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Purpose This study aimed to discover the precise material composition and thickness (water hyacinth, rice straw, and banana pseudostem) of organic mulch sheet. Methods This current research was conducted by means of a number of treatments with various material compositions and thickness of organic mulch sheet. Several tests were administered such as chemical analyses on organic mulch sheet, tensile strength, and Vilensky test. Result Various compositions of materials resulted in various chemical analyses of organic mulch sheet. Organic mulch with the strongest tensile strength was during the treatment of 60% water hyacinth, 20% rice straw, and 20% banana pseudostem, reaching 3.28 N/m 2 . The highest sunlight intensity of mulch composition was during the treatment of M4 (50% water hyacinth, 40% rice straw, and 10% banana pseudostem) with no hole and absorbing. Conclusion The result showed that water hyacinth, rice straw, and banana pseudostem could be used as the materials for organic mulch sheets. They could add organic matters into the soil, have endurance and strength to apply as mulch in crop cultivation, as well as help plants adapt to climate change.

The number of corn production and consumption in Indonesia has increased every year. One of the activities in achieving the production target is by supplying high-quality corn seeds. The water content of harvested sweet corn was ranging from 60% to70%. In order to produce a high quality of seeds, drying should perform with a standard drying temperature for seeds which is between 38°C and 43°C. A performance test of a tray drying machine with an air dehumidifying process was conducted. The air dehumidifying process was conducted by an air conditioning system. Drying was carried out until the corn seeds reach 10-11% moisture content with observations every two hours. This drying machine provided lower relative humidity air drying than conventional sun-drying with a 75% relative humidity reduction from the environment. Therefore, drying with optimal temperature can be conducted faster and higher efficiency. The average dehumidified air temperature was 41.1±0.6°C and the average relative humidity was 15.9±0.7% was used for drying air. It took 44 hours 25 minutes to reach 11% of sweet corn’s moisture content while the sun drying process took 89 hours of drying. The seed germination could reach 85.7% by using this method which was a 1% difference from a sun-drying method which was 86.7%.

The application of plant acoustic frequency technology (PAFT) can spur plant growth, increase productivity, immune system, quality, and extend the shelf life of agricultural products after harvest. The application of sound waves in plants can stimulate the opening of the stomata to optimally absorb nutrients and water. This study aims to determine the effect of frequency and time of PAFT exposure by utilizing Javanese gamelan traditional music on the vegetative growth of red-lettuce (Lactuca sativa var.). Javanese gamelan music used was titled Puspawarna with variations in the frequency of 3-5, 7-9, and 11-13 kHz. The variation of exposure time of sound waves was 1, 2, and 3 hours. PAFT exposure was given routinely in the morning and evening. The results of this study indicated that the best treatment was at 3-5 kHz with an exposure time of 2 hours. This treatment gave a significantly better effect when compared to plants without PAFT. The best combination of frequency and time of PAFT exposure produced 10 leaves, plant height of 9.4 cm, wet weight of 4 g, dry weight of 0.22 g, leaf area of 27.19 cm 2 , leaf red mean of 63, and stomata opening width of 145.44~206.59 µm.

ABSTRAKSektor perikanan merupakan salah satu sektor yang memiliki peran penting dalam perekonomian Indonesia, khususnya udang. Udang merupakan komoditas perikanan andalan Indonesia yang menjadi komoditas ekspor (Jenderal Perikanan, 2014). Menurut Suyanto dkk (2009), berkurangnya kualitas air tambak akibat rendahnya kadar oksigen dapat menyebabkan wabah penyakit untuk tambak udang. Selama ini, masyarakat menggunakan aerator listrik untuk meningkatkan kualitas air tambak udang, sehingga tidak hemat energi. Oleh karena itu, dibuatlah aerator dengan tenaga kincir angin. Penelitian ini dilakukan didaerah tambak Desa Wedani, Kecamatan Cerme, Kabupaten Gresik, Jawa Timur. Dimana proses pelaksanaannya dilakukan pada bulan Oktober 2017 -Februari 2018. Dari hasil pengujian yang dilakukan, diperoleh rata-rata kecepatan angin sebesar 3,16 m/s, dengan jumlah putaran kincir angin sebesar 26,64 rpm dan jumlah putaran pompa spiral sebesar 2,664 rpm. Sedangkan untuk besarnya daya angin teoritis yang diperoleh adalah 15,79 Wh dan besarnya daya angin actual adalah 9,36 Wh. Kemudian besarnya debit air rata-rata sebesar 8,42 cm3/s dengan tinggi tekannya sebesar 52,8 cm. Dari pengujian dengan DO meter, dapat diketahui bahwa aerator pompa spiral ini mampu meningkatkan kandungan oksigen terlarut sebesar 2,08 mg/L. ABSTRACTFisheries is one sector that has an important role in the Indonesia's economy, especially shrimp. Shrimp is a commodity export mainstay of Indonesia (Jenderal Perikanan, 2014). According to Suyanto dkk (2009), reduced water quality due to low oxygen levels cause disease in shrimp. So far, people use electric aerators to improve water quality of shrimp ponds. Howefer, the aerator is not energy efficient. Therefore, a windmill aerator is made on shrimp farming to obtained maximum result. The research was carried out in the pond the Village Wedani -Cerme -Gersik, East Java. Where is the implementation process to be done in October 2017 -February 2018. From the test results obtained an an average wind speeds of 3,16 m/s, with the number of turns of windmills of 26,64 rpm and the number of the rounds spiral pump 2,664 rpm. As for the amount of theoretical wind power obtained is15,79 Wh and the actual wind power obtained is 9,36 Wh. Then, the magnitude of the average water discharge of of 8,42 cm3/s with a water burst height of 52,8 cm. from testing by DO Meter, it can be seen that this spiral pump aerator can increase dissolved oxygen content of 2,08 mg/L. Kata Kunci: Aerator, Spiral Pump,The Windmill Savonius. PENDAHULUANSektor perikanan merupakan salah satu sektor yang memiliki peran penting dalam perekonomian Indonesia, terutama udang. Udang merupakan komoditas perikanan andalan Indonesia yang menjadi komoditas ekspor (Dirjen Perikanan, 2014). Luas area tambak udang di Indonesia saat ini sekitar 344.759 ha atau sekitar 39,78% dari potensi lahan yang tersedia yakni