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All Journal Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) Jurnal Ilmu Pertanian Indonesia Jurnal Ilmu Tanah dan Lingkungan (Journal of Soil Science and Environment) Journal of Tropical Soils Biota: Jurnal Ilmiah Ilmu-Ilmu Hayati Jurnal Tanaman Industri dan Penyegar JTSL (Jurnal Tanah dan Sumberdaya Lahan) Journal of Degraded and Mining Lands Management MAJALAH ILMIAH GLOBE SAINS TANAH - Journal of Soil Science and Agroclimatology Caraka Tani: Journal of Sustainable Agriculture Jurnal Penelitian Kelapa Sawit Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) Jurnal Entomologi Indonesia Jurnal Tanah dan Iklim BIOVALENTIA: Biological Research Journal
Gunawan Djajakirana
Departemen Ilmu Tanah Dan Sumber Daya Lahan, Fakultas Pertanian, IPB University, Kampus IPB Darmaga Bogor 16680
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Earth & Planetary Sciences Economics, Econometrics & Finance Education Engineering Environmental Science Immunology & microbiology Industrial & Manufacturing Engineering Medicine & Pharmacology

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Slow- Release Fertilizer Formulation Using Acrylic and Chitosan Coating Handayani, Lili; Djajakirana, Gunawan; Darmawan, .; Munoz, Canecio Peralta
JOURNAL OF TROPICAL SOILS Vol. 20 No. 1: January 2015
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2015.v20i1.37-45

Abstract

The low-efficiency problem in fertilizer application can be overcome by controlling fertilizer solubility, i.e. by rendering the fertilizer to be released gradually; such material is also known as slow-release fertilizer (SRF). This research was aimed to formulate SRF by coating technique using acrylic and chitosan as the coating material, and to evaluate fertilizer resistance to too fast disintegration, and rate of nutrient release method. The results demonstrated that fertilizer formulation containing N, P, K, Fe, Cu, and Zn with granulation technique yielded 74% of granules with 2-5 mm in diameter. The SRFs (formulated fertilizer with acrylic or chitosan coating) were more resistant to water pounding than non-SRF. Furthermore, shaking test with distilled water or 2% citric acid, or by percolation test with distilled water showed that the SRFs had lower nutrient solubility than the non-SRFs. The results of shaking test also specifically indicated that coating with acrylic made the fertilizer more resistant to the citric acid,suggesting that this coating material would be more suitable in acidic soils. The SRFs formulated with the addition of chitosan during blending of micronutrients prior to mixing with macronutrients, granulation, and final coating exhibited lower nutrient solubility than the SRFs without the pre-coating chitosan addition. [How to Cite: Lili H, G Djajakirana, Darmawan, and CP Munoz. 2015. Slow- Release Fertilizer Formulation Using Acrylic and Chitosan Coating. J Trop Soils 19: 37-45. Doi: 10.5400/jts.2015.20.1.37][Permalink/DOI: www.dx.doi.org/10.5400/jts.2015.20.1.37]
The Diversity and Abundance of Springtail (Collembola) on Forests and Smallholder in Jambi Widrializa, .; Widyastuti, Rahayu; Santosa, Dwi Andreas; Djajakirana, Gunawan
JOURNAL OF TROPICAL SOILS Vol. 20 No. 3: September 2015
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2015.v20i3.173-180

Abstract

Harapan forests is the first restoration forest in Indonesia, includes several different ecosystems. Different ecosystems have different characteristic to affect the diversity and abundance of Collembola. In the ecosystem, Collembola have an important role in biocontrol, decomposition, soil nutrient distribution, stimulation of soil microbial activity and as an alternative feed for predators. This study was aimed to investigate the diversity and abundance of Collembola in four ecosystems at Harapan forest, i.e. secondary forest, rubber forest, rubber smallholder and oil palm smallholder. To achieve the objective, soil samples were taken at 48 observation points in the four ecosystem. The soil samples were then extracted by Kempson Extractor. The diversity and abundance of Collembola in four ecosystems were categorized as medium to high. The total of individual and population of Collembola in the secondary and rubber forest ecosystems were likely to be higher than in the rubber and oil palm smallholders. This study had also identified four orders, 14 families and 31 genera of Collembola, where Isotomiella and Proisotoma dominated the genus of Collembola in the four ecosystems. [How to Cite: Widrializa, R Widyastuti, DA Santosa and G Djajakirana. 2015. The Diversity and Abundance of Springtail (Collembola) on Forests and Smallholder in Jambi. J Trop Soils 20: 173-180. Doi: 10.5400/jts.2015.20.3.173] 
Laju Dekomposisi dan Hara Tersedia dari Pangkasan Tumbuhan Bawah Perkebunan Kelapa Oktariani, Putri; Suryawijaya, Putu Kevin; Djajakirana, Gunawan; Iskandar
Jurnal Ilmu Tanah dan Lingkungan Vol 27 No 2 (2025): Jurnal Ilmu Tanah dan Lingkungan
Publisher : Departemen Ilmu Tanah dan Sumberdaya Lahan, Fakultas Pertanian, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/jitl.27.2.82-87

Abstract

The implementation of organic farming in peatland coconut plantations faces challenges such as the low availability of natural nutrients, restrictions on the use of synthetic fertilizers and pesticides, and the demand for soil fertility conservation to ensure sustainable production. One potential solution is the utilization of undergrowth pruning, predominantly composed of Nephrolepis sp., as a source of organic nutrients.This study aimed to determine the decomposition rate and estimate the nutrient release potential from undergrowth pruning in a coconut plantation on peat soil in Riau Province, Indonesia. The litter bag method was employed with an observation period of eight weeks. Results showed that the decomposition rate of the pruned biomass reached 1.92 g per week, with a dry weight reduction of 68%. The most abundant nutrients released during decomposition were potassium (1.79%), phosphorus (0.07%), and copper (5.68 ppm). These findings suggest that undergrowth pruning has the potential to serve as an alternative nutrient source, supporting environmentally friendly coconut cultivation systems on peatlands.
Kelarutan Nikel Pada Campuran Tanah Berbahan Induk Ultrabasa dengan Gambut pada Kondisi Jenuh dan Tidak Jenuh Air Sumawinata, Basuki; Djajakirana, Gunawan; Simbolon, David Ricardo
Jurnal Ilmu Tanah dan Lingkungan Vol 25 No 1 (2023): Jurnal Ilmu Tanah dan Lingkungan
Publisher : Departemen Ilmu Tanah dan Sumberdaya Lahan, Fakultas Pertanian, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/jitl.25.1.25-29

Abstract

Gambut tropik dengan bobot isi yang rendah berdampak pada berkurangnya kemampuan tanah gambut dalam menopang tanaman. Untuk meningkatkan bobot isi gambut maka dilakukan pencampuran tanah mineral dengan tanah gambut. Namun sumber tanah mineral yang dekat ke lahan gambut adalah tanah berbahan induk ultrabasa dengan kandungan logam Nikel (Ni) yang tinggi mencapai 5000 ppm. Karakter lahan gambut yang asam dan berada pada topografi yang rendah menjadi dugaan akan meningkatkan kelarutan Ni saat terjadi banjir. Oleh karena itu pencampuran bahan-bahan tanah dan perlakuan air bertujuan untuk mengukur kelarutan Ni pada kesetimbangan pH setelah pencampuran dan diekstrak menggunakan larutan NH4OAc 1.0 N pH 7.0; 4.8; 4.2, HCl 1.0 N; 0.1 N, dan H2SO4 1.0 N. Kesetimbangan pH setelah pencampuran bahan tanah berada pada pH 5.2 – 6.1 yang berarti kelarutan Ni ditunjukan oleh hasil ekstrak larutan NH4OAc 1.0 N pH 7.0 - 4.8. Pada rentang kesetimbangan pH tersebut nilai kelarutan Ni pada perlakuan penjenuhan (J) dan pengeringan (K) tidak berbeda nyata pada uji taraf 5%. Namun kelarutan Ni pada setiap penambahan bobot gambut berbeda nyata pada kondisi penjenuhan yang dikeringkan sampai kondisi lembab (JK).
Isolation and Electrochemical Evaluation of Electrogenic Bacteria from the Sediment of Two Waterlogged-Ecosystems Indriyani, Yohanna Anisa; Rusmana, Iman; Anwar, Syaiful; Djajakirana, Gunawan; Santosa, Dwi Andreas
Biota : Jurnal Ilmiah Ilmu-Ilmu Hayati Vol 10, No 1 (2025): February 2025
Publisher : Universitas Atma Jaya Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24002/biota.v10i1.9476

Abstract

Electrogenic microbes have been exploited in the microbial fuel cell (MFC) system for harvesting bioelectricity. Electrogens are widely distributed in various environments, but the exploration of this microbial group from ecosystems in Indonesia is still limited. This present study aimed to isolate the electrogenic bacteria from sediments of two waterlogged ecosystems (dam and paddy field) using serial dilution into extinction method prior to streak plate method on the solid thioglycollate media supplemented with Fe3+. Electrochemical evaluation was conducted in glucose-fed dual-chamber MFC by using Arduino UNO-based data logger for the accurate monitoring of electricity production in the term of open circuit voltage (OCV). A total of 54 electrogens were successfully isolated from these two ecosystems, ranging from weakness to strongest electrogens (OCV >800 mV) and ranging from microaerophilic, aerotolerant and facultative anaerobes, to obligate anaerobes. This result also suggested that sediment of waterlogged ecosystems rich in electron donor and solid acceptor electron compounds could potentially host electrogenic microbes. The exploration of electrogens from many other waterlogged ecosystems in Indonesia, both natural and anthropic ecosystems, could be conducted to collect genetic resources of novel electrogenic bacteria for the development of MFC technology in Indonesia.
Assessing N2O Emissions from Tropical Crop Cultivation in Mineral and Peatland Soils: A Review Suwardi, Suwardi; Darmawan, Darmawan; Djajakirana, Gunawan; Sumawinata, Basuki; Al Viandari, Nourma
Caraka Tani: Journal of Sustainable Agriculture Vol 38, No 2 (2023): October
Publisher : Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/carakatani.v38i2.75235

Abstract

Nitrous oxide (N2O) emissions from agricultural activities contribute significantly to global warming. Understanding the factors influencing N2O emissions is crucial for developing effective mitigation strategies. This review assesses N2O emissions from various crops cultivated in tropical mineral and peatland soils, providing insights into the impact of land use, fertilization practices and rainfall on N2O fluxes. Field measurements of N2O fluxes were conducted in agricultural fields growing corn, peanuts, and cassava in Bogor Regency, West Java Province, as well as in peatland areas with Acacia plantations and natural primary forests in Bengkalis Regency, Riau Province. The study assesses the total N2O fluxes for each crop and land type, revealing significant variations in N2O emissions among different crops and land uses. Peatland areas exhibit higher emissions compared to mineral soils, emphasizing the need for targeted mitigation measures in these ecosystems. The findings highlight the importance of considering the type and age of land use when evaluating N2O emissions. Land management practices, such as fertilizer use and soil disturbance, emerge as critical factors affecting N2O emissions. Improper fertilizer application and excessive soil disturbance can lead to increased N2O emissions, underscoring the necessity for careful N fertilizer management and conservation tillage techniques.
Fluks Metana dan Karakteristik Tanah pada Beberapa Macam Sistem Budidaya , Suprihati; Iswandi Anas; Supiandi Sabiham; Gunawan Djajakirana
Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) Vol. 34 No. 3 (2006): Buletin Agronomi
Publisher : Indonesia Society of Agronomy (PERAGI) and Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University, Bogor, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (59.427 KB) | DOI: 10.24831/jai.v34i3.1299

Abstract

Methane (CH4) is an important greenhouse gas that has a high heat trapping capacity thus potentially contribute to the global-warming.  Agriculture is considered among the responsible emission sources of CH4. Relationship among soil characteristics, soil microbes, and CH4 flux is very important in understanding the mechanism involved in the mitigation effects of certain agriculture practices. Results of this research showed that rice field produced the highest CH4 flux (7.4976 ± 0.5299 mg CH4-C m-2 h-1, n=3), while vegetable, sweet potato, yam bean and corn cropping produced lower CH4 flux (-0.7708 ± 0.6434 to 0.4605 ± 0.5255 mg CH4-C m-2 h-1, n=3). Nitrifier population among cropping systems was 3.13x103 to 3.17x104  MPN g-1 soil (dry weight), while denitrifier population was 3.77x103 to 1.17x105 MPN g-1 soil (dry weight).  There were no specific dominance proportion of nitrosomonas, nitrobacter, denitrifier and total propagule among cropping systems. The CH4 flux had highly correlation to soil water content (r = 0.951), soil pH (r = 0.852) and soil Eh (r = -0.982). Denitrifier had significantly correlation to soil pH (r = -0.635) and soil ammonium content (r =  -0.681).   Key words :  CH4 flux, cropping system, soil characteristic, soil microbes
Co-Authors . DARMAWAN Al Viandari, Nourma Amanda Kusuma Dewi Atang Sutandi Basuki Sumawinata Darmawan Darmawan Darmawan Darmawan Darmawan Dhanti Hanifa Muslimah DWI ANDREAS SANTOSA Edwin Aprianda Eko Mapilata, Eko Erwinda Erwinda Gunawan Sutio Gusti Z. Anshari Iman Rusmana Indri Hapsari Fitriyani Indriyani, Yohanna Anisa Indriyati, Lilik Tri ISKANDAR Iskandar Iskandar Iskandar Iswandi Anas Iswandi Anas Komarsa Gandasasmita Kurnia Dewi Sasmita Laksono Trisnantoro Lili Handayani, Lili Munoz, Canecio Peralta Nur Izza Faiqotul Himmah Nuriman, Muhammad Nurul Faoziah Oktariani, Putri Putri Handayani Sijabat Qonita Qurrota A’yun RAHAYU WIDYASTUTI Riki Ruhimat Sarjiya Antonius Septiana, Liska Mutiara Simbolon, David Ricardo Siti Nurzakiah Siti Nurzakiah Sudirman Yahya Supiandi Sabiham Suprihati Suryawijaya, Putu Kevin Suwardi Suwardi Syaiful Anwar Untung Sudadi Widrializa, . Yayuk Rahayuningsih Suhardjono Yohanna Anisa Indriyani