Retted (White) Coir Fibre Nettings-the Ideal Choice As Geotextiles For Soil Erosion Control

摘要

India produces the best quality of coir fibre (Cocos nucifera) by retting the matured green coconut husks in waters for 6 to 10 months. It is mostly used for manufacture of mats, mattings and carpets. This fibre is free from the toxic phenolic materials which are usually present on the surface of brown fibre, extracted mechanically from dry husk. The retted fibre is also comparatively less sensitive to UV light due to leaching out of photo-sensitive materials from its surface during retting process. Yarn made out of retted fibre has superior strength compared to the yarn made out of brown fibre. Recently a unique process has been developed by Central Coir Research Institute of Coir Board by which green husk fibre can be retted by Coirret (a bacterial cocktail) within 72 hrs. A wide variety of geotextiles ranging in densities from 400 to 1400 grams/m~2 of coir nettings can be made for different applications. Experiments were conducted in 1995 at three different sites using coir nettings as erosion control material. A canal bank and road slopes at two different sites were chosen for this purpose.