Hydroseeding and hydromulching - emerging options for reclamation of mined out areas

摘要

The reclamation and revegetation of mined out areas and spoil dumps offers a great challenge as more often they do not have a suitable surface to provide bedding layer for anchorage and support, while in other cases they do not support plant survival and growth due to presence of toxic material. Gradual increase in such landscape due to intensive mining activity may endanger not only the agriculture productivity but also the ecosystem and the ecological balance. This warrants the need for immediate steps for land reclamation with appropriate scientific background to achieve complete reclamation as the existing mining law requires the establishment of a healthy, permanent vegetative cover on all land affected by mining, once mining is completed. Such landscape disturbances not only aggravate the problems of land degradation and water pollution but also affect the agro productivity in the country unless appropriate measures are taken to reclaim the land and. restore the land productivity and fertility. In view to eliminate the negative impact of mining on land ecosystem, socio-economic status, and eco-development, the reclamation of mined out areas and. mine spoil dumps and restoration of land productivity must be considered as an integral part of mining activity as is considered in the developed countries. The vegetative planting technology (VPT) which is based on hydroseeding and hydromulching is the recent development being practiced internationally in reclamation of mined out areas particularly where the area is inaccessible and difficult to reclaim. Hydroseeding is the hydraulic application of a seed and fiber mulch to a soil surface. This technology will not only helpful in stabilization of the dumps but also will create an aesthetic landscape of the mined out areas. It will promote quick restoration and redevelopment of mined out area into the landscape. Hydromulching is an improved method of hydroseeding in which mulch is added to the mixture. Although there are conventional methods available to mitigate the impacts due to mining which can be attained by plantation, but it lacks in diversity and resemblance to the undisturbed native community in the surrounding landscape. It is possible that with the help of VPT the inclusion of plant species that attract a diverse bird population would increase the potential of seed dispersion from the surrounding area. Soil amendment ingredients such as mulch or compost, combined with soil stimulants and the correct seed specie mixtures, including a combination of grasses, forbs and shrubs to help diversify the plant root depths, are ingredients for success of VPT. This paper highlights the salient features, the processes and other aspects of hydroseeding techniques with one of the case study in GREECE and has suggested how it may be applied in the reclamation process of mined out areas.