Dragonflies have an important role for the stability of the ecosystem that is as predator and prey at the same time. The availability of food resources and optimal environmental conditions affect the species richness of dragonflies in the habitats. Reasearch on dragonfly comunity structure aims to find out the differences of community structure in each habitat type in the region of Curug Lawe Benowo. The research was conductet in 4 different stations which focus on species of dragonfly, amount of an individual species, habitats, environmental conditions, and the corellation between the variables. The method used is point count. The results showed that there are 19 dragonfly species which came from 7 different Family. The total number of individuals encountered from 4 stations is 205. The common species that can be found in all of the stations is Euphaea variegata. The level of diversity are medium, the level of evenness is fairly even. Similarity of species in any habitat types indicate that the habitats has a three kind of similarity levels that is fairly equal, less equal and not equal. Data analysis shows that there is a corellations between environmental conditions, and dragonfly species, affecting abundance and distributions of a dragonfly in the habitats, and can be used to describe dragonflies community structure in the region. Key words: Community structure, dragonfly, Curug Lawe-Benowo

Dragonflies role as a predator in an ecosystem and become a healthy aquatic bio-indicators related to the life cycle. The diversity of habitat, food and predators affect community structure dragonfly. This study aims to determine the composition and community structure dragonfly morning and afternoon as well as the relationship with the physical environmental factors on four habitat in Semirang waterfall. Research using transect Point Count method. Statistically, the biodiversity of odonata in each habitat is significantly different. The results shows there are 15 species from 10 Family in morning observations and 12 species of 6 Family in afternoon observations, with a total of 17 species of 10 family of odonata. Biodiversity in each station is low to moderately with high evenness. The highest abundance found in river habitat without the canopy during the afternoon that Vestalis luctuosa (61.29%), while the lowest abundance found in the the canopied river habitat when afternoon that is Drepanosticta spatulifera (1.33%). Common species at area of Semirang waterfall are Euphaea variegata, Orthetrum sabina and Vestalis luctuosa. Endemic species at area of Semirang waterfall are Heliocypha fenestrata, Drepanosticta spatulifera and D. sundana. Key words : Community structure, Odonata, Semirang waterfall

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Wood vinegar rice husk contains a chemical compound that can be used as a biopesticides. Wood vinegar contained compounds which estimated potential as repellent, antifeedant, antimicrobials, antioxidants, disinfectants and as preservatives. The content of chemical compounds in the wood vinegar must be identified. Identification were done by calculating the concentration of acid, phenol and an infrared spectrophotometer. Production of wood vinegar made by the pyrolysis process used pirolisator. Most of the wood vinegar obtained is evaporated using a rotary evaporator and partly extracted using the method of separating funnel. Compound of acid and phenol in wood vinegar evaporation were higher than the extraction of wood vinegar. These results were confirmed by an infrared spectrophotometer spectrum showed the functional groups of acid and phenolic compounds. Keywords: wood vinegar rice husk, acid, phenol, pyrolysis, infrared spetrofotometer

Ants potentially as predators that become natural enemies of insect pests in rice fields with paddy cultivation. This study aims to know the diversity and abundance of ants, the role of ants, the population of ants, and the influence of physical and chemical factors in organic and inorganic rice fields. The ants were collected using pit fall trap method with insect bait, fish meat, and sugar solution. The results showed that the number of species and the number of individuals in organic rice fields was higher (429 individuals, 11 species) than inorganic rice fields (193 individuals, 10 species). In general, the index of diversity in organic rice fields was higher (ranging from 0.73 to 1.65) compared to inorganic rice fields (ranging from 0 to 1.28). The index of evenness in organic rice fields ranged from 0.63 to 0.99 (evenly distributed), whereas in inorganic rice fields ranged from 0 to 0.99 (uneven until evenly distributed). The dominant ants in organic rice fields were Camponotus sp, Solenopsis geminata, Anoplolepis gracilipes, and Paratrechina longicornis, whereas in the inorganic rice fields were Tapinoma sp, Solenopsis geminata, and Camponotus sp. The index of similarity between organic and inorganic rice fields showed a high and very high degree of similarity based on the type of feed. Physical factors of high soil and air humidity environment, high soil and air temperature increased the diversity and abundance of ants in the rice fields ecosystem. Factors soil pH in accordance with the growth of soil Arthropods were neutral or slightly acidic. Chemical factors of organic matter content, Nitrogen (N), the content of C organic, and a high P total content increased the diversity and abundance of ants. Keywords: diversity and abundance, ants, organic and inorganic rice fields