isolates had low capability, 34 isolates had medium capability, 10 isolates had high capability and only 7 isolates had very high capability. Meanwhile, from 269 isolates of PSB obtained from PR, 135 isolates had very low capability to solubilize phosphate, 84 isolates had low capability to solubilize phosphate, 32 had medium capability to solubilize phosphate, 14 isolates had high capability to solubilize phosphate and 4 isolates produced very high capability as PSB. In total, 11 chosen isolates were selected from LF developed from both PB (7 isolates) and PR (4 isolates). Therefore, palm oil bunches and pineapple rhizomes contained PSB that can be used as LF.

Masalah dalam penelitian ini adalah rendahnya kemampuan berpikir kritis peserta didik. Penelitian ini bertujuan untuk mengetahui pengaruh implementasi pendekatan SETS terhadap kemampuan berpikir kritis peserta didik. Desain penelitian yang digunakan yaitu non-equivalent control group design. Subjek penelitian berjumlah 59 peserta didik. Teknik pengumpulan data adalah teknik tes dan nontes. Teknik tes dalam penelitian ini digunakan untuk mengukur kemampuan berpikir kritis peserta didik. Teknik non-tes berupa angket, observasi, wawancara, dan dokumentasi. Teknik analisis data menggunakan uji regresi sederhana untuk mengetahui pengaruh X (pendekatan SETS) terhadap Y (kemampuan berpikir kritis) dan uji independent sampel t-test untuk mengetahui perbedaan antara peserta didik yang belajar menggunakan pendekatan SETS dengan peserta diik yang belajar menggunakan pendekatan saintifik. Hasil penelitian menunjukan bahwa terdapat pengaruh penerapan pendekatan SETS terhadap kemampuan berpikir kritis peserta didik dengan Fhitung>Ftabel yaitu 34,12 > 4,18 ( α = 0,05), serta terdapat perbedaan hasil belajar pada kelas eksperimen sebesar 0,534 bertaraf sedang dan peningkatan pada kelas kontrol sebesar 0,42 bertaraf sedang. Hal itu berarti terdapat perbedaan antara peserta didik yang belajar menggunakan pendekatan SETS dengan peserta didik yang belajar menggunakan pendekatan saintifik.

Thematic learning is expected that learning activities can involve students actively and in learning activities, so that students get direct experience which makes learning activities much more meaningful. Thematic teaching materials with the STEM approach are an alternative to improve students' problem-solving abilities. This study aims to analyze the validity, convenience, attractiveness, usefulness, and effectiveness of thematic teaching materials with the STEM approach to improve students' problem solving abilities in elementary schools. This research is a type of Research and Development (R&D) research, the development is carried out according to the theory of Borg & Gall. The subjects in this study were determined using a purposive sampling technique and obtained as many as 20 students. The data collection tool uses valid and reliable test instruments. Validity data analysis techniques show that thematic teaching materials with the STEM approach are very valid to use. Effectiveness data analysis technique uses N-Gain with a calculation result of 0.57 with a significance of 0.01<0.05. Based on this research, it can be concluded that the thematic teaching materials with the STEM approach developed are valid and effective for improving students' problem solving abilities in elementary schools.

Pembelajaran di masa pandemi menjadikan adanya perubahan proses yang dilakukan guru dalam penerapan metode dan media pembelajaran. Penggunaan media pembelajaran daring yang masih berbasis pemberian tautan bahan ajar menjadikan pembelajarannya menjadi kurang menarik. Penggunaan teknologi yang diterapkan di masa pandemi menjadikan setiap siswa dan orang tua akan mengikuti perkembangan teknologi. Flipbook digital merupakan salah satu media bahan ajar yang berbasis teknologi yang mudah dalam pembuatan dan penggunaan menjadi salah satu alternatif penggunaan media pembelajaran di masa pandemi. Kemampuannya yang bisa digunakan pada smartphone menjadikannya sangat bisa diandalkan. Siswa tingkat sekolah dasar yang pada dasarnya menggunakan pembelajaran kontekstual dirasa tepat menggunakan bahan ajar dengan media ini. Untuk melihat seberapa efektif penggunaan flipbook digital terhadap proses pembelajaran, maka dilakukan penelitian ini dengan menggunakan pengembangan model ADDIE. Pengembangan dilakukan dengan melakukan analisis kebutuhan siswa dan guru, kemudian melakukan tahap perancangan untuk mendesain bahan ajar, kemudian melakukan pengembangan bahan ajar yang telah didesain dengan validasi oleh beberapa validator, kemudian dilakukan tahap implementasi untuk menerapkan bahan ajar ke siswa, dan terakhir dilakukan evaluasi untuk mengukur keefektivan penggunaan medianya. Hasilnya, berdasarkan uji N-Gain diperoleh skor sebesar 57,21% yang menunjukkan bahwa flipbook digital cukup efektif terhadap proses pembelajaran.

One of the reasons for the low social studies learning outcomes in class IV SD Negeri 1 Jagabaya 1 Bandar Lampung is that during the social studies learning process the teacher is less able to stimulate students to be actively involved and express ideas or the ability to think in the learning process. The aims of this research is to improve student learning outcomes. This research is a classroom action research with 25 students as respondents consisting of 12 boys and 13 girls. Data collection techniques use observation and individual tests in the form of daily tests at the end of each cycle. Based on the research results it is known that the cooperative learning model can improve student learning outcomes.