Judul: Termite Diversity in Teak Stands in Tulungagung
and Wonogiri Regencies
Abstrak: Berbagai macam organisme pengganggu tanaman berpotensi dapat menyerang pohon jati termasuk rayap. Penelitian ini bertujuan untuk mengidentifikasi keanekaragaman spesies rayap pada lahan tegakan jati di Kabupaten Tulungagung dan Wonogiri. Pengambilan sampel menggunakan metode transek dengan area transek 10 m x 60 m dan pengumpanan dengan kayu pinus yang ditempatkan pada lima kecamatan di Kabupaten Tulungagung (Kalidawir, Pucanglaban, Tanggunggunung, Campur Darat, dan Ngunut) dan lima kecamatan di Wonogiri (Jatiroto, Jatisrono, Sidoharjo, Slogohimo, dan Purwantoro). Hasil penelitian menunjukkan bahwa sekurang-kurangnya ditemukan empat spesies rayap yaitu Macrotermes gilvus, Odontotermes sp., Microtermes insperatus, dan Nasutitermes havilandi. Keanekaragaman rayap di Wonogiri tergolong sedang dengan nilai H’ tertinggi (1,08), sedangkan keanekaragaman rayap di Tulungagung tergolong rendah dengan H, Various kinds of plant disrupting organisms can potentially attack teak trees including termites. This study aimed to identify the diversity of termite species in teak stands in Tulungagung and Wonogiri regencies. Sampling using the transect method with a transect area of 10 m x 60 m and feeding with pine wood placed in five sub-districts in Tulungagung Regency (Kalidawir, Pucanglaban, Tanggunggunung, Campur Darat, and Ngunut) and five sub-districts in Wonogiri (Jatiroto, Jatisrono, Sidoharjo, Slogohimo, and Purwantoro). The results showed that at least four termite species were found, Macrotermes gilvus, Odontotermes sp., Microtermes insperatus, and Nasutitermes havilandi. Termite diversity in Wonogiri was classified as medium with the highest H’ value (1.08), while termite diversity in Tulungagung was low with the lowest H’ (0.59). The dominance value of termite species in both districts was classified as medium and the evenness value in all observation locations showed an average high evenness index value. The results of the nonmetric multidimensional scalling analysis showed that Jatiroto Subdistrict and Ngunut Subdistrict have a high level of species similarity (0.90).
Keyword: keanekaragaman, rayap, pohon jati, NMDS

Judul: Subterranean Termite Attack on Tree Stands in Bogor Botanical Garden
Abstrak: Pelestarian dan perlindungan terhadap pohon-pohon yang tersimpan di Kebun Raya Bogor (KRB) perlu dilakukan untuk menghindari kerusakan oleh berbagai macam penyakit maupun serangga perusak termasuk rayap. Penelitian bertujuan menganalisis frekuensi serangan rayap dan mengidentifikasi jenis rayapnya, menganalisis preferensi rayap terhadap jenis pohon, serta tingkat kerusakan pohon akibat serangan rayap di KRB. Penelitian dilakukan dengan menggunakan metode jalur sampling. Hasil penelitian menunjukkan bahwa sebanyak 213 (100%) pohon contoh di KRB terserang rayap. Spesies rayap tanah yang ditemukan sekurang-kurangnya terdapat empat spesies yaitu Coptotermes curvignathus Holmgren, Macrotermes gilvus Hagen, Odontotermes javanicus Holmgren dan Nasutitermes matangensis Haviland. Rayap M. gilvus banyak ditemukan pada pohon Pterocarpus indicus, Dysoxilum spp., Shorea spp., dan Dimocarpus spp.. Rayap O. javanicus banyak ditemukan pada pohon Vitex cofassus, Dehaasia incrassata, Heriteria spp., dan Cordia spp.. Rayap N. matangensis banyak ditemukan pada pohon Philodendrom spp., Dysoxilum spp., dan Sindora spp.. Rayap C. curvignathus banyak ditemukan pada pohon Araucaria columnaris, Agathis sp., dan Pinus spp. Tingkat kerusakan pohon contoh akibat serangan rayap sebesar 10-90%., Preservation and protection of trees stored in the Bogor Botanical Gardens (KRB) need to be done to prevent damage by various kinds of diseases and destructive insects including termites. This study aimed to analyze the frequency of termite attacks and to identify the type of termites, to analyze termite preferences for tree species, as well as the degree of tree damage due to termite attacks in KRB. The research was conducted using the path sampling method. The results showed that as many as 213 (100%) sample trees in KRB were attacked by termites. There are at least four subterranean termite species found, namely Coptotermes curvignathus Holmgren, Macrotermes gilvus Hagen, Odontotermes javanicus Holmgren, and Nasutitermes matangensis Haviland. Termites M. gilvus are found in Pterocarpus indicus, Dysoxilum spp., Shorea spp., and Dimocarpus spp. Termites O. javanicus are found in Vitex colossus, Dehaasia incrassate, Heriteria spp., and Cordia spp. Termites N. matangensis is found in Philodendrom spp., Dysoxilum spp., and Sindora spp. Termites C. curvignathus can be found in Araucaria columnaris, Agathis sp., and Pinus spp. The level of damage to sample trees due to termite attacks is 10-90%.
Keyword: frequency, subterranean termites, termite preferences, tree healt

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition