Physical methods for soil disinfestation in intensive agriculture: Old methods and new approaches

Physical soil disinfestation is worldwide mainly applied in protected cropping systems or in small-scale intensive field crops. Continuous cropping of monocultures or different host plants for the same pest or pathogen often leads to heavily infested soils which forces growers to disinfest the soil thoroughly. The oldest method is steam sterilization which is applied for more than a century. In the 1970s hot water treatment of soils was developed in Japan. Hot water is applied to the soil surface to raise soil temperatures to lethal levels. Since the 1980s inundation became a new method in the Netherlands and is applied in bulb cultures. This so-called flooding of soils creates anaerobic soil conditions in which toxic compounds like greenhouse gases are produced. A new approach in soil disinfestation in the current century is hot air treatment which is developed in Israel. The method is based on blowing extremely hot air into soil particles which are thrown above soil surface into a heat chamber by a rotary spading device. In the Netherlands renewed interest has started in radiation of soil with micro waves. Radiation of soil or other substrates has been studied for decades. The mechanism is that the heat produced by radiation is lethal to pathogens and pests. Anaerobic soil disinfestation (ASD) with incorporation of fresh organic matter in soil is a method developed in the Netherlands. A new and promising Dutch development in ASD is the application of defined products. Advantages and disadvantages of all methods are presented in this paper

Perspectives of Anaerobic Soil Disinfestation

Biological soil disinfestation is an environmentally friendly method to disinfest soil. From now on we refer to it as anaerobic soil disinfestation (ASD). With ASD a green manure crop (40 t/ha) is homogeneously incorporated into the topsoil (0-30 cm) after which the field is lightly compacted and irrigated. Subsequently the field is mechanically covered with air tight virtually impermeable film (VIF) to restrict oxygen supply to the topsoil. The soil is left covered for six weeks in the summer. In this period anaerobic conditions develop rapidly in which toxic fermentation products are formed. These conditions are responsible for elimination of fungal and bacterial pathogens as well as parasitic nematodes, insects and weeds. In the Netherlands since 2004 anaerobic soil disinfestation (ASD) was applied on approximately 70 ha mainly for asparagus and strawberry runners production. When the asparagus crop was replanted ASD proved to be profitable for many years by controlling Fusarium oxysporum. Although highly effective against soilborne pathogens and pests ASD is not applied widely in the Netherlands due to the high costs of about € 4000 per ha. Apart from the costs this technique needs special attention to prevent plastic damage. Moreover the mechanism behind ASD is not well defined which makes recommendations for growers complex. A new and promising development in ASD is the application of defined products on a basis of mixtures of carbon hydrates and proteins. The mechanism of ASD will be studied in the next few years with some of these products by measuring gases and fatty acids and microbial shifts in relation to efficacy. Chemical soil disinfestation with fumigants is restricted more and more and a non-chemical approach of soil disinfestation like ASD is urgently neede

PENGENALAN KARAKTER HURUF HIJAIYAH MENGGUNAKAN METODE MODIFIED DIRECTION FEATURE (MDF) DAN METODE LEARNING VECTOR QUANTIZATION 3 (LVQ 3)

Salah satu huruf yang memiliki karakteristik unik adalah huruf Hijaiyah. Karakteristik dari huruf Hijaiyah dapat berubah berdasarkan peletakkan huruf tunggal di awal, tengah dan akhir kata. Cara lain untuk mengenali karakter huruf Hijaiyah selain dengan memperhatikan karakteristik masing-masing huruf adalah dengan memanfaatkan pengenalan pola dan jaringan syaraf tiruan. Dalam penelitian ini, proses ektraksi ciri yang digunakan adalah metode Modified Direction Feature (MDF) dan proses klasifikasi yang digunakan metode Learning Vector Quantization 3 (LVQ 3). Pengujian yang dilakukan yaitu: pengujian ukuran matriks citra yang terdiri dari 80x80 piksel, 100x100 piksel, dan 120x120 piksel; dan pegujian nilailearning rate 0.01, 0.03,0.05, dan 0.07. Dari hasil pengujian yang dilakukan adalah sistem mampu mengenali pola karakter Huruf Hijaiyah dengan akurasi terbaik adalah 82.44% pada matriks citra berukuran 120x120 piksel dengan learning rate 0.03. Kata Kunci: Huruf Hijaiyah, Pengenalan Pola, Modofied Direction Feature, Learning Vector Quantizatio

Perbedaan Penurunan Kadar BOD5 dan COD dengan Pemberian Berbagai Dosis Urine Sapi Fermentasi dan Variasi Waktu Tinggal pada Limbah Cair PT. Sinar Sosro Ungaran

PT. Sinar Sosro Ungaran merupakan industri pangan yang memproduksi minuman teh botol dengan kapasitas produksi sebesar 200.000 liter per hari. Waste Water treatment merupakan unit pengolahan air limbah yang didirikan untuk mengolah air sisa produksi dan kegiatan pabrik sehingga dapat dibuang ke badan air tanpa mengganggu kehidupan biota air di dalamnya. Tujuan penelitian untuk mengetahui perbedaan penurunan kadar BOD5 dan COD dengan pemberian berbagai dosis urine sapi fermentasi dan variasi waktu tinggal pada limbah cair PT. Sinar Sosro Ungaran. Urine sapi fermentasi digunakan untuk meningkatkan proses degradasi bahan organik oleh mikroorganisme di dalam air limbah. Metode penelitian yang digunakan eksperimental semu dengan rancangan percobaan pre and post test. Sampel penelitian adalah air limbah inlet dan outlet dengan tiga kali pengambilan sehingga jumlah sampel 54 buah. Hasil pemeriksaan rata-rata kadar BOD5 sebelum perlakuan adalah 1051 mg/l, sesudah perlakuan dengan pemberian dosis 10 liter dan waktu tinggal 5, 10, 15, 20 hari adalah 376 mg/l, 500 mg/l, 708 mg/l, 271 mg/l dan dengan pemberian dosis 5 liter adalah 723 mg/l, 61 mg/l, 568 mg/l, 179 mg/l. Hasil pemeriksaan kadar COD sebelum perlakuan adalah 2867 mg/l, sesudah perlakuan dengan pemberian dosis 10 liter dan waktu tinggal 5, 10, 15, 20 hari adalah 1027 mg/l, 1494 mg/l, 2121 mg/l, 820 mg/l dan dengan pemberian dosis 5 liter adalah 1973 mg/l, 181 mg/l, 1705 mg/l, 538 mg/l. Uji statistik digunakan Uji Anova Dua Arah. Hasil uji menunjukkan ada perbedaan penurunan kadar BOD5 dan COD dengan pemberian berbagai dosis urine sapi fermentasi dan variasi waktu tinggal. Hasil penelitian didapatkan bahwa kadar BOD5 dan COD air limbah perlakuan belum sesuai dengan Peraturan daerah Jawa Tengah No. 10 Tahun 2004 tentang Baku Mutu Limbah Cair Bagi kegiatan Industri Minuman Ringan sebesar 50 mg/l untuk BOD5 edan 100 mg/l untuk COD. penelitian sebaiknya dilengkapi dengan pemeriksaan kadar oksigen terlarut dan nitrogen di dalam bak aerasi. Kata Kunci: Urine Sapi Fermentasi, Lumpur aktif, BOD5, COD The Difference Of Degradation Between BOD5 and COD Contains By Giving Various Dosage of Cow's Urine fermentation and Various Retention Time In Waste Water of PT. Sinar Sosro Ungaran PT. Sinar Sosro Ungaran is a food and beverage company in bottle tea with the capacity of production is 200.000 liter per day. Waste Water Treatment is the unit of waste water processing to process waste water of production and from activities of manufacturing so that it can be threw away to rthe body of water without disturbing the life of biota in it. The purpose of this research is to know the difference of degradation between BOD5 and COD contains by giving various dosage of cow's urine fermentation and various retention time on liquid waste on PT. Sinar Sosro Ungaran. Cow's urine fermentation is used to increase degradation of organic substances by microorganisms in waste water. The research method is quasi experimental with the research design of pre and post test. the sample of this research are waste water of inlet and outlet with three times taken so that total of sample are 54. The result of average in BOD5 contain before treatment is 1051 mg/l, after treatment by giving dosage of 10 liter and retention time 5, 10, 15, 20 days are 376 mg/l, 500 mg/l, 708 mg/l, 271 mg/l also by giving dosage of 5 liter are 723 mg/l, 61 mg/l, 568 mg/l, 179 mg/l. The result of COD contain before treatmnet is 2867 mg/l, after treatment by giving dosage of 10 liter and retention time of 5, 10, 15, 20 days are 1027 mg/l, 1494 mg/l, 2121 mg/l, 820 mg/l also by giving dosage of 5 liter are 1973 mg/l, 181 mg/l, 1705 mg/l, 538 mg/l. The statistic test used id Two-Tailed Anova. There was significant difference of degradation between BOD5 and COD contains by giving various dosage of cow's urine fermentation and retention time. The research concluded that the BOD5 and COD contains in treated waste water are not adaptable according to Peraturabn Daerah Jawa Tengah No. 10 tahun 2004 about Standard Quality of Liquid Waste For Sosft Drink Industry Manufacturing namely 50 mg/l for BOD5 and 100 mg/l for COD. The next research could be better if completed with control the dissolved oxygen contain and nitrogen contain in chamber aeration. Keyword : Cow's Urine Fermentation, activated sludge, BOD5, CO

Comparison of Academic Progress and Social Development for Retained and Socially Promoted Spanish Speaking Children in an International English-Medium School

This two-year study was designed to investigate the effects of grade retention on a child\u27s academic progress, English proficiency, and social development. All students (n=17) were native Spanish-speaking children, living in a Spanish speaking country, learning in an English-medium school. Each retained child was matched with a child in a control group and a child in a socially promoted group, based on age, sex, Sanford Achievement Test scores, and final reading, language, and math scores. The Piers-Harris Children\u27s Self-Concept Scale (PHSCS) and the Comprehensive Receptive and Expressive Vocabulary Test (CREVT) were administered in the fall and spring for two consecutive years. Final reading, language, and mathematics scores were collected at the end of each year, and teaching rating scale surveys were collected at the conclusion of each semester. Because of the relatively small sample size, the results were analyzed through the use of bar graphs and the description of basic trends in changes among all three groups of students. The results indicated retention is an ineffectual means for increasing English proficiency and academic progress. Alternative educational practices must be considered