Judul: Optimalisasi usahatani tanaman semusim tingkat petani : Di Proyek Rehabilitasi Lahan Kritis dan Pengedalian Sumberdaya Alam Danau Singkarak, Propinsi Sumatera Barat
Abstrak: Di dalam penanganan lahan kritis, semi kritis, dan potensial kritis pada kawasan lahan pertanian perlu dila- kukan penerapan teknik-teknik rehabilitasi lahan kritis dan konservasi tanah tingkat petani dengan menggunakan pola sistem usahatani konservasi. Di dalam sistem usa- hatani konservasi tidak hanya bertujuan menghijaukan lahan tetapi juga memberikan peningkatan pendapatan serta menyerap tenaga kerja di sekitar wilayah lahan kritis. Untuk mendukung Usahatani Konservasi, keikutsertaan petani dalam proyek baik dalam perencanaan dan pelaksanaan serta evaluasi perlu dikembangkan untuk pemanfaatan sumberdaya yang dimiliki petani secara optimal. Oleh sebab itu permasalahan yang terdapat dalam upaya usahatani konservasi dan peningkatan pendapatan petani dilokasi lahan kritis dapat dirumuskan yaitu apakah petani telah melakukan pemanfaatan sumberdaya yang dimiliki secara optimal dalam upaya peningkatan pendapatan usahataninya.
Keyword: 

Judul: Analisis investasi sistem usahatani konservasi dikawasan proyyek rehabilitasi lahan kritis dan perlindungan sumberdaya alam Danau Singkarak, Sumatera Barat
Abstrak: Jumlah penduduk yang semakin besar disertai pertumbuhan yang relatif tinggi membutuhkan pangan dan jasa sumberdaya alam lainnya yang semakin besar. Sumberdaya lahan kering peka terhadap bahaya erosi maka tekanan yang semakin besar terhadap lahan kering mengakibatkan permasalahan konservasi menjadi penting. Kerusakan tanah pada dasarnya akibat manusia telah melakukan eksploitasi tanah sampai melampaui batas kemampuan tanah tersebut. Dilihat dari pandangan ekonomi, eksploitasi tanah sebagai salah satu sumberdaya dalam produksi pertanian adalah untuk memperoleh pendapatan bersih dengan biaya yang serendah-rendahnya. Penelitian ini dilakukan pada empat desa di kawasan Danau Singkarak yaitu Desa Murapi Selatan, Duo Koto Malalo, Sumpur dan Pabalutan. Dipelajari keadaan usahatani lahan kering dihubungkan dengan aspek konservasi, perbedaan tingkat pendapatan petani yang melakukan konservasi dengan yang tidak dan tambahan biaya dan manfaat dari kegiatan usahatani konservasi. Analisis investasi dilakukan dengan melihat kelayakan kriteria investasi Net Present Value (NPV) Net B/C dan Internal Rate of Return (IRR).
Keyword: 

Judul: Biology and ecology of the buffalo fly, haematobia exigua de meijere (diptera:muscidae)
Abstrak: The life history of the buffalo fly was observed at room temperature of 27°-29.5°C and at a relative humidity of 48-68 percent. The eggs hatched after 17-22 hours, with an average of 18 hours. First instar larvae measured 1.25 + 0.16 mm long and 0.27 + 0.037 mm wide. reach the second larval stage. It took 6-12 hours to the second instar larvae measured 2.676 +0.187 mm long and 0.353 +0.028 mm wide. The second instar took about 12-24 hours to reach the third larval stage. The third instar measured 6.833 + 0.189 mm long and 0.919 + 0.051 mm wide. It took about 2-3 days for the third instar to become pupae. Duration of the pupal stage was about 5-7 days before the adults emerged. Under laboratory condition, the buffalo fly completed its life cycle in 9.5 to 10.5 days, whereas under field condition it took 9-14 days with an average of 10.5 days. The growth ratio which was based on the measurements of the cephalo-pharyngeal skeleton of each instar was 1.797. The preoviposition period was 8-12 days and mating usually occurred on the 6th or 7th day. The longevity of the male was 29 days, whereas it was 32 days in the female. The range of egg production under laboratory condition was between 20-139 per female fly. The belly and hind legs of the carabao were the most preferred habitat either during cloudy and cool dry or shiny and warm day. When the weather was clear and the carabao was in the shade, the flies tended to be more distributed particularly on the shoulder, dewlap, back and horns. The carabaos had relatively fewer Musca sp. and Stomoxys calcitrans than cattle; never the less carabaos had a higher infestation of buffalo fly than cattle. Oviposition occured either during the day or night but the buffalo flies were more active during the night than in the day time. The effect of various lengths of exposure time of manure in relation to the oviposition was profound. observed, the maximum number of the buffalo flies was occurred when the dung was exposed for 30 minutes. With increasing time of exposure the number and variety of insects also increase. It was evident that Sepsidae and psychodidae were the most dominant insects emerging from the dung. The number of buffalo flies also increased with increasing
Keyword: