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This study aimed to describe the differences in students' creative thinking skills in a problem-based learning model with scaffolding in the biochemistry course. This study was designed using a quantitative explanatory research design with a sample of 113 students of the Jambi University Chemistry Education Study Program. In this study, the researcher used the experimental class and control class. The sampling technique used is total sampling and purposive sampling. The research data was taken by observation, test, and interview methods. The quantitative data analysis used was the ANOVA test and continued with the Post-Hoc Scheffe’s test. The findings of this study indicate that the results of the ANOVA test indicate a significant difference in the average creative thinking results in terms of psychomotor aspects with the acquisition of significance scores of 0.000. In addition, the results of this study indicate that class A students have higher creative thinking skills than class B and class C. This is because class A students use a problem-based learning model integrated with scaffolding in their learning.

TiO2/Karbon aktif dari ampas kopi telah berhasil dilakukan. Sampel karbon aktif diuji kualitasnya dengan melakukan uji kadar air, kadar abu dan daya serap Iod yang selanjutnya dibandingkan dengan SNI (Standar Nasional Indonesia) 06-3730-1995. Uji kadar air karbon aktif ampas kopi adalah 13,8 % (SNI: maks 15%), kadar abu adalah 9,7% (SNI: maks 10%), dan daya serap Iod adalah 1.173,8 mg/g (SNI: min 750 mg/g). Ketiga uji menunjukkan bahwa kualitas karbon aktif sudah sesuai dengan SNI. Selanjutnya, TiO2/Karbon aktif dikarakterisasi dengan spektrofotometer UV-Vis untuk menentukan nilai energi gapnya dan menunjukkan hasil nilai energi gap sebesar 3 eV. Hasil FTIR (Fourier Transform Infra Red) untuk sampel karbon aktif ampas kopi menunjukkan puncak serapan C-H (2934,16 cm-1), C=C (1581,75 cm-1), C-O (1236,37 cm-1) dan C-C (580,91 cm-1) yang merupakan khas ikatan vibrasi karbon aktif. Keberadaan air juga masih dapat dilihat dengan adanya puncak serapan O-H (3674,95 cm-1). Pada sampel TiO2 murni terdapat puncak serapan milik Ti-O-Ti (600,94 cm-1 dan 493,10 cm-1) yang menunjukkan keberadaan TiO2 pada sampel. Pada sampel TiO2/Karbon aktif juga terdapat puncak serapan Ti-O-Ti (600,94 cm-1 dan 524,64 cm-1) yang menunjukkan keberadaan TiO2 didalam sampel. Lalu terdapat juga puncak serapan Ti-O-C (1505,63 cm-1) yang merupakan serapan khas dari TiO2 yang telah berikatan dengan karbon aktif. Pada hasil uji adsorpsi menunjukkan persentase degradasi yang relatif rendah yaitu untuk variasai waktu 4, 5, dan 6 jam berturut-turut adalah 28,5%, 2,71% dan 28,84%.

The material for culturing and coloring bacteria is abstract, requiring other alternatives to understand the material through a practicum in a virtual laboratory. This development research aims to produce virtual laboratory media for high school students. The media development was carried out using the ADDIE model. Media and material experts' and product validation obtained results in a very good category. The feasibility of this virtual laboratory media was practically seen through the results of the teacher's response which is in the excellent category, and the analysis of the perception of small group students is in a good category. Trials for large groups of students were performed in the two classes of MIA. The obtained result was in an excellent category, with Choen's Kappa index of 0.47 (significant 0.00), indicating a fairly strong and significant agreement on the students' responses in both classes regarding the feasibility of the developed virtual laboratory media. It can be concluded that the virtual laboratory media on culturing and coloring bacteria is feasible to be used in schools as an alternative to practicum learning media.

Intensive management practices in large-scale oil palm plantations can slow down nutrient cycling and alter other soil functions. Thus, there is a need to reduce management intensity without sacrificing productivity. The aim of our study was to investigate the effect of management practices on gross rates of soil N cycling and soil fertility. In Jambi province, Indonesia, we established a management experiment in a large-scale oil palm plantation to compare conventional practices (i.e. high fertilization rates and herbicide weeding) with reduced management intensity (i.e. reduced fertilization rates and mechanical weeding). Also, we compared the typical management zones characterizing large-scale plantations: palm circle, inter-row and frond-stacked area. After 1.5 years of this experiment, reduced and conventional management showed comparable gross soil N cycling rates; however, there were stark differences among management zones. The frond-stacked area had higher soil N cycling rates and soil fertility (high microbial biomass, extractable C, soil organic C, extractable organic N, total N and low bulk density) than inter-row and palm circle (all p ≤ 0.05). Microbial biomass was the main driver of the soil N cycle, attested by its high correlation with gross N-cycling rates (r = 0.93–0.95, p

Learning based on understanding is the result of the process of constructing knowledge, understanding and experiences of students. Materials Arthropods, especially insects and crustaceans are material close to everyday life. So that to make the learning process more interesting and motivate students and improve learning outcomes, e-LKPD teaching media is needed. The purpose of this study was to generate, determine the feasibility, and effectiveness of e-LKPD on learning outcomes. This research is a development research. This research design follows the ADDIE development model which consists of 5 stages, namely analysis, design, development, implementation and evaluation. The e-LKPD product before being tested was validated by material experts and media experts to determine the feasibility of the products made. e-LKPD Arthropoda was validated by media expert 1 with a final percentage of 87.75%, media expert 2 by 90,91% and material expert 94.31% very good category. Thus the e-LKPD product is said to be feasible. This product was then tested at SMAN 11 Muaro Jambi involving 2 biology subject teachers, a small group, 6 students, a large group of 20 students. The test results on teachers get a percentage of 89.37%. The results of small group trials get a percentage of 87.92%, large group trials get a percentage of 86.69% including the very good category. The use of Constructivism-based Arthropoda e-LKPD is effective in improving student learning outcomes. Key words: Arthropod,e-LKPD, Construtivism Abstrak Program Studi Pendidikan Biologi FKIP Universitas Jambi, Jambi- Indonesia Pembelajaran berdasarkan pada pemahaman ialah hasil dari proses konstruksi pengetahuan, pemahaman dan pengalaman peserta didik. Materi Arthropoda khususnya insecta dan crustacea merupakan materi dekat dengan kehidupan sehari-hari. Sehingga untuk membuat proses pembelajaran menjadi lebih menarik minat dan motivasi peserta didik serta meningkatkan hasil belajar maka diperlukan media ajar e-LKPD. Tujuan penelitian ini adalah menghasilkan, mengetahui kelayakan, dan efektifitas e-LKPD terhadap hasil belajar. Penelitian ini merupakan penelitian pengembangan. Desain penelitian ini mengikuti model pengembangan ADDIE yang terdiri 5 tahap yaitu analisis, desain, pengembangan, implementasi dan evaluasi. Produk e-LKPD sebelum diujicobakan divalidasi oleh ahli materi dan ahli media untuk mengetahui kelayakan dari produk yang dibuat. e-LKPD Arthropoda divalidasi oleh ahli media 1 dengan persentase akhir 87,75%, ahli media 2 sebesar 90,91% dan ahli materi sebesar 94,31% kategori sangat baik. Dengan demikian produk e-LKPD dikatakan layak. Produk ini kemudian di ujicobakan di SMAN 11 Muaro Jambi melibatkan 2 orang guru mata pelajaran biologi, kelompok kecil, 6 orang peserta didik, kelompok besar 20 orang peserta didik. Hasil ujicoba pada guru mendapatkan persentase 89,37%. Hasil ujicoba kelompok kecil mendapatkan persentase 87,92%, ujicoba kelompok besar mendapatkan persentase 86,69% termasuk kategori sangat baik. Penggunaan e-LKPD Arthropoda berbasis Konstruktivisme efektif meningkatkan hasil belajar peserta didik. Kata kunci: Arthropoda, E-LKPD, Konstruktivisme

Conventional intensive management, such as high fertilizer and herbicide applications, are common practice in large-scale oil palm plantations. One of the proposed solutions to lessen its environmental impact is to reduce fertilization and employ mechanical weeding without sacrificing yield and profit. A full factorial experiment with two fertilization rates (260 N, 50 P, 220 K kg ha-1 yr-1 as conventional practice, and 136 N, 17 P, 187 K kg ha-1 yr-1, equal to harvest export, as reduced management) and two weeding methods (conventional herbicide application, and mechanical weeding as reduced management) was established in 2016 at a large-scale oil palm plantation (planted in 1998-2002) on a sandy clay loam Acrisol soil in Jambi, Indonesia. Soil CO2, N2O, and CH4 fluxes were measured monthly from July 2019 to June 2020, using vented static chambers. At each plot, the measurements were conducted on two randomly selected subplots, and in each subplot, we measured at three management zones (palm circle, inter-row, and frond-stacked area). During 2017-2020, fruit yield did not differ among treatments (fertilization: P=0.35; weeding control: P=0.11). Soil CO2, N2O, and CH4 fluxes also did not differ among treatments (fertilization: P>0.81; weeding control: P>0.28). Area-weighted from the three management zones, soil CO2 fluxes (mg C m-2 h-1) were 61±2 for conventional and 65±4 for reduced fertilization and 64±4 for herbicide and 62±2 for mechanical weeding. Soil N2O fluxes (µg N m-2 h-1) were 46±12 for conventional and 45±16 for reduced fertilization and 57±15 for herbicide and 34±12 for mechanical weeding. Soil CH4 fluxes (µg C m-2 h-1) were -17±2 for conventional and -17±3 for reduced fertilization and -17±3 for herbicide and -17±2 for mechanical weeding. Distinct differences were observed among the three management zones. Frond-stacked area, with high soil organic carbon and low soil bulk density, had the highest soil CO2 emission and soil CH4 uptake (P≤0.01). Palm circle, with fertilizer application and high soil bulk density, had the highest soil N2O emission and lowest soil CH4 uptake (P≤0.01). Inter-row area, with low soil organic carbon and no direct fertilizer application, had the lowest soil CO2 and N2O emission (P≤0.01). Soil CO2 (rho=0.64, P≤0.05) and N2O (rho=0.53, P≤0.05) fluxes were positively correlated with total mineral N. Soil CH4 flux was negatively correlated with total mineral N (rho=-0.30, P≤0.05) and positively correlated with water-filled pore space (rho=0.66, P≤0.05). Although the frond-stacked area only accounted for 15% of the oil palm plantation area, it contributed 30% of soil CO2 emission and 41% of soil CH4 uptake. The palm circle accounted for 18% of the oil palm plantation area and contributed 79% of soil N2O emissions. Our results indicated that the inherent management zones in oil palm plantations should be spatially represented for accurate quantification of soil greenhouse gas fluxes. Our findings showed that reduced management maintained yield whereas soil greenhouse gas fluxes remained high at least during the 3-4 years of this management experiment, which signified the legacy effect of more than a decade-long conventional management in this mature oil palm plantation.

Media is one of the essential components in learning to reach the highest learning outcomes. Therefore, teachers should create and utilize media in every learning process. This study aimed to develop ane-practicum manual based on guided inquiry class material for grade VII students of junior high school. The manual was developed using the ADDIE development model (Analysis, Design, Development, Implementation, and Evaluation). Data were collected using questionnaire of media experts, material experts, and teacher and student perception questionnaires. This research was conducted at state junior high school 2 Jujuhan Bungo Regency Jambi Province. This study shows that the instructional e-practicum manual based on inquiry is considered interesting and suitable for learning.

Udara merupakan faktor yang penting dalam hidup dan kehidupan. Emisi dari berbagai gas dan partikel dari kegiatan transportasi kedalam atmosfer menimbulkan berbagai problem menurunnya mutu lingkungan. Pada umumnya pertambahan jumlah kendaraan, jika tidak dilakukannya upaya pengelolaan lingkungan akan mengakibatkan pertambahan pula dampak lingkungan yang negatif. Pertambahan volume lalu lintas juga akan mengakibatkan bertambahnya emisi polusi udara sehingga dapat menurunkan kualitas udara. Salah satunya polutan gas CO (Karbon Dioksida) dan PM10 yang menjadi kontributor polusi udara. Prediksi terhadap sebaran gas CO dan PM10 perlu dilakukan untuk melihat arah sebaran serta daerah-daerah yang berpotensi terdampak gas CO dan PM10. Hysplit merupakan model yang dapat memprediksi sebaran polutan yang menghubungkan polutan dengan komponen meteorologi di suatu tempat. Tujuan penelitian ini adalah memetakan sebaran CO dan PM10 di 3 lokasi penelitian di Kota Jambi, menganalisis sebaran gas CO dan PM10 di 3 lokasi penelitian di Kota Jambi dan menentukan lokasi-lokasi yang berpotensi terpapar maksimum. Penelitian ini dilakukan di Kota Jambi berada di 3 kecamatan yaitu Jalan H. Agus Salim (depan kantor Dinas Kesehatan Kota Jambi) Kelurahan Handil Jaya Kecamatan Jelutung, Jalan HOS Cokroaminoto (depan Dealer Suzuki Mobil) Kelurahan Payo Lebar kecamatan Jelutung, dan Jalan Slamet Riyadi (Depan Kantor BPJS Ketenagakerjaan) Kelurahan Murni Kecamatan Danau Sipin. Dalam penelitian ini pengukuran CO dan PM10 dilakukan dari setiap lokasi yang ditentukan melalui program Evaluasi Kualitas Udara Perkotaan (EKUP) Kota Jambi, yang kemudian dianalisis sebarannya menggunakan model Hysplit Version 5. Sebaran yang dihasilkan menunjukkan arah CO dan PM10 dominan menuju Utara, barat laut. Analisis model Hysplit Version 5 menunjukkan kecamatan Jelutung terpapar maksimum.

Danau Kerinci di Kabupaten Kerinci Provinsi Jambi merupakan salah satu dari 15 (lima belas) danau prioritas nasional yang disepakati pada Konferensi Nasional Danau Indonesia I Tahun 2009 tentang Pengelolaan Danau Berkelanjutan. Perlindungan kerusakan ekosistem Danau Kerinci termasuk salah satu isu prioritas lingkungan hidup daerah Kabupaten Kerinci Tahun 2018. Pengelolaan Danau Kerinci diharapkan berkelanjutan untuk mempertahankan, melestarikan dan memulihkan fungsi danau berdasarkan prinsip keseimbangan ekosistem. Tujuan penelitian ini adalah menganalisis status keberlanjutan dan atribut sensitif dari pengelolaan Danau Kerinci. Penelitian menggunakan data primer melalui kuesioner, wawancara dan pengamatan lapangan serta data sekunder berupa data dan laporan pendukung. Dimensi yang digunakan untuk menilai status keberlanjutan adalah dimensi ekologi, dimensi ekonomi, dan dimensi sosial budaya dengan 29 atribut, dan dianalisis dengan metode Multi Dimensional Scaling (MDS) menggunakan program Rap-Lake yang merupakan modifikasi dari program Rapfish. Berdasarkan simulasi program Rap-Lake untuk ketiga dimensi keberlanjutan maka indeks keberlanjutan pengelolaan Danau Kerinci adalah 71,89 dengan status cukup berkelanjutan. Atribut sensitif tertinggi atau yang paling berpengaruh sebagai faktor pengungkit terbesar terhadap keberlanjutan dimensi ekologi yaitu perubahan tutupan lahan, tingkat erosi dan kualitas perairan danau. Atribut sensitif dimensi ekonomi yaitu pengendalian sedimentasi di danau, alat monitoring kualitas air, dan penguasaan teknologi. Atribut sensitif pengungkit dimensi sosial budaya yaitu Perda pengelolaan danau, tekanan penduduk terhadap lahan dan kearifan lokal. Kata kunci : Keberlanjutan, Danau Kerinci, MDS, Rap-Lake

Model project based learning berbasis STEAM adalah model yang menuntut siswa untuk menghasilkan sesuah produk, dan produk yang dihasilkan memiliki kreteria science, technology, engineering, arts dan mathematic. Tujuan penenilian adalah untuk melihat perbedaan kemampuan berpikir kreatifitas siswa menggunakan model project based learning berbasis STEAM pada materi asam dan basa. Desain penelitian ini adalah pre-experimental desain dengan jenis penelitian one-group pretest-postest desain menggunakan sampel penelitian rondom sampling. Adapun sampel yang dipilih hanya satu kelas yaitu kelas XI MIA 2. Instrument penelitian berupa rencana pelaksanaan pembelajaran, soal pretest dan posttest. Analisis data menggunakan uji paired sampel t-test, nilai rata-rata pretest 1,58 dan posttest 3,17. Hasil korelasi nilai pretest-postest 0,263 > 0,05 artinya tidak terdapat hubungan antar nilai pretest-postest. Nilai signifikansi 2- tailed 0,000 < 0,05, maka dapat disimpulkan terdapat perbedaaan yang nyata kemampuan berpikir kreatif siswa pada data pretest dan posttes. Berdasarkan hasil penelitian dapat disimpulkan terdapat perbedaan yang nyata kemampuan berpikir kreatif siswa dangan penggunaan model poreject basd learning pada materi asam dan basa di SMAN 11 Kota Jambi. Kata kunci : Model Project Based Learning, STEAM, Berpiki Kreatif ABSTRAK The STEAM-based project based learning model is a model that requires students to produce a product, and the products produced have criteria for science, technology, engineering, arts and mathematic. The aim of the study was to see differences in students' creative thinking abilities using STEAM-based project based learning models on acidic and basic material. The design of this study was pre-experimental design with the type of one-group pretest-posttest research using a sample sampling method. The sample chosen was only one class, namely class XI MIA 2. The research instrument was in the form of a learning implementation plan, about the pretest and posttest. Data analysis using paired sample t-test, pretest average value 1.58 and posttest 3.17. Corlation results of the pretest-posttest value 0.263> 0.05 means that there is no relationship between the values ​​of the pretest-posttest. 2- tailed significance value 0,000

Limbah industri tahu dapat menimbulkan pencemaran yang cukup berat karena mengandung polutan organik yang cukup tinggi, jika langsung dibuang ke badan air, maka akan menurunkan daya dukung lingkungan. Sehingga industri tahu memerlukan suatu pengolahan limbah yang bertujuan untuk mengurangi resiko beban pencemaran yang ada. Metode yang dapat diterapkan yaitu dengan memanfaatkan media tumbuhan yang merupakan salah satu metode yang cukup sederhana dan ramah lingkungan. Adapun jenis tumbuhan yang digunakan yaitu Hydrilla verticillata yang merupakan tanaman air. Pengolahan limbah menggunakan tanaman sebagai media penyerap limbah disebut juga dengan metode biofiltrasi. Penelitian ini bertujuan untuk mengetahui pengaruh Hydrilla verticillata terhadap parameter BOD, COD, dan pH. Selain itu, penelitian ini juga bertujuan untuk menentukan perlakuan terbaik yang memberikan pengaruh signifikan terhadap kadar BOD, COD, dan pH pada limbah cair tahu. Rancangan percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) faktorial dengan dua faktor, yaitu : perbedaan jumlah tanam Hydrilla verticillata dan perbedaan konsentrasi limbah cair tahu. Sampel yang diambil dalam penelitian ini adalah limbah cair industri tahu yang berlokasi di Bagan Pete Kecamatan Alam Barajo. Sedangkan tanaman yang digunakan yaitu Hydrilla verticillata yang diambil di kawasan muaro sebo, kabupaten Muaro jambi. Metode yang digunakan dalam pengambilan sampel adalah teknik purposive sampling,. Hasil Penelitian pemberian perlakuan Hydrilla verticillata dengan konsentrasi limbah cair tahu mempengaruhi karakteristik limbah cair tahu yang ditunjukkan pada pengamatan BOD, COD, dan pH. Secara umum perlakuan terbaik yaitu pada perlakuan P1K1 (Hydrilla 200g ; 1% konsentrasi limbah tahu) dibandingkan dengan perlakuan lainnya, dengan kandungan BOD dan COD terendah serta pH bersifat netral.

Chemical learning that is boring and unattractive makes students less interested in learning. For that developed multimedia learning by using software Swish Max 4. The purpose of this study was to develop multimedia learning using Swish Max 4 on radioactive and to know its impact on the learning experience of students at class XII IPA SMA N 8 Kota Jambi. This study is a development study that adapts the ADDIE model. Stage in the development research are analysis, design, development and evaluation. Instrument sheets used collecting data were questionnaire of student needs, media validation questionnaire,material validation questionnaire, teacher assessment questionnaire and students response questionnaire. The main result of this study is a multimedia learning on radioactive using Swish Max 4, that equipped with video and animation. This multimedia learning on radioactive is good based on validation results from media experts and material experts. From the results of product trials of chemistry teachers and students response at Class XII IPA SMA N 8 Jambi, this media can be used to help students in learning independently. Based on the results of study concluded that multimedia learning on radioactive using Swish Max 4 is good for use in learning and get student response to multimedia learning is very good with score 82,4%.

Progressive conversion of tropical rainforests to agricultural monocultures in South East Asia increasingly affects landscape types such as riparian areas. The impacts of conversions on soil organic matter (SOM) vary with changing landforms. However, this was often not accounted for in previous studies where SOM in soils in riparian areas was combined with SOM from well-drained adjacent slopes. Because riparian areas have a high carbon (C) storage potential, our objectives were i) to assess their C stocks after conversion to rubber and oil palm plantations in Sumatra (Indonesia) and ii) to compare the impacts of land use conversion on C stocks between riparian and well-drained areas. Average soil C stock losses from the top 30 cm were about 14% and 4% following conversion of riparian forest to rubber and oil palm plantations, respectively, indicating a high resistance of C to mineralization. C losses from well-drained areas were twice as high as from riparian areas after the respective conversion. δ13C values from riparian areas showed clear heterogeneity down soil profiles that was explained i) by alternating oxic and anoxic conditions, leading to reduced SOM and litter decomposition in riparian areas and ii) by mineral sediments and organic matter deposition and accumulation by erosion from adjacent slopes covered by plantations. We conclude that riparian areas are more resilient in terms of soil C storage towards land-use change than well-drained areas because of sediment deposition and reduced oxygen availability. On this basis, we developed a conceptual model of the effects of land-use change and various ecotone characteristics on SOM mineralization in the top- and subsoil of riparian areas.

Tropical regions, such as Sumatra, experiencing extensive transformation of natural ecosystems, are close to complete exhaustion of available land. Agroecosystems strongly modify water and nutrient cycles, leading to losses of soil fertility, C sequestration and biodiversity. Although large companies are the main drivers of deforestation and plantation establishment, smallholders account for 40% of the oil palm and the majority of the rubber production in Indonesia. Here, we assess the extent and mechanisms of soil degradation under smallholder oil palm and rubber plantations in a context of land scarcity. The topsoil properties (C and N contents, C stocks, C/N ratio, bulk density) in 207 oil palm and rubber plantations in the Jambi province of Sumatra were determined beside trees, inside rows and interrows. Soils under oil palms were on average more degraded than under rubber, showing lower C content and stocks, lower N and higher bulk density. While soil properties were homogenous under rubber, two opposite trends were observed under oil palm plantations: the majority of soils had C content 9% C. This resulted from the establishment of oil palms under conditions of land scarcity. Because the oil palm boom started when rubber was already well-established, oil palms were frequently planted in marginal areas, such as peatlands or riparian areas (high C) or soils degraded by previous use (low C). The management of oil palms led to subsequent soil degradation, especially in interrows: C content decreased and bulk density increased in older oil palm plantations. This was not observed in rubber plantations because of a C input from leaf litter spread homogeneously all over the plantation, higher ground cover and a limited use of motorized vehicles. Considering that 10% of soils under oil palms had very low C content (

Students’ cognitive engagement in teaching and learning process is an important factor for successful learning. Improvement of students’cognitive engagement was investigated through a teaching and learning process using POE (predict-observe-explain) approach and self-developed interactive media. The objective of this study is to improve students’ cognitive engagement in teaching and learning process at junior high school. The development of interactive multimedia uses Animate CC and Four D and its validation were explained. The self-developed interactive multimedia was used with POE approachin teaching and learning process at junior high school. This three steps predict-observe-explain approach is used and students higher order thinking and total participants showing higher order thinking characteritics were analysed. It was found that the self-developed interactive multimedia isto contribute to the students’ active cognitive engagement.

Indonesia lost more tropical forest than all of Brazil in 2012, mainly driven by the rubber, oil palm, and timber industries. Nonetheless, the effects of converting forest to oil palm and rubber plantations on soil organic carbon (SOC) stocks remain unclear. We analyzed SOC losses after lowland rainforest conversion to oil palm, intensive rubber, and extensive rubber plantations in Jambi Province on Sumatra Island. The focus was on two processes: (1) erosion and (2) decomposition of soil organic matter. Carbon contents in the Ah horizon under oil palm and rubber plantations were strongly reduced up to 70% and 62%, respectively. The decrease was lower under extensive rubber plantations (41%). On average, converting forest to plantations led to a loss of 10 Mg C ha(-1) after about 15 years of conversion. The C content in the subsoil was similar under the forest and the plantations. We therefore assumed that a shift to higher δ(13) C values in plantation subsoil corresponds to the losses from the upper soil layer by erosion. Erosion was estimated by comparing the δ(13) C profiles in the soils under forest and under plantations. The estimated erosion was the strongest in oil palm (35 ± 8 cm) and rubber (33 ± 10 cm) plantations. The (13) C enrichment of SOC used as a proxy of its turnover indicates a decrease of SOC decomposition rate in the Ah horizon under oil palm plantations after forest conversion. Nonetheless, based on the lack of C input from litter, we expect further losses of SOC in oil palm plantations, which are a less sustainable land use compared to rubber plantations. We conclude that δ(13) C depth profiles may be a powerful tool to disentangle soil erosion and SOC mineralization after the conversion of natural ecosystems conversion to intensive plantations when soils show gradual increase of δ(13) C values with depth.

This research is descriptive qualitative research. the purpose of this research is to analyse the pedagogical content knowledge of science’s teachers SMA Negeri 11 Kota Jambi, by using purposive sampling technique consist of nine teachers, they are two chemistry teachers, three biology teachers, three mathematics teachers and one physic teacher ware taken as a research subject are categorized as experienced, teachers who are competent in their field base on their educational background. Data collection was conducted a questionnaires reseach instruments by using a Likert scale measurement, then followed by interviews to a mathematics teacher, a physic teacher, a biology teacher and a chemistry teacher which is reinforced by chech of documents and field observations. The result showed that teacher’s knowledge of pedagogical content knowledge still low, it can be seen from the seven aspects of PCK teachers only four aspects that can be mastered by the teacher, they are knowledge learning strategies, knowledge of the subject matter and education learning, knowledge of communication with learners and knowledge of assessment and evaluation. three of PCK teachers who still don’t understand yet are knowledge of learners and their characteristics, knowledge of curriculum development and knowledge of potential learners development.

Difficulty learning abstract consepts in material forms of the molecule based on the theory of electron domain and molecular hybridization in the formation of simple covalent coumpounds involving electron is verry small in size. With conventional learning to use the media shaped balloons and images/charta make their experience misconceptions. Make use of computer assisted animations media adobeflash program. The program is able to help students discover and explore the concepts of learning materials to animate the process of formation of the molecules of the compound geometry. The program is easy to obtain and can be used on all computers. Material forms of molecules according to VSEPR theory (valence shell electron pair repulsion) and Hybridization theory contained in the computer based media is aimed at helping students learn to achieve mastery of core competencies which are already contained in the syllabus set by time. Products are developed in accordance with the educational technology area abstract include students in determining the geometry of the steps forming the molecules of the compound. The stages are carried out in the development of media, namely: design learning, create computer based animation media, validate products with product testing. Advice of expert material/content, media expert, design expert, and data from trials of the target group to be enter performance improvement products. Based on the results of the expert validation and testing of the target group can be concluded that the computer –based instructional media products on the molecular forms of material at Senior High School chemistry in particular at ninth grade IPA (Natural Sciences). With regard to these results the school, especially Senior High School 8 Batanghari media products in order to incorporate this learning into the school website that can be accessed by the wider media users for further development. Keyword: Development, Computer based Media, Molecular Forms.

The purpose of this study is to prove the existence of the learning effect of Contextual Teaching and Learning (CTL) strategy and the Self-Concept Toward Understanding Math Concepts Grade VIII MTs of Bangko. This research is the quantitative research, that’s the quasi-experimental. Data collection instruments such as questionnaires and tests the concept of self-understanding mathematical concepts. The research result are: (1) There is the influence of contextual teaching and learning strategies for understanding mathematical concepts. (2) There is the influence of self-concept to the understanding of mathematical concepts. (3) There were no effects of contextual teaching and learning strategies for understanding mathematical concepts to students who have a high self- concept. (4) There were no effects of contextual teaching and learning strategies for understanding mathematical concepts to students who have a low self-concept. (5) There is no interaction between learning strategy and self-concept. In this study it was found that CTL and self-concept in learning influence students' understanding of mathematical concepts, but CTL has a powerful role in increasing the understanding of mathematical concepts, regardless of whether the student is a high or low self-concept. Keyword: Contextual Teaching and Learning (CTL) Strategy, Self-Concept, and Understanding of Mathematical Concepts.

Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia, and is expected to continue in the next decades. Our study aimed to (1) quantify changes in soil CO2 and CH4 fluxes with land-use change and (2) determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. In each landscape, we investigated the reference land-use types (forest and secondary forest with regenerating rubber) and the converted land-use types (rubber, 7–17 years old, and oil palm plantations, 9–16 years old). We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land-use types were correlated with soil fertility: low extractable phosphorus (P) coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P < 0.05). Soil CO2 fluxes from the oil palm (107.2 to 115.7 mg C m−2 h−1) decreased compared to the other land-use types (between 178.7 and 195.9 mg C m−2 h−1; P < 0.01). Across land-use types, annual CO2 fluxes were positively correlated with soil organic carbon (C) and negatively correlated with 15N signatures, extractable P and base saturation. This suggests that the reduced soil CO2 fluxes from oil palm were the result of strongly decomposed soil organic matter and reduced soil C stocks due to reduced litter input as well as being due to a possible reduction in C allocation to roots due to improved soil fertility from liming and P fertilization in these plantations. Soil CH4 uptake in the reference land-use types was negatively correlated with net nitrogen (N) mineralization and soil mineral N, suggesting N limitation of CH4 uptake, and positively correlated with exchangeable aluminum (Al), indicating a decrease in methanotrophic activity at high Al saturation. Reduction in soil CH4 uptake in the converted land-use types (ranging from −3.0 to −14.9 μg C m−2 h−1) compared to the reference land-use types (ranging from −20.8 to −40.3 μg C m−2 h−1; P < 0.01) was due to a decrease in soil N availability in the converted land-use types. Our study shows for the first time that differences in soil fertility control the soil–atmosphere exchange of CO2 and CH4 in a tropical landscape, a mechanism that we were able to detect by conducting this study on the landscape scale.

This is a study of the attitudes and perceptions of students and teachers towards e-learning in some schools in the city of Jambi. Information in the form of knowledge attitudes and perceptions of students and teachers towards e-learning becomes an input for teachers in a lesson plan. With the approach combined methods of research sequential-explanatory model of the phase I study design using quantitative methods to answer the problem formulation, and phase II testing hypotheses using qualitative methods to establish, expand and deepen the results of quantitative research methods. The total population of 1,661 people, and 175 students are samples obtained by random and representative for purposive quantitative methods to qualitative methods, and teachers sampled 37 of the 48 people.Quantitative data collected through filling questionnaire and qualitative data by interview and observation, descriptive analysis results obtained variable values Student Attitudes (SS) = 78.3%, variables Student Perceptions (PS) = 78.4% and variable E-learning (EL) = 78.3% and each variable in both categories. For teacher sample of from descriptive analysis values variable Teacher Attitudes (SG) = 79.4%, variable Teacher Perceptions (PG) = 79.8% and variable EL = 78.7% and each variable in both categories. Overall attitudes and perceptions of students and teachers towards e-learning in science teaching is good.

Macroscopic and symbolic representation used in chemistry instruction to represent chemical changes are unable to visualize chemical changes that occur at atomic and molecular level. The purpose of this study is to develop interactive multimedia to enhance of macroscopic and symbolic representation by providing submicroscopic representation of electrolyte and non electrolyte solutions. The media was developed by using Adobe Flash and validated by experts and used for trial in small and large groups of students before the final product was being used in a real classroom teaching based on Computer Model approach. Providing submicroscopic representation attracts student’s attentions and retention in studying the teaching materials and potentially improves student’s understanding and achievement.

The purpose of this study was to develop a multimedia learning to improve student motivation and outcomes in studying chemical equilibrium. Development of interactive multimedia development model is adapted from Lee and Owens, the steps were analysis, design, development, implementation, and evaluation. The Media developed combined texts, animations, videos, references, summaries, profiles, pictures and narration to visualization abstract concepts of chemical equilibrium. After validation and trials at small group the media was used in a teaching class. It shoved that the media may be helpful for low motivations students in studying chemical equilibrium and improved students achievement.

This study was aimed at developing listening material and teaching aid. The teaching aid makes use of computer. The purpose of using computer to help students in order to make the teaching-learning process effective and interesting. In constructing or developing the thesis, R & D method is applied. This method consists of 1) assessing to identify goal, 2) conducting instructional analysis, 3) analyzing learners and contexts, 4) writing performance objective, 5) developing assessment instruments, 6) developing instructional strategy, 7) developing and select instructional materials, 8) designing and conducting formative evaluation of instruction, 9) revising instruction, and 10) designing and conducting summative evaluation. The result of the developmental study shows that the teaching aid is good. It gets 3,75. The students who are involved in this study is the students of vocational high school grade X of tourism program. All of them enjoyed the lesson. It can be concluded that the listening material and teaching aid is effective and hence it is easy to be operated. Keyword: listening material, and teaching aid

The binding of arsenic in sediments of the heavily industrialised Port Kembla Harbour, NSW, Australia, has been investigated. Both dredge and core samples have been used to develop a sieving/sequential extraction (SE) procedure. Dredge samples included oxic surficial and deeper anoxic sediment. The main core sample analysed was 18 cm deep, sliced at 2 cm intervals. Sediment was sieved to three size ranges (63 microm, 63-250 microm,250 microm) and each of these was then subjected to a four step SE, sequentially solubilizing arsenic as ion exchangeable, 1 M HCl soluble, NH(2)OH.HCl soluble, and strong oxidising acid soluble. Concentrations of 50-500 mg As kg(-1) were found, elevated well above local background values. The core sample showed elevated concentrations of arsenic within the top 6-8 cm (300-500 mg As kg(-1)), relative to the deeper sediment (100-200 mg As kg(-1)). Substantial portions of the total arsenic present in the 0-8 cm sediments of core and dredge samples, were found to be soluble in 1 M pH 5 phosphate buffer or 1 M HCl. Arsenic in the lower 8-18 cm of the core displayed different solubility, the fourth stage SE strong acid digestion being required to solubilize90% of the deep sediment arsenic. It appears that diagenesis had resulted in remobilisation of weakly bound arsenic with subsequent diffusion and deposition in surficial layers. Strong acid soluble arsenic present in deeper sediments has two possible origins: sedimented as strongly bound remaining untouched by diagenetic events, or subjected to diagenetic reactions such as pyritization, which lead to more stable crystalline forms of minerals.